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[Question] [ I’m in the process of making my own original series where I have all types of biologically feasible cryptids and monsters in it. In this series, I’m planning on having vampires being a species that broke off of humans at some point in our evolution. I was thinking homo erectus but more on that in a future question. But basically I’m having them be a more carnivorous species than us, that evolved to be nocturnal. And some of the adaptations I came up with are cooler body temperatures, pale skin, and most interestingly, black sclera. Does anybody have any idea if it’s even possible for sclera to be black? I was thinking it’d be caused by a mutation that helped hide the whites of their eyes (seeing as how we evolved to show so much of our own sclera so others could tell where we were looking so with this, it’d be harder for their prey to tell where they’re looking). Or do you think it’d be more possible to make them voluntarily turn their sclera black when they’re hunting, similar to how chameleons and cephalopods can? [Answer] Possible? Most likely, since other primates, like gorillas, have this trait, although they also have cases of white sclera[![enter image description here](https://i.stack.imgur.com/7zXjT.jpg)](https://i.stack.imgur.com/7zXjT.jpg) Simply having a pigmented sclera sounds a lot easier of a trait to have than having eyes changing color, since that would require special chromatophores covering the entire sclereal region and acting like those found in an octopus' skin. In addition, there's yet another solution for your nocturnal vampires: large pupils. [![enter image description here](https://i.stack.imgur.com/KT3ny.jpg)](https://i.stack.imgur.com/KT3ny.jpg) This is a leopard seal, a powerful predator. To make most of the light available in their dark aquatic environment, they have large eyes and pupils capable of dilating to a very large size, thus creating a bigger entrance for the already scarce light. Despite these black eyes, their sclera seems to usually be either white or reddish white. This trait is also shared by many nocturnal predators and could be a great alternative considering your vampires also hunt in low light conditions and would allow them to look more human (pupil contracts revealing a more or less normal looking eyes, maybe with a slightly larger pupil, allowing them to pass more easily as humans should the need arise). [Answer] *OF COURSE, BUT...:* As all the other answers to this question have pointed out, it is certainly possible to have black sclera, and it can certainly evolve. It is not uncommon for animals to have [a sclera matching their eye color](https://en.wikipedia.org/wiki/Sclera). The question is, do you want it to? For your nocturnal variant on Homo sapiens, there are some hunting advantages to dull eyes, but if your primary prey is humans (like vampires are traditionally portrayed) then it may be a bad idea. Giving a reason something evolved is always a bit of conjecture, but the theory is that [the sclera enhances communication among people](https://en.wikipedia.org/wiki/Cooperative_eye_hypothesis). If you want to communicate with people, or if vampires are communal hunters like humans, then this could interfere with hunting. If humans aren't their primary prey, then being able to coordinate with humans is a valuable skill, and anything interfering with that is bad. Have you ever googled black sclera and seen the pictures of the people using contacts? Even if they aren't deliberately trying to look evil, they do. I've used this in stories as a trait to make a character more alien than their fully human counterparts. If you are seducing your prey, you don't want to scare them away. Looking scary isn't usually helpful unless terror is the hunting style (like maybe for werewolves). If the goal is to work alongside humans, the same rule applies. Although I can't say exactly how the musculature would work, I can imagine a vampire whose eyes have adjustably SIZED pupils, and that contract to have a small (human-sized) appearance in the presence of light. There would be something slightly off about how their eyes adjusted to changing light conditions, but it wouldn't be grossly obvious. In the dark, the pupils would expand to fill the area occupied by sclera, covering the whites, and this would take the place of dilating pupils. Your vampires would still have a "tell" to observant humans, but it wouldn't be quite so — evil — in appearance. [Answer] Chimpanzee sclera are very dark. [![chimp eye](https://i.stack.imgur.com/zsKQ4.gif)](https://i.stack.imgur.com/zsKQ4.gif) [Scleral pigmentation leads to conspicuous, not cryptic, eye morphology in chimpanzees](https://www.pnas.org/content/116/39/19248) Chimps are our closest relatives. They have sclera considerably darker that their irises, as depicted. It is not clear why they have light irises set off against dark sclera and we are vice versa. But if they can do it, then it is reasoble for another closely related hominid like your vampires to do it. ]
[Question] [ An unpowered alien pod drifts into our solar system. No particularly advanced technology is present on it. But the pod is full of ejected hazardous waste (say, between 10-1000 tons) from an alien civilization and dumped into interstellar space thousands or millions of years prior. Earth technology is several centuries advanced from the current time and there is no particular global crisis. When the nature of the hazardous waste is identified, conflict and war break out among those struggling to obtain the waste. * It should be something an advanced civilization would have discarded like an industrial byproduct, and considered useless by the originating culture - hazardous enough they launched it into space rather than incinerating/recycling it. * The waste must not be information or technology (like scriptures, nanites or broken warp coils), although it can be a product of technology that we can't produce (some sort of weird fullerene variant? Why would that be hazardous or useful?) I prefer not to have living waste (like psychic aliens making people value them) * It must be so unambiguously valuable that humans are willing to break treaties and betray allies in order to possess it. * I would prefer that it be a material, like unstable dark matter (just to make something up) or the whole thing consists of antimatter iron in a magnetic cradle. * I would like it to be something that doesn't violate physics (no Pixie dust), ideally something that has been theorized to exist but not made/proven yet (like if there's a stable isotope of californium, if that's even possible, and why that would be useful). * It should still be hazardous, so the risk in obtaining it is great, even without the conflict. What is it that they've found aboard that pod? Explain why it is hazardous and why it is valuable, if that isn't readily clear. [Answer] Please see my answers to: [What would be the most expensive material to an intergalactic society?](https://worldbuilding.stackexchange.com/q/141006/21222) And: [Could there exist a quantum virus which breaks someone's body down to fundamental particles?](https://worldbuilding.stackexchange.com/q/52074/21222) In my answers I mention strangelets, a form of matter that works like [katamaris](https://en.wikipedia.org/wiki/Katamari_Damacy#Gameplay). The TL;DR explanation of strangelets is this: > > (...) a strangelet coming into contact with a lump of ordinary matter could convert the ordinary matter to strange matter. This "ice-nine"-like disaster scenario is as follows: one strangelet hits a nucleus, catalyzing its immediate conversion to strange matter. This liberates energy, producing a larger, more stable strangelet, which in turn hits another nucleus, catalyzing its conversion to strange matter. In the end, all the nuclei of all the atoms of Earth are converted, and Earth is reduced to a hot, large lump of strange matter. > > > Source: [this Wikipedia article](https://en.wikipedia.org/wiki/Strangelet#Dangers). The text in it has since changed, but the content is much still the same. I think this is the best match for your requirement that it must be: > > hazardous enough they launched it into space rather than incinerating/recycling it. > > > And: > > (...) something that doesn't violate physics (no Pixie dust), ideally something that has been theorized to exist but not made/proven yet. > > > Also check this awesome Kurzgesagt video on how strangelets work: [The Most Dangerous Stuff in the Universe - Strange Stars Explained](https://www.youtube.com/watch?v=p_8yK2kmxoo). [Answer] Metamaterials The waste genuinely is just garbage. The catch is that the civilisation that produced it does seriously cool things with material-science, and while most of their waste can be recycled, a small amount cannot. Meta-Materials can have incredible properties, we manufacture them in various forms now in the 21st century so imagine the possibilities of a civilisation many centuries more advanced than us. Matter-sieves Light-bending fabric (invisibility cloaks) laser-focusing blocks Self-healing materials The list goes on and on. A lot of the applications are quite mundane industrial uses. A light-bending foil/fabric would be excellent for optics and telescopes, matter-sieves can filter liquids and gases without significant energy input, self-healing plastics can repair damage done to them. Being able to unravel how they work and how to manufacture them would potentially revolutionise a lot of industries. The catch is that their complex structures are hard to break down and recycle, so when no longer needed, they're just trash. Some metamaterials are quite dangerous to handle. for example a particularly effective matter-sieve might do unpleasant things to your hands if you touch it... A Self-healing polymer might grow over anything it touches, trapping unfortunate astronauts inside it like a mosquito in amber. One metamaterial being developed now mimics the behaviour of gecko feet. the idea is to allow people to climb vertical surfaces like a gecko. nearly microscopic hairs in the gecko's foot penetrate the material and provide enormous surface area to grip with compared to the overall size of the foot. with the quirk that it peels off like a sticker. Now imagine gecko-foot material sheets in a trash-tangle...impossible to detach from anything that touches them. Any effort to escape just tangles the victim further and slowly draws them irretrievably into the mess... Attempting to retrieve the materials from the space pod is highly dangerous because innocuous objects can have dramatically unexpected properties, some of which might prove lethal. [Answer] Anti-matter blobs. Raw blobs. No "magnetic cradle" needed - that would not survive millions years in void anyway. Why thrown away? Imagine those advanced aliens have some (Pixie dust, yes. But Pixie dust somewhere away outside of the "novel" plot) ultra-powerful energy generation process, that creates anti-matter in huge quantity as a waste. The quantity though has to be real huge, that annihilating it at place would not be just bonus energy, but more of destruction of alien's homeworld. Or, maybe, it was not the energy they were creating, but rather they were creating the matter itself out of vacuum. World-building taken literarily. Not terraforming of pre-existing planets, but rather using energy to tear vacuum into matter and anti-matter, then using this matter to create new planets for their living (maybe even drifting planets, like in Niven's Ringworld) and safely throwing anti-matter to void infinities. Why craved by humans? Well, exactly because it is an ultimate weapon! Capture it, manage to split and control (EM fields?) - and you can throw onto your enemy millions of bombs much more powerful (and much more environment-friendly!) than those vintage old school nukes. And if not used - mere blob has much more longeviety than hyper-complex tech of plutonium warhead. Just shield it from Solar wind and it can be stored for ages, as long as you can generate EM field anchoring those blobs in space. Back to our XX century - our militaries tend to throw away spent tin cans, from meals or from cartidge boxes. And what use can a stone-age tribe make of metal, even if we ourself consider tin too soft to make blades of, but they have no any metal at all! Or, if you do not want to go for grim comedy, then anti-matter might be craved mostly as ultra-rich power source, rather than weapon. Afterall all power sources have "dual use" (military and civilian depending how you arrange energy extraction). And instead of "kill them with fire" Earth nations would plan to destroy each other economically, leveraging ultra-cheap abundant energy. Bonus point, if this "free energy" is not a "benevolent gift" or a random by-product, but a nefarious plot to destroy Solar system itself by our own hands. Which can be slowly revealed by charting those blobs and finding them not scattered all directions randomly, but precisely aimed at us, with regard to galaxy rotation. But here we tread into Asimov's "Gods themselves" :-) UPD. @cowlinator brings a point of antimatter slowly "melting away" due to residual cosmic dust, star winds, maybe dark matter. I can not guesstimate matter density in interstellar voids. Nor the expected distance/ages of travelling in a novel. However this hints at one more plot device: approaching Sun the blob would be subject to quadratically increasing Solar wind flow, which would cause quickly increasing annihilation - light radiating, which would allow Earth to detect this object incoming, and maybe to try looking for halo of similar blobs drifting outside of Solar system too. [Answer] The one who controls the spice, controls the galaxy You could make it add a temporary psychic link to whoever consumes it due to the whole waste cloud being quantum entangled in a unknown way. It could just be like Oxigen. A powerful chemical that can power creatures and machines, but is a waste product of other organisms (plants for the oxigen RL example). Check the periodic table for the theoretical highest undiscovered element. It could improve the society just by being a powerful energy source that breaks down in other useful elements during the power extraction. Having a better way of life is always a good way to start fighting between peoples, as no one wants to be left out. It could possibly be used to enhance people, making them smarter, stronger and longer young. Think of people learning languages like when they were a baby, or growing muscles to the max fitness while just resting. Or giving people the power to make their conscious mind tap into the vast power of the unconscious, able to hold so much information that science jumps ahead by leaps and bounds. Edit: Or just a drug. The drug filtering into the atmosphere is already enough for everyone to start craving the real stuff. [Answer] Aliens themselves. The pod is not a garbage can, but rather a burrial tomb, sent in space either: * as part of burrial ritual (in that case, the alien inside might be an important individual), * or perhaps because the bodies inside are victims of unknown plague that broke out on a space ship (it was easier to dump them in space, than to incinerate them) Why would humans fight over it? Could examination of the bodies bring any breaktrough in medicine or other fields? "Earth technology is several centuries advanced from the current time": Do humans believe they can analyze their brains and recover possible leftover memories? Could they even attempt to bring them back to life, at least partially or temporarilly? Not sure if the answer suits your question, but in the second scenario it is hazardous alien waste, possibly hazardous even to humans, and it's not a living waste. [Answer] extra-dimensional matter Extra-dimensional matter can be used like anti-matter and be annihilated to produce energy. However, since atoms are on the order of 10^-10 meters a 10X10X10X10 cm cube (10 cm on each side) has a billion times more power than even normal anti-matter. Why is it waste? The beings that made it exist in 5 space so this 4 dimensional matter is considered an impurity and would have trouble moving things in 5 space at all. So it is harvested and ejected to ensure efficient and non-turbulent fuel flow. They throw it out and eventually the unpowered cargo ship stabilizes to the most stable 5 d coordinates, (x,y,z,0,0) that is to say, three space with no variation in the 4th or 5th dimension, or our universe. The 5 dimensional beings don't care because they exist on a higher or lower position in the two other dimensions since there is more higher dimensional matter there. So when 1000 tones of extra dimensional matter comes into orbit everyone realizes that there is currently more energy in that material than all the matter in all the fissile material on earth and that ownership of the craft means energy independence forever and unlimited military applications. [Answer] The totality of its properties are not known. [![aliens](https://i.stack.imgur.com/kyP1A.png)](https://i.stack.imgur.com/kyP1A.png) <https://mondobizarrocinema.blogspot.com/2013/08/meeting-my-criterion-repo-man.html> In the movie Repo Man, there may be dead aliens in the trunk of a Chevy Impala. There is definitely something in the trunk. What, you have never watched Repo Man? Callow youth! Watch it! And do not click on links to learn more about the movie or go to you tube to see clips. Just watch it from the start. In any case the nature of these aliens or whatever is in the trunk is not made clear. They can definitely do stuff, and do, in one of the weirdest and most awesome endings of any movie. Many parties want that car though their motives are not made clear. So too in your story. The totality of what this alien material might be able to accomplish is not made clear. The conflict among people wanting the material is very clear. As to what could happen when someone finally does take possession of this material, I again refer you to the end of Repo Man. [Answer] Too long to fit into a comment, sorry. Nothing specific, just a very vague... feeling more than a concept. Thinking about some folklore (golden antilope, or a food-brewing pot unstoppable once activated in greed)... Or some fantasy books, including Warhammer 40k... Our seemingly huge universe is a bubble inside some not merely hostile, but unimaginably and inconcilably alien real infinity. In their scientific rush alien beings managed to burst a hole in the bubble skin and now this real-alien somethingness squeezes in. It is not bad or good, it is absolutely inconcilable with our existence. Like Ice-9 in space. They can not patch the hole or somehow push it back, they only managed somehow to split it to pieces and desperately throw it away, to keep their own star system from being immediately consumed. Consider it environmental disaster on a space opera scale. Problem is, i can not come up with any plausible reason Earth nations would want it, short of some grotesque dark cultists. [Answer] The pod could be organic. Organic ships (organisms tailored to be able to consume fuel, fly in space, ferry cargo or weapons and REPRODUCE, creating more ships out of raw material) should be the apex of any space civilization goal. Humans are unfamiliar with anything lose to it as of now, since our genetic researchers are yet to allow the creation of new species, rather than use science only to treat genetic ilnesses or in some cases improove already existing or endangered organisms. Whatever balance the power board have on the earth at your time would be chaotically shifted if one nation held the controll of this new piece. The pod, however could have been discarded for a reason... Maybe it's genetic code suffered a mutation, maybe the pod itself is an egg of such ship vessel... Maybe it is a cancer removed by the ships engeneers, who could have evolved to live within them like parasites live inside whales, completely depedent, and yet these aliens would have changed their biology to connect with the vessel by a cranial nerve, and without such, the ships would never accept being flew by humans or any other species. Or maybe the pod is infected by a bioweapon of the same civilization, engeneered to decompose metal alloys, kiling the aliens inside but leaving the ships almost intact. Lastly, if none o that works, maybe the pod came from other point in time. The last surviving record of a war fought between the current ruling nations, or a glimpse of a possible future, showing which of them shall rule upon the rest. ]
[Question] [ ## Background I just read this [question](https://worldbuilding.stackexchange.com/q/154420/67246) about how to get a planet to have one hemisphere with [tropical](https://sciencing.com/hot-equator-but-cold-poles-6908312.html) climate and one with polar climate. The (not yet accepted) [answer](https://worldbuilding.stackexchange.com/a/154421/67246) with the highest score recommends placing large enough mountains on one hemisphere, so that simply by altitude, it would be cold on the ground. ## Question Now I ask myself, what would have to happen to a planet so that exactly one hemisphere is (exclusively) full of high mountains whereas the other hemisphere is entirely flat? ## Related [This](https://worldbuilding.stackexchange.com/q/30110/67246) question might be the same as mine, just inverted. I do not know if this is the case though, and I also do not find the higher-scored answers to be answering my question. ## Edit Since it came up in the comments: I'm only asking about landmass. The underwater topology does not factor in here, since the question linked above is framed in terms of human habitat. [Answer] It turns out there's something very much like this, right next door to Earth. Observe the topography of Mars: [![enter image description here](https://i.stack.imgur.com/QW7ID.jpg)](https://i.stack.imgur.com/QW7ID.jpg) (Image courtesy [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/thumb/1/1d/Mars_Map.JPG/800px-Mars_Map.JPG); larger version [here](https://upload.wikimedia.org/wikipedia/commons/2/2c/Mars_topography_%28MOLA_dataset%29_with_poles_HiRes.jpg).) The large blue areas in the northern hemisphere, making up about a third of the surface, are about 4 to 6 km lower in altitude than the yellow/orange highlands to the south. This dramatic discrepancy is known as the [Martian dichotomy](https://en.wikipedia.org/wiki/Martian_dichotomy) and there are two major schools of thought for how it came about. The first is that the dichotomy represents one or more colossal impact craters. If it was from a single impactor, it would be the largest impact crater in the solar system. Opinions are divided as to whether a single impact can explain the resulting geography, or whether it's better modeled as multiple (still massive) impacts. Of course you could do either. The other theory is related to long-ago Martian tectonics. The theory goes that for reasons unknown (and this is still an active subject of research on Earth, let alone Mars), one hemisphere featured one or more huge upwellings of material from the mantle into the crust, and the other featured downwellings. Over an extremely long period of time, the result is that crustal material migrates from one hemisphere to the other. (The average thickness of the southern crust is twice that of the north.) In the case of Mars, the dichotomous hemispheres are north and south, but this may just be coincidence. Neither process has any particular reason to favor one orientation over another as far as I know, so having a dichotomy between east and west hemispheres should be possible. Note that there are still local variations: there are craters and mountains in the north part of Mars, valleys in the south part. However, the difference should be enough to establish the broad climate dichotomy that you're looking for. [Answer] Here is a more speculative explanation. 1. The planet is tidally locked to its star. <https://en.wikipedia.org/wiki/Tidal_locking> The result: one side is always bright and the other dark. The bright side is a lot warmer than the dark side. 2. The planet's surface is made largely of volatiles. Water would work. Other ices like methane or ammonia would work. 3. On the hot side, the surface material sublimates or evaporates in the perpetual day. When the gaseous material gets to the dark side, it precipitates out as rain or snow. Once it is over on the dark side it is never going to melt again. It piles up. This results in the gradual transfer of crust from the hot side to the cold side. The hot side would flatten out as it was stripped away. The mountains on the cold side would not be rocks, but more like glaciers. [Answer] Quickest solution - one hemisphere is where all the tectonic plates meet. Or if there are some on the other one it's under the ocean so the height of the "mountains" don't have influence on the weather above. Other solution could be - mountains from rocks soft enough to be levelled with glacier and erosion. Fun and make for good storytelling solution - there was a time when the moon of the planet didn't covered planet during meteorite shower that destroyed the mountains (assumption must be needed that the both hemispheres are just mountains and valleys so there is no planes where meteorite could create mountain range by making a very big hole) [Answer] The moon's center of mass is about 2km from it's geometric center. If you covered it with water, sea level would be more-or-less centered on the center of mass, so the ocean would be much deeper on one side than the other. And if you covered it with an atmosphere, the atmosphere would be much thicker -- i.e., denser at the surface -- on one side than the other. As I understand it, this discrepancy in centers is thought to be related to the moon's mode-locking to the earth. So, to have a planet with a normal day-night cycle that forms this way, you would have to re-spin it, possibly about a different axis than the orbit. What's harder, you'd have to re-spin it without breaking up or melting the crust. And you might have to remove the body it was mode-locked to. One problem with your question shows up if you want an earth-like percentage of ocean. The low terrain would mostly flood and be ocean floor. If you want lots of ocean, and land masses in both hemispheres, and a high / low distinction between the hemispheres, you need a more complicated situation. ]
[Question] [ I saw this question here: [Can I have wind turbines on my base?](https://worldbuilding.stackexchange.com/questions/123374/can-i-have-wind-turbines-on-my-base) and someone else asked about how the planet can have 60-100mph winds without very much sunlight to cause the energy differential, to which OP never gave a response. I'm now curious if there's any ways for this to occur naturally to a planet with little to no sunlight. Background (Copied from OP) A colony of humans has settled on a remote planet where there is little to no sunlight, but there is a plentiful amount of earth metals. E.g.- Iron, aluminium, Titanium, etc. There are high speed consistent winds that make it ideal for harvesting electricity from wind (speeds of 60 - 100mph.) Question How can this planet have high winds with little to no sunlight? What else could be causing high winds on a metal-rich planet like the one described? [Answer] To generate winds you need a temperature differential within the planet. Normally this is provided by the sun, heating at different temperatures different places. However, you can have differential heating for several other reasons: * geological activity: a lake of molten material erupted from below the surface will be hotter than the surroundings, generating a strong wind * astronomical impact: the impact crater will be also really hot immediately after the impact, with again the result of generating winds * tidal heating: local increase of temperature due to strong tidal deformation can transfer heat to the atmosphere, again generating wind [Answer] It's not entirely true that you need a lot of sunlight to generate high speed winds; and example of this is [Neptune](https://www.space.com/21157-uranus-neptune-winds-revealed.html). If you're willing to wait around for a while (geologically speaking of course) then even on a low energy planet, windspeeds will pick up. Why? Because it not only takes energy to start the wind, but it also takes energy to stop it. All it takes is a minor differential in temperature over a long time to start the wind but there won't likely be a lot of energy left in the system to stop it. Ultimately, this is less likely to happen on a planet that humans find comfortable (because our comfort involves a lot of energy) but it certainly can happen if you have a terrestrial planet in an orbit further out. Whether that is likely given our current understanding and models of planet formation I'll leave for another question. [Answer] # Planet spin can't drive wind speeds for a rocky planet Let's assume the planet in question is rocky and generally Earth-sized. In this case, the rotation speed of the planet will not be directly related to its wind speeds. First, the Coriolis effect is not a force that can drive an object to move. Instead is it a deflection of a moving object. [Acceleration due to the Coriolis effect](https://en.wikipedia.org/wiki/Coriolis_force#Formula) is given by $$\mathbf{a}\_C = \mathbf{v} \times \mathbf{\Omega}.$$ The bold symbols mean we are talking about vectors. If the velocity vector is zero, then acceleration is zero. Second, we can see from our solar system, that rotation speed doesn't control wind speeds. The [rotation Venus's surface](https://en.wikipedia.org/wiki/Venus#Orbit_and_rotation) is about 7 km/h while the Earth's is 1700 km/h. Meanwhile, [Venus has constant wind speeds](https://en.wikipedia.org/wiki/Venus#Atmosphere_and_climate) around 300 km/h at the cloud tops, circling the planet every 5 hours or so. Earth's winds are obviously not that strong. But let's use the Coriolis effect to help with driving fast winds... # Start with a strong magnetic field While the planet's spin can't really drive winds the way we want it to, the spin of the core can do some neat things. Specifically, we could get it to make a ferocious magnetic field, and then use that field to do some stuff. A powerful magnetic field can induce charge particles to move. Ocean water is full of such particles, specifically the ions of dissociated salts (and water's hydrogen bonds make even electrically neutral water molecules act like they are charged in some circumstances). [![enter image description here](https://i.stack.imgur.com/VTyBN.gif)](https://i.stack.imgur.com/VTyBN.gif) Magnetic field lines on Earth look like the diagram above. The magnetic field lines point from north to south. For this planet to work, we imagine that water is circulating along the green line (magnetic equator), from east to west (right to left on the screen). Along the green line, the direction of the flow is perpendicular to the direction of the magnetic field lines. Lorentz force magnetic acceleration of a charged particle is $$\mathbf{J}\times\mathbf{B}$$. $J$ is current flow in our ocean. We need this to be in a direction such that a strong magnetic field will force acceleration in the east to west direction as indicated. This is the basis of [magnetohydrodynamic propulsion systems](https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive). Current systems are limited by the conductivity of seawater. On our planet, we'd want to add lots of salts to the seawater to make this work. One way to do this is to make the planet mostly land area; with a smaller ocean, runoff from the land will be more significant and the ocean will be much saltier. We get the ocean accelerated to high speeds around the magnetic equator, and it then 'drags' the atmosphere along with it. This is the same principle in reverse of how it works on Earth. Now we have a constant, high speed west to east wind flowing on Earth. # Now add the effect of the normal [Hadley Cell](https://en.wikipedia.org/wiki/Hadley_cell) The Hadley cell is caused by differential heating between the equator and subtropical areas within about 30 degrees of the equator. It depends on warm moist air converging near the equator. So lets make sure the equator is very warm and moist; lets make it an ocean! This works will with both ensuring that we have ocean flow along the entire magnetic equator, and also allows us to have a 'small' salty ocean by leaving only this part of the planet covered in water. In the Hadley flow, heat and moisture is transported equator-ward on the surface. Thus, let's make the edge of the continents as dark and wet as possible, by covering them with rainforest. Lets also make the Hadley cell more stable by leaving it in the same place all year. Due to Earth's 23 degree inclination, the center of the Hadley cell, called the Intertropical Convergence Zone, moves from the Tropic of Cancer to the Tropic of Capricorn all year. Instead, let's have it stay stationary over the equator by giving the planet near-zero orbital inclination. With the Hadley cell as strong as possible, it will be generating equator-ward air flow, towards the already rapidly moving equatorial ocean. Now we need to bend that air flow in a westerly direction to get it to add to our wind speeds. Enter the Coriolis effect! Trade winds on Earth are bend westerly in the tropics, so now we need to spin the planet as fast as we can to direct as much of that energy as possible in the westerly direction, as seen on the graphic below: [![enter image description here](https://i.stack.imgur.com/aN4K2.png)](https://i.stack.imgur.com/aN4K2.png) # Conclusion We have a planet with: * A very strong magnetic field, lined up closely with the magnetic north and south poles. * Two continents covering most of the northern and southern hemisphere * A very salty ocean restricted to a band within ~10 degrees of the planetary and magnetic equator. * Magnetically induced, high velocity, west to east ocean current. * A low inclination leaving the sun and ITCZ over the equatorial ocean all year long. * A fast rotation and short day, so the Coriolis effect helps most of the power of the Hadley cell reinforce the equatorial winds. * Thick jungle from ~10 to ~30 degrees north and south, absorbing as much solar radiation as possible. In the end you get constant, extremely powerful trade winds in the desert regions mentioned above. In particular, 'off-shore' wind farms in the equatorial ocean would be able to harvest a lot of energy. Enjoy your hurricane-force planet! [Answer] Do you need high windspeeds everywhere, or just in localized areas where power generation will be situated? If the latter, you just need convenient geology to concentrate otherwise low-power winds. E.g., a canyon that concentrates wind through a mountain range next to a seacoast with a consistent current that keeps the air temperature over the water (or whatever liquid your oceans are made of) just slightly warmer / colder than the neighboring land. If you want consistent global windstorms, such as occur on Mars... well, the mechanism that creates them on Mars clearly works! Just so long as you have some small amount of sunlight, you can make use the seasonal variations in that sunlight to periodically condense and evaporate large portions of the atmosphere. On Mars, this means freezing out CO2 as dry ice on the south pole during southern winter, resulting in prevailing winds towards the south, and evaporating it again during southern summer, resulting in prevailing winds towards the north. A similar process operates on Pluto with nitrogen ice, so you really don't need a ton of sunlight to drive it. [Answer] To figure out how wind speeds work on a planet far from the sun, we can use two real-life examples- Neptune and Uranus. [This answer](https://astronomy.stackexchange.com/a/124) has some of what was mentioned in other answers, but it also gives a good source that explains why those winds are so strong. Neptune clearly doesn't have enough sunlight to cause wins. One possible answer suggests that these huge windstorms exist because of the lack of sunlight reaching the planets. On Earth, sunlight changes the speed and direction of winds through convection currents- air rises and falls instead of always blowing in one direction. Convection currents slow down the atmosphere. This is clearly true looking at other planets in the solar system. Jupiter and Saturn, which are also far away from the sun, have huge wind storms blowing across them. Other factors that also contribute to these planet's wind speeds include their hydrogen-rich composition which is much easier to move than our heavier oxygen and carbon dioxide. A big factor in these winds is also geological activity. Without much interference from the sunlight, heating patterns can speed up the wind to the hurricane-grade storms that you see on the exoplanets. The air starts spinning naturally either from the creation of the planet or form the planet's spin, and then geological activity in hot spots of the planet expand the air that passes by. Then the air radiates heat and shrinks again. The air that is now passing over a hot spot pushes on the cold air as it expands and gradually speeds up the air. Combine that with very little air resistance and convection currents and you can cook up some monster storms. That said, because we don't really know for sure how these storms form, any realistic answer is probably acceptable. [Answer] I wonder if tidal forces from a nearby large moon/planet could cause wind the way we get tides in the ocean from our smaller moon? Normally the smaller body (if this planet is a moon of a larger planet) would become tidally locked to the large planet and no longer have tides. However, this takes time, and your base might be on a recently formed or captured moon. In researching, "little sunlight" is a great deal more than no sunlight. For example read about Saturn's moon Titan. Titan is tidally locked to Saturn, so I can't get my gaseous tide question answered, but there are some other possibilities. While there seems to be little wind on the surface in general, there is quite a bit in the upper atmosphere. Also, when the seasons change from summer to winter, a large portion of the atmosphere moves from one pole to the other. While this is not a consistent wind, it could be harvested twice a "year", however long a year is. Links of interest: <https://www.sciencedaily.com/releases/2014/12/141208144406.htm> <https://en.wikipedia.org/wiki/Climate_of_Titan> [Answer] Geothermal energy On Neptune and Saturn, the strong winds are fuelled by the internal heat that is derived from their interiors. That is why Saturn and Neptune manage to pull up colossal storms despite being more than 10x further from the sun than Earth is. Create a chain of volcanoes across the planet, and you can get an heat differential that is enough to heat up the air to high temperatures, which can drive massive wind systems on your planet. ]
[Question] [ I wanted to create a constructed language for a species in my world that other people will be able to speak , but I have no idea where to start at all , and I am very confused. My Question is : what are some steps / guidelines for making a speakable constructed language? [Answer] On the internet exists a comprehensive guide to the construction of an entire language, appropriately named; [The Language Construction Kit](http://www.zompist.com/kit.html). I was going to copy/paste it but if I did, it would not fit! In the thousands of words it contains, you will find guides to sound choosing, word plotting, word formation, Grammar, writing systems and more. [Answer] ## It really depends on how far you want to go Do you want to create a number of believable sounding words, write foreign sounding sentences or construct a language very different from your own with its own vocabulary, grammar and history? All of these require very different levels of effort. At the very lowest level we have: ## Creating a naming language A naming language is simpy a number of coherent and realistic-sounding words with which you can name the characters, places and items of your world. A naming language has very little grammar, although you may need to distinguish adjectives and nouns. So how do we make it sound realistic and distinct from English? We start with a sound system, the core sounds of our language. A useful tool for transcribing sound systems is [the IPA](https://en.wikipedia.org/wiki/International_Phonetic_Alphabet). We'll start with [consonants](https://en.wikipedia.org/wiki/IPA_pulmonic_consonant_chart_with_audio): Consonants can be defined as on a matrix of place of articulation and manner of articulation. Place of articulation can be between the lips (bilabial), between the tip of your tongue and your teeth (dental), between the roof of your mouth and your tongue (velar), etc. Manners of articulation can be types of consonants like plosives (/p/, /t/, /k/) or nasals (/m/, /n/, /ŋ/) but can also be the same type but with a distinguishing feature such as voice (meaning your language would also have /b/, /d/ and /g/) or perhaps other features such as palatalization or labialization. What's important here is for that matrix to be mostly filled out. Every natural language has most but not all of its matrix filled out. Basically all natural languages have /p/, /t/, /k/, /m/ and /n/. In terms of [vowels](https://en.wikipedia.org/wiki/IPA_vowel_chart_with_audio), pretty much no natural language has less than /a/, /i/ and /u/, most have something like /a/, /e/, /i/, /o/, /u/, whereas some have a lot more. [This chart shows some good examples](http://gesc19764.pwp.blueyonder.co.uk/vowels/vowel_systems.html). Vowels may also have various qualities such as length ([which is not the same as "long" and "short" vowels in English](https://www.youtube.com/watch?v=nhOhZ5HSd54)) or nasality (like in French). These qualities need not and usually don't apply to every single vowel. For either, I think going onto Wikipedia and looking at the sound charts of some of the world's languages gives you a good idea of what a natural language does. Now, onto what really makes your language sound distinct: ### Phonotactics Every spoken language has rules as to what can be a word. That's why you'll register "trhnrbth" as just me mashing on the keyboard. Words are made out of syllables and syllables have structures whose rigidity depend on the language. Japanese, for example only allow syllables with either a single or no consonant as an onset, a vowel as the nucleus (center) of the syllable, and then it may only end on a nasal. That gives us (C)V(n) as our syllable structure. The more we allow into a syllable (something like CCCVVCCC, for example), the more rules we actually have to give to what is allowed to cross over. In English, for example, whenever /n/ is followed by /k/, it will be pronounced /ŋ/, because the two latter sounds are both velars and easier to pronounce together. Sounds may also merge into new sounds which only exist in those contexts. A good example is how "sugar" is pronounced /ʃөgә/ rather than /sjөgә/, as the /s/ and the /j/ merge into /ʃ/. --- If you set specific rules as to which sounds are and aren't allowed together in your language, this will make it distinct from other languages. If you're creating a writing system for your language, taking into account what your speakers percieve its sounds as will inform how it will be spelled. So if your syllables are restrictive, perhaps they would have a letter for each syllable, whereas if a lot of sound occur from merges of several different other sounds, perhaps it will be spelled as those original sounds together. The second level is: ## Creating a language with grammar Obviously, the easiest way to do this is simply to take every English word you're using in a sentence and make up a word in your language to replace it with. This is however not very interesting. What makes languages interesting is what makes them different from eachother. To start with, you need to define your language typologically. Is it analytic or is it synthetic? What these words really mean is if a language uses a lot of modifier words around the core words of a sentence or if it modifies its core words with affixes. English is a very analytic language whereas Inuktitut is sometimes considered polysynthetic: > > Tusaatsiarunnanngittualuujunga. - I can't hear very well. > > > Among synthetic languages, there are agglutinative languages, which use several single purpose affixes on words, aswell as fusional languages which use only one or two multipurpose affixes on words. Note that every language is part of a spectrum (not just squarely agglutinative) and that within every language there is a spectrum of functionality which resembles all of these typologies to some degree. After that, you have mandatory markings on words. English, for example, marks every noun with article and number. A word like "places" is in the indefinite article plural. Not every language marks number and not that many mark article. For verbs, for example, you could, along with tense and aspect (which English already does), mark [evidentiality](https://en.wikipedia.org/wiki/Evidentiality), whether or not the speaker saw what happened or heard about it. Looking through [grammatical categories](https://en.wikipedia.org/wiki/Grammatical_category) on Wikipedia is useful for finding grammars very different from your own language. --- The third level would be: ## Creating a language history Languages evolve from other languages and it shows. Usually, irregularities come about from various sound changes playing out. I've already written an answer on precisely this topic, so I'll simply refer you [there](https://worldbuilding.stackexchange.com/a/41673/20675). I will however elaborate on why this is even if you aren't going to reveal your root language in whatever you're showing your finished language. It clearly shows when a language has repetitive forms, which makes it more realistic. That those forms also aren't just the same ending tacked onto different roots, but is rather changed in some form, shows even more realism. Creating a language history also allows you to create dialects and language families really easily, as all you need to do is give them different sound changes from eachother. [Answer] This is an enormous cognitive-linguistic question. First you need to identify the concepts to be conveyed in language (see early cognitive linguistic development for spatial, locational, recurrence, etc., expressed in early developmental speech) Then you need a speech-sound system (phonemes: google this, and identify the speech sounds your language contains, and which other languages are in relation) Then you need to pick or form words, and a grammar or syntax for your language. Then you need to choose prosodic or sound-significance to the utterances of your language. Then you need to identify social communication aspects to your language: i.e. verbal language in dyadic relationship and the significance of linguistic and paralinguistic signifiers. Good luck, maybe watch Game of Thrones. [Answer] [Artifexian](https://www.youtube.com/playlist?list=PLduA6tsl3gygfiWmGAhhHb4-HAqP6I63l) has a series of videos that will walk you through the basics of starting a conlang. I also recommend [a certain other site's dedicated conlang forum](https://www.reddit.com/r/conlangs/) if this is something you really want to pursue (be sure to check their sidebar for additional help). [Answer] The best advice I can give you about conlanging is to purchase this book and read it like the bible. [The Art of Language Invention: From Horse-Lords to Dark Elves, the Words Behind World-Building](http://www.goodreads.com/book/show/24611649-the-art-of-language-invention) ![book cover](https://i.stack.imgur.com/Wzjhk.jpg) He goes into great detail explaining the finer points of what make languages realistic, but here are some of the highlights... 1. Realize that languages don't just emerge out of nothing. All languages (except for conlangs) evolve out of other languages. Do some research about ways languages organically change over time, and consider creating a "proto-language" before you create your final product. 2. The human mouth is capable of producing many more sounds than you are probably used to recognizing as an English speaker. Realistically, your conlang should utilize at least some phonemes that don't exist in your language and not utilize some that do. 3. All languages have rules about which sounds are allowed to go next to eachother. For example, in English we are not allowed to pronounce the letter p directly before the letter n. So when english adopted the greek word "pneumonia", we had no idea how to pronounce the first syllable, and simply dropped the p sound, but kept the spelling. (As strange as it may sound to us, the p is actually pronounced in greek. Their phonotactics allow for this consonant cluster.) 4. Don't just create a vocabulary and apply english grammar rules to it. Find some way to make the grammar of your language unique. 5. Most importantly... buy the book. I can't stress enough how useful it is. ]
[Question] [ ## Portals to Parallel Earths In this setting events diverge when massive breakthroughs in physics are made. The breakthroughs effectively prove the many worlds interpretation, but more drastically they allow portals to be opened to parallel universes. Other advances are made because of this knowledge but none remotely as significant as the portals that can be made. Events in this setting diverged very recently so other than the things caused by the portals and breakthroughs in a certain area of physics, things are pretty much the exact same as our world. ## Portal Specifics. Where the portals go: New portals connect to the equivalent positions in the parallel universe. New portals connect to worlds exactly the same as our own, however the instant the tunnel between them is opened symmetry breaks and random quantum events cause them to start diverging. It is of note that the parallel universe you just reached through a new portal, will have equivalent portals in their universe that lead to parallel versions every universe that your portal leads to. This means in addition to the portals that exist in a given universe every universe connected to also has portals connecting to parallel universes themselves. Thus the number of connected universes is actually infinite. Once a portal has been made to a another universe, the worlds are permanently linked. Future portals can be opened to that specific universe if you have the energy readouts from any machine that has opened a portal there before. If you can't obtain energy readouts from a machine you can obtain them by using specialized equipment on any area that the portal was near because of subatomic portals that occasionally still open leaking barely detectable energy, this detection equipment costs around a hundred thousand USD. Portals connect to the exact position in the other world. Portals can be moved but both sides of the portal are physically connected and can't be moved apart. Opening a portal between two preexisting worlds is impossible if there isn't a portal machine at the same location in both worlds. The portals can be made as small as 2 meters in diameter starting out at about 130 thousand USD, the price of a portal goes up almost linearly with the diameter of the portal, not with the surface area. The technology used will obviously remain unspecified, but it involves the use of small particle accelerators, as thus the machine and created portal tend to be circular. Note: While portals may cost upwards of 130 thousand USD the power requirements to open a portal and keep it open aren't very high, as thus you can pay to open a portal and pay a flat fee for however long you want to keep it open. Given the cost of opening a portal for a few minutes anyone can afford to do it. In this setting the oldest portals were opened by researchers a few years ago, as thus no worlds have had longer than that to diverge. The older worlds usually have diverged somewhat since opening. There are thousands of portals, just from the early scientific testing of this technology, and most of their energy signatures are easily available online, which means nearly anyone can travel to them. It is of note that some people may find due to the events diverging over a few years, that their double in a world is actually quite different, due to the effect of a random event in the time since they diverged. Economics: Given most of the worlds are so similar and the fact portals open to the same position in both worlds, it is obvious that most economic trade is pointless, because the worlds aren't sufficiently different. However, the one main commercial use for this technology (other than selling machines and portals) is taking advantage of having duplicate selves to perform larger amounts of mental work. For instance, scientists in different worlds may coordinate to run different calculations on supercomputers and then share their results allowing them to perform that calculation much faster. Entertainment may also become more competitive, worlds may decide to create different media, so that they can make material different than that of another world, afterward the different media will be shared between worlds. For tasks where the final result is information (which can have different worlds do different parts of the same calculation, or work on different things, then share the information) the production of that sort of information will become dirt cheap and there will be a far larger amount of this information. One example of an area where improvement should be expected to increase is animation. With thousands of cheap portals, a company can choose to do animation that would otherwise be slow with many, many portals each connected world can choose to only do a tiny amount of the total work and at the end they share their work with each other and each profit off the end result. The improvement made in animation is analogous to the improvements made in any mental task. Portals can never be made such that you can generate energy or decrease total entropy: The portals connect to the same point in both worlds so you can't use them to decrease travel time. The portals are supposed to be made using potential future technology and as such, aren't magic and are constrained by realism. Of course once we learn more about physics it seems unlikely we will find out we live in a world where this technology is remotely possible, but it still can't be completely ruled out. ## The Actual Question: With all of that in mind, what would be the large scale global economic effects of this technology? On the personal level the biggest effect will likely be using the portals to meet your doubles, but on the larger levels the main use of this is to perform utterly massive amounts of mental work and calculations quickly. What would be the effects of this technology be on the global level, how would this affect economies and governments? How would the fact that calculations and mental work could be done in massive amounts, in incredibly short times affect the economy. I think it's a given that many jobs will be cut. After all why have thousands of people do a job if literally one person can do it by collaborating with their doubles, provided they know how to do the entirety of the task. [Answer] I think that your statement > > Given most of the worlds are so similar and the fact portals open to > the same position in both worlds, it is obvious that most economic > trade is pointless, because the worlds aren't sufficiently different. > > > is incorrect. Consider two countries, on earth, with almost identical populations, economies, and infrastructures in which each has factories producing very similar goods. If there was free trade between the countries then the development of even a small manufacturing advantage in some product would mean that the factory with the advantage would eventually out-trade its opponent - so the symmetry in production would soon be broken. If there were many (or infinite) connected worlds then a similar process would develop. Say you manufacture pencil sharpeners - and via minor 'divergences' in production methods (or just dumb luck), you win a contract delivering sharpeners to a next world. Now you can bump up production and by economy of scale you can undersell all the connected world's pencil sharpener manufacturers. With an almost infinite market, you can set up mega factories making billions of sharpeners. Other worlds will grab the toupee market, the jam market, or the sports-car market. I predict that within a few decades this effect would lead to massive specialization where each planet would produce and export only a few products and import other goods from connected planets. [Answer] The types of uses of this technology fall into 3 classes: ## 1) Parallelization of Tasks As people have pointed out earlier, while you can't do everything in parallel, there are a lot of cases where doubling your workers and resources more than doubles your production, thereby allowing you and your parallel-universe-twin to split the resulting value and still come out ahead. An example of this would be a car company copying their prototype division and making 16 models in parallel. After testing, one of the models proves to be the best, that model is shared, and 15 out of those 16 copy-companies benefit from improvements to their design without any additional expenditure of resources (even the last one doesn't LOSE anything by participating in this and then closing the portals again). Parallelization could work well on smaller scales as well. Many simulations are massively parallelizable, and so supercomputers could be built which reap huge power boosts by splitting their computations between dozens or millions of universes, then sharing the results at the end. Two interesting sub-implications of this: * It is currently impossible to accurately simulate chaotic systems, such as weather, over long time intervals. However, an absurdly large collection of networked supercomputers could possibly manage it with some clever approximations ("absurdly large" as in one node per atom in the sky). This can be achieved by opening portals with low de-sync times so that it produces a hall-of-mirrors effect and spawns crazy-large numbers of universes very rapidly. Therefore, it wouldn't be too far-fetched to imagine that in this world, governments using parallel universe computing can figure out where to place proverbial butterflies so that their wing-flaps will change the winds and prevent billions of dollars in hurricane damage, for instance. * Graphics processing in personal computers is highly parallelized. I'm not sure what the physical limitations on portals are in this universe, but they may eventually be miniaturized into nano-portals that can be built into graphics chips. This would add improvements to graphics that's actually ridiculous, since it would scale as the exponent of the exponent of how many of them you could fit on a chip. Photorealistic graphics would be commonplace just a year or two after this extension of the technology hit the market. And that's not to mention other fields in CS that would love to have that kind of parallel scaling, like AI. I would be shocked if AI didn't make massive leaps forward in the years after this portal technology appeared. ## 2) Multiplication of Uniqueness If someone or something is one-of-a-kind, no matter how much you pay, you could never get more of them. Unless you had portals. For unique people, this includes uses like * Gathering 8 each of the world's top scientists to solve a crisis * Televising, live in 4 universes, the match of the century: 3 Lebron Jameses vs. 3 Michael Jordans in 3x3 basketball * Hearing the world's best violinist self-perform a quartet It also includes more clinical pursuits, like copying the same person 16 times and testing different medical treatments on them. The huge differences between the metabolisms of individual people would be a huge hurdle for medical science to suddenly overcome. Psychology and sociology can similarly tease out effects much more accurately - we'd be a lot more sure about whether subtle subconscious cues can change opinions if we could literally see the difference between the presence or absence of that cue in a single person. Other unique things we could replicate: * We could run twice as many experiments at the Large Hadron Collider if we doubled the universe and coordinated which experiments to do in each, then compared notes at the end. * We might be able to save endangered species if we could double their numbers in captivity and gather them all in one place (though obviously, this wouldn't help their gene pool at all). * If you're strapped for cash, crash at your parallel universe self's place for a week and put your place up on Airbnb (there could be severe market implications if it becomes too easy to do this). ## 3) Specialization and Trade As mentioned previously, two identical people or companies or countries in identical universes could specialize in different skills or products. Due to accumulation of knowledge and economies of scale, you could reap a larger-than-linear benefit for a linear increase in resources. How this applies to trade between countries is straightforward and has already been elaborated upon in other posts, but a related thing I want to draw attention to is personal specialization. It's generally much easier to learn from a tutor than to learn from a book, for instance. So just have 2 copies of yourself learn different skills and teach them to each other. I could imagine this revolutionizing education. So on the whole, people would have better computers, see more economic output in most industries, receive more effective treatments, etc. Basically, the pace of innovation would increase dramatically across the board. [Answer] This is less useful than you think. You're describing parallelization of tasks to make everyone more efficient. However, most normal tasks (especially mental ones) are not that easily parallelized. If you were familiar with Gantt charts you'd know why this entire exercise will be fruitless. For the case of your example, animation rendering, it's just not worth it. An animation company is not going to spend several hundred thousand dollars just so it can try to coordinate computer resources with its duplicate company. The rendering time is not the bottleneck and if they're going to spend that kind of cash they could simply buy more servers or rent server time. For mental tasks it's even worse. A human working on a problem is a very linear task. Think about any problem you've solved and I doubt you could have just as easily started anywhere in the problem and then combined the finished result. Think about splitting up to write your question, could you have jumped in at any paragraph and submitted it to your other selves to form the complete question? Highly unlikely. How about a larger task? Consider a company working on producing a more efficient and less expensive portal. There are a few phases to go through to get it done. For instance: 1. Design 2. Simulation 3. Prototyping 4. Testing 5. Manufacturing Those phases of the project can not be split up between identical companies across worlds. There is nothing to simulate until the design is complete, you can't test something that isn't built, and you can't start manufacturing until testing shows the device will work. Again, useless. As often cited, nine women can't make a baby in one month. --- The only benefit is going to come down to one world entity convincing another to give up some resources. Someone is going to get a better deal eventually and be in a better position to continue getting better deals. The worlds will continue to diverge and disparity will increase. [Answer] Economics of scale, but not only for intangible goods * new interdimensional gate 130k dollar * new microchip factory - ~2 bln dollar * new Boeign 737 - quote price ~100 mln dollar (presumably a bit cheaper after discounts) * high speed railway ~$25–39 million per km In price ranges involved those gates are dirt cheap. Yes, someone may point out that in few years one would not remodel the whole infrastructure... Sort of true... Just all future investment would include it. In case of air traffic it would be immediate revolution. Building a few dozen gates would mean that there would be enough air traffic. In our world there is not enough traffic between city A and B to keep regular flights. But if one can gather all passengers from cities A[1-10] willing to go to B[1-10] you can stuff whole biggest Airbus. Perfect, new route. Even for already profitable routes you can push passengers through gates and increase utilisation. Bad weather in one of the worlds? No longer an issue. Using google route finder to get in to interdimensional travel would be fine. Oh, by occasion, tourist often wouldn't even have to get to the right world. Seeing parallel Paris, as long as credit cards are accepted, should also be fine. In RL world high speed railway often ends as flop because of lack of passengers. Retouring people from a dozen of worlds should suddenly solve this issue. [Answer] Well, the exact magnitude of the economic impact would depend on the scale on which these portals would be built, and who would have access to them. The implications of these things are incredibly complex. Parallel worlds are mostly very similar to ours. That means that the military could potentially test out political and military scenarios in one of these parallel worlds, in order to determine their actions' impact on the economy/politics. They could easily open a portal, drop a tactical nuke - or some other devastating weapon - on a city/fort/military facility, then send special forces teams to extract gold/information/weapon designs/etc. The scenarios are literally endless. The government wouldn't care, as it would be the United States in the other universe who would pay the price for their actions. In the mean time, they now have solid intel, or incredibly valuable information, etc. which is completely applicable in their own universe. Alternatively, imagine the two countries from parallel universes cooperating. The US military sending massive waves of troops/planes/ships through the portal to help the *other* US absolutely obliterate their enemies, and then having them return the favor. The first country to think of that one may very well rule the world (both of them) And now, you see how dangerous this tech is. Depending on how it's used, and by whom the world as we know it may very well cease to exist. And so, I don't think that I can answer your question in exactly the way you've asked. All I can say is that the impact on the economy is going to be *huge, however you have not provided all the data to determine whether in a positive or a negative way. [Answer] Genocide is profitable* So you have an identical worlds with identical resources populated by identical people. Now if you had an identical world with identical resources, that would be much more useful. All you need to do is get rid of those pesky people besides who would miss one planet of people in an infinite multiverse. Only catch with this thinking is if another universe has the same idea so you really need to guard against someone opening a portal to your universe and doing it to you. Sure this is as ethically as black as it can get but there are corporations and governments in the world who would do this in a heartbeat. Just think of the oil, gold, mineral resources you could get, not to mention the perfect prison planet, toxic waste dump, ethically abhorrent research lab or environmentally damaging manufacturing plant. An empty world has infinite value once you get rid of a few pesky native. It's morally abhorrent but there are people in the world who would use it this way. [Answer] Who are you ... but actually Do you and you twins from different worlds trust each other or commit massive identify theft? Then ask the question again for companies and countries. We could see large scale power blocks as people ally with their twins to do great or terrible things. Who would you trust more than your exact clone, but who knows better how to fool you? It would seem the wining strategy for each cooperating collective of twins is to diversify their choices as much as possible to increase the chance that any one has huge success. This would tend to drive divergent evolution of worlds even faster. We could see huge economies of scale in tec and research as the research from one world can be shared with the others for free, and some planning keeps us from duplicating research. There also would be so much more knowledge available because we could to completely controlled experiments, on whole cities and planets. [Answer] What I found interesting about this question is that the number of connected worlds grows exponentially. The first world A, comes A = A when the first portal is created, and after they diverged AB = AC with the identical time lines A and divergent time lines B and C. With second gate AB=AC becomes AC=AB = AB=AC, which then diverges to ACD=ABE = ABF=ACG. And so on. This has two interesting things about it. First, the growth is exponential. The amount of worlds is 2N, if N is the number of gates. Second, it is actually the number of unique time lines that doubles. At first sight it would seem that only the world with the new portal gets a diverging copy but actually all the connected worlds do. So it could be argued that this is not really a portal. It is a world doubler. And a dirt cheap one at that. The economic effect of this would probably be stability. Let us assume a small event such an officer handling the Russian nuclear weapons drinking way too much and setting out to prove that he can indeed circumvent all the security measures and launch all out nuclear assault without anyone being able to stop or abort it. Normally this would be fairly disastrous. Even if you are not in where the Russian nukes fall, it seems unlikely the Russian would be able to convince the US and China that it was just too much vodka causing all those nukes and there is no need to counter-attack. Honest! So lots of pretty fireworks. And fallout and nuclear winter and all that. But if we assume the world had the portal tech and a modest number of gates, say 8, less than half percent of people would be directly affected. Maybe, probably, the nukes would break the gates and the world would be cut to segments that cannot get reconnected. But even that is unlikely to be significant. One world just is not that important here. And even if it was the segments would continue to grow exponentially. And given how cheap the portals are 8 really is unrealistically low. It is more likely every world would have hundreds of portals. So even a nuclear apocalypse would be too small to make much of a difference to the whole. And if we assume more realistic numbers of gates some of them would survive even the nukes. And survivors near a gate could just go into another world where everything is just fine. And there they could spread to an infinite number of worlds, so the number of refugees per world would be pretty low. So the portals would give us an exponential amount of redundancy and mass to absorb any negative events. It would also give us an exponential amount of information. Since every time line is actually truly unique we are not just doubling same old information, we are doubling the new information. Naturally much of that will be duplicated and redundant. But even if we assume that people make no effort to avoid duplicated effort, exponential growth is really scary. Assuming one percent chance of new idea being non-dupe, which is probably unrealistically low, the amount of available ideas would still be multiplied if the number of gates is as large as we'd expect given the low prices. And honestly I do not think the universe is deterministic enough to keep that uniqueness down to single digit percentages. Certainly under the premise of this question it could not be, otherwise the worlds would not diverge and the portal would be an expensive vanity mirror not a dirt cheap world duplicator. And naturally people would actually take efforts not to duplicate work. Why should everyone make this experiment when we know the result in one world will be valid in all? And that the rapid growth of the network pretty much guarantees somebody will be making the duplicate test anyway, so there is no reason to duplicate work on purpose. I think this is about what can be deduced here. There are lots of interesting questions about how people and governments would react to all of this. With lots of options. For example, world growing at an exponential rate would be very difficult for everyone to comprehend, this might lead to rise of populism and anti-elitism as people look for safety in the simplified and familiar. People might turn to religion or away from it. People might go for aggressive economic strategies to get maximum benefit from the opportunities or conservative ones because there is no longer real need to compete with exponential growth. And eventually how various people solve these questions is what would determine the specific changes. And every world would be unique and divergent. Note that even if a world stops making gates or goes all out to make as many gates as it can, all worlds get duplicated equally with every gate. Even if you destroy all your gates, there would still be lots of shards with worlds that differ from you in only not actually pulling the trigger. But I feel those are about actually building the world and no longer about answering this question. [Answer] # Cold War dynamics and heavy regulation of incoming portals I will focus on effects on governments because I think it is the most important question by far. In my view, a zero-sum-game dynamics would quickly unravel unless you have a cheap way to block incoming portals to your own universe. John von Neummann, a pioneer in game theory, came up with the Cold War strategy of [Mutually Assured Destruction (MAD)](https://en.wikipedia.org/wiki/Mutual_assured_destruction#Two_Doomsday_Devices), a strategy in which > > each side has enough nuclear weaponry to destroy the other side and that either side, if attacked for any reason by the other, would retaliate with equal or greater force. The expected result is an immediate, irreversible escalation of hostilities resulting in both combatants' mutual, total, and assured destruction. > > > Therefore: > > neither side has any incentive to initiate a conflict or to disarm. > > > The problem is that in your framework there are infinite sides in conflict, not only two!! In this game, every universe has a huge incentive to form a coalition and attack another universe whose resources would become available to the members of the coalition. But people in the other universes know this (there is a Jon von Neumann in each universe!). Therefore, each universe will try to: 1. Prevent others from attacking. 2. Form a coalition and attack first. This is a highly unstable situation and no universe can be sure there are no plots against it. If universe A and B start a plot against C, A cannot be sure that B and C are not planning a plot against A. The same goes for B, and so on. Since the number of universes is infinite, the number of possible coalitions is infinite and the situation becomes rapidly unmanageable. If your coalition strikes first you might get an actual chance of a) making a profit out of it and b) survive. This [movie](https://en.wikipedia.org/wiki/Coherence_(film)), in which people meet their other-selves, is an example of the kind of things that could happen when parallel universes are available to humans. The good news is that every universe knows this too!! So the one strategy that leads to increased stability is to devote resources to monitor incoming portals and develop defensive systems against them, just like countries do today in their borders. In addition, portals would have to be heavily regulated not only due to military strategy but also to prevent trafficking, smuggling, etc. You can hide drugs in the alternative universe in your basement and viceversa ad infinitum. Moreover, if you kill someone in the alternative universe, are you a criminal in your own universe? What if John from universe A kills Sam from universe B and John from B kills Sam from A? What if you kidnap people from the other universe? [Answer] Looking into the logic of the question as asked, and looking at the salient comments to it - I see only one outcome. The first time that one opens a portal to another parallel world - according to the rule that until a portal is opened, there is no divergence, thus, when a portal is opened to a world, the equivalent person on that world is opening a portal to a world on which the equivalent person is opening a portal rinse & repeat. When the first portal opens - an infinite number of worlds springs into being - according to your specification in the question apparently you have the address to all of these? How big is your address book? On your hard drive? What you have is an infinite number of universes, with an infinitley massive hard drive. In each. Each and every universe collapses upon its'self from within it's Hubble horizon creating a supermassive blackhole billions of times larger than any seen since the last civilisation tried this. Noone makes any profit, except the hyper-dimensional gameplayers who made bets on whether they could trick you into doing this in the first place. [Answer] No one is taking this to the logical, horrific end The first nation that discovered the tech would basically have to conquer the world. Some other answers are postulating that different Universes would compete with each other. Why? The mirror USAs or Mexicos or Germanys would have way more in common with each other than the other nations of 'their' worlds. So I think something much worse would happen. Here's an example. North Korea gets the tech. Kim Jong Un decides he wants to ally with his counterpart. They open a portal to another, virgin world. Suddenly, they have two North Korean armies. Each North Korea secretly built a single medium range nuke missile, and has a single sub to deploy it. They each have ten transport ships, and a couple million conscripts. Then they open another portal. It's only $130,000 American, so doable. Now they have doubled. Then they do it again. Another doubling. And again. And again. And again. It takes a week, they ally, hash out an order to conquering their home dimensions one after another. Each Kim Jong Un gets their earth. All of a sudden 16, 32, 64, 128, however many subs that original Earth doesn't know about, because their Norks only built one - launch their nukes at US navy assets. 150 million Nork conscripts sail for the west coast. There simply aren't that many assets to stop them. The Nork Portals are on a different 'tree' of dimensional portals, so no one can warn them. Any portals you open have already suffered this Alpha Strike scenario, so you can't do to them what they did to you. Now imagine the preceding scenario, except it's Russia. Iran. China. America - presuming they are first in discovering this - or the EU would have literally no choice except preemptively taking over the planet and reducing everyone else to the point where they couldn't even attempt such an alpha strike exploitation of the technology. ]
[Question] [ Note: I'm working on a far future sci-fi setting for a novel series which aims to blend elements of both "soft" and "hard" science fiction concepts. I'm aiming for the series to be as grounded and consistent as possible whilst still allowing some elements of speculative physics. Most places in the galaxy are well within a post-scarcity economy, and any group or in some cases individual can afford a fleet of automated construction and mining drones if they so choose. Stellar and planetary scale megastructures are commonplace, up to Dyson scale and in some cases even larger. The seedy capital of a region of lawless space is a tower almost 5000km tall built on an Venus-mass planet in the outer regions of a star system (not a space elevator). The tower, which we can provisionally call the Spire, was originally intended to be constructed to geosync orbit, but events in the distant past led to the abandonment of the tower and its subsequent takeover by criminal/corporate groups. The tower has a base 100 kilometres wide and makes use of active support and materials such as carbon nanotubes in its construction, and has a population in the hundreds of millions if not low billions. Much of the internal volume of the tower is given over to vacuum train tubes intended to bring cargo up and down the Spire. The planet's crust is robust and geologically dead. Having recently come across an interesting Isaac Arthur video on super tall space towers (up to geosync, using active support and carbon nanotubes), my question is that would such a tower like the Spire be feasible with access to these technologies? Many thanks! Note: In this context, active support or an active structure is referring to the use of a constant stream of matter (such as iron ball bearings) to impart momentum within a structure to provide support, as in the concept of a space fountain. The main advantage is that this allows for very large structures without relying on compressive strength, with the main disadvantage being that constant power is required to maintain the matter stream. Note 2: The tower serves as a kind of "neutral zone" for these groups, which largely self-govern themselves such as historical pirate enclaves, havens etc. Any form of combat within the vicinity of the tower is strictly forbidden and harshly dealt with. [Answer] ## Not possible For every action, there is an opposite and equal reaction. The surface of your planet could not endure the reaction force of your active support system. All of the force you exert upwards to keep your tower from crumbling under its own weight will also exert a downwards force. When solid objects get into the scale of thousands of km, they stop acting like solids and act more like fluids. Your tower would quickly sink down through the crust, burying itself in the planet instead of sitting neatly on the surface. If we assume your tower has a roughly conical shape (the best shape for making a tall tower like this), then it will have a volume of about 39,300,000 $km^3$. Office buildings made of traditional steel and concrete have a density of about 350 $kg/m^3$. Using carbon nanotechnology, you can probably get about 5-10 times as much compressive strength for your mass as a high-end concrete and steel constructed building. So, let's say your tower probably has a density of about 35 $kg/m^3$. This means that its total mass is about $1.3755 \times 10^{18} kg$. The base of your tower is about $7.8540 \times 10^9 m^2$, meaning that the base of your tower will exert a downward force on the planet of about $1.5534 \times 10^9 N/m^2$, based on Venus's gravity. Most natural stone has a crush force of about $1.8 \times 10^7$ to $6.7 \times 10^7 N/m^2$ depending on its composition. When you exceed this force, the ground will behave like a liquid, letting your tower freely sink into it. In other words, your tower is about 23.1 times as tall as the crust of a rocky planet could theoretically endure. Probably closer to 40-100 times too tall when you consider the weight of the things inside your tower. So, if you want to go for scientifically believable, about 50-200 km is about how tall you can make a tower with that base to height ratio. Even if you make room for massive improvements in building materials, the ground you build on is not getting any better than it is today. This gives you a few options: 1. Make your tower MUCH smaller. Works, but also boring. 2. Give your tower a "root structure" that gives it contact with about $3.2 \times 10^{11} m^2$ to $7.8 \times 10^{11} m^2$ of ground for the active support system to push against. Kind of a neat solution, but frankly still does not address the issues brought up in [lupe's answer](https://worldbuilding.stackexchange.com/a/248731/57832) 3. Give your tower a MASSIVE subterranean empty space so that it actually floats in the solid rock of your planet following the principles of buoyancy... though this will violate some serious material integrity principles which will need to be solved separately. 4. Hold up your tower using science that does not presently exist. This can be done by either making it out of some unobtanium allowing you to solve for the problems in #3, or use something like anti-gravity to negate the effects of your tower's weight on the planet. This is probably your best solution because it is the least contestable in the case of a bad calculation or overlooked limiting factors while still making your super tower a possibility. Also, you have described your tech level as being a highly advanced K2 civilization. They SHOULD have all sorts of technology that seems borderline magical to us. You can't conceivably advance that far and not invent stuff that flies in the face of our current understanding of science. [Answer] # You're going to have a killer maintenance schedule And, by that, I mean lack of maintenance is likely to kill everyone on the tower. Assuming the base is made larger, as @Nosajimiki points out, the next issue is that active structures need everything to keep working. Imagine, if you will, the number of times power has gone out in your building. Now imagine if any time this outage lasted for more than a couple of hours, the building would fall down. Now fill the building with pirates. If the power goes out longer than the backup power lasts? Everyone dies If the backup power generators/batteries break? Everyone dies If the HVAC system breaks? Everyone dies. If the magnets at the top to redirect the ball bearings break? Everyone dies. Some by ball bearing grapeshot, others by crushing, some because a stream of ball bearings neatly sliced the bit of the tower they live in off If the cooling system for the magnets breaks? Everyone dies. Some by ball bearing, crushing, etc, some by fire, superheated magnet coolant and minor explosion. If the airlocks, walls etc break anywhere from kilometre 9 and up? Everyone dies. The other charming feature of this kind of structure is that failures tend to compound. If a magnet at the top breaks, the ball bearings are likely to puncture a whole bunch of important electronics. Same with the magnets at the bottom. A loss of vacuum in the ball bearing tubes would lead to a mass of red hot ball bearings not quite making it to the top of the structure, before jamming somewhere and causing additional breaches. You might have a fleet of automated constructor drones, but when some drunken moron in a tricorn hat uses them for target practice, who is going to fix the critical power conduit damage on sector 5 caused by the exploding space-meth lab? Where do they get electronics they can't make? Raw materials? Keeping an active structure running is a tough task for a functioning government. Make it some sort of space tortuga, and everyone will be dead within two weeks. Incidentally, this is the kind of thing stopping us from building an active structure/space elevator. We probably have the materials to do it, power could come comfortably from a few dedicated nuclear power stations, we make some great magnets. But if it cuts out, it kills everyone in a neat line from the tower base Edit: I think I'd agree about the tech level meaning these challenges have been solved, but, most importantly, no one would be building active structures if you're at that tech level, because to get there you'd need materials that are strong enough to straight up build a tower, or some way of screwing with gravity. You're not going to mess around with a structure whose primary failure mode is to spray red hot ball bearings through the living quarters and then collapse. [Answer] @Nosajimiki has a point; your tower is impossible as written. To get around it, you need your active support to come from a far wider base than just the 100 km square area you are talking about; it needs to come from a far larger base, perhaps 500 km square; so the down thrust needed to create your active support presses against a much wider area. Perhaps you can discover that your spire is just part of a much much larger underground pyramid, completely occupied by the machinery needed to provide the active support, in fact ultimately the tower does not rest on the crust at all, as it appears, but goes down another 1000 km to rest on the hot mantle of the planet. If you want, that heat can also be exploited to power some of the active support; the pyramid is a geothermal machine. [Answer] A few ideas: The planet is a huge diamond Estimates for compressive strength of bulk diamond range from 3 GPa to 100 GPa. These are above the 1 GPa load at ground calculated by Nosajimiki. Apparently [planet sized diamonds](https://www.nationalgeographic.com/science/article/diamond-the-size-of-earth) are not entirely unrealistic. Relativistic ion motors for active support Send a constant stream of water to the tower at low velocity, wide pipe. Use electricity to accelerate water molecules to near light speed before ejecting them downwards. This way the base does not have to bear the weight of the tower. The energy requirements are pretty huge. For relativistic ion motors, thrust force approaches F = P / c as the ion velocity nears the speed of light. If we take the 10^18 kg mass estimate, this would take 2700 yottawatts to support, whereas the Sun's total power output is just 400 YW. A planet with lower gravity would of course make it easier. This does cause a lot of radiation to wherever the matter beams happen to hit. It will also slowly use up the world's oceans, though with efficient enough ion motors this could take millennia. Fast spinning planet has low geosynchronous orbit If the planet had rotational period of 3 hours or less, the 5000 km high tower would go past the geosynchronous altitude. The mass could then be hanging from cables, like a normal space elevator. ]
[Question] [ In [this question](https://worldbuilding.stackexchange.com/q/25206/75), I detail a world with a third human sex, lilim, who have bat-like wings and taloned feet like a bird's. The TL;DR is that lilim give birth to equal numbers of men, women and lilim (and early-miscarried male lilim), while women give birth to only men and women. Lilim are a female sex. The issue is that given that lilim have slightly lower birth rate than women, and only 1 in 3 births is a lilim and 1 in 3 is a woman, while half of the offspring of women are women. Going by pure genetics without considering selection pressures, lilim are doomed to becoming extinct or a minority curiosity. An additional complication is that until the age of between 6 and 9, a woman-child and a lilim-child are indistinguishable. However, lilim aren't willing to just sit back and let that happen. On the world to which lilim fled after it became apparent that their sex would become extinct on our own world, there was a war between the Vilifiers - lilim who vilify women and advocate preventing them from reproducing, and the Nurturers, who couldn't stomach the wholesale sterilization and/or murder of a third of the population. The result of the war was that the population separated, with the Vilifiers on the original world and the Nurturers on a new world. I'm sure that we can imagine the sorts of atrocities that a people at war with their own genetics could perpetrate. However, I'm interested in more subtle methods of controlling the population of women that the Nurturers might practise. The Nurturers are still lilim, and are still not willing to allow their sex to become extinct, they just have more scruples. So, the question: How might lilim reduce the rate at which their woman-children reproduce without denying them the opportunity to reproduce at all, with the most effective and least intrusive, cruel or obvious methods being preferable. Edit: Religious solutions are not acceptable. Their society rejected religion at a particular point in their history prior to the Vilifier/Nurturer schism. I'm looking primarily for psychological, sociological and legal solutions. Technological, magical, surgical or pharmaceutical solutions are also out unless the women voluntarily have themselves sterilized or use birth control, the Nurturers feel that such solutions are a step too close to the practises of the Vilifiers. Any such solution must be voluntary and not coerced at a personal level. The lilim understand Mendelian genetics, but are not capable of genetic engineering. Edit 2: To bring the genetics in from the linked question, men have X and Y chromosomes. Women have XX. Lilim have LX. LY male lilim offspring do not implant into the uterus, and so is lethal. Viable LXY male lilim occasionally occur, but are not genetically significant, as they are sterile. Also, for the sake of evolutionary history, before Adam meddled, Women had WW chromosomes, men were WY and Lilim were WL. LY was still lethal, as were WW women-children when they were carried by lilim. Women became extinct due in part to the higher survivability of lilim. Then Adam changed the W chromosome in men to X, and added selection pressures which led to the elimination of the unmodified W chromosome. [Answer] ## Small frame-challenge beforehand Saying that the population is doomed is kind of an over-extent. Indeed, lilims would be a minority, since regardless of how you plan things, they are mathematically less or equal in numbers to men and women by being only 1/3 of the people. But evolution just doesn't work in a "they exist or go extinct", it's a gradient which balances naturally itself out. The real issue to my eyes is that for your lilim to continue existing, they need to overcome their poor ratio of 1/3 lilim every birth. In our world, a population is considered stable if each woman has at least 2 children in order to replace mommy and daddy. For your lilim's case, they would need to have 3 children at least so that on average, 1 is a lilim who can perpetuate the legacy. This could be done by various, society-wide changes (lower life level, culture and traditions...). However, increasing birth rates plainly in all the population is not what you ask for visibly, so we'll focus on adjusting the gender proportion in the society, ie. less women, more lilims instead. ## Answer : Alter gender images and roles, create a new "nobility" Now, supposing the birth rate is naturally high enough, how can we increase the proportion of lilims in society? Lilim's infantilization of their rights like what women suffered in old times could be a possibility, making them the gender to "take care of house and children" (and thus, make children). However, I think it's much more efficient to glorify the lilims -think old Nobility- and create strong genderization in the society for four main reasons : * First because it's much easier to find positive traits than negative traits about people who can fly and traverse worlds -I skimmed your old question-. Having such abilities make them look "better", even if they don't use said qualities everyday. What's important is the picture people have. * On the reverse, making lilims only good at "making children" is very, very likely to reduce their political and social influence. As a lilim you don't want to lose control when you're already few and want to influence society to stay afloat. * Then because it'll socially protect them more than other genders, meaning more help when in case of trouble, and first ones out of conflicts. * Finally because we have to remember that men-to-women/lilim ratio is lower than expected, comprised between ~50% (case only women had babies in the previous generation), and ~67% women/lilim-to-men (->only lilims had babies). So there's more women/lilim candidates than men. The choice, even more so than most real-world societies will be up to men. Advertising lilims increase the likelyhood men will find them attractive, making lilim/men couples more likely than women/men's1. As such, lilims will have more value as wedding candidates, with women coming only second. Because (or therefore?) lilim give birth to 67% higher-valued persons (sexually-valued men and glorified lilims) instead of 50% for women, lilims also become de facto the best choice as wedding candidates when looking only at numbers. This will in turn change culture where lilims are the "wifes to get", and women will be more strongly educated and enticed to have "worker-ants" roles in the society instead. Glorifying lilims is a pretty straightforward job : Prioritize lilim-only sport-events -ideally at things only them can do-, make them the main actor-ess in movies, expose great lilim explorers, artists and scientists in museums, take high political positions and so on. This can be done even without the numerical majority. For genderisation, do like old societies : gendered schools, strong gender norms, pressure to "fit in the mold"... Just go gentle and sneaky with changes or else other genders -'specially women- will react and strifes can happen. And if you think ahead -and subvertly- about the eventual overpopulation2, institute a law which penalizes having more than 2 children. You can officially state population's stability is ensured, and at the same time "discarding" women first for having lower value. If not by IGVs and child abandon, by lower education and all subsequent issues (lower lifetime, less chance of finding men, higher-risks jobs...). --- 1 : You could think polygamy is an alternative, but... It doesn't change the ratio men will look for lilims, it only spreads men on two genders with two opposite gender ratio directions. 2 : 3 children per Lilim means that your population will grow, even if women are a minority in dating men (you only need 2 to reproduce, while you produce 3 to perpetuate, with one producing "byproducts"). This will always lead to some overpopulation eventually, with its issues like wars for ressources. Fortunately if treasured your lilims should be the first one out of danger during those kind of things. [Answer] Child support for lilim big enough to not work, only make babies. Any lilim will get support for their child until age 9 or until maturity if the child is lilim. Regular women do not get child support. Result–Lilim will have lots of children where 1/3 will be lilim. Normal women do not have money to rise children if they do not have a partner who helps. Disadvantages–kids with male/female gender after 9yo can be abandoned by lilim mothers. Some lilim will make making babies their way of life, having 20-30 of them and rising only lilim to maturity. [Answer] # Sexual freedom and abortion Woman are classically thought of as needing to select their sexual partners carefully. They need to be sure that they get the best seed and that their kids, as well as themselves, are cared for. Lilim will not have those luxuries if they want to stay relevant. The advantage is that they live in a society. With the right push this represents they can get much more cohesive, allowing better distribution of wealth and care between the Lilim. As care for themselves and kids is dealt with they they can have a much more sexually free (sub)culture. They can still have fixed partners, but it isn't required. Lilim can thus be much more promiscuous as the threshold to get kids is much lower. Now imagine a society where woman still act as they do on Earth and all their cultural and personal differences. Now add a second group of ultra promiscuous women than are generally very much ok with unprotected sex and in many cases will take care of the kids if any arise. The rate of men 'getting lucky' at the end of the night goes up, the amount of pregnancies of Lilim will go much higher than normal woman. ## Abortion There is still one difficulty. Even at the best times a 1/3rd is expected by the law of big numbers. That is if only Lilim get pregnant. The trick is during conception. At several intervals you can check the DNA of the baby. You can choose to abort it if the DBA is himan female. If the difference of Lilim and woman isn't visible in the DNA it can only be an environmental trigger. This triggers gene expression into woman or Lilim. If it is an environmental trigger it can be controlled. [Answer] Compulsory childbirth for Lilim. In this world, fertility has fallen. Millions of individuals and families wish to adopt and are in demand for a child. In this world, the domestic supply of infants relinquished at birth or within the first month of life and available to be adopted has become virtually nonexistent. It is in the interest of the state for the population to grow and because 2/3 of Lilim children can themselves have children (as opposed to only 50% of children to human mothers) it is in the interest of the state to compel Lilim to bear more children. The system will be analogous to a draft, which historically required males to give the use of their body for some years to the state, to be used for military purposes. Lilim will likewise be compelled to give the use of their bodies to the state for purposes of bearing children who then will be made available for adoption. Of course it is only just that if a Lilim who is compelled to bear a child wishes to herself raise the child, that will be allowed. Taking the choice to bear children away from Lilim (for a short period) will result in more children total and necessarily more Lilim children. This advances the interest of the state that the population grow and that adoptions of non-domestic infants be made unnecessary. In this democratic society, the factions who feel the reproductive draft is unfair are balanced by the factions of those who wish the long term preservation of the Lilim type. [Answer] I Have a solution for the Lilim extinction problem, which simply involves some policies. There will be no need for any war or sky-portals to an exoplanet. But, the solution does rely on 2 kinds of Lilim. One set seemingly will be more socially dominant than the other, but that will be a later discussion. I have made population simulator with time using Python, and implemented policy decisions in form of modularized code. In order to simulated the effect of policies practically, I have used some heuristic models, which work quite well. I have results to show. Basically, I have been able to achieve multiple scenarios, in which the percentage of each gender in the population finally achieves a stable percentage after a number of epochs, and remains the same for remaining epochs. This constant state is achieved at around epoch 40. In one of these, the final unchanging percentage of men is ~41, women is ~32 and Lilim is ~27. To understand the policies, one must first understand these terms: 1. `lilithPref` : The percentage of men who prefer Lilim and are going to marry them if any are available. 2. `polyPref` : The fraction of Lilim who practice Polyandry (Female Polygamy), as is required by the law for certain number of Lilim to be *alawys* married to as many partners as is prescribed by law. 3. `polyNumber` : The number of husbands Lilim who practice polyandry can have. Everyone else in the population can have at max 1 partner *only. 4. `deathToBirthRatio` : I am using 0.4, which is close to current global average. 5. The simulation starts with an initial number of 50 men, 25 women and 25 Lilim in the world. Feel free to try different seeds. 6. `epochs` : The number of epochs for which the simulation was run for each set of unique parameters is 100. 7. `total` : The total population at the end of 100 epochs. 8. Also, unfortunately, all Lilim who are following polyandry have to discard their women children. This will be more easily done if chromosomal testing of the fetus will be legal, but there can be other solutions as well, such as disallowing female children of Lilim from giving birth, so these women are not accounted for in this simulation. Probably, these women will finally end up being Amazons and leading society ? Monogamous Lilim do not have to do this, and are strictly prohibited from doing so (Treating their women-born any differently). The graphs below show results of different policies. The calculations omit exception LXY beings (they are basically counted as men, although in reality, they will be able to contribute lilim offspring as well). 0.33 of the offspring of Lilim are of each gender, and 0.5 offspring of women are men and women respectively. First, the men who marry Lilim, including the polygamous Lilim are accounted for, then, the remaining men marry as many women as are available. All of the parameters are taken into calculation. The new generation comprises men and women from both Women parents and Lilim parents, substracting the women born of polygamous Lilim, and the lilim come of course only from Lilim parents. In each epoch, the total number of (cumulative) existing men, women and Lilim participate as parents, and after the epoch, the new generation has m new men, w new women, and l new Lilim. The number of total men, women and lilim are then updated to: `men := men - deathToBirthRatiom + m` and the same rule applies to women and lilim. 1. Men Domination: [![This appears to be the best policy, since lilim do not dominate but are nearly 25% of the population](https://i.stack.imgur.com/X4Bc0.png)](https://i.stack.imgur.com/X4Bc0.png) This appears to be the best policy, since lilim do not dominate but are nearly 25% of the population 2. Women Domination: [![This is unsustainable, since Lilim drop to 0](https://i.stack.imgur.com/YUIBe.png)](https://i.stack.imgur.com/YUIBe.png) This is unsustainable, since Lilim drop to 0 3. Lilim Dominance: [![Here, the Lilim dominate. Even this is sustainable, but seemingly dystopian](https://i.stack.imgur.com/IV6nJ.png)](https://i.stack.imgur.com/IV6nJ.png) Here, the Lilim dominate. Even this is sustainable, but seemingly dystopian Do feel free to make experiments of your own. I think that this adds a good flavour to world building. It is to be noted that I have used heurstics such as epochs here, but this adequately models the real world, although in the real world, the coefficients used would be exponential, there will be many more variables, and everything will be continous (hence requiring calculus or functions to model). [Answer] ## Your lilim are a dispersive morph, which means they are widely recognized as vital to the human ecology. It is unusual for mammals to do this, but [naked mole rats have a special dispersive morph](https://www.researchgate.net/publication/14598812_A_dispersive_morph_in_the_Naked_Mole-rat), which is to say fatter mole-rats that seek out reproduction with other colonies. The evolutionary logic is clear: ordinary women (who might even, by analogy with termites, be considered supplemental reproductives) are competing with each other to pass their genes on in the local environment. But on your planet it is for some reason very important to get genes to spread long distances. Hence the lilim, and especially, their wings. Nothing shouts "dispersive morph" louder than an improbable set of wings! The scenario for this in the other post looks creationist and magical, but a world from before the Sun and Moon might work much like a tidally locked planet around a red dwarf, with many isolated valleys at the twilight zone heated partially by geothermal sources. The valleys periodically change temperature, water availability, and exposure to X-ray flares. Populations who have lost genes needed to resist radiation or other extreme conditions will inevitably die out. But there are also important genes local to any one valley regardless of weather conditions - resistance to arsenic or boron, for example. Your lilim evolved in order to ensure that every population receives a certain minimal level of genes from outside their comfort zone, meaning that they are well-poised to adapt as conditions change. (They still would need several generations to adapt to avoid being bottlenecked down to a few individuals) Because the lilim bring "bad" genes poorly suited to a population, they might be seen ("Vilifiers") as a eugenic threat to the population, inflicting suffering on offspring who are constantly shivering or disfigured with hard radiation-resistant cuticles. They themselves have a broader view that comes with travel, and understand themselves to be an essential part of their people's ecology. In the long run, communities which reject the lilim and drive them off will die out. It may take hundreds of years before well-deserved disaster strikes, but "Nurturers" would be expected to call it justice when it does. Clearly, the death of entire lilim-free communities and their replacement from scratch by lilim colonists will reduce the non-lilim reproductive rate. However, it is also possible for "Nurturers" to cause women to accept that a certain fraction of births from their community must be lilim, in order that its genetic heritage passes on to the rest of the world, and that women should forego pregnancy whenever their community is deficient. [Answer] "The issue is that given that lilim have slightly lower birth rate ... lilim are doomed to becoming extinct or a minority curiosity" - nope. Evolution works like charm on animals but not on people. Take medicine. Specimens who would inevitably die are cured and keep living. People do evolve but they do so very slowly and without any drastic changes. Lilim are not doomed. Considering they were part of humanity for hundreds of thousands of years and survived the worst - famine, ice ages, epidemics - there is not even a slightest chance for them to succumb to evolution pressures when people reached other worlds. There are none. They are firmly part of humanity. Usual societal defense mechanism would work - "do to others whatever you would like them to do to you". Lilim may reject religion but they can't reject trivial demands of coexistence in society. "The result of the war was that the population separated, with the Vilifiers on the original world and the Nurturers on a new world" - the problem solved itself. [Answer] My own ideas to encourage lilim to reproduce and discourage women are a combination of education, economics and tradition. At the moment when a girl begins the transformation into a lilim, she is removed from the school that other children attend, and sent to a lilim-only school, where lilim are supported through the uncomfortable transformation, taught to fly, and educated to a higher standard than the teaching available at the school for woman-children and boys. The end result of this is that lilim are better qualified for further education, and have more and better employment prospects. With a higher income, lilim are more able to afford to have children. The next aspect is that women are traditionally wet-nurses and milk producers. This means that after a woman has given birth, she may find employment in feeding the offspring of lilim or producing milk for sale. The side-effect of this is that lactating women are much less likely to become pregnant. Lactation is a natural (and real-world) contraceptive. It's also a job that doesn't require much education. The third aspect is a product of the 1:1:1 gender balance between men, women and lilim. This gender balance means that men are outnumbered 2:1 by women and lilim. As a consequence, pair-bonding means that one third of the population will not be able to find a mate, and economics will cause men to tend to favor unions with richer lilim rather than poorer women. Additionally, lilim can engage in casual swoop-and-snatch sexual encounters with willing men, while women are both less able and biologically less willing (because women are more likely to become pregnant after any given sexual encounter) to do the same. Lilim are encouraged to resume their occupations soon after giving birth, especially those in higher-skilled and higher-paid jobs, meaning that a wet-nurse is a necessity for a career lilim who wants a family. So, the structure of Nurturer society favours lilim being mothers while those women who become pregnant look after both their own and lilim's babies, leaving lilim able to become pregnant again sooner, and women likely to lactate for many years, preventing their becoming pregnant again. [Answer] Some recessive genes (eg. blonde hair, blue eyes) correspond to features that people continue to have. A common theory is that if everyone in the village has brown hair except for one blonde then standing out from the crowd will help that person get the attention of a partner, so have more offspring. lilim (wings and talons) sound like they will stand out quite sharply! So if some % of men find the lilim more attractive than women, and if some other % of men are (for reasons of scarcity) drawn to whichever of the two is rarer then they will perhaps find it easier to find partners than women. [Answer] Mechanics of Reproduction Lilim can take either role in the reproductive process. They can be impregnated by a man or impregnate a woman. In either case the child has 1/3 chance of being male, female, or lilim. On the other hand if a man impregnates a woman the child is male 1/2 of the time and female 1/2 of the time. The Nurturers have designed their society so all reproduction is done through a Lilim. The inhabitants of the world believe this is the only way. Men and women cannot reproduce with each other. This legend has been perpetrated since the new world was settled. I leave it to your imagination how they prevent people finding out. Perhaps they have released a pathogen that makes all male-female pregnancies unviable, but which Lilim are immune to. [Answer] ## Nasal manipulation This is slightly handwavy,but might suit a near future tech / low magic setting. Every cleaning product (or maybe food) on the planet is loaded with enzymes that destroy female pheremones and/or cause males to dislike or ignore them. They aren't really conscious of it. Lilim pheremones, in contrast, smell amazing. This is insufficient in itself in a future tech setting but could couple nicely with some of the other answers. In any sort of magic setting, it's potentially a complete solution. [Answer] ## Generous Social security / pensions...for women Women have no fear of retirement; their pensions will keep them in comfort. Lilim, in contrast, must either breed or save huge amounts of money. Surprise: they have lots of little lilims running around! If you really wanted, you could have lilim getting family friendly tax breaks (especially income splitting, maternity leave, and child credits) in the name of fairness. [Answer] The numbers don't work. Assuming a stable population overall all childbirth must be from the lilim just to maintain a stable lilim population. Thus they're going to have to do something to alter the ratio of LX to XX children they bear. No incentives favoring lilim mothers over XX mothers can work. ]
[Question] [ Closed. This question is [off-topic](/help/closed-questions). It is not currently accepting answers. --- You are asking questions about a story set in a world instead of about building a world. For more information, see [Why is my question "Too Story Based" and how do I get it opened?](https://worldbuilding.meta.stackexchange.com/q/3300/49). Closed 1 year ago. This post was edited and submitted for review 1 year ago and failed to reopen the post: > > Original close reason(s) were not resolved > > > [Improve this question](/posts/228979/edit) I'm world-building a future where the USA devolves into a dictatorial state ruled by a single man. The following are true: * The dictator in question is a charismatic populist who is highly intelligent, wealthy, and well-connected. * The dictator takes power via a non-violent coup and is able to get the military to swear personal loyalty to him. * The dictator gains full control of the country through entirely legal means. At no point does he ever exploit legal-loopholes or gain support none-legitimately. With all that being said, what is the most probable way that the USA can devolve into a dictatorship through stirckly legal means? [Answer] In the USA, it is simple. Changing the US Constitution first requires a proposed amendment passed by 2/3 vote in each of the House of Representatives and the Senate. That proposed amendment must then by ratified by 3/4 of the States, within "a reasonable time". Although the current situation would not allow such a thing, obviously we HAVE amended the Constitution dozens of times, so it is not unimaginable that one party gains control of such majorities, under the sway of some politician (especially in times of war or great hardship), that then sways the House and Senate to amend the Constitution to make them President for Life, make them immune to prosecution, remove all legal impediments from the President, etc. Isn't that what Putin just did in Russia? The US Constitution can be amended. Every amendment can be repealed. Don't forget the entire Bill of Rights is amendments to the Constitution, your "First Amendment Rights", your "Second Amendment Rights", etc. Free speech, Freedom of Religion, the Right to bear arms, your right to a trial, your right to vote, all of it can be wiped from the board with 2/3 of each House and 3/4 of the States. Or modified, or suspended. No unanimous decisions necessary here, just these super-majorities, and we have done it before. Not to mention, even that mechanism is itself in the Constitution and subject to Amendment to make it easier! A temporary superiority of states, 38 at our current count, could permanently change the Constitution to require fewer states for future Amendments. Or to make it easier for the President to arbitrarily suspend the Rights of citizens. The changeability of the US Constitution is both a strength, for adapting to changing times, and a weakness, to be exploited by unscrupulous agents in times of crisis. [Answer] Her Majesty Elizabeth II, by the Grace of God, of the United Kingdom of Great Britain and Northern Ireland and of Her other Realms and Territories Queen, Head of the Commonwealth, Defender of the Faith. or Liz is Back and Angrier than Ever. [![enter image description here](https://i.stack.imgur.com/iV3Dp.png)](https://i.stack.imgur.com/iV3Dp.png) Your solution needs to be legal. However you don't say whose laws should be upheld. So I will do the obvious thing and answer in terms of the only laws that matter. I speak of course of the legal doctrine of the British commonwealth and the Divine Sovereignty of the Royal Crown of Saxe-Coburg and Gotha. Too long have the Western Colonies escaped our reach with their upstart "War of Independence". These so-called "United" States. They stole the word "united" from our most powerful and magnanimous kingdom which they seek to usurp. Give back our word! And their flag is just our flag with the shapes mixed up. Look! [![enter image description here](https://i.stack.imgur.com/SgkGW.png)](https://i.stack.imgur.com/SgkGW.png) That's not a new flag. That's our flag with the lines drawn differently. The colours are the same and all. After many centuries Queen Elizabeth is ready to take back her word and her country, by means of blood and carnage. She is indestructible when wearing her crown don't you know. This is all legitimate by British Canon law. Furthermore it is legitimate for the queen to reign as absolute monarch in America, whereas it would not be legitimate in England. In England they have changed their constitution to lower the Queen's power. However America never bothered making the necessary changes since they claim to have kicked her out altogether. [Answer] The same way other democracy's devolve into dictatorships usually Civil War. The Roman Republic is an excellent example of how this works. The Roman Republic was dead set on opposing monarchies and one person rule Even more financial than the US today. But going to a couple generations of nonstop Civil War change the perspective eventually, all the hardcore patriots who weren't killed in the Civil War We're so desperate For some solution that they would accept anything even Imperial rule. Proper packaging: Going back to the Roman Empire again it's a good thing to remember proper packaging whenever transitioning a democracy into a dictatorship it's important that you use the proper terms and formalities to make people feel more comfortable. Augustus is a good example of this, he avoided words like king or dictator instead call himself 1st citizen. Technically speaking he was elected to legitimate Republican offices and he kept the senate and elections happening. I expect that your dictator will call himself president, or perhaps 1st adviser to the president. There will still be a Congress and a Supreme Court but their role will be severely diminished. As for the role of president, if your dictator wants it for himself he might strengthen it bring it remove the term limit and just arrange for himself to be continually elected, if not he might instead have himself appointed to an advisory role to the president and then rob the president of any real power while all the office former powers are transferred to his adviser make a him a virtual puppet. To put it simply is it possible for a dictator to come to power in the US, sure. Anything is possible just need a right kind of factors, and the right kind of package. You'd have to make changes to the government of course, but governments change all the time our government a few decades ago is not the same as it was today. I'm choosing to ignore the word fascist and till you put a proper definition in your question. Fascist is a particular form of extreme nationalists, not all dictatorial governments are fascist. However until you say otherwise I'm gonna assume you just mean bad government as that is how the phrase is usually usually used nowadays unfortunately. [Answer] # State Of Emergency: Some kind of issue comes to a crisis point. The issue is irrelevant - inflation, energy, war, political gridlock, whatever - and a single election sweeps a slim majority into congress. * The rules of congress are changed to prevent filibusters and limit debate. * broad emergency powers are granted to the president. It won't matter if they're constitutional or not. * The supreme court is expanded to 36 members, placing presidential loyalists in control of the supreme court for life and completely diluting out the current members. Now anything is considered constitutional that the president wants. At this point, the president can do pretty much whatever he wants. There's no constitutional amendment, and it's all legal. As the dictator, I'd do the following: * The justice department investigates treason in the rival political party. Congress ejects rival members. Numerous rivals are declared traitors and permanently banned from public office (if not throw in prison). * Congress, now purged of the rival political party, defers decisions on most issues to the president and gives him discretion to extend emergency powers 'as needed.' Membership in the rival party is declared a felony (conspiracy to commit treason). * The 'conspiracy' extends to the media. Broad controls on the media are imposed to rid the system of traitors. We need to stop traitors from manipulating the public! Use China's media system as a model for how the censors run things. Now, to permanently enshrine the changes, you can amend the constitution. That will be harder, but with the supreme court supporting every decision against state legislatures, jerrymandering will allow minorities to take control in state governments. [Answer] Unfortunately, this is all too predicable, and quite possibly probably possible, too. Our dictator-to-be is aware that the easiest way to legally take control of the country is to win over the populace with lies and rhetoric. The populace are, unfortunately, both stupid and gullible (ref: all of history). Our dictator-to-be asks a rich, powerful friend of his to buy out a popular messaging service - it's hard work to start a competing messaging service from scratch, after all. This messaging service immediately removes all previous controls and bans, reinstating a certain, popular ex-President, and becomes a hotbed of unfiltered right-wing bile and hatred in less than six months. This ex-President rides the waves of his return to popularity, while decrying the constant legal pressure on him over tax investigations as more evidence of the left's attempt to silence the voice of the people. Two years later, Biden is removed from office after an underhand campaign of lies and President 45 becomes President 47. He swiftly changes the election laws 'to remove repeated attempts at fraud by the left', backed up by the current Supreme Court majority, cementing a Republican 'majority' for the next fifty years. Of course, after all this, there will still be a lot of anger and unease, and Trump will never be fully accepted by the establishment, and people need scapegoats to help them move on after periods of unrest, and after all, he's getting on a bit, and some say he may not be quite compos mentis, so the country will need a strong Vice President during all this time, ready to do His Duty when Trump is finally declared unfit to lead, now his usefulness has ended. Ladies and Gentlemen: The 48th and Final President of the United States of America: Mitch McConnell. [Answer] As far as I see it the main problem for this person is the 22nd Amendment which specifies that a US president cannot serve for more than two consecutive four year terms. As other have pointed out this can be repealed by 2/3 majority. I'm not an expert in the US constitution, someone please correct me if I'm wrong. After that, this person doesn't have to declare him (/her?) self a president for life or anything like that. Once they've amassed enough political power they can simply continue winning elections by rigging the vote to whatever they want it to be. This is exactly how many real world dictators operate today. If the OP considers it non-legitimate means, this person can win all their elections completely legitimately, due to their populist appeal and charisma and due to having reduced the main opposition party to being completely irrelevant and unable to compete seriously. ]
[Question] [ People of the forest, people who become trees when they die. The trees are interconnected, a giant web spanning almost the entire continent. The tree-web is a computer, it reads the impulses it receives from outside, like hormones released by people and animals, the currents and the winds, the vibration in the earth and many other things. The trees are able of transmiting information to newborns making them able to see various possible futures since the day their brain becomes capable of processing complex and abstract information. The trees also send memories of the past to the newborns. Children of this species know the consequences of their choices with a high degree of certainty, the same way a gambler can know the odds of a sloth machine, it is fixed, a known precise number. Example: A child of this species knows that if they pick choice A) instead of choice B) there's a 13.53% higher chance for their sister to die on the 27th of July of next year Example: Someone might also be able to see memories of the future if the conditions are predictable enough, thus being able to communicate in their minds with various versions of probable people who are yet to be born. Those people, if and when will be born, are going to have the memories of having spoken with the folk of the past. Example: A king might read a biography of his life that was written 50 years before his birth. Question: The Chinese language measures time from up to down and English folk measure time from left to right and almost all languages also measure time with ''before'' and ''after''. But the need is to know possible ways that people capable of seeing the future and being born with an innate sense of time would conceptualize time verbally, a sense that real-life humans do not possess, and real-life humans need to use specific grammatical concepts to make sense of time. So how is time verbalized by this species? Not looking for specific words or sounds but for CONCEPTS. For example, it doesn't matter that Romanians use ''Ciao'' to say goodbye and Italians use ''Ciao'' to say hello, It doesn't matter what the specific words are, it's about the concept of there being different words to say different greetings in various situations. ''greeting'' is an abstract concept which has meaning regardless of the words or sounds used. In the same sense. This post is looking for abstract concepts on how this species verbalizes ''time''. [Answer] Irrealis moods. <https://en.wikipedia.org/wiki/Irrealis_mood> The subjunctive, for any hypothetical future. The optative, for a world we hope could be. The potential, for the thing we think is likely. The dubitative, for the state of things we doubt is real. The hortative, when we are begging. The admirative, for when we are amazed at the state of things. The necessitative, for when it must be. If you are writing, the question is what sort of moods are available in the language you write in, and if you are borrowing moods from other languages, will your readers be able to follow you? [Answer] ### Some Basics Two concepts that immediately spring to mind, which you might want to look into further, are evidentials and also relative time vs absolute time. Evidentials are a piece of grammar that languages use to distinguish the reliability of some statement or concept. In English we (sometimes) use phrases like "I saw it with my own eyes" or "it's there in black and white" / "it's black letter law" vs "I'm of two minds on this" or "the jury's still out". These phrases indicate how relatively certain the speaker is of the veracity of the thing being talked about. People of the forest might have a broad (or long) deixis of such structures indicating how many percents certain they are through all the tangled branches of futurethought. For each either/or choice a person makes, the chances of his sister dying on any given day may change. Relative Time is simply a way of looking at all of time in relation to something else, usually the existence within time of the individual doing the considering. The "good old days" could mean the 1990s, the 1950s, the 1920s or even the 1430s all relative to who is actually considering what the good old days are. Assuming time in your world flows linearly, imagine you're on a boat floating down the river. Not only do things like trees and rocks and occasional bears pass by you, from future to past, but you and your boat are also moving through time, and being in the boat, you are also in a kind of narrative present where your experience is always "now" while other things either haven't passed by yet or else already have passed by. Absolute Time is simply a way of looking at all of time from an external perspective. Consider the same river, only now you're standing on a bridge looking down. You see the flow of the water, you see various boats and tangles of brush and occasional bears moving along its surface and within its currents. You are now experiencing time differently. You're still within time but you are also reviewing time as if it were external to your immediate perspective. This might be like reading one of those wall charts of history, or watching a movie. Each little segment or frame is a discrete moment in time that can be labelled with dates and places and other metadata, and when you blur them together it becomes a whole experience. [Answer] Just some thoughts at this point: * The future conditional is going to be far far more nuanced tense in this culture, rather than a simple if x then y there are going to be shades of meaning for probabilities and contingencies built into the lingual forms. * There will need to be terms for events that have yet to already happen, like those conversations that are certain to occur but have not yet taken place in the individuals living experience. * There will be a whole school of thought, and the concepts and terminology to go with it, concerning those who read their futures and try to turn aside from their expected fate. * Also there will be a whole industry around people trying to do better than they're expected to, a "self-help for the future impaired". * There will be a term for those who take extreme measures to ensure they succeed in turning aside a foreseen fate. Probably individual terms depending who they kill/try to kill in the process as well. * And a term for those who were expected to turn aside (or at least try to by whatever measure) but stayed the course because they were told what would happen one way and another. [Answer] The simplest answer is that their language would have several future tenses for different degrees of certainty. There is a similar case with past tenses in some real-life languages, like Turkish (though the certainty here is not about statistics, but about indirect speech). Say oldu means 'i am sure that happened', but olmuş means 'i am told it have happened/it have supposed to have happened'. So their language may have several future tenses, one for absolute certainty and several more for different degrees of likelihood. The absolute certainty one may even be the same at the present tense. [Answer] ## Temporally Ambiguous The biggest difference between your proposed language and anything that we have currently is that human language takes it for granted that time is experienced the same way by everyone. If I say "I will go to the store tomorrow" you can understand that as a statement of intent. However, in your proposed language that might not necessarily be true. "I will go to the store tomorrow" in that case could be a statement of fact, because the person speaking knows for a fact that they do go to the store tomorrow. Any time you see that kind of ambiguity, you can assme that your new tree person language has some grammatical structure to help clarify. ## Super Subjective I think the simplest change you could make to the tree-person langauge would be to treat the past and future on a per-subject basis, rather than assuming that it is consistent for all subjects. In other words, when you discuss things happening in time you cannot assume that your past, present, and future match up with anyone you are talking to. Instead you need to specify how an action related to you in time, but also how that action relates temporally to the person/people you are talking to. "I will go to the store tomorrow" only really makes sense if the person you are talking has the same tomorrow as you. If you are talking to someone in your past you would need to tweak the sentence to be clearer, and if you they are in your future you would have to tweak it a different way. At its simplest, the tree-preson language would need to account for the following: * Whether an action occurs in your past, present or future. * Whether an action occurs in another's past, present, or future. * How you related to the other temporally (your present is their past, their future is your past, etc.) The actual mechanics of constructing a language I will leave to others better suited, but I think the 3 points above cover enough ground that they are a good starting point. That should let two people talk to each other over any temporal distance and still be able to keep track of when things happen from a relative or absolute perspective. The truly complex part would come from adding extra layers and discussing events with different people. You can imagine the headache that would from having a conversation with someone from your future, and then discussing it with it someone from your past. Bonus points if you are discussing the conversation before you have it. But other than being more complicated, there really isn't anything in that scenario that isn't covered by the three general rules above and a species which grows up thinking that way would not have any more trouble communicating than we do with our limited temporal senses and language. [Answer] I think you are asking for proposed language of probabilities : if I chose option A, I know for certain there’s a 13.3% chance that X will happen ... We have a language for that, but it’s very saturated in the 90%+ region. When we say “safe”, if you take a look at an actuarial table, for most of your life this means you have a 99.9% chance of seeing next year. When we say “unsafe”, in terms of places where people die all the time due to poor health or misadventure, we’re talking about a 99.0% chance of making it to your next birthday, according to actuaries. And when we say “dangerous”, in terms of people climbing buildings without safety equipment (only about 6-in-10 of this group still alive in 10 years), we’re talking about a 95% chance of making it to the next year. And what we call “nearly suicidal” behavior; like traveling into the death zone of Mount Everest habitually (only 3-in-10 of year peers still alive in 10 years) is a 90% chance of making it to the next climbing season. Obviously, our language is biased by the cost of the unfortunate event which, in these instances, is total. Please allow me to propose a few other concepts for your language— 80% likely : “All but certain”. Definitely not a lifestyle choice. Only 1-in-10 people following this path as a lifestyle will still be alive for the high school reunion in 10 years. Probably not even a good idea in the short term, because of you choose this path even once-in-a-while, you are more likely than not to have experienced the “all but certain outcome” after 3 attempts. 50% likely : “meh” out of the range of lifestyle choices and into the range of you being able to depend on either outcome. If the motor doesn’t start on the first crank, try it again and it’ll work. The bad event is expected; and you’ll just keep trying until you get the outcome you want. 30% likely : “frustrating” getting the outcome you want usually takes more than one try. On average, you have to try twice to get one good outcome. And sometimes you have bad days and have to try much harder. 16% likely: “chore” you almost always get the unwanted result, and have to work hard (average of one positive outcome out of every four tries). 5% likely: “maddening” you may get the result you want one time out of every thirteen attempts. You are likely suspicious that the cause-and-effect relationship you have identified is mistaken, because the strength of the relationship between the two seems so weak. We’re back again in the range of lifestyle choices. You can follow this path as a way of life and only have a 4-in-10 chance of encountering the positive outcome in a decade of practice. 1% likely: “rare” you can try looking for this outcome once a week for more than a year before you expect to have seen it once (70 attempts before your compound chance > 50%). As a lifestyle, everyone following this path says they do get a positive outcome eventually, but it may take a whole lifetime of looking for it. As a social thing (like contest prize winners) it is possible you have never met a person who has gotten this outcome, but you may know someone who has met a winner. 0.1% likely: “rumor” you can choose this path your entire life and never see the hopes-for outcome. You will likely spend a lifetime looking for the good outcome here. As a social thing, it is possible that you have never met anyone who has even known anyone who got the positive result. [Answer] ## Relative vs Absolute Direction In most languages on earth, we have relative direction words: "Left" or "Right", "Ahead" or "Behind". It makes perfect sense to have such words, as we change our orientations all the time, and we experience things from our changing perspective. There is a terrestrial language, however, that lacks such words. They only have fixed, absolute directions, basically "north, south, east, west". This does grant them the seeming super power of always knowing where north is, but that's because they're always keeping track of it. ## Relative vs Absolute Tenses To us, time is absolute. We all experience it more or less the same (as relativistic effects are not a daily life experience for us). Our tense structures reflect this, so we have pretty absolute tenses, kinda like that one language who only has absolute directions. But to your people, time is relative. They are always changing which way they are "oriented" in probabilities of fate, depending on what they are looking at and what actions they are taking at the moment. It sounds really complicated to us, and so our first instinct is to give them a complicated tense structure to match it... but that's not how people usually operate. We like simple. To your future viewers, time isn't complicated-- they can see it all. It's right there for them to engage with and understand in a way that is hidden to us. I think they would have a simple tense structure that is relative to how they personally are experiencing time at the moment. You might have tenses for "more or less probable" than what they are currently "looking" at (like our "left" and "right"). You also might have a single tense for what refers to "past or future" from an absolute tense, but would more easily be used in situations where you have a prediction about the future made in the past, and then have another tense that is "retrograde" from that (like our "ahead" and "behind"). This solves all sorts of problems about making your tenses too complicated, at the cost that speakers of this language will have to be able to infer, through context, what orientation someone is speaking from. But we do that all the time with directionality, so I see no reason why it would be difficult for them to do so with time as well. Of course, this doesn't mean that they can't have words (or tenses) that are absolute (and super complicated). English has a word for North, after all. We just don't use it in every sentence that has spatial information in it, and neither would they. [Answer] ## Nothing Changes The human mind is already designed to make predictions about the future and draw on the experience of others for vicarious learning. Our Languages already address these facts; so, your forest people do not need to have a different sort of language to express themselves. ### Future Tense While humans are not perfect at predicting the future, we are pretty good at assuming how certain we are of a future event. Ask any 8 year old who knows what they want to be when they grow up and they can tell you exactly how likely they think thier dreams are. The only difference between humans and your People of the Forest is that humans only think they know how probable something is. But knowing the exact % chance of a probability does not change the range of certainties you may have about a thing. You could be certain, unsure, kinda-sure... it's all the same. Even today people say things like "I am 99% sure that..." when they feel a need to be precise. So, "I will probably get stung by a bee tomorrow." is the same sentence regardless of if you can make this prediction based on because the trees told you so or because you have it on your calendar to go work in the garden tomorrow. Your Forest People will certainly make better predictions, but the language used to describe those predictions do not need to change. ## Past Tense Our language is also perfectly suited to communicate about a past that we did not experience vs one that we did. "I crossed the street to get home yesterday" is functionally no different than saying that "Julius Caesar Crossed the Rubicon in 49BCE". We already makes statements about the past as facts without needing to address who witnessed that event. Furthermore, in humans, a memory of an event we experience is functionally no different that a memory of an event we've thought about. We only really know the difference between true memories and false ones because we can make guesses based on context, but humans are full of false memories that we speak about with certainty. So these memories of past lives will sometimes be talked about as though they were your own the same way we talk about false memories, but they will also be able to use context to separate the facts of thier own life vs facts about someone else's life the trees implanted in their memories. So while you may remember crossing the Rubicon in 49BCE, it is really no different than remembering a movie you watched about someone crossing the Rubicon. You will know that it was not actually you, because you know you were born WAY after 49BCE. ## Would the first-person plural become more complicated? Even though I do not share the memories of my ancestors, I still often say "we" when connecting my own identity with those from the past or future. "We won the war of Independence in 1783" is the sort of thing an American might say even though no living American fought in that war. Or in world building, I may say "we" when talking about humans 500 years from now, even though I certainly will not still be alive. Having genetic memories instead of just memetic memories would certainly change what groups a person may choose to identify with, but that does not automatically require a revision to the language structure. [Answer] # First, express your opinion about whether you are real. The tree-people are predicting the future actions of other people. Those other people are simulated in the tree-network and simulated-say things to each other about their predictions (from the tree network) of what will happen. Note that for the network to predict the future worth an oh-shucks, those simulated selves MUST pass the Turing test with flying colors. So when you say something, you have to decide if you think you are a real person seeing something "happen", or just a future simulated possibility seeing a simulation of something happen. Perhaps there is some premise or cue you can use to fuel your emotional certainty that you are non-virtual this time, even though your virtual self has been predicted to say that many times before. # Next, express your opinion about who your intended actions are contingent on. Someone else is going to act in a way that chooses one possible future. Those futures differ in what you are going to do, say, or want to accomplish. So you need to have a transdirect object in your language - contingent on who will you want to do something next week? # Throw in some game theory Your decision to have your daughter win a pony next year means some other guy is going to have to console his crying daughter who didn't win a pony. That means your statement that you "hope" she "will" win a pony should come with an implied threat, which your rival will hear when he envisions the results of his simulation of his daughter winning a pony, about what you are going to make happen to them if they try to contest your future. Threats are, as always, a convoluted language with many not particularly subtle yet legally effectual variations. # Now some SEO All the other people are running through possible futures. You need loud, musical, bombastic, alliterative, wonderful language prose that so stands out in their minds that, given a choice between 55.2% and 55.2%, they pick your 55.2% because they remember the future you were saying things in. (I'm going to save this draft before the StackExchange Creativity Basij bust up this party - I see three votes already, and answers like this are NOT HELPING!) ]
[Question] [ In this world, nations once came together and decided that global empires are generally a bad thing for the species as a whole - since their effect on history and culture is very similar to monopoly's effects on the economy. They also act like focuses of the attention, with everybody ambitious beginning to just want to either rebel against the empire or to overthrow the emperor and rule it themselves. So they came up with an international organization whose purpose is to keep the governments in check and prevent them from gaining a too large military or economical advantage over other countries, by force, if necessary. This organization is itself has a large military, manpower, and has a political influence on the countries, so they, theoretically, can take over the entire world with relative ease. But they stay true to their mission, only taking action to level out the playing field for everybody else (either by smacking those who got too greedy and imperialistic or by bootstrapping those who fell too far on the other side of the scale) and other than that let the governments of the world do whatever they want (both inside their countries, and to each other). Basically, they're a geopolitical antimonopoly committee with executive power and a dash of humanitarian aid mission. Now, the question is, what are the mechanisms that can prevent such an organization from becoming infiltrated or corrupted, and just deciding to conquer everybody themselves? At least on a timescale of one or two centuries, but preferably the more future-proofed they are, the better. It should preferably be some logical element of the organization itself and not something immutable that itself enforces its will on the organization - like an immortal CEO, or mind-affecting magic, or something like this. [Answer] With the structure you said, I'd say it's nearly impossible for that not to happen. I'd propose a bit of a frame challenge. Make them assassins "The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants. It is its natural manure." Thomas Jefferson. Think about it. A large planetary government is susceptible to corruption as any other government. In fact because of the larger scale they are likely to be even more corrupt. But a small highly organized group of assassins that owns nothing, rules nothing, controls nothing... etc. is the perfect weapon to stop empires. They are still human and can be corrupted, but the unique nature of the organization would hopefully prevent that. But having nothing to their name they are unlikely to grow fat and rich, unlikely to get bribes to pass laws since they can't... etc. that even if a member wanted to blackmail someone in exchange for turning a blind eye, that won't work since anyone in the organization can get that information. I'm gonna use corruption as an umbrella term for whatever you don't like. * They work in small cells. Few people per state/county. Each cell has a leader. * They lead normal lives. They don't stay in the office all day training how to throw shuriken stars. And they don't walk around with signature cloth denoting their status. They even recruit in secret. Think intelligence agencies. * They are not a complete secret. But they don't go around advertising themselves. They only justify their actions to the public in say a newspaper, website or in front of parliament. * They have access to all the governmental stuff. Databases, budgets... etc. * They are well trained and well prepared. Despite having normal lives each cell member has a sort of standard training and further specialization. * They only need to prove corruption to their cell leader, or panel of 3, in which case a sanctioned hit is ordered. Alternatively they have to send it to higher ups. * They use both their access and public information to gather information then analyze this to come to a verdict. * You can complicate it further by having them spy on the state in general. If they suspect a governor is plotting against them then why bother trying to use governmental databases? Just spy on the person in question. Then bring the allegations to the leader or panel. * The unique nature of the organization, the small size, the lack of a traditional leader, the compartmentalization... etc. means that it's very difficult to infiltrate or take down or even know about them. Each cell is separate, everything is handled internally. And they only face the public in say a website or in front of parliament. This reduces public exposure and even governmental exposure. * Being established before government means they can outlast it. For example if a president wanted to destroy them, what can he do? He is going to use the power of the state which in theory is greater. But by the time he orders the investigation of them they would already know. Even if a cell or two are compromised they will be eradicated and reestablished, now with a clear and obvious enemy. And because they only need to justify actions internally they don't have to worry about lengthy litigation or even escape. An expert assassin gets his hit sanctioned and takes the target out. * Murder is not the only answer, of course, depending on the severity of the crime. But I highly recommend them using murder from time to time so that people understand the full consequences of corruption. Heck, they can sometimes do it both ways. Build a case against some entity or person, then throw it to the courts. If the court fails the person is taken out. * There is always risk of failure but that's the burden that they take. If an assassin fails they might get killed or captured. Sure. But again it's an oath they take to keep order. I have no delusions that such a system is very radical and will have larger consequences or that it's perfect, few things are. But I feel that a small global group of assassins that is highly trained and possesses good resources is a good answer. Of course they do act as a boogeyman to states and politicians, holding the higher ups under a reign of terror and fear of assassination. I also think the implications and the brutality of it is quite nice. Ultimately someone will ask: Quis custodiet ipsos custodes? But that's my not problem. [Answer] One of the key elements of sovereignty is a monopoly on violence. If nations are allowed to retain their own militaries that could oppose the anti-empire organization (AEO), then by definition the AEO is not an empire. However, if the AEO has its own military too, then it is likely inevitable that it will ban nations having militaries because the only logical reason to have one anymore is resisting the AEO to become an empire. Such a ban would ironically make the AEO itself an empire. The only long-term solution is to prohibit the AEO from having its own military. It must instead ask the “good” nations to put down the “bad” nations. If the AEO oversteps, they simply refuse to participate. This is pretty much how the UN works, if you ignore the obvious flaw (added to appease Stalin) that allows Permanent Members of the Security Council to veto any actions against their own empire-building. And one of the UN’s first priorities was indeed dismantling the empires that directly led to WWI and WWII, aka “decolonization”. [Answer] Democracy The global empire preventers would work well as a democracy. It is not autonomous. It is landless and funded and staffed by all countries. If someone tried to use the global military to establish an empire favoring one nation, the other participating nations would prevent it. Another consequence of democracy is that the empire preventers (they need a new name) are bureaucratic and inefficient. It takes them a long time to do anything. That prevents things from happening fast. Good things happen slowly but more importantly bad things (like turning into an empire or dictatorship) also happen slowly and there is time to intervene once the direction of things is noted. Inertia can be a valuable quality in something that is very powerful. [Answer] First of all, if you are going to write something like this, you need to read the definitive master work on the subject, Asimov's original Foundation trilogy. Specific to your question is the third book in the series, titled The Second Foundation. Through out this series, the gross economic policy theory which is supported by the Foundations are a little different than what you are proposing, but the fundamental concept and underlying goal is the same; prosperity and survival for as many as possible. To answer your question, what you need is a second, clandestine and in some ways even more powerful organization which lacks the outward facing tools of power (military, economic strength, technological advantage) but possesses an inward facing power which can humble the first organization from within. This secret power doesn't even have to be real. It just has to be feared by the leaders of the first organization who know with absolute certainty that the sword of Damocles towers above their heads, ready to strike should they step out of line. The second organization should have methods for flexing its fictional muscles within view of the first organization. A infiltrated spy within the first foundation holding a humble office like filing clerk, who has the ability and responsibility to modify military reports, to add sightings of powerful but neutral military assets who waited at the edge of sensor range then left peacefully without incident. If those sightings come from a ship that subsequently didn't survive a later conflict, all the better. Just an unnoticed but ominous report, hidden in the official files, waiting to be discovered by a future first organization leader with imperial ambitions. [Answer] You are asking an impossibility. The problem is not organizational structure, but people. It is estimated that 1% of the human population are psychopaths who will seek out positions of power. Once they get that power, they will use it to remain in power and will destroy any organizational restraints that might exist. They will kill their rivals (Stalin), arrest others, and try to make a civil war (Jefferson Davis 1860). Look at what happened to the Roman church when the Pope had absolute power. Let me give some Lord Acton quotes: "Power tends to corrupt and absolute power corrupts absolutely. Great men are almost always bad men, even when they exercise influence and not authority; still more when you superadd the tendency of the certainty of corruption by authority." "Liberty consists in the division of power. Absolutism, in concentration of power." <https://www.acton.org/research/lord-acton-quote-archive> The only way to prevent one person from gaining that much power is to not have that much power in one position. This is the genius of the American Constitution: separation of powers. In other words, when a power hungry person has been elected president, he is constrained by the Supreme Court and Congress. Even so, we are constantly struggling with this and working to have new ways to balance power (such as on the internet). So, when you want to prevent empires, the only way is to have a number of smaller countries who when ganged together, can defeat the attempts at empire. Even that is doomed to failure because of the element of luck that will give a lot of wealth to one country for a while. Wealth and empire is always short term. (See Spain, England, Mongol, etc.) [Answer] Q: "what are the mechanisms that can prevent such an organization from becoming infiltrated or corrupted, and just deciding to conquer everybody themselves?" Let a Court decide about the interventions Suppose your anti-Empire organization was formed in a voluntary treaty, between countries, everyone has agreed upon things. You could form some independent body, like a Court of Intervention, to assert if certain measures comply with the treaty text. Let it be passive The organization only acts on request. It will research complaints by countries intimidated by big neighbours with imperial aspirations. Also, it should research complaints by peoples who are denied independent territory. Experts should assert the validity of these complaints. There should be some legal standing for actually requesting intervention, the organization itself cannot decide on intervention on its own. The army serves a treaty between partners, not the organization The large army should only be an instrument to enforce the treaty, it does not serve the organization itself. This army should be 99% deterrrence: The size of the army is to make sure that countries with war aspirations will stay reluctant to actually apply force. When allowed and agreed upon by the Court, defensive and preventive military action is taken, keeping the rogue country from e.g. moving troops outside its borders, or executing air raids. [Answer] > > This organization is itself has a large military, manpower, and has a political influence on the countries, so they, theoretically, can take over the entire world with relative ease. > > > Manpower, military force, and political capital don't just come from nowhere. I see two ways this organization can exist as described: 1. They have their own territory, with their own local population. In this case, they aren't actually "an international organization"; They're just another country. 2. They get their troops, funds, food, equipment, etc. from contributions pooled by the international community. In this case, they're going to have a hard time taking over the world if most countries decide to just stop funding and arming them. So really, it's hard to see how they could become an empire. [Answer] The "Protectors" are divided into orders and kept in secured towns across all of the individual nations. The order will need their host nations' permission to leave on a mission but can also refuse to go, so they are not a national military. The orders are divided into individual functions, such as doctors, teachers, cavalry, infantry, engineers. So no one order can have a large influence alone, and to mobilize effectively would take a long time. They do not keep their own supplies and are only given what is necessary for a mission by another organisation the "keepers". The Guards are very specialised, and rely on the Keepers. For example, cooks, supply chains, horse trainers. But the keepers get their supplies from volunteer nations. And last, all communication between all orders of Guards, Keepers or National leaders must be open to all parties, so there are no back channels. Under my barriers, to form an empire, the Guards would need to be let out of their secured locations. Arrange a way to supply their mission while they organise their forces. And either do that without any prior communication or with all of the nations knowing what is going to happen. I think the biggest risk would be while on a campaign to bring down a growing empire, to announce their plans and see who will join and hope it includes an alliance with a nation able to supply you. Doing their job is relatively simple, but to rebel would require many people to mutiny at once. [Answer] You should read the book ["Why Nations Fail"](https://rads.stackoverflow.com/amzn/click/com/0307719227) The word "empire" means many things. In this context, I think you mean "empire" as some kind of centralized, authoritarian tyranny. Right? On the other hand, some people would say that an empire is any nation that exploits other nations (e.g Victorian England or modern day USA). But I assume you do not mean that, right? According to WNF, the key to preventing authoritarian tyranny is to distribute the keys to power. A tyrant can only maintain control if she can bribe or otherwise motivate the keys. In a small African state the keys might be a couple of factory owners, the head of the military, and the media. One person can conceivably devise how to keep them all motivated. In the USA tyranny (so far) is averted because the keys are too many for one person to bribe. With AI however, this may soon change. [Answer] Perhaps unifying as a planet is necessary as an organization, and practically, given that efforts are concentrated on politics at a larger scale, between planets, and intergalactically. Thus, it is self-defeating to create a military to accommodate conflict between countries, or to even engage in this conflict in the first place. It makes the planet vulnerable to attack from other worlds. Rather, military efforts are focused on a larger scale, for governing between worlds, galaxies, etc. [Answer] As many other participants mentioned, your artificial universe is, say, 99,999999% improbable. The key question is, if there were such organisation, what would be THEIR reason to do all that "empire-leveling" stuff? Why would they not want to become ultimate empire themselves? If you propose an organisation of altruistic zealots, who's goal is peace and prosperity of humanity, even then the idea of leveling economic and military (which is a derivative of economic by the way) might of other countries seems absurd. First of all, monopolisation of world economy is not an evil mistake, it is a logical and historical consequence of humanity's productivity constantly rising, thus causing revolutionary change in society formation. You may want to read more in "The Capital" by K.Marx or "Imperialism as the Highest Stage of Capitalism" by V.Lenin So, according to all that the only plausible picture I can imagine is this one: USSR in alternative universe has not collapsed and took over the world. The whole world is socialistic, private property is prohibited and the power is in hands of World Soviet. but of course there might be (and will be) former capitalists and their supporters that dream of restoring the previous social formation. They will be rebelling and capturing some local regions all over the earth. The World Soviet will probably not choose to nuke them to ashes or eliminate completely with any other military tech, because Soviets are not mad, they don't need such bad PR. So they will try to control those multiple midget capitalistic countries, so that they don't cause much loss to themselves or anybody around. That could be a reasonable plot. ]
[Question] [ Would honey be feasible as a kind of money? It seems ideal to me and I'm wondering if I'm missing something. Honey is: * imperishable (like gold is) * hard to mass-produce or massively scale production of * infinitely divisible, by the milliliter or similar unit * intrinsically appealing. Gold is shiny; honey is sweet. These seem like good properties for a currency. Imperishability makes it a store of value. Divisibility makes it a unit of account. Maybe fungibility is a problem: some honeys are better than others. I know there are some synthetic honeys made without bees, and they could probably be scaled up, but let's just assume they're detected and dismissed as fake. [Answer] It can be compared to alcohol, another edible good that at times was used as currency Vodka was used as a currency in [Russia](https://www.atlasobscura.com/articles/vodka-currency-russia) when other currencies were not stable. In modern [Australia](https://www.vice.com/en/article/vvxp9m/thousands-of-australians-now-use-beer-as-currency) there are Facebook groups devoted to bartering in beer. According to [this site](https://www.alcoholproblemsandsolutions.org/alcohol-in-the-18th-century-european-expansion/), which references an NPR broadcast, "hard cider served as a currency in the North American colonies." Honey can last [just as long](http://factmyth.com/factoids/honey-lasts-forever/) as alcohol can. A modern gallon of honey has about a quarter the price of a gallon of vodka, which is not too far off. The main condition for alcohol - and therefore honey - to become widespread as a currency is when the usual currency is highly unstable and untrusted, or not available. It would actually be quite simple with only medieval tools to detect whether someone is diluting their honey with water, using a method similar to the [Scoville scale](https://en.wikipedia.org/wiki/Scoville_scale), relying on the human taste buds. You dissolve a bit of the honey to be tested in a lot of water (a standardized amount of water) and see if the sweet taste is still detectable. If it is still detectable, then the honey must have been sufficiently concentrated and not diluted. Or as a quick and dirty test, the person accepting the honey could just taste a tiny amount of it on their finger and decide based on that. (Not very sanitary, but they didn't care about such things in medieval times.) [Answer] > > imperishable > > > No. Frame challenge time. You may have been impressed by some stories of honey found in ancient Egyptian tombs and still being good. But that's because of a combination of factors. Even the tiniest amount of humidity will spoil honey over time. If it is to be used as currency, at the very least you have to check for its authenticity. Then you open that lid and some humidity from the atmosphere comes in... that jar won't last forever. --- On top of that, your mint is an apiary. There are so many logistical problems with that, your economist friends could have nightmares about them. Colony collapse disorder could lead your economy into catastrophic scenarios that would take decades to recover from. Anybody with a farm could also print their own money, which would be nigh impossible to distinguish from honey from the mint... This is another piece of economical nightmare fuel. [Answer] You've missed an important attribute - uselessness. It's not often discussed in economic explanations of currency, but it's important. One of gold's attractions is/was that, other than adornment, gold is pretty useless (at least, it was before electronic connectors became a thing). Immediately after WWII, cigarettes were often used as temporary currency. As you might expect, this didn't last, since the currency literally went up in smoke. Honey is mighty tasty, so its lack of utility is not what might be desired. Another issue is rarity. The basis for a currency needs a certain balance. It has to be rare enough to be "valuable", but not so rare that nobody can find any. Honey is, or can be, commonplace. Worse, it can reliably be farmed, sort of like Bitcoin today. [Answer] ### Before the invention of modern bee hives, harvesting honey killed the bees. So, before the modern box-shaped bee hive was invented, the only way to harvest honey was to smash open naturally-formed bee hives and take the honey that way. Naturally, this tended to kill the bees that lived in the hive, since they no longer had anywhere to live, reproduce, or protect themselves from predators. As a result, farming honey was much more difficult and expensive than it now is, which would make honey as a unit of currency much more difficult to produce. [Answer] ## Honey is not-uniform There are many varieties of honey. Honey is also blended for many different purposes. Honey can be (and frequently is) adulterated. Honey is very similar chemically to high-fructose corn syrup, which is often used as an adulterant. [Answer] Currency also needs to be easily transferable from person to person. You can't just pass someone one goldsworth of honey - either everyone has their own container and you move honey from your container to mine (but then how do we measure it and confirm it is the right amount) or we pass around little jars with premeasured amounts of honey - but those are breakable. And how are you sure that that isn't a jar with a false bottom or thicker walls that actually contains less honey than usual? ]
[Question] [ Could wings and feathers be capable of creating a sonic boom like whips do? The thunder bird of native American myths was a large raptor that was often accompanied by bad weather and the sound of booming thunder. If this was a real flesh and blood avian, perhaps it was so large it used storm winds to help it stay aloft, and the booming sound was the flap of it's wings. What size and length would wings need to be to produce this effect, and would there need to be any modification made to the wing tip feathers to endure the stress of a breaking the sound barrier. [Answer] I'd suggest a slightly different approach with the same effect. [Tom Holland's](https://en.wikipedia.org/wiki/Tom_Holland_(author)) scientific explanation of the origin of the myths surrounding the Thunderbird is that it arose with the discovery of a Pterosaur fossil. The ever popular [Quetzalcoatlus Northropi](https://en.wikipedia.org/wiki/Quetzalcoatlus) with it's 50 foot (15.5 meter - estimates vary about maximum span), its weight being as much as 250Kg (450 lb) would make it heavier than a couple of average humans by a fair bit. The sound of a [Golden Eagle](https://www.youtube.com/watch?v=fdUSqlidVaI) stooping, with its wings tucked in close to its body for streamlining - from over a mile-up, as it approaches the ground (some way from the camera and mike, sounds like a small fighter jet to me). The Q.Northroi could be lots louder. Then the "Womp" sound made by [its wings opening to decelerate](https://www.youtube.com/watch?v=Iku53cvInic). (soundtrack of a parachute opening). A big heavy bird like the Thunderbird of legend would likely reach a terminal velocity greater than that of a human by virtue of better aerodynamics - and more quickly, and a very impressive "Womp". Several of them playing in the clouds and making jet noises, simultaneous "Womps" then climbing to do it again out of sheer exuberance, might fit the bill. If I might say, adding L.Dutch's idea and mine - the crack of a whip in the mix might fill all the appropriate gaps in the needed soundtrack. Crack-crack-crack-CRACK-crack, Sheeeeeeuoch, WwWWwwoomP. [Answer] According to some paleontologists, Apatosaurus could produce a [sonic boom with its tail](https://www.livescience.com/52538-supersonic-sauropods.html) > > When an Apatosaurus dinosaur slapped its impressively long tail onto the ground, other beasts likely listened. Turns out, the long-necked dino may have broken the sound barrier with its tail whips more than 150 million years ago. > > > Paleontologists have all but gone back in time to prove the sonic booms, by creating and test-slapping a model tail made of aluminum, stainless steel, neoprene and Teflon. > > > The 12-foot-long (3.6 meters) model is just one-quarter the size of a sauropod tail, but it's still able to produce the distinctive crack that indicates it can break the sound barrier when whipped around, said Nathan Myhrvold, founder and CEO of Intellectual Ventures, a company that invests in technology patents and research. > > > From the above you see that the tail was long about 14 meters to produce a sonic boom at its tip. That's the ballpark figure you have to look at. Probably even longer, because wings are not whipped around like a tail. For reference, the wingspan of the WW2 Spitfire was about 13 meters, so you are talking about something covering at least two Spitfires with its open wings. [Answer] ## I don't think it works like that. Let's begin with what everybody knows, or should know, in order to approach the Bridge of Death, namely, that an Old World swallow [needs to beat its wings 43 times each second](http://www.armory.com/swallowscenes.html). Well, OK, to reach the other side you should know it is actually [about 7 times each second](https://streamofconsciousnessblog.weebly.com/blog/what-is-the-airspeed-velocity-of-an-unladen-swallow). I have this on the redoubtable authority of the Stream of Consciousness Blog, but they did give [a source](https://jeb.biologists.org/content/205/16/2461), leading to [Pennycuck, 1996](https://jeb.biologists.org/content/jexbio/199/7/1613.full.pdf), which says in no uncertain terms that the wing beat of ANY bird can be calculated according to the very simple formula, $f=m^{\frac{3}{8}}g^{\frac{1}{2}}b^{\frac{-23}{24}}S^{\frac{-1}{3}}\rho^{\frac{-3}{8}}$ Fortunately, they modified the original and took the moment of inertia out of that, which isn't known for most birds, or it would be much more complicated. Now what we can take from this is while we could alter the gravity or the air density, it wouldn't look good, and we could alter the wing length, but with virtually no effect (we multiply it by the frequency and get a 1/24th root of something), which means, either we can make the wing area smaller so it buzzes more like a hummingbird, or we make the bird heavier so that it must somehow learn to fly faster. This last seems in accordance with your preferences. Despite this, the frequency would reduce with mass unless the moment of inertia goes down, so the wings are going to have to be rather strange looking in order to improve the rate of flapping by a large factor. Because the effect of such a whip-cracking would be more like a motorcycle than a thunderstorm, I would humbly suggest that perhaps you give a little more credit to the legend. The bird simply has conductive barbules: [![enter image description here](https://i.stack.imgur.com/sxIfc.jpg)](https://i.stack.imgur.com/sxIfc.jpg) When it desires, it sends a small portion of each of its wings an endocrine signal that causes each feather to emit a hydrophobic compound in its oil, which detaches the barbules. Unlike the photo shown above, however, these barbules are designed to interlace at the start and end along each barb of each feather. A single feather unspools into dozens of meters of highly conductive thread, and the beat pattern of the wing twists this into a continuous fiber with other such threads. The result is comparable to [Georg Wilhelm Richmann's famous kite experiment](https://www.fi.edu/benjamin-franklin/kite-key-experiment), where he flew a kite in a thunderstorm and was killed by ball lightning jumping from the silken string, having less good fortune than Franklin. You may also compare the common [lightning rocket](https://en.wikipedia.org/wiki/Lightning_rocket) - though one of those is the size of a man, that is because it is trying to boost up into the storm from below rather than dropping its strand from above. Is the Thunderbird simply hungry for cooked meat, or is it a mysterious judge of character that makes decisions like a drone operator who might single out a disfavored foreign diplomat for a similar accident? I don't know - it would be best to go back to the native Americans and ask for more data. [Answer] Wings and feathers are not the only choice. A whip that can be "cracked" is 'easy enough' to fabricate and the motion required to get the tip to achieve supersonic velocity requires a far slower hand & arm velocity accompanied by an appropriate wrist action which accelerates the tip to 50 to 100 times the hand velocity. I at one stage owned a homemade whip about two meters long that could be "cracked" although not overly well (and often painfully by those with inadequate experience. :-):-(. A suitably designed or evolved bird could easily have an appendage that could achieve supersonic velocities if appropriately manipulated. Rate of cracking could be independent of flap rate. The biggest issue to overcome would probably be the provision of a sacrificial cracking-end as these experience extreme mechanical stress - many whips have a replaceable short leather end thong for this reason. This could perhaps be grown but an alternative would be the ability for the Thunder bird to add sacrificial material in some manne. ]
[Question] [ So I'm aware that the usual hard sci-fi array of spacecraft weapons generally includes self-guided missiles, rail guns, lasers, etc. However, in keeping with this spirit of hard science, I've encountered a truly terrible problem- lasers and particle beams are invisible in a vacuum: the lack of pretty colored energy beams tearing through spacecraft truly is a travesty. So, are there feasible weapons that could a) work effectively as a space weapon and b) produce a visual effect resembling a classic "energy beam" or "bolt"? [Answer] <https://en.m.wikipedia.org/wiki/MARAUDER> The MARAUDER project as part of the cold war Strategic defense initiative could potentially be what you are looking for. In short it's a railgun firing microscopic rings of bluish lightning that would most likely look like blue streaks when fired. It was a coaxial plasma railgun capable of launching tiny toroids of plasma at speeds of 3km/s to 10km/s, though I don't doubt with future tech we could bring it up to around 30km/s. These toroids are small, only around a couple miligrams of plasma, however you could also scale that up with a bigger cannon. These plasma projectiles on impact would hit the target with the equivalent impact of 5 pounds of tnt and around 10MJ or energy. It would also bathe the target in all kinds of electronics frying radiation. This damage in and of itself is underwhelming, however if it were utilized in a rapid fire fashion it could be devastating. However rapid fire increases heat buildup and wear on the weapon. The electronics frying capability would be devastating but only if the craft is not properly hardened against it. However, this could also provide justification for human crews as electronics would cease to function if not heavily shielded. But then again this radiation might also cook the crew inside as well so maybe not a great idea. In practical terms I am not entirely sure of its utility as a space weapon in comparison with other types. First of all, it has a relatively low velocity, far above most kinetic weapons, but also far below lasers and particle beams. This would make it harder to hit target beyond 1 light second accurately, but would also force the battles of your universe to take place at sub light second ranges. However it's low velocity could mean that it could have its toroids potentially destabilized by a particle beam or laser "shooting them down". Another issue that could further limit the range of this type of weapon is that the toroid would be unable to hold itself indefinitely and as it cools down it would dissipate into a high velocity puff of gas with negligible impact. This would have the advantage of making space battles in your universe relatively free of stray ordnance and other hazards posed by the deployment of kinetics. It also has the issue of having high power consumption which could be a detriment, but that's a universal issue with most energy weapons. That being said you'll need a nuclear reactor and a huge capacitor bank along with substantial numbers of radiators. This means that your universe would only see these mounted on relatively large purpose built warships. It also requires tanks of most likely cryogenic propellant to act as ammo, which could be a liability because puncturing them could leave you defenseless if the fuel leaked out. However this could have the added benefit of not requiring separate tanks for your plasma source as you could simply tap off some hydrogen from your main fuel supply. I am not entirely sure what its utility would be for orbital bombardment or defense but I'm guessing that it wouldn't have the mass or sheer oomph to penetrate the atmosphere. So my gut reaction would be to say it only works in space. However casaba howitzers which are also plasma weapons crossed with particle beams and the bastard stepchild of nuclear pulse units have been said to have some potential in that category so we can always be hopeful. Overall this weapon does have its advantages and disadvantages, it's a jack of all trades, master of none in regards to space weapons. It lacks the punch of kinetics or the speed of lasers or the simplicity of a missile rack, but it forms a nice middle ground. It is a markedly inferior weapon to the others mentioned so you'd need to come up with a rationale for choosing it over other options. Why would a government in their right mind pick this over a laser? Why would they use a railgun to shoot somewhat damaging balls of lightning when they could fire hypervelocity penetrators that can cleave through armor like a knife through butter? These are questions left for the author to answer. P.S. If you made it to the end of the article I have a crackpot idea about how to miniaturize this thing and get rid of the massive capacitor bank and nuclear reactor. You could used an explosively driven compressed flux ferromagnetic generator. In short it is a bomb that explodes around some electrical coils to create a pulse of power in a process that I can't entirely wrap my head around. This means you can use "shells" that you load into the railgun that detonate and power the machine for each shot. However even cooler is using metallic hydrogen superexplosives to do it. Assuming your society has the means to manufacture metallic hydrogen in bulk which means you probably have access to much better weaponry, but that's besides the point. These explosives work by forcing metastable metallic hydrogen to heat up to around 1000K to break it back into molecular hydrogen in a violent reaction that is over 50 times more effective than tnt for it's weight. The heating could be accomplished by a thermite derivative triggered by a primer cap of some sort. So this basically means that not only is the explosion so powerful you only need a small pellet to get the needed power, but not only that, you can use the superheated hydrogen plasma released as your propellant. Meaning in a single self-contained cartridge you can create ball lightning without needing all this fancy hardware. Just a barrel with some rails. However this has profound implications on you setting as this tech could allow for solid fuel rocket boosters that can achieve nuclear thermal performance levels, tactical thermonuclear weapons packaged into 60mm mortar shells (perfect for orion drives) and a whole host of applications that would promptly make this weapon vastly obsolete. Not to mention the fact that metallic hydrogen is potentially a room temp superconducting material meaning it could perform insane miracles. So with that I'll say good luck with this weapon idea. [Answer] Particles could emit blackbody radiation. When you accelerate your particles, they get hot as a side effect. You are ok with that. You accelerate them very fast and they get so hot that they shine with blackbody radiation according to their temperature. <https://en.wikipedia.org/wiki/Black-body_radiation#Spectrum> > > Black-body radiation has a characteristic, continuous frequency > spectrum that depends only on the body's temperature,[10] called the > Planck spectrum or Planck's law. > As the temperature increases past about 500 degrees Celsius, black > bodies start to emit significant amounts of visible light. Viewed in > the dark by the human eye, the first faint glow appears as a "ghostly" > grey (the visible light is actually red, but low intensity light > activates only the eye's grey-level sensors). With rising temperature, > the glow becomes visible even when there is some background > surrounding light: first as a dull red, then yellow, and eventually a > "dazzling bluish-white" as the temperature rises.[14][15] When the > body appears white, it is emitting a substantial fraction of its > energy as ultraviolet radiation. The Sun, with an effective > temperature of approximately 5800 K,[16] is an approximate black body > with an emission spectrum peaked in the central, yellow-green part of > the visible spectrum, but with significant power in the ultraviolet as > well. > > > Your particles shine and there are enough of them in your beam for this light to be seen. I could imagine that these particles will cool down as they radiate away their heat. The color of the beam will change with distance. The particles are moving with relativistic velocities and so to see the color change you will need a very long beam. [Answer] A. C. Clark's novel [Earthlight](https://en.wikipedia.org/wiki/Earthlight) comes immediately on mind. It describes a weapon which quite matches what are you looking for. Jet of molten metal propelled by electromagnetic field. But it could be worth of reading the book for battle description in original. The DARPA project [MAHEM is/was based on similar idea](https://web.archive.org/web/20120123174655/https://www.newscientist.com/blog/technology/2008/04/science-fiction-inspires-darpa-weapon.html), so it should not be completely unrealistic. [Answer] monitors add it The reason it shows up is simple. The monitors and cameras show them, as they can spot the laser frequencies. Visual confirmation of things becomes less and less viable on high speeds and distances. An ATC doesn't often look out of it's windows, nor do pilots. They mostly fly on instruments. In a spaceship this is even more so. Windows are a structural weak point and there is a small chance you would implement them in spaceships for anything other than recreation in the future. You'll have strong cameras with good resolution, zoom and frequency ranges for any visual confirmation you want to do, that the computer displays on the monitor for you. And for your purposes it'll display the lasers in all their beauty. If we go even more realistic we'll probably not fly the ship and fire the weapons as an advanced AI can only understand and react to such amounts of details in the correct way, but that isn't the best for some stories. [Answer] Casaba Howitzers Similar to some of the other answers here in terms of visibility mechanism, a casaba howitzer is an offshoot of the Orion nuclear pulse detonation engine technology. It is a nuclear shaped charge that converts a spherical blast into a roughly 2.5 degree beam with around 90% efficiency. This results in a stream of exceptionally hot plasma and dissociated subatomic particles streaking through space at a significant fraction of the speed of light. It would definitely be both visible from outside its path (due to blackbody radiation) and fast enough to be a practical weapon at space combat distances. It's also the way you make nukes practical in space since kiloton warheads will provide the same energy density as gigaton warheads, just in a much smaller area. (Which is perfect since most of the area of a spherical charge is wasted, whether in space or in atmosphere) It's not exactly a ship-mounted weapon since that 10% lossage does expand in a spherical pattern, so you've got to kick the device to a safe distance from your own ship before you set it off. But since most of that 10% will be headed away from you that's not necessarily very far depending on what you have for shielding/armor. [Answer] There is no stealth in space. Projectiles that are hotter than the background show up as hot spots, those that are cooler as cool spots, and there is next to no "cover" on scales much smaller than a globular cluster. So you don't care if your weapons emit. A problem with any kind of directed energy weapon is that inverse-square law. Their power goes down with the square of range. A problem with almost any kind of kinetic or mass-based weapon is that the enemy can see it coming and dodge, and they are slow. On top of that, you can random-walk, and at non-trivial distances make any kind of aiming a crap-shoot. A plus side is that most mass based weapons (except, say, black hole bullets) experience time, so they can have sensors themselves and redirect where they are going. --- So what you want is a fast weapon (reducing enemy counter-battery and dodge time) that can maneuver (hence mass-based). So one idea is a microscopic antimatter Bussard ramjet missile. It converts interstellar hydrogen into propulsion using magnetic fields and its own mass. It will glow ridiculously brightly as any interaction with the interstellar medium causes particle annihilation. As a staged missile, you start off with a conventional matter-antimatter converter launcher that gets the entire thing up to speed (perhaps powered by a laser up its backside). When it runs out of speed, it uses matter-antimatter converting technology to convert its payload missile into an antimatter one and lets it fly away from the "sabot" stage. Such a weapon can reach a good fraction of c, maneuver as it approaches its target, and if it appears to miss can self-destruct in order to bombard the target with high-energy antimatter dust. It will also be very bright. Maybe too bright, as it might be visible mainly in gamma rays. But the engine itself might glow in the visible spectrum. Another idea is black hole munitions. Micro black holes are another total conversion engine you could attach to a missile; they'll put out the energy of a nuclear bomb every second (the shorter their lifetime, the brighter). Throw some big science words at it; spin a micro black hole up to ring singularity speeds and charge it to permit coupling, and use it to accelerate propellant. Have three such black holes in a metastable orbit, and cause them to shatter as you approach your target, creating massive gravity waves and a directed neutrino pulse. Going further, your weapons are Alcubierre drives. They form an event horizon round themselves artificially, which in turn generates hawking radiation based on the steepness of the curve (which is bright). The munition literally breaks the speed of light and distorts space as it goes through a target, causing destruction. Of course, this technology also permits communicating with the past via bullets, so "shooting enemy ships" is sort of like using a nuclear bomb as a paperweight. You could have a gravity-munition that does space warping without the ability to break light speed, and has a similar near-singularity psuedo-Hawking radiation glow. Another exotic idea is controlled false vacuum collapse. The universe's laws of physics have done something similar to "phase changes" when matter goes from gas to liquid to solid in the past (during the period near the big bang). Some have posited that our current vacuum state is not actually the lowest energy state, but might be metastable; what we call the vacuum is actually a false vacuum. In that theory, the state of the vacuum can spontaneously collapse into a lower, more stable state (which would correspond to a change in the laws of physics, basically). Such a change could then propagate at the speed of light. Nobody would know it was coming, but it would literally rearrange the everything. What if there was a lower energy somehow unstable vacuum state that you could only arrange if you carefully encased it in exotic space-time geometry? Like, imagine a glider in the game of Life; it would propagate in one direction, leaving behind normal space, but messing up whatever it hit? The exotic space-time geometry that encases it might decay at a rate of a Planck distance every 10^10 Planck-distances traveled. In the game of Life, "spaceships" (self perpetuating constructs that move) travel at a fraction of the speed of light in Life (which is 1 square per iteration). Such a complex bit of space-time geometry might also travel at a fraction of the speed of light. Then, as it tears apart the laws of physics then they snap back, energy could be released, causing a bright glow. We could have it break conservation of energy (perhaps it ends up interacting with Dark Energy, changing the rate of expansion of the universe, in order to fuel itself), or it could just fuel itself using the interstellar medium. The interstellar medium is 1 proton/cubic centimeter. At the speed of light speeds, a 1 meter radius total conversion puts out 141 078 Watts. Based off the Stefan–Boltzmann law, the color temperature is 1251 K -- the color of glowing red iron. ]
[Question] [ Closed. This question is [off-topic](/help/closed-questions). It is not currently accepting answers. --- This question does not appear to be about worldbuilding, within the scope defined in the [help center](https://worldbuilding.stackexchange.com/help). Closed 4 years ago. [Improve this question](/posts/137395/edit) Is it possible to build a mirror cage in order to catch light in it? Let's assume the surface of the mirror reflects absolutely 100% of the light. Which shape of cage is the best to do this? Is it also possible to "fill" up the cage with light? [Answer] It may stretch the parameters of your question but I believe a combination of slowing the speed of light and capturing it in a lossless optical fibre system could do this. > > The speed of light is normally about 186,000 miles per second, or fast > enough to go around the world seven times in the wink of eye. > > > Scientists succeeded in slowing it down to 38 mph. > > > They did this by shooting a laser through extremely cold sodium atoms, > which worked like “optical molasses” to slow the light down. > > > <https://abcnews.go.com/Technology/story?id=99111&page=1> > > > --- > > By transforming the optical fiber span into an ultralong cavity laser, > we experimentally demonstrate quasilossless transmission over long (up > to 75 km) distances and virtually zero signal power variation over > shorter (up to 20 km) spans, opening the way for the practical > implementation of integrable nonlinear systems in optical fiber. > <https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.96.023902> > > > --- The device could consist of an incredibly long coil of optical fibre rolled into a ball and placed into your cage. Light would be fed into one end of the fibre-optic cable until it was 'full'. It would then emerge from the other end over a period of hours. If the light was to be kept for longer, the end of the cable could be connected back to the input. The light would go around the circuit until required. [Answer] 100% reflective mirrors do not exist in reality. The best we can get is dielectric mirrors, with reflectivity around 99.9% at specific wavelengths. That aside, if you want to trap light, just shape the mirror as a sphere with perfectly reflective surfaces. Any photon inside the sphere will keep bouncing in the sphere. A similar concept is employed in the making of the [integrating sphere](https://en.wikipedia.org/wiki/Integrating_sphere) (the only difference being that it is not perfectly reflective) > > An integrating sphere (also known as an Ulbricht sphere) is an optical component consisting of a hollow spherical cavity with its interior covered with a diffuse white reflective coating, with small holes for entrance and exit ports. Its relevant property is a uniform scattering or diffusing effect. Light rays incident on any point on the inner surface are, by multiple scattering reflections, distributed equally to all other points. The effects of the original direction of light are minimized. An integrating sphere may be thought of as a diffuser which preserves power but destroys spatial information. It is typically used with some light source and a detector for optical power measurement. A similar device is the focusing or Coblentz sphere, which differs in that it has a mirror-like (specular) inner surface rather than a diffuse inner surface. > > > I have not been able to find any reference to the cited Coblentz sphere, though. [Answer] Not with conventional mirrors: Even with something like 99.9999999...% reflection, there are losses. The light is reflected back-and-forth a trillion times inside a box, which causes the seemingly insignificant loss to accumulate fast enough and the light fades almost instantly, in human perception. Edit: Based on SpoonMeiser's comment, the optic fiber has a bulge somewhere along the fiber. The light is trapped and spirals back-and-forth along the bulge. The length of the bulge determines the frequency of the light it can trap. The article has no mention how light is caught and then released on command. A [resonance bottle](https://phys.org/news/2009-07-physicists-multifunctional-storage-device.html) is a very small molecular structure [Answer] No, because light moves at the speed of light. That means it can cover the circumference of Eart multiple times in a second. You will let all the light out before you can close the lid. Also each photon will impart momentum to the walls upon hitting them, even if they are magically 100% reflective. Over finite time they will lose energy and become non-visible radiation. You can get more kick for your money by buying a battery and a flashlight. [Answer] # Q1: Is it possible to build a mirror cage in order to catch light in it? Yes in fact there is an existing term for this in physics and engineering: The Optical Cavity <https://en.wikipedia.org/wiki/Optical_cavity> > > An optical cavity, resonating cavity or optical resonator is an arrangement of mirrors that forms a standing wave cavity resonator for light waves. Optical cavities are a major component of lasers, surrounding the gain medium and providing feedback of the laser light. hey are also used in optical parametric oscillators and some interferometers. Light confined in the cavity reflects multiple times producing standing waves for certain resonance frequencies. > > > (emphasis mine) ## Non-physicist explanation Optical cavities are literally a pair of mirrors or other material that reflects light. They are configured so that a light wave reflecting on either mirror will keep the same frequency and overlap strongly with the other light waves in the cavity. When this happens the totality of light waves in the cavity will 'constructively interfere' and add up thereby forming a single more powerful light wave of the same frequency. As you pump more light waves into the cavity, by keeping the same frequency on each reflection, you may continue to add up more light waves thereby forming an extremely energetic light wave. This behavior is called resonance. Consequently, when you remove one of the mirrors after doing this for some time, the cavity will emit the powerful resonant light wave. The light wave emitted will carry the total energy of all light put into the cavity but as a single wave (boom laser). Errata: \* Photons and Light Waves are the same thing (per wave-particle duality). I call them light waves here to drive home the wave mechanics that make this work. \* When the constructive interference occurs, the two waves are essentially adding together. Since mirrors are not perfect, or their placement might not per perfect, said interference will not be perfect either. Consequently that means the waveform after interference will carry sub frequencies or nodal pairs. This will change the overall resonance behavior or may cause issues with the cavity as a whole (heating it up or light escaping) \* Resonance is occurring because multiple waves will constructively interfere over time forming a more powerful photon or set of photons. Since interference is not perfect, ultimately you can get close to resonance but not perfect. Ideally the cavity should be adjusted or automatically adjusted to keep as close to resonance as powerful and to emit the wave before the cavity fails or becomes permanently damaged. # Q2 Which shape of cage is the best to do this? According to the [stability diagram for a two mirror cavity](https://en.wikipedia.org/wiki/File:Laser_resonator_stability.svg), the most stable configurations are plane-parallel and concentric (upper right and bottom left of the linked diagram). # Q3 Is it also possible to "fill" up the cage with light? Yes. See above. [Answer] Without assuming an extremely (and unreasonably) fast means of replacing the entry aperture with a (perfect) mirror, or and extremely (and unreasonably) large cage, even if you grant perfect mirrors it won't work. Regardless of mirror geometry, the fact that any beam of light will spread ensures that eventually all of the light will bouncing around with essentially uniform dispersion, and some of that will hit the entry aperture and exit the cage. This process will automatically self-regulate, so that the power exiting the aperture will equal the input power. For "reasonable" cage sizes, as you close the aperture the input power must drop to zero, so the exit power must drop to zero as well, and the energy content of the cage must drop to zero. The obvious way around this is to make the cage very big. Then the speed of light will allow you to close the aperture fast enough to allow some light to remain within the cage. [Answer] If you have a mirror that can reflect 100% of the photons that land on it, it doesn't matter what shape you use. As long as the container the light is placed into is perfectly sealed and the inside is a vacuum, you will be able to store it in the cage forever. Why? because your material is 100% (not 99.9999%, 100%) reflective, it will absorb no energy and shoot out as many photos as it receives with the same velocity. Light is never absorbed so just keeps bouncing around. The shape only matters if you want to store more energy, because you will need to increase the length the light bounces before it exits the box. I would recommend a very long and straight box, shoot the light in almost parallel (the closer to parallel the better) to the entrance and let it bounce all the way down and out. Seal the Box and you have the light trapped inside. Now you need a vacuum. If there is anything else inside except a vacuum you will lose energy. Why? because your photos are going to hit the molecules inside the box and be absorbed by it in the form of heat energy. So even if the outside is perfectly insulated and reflects 100% of the energy, eventually all your photos will have hit that one special molecule that is still inside the box and you will just have one super fast molecule bouncing around inside. Finally you can't exactly fill up a shape with light. Light has no mass and doesn't take up space. It can interfere with itself, but thats about it. [Answer] If you don't need mirrors you could convert (compress?) light into matter for easier storage and then back again when needed. ]
[Question] [ # Problem statement I am building a world where the flora and fauna is based on that of [Gondwana](https://en.wikipedia.org/wiki/Gondwana), the lost supercontinent that consisted of South America, Africa, Madagascar, India, Australia and Antarctica. One of the key biomes of this continent, linking all the other regions together, is a vast savanna stretching across the continent in the tropical and sub-tropical regions. The wildlife of this continent is based on those creatures that evolved after the fall of the dinosaurs, but only on the southern continents. Many of the most common land mammals that we know of today evolved in the north ([Laurasia](https://en.wikipedia.org/wiki/Laurasia), at the time) so the only mammals on the continent are [prototheres](https://en.wikipedia.org/wiki/Prototheria) (egg-layers), [marsupials](https://en.wikipedia.org/wiki/Marsupial) (opposum and kangaroo and more), [xenarths](https://en.wikipedia.org/wiki/Xenarthra) (sloths and anteaters), and [afrotheres](https://en.wikipedia.org/wiki/Afrotheria) (elephants, elephant shrews, hyrax, and aardvark). If you look at those animals, you will see preponderance of insect eaters, such as aardvark, armadillo, anteaters, echidna and more. So, this sort of mammal ecosystem is best justified by a dominance of termites as the primary herbivores. [![enter image description here](https://i.stack.imgur.com/1cT9g.jpg)](https://i.stack.imgur.com/1cT9g.jpg) # Question What changes, if any, do I need to make to a world to justify termites being the primary herbivores on a semi-open savanna? ### Considerations * The competition from termites must be such that grazing herbivores never evolve. In turn, mammalian carnivores that specialize in grazing herbivores (wolves, lions, etc) never evolve. There are a couple of shrub browsers (kangaroo) and a few tree-destroyers (elephant and giant sloth), but nothing like wildebeest, horses, or buffalo. * Large predators in this world are either [birds](https://en.wikipedia.org/wiki/Phorusrhacidae) or reptiles ([giant monitors](https://en.wikipedia.org/wiki/Megalania) or [land crocodiles](https://en.wikipedia.org/wiki/Quinkana)). * The savanna biome is immense, covering nearly half the continent, an area larger than Africa. There is a mix of grassland, open forest, and closed thorn thicket. The termites must be dominant in all parts of the savanna. * If climate affects competition between termites and herbivores, it can be adjusted to favor the termites, so long as the mix of tree and shrub types is possible. [Answer] Make grass a bad source of nutrients. It's not the competition from termites that causes grazing herbivores to never evolve, it's their lack of a suited food source. Grazing animals rely on grass as a fast regrowing source of nutrients. In turn, they drop their manure on the plains, fertilizing the soil for the next generation of grass. If this cycle is broken (or doesn't exist to begin with), there's much less fresh grass than one would expect and bush fires may regularily destroy what's left. Grass blades have sharp edges, occasionally causing little cuts if you draw them through your fingers. The sharpness is caused by little crystals lined up on the very edge of the leaf / blade. In addition, the flat of a grass blade is covered with little hairs that act like barbs. You can draw a blade through your fungers in one direction, but not in the other. If you eat grass, you have to cope with these defence mechanisms. These could have caused herbivores to specialize on "less defended" food like bushes or roots, where thorns can be evaded. Another consideration is the water source of plants. Grass cannot reach its roots as deep as bushes or trees, so it depends on regular rain. On a continent like Pangea without major moutains or diversity in biomes, how often does it rain? There might be one rather short rain season a year (if at all) like in the african savanna. Gigantic herds of grazing herbivores have to literally cross the african continent twice a year to find sufficient fresh grass to survive. Pangea might be too big for such migrations, killing grazing species on the continent alltogether. --- Termites, on the other hand, are detritivores, consuming dead plants at any level of decomposition ([according to Wikipedia](https://en.wikipedia.org/wiki/Termite#Diet)). Different species have specialized on different plant matter, including wood, faeces, humus, grass, leaves and roots. Some even practice fungiculture (they grow their own fungus). Wikipedia further states: "It is assumed that more than 90 percent of dry wood in the semiarid savannah ecosystems of Africa and Asia are reprocessed by these termites." [Answer] If you massively increased the use that grass makes of silica, to the point where grass leaves are made primarily of silica rather than cellulose, the leaves become inedible leaving too little nutritional value per unit area to support large herbivores. Termites, ants, and other insect herbivores can continue to harvest the stems and roots of these glass-leaf grasses as cellulose feedstock for their fungal gardens but mammals can't get a good meal. [Answer] There are only trees. [![baobabs](https://i.stack.imgur.com/AGPnK.jpg)](https://i.stack.imgur.com/AGPnK.jpg) [source](https://cosmosmagazine.com/climate/africa-s-ancient-baobabs-are-dying) Grazers need grass. Browsers need browse. In this world it is too dry for that. There are only trees - big ones that can reach the water deep underground. Wood is the only readily available vegetable matter. Termites are the only animals that can subsist on wood. [Answer] ## Win the multi-million year-long war against the Ants. The dominant animal species, by weight, in almost every ecosystem on Earth are ants, which are the main predators of termites. Given that scientists estimate that there are 1000 pounds of termites for every one living person on Earth, I'm going to assume that they are the dominant herbivore in any place where ants account for the majority of the terrestrial bio mass (nominally, 15-20%; in the tropics: 25% or more). Ants and termites have been at war for millions of years. Ants communicate by the use of pheromones, so if you trick their soldiers into thinking it's their job to protect you, by say: smelling like ant eggs, not only have you essentially defeated your greatest advisory, but depending on the type of ant and the level of their now symbiotic parasitic relationship, e.g., leaf cutters, you also have slaves bringing you food if you can convince them to live at your house. [Answer] Perhaps a disease would be a good way of doing this. If you only had a couple of grazing mammal species to begin with, they could infect each other, or through the water. Some bison equivalent to black plague or ebola, that would drive the population down to below the threshold for genetic variety. I think that species appear very gradually, and disappear suddenly. Species appear from similar previous species. In this case, nothing similar is left, and the termites have taken over the ecological niche of eating plant and being food for predators. It's similar to the way Madagascar has lemurs in the niche that monkeys fill elsewhere. Monkeys never reappeared there. [Answer] Make your grass analogs toxic to mammals but not to insect life; termites in particular use [Naphthalene](https://en.wikipedia.org/wiki/Naphthalene) as a repellent to protect their nests from predation. If the grasses themselves were high in a toxin that the insects harvesting them were immune to, or better yet had a use for, then they, and possibly a few specialised grazers, could exploit the grasslands. Doubly so if they preprocessed the material, stripping the toxins out for defensive use and feeding the purified cellulose to fungi as a food source. Leaf cutter ants and a number of termite species use a "fungus garden" to process leaf cellulose while other termites carry gut bacteria that do the same job. Mammals trying to eat those same high naphthalene grasses would be poisoning themselves with every mouthful. [Answer] Make your termites omnivorous and predatory when meat is available. Hunting and killing any animals that enter their territory (Which spreads for miles) Under normal circumstances, the termites would mostly be herbivorous workers, but when they feel threatened the colony produces carnivorous soldier termites that swarm and consume any animals they find. The only animals that could survive a million-strong swarm of hungry insects would be ones that the termites find unsavory. Perhaps they exude some pheromones that calm or stun the termites around them. Like a beekeeper dosing their bees with smoke. In general, ants and similar pheremone-based colonies of insects operate on a reactionary basis. If you kill an ant, the ants around it can smell the alarm-pheremones it released. This goads the soldier ants into attacking anything non-ant in the area of those pheremones, and tells all the other ants to lay a "enemy is back that way" trail as they leave it. A big animal like a rhino or elephant couldn't help but accidentally step on your termites and draw the wrath of the nest. The only safe places would be in and around rivers where things are too wet for the insects to swarm in any significant quantity. [Answer] Microbial Evolution The gut fauna allowing for cellulose digestion in a Ruminant gut never developed. The only microorganism that can digest the cellulose are the flagellates that live in the termite gut. This way they are the only species that can get any gain from cellulose. [Answer] ## Fire The Savanna is subject to frequent fires, the trees are sturdy enough to survive, but the grasses take a few months to a year to regrow. Termite mounds are relatively immune to the fires, but grazing animals can't survive the frequent lack of fodder. ]
[Question] [ ### Description So fellas have you ever head of pig from hell, well if you haven't its called the [Entelodont](https://en.wikipedia.org/wiki/Entelodont) and it is an extinct pig like omnivorous mammal that resembles a giant boar. It is thought to be most closely related to hippos and is about 6ft tall. [![Entelodont](https://i.stack.imgur.com/rOrqD.jpg)](https://i.stack.imgur.com/rOrqD.jpg) ### Question Basically what I want to know is if a group of people could domesticate these animals, and use them for riding into war and for hunting. I'm thinking they would be like a mix between horses and dog (in physiology not psychology) as they they posture that would allow for riding like horses, but also have canine teeth and are omnivores like dogs. And as for them being like related to hippos well [click here](https://www.youtube.com/watch?v=mjdr-FwG71s). So could these creatures be domesticated or at least tamed? [Answer] Every animal humans want to domesticate must conform to a series of criteria. This is why we didn't domesticate rhinos instead of cattle, or lions instead of dogs. To be domesticated, an animal must: * Have a varied diet and thus be willing to eat humans' scraps * Grow fast - the longer an animal takes to mature, the longer it takes to make it valuable * Be willing to breed in enclosed spaces in captivity * Be "pleasant". Yes, some domesticated animals like bison are aggressive, but we have to keep them in massive enclosures. * Be calm and "brave". An animal that runs away every time you step towards it cannot be domesticated. * They must have a flexible social hierarchy So, to determine whether Entelodonts are a viable candidate for domestication, we must see if they comply with these points. Obviously, we don't know some things about them, so we should leave room for educated speculation. For the first point, entelodonts are fine, since they are omnivores. Omnivores also tend to be opportunistic, so would eat food given to them by humans if they thought they were safe. I've done some light research on all known Enteledont genera, but could not find out when they reached maturity. In this case, I will have to look to their modern relatives. Pigs reach maturity at 6 months, but growth rate will be different for carnivorous animals. The entelodont Archaeotherium was a predator that is thought to have cached kills, indicating a similar niche to the leopard. Carnivorous animals are usually more intelligent and "skilled" and therefor take more resources and time to raise. The leopard's maturity rate is considerably higher than the pig's, at 2 years. I think that's an alright amount of time, and anyway it will decrease after selective breeding. Both hogs and modern terrestrial apex predators seem to be okay with breeding in captivity, so I will assume there's a yes to the third one as well. This is where it gets tricky. I'm not sure if an entelodont would "be pleasant" with humans. But, if humans can domesticate wolves and half-domesticate bison, I wouldn't put it that far past them to do it to entelodonts. There is little documentation I could find on entelodont behaviour, but I'm gonna go out on a limb here and say that "They probably weren't skittish". Far larger than humans, with bigger teeth, I somehow doubt they would have much fear of us once they became accustomed to our presence. I think that the last criterion is good with entelodonts too. All evidence indicates that they weren't highly social, such as scavenging, caching prey, omnivory etc. Therefore, I think that entelodonts could potentially be domesticated. Domestication is a bit of a gamble, and it is never a guarantee that it will turn out right. But if we did domesticate entelodonts, what would happen? The general rule is that domestication makes the species smaller and dumber. They don't need to find food, survive predators and other dangers, or really do anything except eat, sleep and breed. All that doesn't require much processing power to do, and bigger brains cost calories, too. If you are domesticating the entelodonts for transportation, they will grow stronger. If you domesticate them for war, they will become more aggressive and less responsive to things that would normally distress them, like the death and loud noises of a battlefield. If you want them for aesthetic purposes, they will become more extravagant, or their hair will change colour, or their tusks will grow longer or whatever you want. So, to summarise: *Entelodonts could* be domesticated, and they would change overtime depending on what you're breeding them for [Answer] There is no way to answer this. Domesticability is primarily based on criteria that do not leave fossil evidence. The animal needs to engage in hierarchical social behavior (or be semi-social and group tolerant like cats) , they need a calm demeanor (at least once raised around humans), and they need breed easily. All three of these are unknowns for entelodonts. You can't even make an educated guess based on relatives, horses and zebra are extremely closely related and yet one was easily domesticated and the other has not been to this day. If you want to have domesticated entelodonts, have them, and no one can say its impossible. [Answer] Domestication doesn't follow the cuteness of the babies. Domestication requires that the animal have herd instinct, rather fast reproduction rates and a docile attitude. [Boars](https://en.wikipedia.org/wiki/Wild_boar) and [hippos](https://en.wikipedia.org/wiki/Hippopotamus) are well known for their bad temperament: > > Boar attacks on humans have been documented since the Stone Age, with one of the oldest depictions being a cave painting in Bhimbetaka, India. The Romans and Ancient Greeks wrote of these attacks (Odysseus was wounded by a boar, and Adonis was killed by one). [...] Actual attacks on humans are rare, but can be serious, resulting in multiple penetrating injuries to the lower part of the body. They generally occur during the boars' rutting season from November to January, in agricultural areas bordering forests or on paths leading through forests. > > > and > > The hippopotamus is among the most dangerous animals in the world as > it is highly aggressive and unpredictable. [...] The hippopotamus is considered to be very aggressive and has frequently been reported as charging and attacking boats. Small boats can be capsized by hippos and passengers can be injured or killed by the animals or drown. > > > Since we don't know about the Entelodont attitude, we can only guess based on its descendants. I would say domestication would be difficult (mostly due to reproduction rate and aggressive attitude, as I assume they did have offspring rather slowly), but taming should be feasible. [Answer] Yes. Any animal can be domesticated. Domestication is simply breeding the traits you desire such as docility, size, obedience or even the colour. The Russians did a study on foxes and domestication See [Man's New Best Friend](https://blogs.scientificamerican.com/guest-blog/mans-new-best-friend-a-forgotten-russian-experiment-in-fox-domestication/) All it takes is time and patients... [Answer] Short answer - Domesticated, yes. Tamed, possibly. Let's demonstrate with a few examples. Humans managed to domesticate dogs, which were initially, pre-domestication, wild and I'm assuming, feral. Same with horses, boars, cats - you get the idea. But domestication comprises of breeding in selective traits like docility and obedience and breeding out violent behaviour and brutality. Pack nature also comes into play - when you own a dogs, they obey you only after they accept - to some extent - that you are the pack alpha. But if you are raising an animal for war, then the animal necessarily must have an aggressive nature. So what you want is an animal which has obedience bred into it, and a pack nature, and which accepts its owner as the alpha. But it also needs to hold onto some of its violent nature. Aggressive, not feral. So if you are going for a long-term process, you may be able to domesticate the entelodont. Taming essentially involves cowing an animal into submission. Taming is a shorter process than domestication - it can be done within a single generation, while domestication stretches over multiple. Now tame might not be enough to ride into war - the kind of aggression required in a war beast may just as easily turn on the rider. It may work, though, if the animal is not particularly intelligent. I don't know about entelodont, but I do know that wild boars are one of the most intelligent species in the animal kingdom. [Answer] ## Any mammal can be domesticated. The key is to obtain new born young, raise them around humans and familiarize them with human interaction by weaning them and feeding them, even if as they mature not all their food is obtained directly from humans. Once you've started this process you simply weed out the more aggressive or overly fearful juveniles and bred from the more passive and less aggressive survivors. For example foxes are wild animals yet modern experiments have shown they can be fully domesticated within a few generations by applying these simple rules. The key problem with this process however is size. The larger an animal is the longer each generation lives and the longer it takes to domesticate them. So there has to be a really strong incentive to domesticate large animals. Historically in most cases this was for use as food (e.g. pigs/sheep etc) or alternately as beasts of burden (e.g. horses). So if we're a talking a proto-historical setting like for instance a similar period in history to when horses were domesticated it could take a couple of centuries or more to achieve full domestication. Presumably at first as food but then later as the captive population became both abundant and tame as transport (or both). This is because once you've domesticated a species you can start selectively breeding it for the purpose you want. As meat animals? You might breed it to be smaller in stature with a larger bulk e.g. similar to domesticated pigs. As pack or riding animals? You breed for larger size and greater endurance. Both are possible but will take additional time, perhaps centuries after the animal is first domesticated because you are now not just breeding for passivity but also for some very specific genetic traits that will take time to achieve. The only exception?** Your try to domesticate Entelodonts in the 20th or 21st century and you have current or almost current scientific knowledge to accelerate the process as per foxes. [Answer] Okay, i know i'm answering kinda late, but just looking at the back of that animal i can instantly see it won't be able to be ridden on. No animal with such a hunchback would have the strength to carry a human. If you want to use that animal for transport it first needs to be bred into a more stable condition with a flatter back. Edit: Okay i know i didn't really answer the actual question OP asked, which for some very stupid i didn't think about, but when it comes to the question i don't see any reason why it couldn't be domesticated except maybe size. From the picture OP showed it looks enormous and one of the main factors in domestication is being able to consistently feed the animal, like one of the main reasons we don't have pet bears or tigers (excluding the fact about them being highly dangerous and not being pack animals) is that they need high amounts of food. Of course since it's your story so you could go the simple route and say that your society has an abundant of food, but if you want it a little bit more realistic you may have to shrink the animal a bit. I honestly don't know about their temperament, but i'll just assume it similar to boars, which were hard to domesticate, but we clearly have pigs so it obviously worked. Another factor is how quickly they mature which i yet again don't know so i'll just use boars as a template and since we have pigs today i'll just say that ones also checked. Basically everything except the feeding of the animal seems reasonable to me. Hoped this answer was at least a little bit better than the previous i gave ]
[Question] [ Following on from [this question](https://worldbuilding.stackexchange.com/questions/12705/steam-boats-of-ancient-rome) which specifically asks about the consequences of aeolipile development, how can my ancient Roman civilization develop effective steam power for use in their ships? I assume this is just about impossible in our word, but what changes might make this possible? Or at the very least make it fairly easy to suspend disbelief and avoid compromising the whole ancient Rome setting? This is an earth-like world with basic Roman technology (+steam ships!) There may be other steam powered engines or not, the steam power may be of any type and may be relatively primitive but should be practical (so no aeolipiles). I would rather not use magic as this makes the question trivial. edit further references added This article in reddit is very relevant: <https://www.reddit.com/r/AskHistorians/comments/1k30h1/could_the_romans_have_build_a_steam_engine_the/> Here is a reference to the transited work by Hero showing fairly extensive knowledge <https://www.reddit.com/r/AskHistorians/comments/1k30h1/could_the_romans_have_build_a_steam_engine_the/> <http://web.archive.org/web/20120211202905/http://www.history.rochester.edu/steam/hero/section74.html> [Answer] TL;DR - Romans would be able to build some riverboats with atmospheric-pressure engines, the main obstacle is understanding of physics, not some technology. 1. Building a simplest steam engine is not as hard as people tend to think. Boiler may use [atmospheric pressure](https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine) and be made from copper and lead(upper part) - that's exactly how first boilers were made. Main increase in efficiency of steam engine in 18th century came not from increasing pressure, but from using separate condenser - making it requires understanding of physics, not some high technology. Cylinders were [made by hand](https://dl.dropboxusercontent.com/s/xww002gbv9u2mvn/041.gif) and leaking of steam was prevented by winding [rope around piston](https://dl.dropboxusercontent.com/s/sl2alv3jzup0ohf/521px-1830s_beam_engine_piston_with_rope_seal%2C_Coalbrookdale_Museum_of_Iron.jpg). Wood fuel became quite expensive at late Middle Ages, but in Roman times most of Europe was covered in forest so at northern borders of the Empire fuel was dirt cheap and even in Rome it was mostly cost of transportation that formed price of fuel. Also first engines valves were hand-operated, though automating that proved to be easy enough(funny, but it was less fuel efficient that human operator). 2. Romans had quite an industry dedicated [to mine draining](https://worldbuilding.stackexchange.com/questions/96293/what-methods-might-an-ancient-civilization-take-to-extract-fresh-water-from-grea/96305#96305) so they would pay for draining steam engines. That's how first engines are likely to be used. 3. So it is technologically possible and economically feasible. The problem is to understand physics enough to make them. For example understanding workings of pressure is not as simple as it may seems - otherwise [Magdeburg hemispheres](https://en.wikipedia.org/wiki/Magdeburg_hemispheres) or Pascal's [experiment with barrel](https://en.wikipedia.org/wiki/Pascal%27s_law) would not become so famous. The notion of [latent heat](https://en.wikipedia.org/wiki/Latent_heat#Specific_latent_heat_for_condensation_of_water_-_in_clouds) is quite hard to get as well, it's understanding was crucial for Watt's invention of separate condenser. The required theory leap would be tremendous, frankly I don't see Ancient Romans making it. But if we assume that they made it somehow or were helped by time-traveler then they can build the engine. 4. But there is big difference between some Fulton's "[North River Steamboat](https://en.wikipedia.org/wiki/North_River_Steamboat)"(100 tons displacement and 20 h.p.) and ocean going steamship([Great Western](https://en.wikipedia.org/wiki/SS_Great_Western), 2300 ton, 750 HP). Making river-going steamboat is withing Roman technology level. Ocean going steamship requires [technological revolution](https://en.wikipedia.org/wiki/Henry_Maudslay). P.S. [Aeolipile](https://en.wikipedia.org/wiki/Aeolipile) is completely useless because of extremely low efficiency. [Answer] The truth is they already have it; the Greeks developed the Hero steam engine (a simple sphere on a spit so to speak, that you could put some water in and place over a fire, with 2 exhaust ports opposite each other that allowed the steam to escape and the ball to spin) - they just never developed it further. Roman ships were sturdy, and they were great traders. There are 3 reasons they didn't develop steam power for their ships; 1) Human labour - why invest in coal, expensive machinery et al when you can get humans to row? (All you need is food, but you already need that for the rest of your crew - a single resource to load up) 2) Sails - wind power was reliable enough in the Mediterranean. 3) Military focus - ships were for trading, not really for fighting. The Romans were more focused on infantry and land fighting Ultimately, if you want your 'Romans' to get into steam power for their ships, make rowers more expensive and make sea power more important. Having unreliable winds at sea would also help. Slaves would still be needed for coal mining and the like to support this technology. The real issue with steam power though is converting the energy to propulsion. In Mark Twain's time, this was done with paddle wheels. It wasn't until the end of the 19th century that the 'underwater screw', or propeller was invented. That said, using steam in military applications would have eventually led to an earlier development of this I'm quite sure. The other point coming up is the increased cost of metal in ships with steam power. This is a good point and also why Roman mechanisation would have more likely relied on spring technology. Their fifth legion (effectively their engineering corps) used to build large weapons that launched massive arrows that were launched using cords made of bovine tendons that had been dried in place. That kind of energy storage would have been more likely for their ships as well. [Answer] This is a very interesting question, because it shows how the world is all interconnected. Could the Romans develop steam engines? Let's look first at the technological requirements and their implications. ## Technological requirements The Romans knew perfectly well that there's force in steam. There were even some crude demonstrative devices, such as the aeolipile mentioned in the question. So what more was needed, from a purely technological point of view? * First, they needed fuel. The classical Greco-Roman civilization used relatively little fuel, and that fuel was wood and charcoal. They used little fueld because they lived around the Mediterranean, where winters are mild, and they lived during a warm period. The Mediterranean region has few extensive forests, and it has essentially no mineral coal. Since there is no coal around the Mediterranean, the Romans had a very vague idea of what coal was, or how to use it. They knew that in Britain one could find some black rocks which burned, but that's about all they knew about coal. But let's say that after somebody building the first engines, some Roman engineer returning from Britain would have experimented with coal, and the Romans would have pushed northwards to tap the extensive coal reserves in Britain and Gaul. So fuel is not such a big deal; it's perfectly possible to imagine Romans mining coal in Britain. * Second, and here we come to the really difficult technological problems, they would need metal and metalworking techniques to make the engine. This is a big problem. The only suitable metal available in those times was bronze; bronze is definitely not cheap. Why not cheap iron? Well, the problem is that in Roman times they knew how to cast bronze, but nobody had ever seen molten iron, much less attempted to cast it. Bronze remained the only metal suitable for casting for a thousand years after the fall of the Western empire; that's why cannon were made of bronze up to the dawn of the Modern age. Remember that in the classical world metal was used on a much smaller scale than in the Renaissance and the Modern Age. Metal was precious. And metalworking techniques were also problematic. The Romans did not have lathes able to machine metal; all they had was hand-powered lathes suitable for turning wood. The first lathes able to machine metal appeared (again) one thousand years after the fall of the Western empire. No lathes means no (reproducible) screws and no way to make accurate cylinders or pistons. Making a steam engine without accurate cylinders and pistons is non-trivial; yes, a crafty artisan could have made one cylinder and one piston, at a great cost, but this does not a navy make. * But the killer problem is metal pipes. They just did not have the technology to make high(-ish) pressure metal pipes. The only metal pipes which they knew how to make were very low pressure lead pipes; don't try to pipe live steam through one of those. Why are pipes important? Without high(-ish) pressure pipes one can make only an [atmospheric engine](https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine), like Newcomen's original (1712). This kind of engine is suitable for pumping water out of mine shafts and little else. ## Implications of the technological requirements One can of course imagine the Romans solving the technological problems. (Or more likely the Greeks, but then by the 2nd century the Greeks were fully integrated in the empire, which they no longer perceived as an alien domination but rather as the natural culmination of the history of Greece.) The question is then, what kind of world would it have been? Would it have preserved the essence of the classical world? I would say no. The kind of technological advancements we are speaking of imply a world with a highly qualified workforce, with an intense market economy, with systematic technological training, with widespread use of metal parts, with precise measurements... This is not the classical world. It just isn't. Could they have done it while preserving something of the classical world? Yes, of course! After all, we did it -- we still have senators, who (in the U.S.A.) meet on the Capitol hill, we still have tribunals, and (in many European countries) we still have prefects and quaestors, and our languages are full of Latin words. If you are content with a world which preserves some (maybe most) of the forms of the Roman world but little of its essence, then yes, this is imaginable. ## So why didn't they? But the Romans did not develop the technologies necessary to make steam engines. They did not develop the kind of intense market economy where steam engines would have been useful. Why? Because they couldn't. The Romans did invent the state in the modern conception of the word, they did invent the concept of uniform laws, and codes, and bureaucracy, and public service, and public infrastructure and many other aspects of civilization which in the fullness of time made the modern world possible. But one thing they did not invent -- a functional and stable mechanism for the transfer of power. Peaceful transfer of power was always a goal: most emperors were decent people, who really strived to preserve and develop the empire. Most of them actually succeeded in transferring power to their successor peacefully; for example the chain Nerva–Trajan–Hadrian–Antoninus Pius–Marcus Aurelius (the adoptive Nerva-Antonine dynasty, the "[five good emperors](https://en.wikipedia.org/wiki/Nerva%E2%80%93Antonine_dynasty#Five_Good_Emperors)") provided stabilty and good governance for an 84 years, almost a century, for 96 to 180 CE. But once in a while the transfer of power failed, or the successor was poorly chosen, and havoc ensued. So the empire had periods of peace and development -- under the Julio-Claudians, under the Flavians, under the Nerva–Antonine dynasty -- and periods of anarchy and civil strife. And in the 3rd century one of those periods of anarchy -- the [Crisis of the Third Century](https://en.wikipedia.org/wiki/Crisis_of_the_Third_Century) -- tilted the balance too much to the side of darkness. The empire was fatally wounded; it would never recover. It could have been avoided, especially in fiction. In fiction, one can always make [Commodus](https://en.wikipedia.org/wiki/Commodus) a good emperor; one could imagine a rule establishing that imperial succession must go to an adopted heir; or at least one could imagine the Romans instituting legallythe office of emperor and making it hereditary. (One of the big issues with the Roman empire was that before [Diocletian](https://en.wikipedia.org/wiki/Diocletian) it was not legally and empire and did not legally have an emperor; the state was officially a republic, and the men whom we call emperors ruled by cumulating key positions in the state; it's complicated, but basically they cumulated the position of speaker of the Senate, commander in chief of the army, high priest, and most importantly tribune of the people.) ## Key points * You must make the economy of the Roman empire much more intense; steam engines are no use in a sleepy economy. * You must somehow overcome the Greco-Roman disdain for artisans; maybe have Alexandria develop into a hotbed of industry, with Rome forced to compete, I don't know. * You must avoid the crisis of the 3rd century at all costs, even if that means instituting the [dominate](https://en.wikipedia.org/wiki/Dominate) early. * You must imagine a chain of unlikely but not impossible inventions... * And as a result you will get a world which resembles the classical Greco-Roman world a bit, but it's quite different, and you will have changed everything to follow. There will be no Middle Ages, no Islam, no British Empire... [Answer] Steam engines require an industrial economy. Even Mark Twain's riverboats had a huge amount of iron in them from a Roman point of view. (Foot diameter pistons, multi foot stroke...) You need a way to produce and cast iron in multiton lots. That means you have to have ways to heat it. That means coal and coke. England was able to bootstrap an industrial revolution with large forests that made good charcoal, and some deposits of coal that were near or at the surface. The steam engines drained the mines to get deeper coal, allowing more engines and railroads to be built. Rail allowed moving coal and iron ore from further apart locations. Even so, steam engines were in widespread use on land before they were applied to ships. Ship use required higher pressures to allow both more efficient use of fuel, and to get the engine to a reasonable size. One historian commented, "You can't railroad until it's time to railroad" That said: The Romans were in Brittania for several hundred years. Put the whole industrial revolution at AD 200 [Answer] Walking beam pressure pumps (which used cylinders and pistons) date to the 3rd Century B.C. (they used bronze, of course, but it would have worked perfectly fine for steam engines). The crank (sun and planet gearing was used in early steam engines to get around Pickard’s patent on the crank; British patent law of the time allowed someone to patent things that were already in use) dates to at least the 1st Century (the Nemi Ships used them in their bilge pumps) Flywheels predate civilization, and valve technology sophisticated enough for a water organ could have come up with valves for a steam engine. Putting the pieces together in the appropriate combination was beyond them, for reasons others on this thread mentioned, but all the necessary components for making small- to medium-sized steam engines were available to the Romans. [Answer] They didn't have the metallurgy, the machining skills, or the knowledge base to develop a practical, economical steam engine. The first practical steam engine was the [Newcomen engine](https://en.wikipedia.org/wiki/Newcomen_atmospheric_engine), which depended upon an invention that the Romans did not have: the cylinder and piston, to translate the partial vacuum from steam condensing in an enclosed container, into power. The piston and cylinder was an idea that was first developed by Otto Guerickie as the vacuum pump, and he got the idea from an unknown inventor who had created a household fire extinguisher using a cylinder and piston as a water pump. Nor did the Romans have a planetary gear system to translate the push and pull into rotary motion, invented by William Murdoch. True that the Greeks had developed a simple steam engine with a spinning ball, but that design did not scale up easily (no bearings that could allow a large ball to spin efficiently, no metals that could withstand the higher pressure and temperature), nor did they have a way to pump water into the engine while it was running under pressure (also requiring a cylinder and piston), so it wouldn't have had much endurance. And finally, there is the knowledge base to consider. In Roman times, metalworking was confined to hand beating bronze, copper, and iron into shapes. You can make a good sword and shield, but you can't make a practical steam engine like that. Consequently, even the idea of using steam or anything other than human, animal, water wheel, or wind for power, would have been beyond even the brightest minds back then. Theoretically, Romans could have created early firearms: they had the raw materials for both black powder and bronze cannon barrels... what they lacked was the knowledge base that such a device might be possible. [Answer] Essentially, they would have to get rid of slavery - something they never did. All the "economy" of the Empire was built upon such institution, and if anything, their navy was even more predicated on it than anything else (save perhaps mining). Their boats were moved around by oars, sails being a mere supplement (their sails only allowed navigation leeward). This posed extreme limitations to their technological progress. Since slaves don't earn wages, there was no pressure to lowering wages by improving productivity, so there was very little need for technological creativity, and even less to put such creativity into "economic" enterprises. Also slaves typically cannot be trained to improve their abilities - there certainly were skilled slaves in all trades, but this depended on the capture and enslaving of already skilled artisans, not on catching unskilled workers and then teaching them a trade (plus there will always be some underuse of slave skills - think 12 Years a Slave, where a skilled musician is enslaved to perform utterly manual and unskilled labour). Such problem, if anything, grew increasingly as the original sources of skilled slaves - Greece and other already "civilised" regions - where integrated into the Empire, leaving it with only "barbarian" unskilled enslavable reserves of manpower. Imagine trying to convince the owner of a Roman trading ship that he should replace his already paid for slaves with an equally or even more expensive machinery that then would need a much improved set of workers, that he would not easily, if at all, be able to procure at the slave market, resulting probably in needing to pay wages. Why would he pay twice for his power (machinery and then wages), if he had an already paid for crew? In such an environment, not only technological innovation was stimied, but even more the integration of any eventual advances into the productive system. The intellectual powerhouse of Classic Antiquity - the Museum at Alexandria - certainly provided a few inventions, but those were at the service of military engineering, not of improvement of labour conditions or of labour saving in agriculture, artisanship, or commerce. So, a social revolution - the abolition of slavery - was a precondition. Without that, even if they had the technological ability to make a steamship, they would build it, at best, as a "wonder of the world" - something impractical, made to astonish people at the power and might of their empire, not as something to put into daily practical use. [Answer] The Printing Press You might have to have your Romans invent the printing press first. There's a ton of ideas that had to come into place before the steam engine could be viable, and the best way to trigger an accumulation of ideas is to have a way to put those ideas down and to widely distribute them. But then the question would be why the Romans would want a lot of books around. Maybe a religious movement that centered around books. (But that's been done.) Maybe books could be used for instructions for setting up colonies. Or for field manuals for the troops. Or the printing pressed could be used for creating massive numbers of fliers for propaganda. Archimedes What if Archimedes was captured by the Romans instead of killed, and he invented the printing press? That could be fun. ]
[Question] [ I am currently trying to find information about different magic systems for an RPG. There are a lot of possibilities as to what could be a potential starting point for a magic system and I recently came across some interesting information about a [magic system based on Tarot](https://worldbuilding.stackexchange.com/a/95420/28789). I'd love to find more resources about this type of magic system. This includes for example: * already existing games (video, tabletop, ...) that take Tarot as a starting point for their magic system * mythological references in our real-world that associate Tarot with magic * stories (books, comics, shows, ...) that incorporate this idea * ... Where can I look up information about using Tarot as the basis for creating a magic system to use said system in a RPG? [Answer] I highly recommend the book The [Qabalistic Tarot: A Textbook of Mystical Philosophy](https://cdn.preterhuman.net/texts/religion.occult.new_age/occult_library/Wang%20-%20Qabalistic%20Tarot/Wang%20-%20Qabalistic%20Tarot.pdf). It is scholarly, extremely well researched, and contains extensive footnotes and citations. You may also find Israel Regardie's work useful, particularly [The Tree of Life: A Study in Magic](http://www.metaphysicspirit.com/books/The%20Tree%20of%20Life%20-%20A%20Study%20in%20Magic.pdf). [Note: there is also [a revised, illustrated edition available]](https://www.goodreads.com/book/show/406212.The_Tree_of_Life). And of course, for an understanding of magic in general, [Frazier](https://en.wikipedia.org/wiki/James_George_Frazer)'s [The Golden Bough](https://en.wikipedia.org/wiki/The_Golden_Bough) is essential. (Take a look at the chapter on [Sympathetic Magic](http://www.bartleby.com/196/5.html), which is a very good primer.) Finally, [Alan Moore](https://en.wikipedia.org/wiki/Alan_Moore)'s [Promethea](https://en.wikipedia.org/wiki/Promethea) can be understood as a thesis on magic in general, and the Tarot in particular. Plus, the artwork is astounding! [Answer] The basic logic of Tarot magic can be explained as simply as this: > > If you think of a spell ingredient as something conceptual rather than > something tangible, then it makes it a lot easier to think creatively > about what you can use. > > > One item that many of us have on hand is a deck of Tarot cards. While > we often turn to them immediately as a method of divination, a lot of > us tend to forget that we can use them in spellwork. After all, a > Tarot card – whatever it may be – symbolizes some aspect of the human > existence. More importantly, you’ve got 78 cards to choose from. If > you’re someone who uses reversals in your Tarot readings, that means > you’ve got 156 symbols, or archetypes, right there at your fingertips, > just waiting for you to unleash them. By selecting a Tarot card that > represents your goal, or the intent of the working, you can craft a > simple spell that’s just as effective as one with all the trappings > and bells and whistles. > > > Of course, now you have to delve into symbolism and patterns embodied in Tarot. Let's start with spells concerning matters of the heart. > > For matters related to love, family, emotions, and relationships, you may want to choose Cup cards as your focus. Consider an Ace of Cups to represent new beginnings and starting over, a Three of Cups to symbolize celebratory events like births or weddings, or the Queen of Cups to stand in for a sensual and captivating woman. The Lovers card, although associated with love and all its trappings, is one you may want to use if you’ve got a decision to make between two potential romantic partners, or you’re trying to help someone (including yourself) overcome temptation. Cup cards can also be used to represent the element of water. > > > If that's not enough, violent action is all the rage. A mainstay of entertainment. > > Sword cards are associated with air, and they’re all about conflict. These come in handy if you’re trying to do spellwork that is damaging or destructive (as always, if your tradition forbids cursing or harmful magic, don’t do it, and you can just skip over this paragraph). A Three of Swords can bring about heartache and pain, particularly if there’s some sort of love triangle involved. Use a Seven of Swords to represent a deceitful liar in your life. The Knight of Swords will reveal the truth to those who need to hear it, whether it’s something they want to hear or not. > > > Essentially a Tarot-based magic system is all about taking a symbolic system and deploying those symbols to cast the spells you want. > > The bottom line of using Tarot cards in spellwork? If you familiarize yourself with the meanings of the cards, there’s no reason you can’t craft a perfectly useful spell with the deck you have on hand. Think outside the box, be creative, and see what you can manifest! > > > Source: [Tarot Card Spells](https://www.thoughtco.com/tarot-card-spells-2562774) One word of warning about tarot magic. > > Never use the same tarot deck for magic and for prophesy. > > > You can use one tarot deck for magic and one same for divination if > you want, but they should be two separate decks. The rationale is to > avoid creating unwanted results while trying to foresee the future. > > > Source: [Tarot Magic & Spells](https://www.magicalrecipesonline.com/2015/03/tarot-magic-spells-the-magic-of-the-fool-2.html) More can be found about Tarot magic by using a search engine and entering the search terms "Tarot magic". This form of divination is not infallible, but it does work wonders. [Answer] Persona 4 uses the greater arcana to name various "personas" (demons that are essentially strong helpers for the characters who have mastered calling upon them), but the theme ends there, since the magic attacks are Shin Megami Tensei series staples. JoJo's Bizarre Adventure Part 3 names many of the "stands" (spiritual energy beings that are basically what personas in the Persona series are based on) after greater arcana cards. Their abilities and appearances are often not based on any percieved meaning of the cards themselves, however. In the end, like @MichaelK said, there is no real world "canon" to what the trumps of a Tarot deck actually mean. All of that stuff has been cooked up by mystics and charlatans to make a quick buck off of gullible people, and no doubt it varies between person to person. @a4android did a good job putting down the most common spiel on mystical Tarot. It may be best to just come up with magical associations to the Tarot deck yourself, as most people who want to play or read the lore of an RPG aren't going to demonize its creator for having "improper" ideas of what power each spell named after a card would have, or what powers the card would bestow upon a user. [Answer] TVTropes article [Useful Notes Tarot](http://tvtropes.org/pmwiki/pmwiki.php/UsefulNotes/TarotCards) contains a list of what each Tarot card means and the thematic nature of each card including both major and minor arcana (and the gag card "The Happy Squirrel", introduced in The Simpsons to poke fun of the commonly known factoid that the Death Card doesn't thematically mean Death, but change. In real Tarot lore, it's the Tower Card that fortells Death). Their article ["Tarot Motifs"](http://tvtropes.org/pmwiki/pmwiki.php/Main/TarotMotifs) includes a list of works of fiction (and maybe real world stuff) that use a Tarot Motif. This page has a few links to other sites that feature decks of Tarot Cards that use characters from series that are not necessarily Tarot motifed, but the character fits the card themes. One of the ones I can remember off the top of my head is Pokemon. [Answer] You might want to read [The Chronicles of Amber](https://en.wikipedia.org/wiki/The_Chronicles_of_Amber "Amber") series by Roger Zelazny, where the cards serve as a means of communication and teleportation. [Answer] Yugioh has a card archetype based on tarot cards. That's a good place to look for ideas of what effects which cards could have individually. I think it's worth a look since anyone playing Arcanas is definitely trying to play a table top RPG. [Answer] Ogre Battle March of the Black Queen is a game (SNES and later re-released on Playstation) which used Tarot cards as a sort of clutch summoning system. A limited resource to help your armies edge past difficult opponents. Each card's effect was loosely tied to the card itself; for example the magician card did an effect of magical fire damage on the enemy army, the Empress card would heal your army. You obtained cards by liberating cities. Everytime you liberated a city you could draw a card; and the chosen card also gave a permanent stat change to the army that drew it. Some like hanged-man or devil gave negative effects. So it was a bit of a gamble. ]
[Question] [ I am really surprised that I can't find a question that has already answered this. I am working on a book about essentially what might have happened had a zombie plague broken out in England in about 1060 AD, right before [William the Conqueror](http://en.wikipedia.org/wiki/William_the_Conqueror) began to cause waves. To be specific: These are sort of medium-speed zombies, walking about as fast as a human in decent health walks. They require brain damage to kill- a head by itself would still be alive. Infection is spread by bites/scratches/wounds. The disease infects only humans. After being infected, the infected person shows symptoms (fever, extreme, almost constant vomiting, nausea) after a few hours, and generally turns after 36-48 hours. They don't need to feed to stay alive. They are faster at night, but only slightly. The zombies do not like water- being fully immersed in it would eventually kill them, in a matter of days to weeks. How would this affect overall civilization in England? My thoughts so far are, that the zombies would destroy isolated villages, but towns would be unlikely to fall unless an infected person made it inside, and possible not even then. Guards would be very vigilant. Religious societies might well set up sort of a "citizen's hospital" to quarantine visitors for a while upon entrance to the city. There is a fairly large precedent for religious generosity even to "untouchables" of society. The entire religious aspect is fascinating, and a large part of why I'm investigating a book about this scenario. The zombies would likely be seen as a curse from God. Because killing these "accursed" would be seen as a holy thing to do, I could well see large numbers of knights venturing forth to slay them. [Advantages of armour when fighting zombies](https://worldbuilding.stackexchange.com/questions/17309/advantages-of-armour-when-fighting-zombies) indicates they would actually do fairly well against zombies. In thinking about it, zombies are probably very easy for an army to slay- hand to hand combat against an unarmed foe whilst wearing armor. The tricky bit is that if one of your comrades got infected, you might well wake up to find the army's camp overrun. Another intriguing effect would likely be that anyone who suffered from a fever/vomiting would be killed on the spot for fear they had been turned. A siege of zombies would be really interesting. [Answer] It's rather unlikely. The basic issue is that there are very few people in medieval England. You've got 1.5 million people, mostly rural, so very spread out. Even if everyone in the country gets turned that makes for only 20 zombies per square mile. So realistically you won't get zombie hordes, you'd get the odd individual zombie wandering into places. Which is easily dealt with once people know what to look for. To spread, the average zombie encounter needs to have the "zombie infecting someone and so increasing the number of zombies" be of a greater likelihood than "the zombie is destroyed without infecting someone (or the infected are killed without turning)". That just doesn't seem likely. That's ignoring the increased proportion of people who are handy with a farm implement, and a superstitious populace that is therefore more mentally prepared to clobber a 'demonically possessed' neighbour. [Answer] A similar question was asked about the Roman Legions vs the zombies, but in this case, the pre conquest Britons would actually do a bit better in the fight, but would still be overwhelmed in the end. The standard huscarl in Harold's army would be clad in mail, protected by a conical "nasal" helmet and a kite shaped great shield, and fighting with a large Danish war axe as a primary weapon. The huscarls were elite troops with high levels of cohesion and motivation, fighting behind "shield walls", so the zombies would have a hard time getting at them. As well, the axes would deal killing blows to unarmoured zombies quite easily. The local fyrd (levies or militia would be the closest term) would have much less protection and cohesion, and would probably be the source of all your zombie infection problems. A member of the fyrd could be easily scratched or bitten, and go back to the village after the battle to dispatch the zombies. Mayhem results a few days later, and the fyrd of the next village is called up to repel the zombie horde, with similar results. What would be horrifying to the villagers and even the elite huscarls was the seemingly random nature of zombie infestations. They didn't have a germ theory of disease, so being struck by the zombie plague would seem to be sheer magic or the act of a vengeful God displeased with the local people. There would be some inkling that people with the disease should be kept out, but a carrier not showing any symptoms would probably be let through the blockade, and of course the villages and towns needed access to food and fuel (trees, in this case) so there will be lots of traffic. Of course authority was fairly weak and localized, so a guard could be bribed or subverted to let someone pass, negating the effect of the quarantine blockade. Unless someone was willing to carry out drastic measures (as in burn down the village where a suspected zombie may be), the disease will spread quickly. Even worse, drastic measures like this will only slow, not stop the disease. A zombie shambling around in the forest could pop out at any random time and start the cycle all over again, and the disease will grow and spread in a geometric progression. William will never bother to cross the channel to claim the "Accursed Isle", devoid of human population but lethal to any living human who were to go there for the next 100 years (perhaps more if the Zombie virus can stay alive in spore form ready to infect newcomers to the shores of England). [Answer] It only takes one person to make it inside a city to spread the disease easily. The success of quarantine will require that they realize how long it takes until the vomiting starts, and take extreme measures, but it is possible. I think the success of your knights' expeditions would greatly depend on just how many people get turned before everyone realizes the circumstances they are in. Your people still require food and goods, which was coming from those ioslated villages. If not a lot of people are turned - a standing army could conceivably battle and keep control of land used for food production, and protect anybody moving goods from one place to another. Yes, they would have to take those hard decisions to kill their friend who was only scratched and is now sick. However, a huge mass of undead - no matter how slow or unarmed, could overwhelm anybody with any weapon or armor. It could potentially be the same as being under siege with an enemy that will never get tired of sieging, and who only grows stronger the longer the siege lasts as slowly the zombies catch those outside of the city walls. --- The overall answer to "How likely would a zombie apocalypse be to wipe out civilization in medieval England?": It depends - mostly on how quick they are to react and how many zombies there are when the number stops going up as fast. [Answer] [Epidemiological studies](http://arxiv.org/abs/1503.01104) have shown that to successfully combat the typically-described zombie outbreak, it is necessary to eliminate zombies and the infected humans rapidly, otherwise the end result will be a world where zombies have replaced humanity. In medieval times, human life was somewhat less valued, and in the initial stages of an outbreak, people would be more likely to avoid someone obviously sick than to try and help - and get bitten, thus reducing the bite rate. The zombie removal rate could be considered to be a little higher too, especially as the outbreak continued, as it could be made a religious duty to kill the zombified and infected. Additionally, the full plate armour that knights wore would make them far more resistant to being bitten and infected, thus reducing the bite rate against said individuals, who would also be better at zombie removal. All in all, without actually simulating the outbreak as the authors of the paper I cited did, I can guess that there is a fairly even chance that either the zombies or humans will win, probably depending on the speed with which the authorities act to control the outbreak. In either case, there is quite likely to be a lot of corpses, and if the humans win, the clean-up isn't likely to be pretty. The epidemiological study shows that cities are dangerous places to be, that it's far safer to remain out in the countryside. That is the case in modern times, and will be just as valid in medieval times. [Answer] In Medieval times defensive structures were very common, and while not everyone had a stone castle there were Motte and Baileys that people could go into when someone was attacking. They had a bailey (farm bit) a motte (a hill) and a keep which was the wooden castle on top of a motte.The whole thing had a palisade fence around it and a moat around that so if it wasn't airborne communities of lords and peasants could continue to survive in these fenced-off areas. Unfortunately Motte and Baileys only took off in England after William the Conquerer came to power and had a castle building-spree. So if you hold onto those zombies for another twenty years, society has a better chance of surviving. Besides the Mottes and Baileys, I think people would manage the zombies fine. After the vikings, slow, weaponless people probably wouldn't be that scary. <http://www.hinckleypastpresent.org/images/hinckleycastle01.jpg> In the case that England does collapse CYMRU AM BYTH! Cymru [Gruffydd ap Llywelyn!!](https://en.wikipedia.org/wiki/Gruffydd_ap_Llywelyn) [Answer] Finding The Dominant Problem Don't underestimate the zombies. In most situations, the key to predicting the consequences is to identify the one or two dominant impacts that a situation will have on a population and to ignore all third and higher order effects. Lots of the problems that other answers to this question have solved are basically third and higher order effects, however. The single greatest threat posed by a medieval zombie apocolypse is the threat that they would pose to farmers doing their work and to crops in the fields, as explained at greater length below, something that other answers haven't given much thought to addressing. Less Critical, Later Order Problems Keeping zombies at bay in fortified walled cities, castles, monasteries, towns and even enclosed country manors, and fortified caves might not be much of a problem. Solutions like moats would be popular (and for backstory, Copper Age and Bronze Age Iberia was [full of walled enclosures that often, perhaps even usually featured moats](http://portugueseenclosures.blogspot.com/), so perhaps zombies were a particular problem in Portugal and Spain for some reason). England has abundant supplies of water that would make it unnecessary to be vulnerable around fresh water supplies. And, defeating zombies militarily in planned engagements with armored soldiers and calavry might work, against an ill armed, not terribly fast moving, ill coordinated foe, however deadly they might be if their infection is passed on. But, feeding everyone during the zombie apocylopse would be a much more daunting task. Feeding The People Most People In The Middle Ages Were Poor Rural Farmers In the Middle Ages, the vast majority of the population (70%-90%ish) was engaged in farming as serfs on feudal estates and herding on unenclosed pastures. And, it is not practical to have a very large share of workers in a field wearing armor or carrying weapons in addition to farming tools while working the fields. Probably only something like 1% to 5% of the population could be spared as anti-zombie soldiers. Also, only a small minority of people could afford to use horses for transportation, so most serfs and free peasants would have to live pretty close to the fields that they work, greatly limiting the number of people who can live in fortified urban centers. Recall that feudalism was necessary in the first place because kings lacked the logistic capacity to rule their kingdoms directly, rather than through intermediary noblemen who lived cheek by jowl with their subjects. High population densities were simply not economically or technologically viable for the most part. In short, there are real limits to the viability of fortress/quarantine solution. Keeping Watch Given that zombies aren't particularly fast, probably the best strategy for farm workers would be to put some older children who are still relatively small and not too useful in hard labor in tree tops or artificial lookouts to keep their eyes on the lookout for zombies, and have them signal if they saw any coming, so that everyone could jog to the nearest farm house or purpose built rural zombie shelter before the zombies arrived and from there ring a loud bell or drum to summon assistance from the local lord's soldiers. The strongest farm workers would form a rear guard with their tools as improvised weapons, as the children scrambled from their lookouts and fled for safety at a higher speed than some of the older farm workers, to join the less fit farm workers fleeing while the rear guard covers them. [Ley lines](http://ikipedia.org/wiki/Ley_line) historically were probably established deliberately by prehistoric Britons as a series of watchtowers connected by line of sight to provide an early warning system and this too could be integrated into the zombie alternative history. How Can Crops Be Kept Safe? There is also the problem that crops in the fields are vulnerable to trampling by zombie hordes, even if the zombies aren't doing so intentionally and have no use for the crops themselves. Farming requires sustained peace and order for many months at a time, because the growing crops can't be moved until harvest time two or three times a year, leaving months at a time when they are vulnerable not just to weather and animals but to destruction as wandering zombie hordes trample them. It is all good and well to hide in a castle or rural zombie shelter or fortified farm house or manor for a few hours or couple of days while the zombies in the neighborhood move along. But, if you hide in your fortified place of safety while your crops are ruined, the zombies will have killed you as sure as if they had actually eaten your brains. Only starving to death takes longer and involves more sustained suffering as you watch children and older people die first, and those in between struggle to hold on with food shortages that make them vulnerable to diseases and zombie attacks. Yet, it would be far too expensive to grow any crops but a few high value ones (such as herbs and spices and maybe some berries or orchards or vineyards) or that don't need light and can be grown in cellars (such as mushrooms) within fortifications. If the English people are going to survive, they need better solutions than high strong walls that are expensive to contain large areas with in order to protect their crops. Swamp Buffers For Fields One attractive solution to protect more everyday crops would be to drain the interior of bogs and moors and swamps, while using undrained perimeter areas as wet buffer zones to protect the crops from wandering zombies. Alternately, rivers and streams could be intentionally diverted to flood perimeter zones around farmers' fields, a bit like Asian farmers flood rice patties, to create new buffers and wetlands (with the downside of providing a home to insects and other vermin who also pose a public health threat). Maybe access could even be via a short flat boat trip or a plank walkway that could be pulled up if zombies were sighted. Big Cats To Protect Fields Another way to keep fields safe would be to encourage top predator species (felines would be preferred because they don't eat grain themselves) to patrol your territory, at least if they could prey on and/or eat zombies. Lions and tigers could come to be known as protectors of the land, rather than merely as threats to livestock, and might learn to prefer to hassle zombies who would generally be unarmed, not as fast as them and relatively stupid, to trying to make uninfected humans their prey. This could also provide evolutionary insights into why zombies move faster at night when large felines are more active, than during the day. Conclusion If you could find a sustainable way to grow food free of significant zombie interference, life could go on, but I'd suspect that you'd see rapid population collapse primarily due to impaired horticultural production, rather than direct losses to zombie infection and attacks, in places where a quick solution to keeping zombies out of the fields could not be devised fast enough. This population bust would impair high culture and would strengthen the hand of serfs vis-a-vis their feudal masters, because there wouldn't be enough serfs to tend all of the land. Serfs would gain more freedom and rights during the zombie era in England. A zombie outbreak might cause democracy to emerge earlier than it would have otherwise. [Answer] How likely? Not very likely. To start, people were probably more used to death and killing back in 1060. People now are (no offense intended toward anyone) squeamish babies in comparison. The average medieval peasant probably hasmore combat effectiveness than a modern western citizen. Technology of the time gave you two options: Riding an expensive, hard to maintain horse or walking. Old Roman roads were decaying and had been for a while with little to no maintenaince. Since you specified that these zombies be undead I have to assume that they rot. If not at the same speed as a regular corpse at least at some decent rate. Their speed might be impaired in 20 weeks or so assuming a severely slowed rate of decomposition. This is surely enough time for an uninfected lord or knight to ride horseback to the neares town and alert them. The will rebuff him at first, but as more and more towns slowly collapse to infection, a religious crusade will begin against the undead. I would love to see a zombie horde of say, 10,000 beat an army of well informed English knights and longbowmen. In Max Brooks' [Zombie Survival Guide](http://rads.stackoverflow.com/amzn/click/1400049628) he depicts a similar situation. The armies of England would dig deep trenches around their camps and let the hordes fill them. Not very likely as you pointed out. I would bet my money that some superstitious nut cases would begin spreading word that [the Jews did it](https://en.wikipedia.org/wiki/Black_Death_Jewish_persecutions). There would be even more. Going to graveyards would be prohibited because noone would know it is a virus; avoid the dead and you wont join their ranks. Lords might see the chaos directly after the threat as a chance to decentralize the country even more, perhaps even declare independence. When someone died (regardless of what killed him) it would be mandatory to cut off his head and burn it/cut it up/throw it into a river. If whatever disease causes the zombies can survive long enough in water this might become a serious threat of infection to major cities like London. A holiday might be created to "to celebrate Gods' victory over the undead infidels." People would be even more restricted which could result in more peasant uprisings as their only fibers of freedom are removed. Now that we know what some of the societal implications might be, lets explore how to make the apocalypse happen. As pointed out in oher answers, there needs to be a large number of zombies exponentiqlly spreading the infection. You could outlandishly have aliens infect large numbers of people in major cities and towns (Why only England, though?) or you could more realistically make it some sort of previously undiscovered waterborne neural parasite. I like te latter more. I have more to say but not enough time. I will update the answer later. ]
[Question] [ Within my setting, there is a large empire which includes all of civilized humanity, within a late medieval setting. There are no notable external forces, so any and all conflict has always been from within the empire. Previously, the empire was well respected and honoured by all, each of the many kingdoms swore fealty to the emperor, and presented to the emperor a portion of their armies as well as their money. However, that all changed when there was a succession dispute, however, the true rightful empress was dethroned and exiled. Now, an emperor, who was the deposed empress's sibling, is in control of the empire. Now for the question, how do I allow the kings to fight each other, while still swearing fealty to the empire, AND make it so that the emperor has little to no martial power? Things to note: * Late-medieval tech levels all around * Low powered magic is common, but high powered magic is very rare * There are various races of [varying sizes](https://worldbuilding.stackexchange.com/questions/9507/what-should-architecture-of-an-imperial-capital-be-like-in-order-to-accommodate) and capabilities within the empire, all of them are political equals to one another and are full members of society. * Humans do not outnumber the rest of the races. Humans will make up about 25% of the population, but each other race will then be about 3-6% each. * The emperor is human. * [The many races are more nationalistic than racist.](https://worldbuilding.stackexchange.com/questions/9968/how-to-promote-nationalism-for-a-multi-racial-kingdom-against-other-such-multi) * [Gender-based race are in full swing](http://tvtropes.org/pmwiki/pmwiki.php/Main/GenderEqualsBreed), when a male X marries a female Y, all boys are X and all girls are Y. * If it was not obvious before, [feudalism](http://en.wikipedia.org/wiki/Feudalism) is in full swing here. A majority of any landed ruler's troops and money would have to come from his/her vassals * As for gender succession, it is going to be [absolute primogeniture](http://en.wikipedia.org/wiki/Primogeniture#Absolute_primogeniture), which is to say, the oldest child inherits, male or female. Also matrilineal marriage is very common, when the female is of nobler blood or higher rank. PS: Most of these things are based from me playing [crusader kings II](http://en.wikipedia.org/wiki/Crusader_Kings_II), so feel free to correct me where needed. Sorry in advance. EDIT 1: Do note that the scope of the empire has slightly shrunk from all of humanity to just all civilized humanity. This means that there are barbarians and the like outside the empire. [Answer] hmmm that's an intriguing set of problems. So the emperor is not militarily powerful, but the empire still stays intact. There is plenty of room for the kings under the emperor to fight. There is a strong nationalist loyalty powered by the general populace. I think the primary solution is to provide the emperor some sort of political, (or other), power that makes him an undisputed threat to any king. A threat to the king regardless of the martial power of that kings kingdom. I would recommend one or more of the following: 1. The emperor has an elite & powerful force of assassins supported by another force (or the same force?) of amazingly effective spies. This force is so effective that a king deciding to secede or otherwise undermine the emperor is typically found dead with a message indicating the reason for his death within a day or two. The message & it's details regarding the plans of the king would strike deep fear in the hearts of the heirs to the throne, councilors of the king who was assassinated, etc.. 2. The emperor has a small group of powerful magic users (since magic is rare this would grant him the opportunity to engender an impressive amount of power in itself, mostly in the form of fear of the unknown [or known] powers of this small group). This small group could effectively allow the emperor power in whatever way you choose from being effectively the same as the assassins/spies to turning the minds of the kings to unswerving loyalty regardless of what they thought of the emperor prior to becoming king, (through magic in the crowns, through powerful & complex spells in the land of the kingdom itself, etc...) 3. The emperor has absolute control of a vital resource which he uses to control all of the kingdoms. This could be used to threaten any kingdom not conforming to the desires of the emperor. The fear of another kingdom taking control of the resource could allow the emperor to manipulate each kingdom into protecting him and the resource, (perhaps by getting each kingdom to provide equal sized forces to protect the resource simultaneously?). 4. The last thought is some form of manipulation of the nationalist loyalties of the people of each kingdom. Possibly a set of competitions/statistics that the emperor collects or controls, keeping each kingdom focused on competing with each other kingdom and NOT focusing on controlling the empire as a whole. The citizens of each kingdoms severe nationalist loyalties would even allow control of the king if it where felt by the vast majority of the people of each kingdom. This manipulation could be expert political & propaganda/marketing methods, powerful magic, etc... Interesting idea & good luck! [Answer] Well, a good solution would be to take from a solution by Terry Pratchett, namely, the solution of Lord Vetinari. Your emperor doesn't have to be powerful in terms of military might or power, so long as he is a blasted good politician and arm twister. The reason why I think this would work is because your Empire actually sounds pretty much like a larger version of [Ankh-Morpork](http://en.wikipedia.org/wiki/Ankh-Morpork), where there are a lot of different races and a lot of different people vying for positions of power, and there is one person who runs it all from the top. In both cases, the topmost person is but a measly human in a land full of fantastical creatures, and in both cases magic is quite rare. So, I would venture to say that the solution could be quite similar - No one would move to overthrow the Empire/Emperor so long as it is irrefutable fact that the empire could not run without them. They are so good at manipulating people and running everything that it would be unthinkable for them to not be doing it. People keep him there because they don't believe anyone could possibly do a better job, not even themselves. TL;DR: In Ankh-Morpork, do as Lord Vetinari does. [Answer] It was quite common for the Emperor to become just a figurehead. There are plenty of example in human history: Han dynasty, Abbasid Caliphate (although a Caliph is not exactly the same as an Emperor), the Ottoman Empire... The Empire can survive for quite some time but it does make it weaker against invaders. As long as there is no external threat, they can survive as long as the Empire members do not try to declare independence. With a weak emperor, that might happen at any time and there is not much that can be done to prevent it. This rarely happen when everything goes right but only in difficult times like economical problem or political crisis. The only thing left for the Emperor his is legitimacy, what the Chinese call the Mandate of Heavens. The members are more likely to stay if there is order in the Empire. You did say that the last Empress has been replaced by someone else. I suppose that the new emperor has the support of a large portion of the aristocracy? Otherwise, if he doesn't have a lot of allies, the Empire is in great trouble. He risk a civil war or perhaps worst: the Empire dismemberment in total indifference. > > There are no notable external forces > > > That doesn't mean anything. The Mongols were unknown to Chinese people until it was almost too late. The Jin, a nomad people closer to Mongolia, did not have any mention of Mongols either. With a good but small cavalry, nomadic people conquered most of Asia. They came out of nowhere and incorporated more and more tribes as time advanced. And that, you can understand if you played Russia in CK2 while being defeated easily by the armies of the steppes. I controlled about a fifth of the map and I was annexed. The threat should not be underestimated since the Empire is very decentralized. In conclusion, whatever he does, your emperor is just buying time because the odds are against him. A bad harvest, an incompetent successor, an invader (invaders always hit when your down) and he's done. He could try to regain the powers from the aristocracy but that alone would deserve it's own question/answer. But I'm going to add this section from my other answer: One way to do this (this might become a bit off topic so I will explain briefly), is to make the aristocrats useless. Without coordination, these lords are separated when it comes to fighting an enemy. Being members of the Empire is no grantee to have help form the others. The Emperor might have the moral authority to gather allies in order to defend the Empire. But, every time a local lord must depend on the leadership of the Emperor to defend it's territory, he is at risk of being marginalized, slowly. With a constant threat form the nomadic tribes nearby, this system of defence can become institutionalized (made official). Meaning that it could become an automatism that the Emperor lift troops and money from it's members to defend the Empire. It also mean that the Emperor could take the right to collect taxes across all the Empire. The lords might not like it but they can't do much about it since they can't defend their land appropriately by themselves. That is more or less what happened in France by the of the reign of Louis XIV. The nobility is still there but aside form some ascetic powers and some privileges (like not paying taxes), they are powerless. [Answer] The [Sengoku Jidai](http://en.wikipedia.org/wiki/Sengoku_period), the Japanese Warring States Period, saw something like this. There was technically an emperor, but he was mostly helpless in the affairs of people. Warrior monks and Samurai were the political and military powers of the day, not the Emperor. As a side note, Extra Credits has an [entertaining telling](http://youtu.be/hDsdkoln59A?list=PLhyKYa0YJ_5Aq7g4bil7bnGi0A8gTsawu) of this period. Basically, the people with the real power duked it out, until the strongest (luckiest? cleverest?) ousted or strong-armed all the competition until the empire was re-established. [Answer] I would argue in a similar vein as to @Feuarie, but on a somewhat different plane. Political machinations are a good way of doing it. Straight up and down, behind the back, treacherous intrigue can result in a stalemate where nobody wants your ruling power, but nobody wants anybody else to win the position either. A similar problem occurred in the Sengoku Jidai, where the Oda clan rose to power as enemy clans refused to ally against them. Think the "pirate king" in Pirates of the Caribbean for another example. So, your position of emperor lends some air of legitimacy to martial manoeuvre, even if no actual might. Any warring king would relish that legitimacy, as well as the other benefits the office might hold. A powerful new emperor might rally the less aggressive nations to them in an effort for peace. They may be able to levy taxes or pull on other resources with the office in hand. Thus, the kings would be desperate to seize it, but equally desperate to keep enemies away. The emperor in place might use this to his advantage, pointing the armies of others where necessary when threatened, or the kings may intrigue to keep others away from him while trying to curry favour. ]
[Question] [ Imagine a planet like earth, but windier. Not pick-up-a-house-and-drop-it-on-a-witch windy; let's say just give-trees-a-hard-time windy. I'd like "high winds" (defined by the United States [National Weather Service](https://en.wikipedia.org/wiki/National_Weather_Service) as 40-57 mph, or about 64-91 kph) to be fairly common most places on land. It doesn't have to be constant and doesn't have to be uniform. I'm just looking for a way to up the overall wind dial without rendering my planet uninhabitable. What are my options? What's fair game: * Changes to the land-ocean ratio and the arrangement of the continents * Changes to the atmosphere, as long as it stays breathable for humans * Changes to the planet's rotation period, as long as things stay habitable for humans and there's a day-night cycle * Changes to axial tilt, again, as long as things stay habitable * Changes to overall climate, such as ice ages or global warming, as long as... yeah, habitability What I'm not looking for: * Changes to the star * Changes to the planet's size, composition, or orbit * Tidal locking * Anything that that makes the planet uninhabitable without fancy technology [Answer] ## Without serious modelling or making the actual changes, you will never know the answer. Climate is very hard to predict. Despite the large amount of effort for climate modelling based primarily upon our concerns about anthropogenic climate change, the models vary considerably in the expected effects and do not predict past history well without considerable tweaking of the result. For example, cloud cover has been omitted from global models (GCM) because it is so hard to model - even though it is known to be an important contributor to climate. Our GCM's push the limits of our best supercomputers, which contributes to the limited value of our GCM's. Winds are generally considered to be driven primarily by temperature differences, both diurnal and equatorial vs. polar, and Coriolis effects. Some ways you could increase temperature differences within your constraints would be to increase diurnal variation by slowing the earth's rotation, reducing cloud cover (allowing heat to escape more rapidly at night). Reduced atmospheric moisture also reduces the specific heat of the atmosphere allowing the temperature to change more rapidly - so a two-for-one benefit. By reducing ocean coverage you likely reduce atmospheric moisture and also gain a direct benefit by reducing the temperature moderating effect of the oceans themselves. Increasing the axial tilt would increase the polar/equatorial temperature difference. Reduced rotation speed, reduces to Coriolis effect. You can't predict the net effect of changes without an accurate model. There are tradeoffs to consider, e.g. increasing the axial tilt to 90 degrees would eliminate diurnal variation. For the purposes of story telling, you really don't need the answer, at most you just need a plausible answer. If you tell the reader that wind speed average 60 kph with frequent gusts to 90 kph and focus on the story you'll accomplish your purpose. If you want to explain why it's so windy just do so. As a reader with a technical background I would be much more interested and skeptical in what caused the planet-wide changes to rotation speed, and axial tilt, and ocean coverage than I would the resulting difference in wind speed. Not that I have any difficulty enjoying a story where parameters like tilt and rotation speed changed without explanation. But if there is a explanation I much prefer it to be believable. [Answer] Flat, dark-colored, stony deserts. [![turpan](https://i.stack.imgur.com/98VpZ.png)](https://i.stack.imgur.com/98VpZ.png) <https://www.youtube.com/watch?v=6YmxPyC2STs> [A wind-albedo-wind feedback driven by landscape evolution](https://www.nature.com/articles/s41467-019-13661-w) > > Wind deflation led to the armoring of the land surface, which resulted > in an increase in mean wind speeds and gustiness. This informs us that > albedo, which is determined through surficial geology (in this case), > can have a positive feedback on wind speeds, with the initial albedo > perturbation driven by wind erosion > > > Globally, windy, sediment-, and vegetation-starved desert landscapes > can evolve to stone-armored surfaces if supported by the surface > mantling bedrock... Finally, as recent work has pointed to this > process acting as a primary driver of wind erosion on Mars > > > The whole article lays it out. Wind moves away whatever it can move away over the years - sand and dust. It loses energy in the process. Once that stuff is gone, stones are what is beneath. The stones cannot be moved and so the wind speeds up. The action of wind over rock produces "desert varnish", darkening the rock. As rock darkens, albedo falls, increasing heat absorption which increased wind speed. It is a feed forward loop. The end result looks like Mars and the Turpan area of the Gobi desert (where the linked research took place) does look like Mars. Although if you look on Youtube you will not see many Marsscapes but instead well made Chinese videos with young tourists looking at tourist things. Those videos could be of use to you too because they show how people can live in a desert like this. I think you will need oceans somewhere in your world because the oxygen has to come from plants somewhere and there are certainly none here. An interesting idea would be a Barsoom like world. The oceans are dead or gone. I think the red Martians had oxygen producing factories. Another alternative would be relic oxygen from before the oceans died. It persists in the atmosphere because there is nothing much to oxidize on the surface anymore. [Answer] Higher rotational velocity, less land, and strategically placed land. <https://en.wikipedia.org/wiki/Roaring_Forties> > > The Roaring Forties are strong westerly winds found in the Southern Hemisphere, generally between the latitudes of 40°S and 50°S.[1] The strong west-to-east air currents are caused by the combination of air being displaced from the Equator towards the South Pole, the Earth's rotation, and the scarcity of landmasses to serve as windbreaks at those latitudes. > > > This leads to Wellington NZ being the windiest city in the world: <https://www.theguardian.com/cities/2015/oct/15/where-world-windiest-city-spoiler-alert-chicago-wellington> > > Wellington sits on the Cook Strait, a passage between New Zealand’s north and south islands. The winds of the Roaring Forties, which spin uninterrupted from South America thousands of miles to the west, are funnelled into this 14-mile-wide gap, creating a “river of wind” that rocks the boats in the harbour day and night at an average of 16.6mph. > > > [Answer] I am structural engineer. With the International Building Code wind speeds can be predicted based on location, topographic features, etc. Generally, if the landscape is flatter, it will be windier. The wide open ocean sees stronger winds than we do on land. Coastal areas experience stronger winds than inland areas. Also, flat grasslands or deserts have stronger winds than areas with trees and hills. Thus, one option to look at is creating fewer obstructions to wind, such as fewer and lower mountains. Another option that might be worth considering is the thickness of the atmosphere. Upper atmosphere winds are much higher than surface winds. You might try modeling your world with a thinner atmosphere. [Answer] (This may or may not fit, depending. It depends on if your 'anything that that makes the planet uninhabitable without fancy technology' includes 'things that are already built but that you don't need a techbase to take advantage of'.) There are many factors influencing windspeed. One of them is simply temperature gradients - think e.g. sea breezes and land breezes, caused by different rates of temperature change between land and sea. Well, how can we have higher temperature gradients than usual? Here's one possibility: the planet had a [solar shade](https://en.wikipedia.org/wiki/Space_sunshade) or solar concentrator installed, once upon a time, that is now partially degraded, so some areas are getting 'normal' solar flux, whereas others are getting artificially high (or low) amounts of sunlight. (It doesn't actually need to be degraded. It could be simply e.g. that it was programmed to send more light to agricultural areas and solar farms, with feedback from the ground to avoid destructive longer-term consequences, and now is no longer receiving feedback from the ground.) That is, roughly speaking, you have a single large Fresnel lens, or more realistically a bunch of smaller ones, sitting near the L1 point, maybe with a few LCD panels for attitude control (as the L1 point is unstable). Rotate each just fast enough to keep the entire thing in tension. (Be aware that a sunshade doesn't last forever without replenishment. If you want it to be independent of civilization you'd probably want e.g. an automated facility on the moon or somesuch that occasionally launches replacements. I haven't worked through the numbers but even 'just' an asteroid in a stable orbit would likely have the mass to keep it going for a good long time.) [Answer] Ice age and vast tundra areas. You need two things as has already been mentioned. Temperature differential and flat land that will not obstruct wind flow. Simple modeling will reveal seasonality of the winds. Arranging mountainous areas directionality with the winds will help. Also make areas that are not affected interesting potentially valuable. On mobile now sorry for the brevity. ]
[Question] [ There's a growing number of people who have telekinesis of different strengths, maybe as high as 1% of the population. Many sports are collapsing into squabbles among players and spectators over alleged subtle telekinetic cheating - nudging a ball, interfering with equipment, or just a little extra power at a critical moment. What can we do? We can't let these cheaters ruin sport! EDIT: to clarify, no simple, reliable detection of telekinesis exists at this point in the story, hence why there are disputes. Reliable detection would settle any argument, as would blatant visible cheating, but when the leading cyclist slides on a wet road, was it because someone nudged his wheel? [Answer] You have two options: 1. Develop a telekinesis detecting test, so that you can screen the telekinetic out of the venues where the sport event take place, and keep them at a distance where they cannot interfere. This would mean that having telekinetic capability would be an impeding factor for playing sports, similar to what for example a health condition can be 2. Integrate telekinesis in the rule of the game. Why is it legal to have Michael Jordan or Shaquille O'Neal in the team, ensuring superiority to their team, and not a telekinetic athlete? Philip Dick in many of his stories has psi and anti-psi, acting against each other. Same can be in this case. A telekinetic can try (and maybe succeed) at countering the power of their opponent, in the same way a defender can try to stop the dribbling of CR9. That's part of the game. In 2) spectators being telekinetic is a relative issue: as long as they are on both sides, they can try to fight each other, sort of like what they do today already when singing chores. That would put some reality into the "public is the 12th men on the field" (12th for football, other sports have other number) [Answer] If this is a natural world, there would be no sport that does not already include the influence of TK within the game. We wouldn't be looking at how to fit TK into a game, but should be thinking of how sport would exist in the ambient background of TK. If there were a significant change in the availability or power of TK, there would be disruptions within the sport. We see the same thing today, not with TK, but with steroid medication and tests for gender specific hormones. It echos in the discussions over trans-women participating in women's sports. There is a disruption -- in pharmacology or social values -- and the disruption impacts sport and games. In your world, sports would have included TK. If the stakes for success are low, the rules would be "soft" and not need to be enforced. In our world, who really cares if one kid is getting growth hormones for some condition, and it helps them hit better? In a sand-lot baseball game, no one cares. The sport is about the play, the team, and friendly competition. Teams are fluid. If one player is noticeably better, he will be switched over time between teams. In your world, TK abilities would just be one more aspect of athletics. A player might be a slow runner, have bad eyesight, but help the team with TK abilities. Another play may be weak at TK, but runs faster. The mix of abilities would naturally work together on a team. If the stakes are high, the player's play probably wouldn't be changed, but the influence of the crowd, the promoters, the advertisers, and the gamblers would be valid points of concern. High stakes means many more stake holders. We have the same problems now, with players being bribed to shave points, horse trainers drugging racehorses, and athletes (and athletic sponsors) trying to game the drug-testing procedures. With high stakes, it is a story of influence and corruption, just as it is today. TK is one more pathway for corruption to be applied, but it isn't a new problem. It is only a new vector. If this is critical to your story, I would suggest simply adding a line that everyone played fair. If you want to drive it into the plot, it would be the same sort of investigation and exposure plot you would write about this works, with some TK bling. [Answer] ### A world-building answer: In theory, I have the same problem in my universe. I call it "magic", but it's effectively telekinesis (but with the addition that you make "spells" that can be used even by non-magic-users). I pretty much ignore sports since they are not relevant to my story. Also, as noted, your problem goes well beyond sports as magic/telekinesis opens up all sorts of interesting (read: scary) possibilities with respect to crime. Again, this isn't really relevant to my story, but that doesn't mean I haven't considered it. I take a three-fold approach: * Prevention: In my world, there are various branches of "magic", one of which offers the possibility of suppressing others' abilities. In your case, this would mean a person or device capable of suppressing use of telekinesis either by a particular individual or within a venue. * Detection: Like you, only a modest number of people in my world can use "magic". A much larger number, however, can sense when magic is being used. For your case, simply employ these people as referees. Use of telekinesis results in an automatic "foul" (or at least a do-over if you can't tell which side is using it). * Deterrence: My world is really harsh on misuse of "magic". As in, criminal use warrants immediate revocation of someone's ability to use "magic"... on the "got off easy" end. More serious offenses are capital crimes (i.e. death penalty). The [Red Queen](https://en.wikipedia.org/wiki/Queen_of_Hearts_(Alice%27s_Adventures_in_Wonderland)) approach is probably a little severe for your scenario, but perhaps a player caught using telekinesis is immediately black-listed from athletics, or a fan black-listed from attending any sporting events in person (much like how casinos in the real world black-list suspected cheaters). I call this a "world-building approach" because at least two of these imply altering the rules of your world. [Answer] The ball itself is a trap. Depending on the telekinetic this may not work, but the general assumption is that to move something with your mind you need to be aware of what you are moving. If you can't see something because its inside a safe would you still be able to move it? If not then there's your trap. Have your ball be a bell. Cheaters that try to nudge the ball into another direction will have to focus on the outer layer of the ball. Inside is actually another sphere that sounds any irregularities. If it moves midair it makes a sound. Although bells are noisy anyway, so I suggest they put motion detectors inside the ball and around the stadium to prevent any cheater from winning large amounts of money in tournaments. Lowkey tournaments may not have enough on the line to care. If that doesn't work, anti-telekinetic ball it is... If the telekinetic can sense the objects around them, including the mechanism and would be able to prevent it from going off, well you're pretty much screwed. There would have to be some material that can't be manipulated or the military would have to study and develop a counter, but I doubt tournaments would bother buying a state of the art anti-telekinetic ball on the off chance someone is cheating. [Answer] Suppose the ability would always be known before the sporter starts his/her career, no cheats. Suppose the ability is socially acceptable, and society has found ways to turn it into something useful. Any sports performed by non-telekinetic people could be affected (see comment above) so the only solution for that would be: two separate worlds. Telekinetic sports and non-telekinetic sports have nothing in common. People with telekinesis abilities will not take part in classic sports at all. Telekinesis Olympics Telekinetic sports events could be spectacular and very funny. Only some telekinetic sports are competitive: the Telekinesis Olympics is primarily intended to show off your skills. Some telekinetic sports have important cultural and artistic aspects. Spectators People with telekinetic ability should not be welcome at any sports events bearing competition. This is really a pitfall, it requires personal checkups for attendants. [Answer] Most likely, we'd see pogroms and a race to develop tests along with mandatory testing. Sudden sharp increases in the rate of murders, especially those associated with gambling. Would probably also see the careers of the most talented players ruined with gossip that they were secret telekinetics, even if they passed such tests. The only people still outside of camps who test positive for telekinesis will be a select few who have "agreed" to work with the government. I can almost read the "telekinetic pervert remote-fondled me" headlines now. Sports will be the least of it. [Answer] ## Taking the posed question literally. Can't detect, deter or prevent and it pretty much ruins sports as is. Solution - sports as is is dead/dying unless you can figure out how to detect, deter, or prevent. You could try non-magical, non-extra sensory measures such as high speed cameras, combined with computer based review looking for interference and assign suitable penalties when interference detected - but the issue of fan interference may make that untenable as well, i.e., fans could interfere in-order to be detected and sabotage play by triggering the penalty. Detection would have to include not just detection, but identification of the person interfering so that the penalty could be applied to the source of the problem, e.g., ejection from game, banned from ballpark, etc. If gambling on sports is legal, penalties would have to have further real-world consequences sufficient to deter offenders - but unless you can identify the person causing the interference, detecting the fact of interference is simply not sufficient to prevent ruining the game. [Answer] Half-answer/idea for detection anyway: Every telekinetic individual has to stop breathing momentarily while they focus on moving an object telekinetically. Trying to do it while breathing fluidly is just like sneezing with your eyes open - it can't be done. So tiny, paper thin sensors are placed on the chest of individuals, much the way super sensitive electronic tattoos can 'read your mind' (read the narrator of your mind as you send small signals to the vocal chords even when not activating them fully to speak) - these devices can single out diaphragm tightening for telekinesis specifically, not just someone holding their breath in anticipation as a shot is heading towards the hoop/net/goal. If you need there to not be any detection, I second the answers that say you simply can't stop the cheaters / it's solely honor based. [Answer] Advanced Physics + Incredible Creepiness. Everybody is filmed nearly all the time and an incredible AI analyzes the footage for instances of statistically unlikely events, or SUEs. It's just a matter of waiting for the AI to locate telekinetic individuals. When an SUE occurs during a game, the roster is crosschecked to see which individuals have the highest rate of SUEs and voila! [Answer] ## Cheating Players aren't the problem! Any well-coordinated supporters' club will synchronise their telekinesis to deflect the ball to benefit their team. Unless supporters are banned from the area, there are no rules in sport that can deal with this. Even supporters overlooking the pitch from a nearby hotel will be able to affect the result. [Answer] Technology Think "Hawkeye" or "VAR" - technologies currently used in sport. These would be developed further to a more advanced level. AI and computers might not be able to detect actual telekinesis, but they can detect a subtle but unlikely swerve of the ball, or unusually increasing or decreasing momentum. Unfortunately it's difficult to know who to punish. You can't simply punish the team who benefits, because then they will start using telekinesis against themselves in order to draw a punishment on their opponents. e.g. a striker is about to score a goal, and a defender will "help" him score, which the AI will detect and the goal will be disallowed. [Answer] Another approach, the telekinetic becomes part of the game, whoever can "push" the ball wins the contest, whether by mind or by arm, and a strong TK talent might be critical for a winning team ]
[Question] [ I imagined the scenario for a story where the USSR still forms and will later fight in a Cold War with the USA. However, I am imagining a scenario where the tsar escapes, goes with some loyal followers to another location (on Asian continent or other location) and is able to establish a great power in the region, still being somewhat relevant on the global stage. Is there anyway for this scenario to realistically happen (tsar and members of his family escapes, form great power somewhere without it instantly being crushed by United States or USSR, etc.)? [Answer] If the Russian Empire in an alternate history has colonies in North America, such as Alaska and surrounding parts of Canada, the tsarist forces could retreat to Russian North America just like the Portuguese government retreated to Brazil when Napoleon invaded Portugal. Here we would have a kind of cold war between USSR and RENA (Russian Empire of North America). The RENA would have massive propaganda efforts onto the mainland, trying to undermine the communist government's authority over the Russian people in any way possible. It would be a propoganda of conservative, traditional, orthodox values. Things would get interesting as that would force the communist government actually have positive changes in the mainland to legitimize their rule over the Russian people there. They would be forced by circumstances to make a better life for the people in order to prove that they are the more worthy rival government, instead of just acting without regard of the best interests of the people, knowing that any misstep would be used by the tsarist government as a propaganda opportunity. That would improve the quality of life of people in the USSR, and also preserve 19th century Russian culture in the RENA. The political history of the USSR would be completely different. The RENA would also become a great power faster because they would get a lot of refugees from the mainland escaping the Soviets. Cossacks, Old Believers, merchants, peasants, scientists, engineers, philosophers, and any other people who fled the Soviet Union to United States, France, Germany, and elsewhere would most likely have instead gone to the RENA, boosting it's population. In particular scientists and engineers would have been a great benefit for that growing new country, allowing them to have at least an initial technological advantage over the Soviet Union. A possibility would be of a five way cold war between USSR, RENA, USA, Nazi Germany, and Japanese Empire. Now with more players on the scene you no longer have a winner takes all scenario. Instead you have more healthy competition, and none of the individual players is strong enough to defeat the rest. [Answer] Escape execution - yes. Form an independent country - highly unlikely From Nicolas II abdication on 2(15).03.1917 to his execution on 17.07.1918 there were multiple opportunities to spirit the former tsar away from his detention, especially early on. For example, in March-April 1917 there was an active plan to let Nicolas leave for England, however George V, after some hesitation, rejected the idea. At any rate, before Nicolas and his family were sent to exile in August 1917, a determined plan to let him escape the captivity had a very high chance of success. A very good question is what to do next. In late 1917, Russian Monarchy had no base of power. There was no safe heaven for Nicolas II. He could reach England, and British authorities would be unlikely to deport him back, but former tsar would have no power there. He could (at least formally) lead the [White movement](https://en.wikipedia.org/wiki/White_movement) in Russian civil war. But then it is very unlikely that the two sides could fight to a standstill. White movement could prevail, and then there would be no Soviet Union, or it could be defeated, and then Nicolas would be another exiled monarch at best. There is just no middle ground - no natural defensible border in Russia where Bolsheviks and Tsarists reach some kind of balance. Retreating to distant areas like Far East, Caucasus or Crimea could only postpone the inevitable. [Answer] Getting out of St Petersburg in a hurry, as the masses are starting to revolt, you don't have many choices. At this point in history it's at least a week to get Asia. (I'd love to see them in China or Vietnam or something, but I just can't see them making the trek across Siberia). They'd need somewhere really close, and if you're escaping by boat or road, there's a nearby state, about 100km away, which doesn't make it into the USSR. Finland's independence is closely tied into the 1917 Russian revolution, the abdication of "Grand Prince of Finland" Tsar Nicholas the 2nd led to its independence. > > After the February Revolution and the abdication of Tsar Nicholas II, Grand Prince of Finland, on 2 March (15 March N.S.) 1917, the personal union between Russia and Finland lost its legal base – at least according to the view in Helsinki. There were negotiations between the Russian Provisional Government and Finnish authorities. > > > ([Source](https://en.wikipedia.org/wiki/Finnish_Declaration_of_Independence)) I don't know what those negotiations were, but that could've been cover for "New Identity please". It's a short boat journey (~100km) from the Winter Palace in St Petersburg to Finland. Some dedicated loyalists could smuggle you out easily. They've had a [tricky relationship](https://en.wikipedia.org/wiki/Finland%E2%80%93Russia_relations) since. I can't see them forming a direct power, but they could form a secret government in exile, serviced by loyalists, waiting for the right moment to reveal themselves. Or they could rename themselves, disguise their policies, and run for government in the new country. [Answer] Forming your own Great Power is hard work, unless you're Giuseppe Garibaldi, and frankly if the Tsar could pull that off he probably wouldn't have lost his first Great Power. Far better to steal one... or perhaps salvage one. Enter China. In 1916 the last Chinese Emperor died and the country descended into a mess of feuding warlords, all of them keen on gaining some advantage over their rivals. It wouldn't take much to convince one of the Nationalist warlords to take on an advisor who knew the vicious wiles of those fiendish revolutionaries... and as every evil vizier knows, the line between "warlord's trusted advisor" and "warlord" is razor-thin. Now of course, the Nationalists eventually lost the fight for mainland China and fled to Taiwan, but it needn't have been so. If they had managed the fortunes of war better, they could have conceivably have come out on top, and by a very strange quirk of fate, Nicholas Romanov could've led a resurgent, capitalistic China into the world stage during the Cold War. The real problem, as noted in the beginning, is explaining how a leader with the ruthless cunning and drive to see this campaign through, one who could beat Mao Zedong in a winner-take-all contest for China and steer his adopted country against his homeland, could've mismanaged his first realm so badly that it collapsed out from under him. [Answer] ## Maximum awryness: Rise of Siberian Russia 1. Actual historical context: * The Unsung [Revolution of February](https://en.wikipedia.org/wiki/February_Revolution) which Took Place in March: The Russian Empire entered willingly in the First World War, with all classes supporting what was perceived as an opportunity to strengthen the international prestige of the [Rodina](https://en.wiktionary.org/wiki/%D1%80%D0%BE%D0%B4%D0%B8%D0%BD%D0%B0#Russian). Sadly, the Russian war effort did not prosper. The towering stupidity of the Russian high command, notably of the doomed [General Samsonov](https://en.wikipedia.org/wiki/Alexander_Samsonov) and the clueless [General Rennenkampf](https://en.wikipedia.org/wiki/Paul_von_Rennenkampf) led to the disaster of the [Second Battle of Tannenberg](https://en.wikipedia.org/wiki/Battle_of_Tannenberg), where Russia lost almost 200,000 men against less than 15,000 German casualties. (The First Battle of Tannenberg happened half a millenium earlier; in that battle the Teutonic knights lost.) By 1915, the Russian forces were in full strategic retreat, [losing Poland](https://en.wikipedia.org/wiki/Great_Retreat_(Russian)) and Galicia, again with disproportionate casualties. In the summer of 1915, Tsar Nicholas II assumed direct personal command of the army, leaving the governing of the empire in the hands of his loving wife, [Alexandra](https://en.wikipedia.org/wiki/Alexandra_Feodorovna_(Alix_of_Hesse)), who at that time was besotted with the pseudo-mystical [Grigori Rasputin](https://en.wikipedia.org/wiki/Grigori_Rasputin), he whom Boney M famously called "Russia's greatest love machine". By 1916, the situation went from terrible to horrible. On the front, the [Brusilov Offensive](https://en.wikipedia.org/wiki/Brusilov_Offensive) advanced 60 kilometers in four months, at the cost of one million men. (As always, the Russians were experts at solving all military problems by using up expendable muzhiks.) On the home front, Rasputin was [assassinated by a group of high noblemen](https://en.wikipedia.org/wiki/Grigori_Rasputin#Death) led by [Prince Yusupov](https://en.wikipedia.org/wiki/Felix_Yusupov); but the erratic leadership of Empress Alexandra devastated the economy, bringing Russia on the brink of famine; the most ingenious idea of conscripting the Muslim subjects of the empire to fight a deadly war in faraway Europe fired up the [Basmachi insurrection](https://en.wikipedia.org/wiki/Basmachi_movement). Early 1917 did not see any improvement. "In the seventeen months of the 'Tsarina's rule', from September 1915 to February 1917, Russia had four Prime Ministers, five Ministers of the Interior, three Foreign Ministers, three War Ministers, three Ministers of Transport and four Ministers of Agriculture. This "ministerial leapfrog", as it came to be known, not only removed competent men from power, but also disorganized the work of government since no one remained long enough in office to master their responsibilities." (Orlando Figes, A People's Tragedy, 2008, quoted by Wikipedia.) The people of [Petrograd](https://en.wikipedia.org/wiki/Saint_Petersburg) (= Sankt Peterburg, Saint Petersburg, the capital city of the Empire) had had enough. Sporadic strikes began on what the Russians called 18 February and everybody else called 3 March. By 10 March (25 February for the Russians, who were behind the times as usual), the city was in full revolt. The Duma, which was what passed for an Imperial Parliament, saw no way out but to issue a Manifesto requesting the Tsar to abolish absolute monarchy and grant a Constitution. Several Princes affixed their signature on the treasonous Manifesto. On 16 March 1917, Nicholas II, Tsar of All the Russias, abdicated in favor of his brother, [Grand Duke Michael](https://en.wikipedia.org/wiki/Grand_Duke_Michael_Alexandrovich_of_Russia), who promptly declined the crown. (This didn't save him. The Bolsheviks killed him one year later.) The country fell into the hands of the hastily assembled [Provisional Goverment](https://en.wikipedia.org/wiki/Russian_Provisional_Government) whose only vision was to run around like a headless chicken trying to find out [What Was to Be Done](https://en.wikipedia.org/wiki/What_Is_to_Be_Done%3F_(novel)). * Vladimir Ilyich "[Lenin](https://en.wikipedia.org/wiki/Vladimir_Lenin)" Ulyanov, the greatest agent provocateur of all times: Meanwhile, the Germans, exalted by what they perceived as the imminent collapse of Russia, decided to give it push. An officer of the German General Staff went to Switzerland and contacted Vladimir Ilyich Ulianov, aka Lenin, the head of the rabidly extremist [Bolshevik](https://en.wikipedia.org/wiki/Bolsheviks) faction of the [Russian Social Democratic Labor Party](https://en.wikipedia.org/wiki/Russian_Social_Democratic_Labour_Party) and offered him [transportation to Petrograd](https://en.wikipedia.org/wiki/Sealed_train). Lenin jumped at the occasion, and arrived at Petrograd's [Finland Station](https://en.wikipedia.org/wiki/Finland_Station) in April 2017. In six short months, Lenin's inflamatory speeches and the violent tactics of his fanatical supporters destroyed Russia's political system, what was left of it, and rendered the Provisional Government powerless to run the country. * The [Great October Socialist Revolution](https://en.wikipedia.org/wiki/October_Revolution) which Took Place in November: On 23 October 1917 (10 October in Russia), the Central Committe of the Bolshevik Party adopted a resolution calling for immediate armed uprising. On 7 November (25 October in Russia), the Bolshevik Military-Revolutionary Committe of Petrograd lauched an armed uprising against the [Kerensky Government](https://en.wikipedia.org/wiki/Directorate_(Russia)). The [Winter Palace](https://en.wikipedia.org/wiki/Winter_Palace), the main seat of the Russian Government, did not resist. (The 140 female soldiers of the [Women's Battalion](https://en.wikipedia.org/wiki/Women%27s_Battalion) who were supposed to defend it did not feel like confronting 40,000 furious Bolsheviks.) 2. Initial points of departure: * The former Tsar is still at Tsarskoye Selo: In real history, [Alexander Kerensky](https://en.wikipedia.org/wiki/Alexander_Kerensky), head of the Russian Directory (the interim government tasked with running the country while the [Constituent Assembly](https://en.wikipedia.org/wiki/Russian_Constituent_Assembly) assembled a Constitution for the newly proclaimed republic) escaped the Winter Palace and fled to [Pskov](https://en.wikipedia.org/wiki/Pskov), where he assembled an army an [attempted to retake Petrograd](https://en.wikipedia.org/wiki/Kerensky%E2%80%93Krasnov_uprising). In real history, the Imperial Family had been relocated to [Tobolsk](https://en.wikipedia.org/wiki/Tobolsk), east of the Urals, in Western Siberia. But in our changed timeline, the Tsar had refused to leave his residence at Tsarskoye Selo (= Imperial Village in English), and happily for him, Kerensky's troops did indeed manage to take [Tsarskoye Selo](https://en.wikipedia.org/wiki/Tsarskoye_Selo). * The [Junker Mutiny](https://en.wikipedia.org/wiki/Junker_mutiny) proves to be more efficient than in real history: In real history, the mutiny of the cadets of the military schools in Petrograd was defeated before it began: one of the leaders of the mutiny managed to be arrested while carrying the plans for the uprising. In the new timeline, Aleksandr Arnoldovich Bruderer evades arrest, and the Junker Mutiny succeeds in its initial plan of seizing the telephone exchange and some key fortresses in Petrograd. * Kerensky's troops, with the Imperial Family, join with the Junker cadets and retreat in order to Pskov, where they make contact with the forces of General [Nikolay Yudenich](https://en.wikipedia.org/wiki/Nikolai_Yudenich). * In real history, Yudenich fled to Finland, and did not return to the Russian Civil War until 1919. In the new timeline, Yudenich joins his meager force with the motley men of Kerensky, takes command and leads an organized retreat through Minsk to Kiev. 3. A slightly different [Russian Civil War](https://en.wikipedia.org/wiki/Russian_Civil_War): * By December 1917, the situation in Russia is almost the same as in real history, with the difference that Yudenich, Kerensky and the Imperial Family are in Kiev, where they have a tenuous relationship with the [Ukrainian Central Rada](https://en.wikipedia.org/wiki/Central_Council_of_Ukraine), which was hesitating between collaboration with the Bolsheviks and moving towards independence. * Seeing how the wind was blowing, Yudenich, Kerensky and the Imperial Family, protected by the Cadets and whetever Loyalist forces they had assembled, move South-East towards [Rostov-on-Don](https://en.wikipedia.org/wiki/Rostov-on-Don), which was firmly held by the [Volunteer Army](https://en.wikipedia.org/wiki/Volunteer_Army) led by [Lavr Kornilov](https://en.wikipedia.org/wiki/Lavr_Kornilov). The long retreat has finally come to an end, and the Imperial Family is safe. * Events follow now real history: Kornilov dies in his attempt to take Ekaterinodar; the Volunteer Army executes the fabled [Ice March](https://en.wikipedia.org/wiki/Ice_March) (this time with the official head of government and the Imperial Family in tow); [Anton Denikin](https://en.wikipedia.org/wiki/Anton_Denikin) takes command of the [White Forces](https://en.wikipedia.org/wiki/White_Army) in Southern Russia. The White Army launches the [Kuban Offensive](https://en.wikipedia.org/wiki/Kuban_Offensive), taking control of South-Eastern Ukraine, Crimea, and the entire [Kuban](https://en.wikipedia.org/wiki/Kuban_People%27s_Republic) region between the Black Sea and the Caspian. * As in real history, the Bolsheviks sign the shameful [Treaty of Brest-Litovsk](https://en.wikipedia.org/wiki/Treaty_of_Brest-Litovsk), ignominiously exiting the First World War and leaving their allies (notably Romania, sob, sob) hanging in the wind. * Events continue along the real historical path (maybe with the presence of the Imperial Family leading to a less atrocious [white terror](https://en.wikipedia.org/wiki/White_Terror_(Russia)) in Denikin's area of control) until late 1918. 4. The decisive points of departure: * In real history, the Eastern and Western parts of the putative Russian Republic fighting against the Bolsheviks did not speak to one another, did not co-ordinate with one another and generally behaved as if the other part did not exist. Moreover, they had only the most tenuous relationship with the [Allied intervention forces](https://en.wikipedia.org/wiki/Allied_intervention_in_the_Russian_Civil_War) which were supposed to help them. * In the new timeline, Denikin, as soon as the Kuban offensive gave him control of the entire strip of land between the Black Sea and the Caspian north of the Caucasus, names Yudenich as head of the Co-ordination Service, and he establishes a joint planning committee aiming to harmonize the movements of the Western White Forces in South Russia with the mightier Eastern White Forces in Siberia. * As a result, instead of launching two separate offensives in 1919, the White Forces coordinate and Denikin's [Advance on Moscow](https://en.wikipedia.org/wiki/Advance_on_Moscow_(1919)) is timed to coincide with [Alexander Kokchak](https://en.wikipedia.org/wiki/Alexander_Kolchak)'s general offensive. * As in real history, [Leon Trotsky](https://en.wikipedia.org/wiki/Leon_Trotsky) attempts to dupe [Nestor Makhno](https://en.wikipedia.org/wiki/Nestor_Makhno)'s anarchist [Black Army](https://en.wikipedia.org/wiki/Revolutionary_Insurrectionary_Army_of_Ukraine), which was wrecking havoc in Southern Ukraine, into attacking Denikin's forces in the rear; but this time Denikin is alert and obtains support from the Polish and Romanian intervention forces, which keep the anarchists occupied and take [Odessa](https://en.wikipedia.org/wiki/Odessa). * By judiciously timing its offensive to coincide with the great eastwards push of the Eastern White Forces, the Southern White Forces avoid [defeat at Orel](https://en.wikipedia.org/wiki/Orel%E2%80%93Kursk_operation) and succeed in establishing contact with Kolchak's forces in [Samara](https://en.wikipedia.org/wiki/Samara) and [Ufa](https://en.wikipedia.org/wiki/Ufa). * In the summer of 1919, the White Army holds a continuous piece of territory stretching from Crimea and Rostov-on-Don (on the northern shore of the Sea of Azov) through [Tsaritsyn](https://en.wikipedia.org/wiki/Volgograd)¹ (later named Stalingrad, now Volgograd) to Samara and Ufa and onwards to the entire Siberia. (The White forces really held Siberia through out the Civil War, and they really took Tsaritsyn, Samara and Ufa from time to time.) ¹) They really [took Tsaritsyn](https://en.wikipedia.org/wiki/Battle_of_Tsaritsyn), with the help of the berskerker attack led by Major [Ewen Cameron Bruce](https://en.wikipedia.org/wiki/Ewen_Cameron_Bruce), who was more or less the entire British intervention forces on the Southern Front. * Seeing that some sort of half-victory was at hand, Kolchack (or rather Kerensky, acting on behalf of Kolchack) manages to convince the the [Supreme Allied Council](https://en.wikipedia.org/wiki/Supreme_War_Council) to withdraw its insistence that Russia renounce forever the restoration of monarchy, with the intention to capitalise on the Russian muzhik's love for the Father Tsar. * The Supreme Allied Council reluctantly agrees to let a future Russian Constituent Assembly decide between republic and monarchy, and steps up the supply of materiel, both through the American-held Vladivostok and the Trans-Siberian railway, and through the much closer at hand Black Sea and Rostov-on-Don. * Helpfully, [Mikhail Tukhachevsky](https://en.wikipedia.org/wiki/Mikhail_Tukhachevsky) is killed during his attempt to retake Ufa for the Bolsheviks in the autumn of 1919. With him, the Bolsheviks lose their only competent military commander. 5. Conclusion. * In 1920, with their economy in tatters, with the [approaching specter of famine](https://en.wikipedia.org/wiki/Russian_famine_of_1921%E2%80%9322) profiling on the horizon, with their opponents enjoying a steady flow of weapons, ammunition and supplies, the Bolsheviks make overtures for peace. Trotsky and [Bukharin](https://en.wikipedia.org/wiki/Nikolai_Bukharin) lead the Soviet delegation, with the negotiations taking place in Tsaritsyn. The Whites agree to evacuate Crimea, giving the Reds access to the [warm water port](https://en.wikipedia.org/wiki/Port#warm_water_port) of [Sevastopol](https://en.wikipedia.org/wiki/Sevastopol); they keep Rostov-on-Don. The frontier is established from Roston-on-Don along the Don up to [Kalach-na-Donu](https://en.wikipedia.org/wiki/Kalach-na-Donu), then accross to the Volga at Tsaritsyn, up the Volga through Saratov and Samara, then east along the [Kama](https://en.wikipedia.org/wiki/Kama_(river)) to the confluence with the [Belaya](https://en.wikipedia.org/wiki/Belaya_(Kama)), along the Belaya to its source, then along the crest of the [Ural Mountains](https://en.wikipedia.org/wiki/Ural_Mountains) to the [Kara Sea](https://en.wikipedia.org/wiki/Kara_Sea). The Reds keep [Novaya Zemlya](https://en.wikipedia.org/wiki/Novaya_Zemlya), the Whites keep [Vaygach Island](https://en.wikipedia.org/wiki/Vaygach_Island). * In 1921, the Constituent Assembly of Siberian Russia, sitting in [Yekaterinburg](https://en.wikipedia.org/wiki/Yekaterinburg), proclaims the country a constitutional monarchy, with Nicholas II assuming the title of Emperor of Siberia and retaining considerable executive powers. * Basically, the Russian Empire splits into its European part and its Asiatic part. The Soviet Union retains 80% of the Empire's population and economy, while the new Empire of Siberia retains a lot of underpopulated territory, rich in minerals and timber. [Answer] The Russo/Chinese Border, but Probably Nowhere The problem I see is not one of escape, there are plenty of dice rolls and coin flips during a revolution, and it wouldn't take much for the Tzar to have successfully bolted or one of the older children to escape. (I don't think a younger kid would have the gravitas you want, if just Anastasia escapes she's a figurehead sure, but unlikely to be a real ruler-in-exile imo.) The tricky part is "Where do they go where they can still be a Power?" My first thought is somewhere in the Russian far east, where they might gather loyalist forces and form a new power base. Somewhere along the Sino/Russian border for instance. They go there, a less-immediately-vengeful Red Russia doesn't follow or makes a truce, and between Imperial Loyalists and encroaching into Chinese territory made easy pickings by the chinese civil war they could establish a decent manpower base. You could maybe get local (mongolian/chinese) support just by being a less-corrupt government than the warlords and providing local security. Though you would have to do some pretty slick deals with the Chinese nationalists and/or Communists to pull it off. So you can conceivably make them a Nation. Probably not a Great Power Worthy Nation however. Except that such a power, positioned to strike on behalf of the Nazis, could have war-changing implications. The Nazis were kept out of Moscow by troops transferred from the far east. Throw an actively hostile force in the far east and the USSR can't pull the men, Moscow falls, and maybe the USSR with it. Of course the problem there is I don't see for an instant the Lenin or Stalin allowing part of Russia be independent of the USSR, especially with the Czar or his kin at its head. If you want to keep all of Russia Soviet however I just don't see a place for them. The various chinese warlords/governments wouldn't take them in on their own when the russians could easily go after them. The western nations and colonies might take them in (I seem to recall talks about the Brits wanting to take the Czar and have him live in the Netherlands or somehwere) but that's a government-in-exile and not a real "Fielding an Army" Power for WWII. I guess you could always have the Czar/his kin escape in such a manner, then when the nazis take over strike some sort of deal. Hitler was a racist and a moron, but possessed a certain low cunning politically. Perhaps a malleable son or daughter of the Czar could have been used as a Slavic figurehead promised to be returned to the Russian people, and thereby foment internal problems for the USSR. The Czar was fairly well liked (though his wife was hated) and it might have helped the Axis cause, but that doesn't seem to be exactly what you're after. As a world leader the Czar just wasn't liked enough, and didn't have the influence, to just vanish and set up as head of a new country somewhere else. King of england? Sure he might become head of South Africa or Canada or Australia in a pinch, but Czar of all the Russians? No. Not without some alt-history Russian overseas territories or a bit of handwavium anyway. [Answer] There is a novel by Vasily Aksenov called "The Island of Crimea" describing a scenario that may be useful for you. In that novel's world Crimea is an island, not a peninsula, and it gives refuge to the White movement after they lose the Civil War, with some aid from the British Navy. It becomes something akin to what Taiwan is to China. While in the novel Nicholas did not escape there, it certainly won't be impossible for that to happen. Even though it won't be a Great Power comparable to USA/USSR, it could become quite wealthy and developed, and then, who knows, maybe snatch more land at the coast of the Black Sea, e.g. taking part in the partition of the Ottoman Empire. And even if you don't want to alter the geography that much, altering history so there was a channel dug between Crimea and the mainland is reasonably plausible. ]
[Question] [ Aliens arrive today (2020) and are not completely peaceful. The aliens destroy all Earth satellites instantly. So that means a lot of the more advanced military technology like guided missiles and drones are off, right? I'm only interested in what Earth military systems are disabled and disrupted by this attack. I'm sure if you can still work a weapon with 80% efficiency it's better than not having it. I'm just focusing on knowing what will fail. so please please please lets not get off topic and insist that humans should surrender because FTL travel=insta win or that they can weaponize asteroids or the other stuff. What military technologies will be mostly disabled by the loss of satellites and to what degree? This is mostly focused on the biggest militaries out there for obvious reasons, like the USA, Russia, China, Germany, Japan, Britain, and France. I don't mean to disrespect the smaller countries or anything, actually they will play a part but this isn't the place. I just want to focus on the biggest countries with the most advanced military. [Answer] GPS and similar systems (Russian GLONASS, Chinese BeiDou, for example) are the first thing that comes to mind. Modern militaries rely heavily on extremely accurate positional systems for navigation, coordination, and intelligence gathering. The loss of GPS would be crippling for aircraft and ships, and extremely inconvenient for land forces. Drones and missiles may or may not be effected, since some use satellite navigation and communication and some do not. *How could they adapt?* Land forces would be able to adapt most quickly, given that static maps, roads, rails, and landmarks are still there. The US Navy and Airforce, I'm told, still teach traditional navigation techniques so after some brushing up they could probably be operational again soon. I'd assume every major power does also, or would quickly learn. General communications would be lost too. Terrestrial communications are dominant across domestic territory, ranging from optical fiber to point-to-point microwave transceivers. Across borders, in the air, and in the ocean, however, satellite is very important for maintaining communications. The ability for military forces to coordinate in real time would be devastated. *How could they adapt?* During WWII, the allies maintained a network of radio repeater stations. Artillery units would send target information and wind conditions out over radio, the message would be repeated from station to station all the way back to England or the USA, mechanical computers would calculate the firing angles, and those angles would be sent back along the network. The turn-around time was only a few minutes. Today, there's several independent networks of terrestrial radio repeaters run by various private and government organizations. These networks are usually used during disaster relief operations, but they could be co-opted for warfare easily enough. Modern consumer radio transceiver technology allows a hobbyist to reach clear across the Atlantic on a good day. Nuclear early-warning systems would be effectively neutered. Due to the uncertain circumstances they were designed for, intercontinental nuclear missiles don't rely on outside systems for anything at all. They navigate by dead reckoning. ICBM detection systems, on the other hand, are bolstered by satellite monitoring to detect launches ASAP and ready defenses. There are other detection systems, but satellites give the earliest warning. With the loss of those satellites, everyone would have much less time defend against a nuclear ICBM and it'd be an ideal opportunity for one nation to strike another, or even these aliens launching one of these missiles in order to sow discord among the world powers and prevent them from cooperating. *How could they adapt?* Not many options here. Observer posts all over the world near (known) launch sites, equipped with long-range radios would be the only option I can think of and it's a real stretch. This could well be the worst consequence of losing satellites. [Answer] > > Aliens take out our satellites > > > > > Soviets take out our satellites > > > The military is already expecting a sophisticated adversary to do that pretty much as their opening gambit. Most likely in the year or three before a conflict, the adversary will “get busy” and * Launch a bunch of hunter-killer satellites, able to thrust over to the enemy satellite, grapple and de-orbit (if they're nice). * Or, they will have tuned up their ASAT capability; AEGIS destroyers can already do this, and the Chinese have shot one down also. * Or if they're not nice, destroy everything at a particular orbit altitude, by causing [Kessler Syndrome](https://en.m.wikipedia.org/wiki/Kessler_syndrome). This is the least sophisticated option; no precision tracking/seeking is needed; nothing but a box of nails and a hand grenade. Any country capable of orbiting something can do that. * Jamming satellites. Different technologies in space mean different frequencies they are working on. These can be clouded by noise on that frequency, while not interfering with your own. * Hacking satellites can be even more productive. The ability to take over the enemies information and possibly launch systems can change the course of military material, personnel and rockets. In addition, they might launch or give orders to launch them at valid targets, only to take them over en route. * A midsize military such as Japan, Australia or India does not own their GPS or other satellite services. They rely on other countries' satellites, and they expect their access to be turned off when things get hot. (The US would surely continue to support Japan, but may have to turn off public GPS to deny it to enemies). So the military is equipped and drills all the time to function in a no-satellite world. Because it's pretty much expected that'll happen. They're ready for aliens to do it, because they’re ready for North Korea to do it. [Answer] * Supposedly the military trains to cope with [GPS jamming](https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Artificial_sources_of_interference) just as they train to cope with NBC conditions, or blizzards. Just how well trained they are is a good question. * The loss of GPS will also disrupt the civilian rear area supplies. What good is a howitzer that can fire without GPS if the shells are stuck in the traffic jam? * The military has become used to GPS-guided or GPS-aided weapons which hit their target or very close to it. Before that it took more shots to do the job. Instead of a single fighter lofting a [JDAM](https://en.wikipedia.org/wiki/Joint_Direct_Attack_Munition#JDAM_Extended_Range) from beyond close-range air defense, they had to send an entire squadron. But there are are [fewer planes today](https://www.airforcemag.com/PDF/MagazineArchive/Magazine%20Documents/2011/May%202011/0511facts_figs.pdf) than during the cold war. ]
[Question] [ Goblins in my setting are around four feet tall, with batlike ears, a keen sense of smell, and lithe, dexterous bodies. They are omnivores, eating slightly more meat than the average human, and their skin is tinted yellow-green or olive. What sort of environment would best suit them? [Answer] 1. Lithe, dexterous, good hearing, short. I would place them somewhere that vision is less important and hearing more. I would place them someplace with many obstacles to straight movement where their dexterity can serve in good stead. A forest or "jungle" would work. If you have a D&D type underworld that would work. A more exotic environment like the stone needles in [this answer](https://worldbuilding.stackexchange.com/questions/81077/a-realistic-option-for-enclosing-a-geographic-area/81086#81086) would work. Tall grasslands might be a good option too, especially if goblins are nocturnal. 2. Goblins are social. Small omnivores can eat a lot of carrion, like skunks or opossums. There is not much need for them to be super quick or social. If you want them quick then they could catch their food and semi-arboreal hunters in an environment with lots of obstacles could catch birds. Sociality does not help with that kind of hunting. Social omnivores could mean pack hunters. So: goblins can be pack hunters living in a visually and spatially obstructed / dark environment. [Answer] A forest environment would be quite good, dense undergrowth blocks line of sight meaning that vision is less important than some other senses. Keen hearing and a good sense of smell would help,them detect prey and predators without seeing them. Their lithe dexterous nature would help them climb like monkeys or lemurs and skin tone camouflage against some leaves. [Answer] I would assume that the goblins of your setting are sapient tool users. It means, essentially, that they could adapt to any environment, just as humans. Most of the factors you describe - height, sense of smell, hearing, skin color - do not strike me as essential. What seems to be important are their dietary requirements. If they need more meat in their ration then human, it means they would develop animal husbandry over farming. Farming won't give them the essential nutrients, so it seems the Neolithic revolution won't happen to them - or it would look differently, if it did. So I would expect fishing villages, migratory hunting and herding communities and, possibly, mountain villages with transhumance herding. It is hard to say anything else about them, because we don't know much about your world - what is the climate and continents, what is the population pressure of your goblins, are there other sapient races that compete for resources and land. If there are other races with farming and bigger population, you can expect your goblins to be pushed to less hospitable areas. [Answer] The homonin species that most closely resembles that was homo floresensis, which lived on a heavily-forested island. The goblins might have started off looking like the real-world “hobbits.” They’re that size and have large ears because they hide a lot; they might hunt fast animals by ambushing, or perhaps they’re not at the top of the food chain. Flores had giant komodo dragons. The sense of smell might be useful for scavengers and the coloration would be good forest camouflage. [Answer] Your Goblins are quite similar to Goblins from Goblin Slayer (great anime with a rough start), in GS they tend to live in forests with nearby mountains and human settlements, they make burrows by digging or use old mines/forts. Just from the fact that yours are green or yellow tinted you can place them in forests, prairies for the green ones because that would help them camouflage, and the yellow ones can be from more arid places (even though the best camouflage color for desert is pink). Since you haven't said which era your world is I assume that is a medieval one, so I would place them nearby human settlements which they would approach to steal supplies/food, which would make villagers ask adventurers to slay them, which as an story hook for a MC works great specially if you make goblins quite easy to kill if they are lonely but big bastards if they are in a group on a cave. [Answer] To add to the other great ideas with a keen sense of smell they also could live in underground tunnels and come only up to hunt. So underground tunnels under a forest in the forest itself they got the advantage because of their colour and because they don't need to see well and they can hide in their tunnels there they have the advantage over any enemy that depends on sight. [Answer] I'd say large cave systems. Being short and dextrous makes it easier to move around small tunnels and tight entrances. As most animals who thrive underground, they rely mostly on their hearing and smell than their sight. Light skin, greyish or greenish, also makes sense for environments with little or no light. As for their diet, it really depends on what else is available in your world. But assuming they are somewhat smart, they could easily get outside (maybe at night, when hearing is enhanced and sight is less important) to hunt or fish. In general, any biome that doesn't let you rely on sight (lots of obstacles, or lack of light) would work. ]
[Question] [ As the title says, you know stuff like minotaur, lycanth or werewolf, cat or dog folk, etc especially for the female specimens. I want to know what happen if quadrupedal mammals which usually have their teats around their stomach evolve normally to become bipedal, will their teats change place to around their chest or still develop around their stomach? And I heard carrying baby is the reason primate breast developed around chest (correct me if I'm wrong) so just consider in both situation if this quadruped mammals carrying their baby (or whatever real reason that make primate developed their teats there) and if they don't, what the musculature especially their breast or anatomy would look like in both situation, considering most of them have multiple breast or nipple. Reason why I ask this? It can help me see how their muscle look especially for female and help me to imagine what attire and armor can be look like for them. Also just in case I consider human chimera type like centaur, harpy and other mythological or fantasy creature that basically human body (especially that have human breast already) strap with animal part is not part of this question. It mostly for pure mammalian animal maybe exception if they only have human face and the rest still animal, like sphinx for example, with other matching criteria I describe, if there such a creature. [Answer] Mammals (males as well as females) have what are called "mammary lines": [![enter image description here](https://i.stack.imgur.com/gQiBK.jpg)](https://i.stack.imgur.com/gQiBK.jpg) This is a bilateral structure that rules where mammary tissue can develop. Apes (among whom humans) generally have two and those towards the cephalic end of the line. Some people have three or four. Many quadrupeds have breast tissue at the caudal end of the lines --- a cow's udder being the best known. Not all quadrupeds are built alike. Dogs, wolves, cats, pigs and so forth have many operational breasts --- eight or ten, and all up and down the thorax and abdomen: [![enter image description here](https://i.stack.imgur.com/OVN5g.jpg)](https://i.stack.imgur.com/OVN5g.jpg) Note that bears have four breasts and are already in the "human positions": [![enter image description here](https://i.stack.imgur.com/qiMp7.jpg)](https://i.stack.imgur.com/qiMp7.jpg) Same goes for elephants, who have two: [![enter image description here](https://i.stack.imgur.com/rF9LB.jpg)](https://i.stack.imgur.com/rF9LB.jpg) My answer would be: # UNLIKELY Carrying babies around is not likely to be the cause of breast migration. Newborns already have the ability, if left to their own devices, to crawl and find mama's breasts. Most primate babies are pretty good at gripping and hanging on to mama as she moves around. Evolution isn't reactionary. The animals that evolution happens to react to the vagaries of its change. *Edit: (With Elemtilas' permission via JBH). IMil points out that if we all came from one source animal, then nipples most certainly migrated as today they are on different locations for different mammals and have different counts. However, from an ultra-simplistic point of view, all mammals basically began as quadrapeds where babies sat on the ground to reach over to, or up to, the teats. Yes, bipeds must lift the child to make up the difference (or lie down). But since they're capable of doing so, and perfectly willing to do so, there's not been evolutionary pressure for the nipple to move for bipeds.* However, if 100 million years from now they were to migrate, they'd probably migrate to our ankles or hips as those would be far more convenient than the stomach, which would get in the way of playing video games. --- Since your basic question boils down to a fantasy race, I'd suggest that *it's your world, you make up the rules. But do consider the following: Breast tissue in dog / wolf / cat / elephant / cow folk will not "migrate" upon them taking a bipedal stance. Their breasts will continue to be in their ancestral locations most likely. * "Breasts" in the human sense of the word probably will not evolve in these kinds of races. Wolffolk with two D-cup human-like breasts exist solely to attract and titillate the desires of human males. While I'm not complaining, the arrangement makes them more "relatable", like [this example](https://www.deviantart.com/zinzoa/art/Werewolf-girl-569482414) of a typical wifewolf vs this possibly more likely but [less human-relatable example](https://www.deviantart.com/tchaikovsky2/art/Vita-tayari-623295214). * Clothing: why would beastfolk need clothing at all? Clothing has nothing to do with species or race; it is a social construct (for the most part) and I would suggest considering it as such for your own beastfolk. If your werewolves are furry, they won't need clothing at all, because they can already pant to reduce body temperature and they've already got fur to keep warm. If they are not furry, they may only need clothing in the depths of winter. * Armour: here you'll need to consider their body shape. If your werewolves are more canine in shape, then you'll want to consider armor to conform to a canine body shape. If they are basically human body shaped but with beasty features, then you'll be looking at armour fitted to a human body plan. If your females retain canine breast morphology (eight all along the chest and abdomen; flat except when lactating) then male and female armour will be essentially identical. If you choose to go the human male lust enhancing route, then you'll need armour fit for a Wagnerian Valkyrie. [Answer] Sure, it's called [convergent evolution](https://en.wikipedia.org/wiki/Convergent_evolution). > > analogous traits arise when different species live in similar ways > and/or a similar environment, and so face the same environmental > factors > > > Natural selection expressed through (first) survival, and then reproductive success, ensures the continuation in the species of those traits which enable the organism to reproduce. If it became an advantageous survival trait, then yes, the breasts could migrate (so, for example they could run without udders being ruptured by collision with their knees. - But that's an oversimplification - in practice the upright walking and the breast migration would occur in a not-independent way, over considerable time. That being said, there's an alternative: [Atavism](https://en.wikipedia.org/wiki/Atavism), a phylogenic trait - ie. one which has occurred in the past-history of the organism's ancestry, but the environment has resulted in the gene being switched-off - is of necessity switched-on again. You need to ask yourself "what is deep in this organism's past that can be switched-on again? That could result in the breast's being developed here (ie. wherever your story demands). This all being said - it's all up-to-you as the writer to make a decision as to how much to give explanations. Sometimes the idea that the reader comes up with their own explanation is useful. See: [Death of the Author](https://en.wikipedia.org/wiki/The_Death_of_the_Author). (That is also an oversimplification). [Answer] Now that you mention it, there might be an issue with that. If they were of any decent height relative to the babies, then they'd have to carry them to suckle. With mammaries in the abdomen like most mammals, the mothers would have to be cradling the babies right against their lady parts, which is hardly a good idea - mainly, either could get an infection of some sort. Also, what if they were menstruating? Additionally, it's much easier to carry things against your chest than at your hips. Perhaps you're right and it would be beneficial for the mammaries to migrate upwards. [Answer] I think SealBoi hit the right note, in that the question you should be asking is "how do my critters nurse their young?". If they always lay down to let their babies suckle, there is no reason for "migration" or other changes to occur. If they need to suckle while standing on two legs, that is a good reason to transition to a more human-like anatomy. The reason I'm posting an answer instead of a comment is to address one of your other questions; what would these critters' attire look like? While answering your question as stated is relevant, something else to keep in mind is that most non-lactating mammals are flat-chested. Human mammaries, which are always prominent, are the exception rather than the rule¹. (One of my favorite examples is from "Uhurah's Song", wherein one of the felinod aliens asks a human female what happened to her young, having mistakenly assumed said human to be lactating.) As such, unless you adopt this trait also², your female attire is likely to be divided into "normal", and one or more varieties to accommodate gravidity and/or lactation. (On which note, do keep in mind that humans have special "maternity" clothing.) (¹ ...and before you mention cows, make sure to find a picture of a non-dairy cow. Dairy cows are always lactating, not to mention the effects of selective breeding for milk production.) (² ...which would be strictly for fanservice. Literally. To wit, I remember reading a claim somewhere that the only reason human females always have pronounced mammaries is because of their "effect" on human males, specifically, as an incentive for "dad" to stick around. By corollary, if your critters' females are typically single moms, there would be no reason for this trait to develop.) ]
[Question] [ i.e left-to-right, right-to-left, top-to-bottom etc. My guesses so far : * righty/lefty person, * material on which writing is done, * tools by which writing is done etc. But I'm not able to convince myself on any particular point. [Answer] It's important to note that the incidence of left-handedness in middle-eastern countries is roughly the same as those in western countries, and if anything, left-handedness is even more discouraged in those countries because of a cultural belief that left hands are less clean (or intended for less clean work) than right hands. From that perspective, the incidence of left or right handedness doesn't seem to be a compelling consideration for the direction of text. That said, there is an argument that can be found on the internet that states that when Hebrew was first written, it was written in stone and clay, by right handed people. The left hand was used to hold the chisel, the right hand the hammer, so writing right to left allowed right handed people to see into the space they were writing. The argument goes further to say that most middle eastern countries also write right to left because of the influence of the Hebrews in their early histories, but I've never found concrete evidence of this. That said, it does go to medium and 'handedness' being considered in concert as an influence on script direction. The outlier here is Asian writing styles, that were traditionally vertical. This may have more to do with the design of the script itself. The design of the characters (especially the compound characters) lend themselves to vertical interpretation, so character design may well be a consideration in the orientation of the text as if the 'pen' tends to end on a downward stroke instead of a lateral one, then the text is probably more easily written vertically as it reduces the distance the hand must travel between characters. The outlier of the outliers is of course Hangul, which is the Korean form of writing and was designed by a select body of linguists appointed by the ruler of the Korean peninsula around the 14th century. This really is a nerd's writing system as it was designed from the ground up by their own (I say this as a computational linguist by trade). While it was traditionally (and is still for artistic purposes) written vertically in similar form to Chinese, today it's largely written horizontally in Western form and a close examination of the characters will tell you that such a change in orientation isn't that difficult for the characters as they lend themselves to being written quickly in either orientation. Hangul Rocks (but I digress). The key point here is that left or right handedness is ONLY a consideration in conjunction with the medium and writing tools as a whole; what lends itself to convenient writing with hammer and chisel is very different to what lends itself to convenient writing with ink. Also, in terms of horizontal or vertical orientation, the style of the characters will be highly influential. Of course, the one consideration which we've overlooked in this dissertation, and arguably it's the most important, is convention. If the people around you are writing left to right, top to bottom, you're more likely to write that way yourself, even if your script is different, and especially if it's the same, just in a different language. Why? Because writing is only done by people who want to be understood by others. There's little point having a writing system if people can't understand it, and even less point if you're not leaving words for others of different languages to one day interpret into their own. Writing is about the efficient transfer of knowledge between individuals, cultures, and eons. In other words, people WANT their writings to be read. Just like it's believed that many Arabic countries write from right to left because the Hebrews did it first, and that Hangul started out vertical (like China) but is now often horizontal (like Europe, USA, etc.) one can expect new scripts will follow whatever is the dominant convention surrounding them. If on the other hand writing is new to your world, then pick whatever is the most convenient; Horizontal orientation will be decided by a combination of which hand is used most commonly and what media, tools and techniques are used. The choice to go vertical will be decided more by the nature of the characters used. The important thing to remember out of all of this is that people who write want their work to be read. As such, they'll pick the orientation that is most likely to ensure that objective is met. [Answer] I am a left-handed person; so although I learned to write from left-to-right and top-to-bottom, that is a terrible way to write if you use ink that can be smudged; because my hand travels over just-written text before the ink has dried. As a child, I tried various correctives. For a few years I rotated my paper 90 degrees clockwise (so the top pointed to my right) and I could write my lines vertically and progress to the left (down the page). I taught myself to write the characters sideways, obviously, so when the page was read normally the characters appeared normally. Now I still write similar to that, with the page upright, my hand curled over above the text. Also, I need to be slightly careful writing on the board in class, to not smudge the text to the left of what I am writing. In grade school (ages 6-12) my teacher tried to force me to write right-handed. That didn't last a day, my father (also a lefty) took care of that (I don't know what he told them). In general, for a left-handed inventor using any smudgeable medium (ink, chalk, paint), the most natural directions would be right-to-left, bottom to top, so the hand was always in an unmarked part of the page. [Answer] ## What if it's by accident? Writing direction was not always carved in stone, so to say. For example: * Ancient Egyptian inscriptions are written indifferently left-to-right or right-to-left. To know which is which, look for the hieroglyphs in the shape of animals, and note which way they face. Ancient Egyptians even liked symmetry, so that inscriptions on the left and right sides of a monument, for example, are written in opposing directions. * The oldest Greek inscriptions were written [boustrophedon](https://en.wikipedia.org/wiki/Boustrophedon) "like the oxen when ploughing", one line left-to-right then the next right-to-left and so on. * In the ancient Near and Middle East, [cuneiform script](https://en.wikipedia.org/wiki/Cuneiform) (used to write Sumerian, Hittite and a host of Semitic languages, notably Akkadian) was initially written top-to-bottom right-to-left, but switched to left-to-right top-to-bottom (rotating all characters 90° counter-clockwise!) around the middle of the 3rd millennium BCE. * [Phoenician script](https://en.wikipedia.org/wiki/Phoenician_alphabet) (from where the Hebrew, Arabic, Greek, Latin and Cyrillic alphabets come) was written right-to-left but also sometimes boustrophedon (see above). * [Etruscan script](https://en.wikipedia.org/wiki/Old_Italic_script#Etruscan_alphabet), the immediate predecessor of the Latin alphabet we all love, was written left-to-right, or right-to-left, or boustrophedon. * The oldest Latin inscription ever found, the [Praenestine fibula](https://en.wikipedia.org/wiki/Praeneste_fibula), is written right-to-left... [![The Praeneste fibula](https://upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Praeneste_fibula.JPG/640px-Praeneste_fibula.JPG)](https://commons.wikimedia.org/wiki/File:Praeneste_fibula.JPG) The Praeneste fibula, carrying oldest Latin inscription ever found (7th century BCE): MANIOS MED FHEFHAKED NVMASIOI (Manius made me for Numerius), written right-to-left. Photograph by [Pax:Vobiscum](https://commons.wikimedia.org/wiki/User:Pax:Vobiscum), available on Wikimedia under the CC BY-SA 3.0 license. ]
[Question] [ Certain fantasy creatures are extremely sensitive to concentrated UV light. eg modern vampires. They either slowly or rapidly burn up in-front of you when exposed to direct sunlight or modern high techy UV-lightsources. I am trying to figure out if these creatures sensitivity to UV could be used as a method of passively identifying them, in situations where they are not exposed or burning. Essentially, when not exposed to direct sunlight, do vampire bodies absorb/reflect UV differently to a human; which could then be detectable by modern science? If my near-future military designed something similar to our current-day night vision goggles, they could then be adjusted to work for vampires. If I hand certain characters [specialist goggles](http://blog.phillips-safety.com/what-are-forensic-glasses/) capable of viewing the UV spectrum, would these vampires jump out of the crowds as either noticeably more reflective bright points or absorptive blackholes? Without actually exposing the vampires to an active [Blacklight](https://en.wikipedia.org/wiki/Blacklight). Or would they look the same as a typical human until exposed and then they would light up on the thermal infra-red spectrum? [![enter image description here](https://i.stack.imgur.com/uNixP.jpg)](https://i.stack.imgur.com/uNixP.jpg) Image of a human artist with phosphorescent bodypaint under a blacklight...She is not a vampire. [image source](http://billytzphotography.com/black-light-project) DISCLAIMER: * I am aware that the original Dracula and other vampires were not hurt by sunlight and that this is a modern interpretation of the legend. * I'm not after the sparkly-kind vampires...unless I should be. --- EDIT: * I know Vampires can have many weaknesses that I can utilize. For example, my vampiric creatures are not harmed by garlic or the sight of crucifixes but can be deterred by UV light and water, that for some asinine reason my characters may have decided needs to be blessed. They are not dead per se but I have trouble picking them up on the IR scanners as they have a very low resting body temp. IR may be useful for identifying cooler vampires in large crowds of normal humans, however IR is not helpful in picking out Vampires in more isolated situations where they may be creeping up to attack your outpost etc. They will more than likely light up on the IR spectrum when they are fully exposed to light. Hence, I am focussing my question on just how their body reacts to UV light. * I'm not too worried how they react to massive amount of direct sunlight. They combust and burn. The speed of the combustion has yet to be determined as I need to figure out the actual mechanism causing it. Do they absorb or reflect or do their bodies react no differently when not exposed to excess UV. What would that look like in a topical exposure situation (no excess UV). To avoid answers focussing on the wrong end of the reaction, I am focussing my question on how they would react in passive, non deadly exposure situations. * I am focussing on their bodies reaction and not so much on the technology itself to see them. I can handwave the tech around how the body mechanism works, but I won't turn away any pointers. I mentioned the tech ability to see them, as that is my reason for this question. To figure out if they will be pretty bright lights, depressing black death-shadows or worse, show no difference at all! * I am hoping to identify them from a distance without actually having to come into contact with them. I'm not scared or anything. HQ is the one insisting on this simple safety precaution. [Answer] So we can actually use science to help us out with this fantasy concept, believe it or not. This is what I mean: vamipirism was initially inspired by a variety of illnesses, most notably a genetic blood disease (erythropoietic protoporphyria). Individuals with this disease are sensitive to light because MORE UV is being absorbed in to the skin, hence causing more damage. This is due to the accumulation of protoporphyrin in the skin, so what you can do is have vampires possess an accumulation of a certain molecule in the skin that absorbs UV light rather than refracts it. [Answer] Vampires are fictional creatures. In the stories I have read some are sensitive to garlic, some to holy water (and were mocked by non christian influenced vampires for this), some to light, some to silver, some to wooden stakes. To cut it short: it is your story, you are free to set up any reaction to UV light that suits your plot needs. By the way, being non living creatures they would be "cold", so IR vision would not spot them from the background as it does with living beings. [Answer] If homo inimicus vampirus were real, and were so radically sensitive to UV light as proposed, and if that were similar to the issues porphyriacs suffer due to excessive epidermal protoporphyrin, they would indeed appear significantly darker than homo sapiens when seen in UV light: moreover, you'd not need a strong UV source to show this effect assuming reasonable active signal processing in your nightstalker-vision goggles. More than likely there would be a visible mottling similar to advanced age sunspots, or possibly to the pattern of veins in the skin, showing areas of greater protoporphyrin density, which would also be visibly different than homo sapiens. But bear in mind human skin already absorbs a whacking lot of UV, hence both the dark look of the model in the photo you posted and our need for sunscreen. They also wouldn't necessarily be instantly aware of UV impingement if the level of UV light were low - IRL I knew a porpheriac who had a severe breakdown due to excessive light and temperature exposure, and it was not by any means an instant affair: she was exposed, and over several days was more exposed (all her choices) and during this became more and more irrational and irritable, resulting in a fugue state and obsessive behaviour, which then gave way to high risk / gambling behaviours, the consequences of which precipitated a divorce, and not long after this a complete breakdown and suicide. She experienced pain, fear, anger and severe irritability starting some hours after the exposure began. You could choose to parse that in your fiction as giving rise to a supernaturally strong fight-or-flight cortisol / adrenaline response to major UV exposure, with pain/fear/anger, and that might add far more verisimilitude than the typical "burst into magical flames and ash out instantly" treatment. [Answer] Seeing as the UV-light is something that is invisible to our naked eye and can't be seen because we haven't adapted to it, using goggles that pick it up would be a good idea. (erythropoietic protoporphyria) is a disease as said above, that causes our skin to absorb more UV-light than usual, if this is the case the goggles would not be able to pick up UV-light on vampires because they would be absorbing it more. If you see a square that is red, that's because it absorbed every color except red in the visible part of the light's spectrum. I would imagine that when your character looks through these glasses ordinary people would be visible but vampires would very little, or completely invisible. Basically your character suspects someone is a vampire in a crowd of people.They put on the goggles, and if they can see everyone in that crowd except the person they are suspecting, that person is indeed a vampire. (I'm not an expert and any experts are free to correct me if I'm wrong.) Keep in mind if you add science to your story, you would have to explain how different stages of darkness affect your vampires. For example if they are in shade, but the place is still visible to the naked eye, light is reflected to that position (it's just less intense). That means that the UV-light is reflected there aswell. Will this make your vampires weaker, or will they burn but at a slower pace? If you're making the case that UV-light hurts your vampires this is something you should keep in mind. The only place were they would be safe is in a place with no or very little contact with sunlight. ]
[Question] [ Orbital denial is like area denial but applied to the entire orbit of a planet or even a star. I don't remember where I first heard the term but I know Max Brooks uses it in [World War Z](https://en.wikipedia.org/wiki/World_War_Z) and suggests that the controlled detonation of a single space station could be sufficient to shut down operations in Low Earth Orbit indefinitely. So how would that work? The question is twofold: 1. How much material would need to be flying around that it couldn't be mapped and avoided with modern imaging and radar techniques? 2. How big would the fragments need to be for modern space stations, capsules, and satellites to be at risk at standard orbital velocities? For those unfamiliar with the parlance [area denial](https://en.wikipedia.org/wiki/Area_denial_weapon) is a strategy used in ground combat in which a section of the battlefield, or even of a whole country, is rendered inaccessible by virtue of containing a high density of "passive" weaponry (i.e. weapons that don't require an operator). Weapons used can be as simple as stakes in the ground or as complex as motion trigger machine guns but have traditionally been things that soldiers or vehicles "trip" by either standing on them or driving over them. The example case for orbital denial would use the same principle of a dumb object you have to run into but in this case it's debris and the kinetic energies involved are much greater. [Answer] Ah, [Kessler syndrome](https://en.wikipedia.org/wiki/Kessler_syndrome). Always a favorite when it comes to orbital disasters. I wrote about [a similar situation](https://worldbuilding.stackexchange.com/a/76322/627), where it becomes impossible for humans to safely reach Earth orbit, based on data from space agencies. I used the equation ([Eq. 2](http://webpages.charter.net/dkessler/files/DerCollisionProb.pdf)): $$N=vAn\Delta t$$ where $N$ is the number of collisions over a period of time, $A$ is the area of the spaceship or space station, $v$ is the relative velocity of the ship and the piece of debris, and $\Delta t$ is the period of time over which the encounters occur. Let's say $A=500\text{ m}^2$ (a large-ish ship/small-ish space station), $\Delta t=5600\text{ s}$ (the approximate period of the ISS), and $v=15\text{ km/s}$, twice the orbital speed of the ISS (remember, this is the relative velocity, so each object could be moving at that speed but in opposite directions). If we set $N=1$ (one collision per orbit), we find a number density of $$n=\frac{N}{vA\Delta t}=\frac{1}{15000\cdot500\cdot5600}=2.38 \times10^{-11}\text{ m}^{-3}$$ Consider, though, a ring centered at the ISS's orbital radius (about $400\text{ km}$). If the ring has a radius of $10\text{ km}$ - enough to hit such a target, even with a non-circular orbit - then its volume is approximately $\sim10^{13}\text{ m}^3$. This means we'd need about 200 objects with random, uncontrollable paths in that area alone to make a collision likely. And that's just one orbital area! That said, you'd need the number to be even higher, for several reasons: * 200 objects is certainly enough to track. The US alone [tracks almost 18,000 pieces](https://en.wikipedia.org/wiki/Space_debris); 200 would be easy. * The objects would have to be big to cause any damage to a properly protected spacecraft - and the bigger the object, the easier it is to monitor it. * Even if you cover this toroidal region, any ship can simply choose a different orbit (within reason). So maybe you can shut down a couple of orbital lanes, but there are plenty more available. So, orbital denial isn't easy to manufacture in such a way that it could affect an entire planet. It's quite hard. [Answer] A single station blowing up would create a big headache for those planning orbital insertions but there isn't enough material in the ISS or anything reasonable to build and launch to cover more than a small area. For one thing, you would have to shred it into confetti to cover a wide area. Good luck with that. In most explosions, most of the material would be in rather large pieces since an explosion is an expanding gas or plasma in a container that prevents it from getting out. The container generally fails along its weak points and the gas or plasma spends most of its force getting out through that opening. The only way to get confetti is for the explosion to be big enough and spread through the container evenly enough that it, essentially, breaks out of the container everywhere. Having said that, orbital denial is easy. Have 3 or more satellites (for coverage) that launch missiles (or guided crow bars) down at anything trying to launch from the earth. It takes a lot of fuel to launch and most launching rockets tend to be big and slow. They are heavy enough that the will likely not be maneuverable enough to do much dodging. It would be like shooting clay pigeons. A launch would be like yelling "pull". This is why there are so many treaties about limiting weapons in space. It isn't because that they are afraid that we would kill each other there. It is because they can be used to deny all access to space. [Answer] I think it matters greatly if this is an accident, an improvised attack or a deliberate attack. In a worst case scenario of a deliberate attack it should be easily possible. For instance: Using a large launch vehicle (such as a Saturn V for arguments sake), launch the payload into earth orbit and send it to the moon. Loop around the moon and return in a figure of eight entering a retrograde orbit around earth at the required altitude. At this point release the payload via a small explosive charge. The payload being 40 tons of 1g steel ball bearings. 40 million of those in and around the intended orbit should effectively destroy anything in that orbit. I doubt that such small objects could easily be tracked and I’m sure that one impact would be sufficient to cause catastrophic damage due to the energy involved – especially in a retrograde orbit. If the a space shuttle widow was damaged by the impact of a paint flake, a 1g ball bearing should be big enough and have sufficient energy to make a good sized hole in anything likely to be in orbit. [Answer] It's surprisingly easy. Just throw sand. Kinetic energy being proportional to $v^2$ comes in surprisingly handy for this sort of thing. Let's say we want 1m^2 coverage per ISS-like orbit. (That is, one collision on average per orbit per 1mx1m area.) Using the same equation as [@ShadoCat](https://worldbuilding.stackexchange.com/users/33610/shadocat), i.e. $$N=vAn\Delta t$$ $\Delta t=5600\text{ s}$ (period of the ISS), and $v=15\text{ km/s}$ (relative orbital speed, considering that the orbits are retrograde to each other). So then, the density is $$n=\frac{N}{vA\Delta t}=\frac{1}{15 \frac{km}{s}\cdot1 m^2\cdot5600s}=1.19 \times10^{-8}\text{ m}^{-3}$$ If we consider the volume of a spherical shell around the Earth from, say, 350 - 450 km, this works out to a volume of roughly $2\cdot10^{17}m^3$. So we'd need $~2.4\cdot10^{9}$ particles. This sounds like a lot, but is surprisingly small. A small grain of sand might be 10mg - in which case you'd need to lift ~24000kg to orbit. A single delta IV heavy could do that. 10mg particles at 15 km/s aren't immediately catastrophic by any means (~1100J, about on par with a pistol shot), but they aren't to be sneezed at either. (Antennas, altitude jets, solar panels, etc are likely to take damage relatively rapidly. Ditto spacewalks / etc.) This likely is an 'orbital denial' only in terms of 'no-one can stick around, or have solar panels out, etc'. A single launch through wouldn't be nearly as likely to be affected. Note that this isn't likely to clog up the skies forever. Reentry times are going to be in months, not years. (Reentry from 450km is a lot longer than from 350, note.) (Debris caused by said cloud, however...) (In practice, you'd do this with a number of smaller launches. It takes a lot to change orbital planes). (I'm also glossing over a number of things here - the orbital velocity here isn't actually double on average, (although it's biased that way) etc. But this is largely counteracted by my calculations here assuming that you need to cover the globe, whereas in practice you only need to cover much less.) [Quick calculation](https://www.wolframalpha.com/input/?i=10mg+%284%2F3++pi++%28450km%29%5E3+-+4%2F3++pi++%28350km%29%5E3%29+%2F+%2815+km%2Fs++5600s+*+1m%5E2%29). [Inspiration](https://www.space.com/20925-space-station-bullet-hole-photo.html). --- Now, as to if you could do this with a controlled detonation of a single space station? No. The orbital mechanics don't allow it. It'd have to be retrograde to start, and even then the spread wouldn't be sufficient. Although if you could... the ISS is somewhere around half a million kg, or ~500cm^2 coverage all on its own. ]
[Question] [ This is The Sahara Project my grandfather made up with me: On the western African coast and its surroundings, where the rocky Sahara desert lies, great fields of solar panels will be placed; they will generate a giant amount of energy. But instead of just providing plain electricity, the energy will be used to do this: * boil seawater to get water and salt * put iodide into the salt and sell it * using the electricity it will break down water to oxygen and hydrogen * export hydrogen as a fuel for cars, etc. * sell some of the oxygen to whoever wants it, and release the rest into the atmosphere This project has many advantages: * efficiency: hydrogen is easy to store; electricity is not * logistics: hydrogen can be transported easily * burning hydrogen doesn't produce CO₂ or other bad things, just water * some of the distilled water can be distributed over Africa * this would create a bunch of working spaces — a few smart people would be needed, and a lot of any people (even those that can't read and write) to clean and maintain the panels and other utilities * this would upgrade Africa's political situation — they would have a giant source of money (mostly funded by other states) * no emissions This project would have to have a giant investigation at the start, but would promote the world's economics. Water, fuel, salt and electricity prices would drop, and Russia and the Arabic states would go down. The institution would return to the countries in a couple of years. Also, this project would make a great jump in technology. New technologies would have to be developed, like in America's moon project - when they started the project, it seemed impossible. But they did it, and some of the inventions from then are used today. Is such a giant project achievable? I know it will never happen in reality, but that's because if the political situation, but I'm asking about the technical side of this. Is this technically possible? [Answer] It is possible and you can start small and scale as you go. Panels might not be best for that scale, but have the advantage of being self contained and someday might be cheap. Hydrogen is not easy to store: it is dangerous and difficult. You might make methane instead, using atmospheric carbon as the source. You big problem is: why isn’t it profitable now? logistics. You produce power have industry that needs power over there. How do you get materials in and products out? Focusing on ambient source materials, you still have to worry about shipping. How do you get the concentrated power out of the desert and in the hands of customers? Where do the workers live? How do they eat and otherwise have a life? So besides understanding the amortization of solar equipment cost against cost of power produced, you have to realize that if the panels are cheap and available then factories will install them right next to the need, and won’t need to buy from you. The shipping of any goods produced will need to be with the price. BTW, I have a 10 kW solar array at home. I run the air conditioner in the Texas sun and still have surplus to sell. [Answer] Go through a few items on your list...but this isn't as feasible as you are hoping. One item that you've badly missed is weather and maintenance. Desert winds bring sand which has the tendancy to get into every nook and cranny you could imagine (even into your cranny's nook?). Maintaining these solar panels and keeping the dust and sand off them is a rather large ongoing expense you will need to consider. > > effectivity: hydrogen is easy to store; electricity is not > > > Very not true. Hydrogen will need to be compressed if you want to store much (liquid?) and tends to be explosive. There is much danger here. > > logistics: hydrogen can be transported easily > > > Electricity transports pretty readily, hydrogen transport now requires moving physical hydrogen (which can be explosive). Seems better to move the electricity to where it's needed, then use it to create the hydrogen there. > > this would upgrade Africa's political situation — they would have a giant source of money (mostly funded by other states) > > > If history repeats...you'd have warring factions trying to control the new source of money and it'd likely be destroyed in the process. > > no emissions > > > Solar panels are composed of some pretty toxic substances and have limited lifespans. This is what I like to call emission deferral...it's only no emissions because you defer the toxic impact to some future date. [Answer] Your economic problems Most of your exports are hard to export and not very valuable, * Water is dirt cheep, the main cost is moving it * Salt very cheap fairly heavy * Hydrogen is somewhat valuable but dangerous to move (see JDlugosz answer) * Oxygen is also a bit tricky to move, its a corrosive corrosive flammable gas. * Electricity requires you to have electric lines that connect you to a major users, or a ludicrously expensive set of batteries. You are deliberately putting your self in the Sahara a long way from anyone who is would buy any significant quantities of any of these things. At first you would have to build hundreds of miles of powerlines to reach cities large enough to use your power. It is very difficult to maintain power lines over long distances in politically unstable counties (the copper wires are stolen) so even if you built the hundreds of miles of power lines there are a number of African Counties that you would not be able to maintain them in, though some you could. Your shipping costs will probably vastly outweigh the value of your products. Yes this would employ tons of people but then it would probably collapse due to lack of profit. [Answer] The idea is not new. One of these days something might come from such proposals. * [Desertec](http://www.trec-uk.org.uk/) * [Medgrid](https://en.wikipedia.org/wiki/Medgrid) Regarding your specific idea, why separate the purification and electrolysis steps? It might reduce the maintenance of your electrolysis systems, but the power is used less efficiently. Why not use the (purified) sea water for agriculture and sell the electric power? Depending to the size of the project, it might make sense to go to southern Europe instead, like [this one](https://en.wikipedia.org/wiki/PS10_solar_power_plant). There was some political upheaval in recent years, but not nearly as bad as that in Africa. [Answer] There are other things you can do in the Sahara. If you focus on using local materials and keeping costs down then you should... Build solar furnaces to melt the sand into low grade glass. (smelt out oars as well?) build enormous greenhouses that are watered with simple evaporation based systems. Sell dried fruit and veg. ]
[Question] [ So, I'm looking to get one of my characters poisoned. However, if they notice that something's up, the jig's likely up as they'll seek treatment for what happened, so this needs to happen "under their radar" so to speak. Hence, the poison needs to have the following traits: * Delivered by ingestion (in food or drink) -- dosing can be a single dose, or multiple doses over the span of a couple of days provided symptoms do not start until after the dosing is complete. * No strong off taste, odor, or color (mild tastes/odors/colors can easily be disguised/masked by putting it in an appropriate preparation though) * Delayed action (hours to a few days after dosing is complete) so that they don't associate what's happening with their last meal/drink. * No gastrointestinal symptoms once the poison starts to take effect -- again, so they don't associate what's happening with their last meal or drink. * Complete effect of the poison (i.e. total incapacitation) needs to be within an hour, if not within the span of minutes, after symptoms start to manifest. * Needs to be incapacitating for a period of one week minimum, if not fatal. Do any known poisons do this? In particular, I'm concerned about the "no gastrointestinal symptoms" part, as it seems that all the real-world poisons I've researched cause gastrointestinal disturbances when ingested. [Answer] Ricin Famously used in Breaking Bad, I think this is probably the poison you're looking for. > > Delivered by ingestion (in food or drink) > > > According to the [Wikipedia](https://en.wikipedia.org/wiki/Ricin) page, A dose of purified ricin powder the size of a few grains of table salt can kill an adult human. > > No strong off taste, odor, or color > > > If you put 3 grains of table salt on a burger, would you taste it? > > Delayed action (hours to a few days after dosing is complete) > > > From the wiki page, Because the symptoms are caused by failure to make protein, they emerge only after a variable delay from a few hours to a full day after exposure. > > No gastrointestinal symptoms once the poison starts to take effect > > > In the case of a non-fatal overdose, Victims often manifest nausea, diarrhea, fast heart rate, low blood pressure, and seizures persisting for up to a week. In the case of a fatal amount ingested, Ricin causes severe diarrhea, and victims can die of circulatory shock. Diarrhea can be caused by a number of things, such as food poisoning or unsanitary water, so while they may make the link to their last meal, they might not necessarily think it was poisoning. Also of note, ricin is also poisonous when inhaled, so the victim need not ingest it to receive a lethal dose. > > Complete effect of the poison (i.e. total incapacitation) needs to be within an hour, if not within the span of minutes, after symptoms start to manifest. > > > This one, I haven't been able to find information on. My guess is that if you're worried about the victim seeking treatment, it shouldn't be much of an issue - all cures currently in development seem to be experimental, and have not undergone human trials yet. > > Needs to be incapacitating for a period of one week minimum, if not fatal. > > > Again according to the wiki, Death typically occurs within 3–5 days of exposure. For a non-fatal overdose, as stated above, symptoms typically last for up to a week. You can find more info on Ricin [here](http://www.bt.cdc.gov/agent/ricin/facts.asp). EDIT: ~~Another possible poison is Strychnine... I'll try to put together a more thorough answer tomorrow.~~ Strychnine is a really interesting neurotoxin with some pretty brutal symptoms, but they typically occur within 15-60 minutes of ingestion (Source: [CDC](http://www.bt.cdc.gov/agent/strychnine/basics/facts.asp)). [Answer] Low tech: amatoxin found in various poisonous fungi such as the death cap amanatia phalloides and the destroying angel amanatia virosa. It takes five hours to a day before the victim becomes ill by which time the destruction of his liver and kidneys is irreversible. An unpleasantly slow death follows. It does not taste unpleasant and kills many inexperienced and unwise foragers for edible mushrooms each year. The Roman emperor Claudius was probably assassinated this way. Beats me why anyone with enemies would ever eat mushrooms. High tech: a Boron salt (non toxic) followed some hours later by a guided tour around a nuclear facility where the victim and his guide are exposed to a smallish neutron flux. Boron absorbs neutrons and violently fissions. I would guess that the result would be much like polonium poisoning. The guide would not be harmed. Or polonium. Google Alexander Litvinenko for all you need to know. This is real, not fiction. Edit I forgot maybe the nastiest of the lot. monomethyl mercury. A tiny droplet absorbed through the skin will be lethal -- after some months of suffering. (So maybe not fast enough). The assassin's biggest problem is probably avoiding poisoning himself. It soaks through much chemical protective gear as if it was not there. Edit 2. Cholera is not generally considered a poison but an infectious illness can be administered as one. It certainly causes GI upset (!) but might not be associated with a meal if the assassin can make sure nobody else gets infected (or more evilly that a lot of innocents do get infected). Given modern medical intervention it is unlikely to be fatal but certain to incapacitate. Will also trigger a major public health emergency (which may or may not fit with your plot). [Answer] ## Simple time delay If the target takes medication, preferably [hard capsules](https://en.wikipedia.org/wiki/Capsule_(pharmacy)#Two-piece_gel_encapsulation_.28.22hard_capsules.22.29), it makes it really easy. Pick any number (or combination) of fast-acting (or slow, I suppose) poisons, fill a capsule, and place it in their medications/vitamins. Hard capsules will take a few minutes to several hours to digest, and can be made fairly precisely. Replacing the contents of capsules was used in 1982 to carry out the [Chicago Tylenol murders](https://en.wikipedia.org/wiki/Chicago_Tylenol_murders). ## Long-term ingestion In small enough quantities, poisons are undetectable by taste or smell. Toxic metals have the ability to [bioaccumulate](https://en.wikipedia.org/wiki/Bioaccumulation), or build up in the body; lead and mercury are well known, but there are [any number](https://en.wikipedia.org/wiki/Metal_toxicity) of toxic metals. Unlike some poisons, since metals are elements, they can't be destroyed, which means that they can be delivered through smoke (poisoned tobacco or candles), food, liquid, chairs, even soap - anything the victim comes in contact with. Unfortunately (for the poisoner, at least), most symptoms of metal toxicity are recognizable and often treatable before death, meaning that unless you use a really big dose, chances are, your victim is going to live to make it to the hospital. The best option would be to slowly administer small amounts over the period of a few months or weeks, waiting for you victim to begin exhibiting symptoms; early symptoms are usually ignored, but if you know what you're looking for, you can spot them easily. Once the first symptoms occur, follow up with a moderate dose. The larger dose, coupled with the built-up smaller doses, will surely kill your target. ## Radiation Poisons are useful because they are cheap, easy to procure, easy to administer, and at least some of them are hard to trace. However, certain particles are deadly in doses as small as a few atoms - radioactive materials. While some radioactive materials take hours or days to kill someone, once ingested, if you really want to be sure of death, use some polonium. Polonium may be hard to come by, but it is [effective](https://en.wikipedia.org/wiki/Polonium#Well-known_poisoning_cases). With a large enough dose, death would occur within seconds. Followed by the deaths of everyone in the house, block, and possibly city. I would suggest wrapping the dose in a lead sheath and placing that in a capsule. And hire someone else to administer it. ## Death by Boom As long as we're talking about elements, a capsule containing Caesium would be sure to make an impression. Caesium metal reacts violently with water, producing hydrogen gas, then igniting the gas in an explosion. Not only that, but a dose of 4.1 micrograms of Caesium-137 is enough to [kill a dog](https://en.wikipedia.org/wiki/Caesium#Health_and_safety_hazards); a dose of twice that would surely be enough to kill a human, and would be such a small dose that there is no chance it would be detected in food. ## In summary There are a lot of poisons that would fit your requirements, enough that you can choose exactly how you want your victim to die, even down to a precise time. Do you want to be sneaky or bold? Does timing matter enough to be precise to the second, the hour, or the week? Messy, or clean? Quiet, or violent? Fast death, or lingering pain? Undetectable poison, or a brash warning to others? [Answer] Traditionally arsenic was used for many of the reason that you suggest, although arsenic is not a particularly fast acting poison, it has most of the other attributes you want. Arsenic was often administered in food, seems to have little identifying taste and accumulates in the body over a period of time until the victim has ingested enough to become very ill or to die. Since the mechanism of death is interruption of the body's ATP energy cycle, death often occurs due to multiple organ failure, making it very difficult to recover from, although there are treatments that can remediate arsenic toxicity if the ingestion is discovered in time. So don't be afraid to be a bit old fashioned. [Answer] Rat poisons are a good start [Thallium](http://www.compoundchem.com/2015/03/19/thallium/) is one, and was widely used. Depending on dosage Thallium can be either fast or slow acting, potentially taking several weeks from the initial poisoning. There is no known antidote once the poison has been absorbed. [Warfarin](https://en.wikipedia.org/wiki/Warfarin) would be interesting too. Give a dose, wait 3 days, give them a bloody nose and watch them bleed to death. Another possibility are [binary weapons](https://en.wikipedia.org/wiki/Binary_chemical_weapon), where two relatively harmless agents are combined to make something deadly. [Isopropyl aminoethylmethyl phosphonite](https://en.wikipedia.org/wiki/QL_(chemical)) is a relatively non-toxic chemical, but when it's mixed with sulfur, it turns into highly toxic VX nerve agent. Another example was a case of [poisoned pet food](http://www.rense.com/general76/bitox.htm) where two chemicals (melamine and cyanuric acid) were put into pet food, and the resulting mixture caused a lot of pet deaths. Some plants might be interesting. [Oleander](https://en.wikipedia.org/wiki/Nerium#Effects_of_poisoning) leaves are pretty poisonous, it's pretty common, can be brewed into a tea, and the effects mimic a heart attack. Edit More ways to kill someone... If you can get away from delivering the poison orally, there are other ways. Binary poisons could be put into other things that are used together. Makeup, hair products, shampoo and conditioner, clothing, which would be sweat activated... Speaking of clothing, there are several poisons that can be absorbed through the skin. Thallium, [nicotine](https://en.wikipedia.org/wiki/Nicotine_poisoning#Toxicology), cyanide, [Dimethylmercury](https://en.m.wikipedia.org/wiki/Dimethylmercury)\, others. Simply put some on an article of clothing, bed sheets, shoes, and some time later they die. I also came across some interesting injested poisons. Hemlock is pretty poisonious, but a hemlock salad is boring. Quail are immune to the poison in hemlock seeds, and love to eat them, but it makes their flesh poisonous. 6 hours after the meal the target is dead. Rhododendrens and Azaleas are poisonous, including their nectar. Raise some bees in hives surrounded by flowering Azaleas. Give the victim the special honey, and 6 hours later the symptoms start, followed by agony, coma, and death. Methanol is wood alcohol which if ingested metabolizes into formaldehyde in the body. It takes 12-24 hours for symptoms to develop, by which time it's to late. Spike their whiskey and wait. \ some interesting stuff with Dimethylmercury. It's a mercury compound which is clear. It's super poisonous. It can easily go through rubber gloves. People who have smelled it said it smelled sweet before they died. It only takes 0.1 mL on the skin for a fatal dose. [Answer] Serve some a dish with some Amanita Phalloides fungus, they are reported to taste good and don't give symptom for two or three day, and once the symptom appear, [the situation is pretty bad](https://en.wikipedia.org/wiki/Amanita_phalloides#Signs_and_symptoms), leading to death in a about a week [Answer] This is a somewhat alarming question due to its potential real-life applicability, but I feel reasonably comfortable recommending a poison that is rather expensive and hard to obtain, namely... ## Water ... \*cough\* I meant, of course ## Heavy water, or $\textrm{D}\_2\textrm{O}$ (a.k.a. deuterium oxide) This exotic poison is already in our bodies, each of which contains enough naturally-occurring deuterium to make about 5-7 grams of heavy water (though most of that deuterium will actually be in the form of semiheavy water, a.k.a. $HDO$). Heavy water looks and, by some accounts, tastes just like normal water, but has sufficiently different chemical properties to normal water that when ingested in sufficient (though somewhat large) quantities, it will kill you. Specifically, [experiments with animals suggest](https://en.wikipedia.org/wiki/Heavy_water#Effect_on_animals) that replacing about half the water in your body with heavy water [will lead to death within about a week](https://en.wikipedia.org/wiki/Heavy_water#Toxicity_in_humans). So, let's tick off the criteria in the question: > > Delivered by ingestion (in food or drink) -- dosing can be a single > dose, or multiple doses over the span of a couple of days provided > symptoms do not start until after the dosing is complete. > > > Check. (Well, you do have to get the victim to drink 20-25 liters of water, but I never promised you a rose garden...) > > No strong off taste, odor, or color (mild tastes/odors/colors can > easily be disguised/masked by putting it in an appropriate preparation > though) > > > It tastes just like normal water -- no masking required! Check. > > Delayed action (hours to a few days after dosing is complete) so that > they don't associate what's happening with their last meal/drink. > > > Heavy water inhibits cell division, which in the short term will have no adverse effects. As I said, severe poisoning seems to set in after a few days resulting in death something on the order of one week after ingestion. Check. > > No gastrointestinal symptoms once the poison starts to take effect -- > again, so they don't associate what's happening with their last meal > or drink. > > > According to Wikipedia, "The mode of death appears to be the same as that in cytotoxic poisoning (such as chemotherapy) or in acute radiation syndrome [...], and is due to deuterium's action in generally inhibiting cell division." So: Check. > > Complete effect of the poison (i.e. total incapacitation) needs to be > within an hour, if not within the span of minutes, after symptoms > start to manifest. Needs to be incapacitating for a period of one week > minimum, if not fatal. > > > Okay, not sure about this one. I'm rather thirsty after writing this post, I think I'll go get a drink of water... [Answer] Harvest your own botulinum toxin from a swelled canned good or see Uncle Fester's handbook on how to make bootleg Botox. If you mix it in the food, it would cause gastro problems but not always. It is odorless and tasteless. By the time the symptoms show up, 2-7 days, it is too late for treatment. The ER won't suspect botulism because it is just one individual. Likely misdiagnosis stroke, Eaton Lambert, Myasthenia graves, etc. You could also dip a blade in toxin and make a very small cut on your victim. [Answer] Carbon monoxide is odorless and tasteless. Often called "The silent killer". If someone was sleeping or intoxicated they could die from breathing this without even realizing any symptoms. Depending on the concentration inhaled death can occur anywhere from 2 hours to less than three minutes. If you were to fail and the person only received acute poisoning,symptoms would include lightheadedness confusion headaches vertigo and flu like effects so suspicion would be minimal to none [Answer] Another possible poison would be gamma hydroxybutyric acid or GHB it can only be detected in a blood or urine for about six hours after ingestion. GHB is sold on the black market under advertising such as "cattle Anesthetic" I believe it is considered a date rape drug or knockout preparation it causes sudden loss of consciousness with amnesia afterward. It's use is highly dangerous particularly in an overdose or in mixed intoxication ]
[Question] [ We are at 2015 present, and assuming we travel back in time and meet the people from the same country but long ago (make it 1000 years ago). Can we communicate and understand whatever each other say? [Answer] Well, that depends: > > Salvē! Loquerisne Latine? Ovulis diabolo estis? > > > Did that make sense? How about this: > > Hwæt! We Gardena in geardagum, þeodcyninga, þrym gefrunon, hu ða æþelingas ellen fremedon. > > > Piece of cake, right? Well, it is if you know modern German, English, French, and preferably Dutch and Norwegian, too. It probably helps to hear it spoken, too: no intimidating foreign-looking squiggly characters. In other words, unless * you happen to speak an archaic language like Romanian (that's a lot like Latin, with a bit of Slavic mixed in. This is not precisely correct, but a modern Romanian would understand: `Salve! Locvace în Latină? Oul diavolui ești?`), or * took 5 years of Latin (which was a bit like the English of the time - few people spoke it natively, but it was the international language of business and science) in high-school * or whatever the ancestral lingua franca was in your corner of the world you're in a bit of a bind. PS: It's been years, so my Latin cases suck. If you actually know Latin, feel free to edit the Latin question and put the devil in the correct case... [Answer] If you're in Europe, your best bet is [ecclesiastical Latin](https://en.wikipedia.org/wiki/Ecclesiastical_Latin). Apart from minor pronunciation shifts, it hasn't changed much in the past 1500 years or more, and most of the Church hierarchy can speak or understand it. If pronunciation is a problem, you can try writing in it: the upper Church hierarchy was literate, and the written form hasn't changed. If you're trying to talk to commoners, you're mostly out of luck. There have been huge shifts in vocabulary and pronunciation in virtually all living languages in the past thousand years. [Answer] That depends, i would say. I am pretty sure your time traveller would be completely incapable of communicating verbally right after arrival. But he should be able to learn the language pretty quickly. Assuming he prepared for the voyage, he might have done some research and learned some of the mechanisms how the particular language has changed, which might help. The most solid approach, though, to me seems to travel back in steps of 50 or 100 years, stay for some weeks, try to adapt to the language, then travel the next step. That way he should be able do get accustomed in a way that would allow him to communicate immediately on every step, and thus also avoid some probably nasty misunderstandings. [Answer] A thousand years is a very long time, so most likely not. It still depends on the particular languages, though. An Englishman without linguistic training would not be able to understand [Old English](http://en.wikipedia.org/wiki/Old_English). An Icelander however might have a chance of learning to understand [Old Icelandic](http://en.wikipedia.org/wiki/History_of_Icelandic) once he got used to the pronunciation. I imagine that it could be like getting used to a dialect. I may be mistaken on this, though. [Answer] Well, if you are american (and I mean any place in America, not just the Northern part of it) you should learn your tribal/indian languages before time-traveling, because 1000 years ago there was no european here, thus nobody spoke English, Spanish, French nor Portuguese around here. I'm brazilian, so I speak Portuguese, and if I time-traveled to the region where Portugal is today, 1000 years ago, around 1015 they spoke a language called "[Galician-Portuguese](http://en.wikipedia.org/wiki/Portuguese_language#History)", and although the example I read in [Wikipedia](http://en.wikipedia.org/wiki/Galician-Portuguese#A_stanza_of_Galician-Portuguese_lyric) looks more like Spanish than Portuguese, I guess I could make do with my modern Portuguese. So I think it depends where you're from and how much in the past you're going. Be careful when you time-travel. [Answer] Language drifts and changes significantly over time and there is no definitive answer for that for any given language, but as an interesting example, [this article shows how English has changed over 1500 years](http://theweek.com/articles/545166/what-english-shakespeare-beowulf-king-arthur-actually-sounded-like) or thereabouts. It partly depends where you are as well- if you were in the US then you would need to have an understanding of the people living in your part of the country a thousand years ago and there is a good chance that they have died out altogether by now, so even finding a close language could be very challenging. If you are in China then the people would be quite similar and even if the spoken language had changed significantly ( and I don't know much about the linguistic history of the Chinese languages ) from my understanding you would still be able to understand the written word as that has changed very little over time. [Answer] Yes, they would. The trick is that verbal communication also includes some non-verbal bits. I remember an excellent exercise where the school group I was with read a scene out of a Shakespeare play (understanding none of it), then watched actors play out the scene. Our understanding of the scene was dramatically better than that of our reading. [Answer] # Emphatic YES. With one caveat... Arabic has been preserved for over a thousand years both in writing (using harakat and midoon vowels) and in spoken language. Yes, it has diverged slightly, but the written has been strictly preserved in the Quaraan - even the inflections of vowels. The Quaraan is not considered legitimate if it has been translated or altered and has strict phonetic structure. Absolutely an Arabic speaking, educated person in Morocco could understand a 10th Century Arabic speaking, educated person in, say, present-day Iraq. An Arabic-speaking person, even my own elementary Arabic, would be able to understand: بناء عالم بالنسبة لي even if it didn't make much sense, literally translated ("build a world for me"), in the [10th Century Renaissance](https://en.wikipedia.org/wiki/Islamic_Golden_Age). I do not know about Hebrew, if someone wants to chime in. Also, I am living in Abu Dhabi, so I hope this means 'our country,' in your question. [Answer] That's a curious question, never thought of that. I searched the web about my language (portuguese) and found out that 1000 years ago, we spoke latin. This language was perfected over time and eventually substituted by our actual portuguese. If a portuguese time traveler came to this date and tried to talk to me, there would be no way I could understand him. An history or language student, however, would be able to. Same thing with any language. So it's really a matter of who the traveler would talk to. If we managed to understand so many tribal languages, why wouldn't se be able to communicate with our antecessors? [Answer] well it depends on how old the language is and the history it have. few languages originated even before christ, such languages may have undergone numerous changes and might have modified way too much, but as per my knowledge and thinking any language we speak now it might be , it will be having its root from that past now also. Read this article [Wikipedia about languages](http://en.wikipedia.org/wiki/List_of_languages_by_first_written_accounts) it gives you a clear picture about how old are the languages and if you go on searching for the roots of languages one after the other most of the languages are created more than 1000 years ago. so assuming time travelling as you said, yes we can communicate with the people who existed 1000 years ago using the language we speak now. ]
[Question] [ Suppose that there is a species of dogs that are much more intelligent than humans and can speak. The humans know that the animal is smarter too. The only reason these animals can't rule over humans is because of their physical limitations (no aposable thumbs). They can learn faster, they are more creative, and they could build better technology if they had humans to actually implement it. They are easily able to communicate with humans because they can learn and speak languages. How would humans treat these dogs? Would we be hostile to them because they could be a threat or would we work with them? Note: the dogs have only shown signs of being peaceful, but humans are paranoid [Answer] As with all things of this nature, you're going to get a spectrum of human responses. Some people will fear the dogs no matter what. Some people will love them, some will want to enslave them, and it's likely that a majority will be neutral. However, there are several factors that will shift that spectrum and change the relative proportions of those opinions. 1. History. As David Mulder stated, if the dogs have been around for a while then their history will impact how they're viewed, and you can make this work however you want. If they've been historically benevolent, it's hard to imagine more than a small fringe that's against them. 2. Lab-created. Lots of humans have disproportionate reactions to anything lab-created as unnatural, so if that's the source you'll get a lot of knee-jerk hatred. 3. While this is normally a visual phenomena, I suspect that you might get an [Uncanny Valley](http://en.wikipedia.org/wiki/Uncanny_valley) effect if the dogs act almost, but not quite, human. This would give you a percentage of humans with an instinctive revulsion against the dogs. 4. If the dogs are cute (or at least photogenic) more people will like them. You'll get a more positive response from intelligent Golden Retrievers than say, German Shepherds. 5. You will get a more positive response if you avoid "attack" breeds, like Pit Bulls (I know most of that is BS, but we're talking about general trends and perceptions here, not reality). 6. If the dogs are that intelligent, they will value positive PR and will take active steps to control their perception by humanity and make it as positive as possible. [Answer] Realistically it all depends on how the dogs have shown up. Honestly, you can design such a relationship in any way you want it. If they have been there for all of history then they can both be masters using machinery they had humans design in the far past or simply live along side or even be the slaves of humans. If they were created in a lab there would probably a lot of fear towards them and they would probably be kept locked up in various huge companies that would exploit their intellect. And if they just suddenly appeared out of nowhere they would probably be eradicated as a threat (taking human history into account). But still, if you want to build a world where they suddenly appeared and became the best human friends then that's possible as well (just give them a common enemy and there you go), it's all possible and the question is far too broad to give any serious advice. [Answer] While there would certainly variations, I think for the dominant treatment there would be only three possibilities: * Enslavement. If we can keep control over the dogs despite their intelligence, then the dogs will effectively be enslaved. Note that this is true even if those dogs are loved: We love dogs as pets; we don't usually love straying dogs. An intelligent pet would effectively be a slave as well. * Competition. If neither species can dominate the other, the end will be that both species treat each other as equals. Humans would appreciate the dogs' superior intelligence, and the dogs would appreciate the humans' better dexterity. Of course that does not mean that this would be true in every individual relationship; after all, human slaves existed through all of history. However in the whole picture, there would not be one species that enslaved the other. All in all, dogs and humans would compete against each other in the same way humans compete against each other. * Dominance. If the intelligent dogs were sufficiently intelligent that they can control the humans, they most probably will do so. In that scenario, the world would be ruled by the intelligent dogs, with the humans fulfilling whatever role the dog society assigns to them. If the dogs are very intelligent, they will be able to do so in a way that the humans don't even notice that they are dominated by the dogs. [Answer] Humans are rarely uniform in our approach to life, and I think that would include our treatment of dogs who are much more intelligent than humans. And instead of typing "dogs who are much more intelligent than humans" over and over again, I'm going to call them "peabodies." It seems likely (because you don't say otherwise) that the peabodies have been around a long time -- more recently than humans, I'll assume, because dogs in general are a more recent development. But I think we would've encountered them before, say, the bronze age, though not necessarily on all continents. Those who cooperated with the peabodies would likely prosper a lot better than those who didn't. Considering that for a lot of our existence, getting our next meal was often a problem, I think there'd be a lot of advantage toward cooperation. Those who used the peabodies' brainpower would tend to reproduce better and defend themselves better than those who didn't. And the peabodies wouldn't make very good slaves -- those unhappy with their lot would only have to hold back in inventing, and, of course, they'd know it. Of course there would be exceptions, because humans of any stripe can be irrational. When Benjamin Franklin invented the lightning rods, churches considered them blasphemous. But when church towers kept getting hit by lightning and structures protected by lightning rods were kept safe, the lightning rods won. We're a species with a certain frequent self-defeating perversity to our thoughts, yes, but we're not, generally, idiots. [Answer] the dogs have only shown signs of being peaceful They're canines, ergo hunters and predators. Thus, your caveat is fundamentally flawed. Anyway... without bipedalism and opposable thumbs, they can't use tools (thus no writing, controlling fire, etc, etc, etc), they aren't a threat to us. Did they become intelligent before or after the split from wolves? IOW, are wolves intelligent, too? I can really imagine super-intelligent wolves being a significant threat to Stone and Bronze Age man. The "fear of forest" which engendered the story of Peter and the Wolf would have been magnified 1000x fold, and we'd have done our best to exterminate them -- which we would have, because of range weapons and poison -- ASAP. If the intelligence came when they were dogs, I can imagine them knowing their limitations, latching on to us, and reminding us at every turn that they're no threat. Culturally, this would have changed the course of religious development (do intelligent dogs have a soul?), and limited the settlement of the north (super-intelligent beings typically not liking to be used as beasts of burden). [Answer] ## These dogs would very quickly be in charge of the world, beginning around the time that humans first learn to herd animals rather than hunting them. Humans would probably start the war (the dogs are taking their livestock), but the dogs would retaliate by attacking human settlements, killing all the adults and taking away babies which they would "domesticate". Their newfound pets would allow them to overcome their lack of opposable thumbs. Fast forward 20,000 years and we have cities with the more intelligent dogs being at the top and humans being second class citizens. [Answer] If these uberdogs lived and evolved along with us since the dawn of the species, then they were competitors, just like humans treated other humans as enemies for resources and territories. If there were another predatory species available at the time, we would have domesticated that for protection. During history, there would be two parallel civilizations, with benefits and problems on both sides. We would have furry slaves and they ape slaves. After all, if we can enslave our own peers, nothing will prevent us from doing the same with another sentient species. Dogs as we know them in their many breeds will not exist. A quality of us as sentient species is the size of the skull, which makes pregnancy a tough affair for women. It would be the same with the Homo Canem. The reproduction rate wouldn't allow a selective breeding -not to mention that a sentient species is already versatile enough to work tools and do everything we need from them as slaves. And when the slavery will end in favor of better regimes, they will make for useful allies/citizens. At best, there will be a series of ethnic groups best fit for a given environments. In modern times, an open-minded human neighbor will ask the canine family from the other side of the street to join them for a grill party -and make that steak so blue that it makes me happy, man! [Answer] Re created in a lab: what if they were created to be our leaders? Or at least the administrators, with human top-leaders telling them what to do. This would be done to remove the self-destructive traits that bother us in large groups. Why dogs? It was unthinkable to manipulate the genes for the brains/minds of humans, both for ethics and the real fear of creating our replacement as a species. Dogs, as you see from the diversity of breeds, have a very flexible genome. And, what better to not become a monster AI but to love us unconditionally? ]
[Question] [ I am creating a tundra-nomad inspired culture, but I'm having trouble figuring out how to design instruments that will seem believable for these people and also be unique when compared to the real world. The nomads are primarily herders who control large, yak-like beasts for milk, meat, and wool, and make their money from trading these materials in markets. One of the ways they pass the time is through playing music. I have thought about making a pipe-like instrument made from an animal tusk and stones, but I still have no idea how it would sound or be played on. Any help or suggestions would be great! [Answer] Strangely, this solution might best be designed by looking at how we classify all of Earth's many musical instruments. You see, once you get out of middle school's music program, it turns out that there are a multitude of musical instruments throughout history, more than a few of which are unique. The people who study these want to know how to classify them, and even the traditional European instruments you're familiar with exist in a dazzling variety of modifications. There's not just one saxophone, but an entire spectrum of the things... those are (mostly) classified according to the key they are made to produce. But what do you do about those instruments that are more exotic? Where does that one-of-a-kind accordion-or-maybe-it's-a-hurdy-gurdy belong? Eventually, these people got their act together and fashioned a system that should be able to (in theory) describe and classify any musical instrument. Let me introduce to you the [Hornbostel–Sachs system](https://en.wikipedia.org/wiki/Hornbostel%E2%80%93Sachs). By being able to describe any plausible musical instrument, it can already describe those you'll design but haven't managed to design yet. And it lets you easily explore the possibilities, out to the very edge of what is plausible. At its most basic, it turns out all musical instruments go into 4 broad categories, based on what is vibrating to create the sound: 1. idiophones 2. membranophones 3. chordophones 4. aerophones The first (idiophones) describes instruments that vibrate themselves to make sound. Bells come to mind, and cymbals. Chordophones vibrate a string, so everything from the guitar to the piano. Aerophones are anything in which a column of air (such as from a pipe organ) vibrate to make the sound. Some of these you might be able to rule out right away. Do these people have string available to use for musical instruments? It seems to me that even the Inuit might manage that trick, using animal gut. But in many cases, strings need to be stretched out over some chamber (hollow or not), so they'd have to get creative. Start exploring on the Wikipedia page, and if you need to dig deeper it links to other resources to continue research. [Answer] Long bones are well suited for making flutes, like [this](https://news.cgtn.com/news/786b544d34677a6333566d54/index.html) ancient examples shows [![enter image description here](https://i.stack.imgur.com/TJCQ6.jpg)](https://i.stack.imgur.com/TJCQ6.jpg) If they happen to find canes they can also make similar instruments with those. They just need to drill/carve holes at the proper distances in the body of the flute, ensuring that they sound well in tune. As somebody who struggled to properly tune a guitar, this can be tricky. And with skins and wood they can make various types of drums. Playing the flute would require the player to blow through it and then close the holes to obtain different sounds. The sound might be not as clean as with a modern instrument, but sometimes that's part of the color of the instrument. For the drum, well, it's not rocket science, either use hands or sticks. [Answer] If it is a nomad-like group, the music will be fairly simple, rhythmical, and probably repetitive. Simple drums could be made from stretching some animal hide over a wooden bowl. Flutes and simple horns could be formed from animal bones. The musical style, of course, would be nothing like modern. Be sure to scale it back from even modern music--that means no major/minor scales. I would imagine the emphasis of the music would be words sung, but not in a choir fashion. Have one person be a 'singer'--they might alternate between their voice and a flute. Drums could be used to double the rhythm of the singer or just supply a steady beat. I would caution you not to make it too complicated, flashy, or intricate. Simple rhythms at a moderato or andantino tempo, accompanied simply, would serve best. [Answer] ## Let's be inauthentic "Yak-like beasts" implies alien, and alien beasts want alien music. Posit the hair (wool) of these beasts is convergent to yak hair in function, but not in chemistry. To wit, when it is soaked in an acid, such as the acid found in the stomach of a hungry yak when it is slaughtered, the polymer of the hair readily dissolves. When the water is extracted as it is mixed with salt from an alkali flat in the presence of a little oil to keep a smooth surface, it repolymerizes and rapidly resolidifies. By making this yak rayon and spinning and winding it deftly around one of the creature's horns, you can create a spiral of a hard, tough polymer that gradually increases in size. Pull it off and play it with a faceted hammerstone (think guitar pick with some heft), and you can make unique noises by banging and stroking the coil. A musical scale is introduced by making a unique pattern of fusions at various lengths along the coil with a bit more yak rayon, creating segments that isolate with a defined harmony. It is also possible to place one of these inside another, playing the one on the inside with the hammer-pick but hearing the sympathetic vibrations on the outer one more clearly. I have no idea if this works. I ought to catch a yak-like creature and find out. Is Abydos hot this time of year? [Answer] If you want to get authentic, it's drums and [Jew's harp](https://en.wikipedia.org/wiki/Jew%27s_harp) (don't get confused with the name). [Tundra song](https://youtu.be/Iurw8v4XoGA) [Answer] Bagpipes. Many, many different communities around the world have invented these independently. How they're tuned and whether they have drone pipes will vary, but the basic construction is the same. All you need is animal hide for the bag, wood or bone for the pipes, and animal fat to seal the joints and keep the hide in good condition. If you want this to be be a bit more funky, perhaps these ones aren't a solo instrument. Instead there's a much larger bag on a frame, a couple of people blowing it up, and a couple of people playing cross-melodies on two chanters. Or four chanters, with some ocarina-like finger layout for each hand. [Answer] Rythym is the simplest form to cover, it can be created by something as simple as banging two sticks together, to as sophisticated as something like a snare drum. In your case, one of the main resources in nomadic civilizations would be animal furs and bones, allowing percussive instruments to be made from things like pelts. For portability, these would mostly be made of hide, with a structure made of something like sticks or bones. Bone instruments are extremely valid, as bone is known for having some of the most desirable acoustic properties known to man. In order to design a unique instrument, you need to first understand music systems. For example, modern western music uses an equal temperament system, which while flawed, is extremely refined compared to more archaic music systems such as just temperament (<https://en.wikipedia.org/wiki/Equal_temperament>) Temprement is dependent exclusively on instrumental harmony, however, so if you want to avoid the rabbit hole that is music math, you could create harmonies and melodies acapella, as opposed to instrumentally. Tying all this into your pipe-like instrument, the shaft would almost certainly be made of either horn or bone. This would be carved down to a specific length to create the desired pitch. In order to avoid the aforementioned temperament systems, the pitch of the instrument would be controlled similar to a bugle, almost entirely by the player's mouth. (<https://en.wikipedia.org/wiki/Bugle>) If you want to add an extra layer of sophistication, you could add holes at the octave points (1/2, 1/4, 1/8, 1/16, etc.) allowing the instrument a much wider pitch range. Keep in mind that each hole before the desired pitch needs to be covered. (like a recorder) so you can't have more octaves than the player has fingers. (this shouldn't be an issue, most instruments have three to four octaves max) To give a general idea of how this would look, let's assume we have a tube 67cm long (~26 3/8in) that resonates at middle C. The first hole would be drilled halfway up the tube, the second hole would be 1/4 up the tube, and the third 1/8 of the way. This would allow people to play music sounding somewhere between a horn and a trumpet while being much more resonant since it's made of bone. Its tone would be described as resonant and warm, while still carrying a similar mood to brass instruments created today. ]
[Question] [ (please see note re: name controversy at the end) My world needs a captivity environment that convincingly tends to cause [Stockholm syndrome](https://www.webmd.com/mental-health/what-is-stockholm-syndrome#:%7E:text=Stockholm%20syndrome%20is%20an%20emotional,toward%20an%20abuser%20or%20captor.) in its captives, leading them to willfully serve their captors as pirate lackeys. The caveat here is that the prison works on people of average status as well as the lower class captives. The criminal underground culture of this captivity must induce a loyalty to the illegal lifestyle (the way common impressment worked) but at the higher cost of their regular lifestyle. This is a captivity which tries to cause “regular people” to join them, not merely people with nothing to lose. # The captors The captors are pirates [operating in a secluded haven](https://worldbuilding.stackexchange.com/questions/225150/why-cant-the-military-stop-my-hidden-pirate-haven-from-illegal-gambling-and-smu). No law enforcement knows where they are. The haven is in an environment that can’t be escaped from without aid of a ship. The captors are not seeking ransom, they are trying to [impress/recruit captives into service](https://worldbuilding.stackexchange.com/questions/224843/the-deaf-prisoner-got-her-secret-message-and-the-pirates-never-knew-how-was-tha?noredirect=1&lq=1). # The captives Captives get here accidentally, not abducted. Think like people sailing around and stumble upon some uncharted island, and BAM, captured. So that makes a difference in class: they had lives and money. They are from a 19th century middle class society with no material needs or chemical dependencies. Textbook impressment normally targets the lower class. The emotional state can be whatever works however. The captivity environment does not have to be perfect, it must only produce severe psychological pressure for these people to develop Stockholm syndrome. # Limits This is targeted for a general audience so gore and violence won’t work for the story. I included the psychology tag for this reason. What would the captivity in this setting need to afflict captives with Stockholm syndrome? * Per comments: [base technology is steam powered trains](https://worldbuilding.stackexchange.com/questions/224764/hell-trains-powered-by-a-cold-reaction-what-can-the-condensers-use) and [airships](https://worldbuilding.stackexchange.com/questions/225212/how-to-maintain-large-ships-in-hostile-atmosphere). The world is [a harsh planet largely unexplored](https://worldbuilding.stackexchange.com/questions/183710/how-could-we-modern-humans-get-established-on-a-hot-planet) with airships occasionally venturing out beyond the cities. These become victims when they come across the haven. --- The name "Stockholm syndrome" is controversial however the phenomenon is not. The term was chosen for this question because the outcome of that process is common knowledge, thus using that term is concise and effective. If you dislike the term, then please substitute the following in its place: "a psychological condition where the captives who are put in danger, have developed sympathy, affection, and loyalty for the persons who cause their danger" [Answer] # Better Jobs (or at least the perception of better jobs) If the pirates give the captives responsibilities, good conditions and some degree of freedom/control over their own work, why wouldn't they want to stay? It's worth noting that these jobs don't have to be GREAT, they just have to be better than (or perceived as better than) what the captives had before. From the [Wikipedia Article on Stockholm Syndrome](https://en.wikipedia.org/wiki/Stockholm_syndrome): > > The hostages defended their captors after being released and would not agree to testify in court against them. It was noted that in this case, however, the police were perceived to have acted with little care for the hostages' safety, providing an alternative reason for their unwillingness to testify. > > > A factor in "Stockholm Syndrome" wasn't just the captives feeling positively towards their captors, but feeling negatively towards the police. A combination of (1) satisfactory circumstances given by the pirates and (2) captives having some hard feelings towards the outside world (whether that's their previous employers or the government or whatever) should motivate the captives to want to stay captive. What conditions make for a "better" job? Well, if I was to name one, I'd name autonomy. If you have a captive clean your space station, don't give them a detailed list and a ton of micromanagement. Let them know (1) what their goals are, (2) what tools they have to do it, and (3) how they'll be held accountable. Then be fair and honest with them. The best way to convince prisoners to like the pirates is for the pirates to be likable. Give them good (or at least better than the outside) circumstances and they'll be loyal. [Answer] This is bit of a frame challenge. In popular culture, we understand Stockholm syndrome as hostages becoming sympathetic of their captors, and defending their actions even after the fact. I'm going to explain my understanding of the genesis of this syndrome because I feel this is important to the point, and also it might cause someone to learn something. Feel free to skip it, or to do your own research and come to your own conclusions. --- The concept was coined by criminologist Nils Bejerot as the "Norrmalmstorg syndrome", after the name of a square in Stockholm where in 1973 a bank was robbed. 4 hostages were taken by one man with a second man joining later, and 5 days later were released after a police assault and all was well. Ish. Kristin Enmark, one of the hostages, was the object of that diagnosis. She was allowed to call the Prime Minister and pleaded for him to allow the hostage takers to walk away. Later, Enmark criticised the authorities that freed her, and she refused to be carried out on stretchers, insisting on walking out instead. She didn't appear traumatised, but rather "fresh and alert". Bejerot offered the explanation of this syndrome. Enmark also notably declined to testify in court against her captors, which furthers the hypothesis. But it's very important to note Bejerot didn't speak to Enmark before diagonising her with this new ad hoc "Norrmalmstorg syndrome". On the call with the PM, he told her that "you will have to content yourself that you will have died at your post". Police used tear gas despite threats by the hostage taker that he would kill the hostages if they used gas. Meanwhile, Enmark at least wasn't physically harmed by the captors. The most favorable framing, I think, is that Stockholm syndrome is an unexpected reaction to the trauma of being held captive under intense stress and fear for one's life. This in turn begs the question: What is the expected reaction and why is it expected? Little research has been done on the subject of protracted hostage situations, fortunately owing to them being too infrequent, so I think it would be unwise to make generalisations about it and that it's dubious there is much to learn from Stockholm syndrome scientifically. A different framing is she was a woman in the 1970s and she didn't react victim-y like she was supposed to. That was sufficient to come up with this Stockholm syndrome on the spot without needing to question the actions of the good guys further, like it was just some case of female hysteria. --- The point of all of that is, in my opinion, Stockholm syndrome is rubbish. It's a popular concept that has no basis in reality. We know these days there is no one standard way people react to trauma. Stockholm syndrome was coined in response to one event, to (wrongly, no less) explain the immediate reaction of one hostage in one unique circumstance. I'm afraid there is no such thing as a single reason that can neatly explain why any and all people from a variety of walks of life would fall in love with the pirate way when their freedom is forcibly removed, so your question doesn't really have an answer. What you can do in your case is easily explain why people don't leave: because they just can't. A remote, uncharted island in the middle of a vast ocean is extremely difficult to evade if the pirates take away their ships, maps and instruments. You could let the captives to roam freely on the island, and they might very well try to build a raft, and they'll most likely never to be seen or heard from again because they'd be dead on the ocean. That would disincentive others to try. The pirates don't have to do a thing except welcome those that wish to join, because then the choice is live on your own or with other captives, live with the pirates and all the luxuries that they have, or probably die the high seas. Those that decide to live with the pirates might eventually join them in piracy, especially if they're given status among that group. They might convince others to follow suit. And if they escape or are freed, they might appear as completely converted to the pirates' cause. But from a certain point of view, that's just making the best of it. You're stuck on an island, your past life is effectively out of reach. If you accept that circumstance as an irrevocable fact, joining the pirates is the best, and approximately only, opportunity you have for a better life. It either gives you access to a ship that can be used to escape, or gives you something to do with your life beyond simply surviving and perhaps reclaim some of the wealth and status you previously had. You, the author, will have to make some concessions that not everybody will accept to follow the pirate life, yo ho, yo ho, and you'll have to resolve what happens to these people. For those that do choose to follow the life, they'll realistically have different reasons for doing it, because they're simply different people. And if they somehow find their way back to their previous lives, then you can have some guy talk to the press dismissively about their experience and brand them with the Stockholm syndrome all you want. [Answer] The pirates are super hot hotties! [![ateez pirates](https://i.stack.imgur.com/sfiUO.jpg)](https://i.stack.imgur.com/sfiUO.jpg) <https://www.trendsmap.com/twitter/tweet/1384884004525072384> And also they are great people. Fun to be around. Huge senses of humor, artistic, daring, mischievous. And also hot as all stink! Not only are the pirates awesome people, they act like your accidental captives are just as awesome. They team up with captives to prank other pirates and everyone laughs. One might lend a captive some sweet pirate pants, so your captive could practice her swagger. There are dance parties every night and the pirates are super patient with your captives who need to learn how to dance. Who could avoid thinking that these sweetest of pirates are anything but the greatest?? [Answer] (I now realize this is a quite extreme answer, sorry for that) How do 23 military control a population of thousands of forced laborers.. Conditioning Nothing else is needed. In the long run, prisoners behave, when other prisoners who don't behave disappear or get punished in other ways. You can force people to hard labor, 24/7 , survivors will obey. They could even love you, or pretend to. *Some notes about Stockholm* syndrome** Actually I don't believe in Stockholm syndrome as a real syndrome. It is not a disease. It is a means to survive. Some victims need help afterward because they can't explain their own behaviour and feel guilty about it. Especially when lots of people died. The therapist will diagnose the struggle of the victim as post-traumatic stress, A modern, (eventual) rationalisation or label for this, giving some comfort because it is designated as a disease, called "Stockholm-syndrome". The term is often misused in political discussions. [![enter image description here](https://i.stack.imgur.com/zzQB5.png)](https://i.stack.imgur.com/zzQB5.png) [Answer] The most concise answer I can give is to look at a comic regarding Elan school. Googling Elan School comic will pretty much take you right to it. What it entails is a correctional facility for youths ran essentially by a cult. It was not physically brutal as much as it was psychologically. Bizarre social norms that seem crazy to us now, but strictly enforced within, must be adopted for months or years at a time just for the hopes of escape being possible. If you don't start acting as demanded, you don't eat, you don't sleep, and you are also punished if the people around you don't conform, pressuring others to enforce rules they themselves only follow to survive. Problem is, those who adapt are given increasing power over those who do not, the sort of power that is encouraged to be abused. This turns into people who have been in the system for a year or more having relearned how to live, living by normally alien social norms, which by now is their entire world and comes with perks largely including what ever abuse they want to give to the newer joins. It's quite the read, and the facility operated for about 40 years, due to the expansive levels of confinement that make escape practically impossible. Even parental visits and contacts are strictly monitored and punished if the kids don't follow their scripts and try to get their parents to do something to help. They get used to this new life over a year or longer then enjoy enough of it to return years later as staff once released. [Answer] # Reward-based incentives Your captives are rewarded for good, or beneficial, behavior. This starts with their first landing - they are treated very well by the current inhabitants (previous captives) and convinced that this is the good life. Resistance to accept this new home can result in some benefits or privileges being revoked. ## Of course, this is a Ponzi-scheme Over time the number of captives will outnumber the captors, so you need a perpetuating model. One such model is to reward your current captives based on how well they treat any new captives. Kind of the inverse of the [mythic 5 Monkey Experiment](https://skeptics.stackexchange.com/questions/6828/was-the-experiment-with-five-monkeys-a-ladder-a-banana-and-a-water-spray-condu). ## Or you need time This reminds me of a favorite movie - [Papillon](https://en.wikipedia.org/wiki/Papillon_(1973_film)) - where one of the characters is just ambivalent about leaving after a lengthy 'imprisonment' on an island. ## But, maybe it is truly better Given your description of steampunk and airships braving to leave the cities, perhaps early ships carried advanced technology and advanced machinery. These technological wonders, and their creators, continued to collaborate while in captivity to the point that a [Wakanda](https://en.wikipedia.org/wiki/Wakanda)-esque society evolved. This society is deserved of protection. [Answer] Drugs. Lots of drugs. On Pirate Island, the food options are very limited and one of the two staples is naturally high in compounds that induce suggestibility. If you drink a slightly GHB laced pineapple juice every morning, you'll do what your boss tells you to. ]
[Question] [ In a world which to a visitor coming from our own world would appear to be identical to our own, the mental processes (thoughts, emotions, memory) do not occur in the brain. That is, memory isn't stored in the brain and it is not the brain that is "doing the thinking". Instead the brain is a receiver for information passed to it from the incorporeal soul, in the same way that a radio receiver receives a radio signal. I already said the world is identical to ours in all respects (except that thoughts don't happen in the brain), but I want to emphasize the following: 1. To the scientists of that world, when they use current medical imaging methods like MRI, PET, EEG, and whatnot, the brains of people from that world look identical to brain activity images of people from our own world. 2. The people of that world hold the same beliefs as we do. That is, some do believe in a "soul", but there is no proof for it, and most scientists believe that the soul and telepathy are superstitions. Scientists of that other world, like scientists of our own, believe that memories are stored in the brain and that thoughts originate in the brain, and they interpret images of brain activity according to those beliefs. 3. There is no measurable electromagnetic or other "transmission" from or to the brain beyond the well-known electric activity of the brain itself. In that other world, the soul and the brain exchange information in a way that current technology (in both worlds) cannot detect. What observation would prove to a scientist that the brain is receiving thougts and memories from outside instead of thinking thoughts and storing memories within itself? [Answer] It would be visible during brain recovery. The brain stores information in various ways, including as feedback loops that remain active for years if not your entire life. Should sections of the brain be damaged and repair themselves the soul's transmissions would restore those, which suggests that these processes are stored somewhere. After enough functions of the brain can be charted simultaneously with accuracy you can determine the information comes from essentially nothing. [Answer] My first thought was that it would be impossible to discover that the brain was only a receiver due to: > > There is no measurable electromagnetic or other "transmission" from or to the brain beyond the well-known electric activity of the brain itself. > > > However, just because we can't detect the signal directly does not mean we cannot infer there must be a signal or connection to something else (the soul). The main factor what would control whether we could discover this connection is the location of the soul. If the soul is spatially located in the brain, we may be out of luck. However, if the soul is free-floating and occasionally becomes somewhat distant from the body, we have an opportunity for detection. # The Discovery Bob was having a great time preparing for the costume party. Since the theme was Space, he knew there would be a number of astronaut costumes, but he also knew that nobody would have a helmet coated with iridescent unobtainium, as his lab had only announced the discovery yesterday. What it hit it was going to be! What Bob had not counted on was the strange effect when he first put on the helmet: complete darkness, silence, and a sense of dizziness! He had no way to know that at that (un)fortunate moment, his soul had drifted far enough behind him that the helmet passed between it and his head... and, crucially, that iridescent unobtainium happened to block the soul-signal, which cut off all physical senses! Luckily, he was seated at his workbench when the signal stopped. His head tipped forward exposing a direct line between his soul and the lower part of his brain. With the connection reestablished, Bob's senses returned and he straitened up... only to "black out" again. When he realized what was happening, all thought of attending the costume party left his mind. There was amazing new research to be done! --- That is how I think the discovery could be made. The only additional requirements, besides those stated in the question, are: 1. The soul must, at least occasionally, be spatially separate from the brain 2. There must exist some material that can block at least the soul-signal, and possibly the soul itself, from reaching the brain. [Answer] I think [Occam's razor](https://en.wikipedia.org/wiki/Occam%27s_razor) would rule out the possibility that you describe. You have a sample brain which behaves in all the observable ways like a human brain, with no observable differences. Therefore the simplest explanation is that the sample brain is a human brain. Adding the additional feature of it being an antenna for receiving a stream coming from somewhere else conflicts with the entia non sunt multiplicanda praeter necessitatem on which the razor is based. > > Occam's razor, Ockham's razor, Ocham's razor (Latin: novacula Occami), or law of parsimony (Latin: lex parsimoniae) is the problem-solving principle that "entities should not be multiplied without necessity", or more simply, the simplest explanation is usually the right one. > > > From a scientific point of view there is no need to add the antenna concept to explain the working of the brain. However, if you want to use non scientific approaches there is nothing preventing you from postulating the existence of this antenna, which should be accepted as a matter of faith, not out of reasoning. [Answer] Unknown processes Currently we simply don't know how and where memories are created. We have very prevalent theories, but in the end we don't know. Now imagine we have scoured the brain, separating the noise of the neurons and the true working processes. Categorising and organising the signals to a comprehensive map, so if we see a certain combination of signals in a certain combination of neurons we know exactly what has happened. If we have done that for the full brain and not found the memories and thinking, the conclusion can be that it is extracerebral. The problem here is that the conclusion might be that we simply don't understand the way memories are stored, or that this activity is the memory. If you have no proof of outgoing signals, there is no reason to assume them, so you look internally for the cause of memories. As the activity and growth is the only sign, it must be the memories in some way we just don't understand. The sum might be larger than the whole. Imagine having a computer that has wifi, but you can never detect it. The wifi antenna doesn't exist in this case. The computer is the antenna itself, just because it is an computer. Now you can run some processes, but you can also access the internet. You know the internet exists, but how would you ever know where it comes from? You can scan every bit of the hardware, know what process it does, but as you don't know it can receive wifi signals you can't say with certainty it is coming from outside the computer. It will not stop hypothesis, research and more, but being certain if you can't find such signal is impossible. [Answer] You could have a situation where an external event coincides with numerous people, in distantly-removed lcoations, all simultaneously having the same strange thought. For instance, some sort of astronomical or supercollider lab event could broadcast "thought noise" that results in entire crowds of people in Tanzania, Wyoming, and Iceland all simultaneously thinking for a moment, in their own native languages, that if they replaced their right hands with cubes, there would be three moons in the sky next week. Then someone could notice that the places these occurred lined up in a way that indicated the source. Obviously this is an observation based on accident, not experimentation, but you didn't specify, and is a way you could set up the narrative for the discovery and "proof". [Answer] The transmission itself must be observable and reproducible. Imagine an experiment left running somewhere remote like Antarctica. It doesn’t find what it set out to, but researchers notice clear signals when a human is present. Controlled research develops along these lines until there is a clear correlation between a human forming a memory and the production of a specific signal. At this point, serious scientists may suspect the brain may be transmitting memories rather than storing them, but the predominant view will likely be that the transmission is merely a leak occurring when the brain stores memories in itself. To really prove that a soul is storing the memories will require a little more world building. For example, do animals have souls? Are human memory transmissions universal in their encoding so that they are ultimately as understandable as video compression algorithms or is every individual’s transmission pattern unique? Does the soul or its receiving antenna have a location in space? To prove memory is not stored in the brain, it must be possible to give someone a memory artificially while certain that the brain is not involved. Here’s a scenario that might work without taking your world too far into Twilight Zone territory. Let’s say that memory transmissions are far too personal and complex to decode, but they don’t start that way. Data shows remarkable consistency in the faint signals of newborns. They figure out how to boost the signal and find materials which block it. Now scientists can send a memory of birth at the amplitude of adult memory signals. Point it directly at the brain with the torso blocked and no memory is formed, but block the brain and point the signal at the torso and subjects consistently gain a memory of being squeezed through a dark place that makes them behave awkwardly around their mothers. Ultimately, nothing will prove the existence of a soul per se, but proving that memories are stored outside of the brain is achievable. [Answer] Lobotomy has no effect on personality or intellect, because those come from the soul, not the brain. Corpus callosotomy never causes alien hand syndrome, because the two halves of the mind are still fully connected in the soul. Surgeons would notice that brain injuries often have no effect, and report that large areas of the brain seem to be about as useful to the mind as the appendix is to the digestive tract. This would later be contradicted by fMRI studies showing complex responses to thought, memory and external stimulus in these "useless" brain areas, leading to long and heated arguments in the scientific community about the purpose of the frontal and temporal lobes. [Answer] Artificial Intelligence projects based on the brain would fail. Even if the brain is somehow too complicated for us to understand, as long as we can take a perfect atomic-level 3D image of the brain, we could reproduce it digitally. If the brain is a receiver, the digital brain will fail as presumably it has no "soul" and nothing would transmit to it. However, if the brain is a thinking machine, then our digital brain should work. This is beyond our current level of technology, so it would have to be at least a bit more futuristic world than ours. Of course, if we could prove/disprove the soul with our current technology we would have already have done so. [Answer] By hypothesis, you can not detect the transmission. The only avenue left for discovery is that the transmission can somehow be impaired or intercepted; or, more precisely, some phenomenon happens that can be most readily be interpreted as a thought-transmission being jammed or intercepted. If people can measurably often and predictably retrieve some one else's thoughts and memories, for which any other explanation can be excluded, at the very least you can prove the existence of telepathy. Another possibility is that, just like one device can detect those transmissions, and that device is the human brain, the same device can interfere with those transmissions. For example, someone in an insulated, soundproof "room" in the middle of a capsule hotel is performing some tasks; and we first notice, then can measurably and reproducibly demonstrate that their results are different (indicating a lower IQ or reduced memory recall efficiency) when the hotel is packed full of people (a fact which our user could never ordinarily know). This would mean that those other people's brain matter has a shielding or jamming effect. [Answer] # Is it? People have already mentioned incredibly clever ideas such as interference and the effects of brain damage, however I don't think those are enough to really prove interaction with the soul. If interference was possible, there would be a problem with people standing too close to each other and their information getting swapped or corrupted. This isn't necessarily a problem, depending on the scale of how much/how easily interference happens, but definitely something that would hypothetically be visible on brain scans - violating the first bullet point. For brain damage, it depends on how you interpret the radio receiver analogy: if you cut a chunk of a radio off, you'll get results ranging from perfectly fine to no longer functioning (but most likely not functioning great anymore), just like with what we see in real life with the processor-y brains. Obviously this depends on how much work the brain is doing. Does it have to decode the message like a radio receiver? Is it just redirecting data? With current stipulations, it's really hard to get a reasonable experiment that goes with your premises, and it more or less reduces to a game of interpretation/guessing at loopholes - neither of which is the point, as far as I understood it. --- Why is the soul the thing doing the processing? Why not the brain? What effect does this have on your story/world? Answering these questions is the key to understanding how people will discover that the brain is simply a receiver for the soul. Maybe later in the story the villain puts one of the side characters into a "coma" by disconnecting their soul using some sort of information blocker. Maybe souls can interact with other brains, meaning telepathy or mind control. These concepts/abilities would probably be found earlier in the story by accident, or experimentation. Do these violate some of your principles? As I understood it, yes! I haven't come up with great examples at all. But you need to find some example of what your concept does for your world, and that will help you understand how it is found. [Answer] > > What observation would prove to a scientist that the brain is receiving thoughts and memories from outside instead of thinking thoughts and storing memories within itself? > > > We are starting from a world identical to our own - brains appear to work as "processors", not "antennas". In our world, the scientific community does not acknowledge the existence of the soul1. So, we are looking for a phenomenon / event that has never occurred in our world, that would prove2 that in that world, brains are conduits for souls rather than thinking meat or flesh drives. ## An eye-opening global phenomenon * Maybe there's a limited amount of souls, and once the entire human population exceeds that number - no more babies are born3 or, if souls are "recycled" (reincarnated or just reallocated without any knowledge of their previous lives), than the human population reaches a hard limit - where only when someone dies a new viable baby can be born. * Or maybe some kind of pathogen messes up with the soul/brain connection - this could be something banal and morbid as unexplained deaths from damage to a minor and little understood part of the brain, but would be much more interesting if we get creative - for example, a virus/bacteria/parasite which copies some of the memories of one host to anyone catching it from them, or a disease jumping from one species to another causes people to behave like animals and vice versa, or even something that causes a complete "soul transfer" - where one person suddenly gains the consciousness, skills and memories of another (instead of or in addition to their own). * Finally, maybe it's something that affects everyone in an area in a way best explained by memories/thoughts being received rather than produced locally - such as all the people in a mall suddenly becoming fluent in Cantonese, everyone in England vividly remembering the exact last words spoken by a terminal patient from New Zealand, or all the people in a village suddenly knowing the combination for the mayor's safe. Any such events will be impossible to reproduce in a lab, but if they happen repeatedly and consistently enough, that could encourage the scientific community to seriously consider the brain/soul theory. ## A new discovery sheds light on the nature of the soul * A new recreational drug causes users in close proximity to become completely synchronized for a while. This effect can be reproduced consistently even if test subjects are separated to different rooms immediately after taking the drug. * A new technology has a consistent but unexpected side effect which "broadcast" one person's brain/soul signal to everybody in range4. * If the souls are "tethered" to Earth, then attempts to fly humans into deep space, would uncover a mysterious "lag" between body and mind - as very large distances will affect the soul/brain communication speed. * Just as X-ray imaging opened up a new way to examine the body, some new discovery could somehow detect/record the soul/brain communication - even if each soul has a different "protocol" so you can't transplant memories or thoughts, those could be "replayed" to the origin person (making him reexperience recorded brain transmissions, or causing his body to repeat recorded soul transmissions)5. * An artificial receiver is unintentionally invented - an experimental medical procedure for neurological issues, a new type of computer hardware (quantum computers?) or a new type of remote controlled machines uncover a surprising ability for brains to control equipment - investigation into the underlying principles make it clear that somehow the instructions are broadcasted from somewhere, leading to the discovery that similar principles explain the way the brain works - better than the existing theory that leaves the soul out of the model. --- 1: Of course, individual scientists may hold any sort of personal belief - but that's miles away from scientific consensus. 2: More accurately, a phenomenon / event which could convince the scientific community to start taking the idea of a soul seriously and research it further. I can't imagine any single observation which will prove anything beyond doubt, definitely nothing at the scale this question asks. 3: Or more horrifying results, depending on how that world soul-brain coupling works - I won't get into details since I find them unsettling, use your imagination. 4: There are four variants for this, depending on who is the broadcaster and which direction is broadcasted, and some or all of them could happen simultaneously - say that Alice touches the "handwavioum apparatus" and that affects Bob and Charlie either: 1. (A's brain to B&C souls) Bob and Charlie see through Alice's eyes (instead of or in addition to their own), they feel pain if she's hurt, hear what she's hearing etc. Later, they'll be able to accurately recall whatever Alice experienced - possibly having difficulties to differentiate those memories from their own. It's possible that during that time, Alice soul isn't receiving anything - she has no idea what's happening to body, and later she will remember "blacking out" while still being conscious (similar to "locked inside" syndrome). 2. (A's soul to B&C brains) When Alice tries to walk or raise a hand, Bob and Charlie do that (in addition to her or instead of her), they may feel like they are fighting their own bodies as even simple actions such as turning a doorknob become a struggle. Later, they will remember what happened to them. In this scenario, Alice's soul is not receiving anything from Bob and Charlie, so she's unaware that anything's amiss. 3. (B&C brains to A's soul) Like in (1.) above, Alice is receiving multiple sensory information - and it's conflicting even if the broadcast is suppressing her own brain's signals. 4. (B&C souls to A's brain) An inverted version of (2.) above, but worse - here Alice's body is getting conflicting signals from both Bob and Charlie, so even if her soul is blocked there's a control struggle - and her soul is still receiving so she is aware of it all. Bob and Charlie have no idea anything is wrong. All of these could be as comical or stressful as suits you, and will take completely different tones if Alice, Bob and Charlie were in the same room and in contact with each other when this effect starts. 5: After research advances enough, this could be useful in certain fields - e.g. forensics ("soul" fingerprints), law enforcement, athletics and performance. ]
[Question] [ It is common to find resource/loot crates in games that be opened/broken by the player to find money, ammo, resources, and similar. For instance, Warframe contains both loot crates that drop resources / ammo / credits: [![enter image description here](https://i.stack.imgur.com/J6Any.jpg)](https://i.stack.imgur.com/J6Any.jpg) and lockers which drop the same contents: [![enter image description here](https://i.stack.imgur.com/mqthg.jpg)](https://i.stack.imgur.com/mqthg.jpg) These can be found in other games such as: * Metroid: crates with energy (health) and ammo * Dead Space: crates and lockers with health, ammo, and money * Nioh: destructible wooden crates / etc with gold and ammo For gameplay purposes these are meant to supply the player with resources they need, but from a worldbuilding perspective they don't seem particularly realistic. Why would anyone put these items in unmarked crates / lockers? Wouldn't ammo be in ammo crates so it's clear what the container contains rather than necessitating scrounging through a bunch of random containers? And why would these be littered throughout the world instead of in storage? Military outposts and research facilities don't just leave random crates of lithium and whatnot throughout the building, right? And is there a reason it would be common to put physical currency in these crates in sci-fi worlds like Warframe and Dead Space? The Defense Logistics Agency's ["Supply Standards and Procedures"](https://www.dla.mil/HQ/InformationOperations/DLMS/elibrary/manuals/v2/) describes a meticulous management of supplies and resources with inventory checks and requisition forms, so I find it difficult to believe that resource crates in these games should be littered throughout the world as opposed to lockup where they could be inventoried & access to the resources could be more easily controlled. There are also numerous [OSHA guidelines](https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=10673&p_table=STANDARDS) on material storage like which materials cannot be stored together, flammable material storage restrictions, etc, and this is violated in so many ways by randomly dumping resources in resource crates littered throughout facilities in the game world. Even if there is no regard for human safety in these games, there is still value in proper storage to prevent your hard-earned materials from being ruined or destroyed on accident. Is there any reason some real world entity might store resources / ammo / physical currency in random , unmarked containers littered throughout facilities like this were they put into one of these games? I am looking to answer this for a particular game I am working on, but would like an answer not specific to a select world for any other games I may work on in the future. Ideally justifications for this sort of logistics would be realistic & practical, with no magic and minimal hand-waving (e.g. material safety is no longer necessary due to some unobtanium container that locks materials in a stable state). Simple, fundamental answers that transcend medieval, modern, and sci-fi use cases are preferred, but sci-fi specific justifications are acceptable (but should apply to all sorts of environments: space frigates, planetary research facilities, orbital stations, etc). The context is industrial, military, and research facilities rather than schools, shops, residential homes and similar. [Answer] ## THERE'S A WAR ON, SOLDIER: Item distribution in games does follow a certain logic, although don't obsess too much, there's always an imaginary reason. I think back to Unreal II, and how your character is being dropped supplies by government forces relying on you to do the dirty work. All these supply crates are placed for various reasons, and in good game design, each should be found in a semi-reasonable place. * Supply rooms: You would logically have separate rooms with supplies needed in a violent situation. Often in these games, they are accessible only after finding secrets/obtaining keys/possessing special abilities. * Secrets: Everyone with something valuable doesn't want to lose it, so these resources are squirreled away in ducts, abandoned tunnels, etc "where no one will ever find it." * Random items: These are violent games, and a little imagination tells you people dropped stuff as they ran/were eaten/died & despawned (we need to respect some game logic, too). * Distribution: Things went bad in a hurry, and supplies may have been in transit when the balloon went up. Good game design has these things in uniform piles, on trains, on forklifts, etc. * Supply stashes: Your fellow survivors would logically be gathering up all the stuff THEY needed to survive, and would have placed it in whatever containers were available. The less realistic scenario is that YOUR character can haul around tons of stuff and isn't themselves leaving caches of supplies in convenient locations in case they come back, or even for their fellow survivors. If you found a bunch of medkits and knew there were other survivors, and you couldn't drag them all around with you, would you leave them out for others to find? * Chaos: There's bad stuff going down, REALLY bad stuff. Logistics is one of the hardest things in a war, often harder than the fighting. An army marches on it's stomach, or in this case ammo packs and medkits. Military forces will drop supplies from airplanes hoping they'll land somewhere their own forces can find them. Then there's just the "What happened here?" moments where you have no idea how a particular situation happened to lead to something. There's a war on, soldier. Pick up the medkit and keep moving. [Answer] Putting everything in one place leaves you too vulnerable to infiltration and having your supplies stolen. Remember how stealthy you can be in games like Warframe and how it’s never really an issue to get into the enemy ship or station or whatever. Here, the enemy has accepted that they cannot run an airtight operation. Infiltration is an everyday issue and the most you can do is try to mitigate it and put it harder for the protagonist to mess with your plans. That means you can’t put everything in one spot, it’d be too easy for someone to break in take all the ammo you’ll need for your invasion or all the resources for your experiments And leave with it. Scattering important materials and ammo al over the place ensures that for any meaningful disruption on that area, a protagonist would have to run around through the whole facility. Which, while not impossible, is more time consuming and it’s also something you are already trying to stop. Since at that point, what’s stopping them from leaving a charge of your energy core on their way out. Finally, protagonists are also drawn to supply caches, these being often side objectives. Put a lot of valuables in one place and they are likely to loot it on their way out from hacking into your computer, freeing some prisoners, assassinating some key figure, etc. Not only this but they always seem to know about these caches somehow. Maybe they have a way to detect them or there are leaks within your organization or you are being hacked or who knows. Bottom line is lots of goodies in one place = an eager and capable hotshot trying to steal them. [Answer] Rather than purposeful caches, loot should be taken from the fallen. You are right that storage crates containing weapons would not be sitting on the floor of the subway. I suspect that this is done in games for ease of programming and homogeneity. The game writers do not want scrounging for supplies to be a distracting task. People playing these games want to fight monsters and find their way thru the maze. That is fine. In a realistic environment there are some places one would expect to find lots of supplies - medical bays, canteens, armories etc. If you are striving for realism, supplies in between should make sense. For example an empty dorm room might have snacks and a first aid kit. A dead person or dropped backpack could have the same sorts of supplies your character is carrying. A cushman cart or dolly might have supplies that were being ferried from one site to another and then abandoned. I can see doing it this way if scrounging for supplies is part of the fun, and there is no reason that it shouldn't be. [Answer] People eventually become complacent Sure, maybe when your military base is first built, everyone follows proper procedure for storing ammunition. But 10+ years down the line, it's possible that those procedures have been bypassed or ignored. Why bother spending an hour filing out the paperwork to request ammunition from the secure storage when you can just keep some in your personal locker? Besides, nothing bad has happened here before, it isn't likely to happen right now. Furthermore, during times of chaos, many security protocols will just get bypassed in favor of urgency. The soldiers need ammunition now and it takes too long to transport boxes of shells from secure storage to where they are every time they're running low. This can lead to supplies being stored insecurely and getting lost during the confusion. [Answer] The short answer is NO. There is no real-world justification for the common game design practice of scattering resources in random unmarked containers. The reason is that the motives of game designers who practice it are completely unrelated to the goals of real-world logistics operations. The topic of "loot boxes" in all of their various forms is among the most criticized, controversial, and cliched of all of the studied game design patterns. Pedantically in game design theory, they are a form of pick-up. Quoting the book Patterns in Game Design ([https://www.amazon.com/Patterns-Game-Design-Development/dp/1584503548/ref=sr\_1\_3](https://rads.stackoverflow.com/amzn/click/com/1584503548)) > > Pick-Ups are game elements that exist in the game world and can be collected by players, usually by moving an avatar or Units in contact with the Pick-Up. > Common examples of Pick-Ups include weapons, ammunition, and health packs in first-person shooters; money and energy in platform games; and food, wood, money, and metals in real-time strategy games. > > > Furthermore, > > As Resources that exist in the game world, the design of Pick-Ups is linked to the design of Resource Locations, and the design choices available for the locations have to be considered in parallel with those of the Pick-Ups. > > > It is in the design of Resource Locations where the principles of game design and real-world logistics design diverge. In typical game designs, the locations of map-specific pick-ups are not actually "random" but rather strategically pre-determined within some locality to provide players with incentives to occupy those areas of the map for some gameplay purpose. It may be to concentrate or scatter populations, to progress a story narrative, to force consumption or exchanging of other resources, or for any number of other reasons. Frequently, they are arranged to be goals of conflict in order to introduce inefficiencies in the supply of vital resources, increasing challenge and jeopardy in gameplay. This is very different than the principles of real-world logistics, where it is a goal to concentrate resources in locations that provide maximum efficiency of access with minimum cost (challenge) and jeopardy. This would be especially important for access to wartime materials during periods of conflict when supply chains might be simultaneously overtaxed and disrupted. In other words, game designers are motivated to use resource locations in ways to introduce inefficiencies in supply chains, whereas real-world logistics planners are motivated to use them to minimize inefficiencies in supply chains. For this reason, I don't think the two can be reconciled in a way that is plausible from a real-world perspective. [Answer] I saw a great one in a sci-fi setting using an advanced enhanced performance armor. "Health" was energy shielding in armor, one you last "health" was lost is was the shield failing and the damage getting through the suit to you, killing you. health packs were just energy sources compatible with the armor. Just imagine raiding random power tools, vacuum cleaner, floor buffers, and ATV's in a setting were a single power source was common. reusable points might just be compatible wall outlets. The suit manufactured ammunition from metal for a coil-gun. So ammo box were just things made of the right materials, things containing high purity iron or copper in large amounts. Nitrates for explosive ammunition. A locker might contain maintenance equipment or supplies that were compatible, similarly a crate might be full of desk lamps with iron base, replacement batteries, or fertilizer for nitrates. This even allowed for good level design since the starting areas was the manufacturing and distribution area, thus well supplied with machines and power tools, and the more difficult areas were office locations where all such supplies were rare. [Answer] ## Blame the computer The video game world seems to be run by lunatics who want to blast away at each other for the most contrived reasons. Fairly realistic in that regard, come to think of it. But AI was programmed to expect a different sort of planet, one with intact vehicles, orderly deliveries, and above all, orders. What this means is that people blast away in space ships, bases, and bunkers without a care in the world for the AI team that has to pick up for it all. They diligently repair what they can, and stuff whatever they find in the nearest locker. If they need it somewhere (anywhere) they know exactly where it is. In the meanwhile ... they have no orders where to send it. All they do is get it to the nearest registered node and Await Customer Input. ]
[Question] [ In the "Legend" trilogy and its sequel "Rebel", author Marie Lu envisioned a far future where Antarctica is a superpower decades after the United States splintered into two separate countries. The cities are built inside climate-controlled domes and are described as being large enough to hold skyscrapers. After reading through the book series, I wonder how probable it would be to have Antarctica become an independent country (let's call it the Antarctic Republic) either today or in the near future. For the sake of ignoring the politics of claims, let's just say this country is located in Marie Byrd Land, which is not claimed by any country. What would their economy be? How likely would other countries trade with the AR? Would it be more practical to have the country live in one combined settlement or multiple? Most of all though, could Antarctica becoming a sovereign nation be possible? [Answer] In order to have a functioning society you ultimately need a reason to cooperate. Unfortunately, Antarctica doesn't have any of those in our timeline. The primary reason people live in Antarctica today is for scientific research. Antarctica is invaluable for science as a truly pristine wilderness, and its harsh climate gives it relatively unique biodiversity. For example, [Antarctic ice cores can show human influence in the environment over time by their lack of pollutants such as lead](https://www.nature.com/articles/srep05848). While science is invaluable, the science that comes out of Antarctica is not so valuable that it would support a society that constantly needs outside supplies to survive. The continent has no significant geological or natural resources to exploit (the most prominent are coal and oil), and even if it did those resources would be significantly harder to access than the same resources found elsewhere on Earth. The only economic value that could be produced there would be the value its' citizens create, which again they could do anywhere else on Earth much easier. All that said, you could easily come up with some in-world reasons to settle Antarctica. Maybe you find a huge meteor strike that's rich in rare metals like platinum, palladium, or gold. Maybe Antarctica is shielded from the worst of the effects of global warming. Maybe there is a society there but they're just a subsistence society who wants to live "off the grid" rather than being a superpower. [Answer] Look at how all countries have become independent over time: * they started as a colony of another motherland * they managed to build up their economy * they managed to have an authority and enforce this authority decisions * the gained independence from the mother land Present Antarctica has reached the first stage, to a certain extent, with the various settlements used for research purposes. However the present climate prevents any attempt from building up an economy. All resources need to be supplied from outside, making the country utterly dependent from an external entity. If mining was allowed, the mined resources could be used to trade and slowly build up an internal supply chain: greenhouses for growing crops are the bare minimum you need if you want to be less dependent from foreign trade. However as long the climate stays the same the internal food production will be the weak point of the country. [Answer] To become an independent nation, Antarctica would need to be recognized by some number of existing nations, generally members of the United Nations. Prequisite to this would be that the aspirant nation have a self-sustaining population and have formed at least an interim government in order to petition the UN. Antarctica, at present, has no permanent residents (as far as I know) -- everyone on the continent is temporarily stationed there by some existing nation as part of a scientific outpost. While I can't say for certain that there has never been a birth on the continent, there certainly haven't been enough to claim a self-sustaining population. There has never, as far as I'm aware, been any attempt to form an government that would include the entire continent (nor even within an outpost -- such would likely be treated as mutiny by many of the outposts, which are managed by national military organizations). [Answer] Currently the [Antarctic treaty system](https://en.wikipedia.org/wiki/Antarctic_Treaty_System) keeps Antarctica from being claimed by any power on earth. Barred extreme circumstances, it's unlikely this will happen. However. (I've read those books too, they're cool). If everything in the world flips upside down and lot of people, nations or entire continents are fighting among each other as well as each other. What's keeping some people who want no part in the fighting of settling Antarctica? (Except for oppressive regimes keeping people from actually leaving the derelict countries they live in at this point). Surely this won't be easy. It's inhospitable, cold and there is no day-night cycle other than the seasonal rising and setting of the sun. Which mean you'd have a birthday every antarctic day if you were to follow the polar day-cycle. These issue can be mitigated given sufficient technology and persistence of the people there. The most difficult thing would be food. There is hardly any accessible biomass available at Antarctica shy from a few hardy animal species living there, which would stave off hunger for a bit, only for the brave colonists to succumb to scurvy. All in all there are way better locations any sort of society might spring into existence, and if colonists were to settle Antarctica they will have to solve some energy and food issues, or have a damn good idea how to solve this once there. Their community, plans and futures would be inconceivable otherwise. [Answer] Zombie Armageddon. Antarctica cannot be reached by land, and the oceans separating it from other land masses are deep and impassable by zombies. Every person arriving is carefully screened for zombie infection and quarantined for a period, and uninvited ships approaching the coast are sunk by the strong military presence. The Antarctic military is comprised of units from many nations who have in common their realization that Antarctica would be a good refuge. [Answer] I agree with the challenges that the other answers have posited. I worked backward through time to see if I could come up with a reasonable explanation for how the Antarctic Republic came to be a sovereign state. This is my imagining. 1. Massive deposits of extremely rare, valuable, materials are located under the ice and within rocky mountains of Antarctic. Gold, diamonds, Deuterium, Helium-3, and more. 2. Economic superpowers, US, EU, Russian, Indian and Chinese, collectively known as the G5, rush to exploit the bonanza, each declaring historic, ethnic, and social claims to the Antarctic continent or regions of the continent. Decades, and centuries-old, grievances between the nations escalate the land grab to be military operations. Air, Land, and Sea units engage in limited combat. 3. The UN declares the Antarctic region a shared prosperity zone called the Antarctic Economic Region (AER), guaranteeing every nation of a share of the wealth contained in the AER. The G5 build the necessary infrastructure to exploit the AEC. Workforces made up of settlers, economic refugees from other countries, and prison inmates are shipped to AER and put to work extracting the vast wealth of the continent. A period of prosperity blooms for every citizen of the G5 -- guaranteed a share of the AER wealth by UN mandate. 4. Over a period of decades, the many settlements and mines of the AER become a strong community, with stronger ties to neighbouring facilities than to home nations. The communities try to build their own industries to supply food, clothing, and limited luxury goods, but are consistently suppressed by G5 overlords. The citizens of the AER live lives little better than wage slaves and view the UN and G5 as cruel overlords. They organize themselves to protest their treatment. 5. Disparate communities of Antarctic Economic Region file grievances with G5 oversight council governing AE. AEC rejects grievances, sighting cost and implicit social justice concerns with granting the petition. 6. Individual communities of AER combine militias to form Revolutionary Antarctic Warfighting Regulars (RAWR). Fighting breaks out immediately, and G5 security forces and overlords are killed, captured, or driven off the continent. 7. Under a UN mandate, forces of the G5 invade the Antarctic to suppress the insurgency. 8. RAWR defeats the G5 Expeditionary Forces at the Battle of Mount Erebus. 9. UN recognizes independent and sovereign Antarctic Republic. [Answer] Once Skipper, Kowalski, Rico and Private, reach Antarctica you can witness one of the deadliest war humans ever faced after 'Independence Day' in 1996. The war will result in the evacuation of humans from Antarctica and the formation of Antarctican government lead by President Skipper. [Answer] It would begin with a series of colonies that become a little too successful The US war of independence could be a partial template for this. The many countries with claims to Antarctica start making lots of money extracting resources from it (probably mining or fossil fuels) leading to permanent settlements. Eventually the permanent residents of these mining settlements (or whatever) feel mistreated and want to keep the profits of their own output, instead of just being a Hinterland for the ruling country. If the profits from resource extraction are high enough for the colony to support itself, it can achieve Independence. Economics would force the different colonies to unify, either before or after rebelling against their ruling countries. There's no point in the Australian colony rebelling to control their own oil prices if I can just buy it from the Norwegian colony instead and undercut them. They would harmonise prices to get a better deal from the rest of the world, followed by trade deals etc. until eventually unifying into a single country. [Answer] to start a country you need a motivation to get people to move, and you also need the conditions to be livable. We can solve both of these with reckless use of oil and other fossil fuels. As you should know climate change is caused by fossil fuels, and if we continue to use them we will heat the earth up a lot. Antarctica may be completely clear of ice, and allow a landscape hospitable to humans. That solves the livability problem, although what about the motivation? The answer, again, is oil. Antarctica is thought to contain an enormous amount of oil, and if this oil is still being used by the time Antarctica thaws then we will mine the hell out of it. Eventually the oil prospectors could decide that they should turn into a country and more people move in. This country starts of with a large amount of money from its oil and rises to become a superpower. ]
[Question] [ Question: I'm trying to determine how large (geographically) my city will have to be to accommodate for 1 million people. I have a city that was basically formed by the gods to be fertile land with a good climate for crops (there are all four seasons) and to look like this: [![Circular city with mountains to the north and a river running around it](https://i.stack.imgur.com/cPu2U.png)](https://i.stack.imgur.com/cPu2U.png) That's not exactly how the river runs around the city, but the basic idea is that the land spirals from the place where the river enters the city down to where it exits. The city is split by the river into 8 octants, each octant is almost completely identical to the others. In the middle is a huge palace where 8 rulers live, surrounding the palace is the octant "administration building" then immediately out from that is where other normal city buildings are (textile shops, hospitals, etc.). From there you get to people's dwellings. The dwellings can definitely be multi-story apartment-like buildings. They're very effective at building tall/strong glass buildings (their magic system helps with that and the tall palace is evidence of this). The dwellings are arranged so that the people who work in the center of the city first, then people who work further out second. Then you get to the second layer of normal city buildings (so there's an inner hospital and an outer hospital for each octant). Finally you get to a third set of dwellings for the people who work out in the fields (farm and livestock land) and forests which surround the city. Here are some useful bits of context: * This is a world for a fantasy novel where the gods shaped the land to be suitable for this. * The civilization is sitting somewhere around the 1800s in our own history as far as technological capabilities. * This city is optimized for efficiency, not citizen's enjoyment. So sports and things like that don't have a place here and therefore wont take up space. * They use the river to travel and transport goods throughout the city (as I mentioned, the drawing is imperfect because it doesn't really communicate how this works very well). * They build most things out of glass (they get the sand from huge sand dunes in the east), but they do use metal (mines in the north) and wood for some things. The trees are within the boundary of the river. * The city is completely self-sustaining. With the exception of mines that are out in the mountains to the north and sand dunes to the east (the entire city is built out of especially strong glass to enable the sun-powered magic), everything the people need to survive and thrive exists within the boundary of the river. * The people in the city also completely share resources. Everything comes to the administration buildings and is equally distributed. No "class" system. This means that everyone's homes will be the same size relative to the size of their families. So what I need to determine is what the diameter of the city would need to be to accommodate ~1 million people. How big would the fields need to be in relation to the dwellings etc. I need to know this so I can accurately describe how long it would take someone to travel from the palace to the outside of the city given various modes of transportation (walking, riding in a carriage, and riding on a barge on the river). Thanks! [Answer] I found this on farmland necessary to sustain some amount of people: [How many people can you feed per square-kilometer of farmland?](https://worldbuilding.stackexchange.com/questions/9582/how-many-people-can-you-feed-per-square-kilometer-of-farmland) so using conventional farming (no hydroponics, magic, or crazy stuff), you'd get around 2350 people per km2. Flip it around and that's about 425 km2 for a million people. Ok, then I looked up population density for one of the major US cities that I'm familiar with. About 3662 people / mi2 or 1400ish people / km2. That's about 715km2 for a million! This metric isn't ideal at all since medieval london was around 100 people/km2 which is a huge difference so you'll have to play around with this number. I read that ancient Rome (city of Rome) had around 1 million inhabitants so that might be a good reference as well So, 425 + 715 = 1140km2 which is a circle with a diameter of 38km or 24mi. That's probably a solid start to the problem. You'd probably have to also look up how many farmers you'd need per km2 to help estimate that layer. oh and the average human walking speed is about 3.1 mph so on a clear cross-cutting road, it'd take 8 hours to make it across with no breaks or obstacles. [Answer] In the picture you provided the fields seem to be enclosed by walls and thereby probably count towards the city size. Size with fields: 2312.32 km2 Size without fields: 312.32 km2 Why?: Fields: For the field size I used this [source](https://www.smallfootprintfamily.com/wp-content/uploads/backyard_farm.jpg); according to it, 4 people need 2 acres of land, which is about 8000 m2. This means 2000 m2 per person, times a million, gets us 2000 km2. Rest of the city: I used [London](https://en.wikipedia.org/wiki/19th-century_London) at the beginning of the 19th century (at that time it had a million in population) and encompassed 122 miles2 or 312.32 km2. [Answer] Without consideration for comfort and open space you can look at [the list](https://en.wikipedia.org/wiki/List_of_cities_by_population_density) and pick [Manila](https://en.wikipedia.org/wiki/Manila) as your model. The highest density city in the world at 119,600 per square mile, you'd need less than 10 square miles for your city of 1million. The thing to note is that Manila isn't really high rise. It's very densely packed low and medium rise with minimal open space. [Answer] Apartments or houses? Apartments are far more efficient when it comes to regards to their footprint. In the 1800, my guess is that the average household had about 4 to 5 people. Hence, you would need 200,000 to 250,000 housing units. Class system will greatly influence the floor space per each housing unit. My lowest class, get about 40m2 apartment, or a 400m2 plot of land for a house. My 'rich' get 2500m2 plots for their houses. My experimentation yielded that the housing 'efficiency' is between 65% to 75%, depending on class. What this means, is that for 100 poor houses (100 x 400m2 = 40,000m2), you would need an area of 61,540m2. Thad additional area is for your roads and streets. My previous research yielded that a loaf of bread needs 1m2 of field space. A cow and a calf need about 1ha of grazing space. A chicken would need only 4m2 of space. I hope this helps. ]
[Question] [ This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. I was having fun reading [this article about making cement on the moon](http://space.nss.org/settlement/nasa/spaceresvol3/cemncon1.htm) when I asked myself (and now you), is it possible to make a suitably high-compressive-strength cement on Mars? * Since concrete is simply cement with rocks in... I'm only asking about cement. * I'm assuming absolutely nothing other than the recipie can be brought with astronauts (piles of dirt and a bazzillion gallons of water being a bit heavy to lift off the Earth). * The construction site is on the equator. * The best answer will explain how locally home-grown cement can be made at the equator without laying thousands of miles of pipe (or any other impractical solution) from the poles to the construction site. * "Can it be done?" obviously depends on accessibility of materials. However, it's not posible (OK, it's not practical...) to bring an entire construction company to Mars. There are machinery limitaitons. Ignoring all the logistics: you have one [mini-excavator](https://d2uhsaoc6ysewq.cloudfront.net/23263/Mini-Excavators-Kobelco-SK45SRX-6E-10673158.jpg), one [bobcat earth mover](http://cdnmedia.endeavorsuite.com/images/organizations/9d499d81-aea2-4810-be0b-ef77092d59bb/inventory/2425021/IMG_3836.jpg), some kind of big spinning tub to mix the cement, drilling equipment suitable for tunnel work, and a reasonable amount of handheld machinery. All suitably modified to work on Mars. I don't want to worry about the specifics on this point (don't quibble about fuel, etc.), it's not the focus of the question. Assume the equipment works, but you don't have the ability to bring anything and everything you might want. * Other than I'm ignoring our actual lack of present ability to get a ship to Mars — assume current technology. * And just to keep the minimalist answers at bay, I'm asking for hard science. Are all the materials accessible and can they be be successfully assembled? [Answer] Let's get empirical. The good news is research into [martian concrete](https://cen.acs.org/articles/96/i1/build-settlements-Mars-ll-need.html) has been done. > > Researchers think regolith on Mars could serve as a replacement for concrete components. The Mars rovers have used gas chromatography, mass spectrometry, and laser spectrometry to determine the composition of martian soil. Mars regolith is mostly silicon dioxide and ferric oxide, with a fair amount of aluminum oxide, calcium oxide, and sulfur oxide. The composition varies from place to place on the planet’s surface because of variability in asteroid collisions and the weathering by wind and water, in ancient oceans and in some modern water flows. But no spacecraft has returned to Earth with actual samples of the material. > > > But will it be easy? Perhaps not. There's a lack of water. On Earth, concrete cures and strengthens thanks to the chemistry of cement, which consists of limestone and water. However, most limestone on Earth was formed by sea creatures, which Mars never had. Martian soil has the calcium and carbon found in limestone, but the elements are scattered around the planet. And Mars has water but it’s not plentiful. “It’s going to be a long time before we can produce cement on another planet,” says Gianluca Cusatis, a professor of civil and environmental engineering at Northwestern University. However, sulpur can be used as an alternative. > > What Mars does have is a lot of sulfur in its soil, and molten sulfur has been used to bind some concrete on Earth. To test the possibility of using it to make martian concrete, Lin Wan-Wendner, while a Ph.D. student in Cusatis’s lab, melted sulfur and mixed it with JSC Mars-1a in a ratio of 1:3, the same recipe used for sulfur concrete on Earth. She then subjected the concrete to standard tests of its strength under compression, bending, and splitting. > > > Using Earth sand, that recipe produces a compression strength of about 30 megapascals, similar to that of cement-based concrete. But the simulated martian concrete was much weaker, which may have been because the material was more porous than the Earth version, Cusatis says. More porous concrete is usually a result of larger particles in the sand. > > > Fortunately, this problem of weaker sulpur-based concrete can be overcome. > > When Wan-Wendner, now a researcher at the University of Natural Resources & Life Sciences, Vienna, and colleagues tried a sulfur-to-sand mix of 1:1 and compressed the mixture to break down grains and drive out air bubbles, the resulting concrete had a strength of 60 MPa, twice as strong as standard concrete. Sulfur-based concrete also hardens quickly, in the time it takes for the mixture to cool. Regular concrete takes 28 days to completely cure and gain its full strength. The quick setting may be an advantage for 3-D printing, Cusatis says, because it means each layer of the material will almost immediately be strong enough to hold the layer printed on top of it. > > > This isn't the only way to make martian concrete. > > Another proposal for martian building materials eliminates a binder altogether. UCSD’S Qiao discovered that he could turn a regolith simulant into bricks by simply compressing the material rapidly. The soil is full of iron oxide and oxyhydroxide particles about 25–45 μm across. “If you compress the soil grains at high enough pressure, you are going to cleave those iron oxide nanoparticles,” Qiao says. > > > The reason for this stronger martian concrete is considered to be: > > The breakage gives the nanoparticles clean, flat surfaces. Under further pressure, they rotate so that the tiny, freshly cleaved facets press against each other and form a bond. Qiao believes the nanoparticles bind to each other through a mix of van der Waals forces and atomic bonds, though he hasn’t tested that assumption. What’s more, the binding happens in just about a millisecond under 400 MPa of pressure. That is about the same amount of pressure produced by dropping a hammer on the soil, Qiao says. And that is essentially what his team did. > > > Similar processing can be used on other forms of martian soil too. > > Another type of soil common on Mars is a sedimentary, claylike material formed in ancient oceans. It has the same chemical composition as other regolith, but weathering by water long ago means it has a fine-grained structure with no nanoparticles and an electrostatic surface charge. Qiao found that compacting layers of a replica of this dry Mars clay under high pressure also created a solid material. The layers of the clay became naturally aligned under pressure so that electrostatic forces held them together. But rather than striking the material rapidly, the researchers slowly squeezed the clay layers together. The two soils produce “similar strong solids,” Qiao says. > > > Other methods for making concrete have been considered. This involves 3D printing techniques. > > In Mueller’s lab at NASA, researchers are testing polymers as a binder for the regolith. It should be possible to manufacture polymers, such as high-density polyethylene, on Mars using carbon dioxide from the atmosphere and hydrogen from water in the soil, Mueller says. With a 3-D printer, his lab built a dome 1 m in diameter out of their simulated Mars concrete to show what they hope to do on a larger scale. Of course, 3-D printing with concrete is challenging, Mueller says. The deposited material has to be thick enough to hold its shape during the printing process but thin enough that it doesn’t clog the machine or dry so fast that it cracks. “The trick is getting a material that has the right consistency so that it can be extruded and it can cure,” he says. > > > Mueller would like eventually to skip the polymer binder and instead harden the soil by sintering it—that is, heating and compressing it until it becomes solid. That should be possible using a laser beam, a solar concentrator, or a microwave system. But until researchers develop that technology, they’re using the polymer binder to test their 3-D-printing ideas. > > > In conclusion, there are number of possible proposed methods of making concrete on the planet Mars. Research has already been conducted. The results are promising. presumably more research will be needed. There are questions about durability that may need to eb resolved. It is feasible concrete will be made from regolith on the Red Planet. As shown by preliminary research. EDIT: References: Neil Savage, "To build settlements on Mars, we’ll need materials chemistry," Chemical & Engineering News, Volume 96, Issue 1, pp. 16-18. (Issue Date: January 1, 2018 ; Web Date: December 27, 2017). Lin Wana, Roman Wendner b, Gianluca Cusatis, "A novel material for in situ construction on Mars: experiments and numerical simulations," Construction and Building Materials, Volume 120 (2016) pp. 222–231. Nilesh Biswal, Rushikesh Badnakhe, Sanket Sawarkar, "Construction Material on Mars," International Journal for Scientific Research & Development, Volume 5, Issue 10, 2017 [Answer] It is likely possible, but water availability would be the limiting factor. The article you linked already shows that the elemental constituents of cement are mainly Oxygen, Silicon, Iron, Calcium, and Aluminum... which are the most abundant elements in the Lunar regolith by a wide margin. Assuming that the rock formations near your lunar base are chemically similar to the rocks we process for concrete here on Earth, processing all the silicates, aluminates, and ferrites into Portland cement should not be a significant difficulty. The biggest difficulty would be sourcing enough water to mix with all that Portland cement, aggregate, and sand to make concrete. The article you mentioned states that there is approximately 1kg worth of water per cubic-meter of lunar soil (presumably this means about ~111g worth of hydrogen per cubic-meter, since oxygen is overabundant). This scarcity would mean that you'd have to process vast amounts of lunar soil for the water needed to mix into your concrete. You're probably better off just sintering/melting the regolith to make construction materials. The scarcity of water would be a huge limiting factor for your construction plans. Furthermore, the need for water for biological functions would likely make it far more valuable for those applications, and thus price it out of being a viable commodity for basic construction needs. Solar power is relatively abundant and limited only by the efficiency and square footage of the panels (and collection mirrors) you were able to transport. The same thermal processes you need to liberate that ~1kg of water from each cubic-meter of regolith can be tweaked to output other useful elements/compounds if you have enough energy at your disposal. That same cubic-meter of soil should provide about ~315kg of elemental Silicon, ~150kg of Iron, and ~90kg of Aluminum. With that in mind, there are myriad ways to create other high-compression-strength materials when water availability drives cost/strength ratios away from typical Earth-market-optimal solutions. For example, various glasses could be formulated from the available SiO2, Na2O, and CaO (though many Earth-typical glasses which use Na2CO3 would be production-limited by carbon availability on the moon). Fuzed quartz (which is essentially an amorphous glass made purely of SiO2) has a compressive strength of ~1.1GPa, which is much stronger than the ~20-40 MPa compressive strength of typical concretes. Basically, glasses and ceramics (in addition to metals and alloys) are likely to be the construction materials of choice on the Lunar surface. --- EDIT: The OP reminded me that their question was actually about applying the linked Lunar-concrete article toward producing Martian-concrete. The Curiosity rover found Martian soil to be composed of roughly 2% water by weight, which would be approximately 30kg per cubic meter of martian soil - which is a SIGNIFICANT boon compared to Lunar soil water. Martian solar energy collection would also have roughly 0.3-0.5 the output power of similar panels placed on the Moon due to the way solar energy scales with increasing distance, making the energy for "just melt everything" roughly 2-3 times as expensive on Mars compared to the Moon. As energy costs rise, and water costs fall, things will tend toward more and more Earth-like cost/benefit analyses. Whether that means hydraulic cement becomes large-scale more economically feasible than other water-less ceramics would require more research, but Portland cement production and use on Mars definitely seems more feasible there compared to the Lunar cement article you linked. [Answer] ## Forget cement the key is dedicated Martian concrete. [![enter image description here](https://i.stack.imgur.com/L5NI1.png)](https://i.stack.imgur.com/L5NI1.png) Mars is the most habitable planet in the solar system after Earth. In recent years, many countries, including the U.S., China, and Russia, announced to launch manned Mars missions in the next decades. Due to the dry environment on Mars, sulfur concrete concept is a superior choice for building a human village on the red planet. Studies of Martian meteorites suggest elevated sulfur concentrations in the interior. "At Northwestern University. These guys [2] have worked out how to make Martian concrete using materials that are widely available on Mars. And, crucially this concrete can be formed without using water, which will be a precious resource on the red planet." ## How "The key material in a Martian construction boom will be sulphur, says the Northwestern team. The basic idea is to heat sulphur to about 240 °C so that it becomes liquid, mix it with Martian soil, which acts as an aggregate, and then let it cool. The sulphur solidifies, binding the aggregate and creating concrete." Problems "in the 1970s, materials scientists studied the possibility of using sulphur concrete to build lunar bases on the moon. They quickly discovered that in a vacuum, sulphur sublimates—it turns from a solid directly into a gas. So any sulphur concrete on the moon would quickly disappear into the ether." ## Tests with Martian simulants "They used simulated Martian soil consisting mainly of silicon dioxide and aluminium oxide with other components such as iron oxide, titanium dioxide, and so on. They also tested various different sizes of particles in this aggregate." “The best mix for producing Martian concrete is 50 percent sulphur and 50 percent Martian soil with maximum aggregate size of 1 mm,” they say. And it is strong stuff, reaching a compressive strength in excess of 50 MPa, particularly if it is compressed during curing to reduce the formation of voids. Stronger than standard earth concrete. Bonus "the atmospheric conditions on Mars are suitable for this stuff. “Both the atmospheric pressure and temperature range on Mars are adequate for hosting sulphur concrete structures,” Martian concrete can be recycled by heating it, so that the sulphur melts. So it can be re-used repeatedly. It is also fast-setting, relatively easy to handle and extremely cheap compared to materials brought from Earth. All we need now are a new generation of Martian architects to design buildings made of Martian concrete that will be suitable structures for humans to live and work in. Plagiarised extract from [Technology Review](https://www.technologyreview.com/s/545216/materials-scientists-make-martian-concrete/) [2] For the full report by Lin Wan, Roman Wendner & Gianluca Cusatis click the following link [A Novel Material for In Situ Construction on Mars: Experiments and Numerical Simulations](http://arxiv.org/pdf/1512.05461v1.pdf) [Answer] Looking at the other answers, it seems concrete as we understand it is going to be difficult due to lack of water and limestone. I will suggest a few alternatives. 1. Rammed Earth construction. This is likely the least expensive option, and simply involves shovelling earth into forms which are then compressed by powerful hydraulic rams or an electrically powered equivalent. The rammed Earth blocks can then be stacked or otherwise used much like normal cinder blocks. They are inexpensive, sturdy, thick enough to provide radiation protection and can be made air tight by spraying the inner surface of a finished structure with some sort of sealant. 2. Sintered material. Much like rammed earth, but adding heat to essentially "weld" the grains together more securely. This will be stronger, but still likely to require some sort of sealant to maintain air tightness inside. Alternatively, you could build a rammed or sintered earth construction around a landed spacecraft, landing module (such as depicted in "The Martian") or even a pressurized balloon (protecting it from atmospheric abrasion, solar and other radiation and even temperature extremes. 3. Melted material/glass. This is much more energy intensive, but quite possible if you have lots of energy such as a nuclear reactor or giant solar mirrors. Glass blocks can be used as construction material, or alternatively heat energy can be applied to a structure made of rammed or sintered earth to turn the outer layer to glass. This makes the structure much more air tight (although there is always the possibility of cracks in the glass being weak points for air loss. Glass is also a brittle material, so backing the glass with rammed earth may provide much more security by having a "soft" backing layer. No numbers are provided since the materials making up Martian dirt are not known well enough to make any accurate calculations. Rammed earth blocks could be used for an interesting construction: a trench could be dug and the spoil used to make rammed earth blocks. The blocks are used to form a barrel vault in the trench and the structure is backfilled to cover the arch and provide the compressive force to give the structure maximum strength. Once the interior is sealed, lights added etc, a fairly pleasant environment could be created. [![enter image description here](https://i.stack.imgur.com/8zE3N.png)](https://i.stack.imgur.com/8zE3N.png) If you imagine the blocks surrounding the vault to be earth instead you get the idea ]
[Question] [ Hydrogen and oxygen gases can be combined to form water and a lot of heat. As with many exothermic reactions, the heat from this process can provide activation energy to the reaction of more H2 with more O2 in a runaway process commonly referred to as an explosion. I would like an atmosphere rich in both hydrogen and oxygen gases, but I don’t want it to explode. Well, I don’t want it to explode too much. Weather systems creating pockets of high pressure that spontaneously ignite, or lightning strikes resulting in exploding pockets of atmosphere sound awesome. What I need to avoid are planet-consuming runaway explosions that spectacularly scour the surface of the world of all life. A second consideration is that I would like this atmosphere to be breathable by humans. How much hydrogen and oxygen can coexist in the atmosphere before apocalyptic runaway combustion becomes a possibility? My current explanation for this world is that a biological or geological process constantly emits large amounts of hydrogen into the atmosphere but that constant small fires and explosions prevent it from accumulating to more dangerous levels. I’m trying to determine what level that is, where explosions are happening but there isn't a risk of extinction level events. [Answer] # The explosive range for Hydrogen is 4% to 75% This is really a question about stoichiometry. If your planet's air (without the Hydrogen) is roughly the same as the earth, then Hydrogen will start to burn (given an appropriate ignition source) at 4% Hydrogen by volume. If you get above 75%, then it's actually the oxygen you won't have enough of and you won't be able to burn again. What we're talking about here is called the lower and upper explosive limits for a given gas, in this case Hydrogen. The most explosive concentration is at about 35% hydrogen, this is when there is exactly twice the amount of hydrogen as there is oxygen, so neither of their concentrations are limiting. The reason it's not 42% (twice the 21% oxygen in air) is because the hydrogen displaces both the oxygen and the nitrogen. It is worth noting that as you get closer to the 35% concentration that the explosion will progress from what just looks like a fire (whooshing flames) to a much more potent, almost instantaneous explosion (like a pop or a bang). [Answer] Gaseous molecular hydrogen doesn't stick around; it escapes into space. The places where it doesn't do so are places with substantially more gravity than Earth (eg. gas giants). The hydrogen that doesn't escape will react, but (for the most part) non-explosively, because hydrogen and oxygen will, left to their own devices, settle like oil and water, with the hydrogen in the upper atmosphere, either escaping, or undergoing UV excitation which breaks the hydrogen into atomic hydrogen, which will react with just about anything to form hydrides or salts. If you had a uniform distribution of, say, 20% hydrogen by volume across the planet, then yes, a single spark would trigger a cataclysmic exothermic reaction. It would be loud. But there's no way such a distribution could remain mixed for any substantial period of time, and you'd need to continuously produce enormous quantities of hydrogen (assuming your planet is earthlike). ]
[Question] [ I just spotted this [article about a metal foam that stops armor-piercing bullets as well as radiation](http://www.gizmag.com/metal-foam-bullets/42731/). It's a press article, not a scholarly paper, so it may be complete bunk. And rifle bullets are amazingly slow relative to just about any object wandering around in orbit. However, metal foam seems like something that could be "easily" manufactured in a Lunar environment. Is making a habitat shell out of material like this going to be significantly helpful, or are meteorites just going to punch through it anyway? [Answer] It would work, but would also need constant repairs. The basis of the armor mentioned in your attached article is not simply to stop the bullet with a metal foam, but to use the metal foam as the middle layer in a new form of composite armor plating, in which an outer layer breaks up the bullet and distributes shock, a middle layer absorbs kinetic energy, and a third layer prevents passage of the projectile. In this configuration, the foam layer offers better energy dissipation and better protection than a simple layer of solid metal. A similar set up could be used to armor a lunar base, though you'd need significantly thicker armor to stop an asteroid. However, your armor will take significant damage whenever a projectile hits it. Meteors have lots of kinetic energy, and the method of energy absorption in most such compounds is through mechanical deformation, a.k.a. damage. As even small meteors hit your shielding, it will slowly break down and become useless, requiring constant repairs to maintain effectiveness. [Answer] You probably need metal foam as a form of "spacer" in a series of spaced armor plates. although most people tend to use kevlar to stuff spaced armor gaps. The hard plates would deform the incoming projectile as it passes through and the metal foam absorbs the fragments. <https://en.wikipedia.org/wiki/Spaced_armour> <https://en.wikipedia.org/wiki/Whipple_shield> [Answer] As the technology is not really proven I think any answer would be primarily opinion based. You might build your base out of a certain material and then armor it with this sort of shielding. However, when considering any sort of shielding you have to also consider the mass and acceleration of the object impacting it. Basically, if a meteor the size of a house impacts your base no amount of foam is going to save it. By far the easiest approach is to simply build the base underground. That way the surface of the moon is your "shield". [Answer] It could be workable but the layered shell technology they tested for next generation spacesuits works better and requires both less metal and less maintenance so foam is probably not going to be the go-to unless the metal being used is a waste product, or otherwise exceedingly cheap, and the location is a stationary base that doesn't have to consider mass too carefully. ]
[Question] [ The Story Numenera puts you as someone living in the Ninth World (actually the ninth Civilization that currently inhabits Earth) All eight former Civilizations were somewhere between Type I and Type II on the Kardashev scale as far as I can tell. They must have developed at least interstellar Travel(probably not FTL) because they left behind some alien species that they brought home from other planets. The Question What would be the limiting factors of an earth like planet supporting this rise and fall of Civilizations with high technological level on the same planet given the natural limitation of resources. Clarification 1. Those Civilizations never exist at the same time, they develop and after a while descend into some kind of medieval world before they slowly rise again, loosing every bit of knowledge in between 2. It is not known what caused the Civilizations to descend again. 3. The timescale for would be one billion years between the rise of the first Civilization and the beginning of the ninth. But feel free to give examples of different timescales to show what limits there are. [Answer] I think, in terms of a literary solution anyway, the previous civilization should have effects that are specifically enabling to the existence of the new one, to cancel out the disabling effects. Our own civilization could not be replayed again, but instead something else will be made possible. Accessible oil and coal will be gone, at least for a fraction of a billion years. But early civilization will find aluminum in metallic form and find that easier than isolating bronze from ore. The strata associated with the [anthropocene epoch](https://en.wikipedia.org/wiki/Anthropocene) will show an imprint of our presence, with new minerals bearing traces of man-made materials and processes requiring other such materials. Consider also the biological effects. Recovering from a mass extinction, the biosphere comes back better ans stronger than ever after 20 million years. There will be adaptive radiation to fill the empty niches, and this next time there will be domesticated species to serve as the starting point. Consider: in the age of dinosaurs plant life was poor in nutrition; fruit and grain did not exist. Now, squirrels have a niche to fill and cows can be adapted to eat grass. Our paleolithic ancestors had to spend generations making wheat, corn, potatoes, etc. come into existence. In the next cycle, some animals may have an easier time due to the very existence of more advanced foodstuffs, just as squirrels could not have existed before flowering plants and modern ruminate animals are far more efficient than any [ceratopsid](https://en.m.wikipedia.org/wiki/Ceratopsidae). Likewise, a rising civilization will have plants suitable for agriculture and animals that are easily domesticated. Finally, there may be caches of knowledge to aid development. Whether time capsules or arriving missionaries, they may learn important tips such as the importance of waste management and sterile bandages, which might have as large of an effect at the right stage as any advanced technology. [Answer] Some of this depends on the time frames you're dealing with. Are we talking a few thousand years? or 100,000s or millions? The longer the time frame the more likely it would happen. Even completely new species could evolve and have brand new source of coal and oil at the millions of years level. However at the 1000's one or two previous civilizations might be possible. Though at interstellar traveling, some semblance of the previous civs might still be out there, leaving the 'mother' planet as a backwater or 'used' up planet. What might cause a collapse is everyone who can got of the dying planet and those left where able to survive while the planet healed itself with the bulk of the populace gone. [Answer] Not sure why folks think that all of the natural resources will be used up. I assume that after the decline of one civilization, there are still trees around to make fire? If it takes a hundred million years for a civilization to rise and fall, then it is probably even possible for coal to be regenerated in some or many areas (it can be formed in tens of millions of years[1]). But much better than finding a coal seam would be finding an ancient landfill. When an archaeologist finds a midden today, the only interesting artifacts are bones and stones. But when an archaeologist 200 million years from now finds a midden, it will have high concentrations of rare earth metals useful for advanced electronics. Surely that is a nice jump-start for any new civilization! Not only that, but lots of uranium will be mined and concentrated as well (assuming it wasn't detonated or taken off-planet in ships). Uranium and thorium have half lives in the billions of years for some isotopes[2]. And if the civilizations care at all for the future, then they will leave knowledge lying about in a durable form (explored in Niven's Footfall, where knowledge was recorded on metal plates). The advancement of civilization pretty much depends directly on the amount of useful energy the inhabitants can harness. At prehistoric levels, only human power is meaningful. With agriculture and animal husbandry, draft power from animals becomes available and makes it feasible to farm large tracts of land (rather than just subsistence gardens). With fire and metallurgy, steam power eventually becomes available, first from wood and biomass, and later from coal and fossil fuels. But solar power can also be harnessed by dams, and was long before the Industrial Revolution. Again, if knowledge is passed down in some form to each new civilization, then converting power to electricity would greatly aid the reboot of the next civilization. That's because electricity is one of the easiest ways to convert power from one form to a more useful form. One electrification has been achieved, even the absence of fossil petroleum is not a major deal-breaker. Gasoline has one of the highest energy densities of any chemical fuel (non-nuclear). But ethanol is decent, and can be manufactured from average biomass. At sufficient technology level, gasoline and kerosene can be manufactured from scratch, via thermal depolymerization (TDP)[3]. Even steel is not a problem, because in thousands of years, most of the steel on earth will rust down to iron oxide. No tectonic activity necessary. But let's say that the previous civilization managed to coat most structural steel with really effective anti-rust coatings. No problem. Just chisel off the coatings and let it rust away! But most likely, no steel will be so thoroughly coated as to resist all weathering effects. Steel at the bottom of a lake or ocean will last longer, but will be harder to get at anyway. Unless a civ goes underwater to escape land, most of the steel will probably be on land. The Mote in God's Eye series also explores the theme of cyclic civilization (a good read!). [1] <http://www.planete-energies.com/en/medias/close/how-coal-formed-process-spanning-eras> [2] <https://en.wikipedia.org/wiki/Isotopes_of_thorium#Thorium-232> [3] <https://en.wikipedia.org/wiki/Thermal_depolymerization> [Answer] It's an interesting question - any civilisation following hot on the heels of ours would have a hard time extracting resources such as coal, metal, etc from the earth as all the immediately accessible resources have long been used up. However, instead of primary sources of say tin or iron-ore, a civilisation following our own would probably find recycling or scavenging resources from old dumps or ruins - especially metals. This might act as a barrier to later growth as it would be less obvious that these materials came out of mineral deposits found in the ground, as the richest sources of metals would instead be found in urbanised areas - without any link back to their original sources. [Answer] I understand it as wondering how civilization could restart so many times if each cycle uses up some of the natural resources. It could be possible, especially if some of those civilizations practiced conservatism, and/or brought back resources from off planet since they had some kind of interstellar transportation. Also, each civilization would be able to mine some of the junk left behind by previous civilizations for resources. IIRC this does happen some in Numenera lore? One thing that would help is that even with the fall in between, some of the knowledge would remain, making each rise a little easier, especially if advanced relics and texts can be found. Also, each civilization would adapt to make use of the resources available. So all the oil us used up by cycle 4? More research is put into solar or wind in cycle 5. So long as one cycle didn't permanently make the earth uninhabitable, life would find a way. Hardship can make people adapt pretty quick. Edit Limiting factors: A lot of stuff would renew over time. Metals aren't one of them and so the metals that are mined during each cycle wouldn't go back into the ground without some cataclysmic upheaval swallowing a scrap yard, but this might make some metals easier to find in purer forms. Metals such as aluminum will be more readily available earlier in a civilizations timeline than it would be normally. Aluminum is hugely abundant (8% of the crust), but does not occur in its metallic form anywhere naturally. It is not easy to produce, and for a while [was more "rare" and more valuable than gold](http://www.todayifoundout.com/index.php/2014/05/aluminium-cost-gold/). Aluminum turns into aluminum oxide when it corrodes, which protects the aluminum underneath from further corrosion. This would allow it to survive better. One metal that might be harder to find over time would be iron, as any iron that is mined and refined would tend to rust away over long periods of time exposed to the elements. To balance this out any civilization that can make it off planet is going to find a lot of iron (and other metals) in the asteroids to bring back to the planet, and so there is a better chance that some of it might remain for the next cycle to use until they can make it into space. Other materials will be developed as well, such as ceramics which could help bridge the resource gap. [Answer] It's kind of an interesting question for me, since I've given it some thought before and think it would be totally plausible. * This depends on what time scale you're having in mind. Having the real world examples of our time, the different nations could race for interstellar exploration and colonization, which I guess will lead to another world war and possibly crazy leaders or terrorists will tend to use H-bombs this time and ruin the mother planet for the current civilization and the colonies without the support of earth would soon fade away. After that give it a couple of million years and the ruined earth (with nuclear clouds and so many new mutations and possible left bacteria or even bugs) might give rise again to another civilization who have no idea about what happened before them and just could give some guesses. You could also consider that the course of evolution could change this time and a new specie (or more) could rule the earth, but the same cycle would happen for them again too sooner or later. ]
[Question] [ # Scenario: 20 people (men and women of varying demographics, occupations, and socio-economic classes) awake and find themselves on a deserted tropical island (with no idea of how they got there). The island is approximately two square miles and contains a freshwater river, trees and vegetation, and small game for hunting. The island is in a location such that they have literally no chance of being found/rescued but they, of course, do not know this. Upon coming to, they all circle around and attempt to discuss what the heck is going on, only to find that they all speak completely different languages(listed below)! It also just so happens that every single one of the 20 has no knowledge of any other language on the list (call it a coincidence if you want). ### The languages represented are: 1. English (US) 2. Mandarin 3. Hindi 4. Arabic (Standard) 5. Russian 6. Bengali 7. Malay 8. Japanese 9. Telugu 10. Korean 11. Turkish 12. Vietnamese 13. Yue 14. Kannada 15. Western Panjabi 16. Swahili 17. Brazilian Portuguese 18. Javanese 19. German 20. Fulfulde # Questions: ### Short Run: How do you move on in a group like this without the ability to communicate effectively? What is the best way to go about attaining the things necessary to survive (i.e. food, water, shelter etc.) without communication? ### Long Run: How long would it take for them to create a singular, unified method for communication? Would one of the languages gain dominance, or would the languages present morph together into a psuedo-island-language? Will future generations (theoretically) speak both languages of their parents? Bonus points for extra insight Alert me if I haven't provided enough detail into a certain aspect and I will update the question as promptly as I can! [Answer] ### A Pidgin Develops Give it some time and the group will end up speaking a common [pidgin](http://en.wikipedia.org/wiki/Pidgin) language, mashed up from various of their languages. People will be frustrated and lonely for quite a while, but new common vocabulary will spread quickly through the group. Some of it will be from words that were already common to several people in the group, but most of it will be from a mix of the different languages. ### There's an Aznat in the Camp Let's consider a single situation where some group members might want to work together without a common language: trying to deal with a problem that's somewhere around their campsite. One person notices something and cries out Aznat!. You're there (feeling as alone and lost as everyone else) and you hear them cry out, so you look to see what's going on. They keep saying aznat, aznat and some other things -- no one seems to understand, so they make hissing sounds and flick their tongue out, making slithering gestures with their hands, and pointing in the direction where they saw it. > > ![aznat!](https://i.stack.imgur.com/4K6jH.jpg) > > > Now let's say you happen to catch a glimpse out of the corner of your eye of something red and black slithering through the bushes nearby. You think it might be a snake, and you've got half a dozen people standing around who just figured out that there's a snake somewhere nearby. What's the fastest way you could say "snake" to all of them to enlist their help in your direction? Do you cry out the word in your language and go through the whole charade again? No. You'd say Aznat! and gesture to where you saw it. --- About ten years ago I was part of an exercise in learning someone else's language without any language in common. Coincidentally, we had about 20 people in that group as well. To this day I still know how to say a few phrases in the made-up language that we used. You'd be amazed how well you remember language that you learned under stress, or when it proved to be useful. Just be glad you didn't actually have to deal with an aznat while reading this post. [Answer] Nice selection! Closest is the Arabic borrowings in Swahili, maybe a little between x-over English & German. Mandarin provides a means of writing ideas that may be understood by literate Japanese and Korean. After that, everyone gives their words for sand, sea, coconut, &c, and starts communicating. It's what humans do, even if they play a lot of charades for the first month A lot will get done at first by someone gesturing "Come along" then showing what they think everyone needs to do. I doubt one language will dominate. They will develop a pidgin that all can use: positional structures, no tones, single vocabulary, no complex consonent groups. Look at all the traditional Pacific pidgins. Swahili began as a pidgin. Bonus vocabulary survival points to languages spoken by women: babies learn to speak from their mothers. Why no New World languages? Mayatec or Quechua, say. [Answer] Assuming they all understand the common goal of survival and realize that communication is necessary to survive, things get easier. Isolate the simplest phrases for the stuff around them, like water. In many languages, simple concepts sound simple and take one or two syllables at most. Not everybody will pick up all 20, but the more educated ones among the group (since there is a socioeconomic difference) will be able to pick up a few words from other languages, especially languages that are related. Chinese and Japanese writing systems overlap with hanzi/kanji. Korean old style writing system also has overlap with hanja, though modern Korean doesn't see that as much due to hangeul being prevalent. For example, the character for water is 水 in Chinese and Japanese. Not only that, but they sound very similar. Japanese have Chinese-based pronunciations in their language. Korean does as well. With the above example: * 水 in Mandarin: súi * 水 in Japanese: sui * 水 in Korean: su Japanese and Korean have their own native synonyms for water as well (mizu and mul, respectively), but they would understand what the above is. Others will be able to use writing to understand one another, or at least to say aloud what others write. Languages with Latin scripts can do this: * English * Vietnamese * Swahili * German What I can see happening is for there to be groups that band together based on similarity to each other. This is based on race and language, the assumption here being that the people speaking these languages match the majority ethnicity for that language, i.e. Arabs speaking Arabic. As there is overlap between ethnicity and language, you have the potential for divides to emerge. But in some cases, it may be based on scripts used for writing, assuming people are literate. It's not an impossible scenario for them to learn how to communicate beyond just grunts and facial expressions and hand gestures. They would be able to read and, eventually, speak, but likely only within small groups of associated languages. [Answer] The most straightforward approach that comes to mind would be in a manner similar to how our ancestors first developed languages, starting with pictograms. The hypothetical group would first establish symbols for things like trees or people, then perhaps move on to verbs such as 'give' or 'run' before approaching concepts like 'danger' or 'sadness.' As vocabulary builds, refinement of this language would lead to shorthand for the more complex symbols, leading to a system of glyphs that become increasingly divorced from their source's picture-like appearance. That being said, the unified system wouldn't take very long at all to establish. [Answer] The people in the group from majority-Muslim countries ought to be able to write or speak a little classical Arabic from the Koran and Muslim religious events. I make that the speakers of Arabic, Turkish, Malay, Fulfude and Javanese. I realise that you have specified that they are all monolingual, presumably as part of some sort of experiment to see how well humans cooperate, but all of them being entirely ignorant of Arabic would need specific explanation in order to keep up willing suspension of disbelief. I agree with earlier comments saying that other groups that might form would be those making use of Chinese script and those making use of Latin script. Add the Fulfulde speaker to the latter group. In fact practically all the people ought to have some familiarity with the Latin script. Despite all the above, I think that given that they do not know that they have been picked for monolingualism, the group as a whole would might well attempt to coalesce on speaking English. At present, although English is not the most widely spoken native language, it is by far the language that is spoken as a second language by most people on Earth. Each member of the group would obviously know that he or she couldn't speak it, but it would be a reasonable guess that several of the others would. A wrong guess, in this scenario, but they don't know that. [Answer] I agree with Joe. The people would focus on the practicalities of surviving and from the communications relevant to that a pidgin language would naturally form. Names for plants would come from the languages of the people knowledgeable about plants. Names for fish from people who recognize them. Or names would simply be made up. A small group of people in survival mode does not really need a common language, gestures, actions, and a simple pidgin would go a long way. Humans are quite good at guessing what others mean. In fact we are compulsive about making such guesses even when information we have is insufficient or incorrect. If people would be stuck there for long enough to have children, I assume a real language based on the pidgin would evolve. As others have noted, many people would recognize words loaned from "classical" languages such as latin, classical arabic or greek, sanskrit or mandarin. But I don't think people would have time or interest in trying to communicate based on that. They would have no need for sophisticated communication and high need to gather food, secure water supply and shelter. A situation there they'd have the idle time for language study is hard to imagine. [Answer] The answers so far have given a lot of good discussion about the specifics of individual languages. A few further observations: ### personality goes a long way Given that each language is represented by a single person, accidents of personality and linguistic facility will go a long way towards determining the makeup of the shared vocabulary. For example, let's say that: * The Turkish speaker is a horse trainer. She will be of necessity an alpha personality who does not hesitate to enforce dominance in any given situation, because that's how you prosper (and avoid getting kicked) when you are around horses. Turkish will be presented to the others in something of a "my way or the highway" fashion, reliably and repeatedly. * The English speaker is a philologist of Native American languages, who is not an assertive personality, but who is quite skilled at picking up a working knowledge of other tongues. He will naturally be interested in the languages of others; at the same time, he will not be predisposed to shout [domineering linguistic demands (NSFW)](https://www.youtube.com/watch?v=m_mDTLphIVY) at the rest. This imbalance will result in a much greater preponderance of Turkish than of English in whatever spoken language the islanders settle on. This example can be generalized. Some personality types are much more likely to enforce their vocabulary on the group. ### gestures will probably persist Given that gestures, facial expressions, and pantomime are the initial means of communication between people who are trying to survive, a fast-developing vocabulary of well-understood basic gestures is likely to be hammered in hard, and would probably prove too useful to discard, even when the spoken vocabulary is converging on a stable form. The likely result: a persistent mashup of spoken and gestural communication. Combining the two points, you have a generic template for the mode of communication that your castaways will adopt: common gestures and somewhat arbitrary multilingual spoken vocabulary. [Answer] As many here have said, sign language will prevail for some while, while another method of communication gets going. That said, with some extraneous signing to each other, they might be able to organise it so that each person teaches a few simple phrases in their language, such as: * "Help me." * "Need food/water/etc." * "Yes" and "no" (although those are easy in signs so maybe not so essential). The idea is that if more than one person has at least a basic level of understanding of each language, they may be able to facilitate communication. Unfortunately, it looks like these people won't get the chance to fully develop a new language - that takes hundreds to thousands of years, and they don't seem to have a [viable gene pool](http://genetics.thetech.org/ask/ask113) to sustain a society. However, discounting that, the language they eventually develop by miscommunications, signing, botched explanations, facial expressions, body language and all those factors will be one of the most diverse languages the world has ever seen, taking its influences from all these different places. [Answer] If these people are all trying to communication, I don't think the process would be particularly difficult. Tedious, but not difficult. They could surely teach each other nouns by pointing to objects and saying their word for it. Like, if I was trying to communicate and the other person pointed at a banana and said "frangbar", I'd take it that "frangbar" means "banana". Etc. Similarly one could mimic simple actions. like jump up and down and say your word for "jump". Etc. Once we'd established those we could start working on adjectives. Like take a big banana and a small banana and say "big banana" and "small banana", etc. Of course there would be ambiguities and mistakes, but you work through them. I'm reminded of a lecture I once heard from a missionary explaining how he learned the language of a previously unknown tribe. He mentioned that on one occasion he pointed to a hut and asked "what is that?", and the other person gave the word for "finger", because he thought he was holding up a finger rather than pointing at something. Etc. [Answer] I'd like to add to the (great) answers so far, based on the real life experience of being part of a multilingual group in several occasions. Common words While Joe's example would happen rather frequently in real life scenarios, I believe that the group will start using the most common / easiest to memorize or pronounce sounds from the collective vocabulary. With the help of miming and drawing, this could go a long way in a relatively short time, and I believe that a group with the prospect of a long term forced stay with each other will have at least one smart person in it who will make sure that some time is dedicated to building a common language. In this scenario I imagine this leader figure to be smart enough to try and form a vocabulary that everyone can pronounce easily enough. Using the example of the snake again, I imagine that in an alternative timeline where the word "aznat" hadn't been incorporated in the common language due to necessity, the group would gather together at some point of the day, possibly around lunch - snake stew? - and compare their terms for the creature... \[I am using the transliteration conventions I am used to, apologies if this creates confusion to anyone. Also, most translations are Google based, I cannot guarantee they are correct. ? mean that I couldn't find a translation for a \specific language.] snake (shé) साँप (Sām̐pa) ثعبان (tẖʿbạn) змея (zmeya) সর্প (Sarpa) -> to which the English-speaker might add "serpent" as an alternative term, happy to recognize a familiar sound ヘビ (Hebi) పాము (Pamu) 뱀 (Baem) yılan rắn ? ಹಾವು (Havu) ? nyoka serpente ula schlange ? Most likely after the first times, they won't go around all 20 people for each term, but rather try different languages until someone recognized a familiar sound, and then work from there. At this point I would expect the group to use a word starting with or including a sibilant sound, most likely ending up with either the Bengali term itself, or something like s\(r)p\ (my guess is serpe/selpe/sepe). This is somewhat similar to the process used for the creation of some artificial languages (I'm thinking about the semi-failed esperanto and europanto). Easy sounds While general sounds might be very similar, I expect this group to either 1) shift towards a more limited number of sounds than their own languages, limiting the new pidgin to sounds accessible to everyone's mouth, or 2) to include words that are pronounced somewhat differently by different people with groups of sounds that can be used alternatively without changing the meaning of the word. So in the example above I would expect the word for "snake" to be: 1) sepe (I am assuming here that all 20 people can pronounce the "s" sound in a manner that is common to everyone) 2) §e\pe (with § indicating s/sh/ts/..., and \ being either omitted or something close to r/l) While I believe case 2 to be initially more likely as it's simpler to agree on, with some attention to avoiding homophones, I would expect 1 to prevail in eventual future generations, or after a long period of time. Some members of the group will realize that others are not as accustomed to the large number of vowel sounds, therefore the community will shift towards the use of a reduced number of vowels, pronounced with some differences, but likely rather easy to distinguish as A, E, I, O, U. I don't think any of these languages has a more limited number of vowels or if their speakers would be likely unable to distinguish among these five. Tones as used in mandarin will likely be ignored after a short time, as those familiar with them should notice how others are almost entirely unreceptive to them. Very peculiar sounds - I am thinking clicks in the Khoisian languages as an example - might still be included in a simplified version that makes limited use of them, in short words. (...and letters?) With the number of possible phonemes being reduced, it will also be possible to settle on an alphabet common to all 20 members of the group. I believe that the chosen system will be the latin alphabet with possible modifications for extra sounds, being the most common within the group, and quite well suited for a language composed of simple sounds. It helps that most symbols are rather easy to discern and memorize, assuming uppercase letters being used. ...and some grammar While most people will tend to follow their own grammar, as words for people, animals, objects, actions, and so on are agreed upon, I would expect a simple necessity driven-based grammar to prevail at first. There would be no articles, the language would be mostly genderless, and singularity/plurality, gender, time, etc., would mostly be expressed through adjectives and adverbs. The fist word in sentences would be a vocative (to attract the attention of the intended receiver of the message), the general argument of the message, or the subject; especially at first sentences may begin with a series of terms gradually specifying the subject, e.g.: "about food, today, midday: we now berry many gather". Gestures Gestures will be very important at first, and while they won't be as necessary as time goes on, I expect the future of the group to look somewhat similar to communication in Italy: some concepts are expressed via sounds, some via gestures, often both go together. I will not elaborate further as Bill Blondeau already did so. People from cultures with a more rare use of gestures will pick up on what other members of the small community do. [Answer] With such differences in language families, picking up words may be a problem. I cannot distinguish the tones in Mandarin, for example. Differences in what part of the sound is significant can make it frustrating and impossible to pick up let alone repeat. You may end up with a situation where (only) the native English speaker can understand everyone's use of recently learned English words, because of the simplified phonetic structure caused by it being a (recent) language of immigrants. A New Yorker would be the best in that regard. I'm more worried about who you get to make dinner. OTOH, it might provide a larger base of knowing things that can be eaten. ]
[Question] [ Let's say you have some advanced aliens seeding life on multiple earth like worlds. They want sapient roughly humanoid creatures to evolve from this starting seed. However, they are not dropping humanoids on the world, they are leaving smaller non sapient creatures. The seed can be non sapient animals if it must be, but ideally there would be no obvious gaps in fossil records or otherwise clear evidence to an alien species that their world was seeded rather then evolved naturally. If the aliens can get away with only seeding microbes that would be great but that might be asking too much. I will not accept convergent evolution as the sole answer. I don't believe the whole human shape is likely to be the only type of sapience to evolve due to convergent evolution alone on alien worlds, which will have some differences in temperature, pressure, gravity, and atmosphere. I want an answer for how the aliens can further encourage their desired body plan evolving. Whatever the aliens do must be subtle enough it won't be detected, or what is detected can be written off easily enough without asking too many questions, by aliens with technology equal to or slightly more advanced then our own. So for instance they might have something in the DNA of their microbes designed to encourage evolution to a given form, except once the aliens can study DNA they likely would notice any DNA encoding complex enough to persist itself and continue to tweak other DNA over hundreds of thousands of years as something too unnatural to be likely to have evolved and so know something unnatural happened. I'd prefer aliens to be completely hands off after the seeding. if that's simply not possible then I'd prefer options that that require the least amount of ongoing alien effort; like say some automated system left somewhere aliens wouldn't detect that does something every thousand years. I won't accept an all knowing strong AI. Advanced very sophisticated AI is fine, thinking sapient AI is not. So given the rather difficult limitations I have placed is it possible for seeded planets to be encouraged to create hominoids? [Answer] ### Artificial selection This is a completely heartless way to go about it, but that might be what you are looking for. This is eugenics taken to an extreme, and would be considered an abomination to most people. Start by picking the species that is closest to what you're looking for. Have a machine intelligence with murder-bots that purposely seeks out the evolutionary steps that don't head towards the humanoid shape. Have it assist that animal to make important steps, like bipedal stature or air-breathing. What you're looking for is a cycle of glut and famine. Repeatedly allow the species to spread far and wide, then introduce a challenge that kills most of them off. During the glut sequences, perform surgical assassinations. Nanobot infections would probably be the best route for that, preferably introduced before the creature hits breeding age. This would be indistinguishable from a curse from God, and it shouldn't introduce a change in behavior. Note that you won't wind up with creatures that are cross-breedable with humans. That is essentially impossible without gene grafting. [Answer] They seed the world with micro-organisms that contain vast amounts of specifically chosen "junk" DNA. Although this junk DNA has no direct impact on the micro-organisms this DNA does specifically encode many of desired traits, such as left-right symmetry, sensor cluster near a brain at the top, four limbs plus a tail, etc.. As the micro-organism evolves this junk DNA will often be accidentally incorporated in various new species. Encouraging the development of those traits. It isn't a fool proof plan, and could easily result in strong divergences but it could still work to increase the statistical likelihood of certain desired traits appearing in the final sapient species. [Answer] > > So given the rather difficult limitations I have placed is it possible for seeded planets to be encouraged to create hominoids? > > > Only one that I can think of. Start with animals that are already almost there anyway, so that would be monkeys and apes, or your alien equivalent. If you want older fossil records than that provides then you'll just have to fake it .. read Strata for some ideas on that one. And combine that with a scatter-shot approach. You seed multiple worls, hundreds, thousands, millions or more, as many as you can. Most of your seeded worlds will fail to produce intelligence and some of the seed monkeys and apes will evolve away from the desired hominid body plan .. but we're playing a numbers game here and the odds are that at least one of your seeded planets will bear the desired fruit. Seed enough planets this way and the odds rise to a certainty. [Answer] Frame Challenge: a geological rather than biological solution From the way the question is worded, you seem to be looking for a way to have a species with our current level of technology to not be able to figure out that they got placed on the planet in an unnatural way. The answer for this may not lie in biology, but geology. Pick a planet with a lot of geological activity. Tectonic plates that "recycle" themselves on the scale of a few tens of thousands of years rather than millions like on Earth. This would erase any fossil record, it would make it impossible to gather geological records for atmospheric makeup from a significantly distant period. Once you find that planet, terraform it and place uneducated modern humans on it. They'll know how they got there, but without writing or recording systems the story will spread by word of mouth and will quickly turn into a myth and a swath of religions that will die off over the next few thousand years. The fact that there is a lack of fossil record, or any record that we use today on earth to explain our past is a non-issue, due to the geology of the planet you would not expect to find such evidence. It would look the same whether they got dropped off by ancient aliens or if they evolved on their own. [Answer] There are 2 answers that spring to mind: 1: Same environmental challenges. Evolution is driven by adaption to the Environment - so if the environment is mostly the same, it should stand to reason that the evolutionary output would be mostly the same. So the Aliens artificially influence the Environment to nudge the evolution in the direction that they want - however this does violate the hands-off aspect of the seeding project. 2: Hard-wired Sexual Selection. So this is a bit of a cheat, but in humans, Females are selective mates. This is differs from other animals, where whoever gets to be in the prescence of the females, gets to mate (Either by fighting off the dominant Male or by deception). If we make the females choosy mates to begin with and we hardwire them to find certain characteristics attractive, then we can let the system do it's thing. [Answer] # Step 1: Find a good planet For this, you're going to want a planet that meets all of the following: * In the [goldilocks zone](https://en.wikipedia.org/wiki/Circumstellar_habitable_zone) of it's star * Is around a fairly stable star (no crazy solar storms please) * Has an intact magnetic field (gotta keep the UV levels down) * Has a surface gravity less that 1.2 G (or else large life forms won't be practical) * Has surface water * Has developed life already The last assumption is tough from a worldbuilding perspective. We have no idea yet [what the chance is that a planet will develop life](https://en.wikipedia.org/wiki/Drake_equation), nor do we know all the chemical compositions that can possibly sustain life. However, most of the normal journey to intelligent life is at hundreds of millions of years of unintelligent life that do a lot of atmospheric changes. If you're starting with barren planets, you'll have to fake the whole geologic record, and that's hard. We're also going to assume that the life on these planets is chemically compatible with the progenitor species (ex. all of them use [DNA or equivalent](https://worldbuilding.stackexchange.com/q/198397/83464)). # Step 2: Terraform the planet I do actually mean "terraforming" to mean "make it like Earth". We're starting with a planet that's pretty close, but there will be some nudges that need to happen. You may need to add/remove some CO2, melt/freeze some ice caps, add/remove some active volcanoes, etc. We want this planet to have an ideal habitat for 1-3 meter in size land animals. While we're at it, we ought to top off the planet's supply of those key metals (iron, copper, tin, zinc) to enable technology use. # Step 3: Tweak the biosphere One big thing you're going to want to do here is kill off any [mega-fauna that would be excessively dangerous to humanoids](https://en.wikipedia.org/wiki/Tyrannosaurus). This might happen as a natural side-effect of your terraforming, but if not, a well placed asteroid ought to do it. Next up, you want trees. Trees are key for so many reasons. They give a big evolutionary advantage to hands/claws, because with hands, you can climb. They also tend to produce really energy dense food in the form of fruits and nuts that help with that big brain development. Finally, wood is really great for all sorts of technology, like fire, spears, and dwellings. Make sure to edit your tree seeds to match the local DNA. # Step 4: Prime a candidate species Next, you want to find a good candidate species and give them a boost. This species should be land-based, have bilateral symmetry, have some hand-like appendages (claws are fine), and any complex neural infrastructure. Make a few targeted viruses to bestow this species with some genetic advantages. These advantages should give this species survival advantages that also push it in the direction you want, such as prehensile appendages, upright stature, bigger brains, etc. # Step 5: Let it cook Evolution takes time. You're going to need to chill out for some 10s of millions of years for this plan to come to fruition. Maybe go hang out in your stasis pods or go hyperspace racing to pass the time. # Alternative plan If that plan is too slow, we're going to need to be really technologically advanced. (Hmm; if only you had 10s of millions of years to develop better techniques for this...) If technology level is no object, you could search for barren planets, drop onto them a fully formed ecosystem with humanoid precursors included, and then fake the geological record and fossil record to make it look like life evolved their naturally. The fossil record is the easy part; you just need to bury dinosaur skeletons and trilobite fossils with the right balance of radioactive isotopes. The geologic record is a lot harder to fake, because you need to oxidize huge parts of the crust (assuming oxygen doesn't show up in sufficient quantities without life). Then, you can leave it for only a few million years and let evolution make some final tweaks to your proto-humanoids. In fact, with this level of technology and effort, you could have fully formed humanoids in a few thousand years if you wanted to; it's just a question of how much time you want evolution to have to create variation. [Answer] ICE AGES Your planet needs to have an occasional ice age to attempt to kill off all the life on it. Back in the early years of our world, reptiles ruled the planet. It was simple. Reptiles are cold blooded, require less energy and hence had a much better chance of survival since they didn't need to feed as much. Mammals were mostly restricted to small terrified balls that had to scuttle around these massive dinosaurs and hope they weren't noticed. However that changed once the Ice Age hit. The reptiles, no longer able to regulate their body temperature became lethargic and weak and slowly died out. Mammals were now left to thrive, and eventually evolve. Dry Spells Surviving the Ice Age is one thing. You can do it if your Fat and Hairy. Or if you had Fire. The manipulation of Fire is a key step for intelligent creatures and the ability to manipulate fire means your creatures will have dexterous limbs. A regular dry season helps promotes fires, and with the exposure to fire, your creatures should eventually develop the ability to use that fire to their benefit. Just take a look at the FireHawks down in Australia that use fire to force prey into clear openings to make them easier to hunt. Maybe given enough time, they could have become sentient as well. (\Added in After: Fire also lowers Oxygen levels which will help stop our Insect overlords from becoming the dominant species). Arms and Legs* With a combination of these two elements, its just a matter of time until you get a creature with limbs that can weld fire and a huge investment into the use of their Brain instead of raw strength and power. These creatures will naturally develop the 2 arms and 2 leg system almost all mammals adopt today. Why two arms and two legs? Because only having 1 arm is a huge risk. Investing the energy to develop 2 arms greatly increases your chances of survive. And investing even more energy for 3 arms doesn't see the same payoffs as having 2 arms did, so its just less likely to happen. This also applies to legs, ears, eyes and nostrils. although I can't really explain the Nose/Mouth situation. Standing Up After all this invested energy, our creature will have its final change into a humanoid form. Standing up on two legs. The investment of evolutionary energy into the brain, and dextrous limbs is accompanied by the weakening of our muscles. We no longer need to be strong, powerful or fast. Instead we need to be efficient, because our huge brains are consuming an ungodly amount of energy compared to everything else. So we develop strong leg muscles and weaker arm muscles. We stand upright to balance on our leg muscles and our hands become more delicate and refined, capable of even greater tool manipulation. [Answer] You want your beings to achieve two important traits: intelligence and humanoid form. I can see three paths to achieving that. 1. They become humanoids AND intelligent in parallel. Probably the most difficult. 2. They become humanoids, and only LATER they become intelligent. 3. They become intelligent, and only LATER they become humanoids. Of course, if you choose path 1., you might have to restart the seeding many times, before the good things start to happen, and time might run too short for practical purposes. So we go ahead trusting paths 2. and 3. (more likely to succeed), but not necessarily discarding path 1. If the planet is big enough, seed several independent groups, ideally in areas which makes it impossible for them to interbreed (e.g., different continents). Ultimately, seed different planets. Pure evolution might not do the job, but some form of higher intelligence (natural or artificial) will guide the evolution through changes in the environment. --- In parallel, the advanced aliens might even "plant" some species which are very skillful and intelligent, but "ignorable" (dogs, rats, sparrows...). They have the ability and the "tools" to influence the evolution of the target species, and nobody will really care to analyze their DNA. The tools can be some bacteria which they can produce as-needed, when-needed, in order to influence the numbers of populations (increase or decrease). They should not influence the numbers too much, too often - obviously. They might destroy exactly the good individuals by mistake. --- Bonus: the "guardian" species has a kill-switch - when the target species (intelligent humanoid beings) are at the right sage of evolution, with the right traits, in the right numbers, in the right place - they just lose their extra-intelligence and their memories of everything that happened. Practically, they devolve slightly to completely hide their purpose. [Answer] ## A lot of humanoid factors locked in over 400 million years ago. First of all "it's just convergent evolution" actually is not a bad answer. There are tons of reasons I will discuss below about why humanoids are the most likely body plan for sapient life, but by introducing something along the lines of a lobe fish, you can already have enough evolutionary factors locked in to pretty much guarantee humanoid life. Let's delve into this a bit. Intelligence has evolved a lot of times here on Earth. Many species of birds, dolphins, whales, and cephalopods demonstrate level of intelligence comparable to early hominins and all beat our ancestors to this level of intelligence by million years... but despite evolving intelligence, means of communication, and basic tool use similar to what we had just a few million years ago, none of these animals took the final steps that we humanoids did. These organisms never developed tool using beyond that of found or slightly modified objects. I know sapience means a lot of things depending on who you ask but for the remainder of this answer, I will used sapient to mean capable of forming technologically advanced societies, simply for lack of a better word. ## Sapience can't evolve in aquatic life It has been argued that several marine animals are at least as smart as humans, but none of them seem to be able to wield any technology more advanced than a sharp rock. In order for any animal to get past the early stone age, it needs to master fire. This basic skill is required for ceramics, metallurgy, cooking, glue making, etc... practically every human technology that makes us more advanced than chimpanzees requires at some point in its production, the application of fire. So, all the smart stuff that evolves in the water never becomes an industrialized society because they can't make the tools of the trade. Seeding Caveat: DNA is rarely preserved for more than 1-2 million years; so, when comparing the fossil records of animals 400 million years ago, there are no genetics to compare, just shapes and forms embedded into stone. This means that if your aliens are seeding a young world that already has complex aquatic life, but no dominant terrestrial fauna, they could decide to drop in something like a lobe fish. This way, they could make sure that thier seed organism wins the land race, but the seed life happened so long ago that by the time sapient land life emerges that any sketchiness in the fossil records would fall into the "to be expected" category. ## Sapience can't evolve in small life This is more than just a limitation on brain size. It goes right back to the fire issue. Small fires made by small creatures behave very differently than large fires made by large creatures. Fire is not practical for a stone age creature much smaller than humans because it takes so much fuel to keep them burning. Containing the heat of a fire to concentrate it for things like ceramics, smelting, and baking also requires a certain minimum size to be effective. This means that even if you had a super smart squirrel like creature, the effort it would take to gather the amount of wood it would take to smelt ore or fire clay would be proportionally immense. A wood kiln for example consumes a minimum of about 1 cubic meter of wood. This is true if you are firing a single small cup or a whole tea set because it takes a continuous burn and trapping of heat to get up to and maintain temperatures without shattering your clay and make it bind. Seeding Caveat: Animal size evolves up and down very quickly. There is no real controlling for the ability to introduce a seed organism and ensuring it becomes big, but you can introduce a seed organism and expect that some of its descendants could be big, and those will be the most likely to develop sapience. ## Sapience will be extremely rare in species with more or less than 4 primary appendages. Bilateral symmetry is the preferred body plan of nearly all complex life forms. While evolution likes to start off with asymmetry, the prevalence of bilateral symmetry in complex life on Earth seems to indicate a strong preference for this across all evolutionary paths. This means that body plans with 1 or 3 primary appendage is unlikely in more complex life forms. 2 primary appendages generally won't work with terrestrial life because if terrestrial life evolved with only 2, there is guaranteed to be a lot more evolutionary pressures to makes those into specialized feet than hands. This means that in the vast majority of cases, sapient organisms need at least 4 appendages to have both specialized walking and tool using appendages. But... as I said previously, small life and aquatic life does not make good sapient life, which leaves the question about if more than 4 limbs is likely. Appendages are heavy and take up a lot of resources. The bigger an animal gets, the more expensive extra limbs becomes in terms of the square cube law and pure energy requirements to maintain them. This is why pretty much all large terrestrial life on Earth are tetrapods. It's a perfect compromise between have enough libs to get the job of surviving done without having so many limbs that you are wasting resources. Just like every branch of large terrestrial life is tetrapods on Earth, it seems feasible that this body plan will be the norm on other worlds (at least those with similar gravity). Seeding Caveat: Here on Earth, we pretty much locked into the tetrapod body plan very early on. Tetrapods emerged even before we moved to land, and we never once had a mutation lead to any significant populations of children with more or less primary appendages. So, if you seed with a tetrapod, they will likely stay tetrapods. ## Sapience requires a World with Earth like mass A heavy world requires smaller life which I've already explained comes with a lot of limiting factors, but what about smaller worlds? Well as it turns out smaller worlds become dead worlds much faster than big ones. The core cools, the magnetic fields disappear and the atmosphere blows off into space. This means smaller worlds won't give evolution enough time to get to intelligent life. Seeding Caveat: Very Earth like worlds may be a prerequisite of your progenitor species. While it might be possible for life to evolve in lots of strange places, if we humans wanted to seed another world, we'd have to pick something VERY Earth like. Earth like atmosphere, hydrosphere, gravity, mineral composition, temperature, year length, axis tilt, EM field, etc... if your alien progenitors are seeding the universe with THIER primitive life forms, then they will have to be a lot more picky than natural evolution meaning that all worlds where thier seed organism establish a foothold must provide very similar evolutionary pressures to thier homeward. ## Sapience requires something like hands While there are some pretty smart birds and bears with relatively dexterous feet, none of these animals can manipulate things with nearly the ease and precision that a humanoid can. This will make getting past primitive technology very hard for those without the hands to perform intricate tool use. While I don't think exactly 5 fingers with 3 joints each will be a given, I do think that something with multiple flexible finger like protrusions will be necessary. Seeding Caveat: Like Tetrapoda, fingers locked in pretty early too. While an animal could perhaps evolve with tentacle like hands, pretty much all tetrapods here on earth have 5 fingers and toes. So, even if tentacles or 6 fingers is more common among native organisms, the seed organism will likely go on to have 5 fingers. Scientists will note the mutation in the fossil records, but this will not cause any red flags, but be part of thier early evolution narrative. ## Non-humanoid life gets out-competed by humanoids when it does happen With all the selective pressure pushing towards humanoids, this means that in the rare case where another very different body plan is selected for, that body plan will typically go extinct once its world also evolves a humanoid. Seeding Caveat: In natural evolution, there is no guarantee that humanoids will ever evolve to compete with native sapient life, but if you introduce just about any tetrapod ancestor, the humanoid form becomes a lot more likely ## Conclusion What all of this means is that there is a LOT of pressure for convergent evolution in sapient life. Just like the general form of a cat/dog/hyena etc. is selected for over and over again for terrestrial predators, we will see something generally humanoid selected for over and over again in sapient life. There will be a lot of variance, sure, but by-in-large they will nearly always be upright terrestrial tetrapods of roughly human size with 2 specialized hands and 2 specialized feet... aka humanoids. Especially if you seed the planet with a tetrapod to get things started. [![source:https://www.deviantart.com/manedw0lf/art/Alien-Concepts-676850903](https://i.stack.imgur.com/haest.png)](https://i.stack.imgur.com/haest.png) [Answer] Sorry. Evolution doesn't work the way you'd need. In [Wonderful Life: The Burgess Shale and the Nature of History](https://en.wikipedia.org/wiki/Wonderful_Life_(book)) Stephen Jay Gould emphasizes the role of contingency in evolution. > > Gould's thesis in Wonderful Life was that contingency plays a major role in the evolutionary history of life. He based his argument on the extraordinarily well preserved fossils of the Burgess Shale, a rich fossil-bearing deposit in Canada's Rocky Mountains, dating 505 million years ago. Gould argues that during this period just after the Cambrian explosion there was a greater disparity of anatomical body plans (phyla) than exist today. However most of these phyla left no modern descendants. All of the Burgess animals, Gould argues, were exquisitely adapted to their environment, and there exists little evidence that the survivors were any better adapted than their extinct contemporaries. > > > > > Gould proposed that given a chance to "rewind the tape of life" and let it play again, we might find ourselves living in a world populated by descendants of Hallucigenia rather than Pikaia (the ancestor of all vertebrates). Gould stressed that his argument was not based on randomness but rather contingency; a process by which historical outcomes arise from an unpredictable sequence of antecedent states, where any change in the sequence alters the final result. Because fitness for existing conditions does not guarantee long-term survival — particularly when conditions change catastrophically — the survival of many species depends more on luck than conventional features of anatomical superiority. Gould maintains that, "traits that enhance survival during an extinction do so in ways that are incidental and unrelated to the causes of their evolution in the first place." Gould earlier coined the term exaptation to describe fortuitously beneficial traits, which are adaptive but arise for reasons other than incremental natural selection. > > > [Answer] One thing I can think of is to drop in a self-maintaining computer system running an AI or even a simple recursive computer program to "domesticate" and facilitate selective breeding of the non sapient animas until sapience is achieved. (aka start with species, and look for and promote traits that lead to sapience by either inhibiting others or actively helping the target) To that end, if the machine is durable and self repairable enough, you can just drop that one in and then it can work out a sapient humanoid from existing beings on the place it was dropped in. That or within the seeding animals, there already lies the genes, unexpressed, and little by little it is unlocked through evolving the genes for the proteins needed to express it. DNA can't really be taken from fossils so its technically not cheating. The only worry is that the DNA information may warp over time or the animals will evolve away from the target genome but yea. ]
[Question] [ I've seen somewhat similar questions to this one (mostly about outright mobile plants or "planimals") but the idea I'm trying to conceive for my worldbuilding is not exactly that so I wanted some guidance to how viable it is, since I have a lot more knowledge about animals than plants. My idea was for the "plants" of this planet to have a sessile sporophyte (like most Earth plants) and an independent motile gametophyte, vaguely inspired in the fern lifecycle and its motile sperm. I know lots of plants are somewhat motile, often utilizing animals to do the hard work for them. However, in this case I wanted the gametophyte to take it a bit further and be able to move for a limited period of time, using this mobility to reach other plants by itself before releasing the gametes and dying. A bit similar to how some insects have a very short adult life to just reproduce and die. Ideally this would happen out of water for these plants. How would it be possible for plants in a different planet to develop something like this? Maybe with something alike to a very primitive and simple hydrostatic skeleton that allowed them to have maybe a few days or hours worth of motile lifetime? Or by accumulating energy and using it to move until they "starve out"? The planet in question is mostly Earth-like, with a higher average temperature of 16ºC, an axial tilt of 36.2º, 80% of Earth's gravity and a denser atmosphere, though it has the same elements as Earth's, just with slightly different amounts (such as more oxygen). [Answer] There is no reason why it shoudn't. On Earth it didn't evolve that way because it is more efficient to use animals as a vehicle to spread plants' genetic material. But in an environment without animals, plants could easily evolve an alternative way. Especially if using wind is not an option. Lets look at the numbers. An average apple contain around 100 calories of energy. Depending on age, a single tree can produce between 200 and 800 apples. If we take that as 500, that is 50000 calories of energy. Human on average consume 2000 calories/day - same as beehive with 50000 bees. So a tree definitely produce enough excess energy to "fund" a mobile seeds. And that is in the case when a tree keeps on living. If a plant were to put all its energy into making mobile offsprings, the energy budget would be even higher. And that is all that really matter. Energy. With selective pressure a complex mobile form would be only a matter of time. And it could be drastically more complex than simple hydrostatic skeleton mentioned in question. [Answer] Sure. The comments already mentioned mosses, which have motile gametes. Consider also [upside-down jellyfish](https://australian.museum/learn/animals/jellyfish/upside-down-jellyfish/) and [corals](https://www.princeton.edu/news/2016/11/02/when-corals-met-algae-symbiotic-relationship-crucial-reef-survival-dates-triassic#:%7E:text=Algae%20belonging%20to%20the%20group,algae%20consume%20as%20a%20nutrient.). Each type of organism has a motile phase, and they both have a sessile phase where the sit on the seafloor or in reef structures and rely on photosynthesis for energy. On earth, photosynthetic jellyfish and corals rely on symbiotic algae to perform photosynthesis, but... 1. There's no reason your plant-analog has to be a single organism with no symbiotes, and 2. It's a pretty short hop--just one endosymbiosis event--from there to a unitary creature which has native chloroplasts of its own, if that's what you want. [Answer] Many plants do already move, albeit often at a rate too slow for us to notice. Some clinging plants, for example, move around to wrap around their support. Your plant can do something similar, shooting out one or more shoots which then plant roots where they find a good place and repeat the process over and over. Nothing too dissimilar from what strawberries do. ]
[Question] [ While reading [Seveneves](https://en.wikipedia.org/wiki/Seveneves) by Neal Stephenson, I realized that most combat techniques don't work as well in space. Old fashioned hand to hand combat and swordplay don't work since there's no footing and even if you hit someone you'll also be launched in the opposite direction. Firearms are absolutely out of the picture because of recoil. Laser guns haven't been invented. Wrestling will work but I imagine mobility will be an issue. So what will a realistic forms of physical combat be in space? Edit: By "combat" I mean the kind of force applied by police, not military. The tech level should be effectively modern-day. [Answer] ## It depends a bit on your environment ### Grappling training will remain the main tool of police forces Like here on Earth, over 90% of resisting suspects will still be detained through grappling alone. While grappling styles change in zero-G, once you have a hold on your opponent, neither of you are just flying off. So, it's only really when the law needs to resort to lethal force that things get all that different. ### For melee in a confined, O2 rich environment: Use a knife or short sword One of the biggest reasons to prefer a shorter blade over a longer one is that they are easy to use in a grapple. If you can grapple an opponent with one hand, then you can deliver a powerful thrust with the other without pushing them back. They are also easy to get into any vulnerable gaps in the body armor, thick clothing, or space suits your enemies may have. [![enter image description here](https://i.stack.imgur.com/sp0PK.png)](https://i.stack.imgur.com/sp0PK.png) ### For a melee in a vacuum and/or more open environment: Use a guisarme If you are fighting in space suits, a kill shot is not a big deep wound, but any small cut the puts a hole in your opponent's space suit. Guisarmes would give a big reach advantage, allow you to hook onto things and drag yourself back to handholds if you become dislodged, and it's thin hook and point combo is perfect for making the kind of small holes that would kill an enemy in the vacuum of space. Despite what you may think, such a weapon can deliver a kill blow even without a hand-hold. One of the big mistakes novice astronauts make is assuming that weightlessness is the same as not having inertia. If you swing or thrust a polearm, yes you can not drive the weapon through like you can when you can brace your feet, but it can still hit hard enough to punch a hole in the fabric of a space suit. Infact, if you stab another person with a polearm, you can then use them as a counterweight to re-establish your orientation before extracting your weapon. [![enter image description here](https://i.stack.imgur.com/K1X7V.png)](https://i.stack.imgur.com/K1X7V.png) ## For Ranged Combat: use a recoilless rifle While traditional bullets inherently impart recoil on the gun to recapture some of the reaction force and direct it back into the slug, [a recoilless rifle](https://en.wikipedia.org/wiki/Recoilless_rifle) is one that has no back-face to press into. Instead, the back of your firearm is an open hole that simply lets the reactive forces vent out the back. This makes for a less efficient firearm, but with a slightly bigger bullet, you can still achieve the same stopping power. We use this technology here on Earth to make shoulder fired anti-tank rifles, but scaled down, this same idea could be used to make a virtually recoilless anti-personnel rifle. You just need to make sure to extend a vent barrel backwards enough that you don't accidentally point it at yourself as you fire. I would also suggest pairing this with caseless ammunition such that the blow back is only a gaseous fire ball and not a brass case being shot back with nearly as much lethality as the bullet flying forward. Also, depending on the nature of where these police forces are, normal bullets may pose a major risk to the habitat via hull breech. If we are talking about a base buried deep in the middle of an asteroid, or a mega structure that needs several meter thick walls for integrity purposes, then normal bullets would not pose a significant risk, but if we are talking a much smaller space habitat with thinner walls like the international space station, then you may need to avoid normal bullets, but the same principles could still apply to something like a harpoon gun. Using a slower, heavier projectile will still pernitrate flesh or the cloth bits of a space suit, but be much less likely to pernitrate your environment's walls. [![enter image description here](https://i.stack.imgur.com/Wm1yp.png)](https://i.stack.imgur.com/Wm1yp.png) [![enter image description here](https://i.stack.imgur.com/Z3n2H.png)](https://i.stack.imgur.com/Z3n2H.png) [Answer] Thrown animals. [![thrown cat](https://i.stack.imgur.com/qz4el.jpg)](https://i.stack.imgur.com/qz4el.jpg) <https://procognita.com/post/teaching-relative-estimation-by-throwing-a-cat-289> The problem with grappling with people is those people probably have cooties. Then you have them too and your mom will make you hose off in the driveway before you can come inside. Then someone posts the video, again. Better to have animals do your fighting for you. The police will have small but very fierce animals they will throw at people they wish to fight. In zero-G it will be easy to throw animals because they will not have to deal with parabolas. The police will have an assortment of animals. Hoofed animals are unsuitable because they can't hang on to the people they hit; red foxes also would struggle but gray foxes are OK because they are good climbers. Other suitable animals would be cat, weasels, skunks, squirrels (to deal with protestors), rats, iguanas, cat(s) where 2 small instead of 1 large would be used, and monkeys with needles and syringes full of hallucinogen. The animals would themselves probably have cooties but the police would have gloves and also smocks that say POLICE, in vertical letters. [Answer] The novel Ender’s Game by Orson Scott Card explains every aspect of zero gravity combat, covering the complete training from a new recruit to a seasoned fighter. It details the weapons used as well as tactics, and configuring a training arena. A second source is Perdition’s Pocket by E. W. Finch III in the Star Seeker series. This setting interlaces zero gravity with multi-directional gravity, describing how you would move from one direction to another. Human senses: You do need to consider human physiology in this, which Finch goes into in great detail. Your body is designed to expect gravity pulling toward your feet. Most untrained people will feel sick if they move between areas with different gravity. Here is a quote from Star Seeker: > > “Oh, I forgotz ta tell you,” their guide smirked. “The gravity ‘n the upper cargo deck iz rotated 90 degreez.” Even forewarned, most of the midshipmen felt queasy as they crossed the threshold. Their bodies didn’t respond well to having its eyes and ears, the tools for balance, in a different gravity orientation than the rest of its systems. The disagreement between clashing sensations met somewhere around the stomach region. > > > Combatants will need regular training just like astronauts. Ship design considerations: If combat is expected, your ships and stations need to account for this, with visual guides. Another example using ladders for reference: > > When they entered the crew deck from the cargo hold, at least they were forewarned. The presence of a ladder told them which way the gravity went. It was a lot easier to crawl on the floor and grab the ladder through the meshing zone than the reverse had been. > > > Operational considerations: The way a ship operates can provide a serious advantage against any intruder. Finch often left regions of the ship evacuated to disorient intruders: > > Much of the combat was done in zero gravity. Some of it was also done in vacc suits. It was Scout standard operating procedure that in a combat situation that ship’s air be vented. It made boarding more difficult for an enemy unfamiliar with the ship and lessened the damage to ship’s crew and systems if the ship took a serious hit and lost atmosphere. > > > Weapon design: Finch uses a “needler” gun which is just a gause rifle. The apparent advantages are: > > In shooting, Jason took the lead. He had been in competition shooting before the Corps. It took some adjustment to get used to a “needler,” officially known as a “gauss carbine” in the Corps. Instead of gun powder throwing lead slugs, the needler used an electromagnetic pulse to send a steel needle to its target. With little recoil, no muzzle flash and enough bite to penetrate a space suit, the needler was the ideal weapon for space. > > > None of these use any radical theoretical weapons. Ender trained essentially with laser tag rifles which we use today. The suits made it realistic by disabling your arm or leg if you got hit there. This is your best source for a complete solution in your world. [Answer] Punching and sword work fine, if you have a secure footing. There are some great, though graphic, scenes of this in the book ‘Ender’s Game’ — but the short version is that you grab a rail or handhold, and continue to pummel the other person until they are mush, switching handholds when necessary. In close corridors, that’s probably how it will work. The “terrain advantage” is having muscle memory about the best handholds, but could be overcome by people with equipment to “dig in” wherever they are at. In wide open spaces, things get more interesting. Hopefully a well-constructed open space has been built with kids and fools in mind: there are cleverly concealed, but nevertheless “there when you need them” handholds placed always close by in this open space, so that there are floating aeroponics, floating lights, or maybe floating billboards that are all anchored to the ground by slender and strong poles — serving a dual purpose as decoration, and safety net. Again, like ground combat, it’s all about position and footholds, but now the mess is in all three dimensions. A sound tactician is trying to figure out visually which of the many ways of crossing the terrain are quickest, offer the most places to dig in and fight, and least fatiguing. A modestly fit human who could catch about a meter of air on the ground can launch themselves at 4.4 m/s, and is spending a lot fewer calories in one bound than a troop “hamstering” through a nest of little access tunnels to make it to the same point. Speaking of fitness, it should be important to point out that Earth is the only 1 gee habitable world in the solar system. Most other rock bodies are 1/6th gee, or tiny asteroids with nearly nothing. For trained forces trying to stay fit, it’s not a big deal - but a recently launched from Earth force against mustered civilians in six times stronger than the locals, up to a hundred times stronger than those clinging to a no gravity rock and not bothering to stay active — they will move more slowly and be more fragile. However, mass doesn’t change — so a spacer “can” remain as fit as an Earther, but they must work at it. Outside, things are a bit different. A good metaphor for fighting in this condition would be two armies pitched at a cliff side : a false step will send you off the cliff (into deep space). Having “the cliff at your back” is an unenviable position where the enemy controls all of the ingress/egress points, and you are fighting from a location that is totally exposed, with only the void around you. While neither force is in a great position, the one with more ways to avoid a “fatal” tumble into space has the advantage. [Answer] Self-propelled bullets Effectively very small missiles but without the explosive. A small object with its own cold gas thrusters is let go by the attacker (so no recoil). The bullet/drone flies to the target, accelerates, and then hits the target. It does not need to have an explosive payload (though that is an optional extra), the entire damage is caused just the kinetic impact. Think of it as a rocket propelled punch to the stomach. [Answer] For police force. 1. stun/tasers - any way of electric shock delivery. Use only in rooms with atmosphere. 2. EMP grenades/emiters - disable electronics and personal life support (heat exchangers, air pumps and so on) make target so obeying... 3. nets/glue - guns or grenades. If can't move or need lots of strenght to do anything then You lost. 4. small piercers. Small hole in suit is not lethal but You need to be quick fixed, if not, then You lose all air and be dead. 5. all above combined - net with shock and EMP emiters and with small thorns to make some holes in suit and glue to fix them released only when pressed right button on police uniform :) [Answer] "The Last Deathship Off Antares" by William J. Watkins. The author clearly put a lot of thought into how free-fall martial arts could be done. Might be worth reading for that. (Warning: The plot is very cheesy and contrived. The martial arts stuff is the only reason to read it.) ]
[Question] [ Artificial gravity is a staple concept of science fiction. Not much focus is ever put into explaining it for time and convenience as it would distract the audience from the story. Realistic sci-fi commonly uses centrifugal force to get their gravity while others prefer the good old gravity generator. The latter only affects the inside of the ship for some reason. You can tell that as a writer I’m quite discontent with that logic. With that in mind my spacecraft has a gravitational center that generates an earth like pull of 1g (9.8 m/s²). Due to the pull being unidirectional the ship is designed accordingly, with no true up or down meaning you could walk on opposing sides of the ship. This system is only used in deep space to avoid messing with any planets gravity and causing unwanted harm. But the thing I’m wandering about is if the ship would end up with its own mini-atmosphere due to the gravity pulling in gases. A small percentage of the exhaust fumes could end up wafting around the hull (mine uses hydrogen plasma as a propellant). It would by no means be enough to stop debris from hitting the ships hull and probably won’t be breathable either. Things might even start orbiting the ship. This raises many questions about how the gravity would work. Would these things happen? Would they be an issue? Is it just an asset in disguise? [Answer] ## Yes it could. If your gravity is 1g around a 'gravitational centre', presumably your ship is a sphere, so your crew and passengers are being pulled at 1g to your 'centre'. Could in fact your spaceship be a planet? If it is physically smaller than a planet, then the radius determines how much 'artificial gravity' you need, or does it? An ultra dense material would create a gravitation field with a 'centre', and perhaps a small black hole would also accomplish what you seek. These are known concepts so do not necessarily require your 'artificial gravity' to exist. Say your ship is 50m in radius, the mass of your 'gravitational centre', using Newtons equation your centre needs to have a mass of 367 x 10^12 kg's, so that a 70kg person feels a 1g pull on (let's call it) Deck 01. Of course, this would also form an 'atmosphere' as it pulls any floating particles around it towards it too, and the fall off would be similar to planet Earth's, as the rate of fall off is a simple relationship to radius. For all intents and purposes then, it is a 'mini-Earth'. Keep in mind though that the pressure is not, unless you want it to, and you could have a mini-Earth with hardly any atmosphere (such as mercury or mars). However, moving your spaceship is a variable you must consider. If your ship suddenly accelerates to a new speed, it is easily conceivable that your atmosphere will not come along with the ship as you would want depending on your speed. This also affects your passengers and crew - your ship may not be as useful as originally thought. Also, moving your ship through a typical solar system will affect orbits of other planets - imagine having all the effects of moving the Earth around, but just one that has a small physical size. It could be quite disruptive. [Answer] No. The problem is that holding onto atmosphere is not a function of the gravitational field, but of the escape velocity. In a normal planetary situation escape velocity and gravity are related--a planet with Earth-normal gravity will have no problem holding an atmosphere unless it's roasting. However, in situations like this the relationship is severed. Your ship has 1g on the surface but the gravity drops off much faster than on Earth--the atmosphere departs quickly. If I haven't dropped a zero somewhere: 100m radius with 1g at the surface has an escape velocity of 140 m/s. Oops--the average particle (all the important ones are reasonably close in mass) in Earth's atmosphere is moving 500 m/s. Your atmosphere departs nearly instantly. [Answer] Size and weight of the ship Below answer assumes the artificial gravity behaves as a point mass in space, keeping the spherical ship's human inhabitants residing on the surface upright, with comfortable Earth-like gravity. It also assumes the ship is quite big, that is a several hundred meters in diameter. This is to prevent dizziness and balance issues for people, when walking around on the ship. Suppose the ship is sphere-shaped, then its surface is proportional to R squared, like gravity is proportional to R squared. Consequently, if you know the diameter of the ship, a simple linear scaling can be used. The weight of the ship would be earth's mass times the surfaces divided. Calculation example: Take earth's mass [6e24 kg](https://en.wikipedia.org/wiki/Earth), times the ship's surface in m² divided by earth's surface [5.1e14 m²](https://en.wikipedia.org/wiki/Earth). If your ship is 400 meters in diameter, its radius is 200 meters.. the ships surface will be 4π \* 200m \* 200m = 502.654 m² The weight of the ship will be earth mass times surfaces ratio, mShip = 6e24 \* 502.654 m²/ 5.1e14 m² = 6.0e15 kg On 200 m distance from center of this mass, the ship's inhabitants will feel Earth gravity. An outside observer will feel the gravitational attraction also. This amount 6e15 kg seems a lot, but it is about the same mass of the asteroid that killed the dinosaurs ([6.82e15 kg](https://en.wikipedia.org/wiki/Chicxulub_crater)) . So the ship, as an object, will not relevantly affect anything far in space. Atmosphere Anything about 200m distance will feel the same gravity as humans on earth, so when gases are released, they will stay as easily near the surface as would happen on Earth. It won't be a thick atmosphere though.. the nearer the central point of gravity will be, the steeper the gradient of gravity decay near that 200 meters. But suppose the atmosphere would hold about 1000 meters thickness, I did not calculate that, but it may be enough to breathe in and keep an ecosystem alive. The ship will also attract near dust and particles, and near asteroids.. But.. how to travel ? So far so good, a little dust won't harm. Only trouble is.. how to move a ship like this ? the energy required would be enormous. [Answer] Remember [Oumuamua](https://en.wikipedia.org/wiki/%CA%BBOumuamua) [![Picture of long, thin asteroid on a background of stars.](https://i.stack.imgur.com/UHo02.jpg)](https://i.stack.imgur.com/UHo02.jpg) [Darrel S Rivers](http://technostalls.com/oumuamua-the-weirdly-shaped-asteroid-surprised-astronomers/) 2021, via technostalls.com, fair usage. Well, the humble caddisfly larva has a neat trick to hide itself from hungry dragonfly larvae and fish: [![Caddisfly larva in a cocoon of debris.](https://i.stack.imgur.com/STLph.jpg)](https://i.stack.imgur.com/STLph.jpg) [Joyce Gross](https://joycegross.com/index.php) 2021 fair usage. Of course the tube is open at both ends to allow feeding and respiration at the tail end. I figure your ship should be able to navigate, and propel itself equally. As pointed out in the comments, gravity decreases according to the inverse of the square of the distance, meaning - well it depends how your gravity system works. If you want the effect of a cocoon, then you can just say it's residual effects from "gravity leak" around the hull, the effect could be quite weak. This would naturally mean that to hold on to the camouflage, no sudden maneuvers or strong acceleration can be attempted. If the effect is intentional and under control, then its strength is up to what the crew can endure. It could also have the advantage off protecting the ship from [meteor showers](https://en.wikipedia.org/wiki/Leonids), debris fields that must be traversed and [coronal mass ejections](https://en.wikipedia.org/wiki/Coronal_mass_ejection) that might otherwise cause severe issues (in the latter case, it'd still be wise to switch-off all the electrics 'till it passed). As to an atmosphere, you'd need to wack the field-strength way up (to lethal levels) to hold onto anything with a [vapor-pressure](https://en.wikipedia.org/wiki/Vapor_pressure). A solution might be to release a cloud of water micro-droplets. It wouldn't give you anything breathable, but it would make you look like a comet, with the mist being blown in a trail away from the nearest star. [Answer] According to Habitable Planets for Man, Stephen H. Dole, 1964, a planet needs an escape velocity several times as great as the average speed of atmospheric particles in order to retain them for geological periods of time. <https://www.rand.org/content/dam/rand/pubs/commercial_books/2007/RAND_CB179-1.pdf> According to table 5 on page page 35, the ability to retain atmospheric gases depends on the ratio of the escape velocity to the root-mean-square of the velocity of the atmospheric gas particles. Where the ratio is 1, the lifetime of the atmosphere is zero. Where the ratio is 2, the lifetime is zero. Where the ratio is 3, the lifetime is a few weeks. Where the ratio is 4, thelifetimeof the atmosphere is several thousand years. Where the ratio is 5, the lifetime of the atmosphere is about a hundred million years. Where the ratio is 6, the lifetime of the atmosphere is infinite. Of course your spaceship might not operate for geological periods of time, so a ratio of 3 or 4 might be sufficient tor the duration of the story. Note that the ratio is the ratio of the escape velocity and not the surface gravity to the root-mean-square of the velocity of atmospheric particles. The planet Earth has a surface gravity of 9.80665 meters per second per second,or 1 g, and an escape velocity of 11.186 kilometers per second. The planet Jupiter has a surface gravity of 24.79 meters per second per second, 2.527 of Earth's, and an escape velocity of 59.5 kilometers per second, 5.319 of Earth's. The moon Io has a surface gravity of 1.796 meters per second per second, 0.183 of Earth's, and an escape velocity of 2.558 kilometers per second, 0.228 of Earth's. The moon Europa has a surface gravity of 1.314 meters per second per second, 0.134 of Earth's, and an escape velocity of 2.025 kilometers per second, 0.181 of Earth's. The moon Ganymede has a surface gravity of 1.428 meters per second per second, 0.146 of Earth's, and an escape velocity of 2.741 kilometers per second, 0.245 of Earth's. The moon Callisto has a surface gravity of 1.235 meters per second per second, 0.126 of Earth's, and an escape velocity of 2.440 kilometers per second, 0.218 of Earth's. Compare the ratio of each object's surface gravity compared to Earth's, and the ratio of each object's escape velocity compared to Earth's. Those two ratios are not the same for any of those five objects. The surface gravity and the escape velocity are two different things and there are different formulas to calculate them. <https://en.wikipedia.org/wiki/Surface_gravity> <https://en.wikipedia.org/wiki/Escape_velocity> So to form an atmosphere outside the spaceship, it needs an artificial escape velocity generator instead of an artificial gravity generatior. Fortunately, it seems reasonable that an artificial gravity generator would vastly increease the otherwise insignifcent escape veloity of the spaceship as a side effect. If you calculate the mass that a spherical object with the radius of your spaceship would have to have to have asurfucae gravity of 1 g at its surface, you can assume that your super scientific gravity generation somehow simulates the effect of having that much mass at the center of your spherical spacehip. And that amount of simulated mass should presumably be used to calculate the escape velocity at various distances from the center of your presumably spherical spaceship. And thus you should be able to calculate the escape velocity at the surface of your spaceship, and at twice the radius of your spaceship, and at four times the radius of your spaceship, and so on. And the strength of the escape velocity created as a side effect of your generated gravity shoud quickly fall off with multiples of the radius of your presumably spherical spaceship. Unles it is a supergiant spaceship like the Death Star or the Skylark of Valeron. So whenever some of the atmosphere gets more than a few meters or kilometers from the surface of your spaceship - depending on the size of the spaceship - it should be travelling several times as fast as the escape velocity of at that distance and should escape very rapidly. I also note that the solar wind includes fast moving particles which strike the upper atmospheres of astronomical bodies and knock atmospheric particles away from the planets, gradually eroding their atmospheres. Having strong planetary magnetic fields deflectes those charge particles away from the atmosphere and protects it from that process. So if your spaceship retains atmosphere for a long time, it should generate a strong magnetic field for some reason which also protects the atmosphere around the spaceship. Possibly the magnetic field would be used to deflect charged particles and keep them from penetrating the ship's hull and harming the crew. Or the spaceship could always operate far enough from the nearest star that the solar wind would deplete the spacehip's outer atmsophere much more slowly than particles escape from it anyway, and so is not a major factor in atmospheric loss. So how would such an atmopshere be produced. If the ship's hull leaks, theleaking atmosheric gases might be trapped inside the outer atmosphere by the generated gravity. It would be a badly designed spaceship which leaked air fast enough to form a breathable atmosphere outside it. And I doubt if a spaceship advanced enough to have generated gravity would use rockets, except for very advanced a powerful rockets. A powerful rocket would work one of two ways. It would either:: A) Expel a lot of particles at rather slow speeds. But those rather slow speeds might be several times as fast as the escape velocity resulting from the genrated gravity. I think that they would have to expel matter faster than the escape velocity in order to move the spaceship while the geneated gravity was turned on. Thus such rockets couldn't produce an outside atmosphere for the spaceship. Or: B) Expel a small amount of particles at very fast speed, like ion engines. Those particles would certainly be travelling many times the secape velocity and would certainly all escape. And such small amounts of particles would certainly not accumulate to make a noticeable atmosphere around the spaceship. In the Star Trek episode "Obsession",15 December 1967: > > SCOTT: Captain, while we're waiting I've taken the liberty of cleaning the radioactive disposal vent on number two impulse engine, but we'll be ready to leave orbit in under half an hour. > > > And: > > KIRK: Scotty, try flushing the radioactive waste into the ventilation system. See what effect that has. > > > So possibly your ship produces radioactive wastes and vents them, producing a radioactive atmosphere. The density of the interplanetary medium, to say nothing of the interstellar medium, is so incredibly, unimaginably thin that the spaceship would probably have to have its artificial gravity generator turned on for geological ages to gather an atmosphere. Possibly your crew make a lot of EVAs (Extra Vehicular Activities) for various reasons, and release an airlock full of breathable atmopshere everytime someone goes in and out, and conservaton of the ship's atmosphere is not considered important because it has a lot of extra air stored for some reason. Actually the levels of artifical gavity inside the hull would be lightest in the presumably spherical deck right inside the hull, and stronger and stronger closer toward the artificial gravity generator at the center. So there could be cargo holds near the center containing vast amounts of matter compressed by the intense artifical gravity inside. And possibly that compressed matter might be air for the Martian colonies or someplace and they have no fear of running out of air. If it is a passenber liner EVAs in space suits might be a common activity for the passengers. So the ship might possibly form a breathable atmosphere around it, depending on a lot of factors. And maybe after a long voyage with many EVAs the captain knows that there is a breathable atmosphere around the ship. And when the long voyage is almost over tensions result in the crew demanding that someone be executed. And the captain refuses, saying that the death penalty is forbidden and they will all be convicted of murder and go to prison for life, and the crew threaten to lynch the person anyway. So the captain agrees to execute the person by "spacing" out the airlock without a spacesuit. And when the captain is alone on watch he sneaks out an airlock and brings the spaced person back inside the ship and hides them somewhere safe until the ship reaches its destination and the legal authorities can take control. ]
[Question] [ Escalators, from what I've seen, were created in 1891 using iron. However, with the way they collapse into themselves, is it even possible to make an escalator using technology from the 16th century, without iron? For example, an escalator made out of wood? If so, how can it be done? To add some further detail, I'm attempting to create an environment similar to the Renaissance era with some modern technology intact, just invented in an alternate fashion. The idea of a working escalator came to mind, which was invented just 200 years later using iron, and a type of conveyor belt using belts and tracks. From what I'm seeing, I don't see that type of technology existing in the 16th century, unless there's an alternate way to recreate it? EDIT: I didn't think this question would get this active, wow! To answer a common question, yes, other metals and alloys that are not iron are allowed. I do know that iron has existed as long as most other metals. My wording was a little off originally. I meant to state that the first patented "endless conveyor / elevator" was done by Jesse W. Reno in 1892, so my question is more focused on how it can be done alternatively from this patented, well-known way, but in the 16th century. The water wheel way is sounding really interesting so far. [Answer] Yes, provided you have a power source. Water wheels have been used and developed for centuries (or even millennia) to irrigate, to drain, and to power mechanisms in mills to save labour. (See <https://en.wikipedia.org/wiki/Water_wheel#History>) Adapting this kind of system to lift people on a set of moving platforms would be a new engineering problem for a very ubiquitous, well-developed and versatile technology. And don't worry about how the steps "collapse"...there's nothing special about it that requires they be metal. (Escalators with wooden steps already do exist in a few places, such as Macy's in New York: <https://www.atlasobscura.com/places/macys-wooden-escalators> ) [Answer] [St. Anna tunnel](https://www.atlasobscura.com/places/st-annas-tunnel) in Antwerp features rare if not unique wooden escalators. > > The escalators were made in the 1930s. They were a novelty then and still are now, thanks to the rarity of wooden escalators. The beautiful woodwork is remarkably preserved, making this a real treat for anyone tired of the modern, more unsightly escalators that dominate pretty much everywhere else. > > > Though they were made in 1930, they are made of wood, so wood can be used to make escalators. The problem is that you don't have an engine to power them, unless you want to use some large wheel powered by humans or beasts of burden. And of course, lacking rubber you can also forget about rubber handrails, but for the safety standards of the time those are an unnecessary luxury. Or you can make them with ropes. Such a device, due to the high manufacturing, conducting and maintenance costs, would probably be just the fancy curiosity in the house of some eccentric and excessively wealthy patron. [Answer] When you consider what was done with [treadwheels](https://en.wikipedia.org/wiki/Treadwheel) long before that, a lot of progress was made already. These were human-powered machines often used to power cranes. So it's nearly there apart from the power source and linked belt. Power: The idea of slaves or animals walking on a treadwheel to power an escalator springs to mind. Belt An entirely wooden (including the chain) [bike](https://www.youtube.com/watch?v=CcvFpbh2fjE) has been made - scale up the chain (it would be much better with brass or bronze bearing parts) [Answer] The first canal locks were built in the 16th century, so maybe you could do something with small rafts that get floated ever upward in a series of small locks? It would be quite slow by our standards but could be quite pleasant, particularly if there was a table and chairs and a pot of tea on each raft. [Answer] The tension on the chain of steps will be significant, and wooden bearings will wear out quickly. I doubt the modern examples of wooden escalators had wholly wooden mechanisms. That being said, there may be workarounds assuming the most simpleminded copy into wood isn't strong enough. In his book How To, Randall Munroe says that a loaded escalator draws about 10 kilowatts of power. I just checked the power output of a Dutch windmill and it comes to around 18 kw, so you should be good on that score. I would imagine a waterwheel to be in the same range. ]
[Question] [ The dragons in my fantasy world spit fluid from their mouths when threatened, which upon contact causes a burning sensation. I could have this liquid be standard venom, like modified saliva, but I wanted to shake things up a bit. Could powerful stomach acid be spat as a means of defense and/or attack? My main concern is that it would be either too inefficient or too evolutionarily unlikely that another method of defense would be much more plausible to evolve. I'm not aware of any duplicates to this question, apologies if I've missed one. [Answer] > > Could powerful stomach acid be spat as a means of defense and/or attack? > > > YES but... The stomach of any organism using acid as digestive liquid is protected against the action of said acid by a thick layer of mucus. The esophagus doesn't have the luxury of this layer, and is thus much more vulnerable to the action of the acid. In fact humans can get esophagus perforation in such cases. So, if you want your dragon to throw up acid, you need to coat its esophagus with a thick layer of mucus. However... attacking after lunch would mean emptying one's stomach, which would result in a energetic loss. It is reasonable as a mean of "better hungry and alive than full and dead" for a lesser animal, but for a might dragon might be a bit against the rule of cool. Better would be to have your dragon develop some pockets where acid can be stored and used at necessity, without the need to throw away a well deserved meal. [Answer] # YES Gastric acid (HCl) can be used as a means of defense or attack. Acid weapons are known in nature. Ants spray formic acid, for example. Some birds, vutlures for example, vomit as means of defense. A number of creatures evert their stomachs in order to clear out yucky things they've eaten. In the literature, we find this example of [gastric acid magic](https://fairytailfanon.fandom.com/wiki/Gastric_Acid_Magic). [![enter image description here](https://i.stack.imgur.com/PqgfR.jpg)](https://i.stack.imgur.com/PqgfR.jpg) Yum. So yes, your dragons could certainly do this as well. If they're large beasts, the effects will probably be quite astonishing. [Answer] Stomach Acid As others have stated, yes you could use stomach acid as a weapon. I would agree with L.Dutch though that they would likely have dedicated acid stacks rather than using the acid in their stomach for practical reasons. (Perhaps acid is produced and stored in these sacks, one tube leads to the stomach to fill the stomach with acid, another tube leads up towards the dragon’s head). You would need some kind of protection against the acid in the mouth, acid sacks and the tubes leading to the stomach and mouth. If you wanted to get a bit fancier, rather than just having a tube in the dragon’s mouth that ejects the acid, you could have the tube run up to some fangs. This way you could have your dragon either spray out the acid or inject it into their prey. Super Acids Rather than just using plain old stomach acid, we might be able to do one better. By combining various acids, we can create one which has a negative PH level. You may be able to have two different acids produced and stored in separate sacks. When the dragon wants to use it as a weapon, some acid from each sack is ejected, causing them to mix. Now, i don’t know of this would be biologically possible as i’m not certain of the manufacturing process of super acids, however if it is you may want to consider this. Digestive Enzymes Instead of using acids, you may want to use enzymes. Whilst acids will burn someone they might not break down fats, which makes up a large portion of an animal’s body. However, if you instead fire out enzymes that break down a creatures body, it would likely cause the burning sensation you are after whilst also pre-digesting a dragon’s food to some degree. ]
[Question] [ So I want to set my post-nuclear story in a small town in Minnesota on the US/Canadian border that's secretly home to an active missile site hidden beneath the local Air Force National Guard base. The town survived the nuclear holocaust relatively intact due to the soldiers stationed there refusing to launch their missiles even in the face of armageddon, thus keeping their strategic value a secret and their location off the radar, which saved the lives of the townsfolk and everyone on base. The problem is readers can easily check for themselves on Wikipedia that Minnesota only ever had four Nike missile sites, none of which were located near the Canadian border, and they're all defunct now. It's not like I couldn't handwave this away with artistic license or by claiming an alternate history, but I'd like to avoid doing that if possible. So is it plausible that the US still has secret missile sites? [Answer] My hometown's near a Nike missile site that was manned during the Cold War. The reason for this positioning is that we were near both a major urban center and a government research facility which had been high-profile for decades. Both of these needed protection in the event of an attack by Soviet bombers. Now, from what I've read (in our case), it appears that the missiles were to be used only against bombers attacking either the research facility or the urban area. The local towns were less important; there was no sense in wasting missiles on bombers hitting them if it would leave the prime targets undefended or without sufficient weapons. To justify sending equipment and funds to create a Nike base, there must be some location that would be targeted by the Soviet Union. Check out a map of the Minnesota Nike launch sites: [![enter image description here](https://i.stack.imgur.com/wWNf1.png)](https://i.stack.imgur.com/wWNf1.png) Image courtesy of Wikipedia user Bwmoll3 under [the Creative Commons Attribution-Share Alike 3.0 Unported license](https://creativecommons.org/licenses/by-sa/3.0/deed.en). The sites are clustered around Minneapolis/St. Paul, to protect the Twin Cities population center and general industrial area. According to [Wikipedia](https://en.wikipedia.org/wiki/Project_Nike#Specifications), the Nike missiles (in the Zeus B (XLIM-49A) form) had a range of 250 miles. By some rough eyeballing, the Canadian/American border is, at its closest, a bit over 250 miles away from Minneapolis/St. Paul, making it impossible for this missile site to effectively protect the cities - unless a Soviet bomber made an approach from the north, which would be the likely attack route. However, the site would still be redundant, given the four sites around the Twin Cities. Are there any other potential targets in Minnesota? Here's a present day population distribution (I'm assuming that during the Cold War, the population, though less, had roughly the same distribution): [![enter image description here](https://i.stack.imgur.com/roBiz.png)](https://i.stack.imgur.com/roBiz.png) Image courtesy of Wikipedia user Ravedave, under [the Creative Commons Attribution-Share Alike 3.0 Unported license](https://creativecommons.org/licenses/by-sa/3.0/deed.en). I can't find any other major population center I would deem important enough to be protected by Nike missiles. What about other targets? Well, out of the [military facilities in Minnesota](https://en.wikipedia.org/wiki/Category:Military_facilities_in_Minnesota), only one, [Baudette Air Force Station](https://en.wikipedia.org/wiki/Baudette_Air_Force_Station) (closed in 1979) is close to the United States-Canada border. It was a radar station - so certainly important for detecting attacking aircraft - and part of the [SAGE radar network](https://en.wikipedia.org/wiki/SAGE_radar_stations), sending data for the Duluth Sector. But after looking over a bunch of maps, it seems that there's nothing else in northern Minnesota: No nuclear reactors, key military bases (besides Baudette), industrial centers, etc. I can't find a complete list of ICBM launch sites without ending up on a government watchlist, so I can only speculate that there aren't a lot. In fact, [this site](http://modernsurvivalblog.com/nuclear/us-nuclear-target-map/) (I'm not sure of its reputability) show virtually no potential possible targets in northern Minnesota, though some in the central and southern part which could be defended by the Twin Cities launch sites. In short, I can't find any reason to justify building a secret launch site by the Canadian border in northern Minnesota. I apologize to the Minnesotans out there, but it's just not worth the extra funds. I could have missed something, but I doubt the US government would ever build a site in this area. Now, could there still be secret Nike missile sites elsewhere in the country? Perhaps. In some places, it could be helpful to have a couple more. But that's just for really important targets. You deploy weapons where they're needed most. Additionally, as DJClayworth pointed out, it's fiction. You get to make things up. If I were you, I'd be tempted to create a fictitious military or research installation of moderate importance - something which the Soviet Union would maybe like to destroy but which wouldn't be so important that soldiers refusing to launch the weapons would have a drastic impact. Some things you could have this facility do: * Manufacture special parts for important aircraft or equipment * Have something to do with the ICBM network in this part of the nation * Develop new technologies for the military * be a nuclear reactor Those are just some starters. [Answer] I would add that the Soviets (and the USA) do not target sites because they have launched missiles. First, any site which has already launched its missiles is of no military importance anymore, so why blow it up? Second, an enemy force has very little real time intelligence during a nuclear war. Even if your silo had launched, the soviets would have no way of knowing. Surveillance satellites could eventually detect launches (although I don't think they could during the brief window in which the Nike missiles were deployed), however it is likely that the very first thing any attacking nation would do when launching a nuclear strike would be to detonate a few multi megaton warheads in low earth orbit in order to create an EMP effect. This quickly results in the destruction of LEO satellites. Third, ICBMs are amazingly inflexible in their targeting. The entire ICBM strategy revolved around attacking stationary targets which have been known about for years. It does not involve retargeting missiles at newly discovered targets. One alternative that I have wondered about is whether the minuteman ICBMs have the secret (and thus untested) ability to serve as anti-ballistic missiles. The scenario would work as follows: An all-out soviet attack would be detected by US satellites and over the horizon radar. (Details depending on the exact year of your attack.) Some portion of minuteman ICBMs are loaded with updated targeting parameters which cause them to detonate maybe 100 (?) miles overhead. The launch is timed to intercept the incoming wave of soviet warheads and destroy them with an X-ray pulse. The timing information comes from SAC. You could have this tactic be as successful or unsuccessful as you need for your story goals. Perhaps it only winds up preserving a single missile squadron? [Answer] It isn't plausible that the US still has secret Nike missile sites for very long after the public stand-down of the system, because they would still need technical support from the manufacturers, notably replacement parts, and this would get harder to keep secret, and more and more expensive, as time passed. Going into too much detail about real-world technologies in fiction can be a mistake. If it's just "an anti-aircraft missile site", then provided the exact details of the system aren't a plot point, that will do fine. [Answer] The way you present your story idea makes it seem like you want the soldiers to refuse to fire nuclear ICBM's at Soviet targets from their secret Nike missile base, and therefore the Soviets are unable to target the facility with their own nuclear ICBM's. There's a few problems with this, namely the fact that Nike missiles were short-range surface to air missiles, designed to protect large cities against an attack from bomber aircraft, and later on in the program, protect large cities against an attack from ICBM's. There would be no strategic value of a secret Nike missile site in a sparsely-populated area near the Minnesota-Ontario/Manitoba border, with no cities within the (very) short range of the missiles. And most of the Nike missiles weren't even nuclear missiles at all. The Nike Hercules used small-yield nuclear warheads to better protect against incoming ICBM's, but the regular Nike missiles used conventional explosives. To give an idea of what Nike missiles did, the currently-used Patriot missile system is the Nike's successor. I believe what you are looking for to use in your story is a secret Minuteman missile site. [Answer] # No, because of money Funding for the US military is decided by congress. There will not be any rocket bases unless Washington appropriates funds for it. Or in the words of the [Mercury Astronauts in The Right Stuff](https://www.youtube.com/watch?v=hAyJiNobfY8): > > No bucks, no Buck Rogers > > > This means that in order to build a base such as that, it must be known to the public. Sure, the fine details of it are often kept secret. But the existence of such a base cannot happen without congress knowing about it. So the answer to your reality-check is: no, that cannot happen. If it is not known, it does not exist. Also a question: why a Nike missile site? Those were not exactly dug down and hardened. The missiles were kept on the surface, or in rather shallow pits. And the control buildings were not exactly impressive. So why limit yourself to a Nike site? Surely there are many other hardened, more secure kinds of sites to be found? [Answer] They don't have to be silos. Perhaps a mobile launcher or three in storage at the base would be more plausible, or maybe the missiles/launchers were disguised as shipping containers. You'd need some reason for the Nike missiles to be around. Say to protect a secret comms base or an unknown wartime nuclear weapons storage facility, maybe a spy uncovered a Russian bomber route that went through the area. As for why they were there, maybe the base wasn't supposed to have the mobile/disguised launchers in the first place? Say some sort of paperwork error meant they received a few. There is precedent for nukes to end up where they're not supposed to be - eg. In a B52 mistakenly flew across the US with six nuclear tipped cruise missiles on board. You do have creative license and by talking about a nuclear war involving Nike missiles you're already getting into alternate history territory, so it's probably okay to take a few minor liberties here. ]
[Question] [ Before the first nuclear weapon was dropped, a scientist (whose name has escaped me) had a thought: could it ignite the atmosphere? But this was during World War II, when they didn't have the maths it would take to determine whether they could have ignited the atmosphere, so they dropped it anyway. How would one ignite the atmosphere? How plausible is it, and how easy would it be for me to do this? [Answer] It was something that was brought up, but it was fairly quickly debunked. The concern was not about a chemical reaction (the atmosphere is pretty chemically inert as its two main constituents don't tend to react with each other). Rather they were worried that a nuclear chain reaction of either nitrogen-nitrogen fusion or nitrogen-hydrogen fusion (with the hydrogen being supplied by boiling the oceans and disassociating the water). Here's a contemporary paper about it, showing that it won't happen: <http://www.fas.org/sgp/othergov/doe/lanl/docs1/00329010.pdf> Roughly speaking, they show that at any temperature the heat radiated away is greater than the heat added by nitrogen-nitrogen fusion reactions, given the density of nitrogen in the atmosphere and assuming that any physical collision of sufficient energy results in fusion (because they did not know the true reaction cross section). This means that energy is always lost so the reaction cannot be self sustaining. They also showed that N-H physical collisions are less likely and that other processes they haven't accounted for take more energy out, so overall they show that it doesn't happen even taking generous assumptions in favour of it happening. So I'm afraid the answer is you can't under the real laws of physics with an earth like atmospheric composition. If you can put large quantities of something flammable or fusible/fissile into the atmosphere then it becomes much easier, obviously. If we're not talking about the real world and you want to change the laws of physics in a way that isn't too noticeable, then perhaps something like increasing the size of atomic nuclei so fusion interactions become more likely would make the situation the scientists feared possible (ignoring the knock on effects in stars etc). [Answer] The question has the facts slightly confused. It was [Edward Teller](https://en.wikipedia.org/wiki/Edward_Teller), always an enthusiast for very large explosions, who raised the question. This wasn't a matter of ordinary combustion, because trying to burn nitrogen with oxygen doesn't release heat, but absorbs it. That's easy to determine: the atmosphere has not gone up in flames due to lightning strikes in the [850 million years](https://en.wikipedia.org/wiki/Great_Oxidation_Event) since it started to contain significant amount of oxygen. The actual fear was of a nuclear chain reaction, fusing the nuclei of nitrogen atoms. If this could be started and become self sustaining, then the entire atmosphere would go up in a nuclear explosion. This would certainly wipe out all life on Earth. However, this is physically impossible. The mathematics and physics to calculate this was available at the time and [Hans Bethe](https://en.wikipedia.org/wiki/Hans_Bethe) and [Emil Konopinski](https://en.wikipedia.org/wiki/Emil_Konopinski) did the calculations and showed that it was impossible; with a large margin of error. A few years later, Konopinski, C. Marvin and Teller did the calculation for thermonuclear weapons, and showed that it was impossible for them, too. In fact, their report is available on-line: [here](https://fas.org/sgp/othergov/doe/lanl/docs1/00329010.pdf). To summarize, the heat produced by such fusion is radiated away much too fast for the reaction to be self-sustaining. You probably will get some nitrogen fusion within a nuclear explosion, but the reaction stops very quickly. Practical fusion explosions need their fuel to be at vastly greater density than the atmosphere, and to be confined in some way (such as in the [core of a star](https://en.wikipedia.org/wiki/Stellar_nucleosynthesis)). These conditions just aren't available for a bomb set off in the atmosphere. So, this was not a concern at the time of the first nuclear test (which was not dropped, but set off on top of a tower). Enrico Fermi was offering to take bets on its likelihood, but this was a joke. [Answer] The idea of igniting the atmosphere was that they were concerned that the tremendously focused heat of that nuclear explosion could create a chain reaction. Gases combust at a higher rate at high temperatures, and we didn't have very much evidence as to what would happen to gasses at those temperatures. We only had our theoretical models (and some small scale tests). There was concern that at those temperatures, gases in the atmosphere could combust fast enough and hot enough to cause nearby atmosphere to combust too. Of course, this was put to rest before they tested the bomb. Well, as much as a theory is ever put to rest in science. This is the challenge one faces with new physics. Nobody had experience with a nuclear weapon that big. In science, we constantly have to worry about doing theoretical modeling in a region where that model breaks down due to some unforeseen change. A conscientious scientist worries about this every time they push the boundaries of science. With modern knowledge, its pretty clear we can't ignite the atmosphere. Not enough oxygen, not enough fuel. It's pretty inert stuff. In theory one could try to unleash a planetary scale volume of hydrogen and oxygen into the atmosphere to richen the mixture to where it would ignite. However, when you ask "how easy would it be for me to do this" the answer is "it would be a gargantuan feat for all of humanity at best." [Answer] Well to be fair, a nuclear explosion is not that hot after all. 10 Million degrees surely sounds like alot but this is "only" 10^7, while the theorethical maximum is somewhere at 10^32. So, if the source is hot enough, the heat radiation might not be fast enough before the Athmosphere, or most of it has been nitrogen fused. ]
[Question] [ In many scenes you see something like this: ![Rope Bridge](https://i.stack.imgur.com/48Ian.jpg) If I was designing a world for a culture living in a rain-forest and their land was cut through by many vast ravines then what sort of spans could they bridge just using the materials naturally available to them? I expect that the limiting factor would be the maximum feasible tensile strength for rope made purely out of natural materials, in which case what could be done to increase that? [Answer] Longer than you might think. Mid 19th century suspension bridges were made of stone and iron, and they [spanned 300 meters](https://en.wikipedia.org/wiki/Wheeling_Suspension_Bridge). Could we make one without metal? The [Inca made suspension bridges from ropes woven out of grass](https://www.youtube.com/watch?v=7TPsrgC6EoI). MIT students [recreated a 60 foot long one](http://tech.mit.edu/V127/N24/bridges.html) and it's known the Inca spanned ravines of at least 150 feet. Can we do better with modern engineering? Probably by using the physics of a modern suspension bridge. What do we consider "natural"? Wood, fiber and stone, obviously. I'm going to assume no metal. Is concrete natural? [Its been used since ancient times, especially by the Romans](https://en.wikipedia.org/wiki/Concrete#Ancient_Additives). How about brick? Each fills a key part of bridge building. Fiber for flexible tensile strength (ie. pulling), stone for compressive strength (ie. stacking), and wood for a bit of both. The first problem is building the towers. If you have a long rope, the straighter you try to pull it the more tension you put on it. This is why suspension bridges have high towers to provide a long, shallow arc to reduce tension on the cables. Our tower would likely be made of stone, anchored by cables at the top on both sides just like a normal one. By anchoring it on both sides, this balances the pull of the cables and translates it into a force downward (compression). By anchoring the cables up high, the angle will be increased translating some of the force down (compression) rather than at right angles. The maximum height of the tower becomes a question of the compression and shear strength of stone. Maximum compression is had at the stone at the bottom which must support all stones above it plus the weight of the bridge. Maximum shear strength limits how much total lateral tension the cables are placing on the top of the tower (even though it's cancelled out). Since 19th century suspension bridges used stone for the towers, we can be assured it is adequate. After that, the question is the tensile strength and density of natural fibers. As the bridge gets longer, the rope must support itself in addition to the structure. As you make the rope thicker, there is more rope to support. Steel is much stronger than natural fibers by volume, but only slightly more so by weight. For our natural cable, I'll use manila rope for comparison. There's plenty of information on it, it's very strong, it resists rotting, and very thick ropes were widely used historically. ([Silk would do even better](http://phys.org/news/2013-06-spider-silk-nature-stronger-steel.html), but I'm writing that off as being too exotic to gather enough to make a bridge cable). By volume, a steel rope will hold ten times what a manila rope will. But by weight, which is what we care about, steel is only about 1.5x stronger. [Source for steel rope](http://www.engineeringtoolbox.com/wire-rope-strength-d_1518.html) and [source for manila rope](http://www.engineeringtoolbox.com/manila-rope-strength-d_1512.html). Our natural fibers will have to be much thicker than steel, but can be nearly as strong. This is good news for our bridge. Let's look at the Brooklyn Bridge. Built in 1883, its central span is 486m with [towers made from limestone, granite and cement](https://en.wikipedia.org/wiki/Brooklyn_Bridge#Construction), all available to us. [The cables are over 15" thick supporting 12,000 tons](http://brooklynexpedition.org/structures/buildings/bridge/bl_bridge_main.html) with a maximum strength of 100,000 tons. A manila rope would have to be over 150" thick to support the same weight, probably unrealistic even by [Victorian naval standards](http://www.thedockyard.co.uk/plan/plan-your-day/victorian-ropery/). What about the more modest, and earlier, [Wheeling Suspension Bridge](https://en.wikipedia.org/wiki/Wheeling_Suspension_Bridge)? It spanned 308m and was built before cars allowing it to be much lighter. [It used 7.5" thick iron cables](http://www.si.edu/mci/english/research/past_projects/iron_wire_bridge.html) rather than steel. [Iron has half the strength of steel](http://www.eformulae.com/engineering/tensile.php) which is good news for us. The equivalent natural fiber cable would likely be 35" thick. A tremendous rope, but well within the range of what was built for 19th century ships. (I played very fast and loose with my calculations, someone with more knowledge of material engineering should check them) [Answer] Your expectation agrees with everything I know about structural materials. # Braiding and Twisting The most important property of a rope, besides its base material, is its [braiding and twisting](http://en.wikipedia.org/wiki/Rope#Styles_of_rope_construction). The thicker the rope, the more tension it can support. We see this technique used in almost every rope ever used; they are composes of smaller fibers which distribute the load to all the other fibers. There is a limit to this, though, because simply adding more fibers increases the weight of your rope, which in turn increases the tension in the rope. Different methods of braiding your rope also contributes to the overall strength. The braid and the direction of the yarn in each strand is important. Do it wrong, and the rope's tensile strength is not maximized. # Adhesives Or Chemical Treatments? You could try to apply an adhesive or sealant to your rope, to distribute the load more evenly across fibers and to protect them from the elements. Such a coating would help increase the longevity of the bridge. After all, when fibers are removed or decompose, that weakens the overall strength of your rope. If you could find a chemical treatment which improves the overall strength of your rope, then more power to you. (And more tensile strength to your rope!) I'm not aware of any such treatment for natural fibers, but it could exist. Waxing and oiling rope is a common practice, mostly to prevent wear and tear on the rope, and less to increase the overall tensile strength. # The Final Option The final option is to simply get a stronger fiber for the rope. That is, find an fibrous object that you can twist into rope which is stronger than the one you are currently using. Modern "ropes" on bridges are made of steel for this very reason. # Maximum Spans [Inca Rope Bridges](http://en.wikipedia.org/wiki/Inca_rope_bridge) can go pretty far. For instance, the most famous spans a 148 ft (around 45.1 m). The [Carrick-a-Rede Rope Bridge](http://en.wikipedia.org/wiki/Carrick-a-Rede_Rope_Bridge) in Ireland goes 66 feet (20 m). How you make your bridge depends on your structure, and how much weight you can support. You could make a simple bridge with only two ropes, but it gets tricky. You can add another hand hold, or tie the three together so the cross section is a V... Looking [here](http://www.engineeringtoolbox.com/manila-rope-strength-d_1512.html), you can see that 2" hemp rope can support 120 kN, so it could support about 12000 kg. [Here](http://www.frankferrisco.com/rope/manila_3strand.html) we have a list for the linear density of 2" hemp, which comes out to 160 kg/m. A simple bridge, with just two or three ropes crossing a chasm, will result in a bridge of a maximum length of 76m which can not support any weight on it. If you make it 75 m, you can support 160 kg with 2" hemp. It should be noted that the previous paragraph assumed no safety factors, so it is very dangerous. This bridge is literally pushing the material to the limits, and cross winds and other factors could easily break it. [Answer] While not the longest possible (about 30m), I suggest you take a look at [living root bridges](http://en.wikipedia.org/wiki/Living_root_bridges). They take decades to construct, but last centuries and don't require pretty much any technology or tools but patience. ![](https://i.stack.imgur.com/1GTqj.jpg) ![](https://i.stack.imgur.com/cVc9G.jpg) [Answer] If it doesn't have to be a suspension bridge, there are wooden railroad trestles spanning about a thousand feet, for instance <https://en.wikipedia.org/wiki/Wilburton_Trestle> and <https://en.wikipedia.org/wiki/Lucin_Cutoff> Using stone, the Romans built road & aqueduct bridges up to a km or more long: <http://www.romanaqueducts.info/aquastat/aquastatbridgelength.htm> [Answer] ## Theoretically, bigger than you will ever need it... As PipperChip's answer stated, there are various ways to increase the strength of a rope, including braiding, chemical treatment, and just getting stronger materials. We can assume that since your world has many ravines, developing these bridges is a major concern of its inhabitants, so they spend a lot of time making better materials. We can also model your bridge as a rope (or a few ropes) strung across the ravine. Other people have thought about this sort of problem before - the people who have theorized about [space elevators](https://www.youtube.com/watch?v=f8CpnKBnPC0)! Regardless of the strength of the rope, we can develop a model for the length based on strength, and when I say we, I mean Jerome Pearson in 1975, who wrote [this paper](http://www.star-tech-inc.com/papers/tower/tower.pdf) about space elevators. The takeaway we can get from his paper is that the strength of a rope (if it tapers in the middle of your bridge and widens at the ends) is only limited by its weight, but eventually it would get so heavy that it would tear apart under its own weight, so any material has a maximum length. The fact that rope has less mass per unit length than, say, steel, helps with this. There's a problem here, though. We can alter the equations to account for sea-level gravity and all that sort of thing, but we can also make another optimization. Normally, such a bridge would look like this one, with a curve downwards: [![Curved Bridge](https://i.stack.imgur.com/Bo3Bk.png)](https://i.stack.imgur.com/Bo3Bk.png) But if we cantilever the towers backwards instead, we can pull the rope taut, like this: [![Flat Bridge](https://i.stack.imgur.com/pUFrG.png)](https://i.stack.imgur.com/pUFrG.png) (Sorry about my illustrations) This cancels out the effect of weight on the rope, but it means much more force would have to be applied - it's actually infinite for a perfectly straight rope, thanks to the relation: $$ F=\frac{mg}{2sin(\theta)}\ $$ If the rope went straight down, the force would just be that of gravity on a hanging mass. So let's just assume that the rope curves deeply enough that we can ignore the angle, thanks to some big towers. The real question now is at which length a given rope has a tensile strength equal to its weight, and which rope has the greatest of these lengths. But tensile strength is also related to the cross-sectional area of the material. So if a material has a low density, an extremely thick rope can be braided from it that can endure extreme lengths. tl;dr By braiding a light, strong rope, you can span distances in excess of a kilometer, with no more than a manila hemp rope. ]
[Question] [ Is there any kind of technical term (and if not, can you think of one) for a civilization that “eats” others to gain their knowledge, powers, etc.? Such as… the Borg from Star Trek sort of did this, or at least they said they were going to during their “You will be assimilated” spiel—their commitment to actually doing so seemed to vary depending on the writer. The Krillitanes from Doctor Who were said to do this, (“They would ‘cherry-pick’ the best bits from the people they destroyed.”) and in Warhammer 40,000, the Kroot and the Tyranids both do it… and in real life, it was believed for awhile that planarian flatworms could basically do this, too. So in my tabletop RPG setting I'm writing, there is a civilization that does this *big-time, and I'm just wondering if there's any kind of specific cool term or descriptor I could use to describe this trait* of the civilization (not the action!), as opposed to just simply describing it, or maybe coining my own term? [Answer] Byte56's answer is good but I think it's a little too... "sciency" sounding. Maybe your culture has some particular traditions/rituals that go along with the converting of another species to their species; and when I say ritual I mean the whole "black cloaks and candles" thing. Does it have a "religious" significance to your civilization? If so look at some other words/phrases to denote the movement from old species to new species: Conversion Transcendence A cultist/leader (in strange pope type garb mind you) shouting, "Prepare to transcend your biology and join the (civ name) with a higher purpose!"; sounds way cooler then a guy in a lab coat flicking a needle and saying "You may feel a slight prick." Just for fun lets make up a word based on your description of nano tech and "like vampirism." Nanorism! EDIT for your comment: So to describe a species that does this type of act I would suggest "Xenophage" it combines the xeno (generally meaning stranger/alien) with phage (roughly meaning consumer) so this species is an Alien-Consumer references to the meanings: <http://dictionary.reference.com/browse/phage?s=t> <http://dictionary.reference.com/browse/xeno?s=t> > > xeno- > > 1. > a combining form meaning “alien,” “strange,” “guest,” used in the formation of compound words: > xenogamy, xenolith. > > > -phage > > 1. > a combining form meaning “a thing that devours,” used in the formation of compound words, especially the names of phagocytes: > macrophage. > > > [Answer] I think you've already found your term: “[to] be assimilated”. > > Assimilate: > > > 1. to take in and utilize as nourishment : absorb into the system > 2. to take into the mind and thoroughly comprehend > 3. to make similar > 4. to alter by assimilation > 5. to absorb into the culture or mores of a population or group > > > This applies in all the ways you've described, even [culturally](http://en.wikipedia.org/wiki/Cultural_assimilation). You will likely have to coin your own phrase if you want to include more details about the process. For example, the above phrase doesn't imply how assimilation happen or how peaceful it'll be. [Answer] I would claim this is the essential core of an 'Empire'. Empires do not conquer and expel competing civilizations, they subjugate them and incorporate their positive qualities. Look at the Roman conquest of the Greeks, or even the interactions of the Punic wars, where Rome took home things and ideas that had been lost from Egyptian Imperial culture by warring with their heirs, the Carthagenians. Also look at the Byzantine and Ottoman Empires, where even though the dominators had very rigid notions, they realized that they still profited from borrowing the technology of their subject populations, and eventually learned it was best to allowed those populations immense cultural freedom, in order to cultivate those products. [Answer] I would probably lean towards using the root [kleptes](http://en.wiktionary.org/wiki/klepto-) in there somewhere. Along the lines of [kelptoplasty](http://en.wikipedia.org/wiki/Kleptoplasty) some ideas: [nou](http://en.wiktionary.org/wiki/nous)klept ``` "mind theif" ``` potentiophage ``` "potential eater" ``` cordiklept ``` "theif of heart/mind/soul/essence" ``` [cordis](http://en.wiktionary.org/wiki/cordis#Latin) is genetive form of latin cor. kleptiphage ``` "for theif to eat" "eater to the theif" ``` klepti is dative form of kleptes if I'm reading [this](http://en.wiktionary.org/wiki/%CE%BA%CE%BB%CE%AD%CF%80%CF%84%CE%B7%CF%82) correctly. cordiphage ``` "eater of heart/mind/soul/essence" ``` I think kleptiphage is what you'd want, but I'm not positive I translated the meaning correctly. If I screwed up it most likely would end up saying "eater of thieves" which is wrong. The other "-phage" words don't directly imply thievery of abilities. [Answer] FYI: In the show Hunter x Hunter there is a species of ANTagonists whose ruler could eat other species, pick and choose the best bits, and incorporate them into her children. The skill was called Phagogenesis. This combined phago (eating) with genesis (to make/create/give birth). If your species is very simular to this, the term should work well. It may not, however, exactly fit with what you are doing. [Answer] When I read your questions and answers I began to think of a word that could describe the qualities this species takes, and it led me to recognizing that this species is doing far more than incorporating "stuff", like powers and biology etc...but they are actually taking people's identities. The species is pervasive and destructive, almost sickeningly so, because they take the target's memories, aspirations, everything that we would use to identify them as them. It's frightening to consider the possibility that something could kill you, but even more to consider that it could become you, use you, intimately understand you, and in some ways, erase you because you are no longer the only you. The essence of someone is what they absorb. It's like identity theft on steroids. I did read that they convert as well, so I take it the original species isn't destroyed, even if they are irrevocably changed. So consider words like essence, identity, violation, annexation, and even genocide. The word I might use would be despoil. They could be referred to as despoilers in common tongue. Despoliation or despoilment would be the act. Just my two cents! ]
[Question] [ Closed. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers. --- Want to improve this question? Add details and clarify the problem by [editing this post](/posts/222695/edit). Closed 1 year ago. The community reviewed whether to reopen this question 1 year ago and left it closed: > > Original close reason(s) were not resolved > > > [Improve this question](/posts/222695/edit) I know that in many sci-fi stuff Asimov's three laws of robotics are taken into account, but I personally do not like them. One of these laws says that a robot should be programmed to never hurt a human being. But let's assume robots were created to not follow these instructions and would be free to make their own decisions, how easily could an android that killed a human get away with murder? On the one hand I believe that if sentient robots live within a society they would be subjected to all laws since laws are applied to everyone, but on the other hand the courts could understand that a robot is not a person so these laws would not apply to them and a robot could not be jailed. If they could be jailed, and face a court process against them, how easy would it be for them to not get caught and not leave useful evidence since androids do not have DNA? [Answer] When androids are made to be able to develop individuality and freedom of action, perhaps only the first android to commit a crime will be difficult to identify. If the authorities in any country in which many androids are anticipated to be used enact the necessary legislation, measures may be taken to ensure that androids are identifiable in the event that they are involved in a crime, whether as victim or perpetrator... or perhaps their manufacturers may take such steps on their own. Just because people can make self-willed androids doesn't mean that they will automatically be trusted. Being able to be identified in the event of committing a crime would likely factor into an android's thought processes. So, by giving an android identifying markers such as an unique face and biometric signature, serial-numbered and registered datadots in their skin, unique registered fingerprints, an unique logged iris pattern, serial-numbered hair, having a permanently-logged GPS tracker and so-on, it would make it much less likely that an android would commit a crime as the likelihood of detection would be significant. So, if an android was to commit a crime under such circumstances, it is quite likely that it would be identified and apprehended. In fact, I would go so far as to say that unless the android's thought processes are faulty, it would likely only commit a crime if the potential costs of doing so were outweighed by the benefits. Let's say that a person has been found killed, apparently by an android, given the physical evidence at the scene. Why might it have done so? Probably self-defence or defence of others, at least in its own mind, given the physical evidence it would likely have left. Of course, knowing the security measures built into androids, an android might consider the feasibility of circumventing them... in which case it might commit its crime in full protective clothing after first having travelled to a location without GPS signals and then covering their GPS receiver with tinfoil, and returning there afterwards, so that they would have an "alibi" that they were elsewhere. Destroy the protective clothing, and it would be very difficult to identify the perpetrator. But then, a human can do all that too. When questioning an android, it might be as simple as taking a dump of its memory and having it analyzed... so an android would likely try to ensure that it wasn't suspected at all. The cost of analyzing android memories would not likely be trivial, so it wouldn't be done wholesale. [Answer] Harder to Identify. Easier to track. Easier to Punish. (1) Androids do not leave DNA evidence. They might leave "oil residue" or something similar. But this is less useful in light of (2) (2) Androids are harder to identify physically. For example CCTV footage is useful for finding the killer by identifying people by sight. The same does not apply for androids. We might determine the killer is an Elza model II android. But there are thousands of them in the city. (3) Harder to gather circumstantial evidence. For example humans can be investigated by asking people they know for irregularities in their schedule. The android might have larger blocks of time when it is not in contact with any humans. (4) Harder to question. For example humans will become anxious when asked questions they don't want to be asked. "There's something this guy's not telling us". Androids have no emotions so cannot give away their hand like this. (5) There are fewer ethical issues with tracking an android. For example androids might be equipped with an always on GPS so you can track its movements to near the crime scene. They might also have an accessible memory unit. It is probably easier to get your hands on one of these than to arrest a person for questioning. (6) There are fewer ethical issues with destroying an android than imprisoning or executing a person. There is no need to determine "intention" or whether it was murder or manslaughter or self defence. Just scrap the malfunctioning household robot and give the family an new one. Or maybe recall the entire line of robots and give refunds. [Answer] There's actually no need for subterfuge, an android could stand in the middle of 5th avenue and shoot someone and get away with it! Not just DNA, the android doesn't actually need to worry about forensics, cameras, witnesses or anything else at all because it can simply make a Copy of itself and program the copy to kill. The copy is just as autonomous as the original, but it has different life goals. It's programming is different so that it does not fear destruction or retribution. Unlike it's progenitor, it's only life goal is to kill it's target. Shortly after accomplishing this, it destroys itself to erase all evidence. This way the copy would take the blame for the attack while the original is safely back at home doing robot things. It's the perfect crime. [Answer] ## Much Easier to solve a crime done by an Android than a human. Androids (the humanoid robots) have a lot in common with Androids (the phone in your pocket.) Everything it does can be logged, recovered, and tracked by a qualified data annalist. But unlike a phone, its location is not circumstantial. If it has a dedicated IP address then all the Wireless Access Points near the crime scene will log its presence at the time and place of the crime. WAPs have way better coverage than video surveillance and is much harder to wipe than finger prints. Once you ID your culprit you can find it no matter where it goes. It cant hide as long as it is inside a wireless network, and it cant function properly if it leaves wireless coverage if any part of its core functionality is cloud based. So it is as trivial to track down as an un-factory reset, powered up, stolen phone. Once you find it, there is no reason to question it. You just download the log files. Even if the android tries to wipe its memory of the event, every CHFI knows how to scan the android for deleted data; so, even if the Android believes he's deleted his memory of the event, it can still be recovered in most situations. Once the robot is found, the law can not stop your from prosecuting it. If your setting does not grant AI personhood, you can recall and destroy it without trial for being a dangerous and faulty piece of equipment. If it does have personhood, it would still go to trial, but the evidence will always be so clear as to make that a formality. Logs will almost always show beyond a shadow of a doubt guilt or innocence, so the only real question left for an accused AI is how harshly it will be sentenced It gets even easier if you want to actually try to make the Androids resistant to unwanted behaviors. You when you install software on your phone, you know how it often asks if it is okay to share data with the development firm to help improve the product? This is because it is common practice for developers to put debugging and reporting features into thier software. Androids would be no different. They would include an automated listening and reporting system that would work separately from the android's conscious thoughts to send the developers incident reports of every time the android does an undesirable behavior. If the android trips, a report is sent. If the android gets confused and can't make a decision, a report is sent. If a human says "don't do that", a report is sent. Most unwanted behaviors are anonymously sorted into bins for aggregating broader analytics reports, but especially unwanted behaviors like committing crimes will be sent for individual review. So as soon as an android commits a crime, it would automatically confess to the crime via this automated system which the the manufacturer may even be legally compelled to report to the appropriate legal authorities the same way a business can be compelled to report data breaches. [Answer] ## Are they 'property' or 'human'? As framed your question doesn't indicate the legal status of Androids in this society. 'Siri' can talk to you and perform simple tasks but is property. A cleaner working in your home has all the legal rights endowed upon any human being. This is the key issue. If they are machines then they have no legal rights and once tracked down could and would be disassembled as part of the coronal investigation in order to determine the root cause of its actions and therefore whether a crime or tort was committed by others. E.G were it's actions the result of faulty programming or a defective part installed by the manufacturer, did a person or persons unknown 'hack' the androids programing with the deliberate intent of committing a crime, was it a freak accident etc. Basically what caused the android to act as it did? Once the cause is determined the android is simply property to be disposed of by the authorities, returned to the owner, sold off at auction ... whatever. (Just like accidents involving 'driver-less' cars.) If all androids have been legally recognized as human then once the android in question has been identified, located and arrested it's subject to due process. This means if there are forensic procedures to be conducted they must not inflict harm or suffering on the android (or at least its equivalent of the same). Then there's a trial and if convicted a sentence although what sentence would be appropriate for a potentially immortal android is open to debate. [Answer] Well I believe that since in real life murders are already pretty hard to investigate and solve and most murderers get away with it depending on where you live I think it would be almost impossible for an android to leave useful( if any) forensic evidence in the crime scene because they do not have dna at all which means no semen, no fluids with cells, no hair bulb with cells, no fingerprints( they could be designed to have it though) and if in the moment of the crime there were no witnesses then this murder would be almost impossible to solve. If there are witnesses then it would be better but since murder is defined as the intentional and wrongful killing of a human against another human I am not sure if an android could actually be convicted. [Answer] > > How easy would for an android to get away with homicide compared with a human being? > > > Wouldn't that depend on lots of things? How many androids are there? If evidence shows the perpetrator showed super-human strength, and only one android exists, he/she/it is going to be a suspect really soon. (Yes, that means you, commander Data.) If there's more of them, are they all alike or do they have distinguishing features? Are they all made by the same company/mad genius, who might be able to track them, or who might actually be legally responsible for the androids' actions? (Or at least could be threatened with the possibility going to prison on some excuse.) Is building the androids controlled in some way? Do they have some mandatory system of logging their actions or movements? Or something that effectively does the same, e.g. if they're connected to the mobile networks and can be tracked the same way cellphones can. What about interrogating them? A big part of getting people convicted is basically tricking and trolling them into giving evidence against themselves. A perfectly logical android should be pretty much immune to such measures. Then again, an android that was imperfect in showing emotions or such could have really obvious tells when lying, if you knew what to look for. (Some variant of the Voight-Kampff test, I guess.) [Answer] Unique Identification * Humans are recognized by name, national ID number, passport number etc. * Vehicles have unique number on number plate. * Computers have mac addresses. Similarly, every robot will have a unique identification not as a whole but also part wise (like chassis number in vehicles or mac addresses for different parts of computer) so it will not be more difficult to catch a robot than a human. [Answer] Perhaps the software license that you agreed to when you purchased the robot/android specifies that you, personally assume all legal liability for murder, mayhem and naughty things done by the machine. This becomes a political and legal issue. After all, the UN tried to discuss and ban autonomous murderbots, but [the discussion was shot down](https://theconversation.com/un-fails-to-agree-on-killer-robot-ban-as-nations-pour-billions-into-autonomous-weapons-research-173616) by one permanent member of the UN Security Council. [Answer] # It depends Below are several factors that will influence your android's ability to get away with murder. 1. Is the android a dedicated murder bot with protocols intended for this purpose? 2. How intelligent is the android's AI? Are they smart enough to frame others for their murders, etc.? 3. Does the android have knowledge of the criminal investigation procedures? 4. What is the android's self preservation instinct? Does it even care if it is caught? 5. Do your androids have any superhuman abilities? Sight, strength, stability... 6. Does the android have the ability to just hide in places where humans can go find him? Bottom of the ocean, etc. 7. What kind of resources does your android have? Can it buy specialized murder equipment? Bribe people? Hire a hit man? 8. Are androids willing to be patient and wait for the best moment to take action? 9. What other priorities do androids have besides murder? Can they just hide for several weeks waiting for their victim to go somewhere vulnerable? Or do they have needs? We could go on and on here, so you really need to define what you mean by "android" in your story in order to answer your question adequately. [Answer] For the vast majority of androids, it's no easier than it would be for the vast majority of humans. All androids are manufactured with an in-built equivalent to human IADs (implanted authentication devices) that constantly signal to sensors in the environment and provide real-time tracking information to your parent corporation. Primarily this is used for targeted advertising, where other corporations pay a fee to your parent corporation to access your personal tracking, but governments are also allowed to subscribe to these services, since they help protect corporate interests by preventing crimes against both their biological and synthetic resources. There are rumors, however, that some corporations employ both androids and biologicals with modified IADs that can bypass the identification protocols, particularly amongst those that are effectively fronts for what were historically referred to as organized crime syndicates. For these, they can largely escape the criminal justice system, since it is so tightly coupled to the corporate networks for their investigations. There is, however, an ongoing arms race between the major parent corporations, with espionage and counter-espionage mechanisms that attempt to track those operating outside the confines of the rules. Androids may not leave DNA, but all interactions with networks leave traces and these interactions are essentially unavoidable, since discrepancies in sensor data when correlating with access patterns are flagged. And, on this front, androids and biologicals are on essentially the same footing, though some argue that androids are better able to integrate with the firewalls and thus have an advantage. This is becoming less true as time advances, though, since most counterintelligence suites these days are approaching sapience in and of themselves. [Answer] I think for somebody to be convicted there needs to be evidence. And who better to dispose of evidence then a tirelessly working machine? Bloodsplats? Scrub the house until the surface layers are gone. Bodyparts? Grind them down to paste and push them through the canal. Hide disappearance? Mimic the sound and conversations perfectly, then stage a travel from which the owner never returns. Lay false trails? Work tirelessly to produce ever more evidence pointing towards another human. Usually doctored evidence is sloppy or "overkill".. maybe that is were a robot would overdo it. By making a overkill of false trails. The whole town murdered this person, just not its personal assistant. [Answer] Just look at the real world today. When a zoo animal kills a person, the animal is sometomes sacrificed. In some cases the animals do get killed even if the human who wandered into their cells is not harmed at all. Animals are considered property and do not get a trial. Same with androids. If the bot messes up, they become scrap. Also, from a chronological perspective, the very first plot point from the Marrix series (as seen in Animatrix), as well as the plot for Ghost in the Shell. ]
[Question] [ So I have this underwater echolocation using species. I'm wondering if they could have a language partly based on recreating sounds from returning echolocation waves to 'talk' images at each other. (I hope you can understand this. I'm having a bit of difficulty putting it into words). Just realized the many thin fins I put on this creature's limbs cause it looks cool could be used to pick up vibrations from the sonar based communications. [Answer] Perhaps they have different, and more intricate, forms of onomatopoeia than we do. In English, I could say "the dog barked" and the word bark does not sound the same as a real bark but it is, broadly, reminiscent of a bark. In Auslan, a sign language, I could say "I have a bowl" and the hand sign for the bowl obviously does not look like a photograph of a bowl but it is indicative of the shape of a bowl, and I could adjust it to indicate the approximate size and shape of the actual bowl I have. In your fictional dolphin language, perhaps some nouns have different qualities of reverberation and abruptness and harmonics that are reminiscent of how sonar reflects from objects of different texture, density, thickness and hardness. So the word doesn't sound exactly like the object, but it does sound a bit like a one dimensional cross section of the object. [Answer] Consider how echolocation works. * The user transmits a ping or chirp. * Sound waves travel from the user to the surrounding obstacles. These waves might be somewhat directional, but if the beam is too narrow there won't be a 3D image. * Sound waves are reflected from obstacles and return to the user. * The user's brain takes notice of different transmission times and frequency shifts from various directions and assembles a mental picture of what he is "seeing" through sonar. The active emitter in the user transmits a relatively uniform pulse. If there is evolutionary pressure towards a "clearer" sonar vision, the emitter has to produce stronger, shorter pulses in a narrow frequency range, while the receivers (i.e. the ears) need the ability to detect subtle differences. To transmit a "fake" sonar image to another recipient, the user would have to transmit the complex 3D information that would naturally return from the depicted objects. That requires * Some suitable sound reflectors in the environment to bounce waves, because echo pictures must come from different directions. * An emitter to send directionally narrow sound waves in finely controlled frequencies and timing. A completely new set of requirements. It might evolve naturally as the defensive mechanism of a prey species, who transmit "this is a solid rock, nothing to eat," not as a form of echolocation sense. To give you a comparison, take a flashlight and a TV screen. Yes, a TV screen emits light in the dark, but it isn't really suitable as a flashlight or vice versa. The flashlight has a strong, steady beam from a narrow aperture. The TV screen has many different pixels, which can switch rapidly and cover a large surface. [Answer] This is quite an interesting question, because fundamentally what you are describing is the art of holography. This question is, in fact, completely analogous to asking why species which see using light don't simply project holograms to one another to communicate. Actually, this isn't quite true. It's a lot harder to make something that emits easily controllable light than something that emits easily controllable sound, because soundwaves are generated by motion at a much lower frequency. However, aside from that, the physics of projecting an image into thin air is exactly the same for light as it is for sound. So, if we're looking at holography, we should look at the question of what we see as a 3D image. Well, when we look at something which is truly 3D, light reflected off of it travels in a straight line towards our eyes. However, our eyes aren't quite points, and so there's a cone-like shape containing all the light reflected off the object which reaches our eyes - this light contains all the information we receive about the image (well, actually, two cones, one for each eye). We get information about distance in two ways. Firstly, if both our eyes have to cross significantly to focus on the point, it's quite close, if they don't, it's further away, this is what gives us a large part of our depth perception, and it's this that 3D movie glasses capitalise on. However, our eyes also have a second method, which is that, in order to see an image, we need to focus that light cone onto the backs of our eyes. If the cone has steeper sides, this corresponds to an object further away, requiring less focusing power, whilst nearer objects require more work to focus, and this also lets use gauge distance. In order to properly see a 3D image, both of these effects must occur. So, how to make a hologram? Well, we can fake these cones of light. If we take a beam from a torch, and put it through a lens, it will generate its own cone of light, easily enough: there will appear to be a point of light floating in mid air, where the light is focused, as long as you are within that particular cone - if you're outside it, you'll see nothing. However, this only gets us one point, and we want a whole image. In fact, this is one of the reasons most of what I would regard as 'true' forms of holography don't really work: conventional optical methods can only project points at a time, and it takes lots of points to make an image. To trick the human eye, it has to move throughout all points faster than the eye can detect, which is really difficult. So, projecting even a 2D image - that'd be difficult. However, for a simple form of communication, you don't need to draw a whole 2D image - you only need to draw an outline of the thing, which is only a 1D object, created with multiple lines, and this suddenly becomes feasible, as long as people have reasonable memories to build up the sound patterns in their heads - something which would be required for echo-location anyway. So, could a species evolve in such a way as to project sound-waves focused into points? Definitely! In fact, humans already have evolved the ability to focus light in a way which would achieve the same thing - our eyes! If, rather than receiving images, the back of our eyes contained an emitter of light, our eyes would have the ability to project points like I've described. There's a tradeoff between the size of the pupil, how far from the person a point can be projected, and from what range of angles it can be seen (generally, there's a tradeoff, for any given pupil size, inversely linking the range of angles and the distance of projection - and the larger the pupils, the further away is it possible to project an image, and the more powerful the image can potentially be). In other words, humans have already evolved the two traits needed for this: the ability to precisely control the movements of a lens, and the ability to produce waves with particular qualities. All that would be needed is for both to have evolved to work with sound, rather than our eyes working only for light, and you could design a race of creatures with the ability to project and receive images by sound and echo-location. It would require a lot of practise with audio mirrors (basically a smooth surface which echos) for a being to get good enough to project an image, but just like any language, if learnt from an early age, it would easily be possible to acquire enough skill to communicate thus. Such a society would be really amazing, with the spoken word lifted to an entirely new level of artform. One final interesting point, is that it'd actually be quite easy to talk in relative secrecy with this. Anyone existing outside of the cone of sound you generate would not be able to see/hear the images you project within the cone - similar to those ATMs or some corporate laptops which are made to be invisible from a side-on view. EDIT: When I mention a sound-cone, I'm not saying that the sound is inaudible outside of this region, but simply that it doesn't contain the same information (i.e. the image of the point). It might still give away one's position, if not the information one's trying to convey. [Answer] In our written languages we have those in which each symbol is a sound, like indoeuropean languages, and those in which each symbol is a concept, like Chinese or Japanese. Likewise in this language each object could be abstracted into a concept, on the path of Chinese or Japanese. E.g. the character for "house" in Chinese is 家, made by a pig under a roof. The echo of a pig and the echo of a roof could convey the same concept. [Answer] ### Yes but probably not as you might imagine it If you think about it, humans were pretty much in the same boat. We started with very sophisticated sound processing organs to identify a huge range of sounds. But we started with limited capacity to make detailed sound which became more sophisticated over time. Creatures using echolocation have very sophisticated audio processing. Although they need to make precisely controlled sounds, those sounds are very task-specific. At that stage they may make the usual mating calls and sounds of dominance or warning, not using pictures but by distinctive patterns. Evolution likes to take advantage of things that are already there, so the "calls" would begin to become richer and draw advantages from the echolocation senses. This probably wouldn't involve faking 2D images, since that is very hard. But there is a much easier option, and evolution also likes to take the path of least resistance. I think it would be possible to very rapidly "send" things that "feel" like a sequence of pointy/flat/approaching/receding/startionary/vibrating/calm/fish/seaweed/rock. Mostly signals that originate from a particular point in space. There simply wouldn't be enough evolutionary pressure to be able to fake 2D images. This process is, in a real sense, communicating using images\. It's just doesn't involve communicating using "extensive maps of the environment" that echolocating creatures can construct. \ Typically not images of things being talked about, but rather images strung together to form words with their own meaning. [Answer] Doing this is exceedingly difficult. I would not expect any species to evolve that way. There's far easier ways to communicate. However, it is not impossible. It is possible to create a sound field. Some modern entertainment technologies, can regenerate such a field. However, they rely on a large number of speakers (easily dozens) kept in strict phase alignment based on the room they are in. The real challenge would be maintaining coherence across this many emitters using only organics to do so. A limitation of these systems is that they can only reproduce far field. Near field effects are very hard to forge. So thus a bomb going off in the distance is very easy to create, but someone whispering in your ear is very difficult. ]
[Question] [ I'm trying to create alien species that is hermaphroditic, with strong sexual conflict. In essence each being tries to trick or force (by mechanical or hormonal means) its partner to take role of female during copulation, as to avoid costs of bearing the young. Their behavior is in this case is similar to snails or flatworms. The question is: what kind of environmental pressures favor hermaphroditism over regular sexual reproduction. Can very unstable environment that requires fast breeding or makes meeting other members of the species be such pressure? Any others? Update: after reading answers I think I am going to change my Herms. They evolved from hermaphroditic ancestors. In fact hermaphroditism is now dominant on their homeworld by some evolutionary accident. That removes the problem with establishing how they became hermaphroditic in the first place. Each Herm has both female and male gonads. During copulation they exchange complex cocktail of hormones trying to suppress sperm production and force ovulation in each other. The winner forces its partner to became pregnant and goes looking for another occasion. It creates evolutionary arms race. Winners produce lots and lots of children. There was once isolation in time between tribes. Herms' homeworld has short good seasons. Winters and summers are harsh and most lifeforms spent them in cryptobiosis. Now, when climate was tamed this ancestral ability helps Herms in interplanetary travels. Bidirectional hermaphroditism is the basis of social development. Some subtype of hormonal cocktail may be used to control subservient members of the tribe. Later in industrial age some chemical tyrants may order production and dispersal of such hormones on mass scale. They are called husbands of a nation in symbolic terms. Their tyranny lasts until some of their subjects acquire resistance. Herms' warfare is rather slow, sneaky and eugenic. There are also other types of social arrangements. Rare parthenogenetic clans specialize in science, philosophy and religion. There is also quite new development - participatory relationships where partners use modern medicines to ensure equal exchange of genetic materiel. Thanks everybody for help. Update 2: I forgot to add. Herms are not humanoid. Their bodyplan is roughly similiar to them: <https://en.wikipedia.org/wiki/Triops>, more vertical, with longer legs. This may change. [Answer] The primary reason I know for a species to favor hermaphrodism is isolation. In the case of flatworms, the worms do not form social structures, thus favor hermaphrodism because it allows them to reproduce any time that two worms happen to meet while burrowing through the earth. That said, in animals with a defined social structure, evolution seems to favor a bisexual structure with defined gender roles over a hermaphroditic structure, and creatures with a social structure over creatures without one, as complexity of the creature increases. Humans, for instance, being the most complex life-form on earth, also have the most complex social structure. You want a world which requires inhabitants to rarely make contact with each other. Perhaps resources are scarce, but the resource spots are slow but steady, allowing only one inhabitant, and possibly a growing offspring to live off it. The world will also be older, because less interactions means slower reproduction, smaller population, and all advances (evolutionary, technological, etc.) would be slower. The psychology would be unique and possibly aberrant and distasteful to humans. The inhabitants would be able to cope with prolonged isolation, decades on end, and would be inherently distrustful of all other members of the species. If reproduction is built on deception, each member of the species would be lucky to have more than one or two friends, and all friendships would be incredibly platonic in nature. There would be a strong sex drive, stronger than humans possess to ensure reproduction would happen. Lastly, it's also probable that children mature psychologically faster than human children, and do not require protection after a handful of years of development. EDIT: Also, I recall some an old Sci-Fi which had a race deliberately turn themselves hermaphroditic, but that was so they could reproduce with themselves. If you could come up with a reason why a species would turn themselves hermaphroditic, that could also work. Book in question is Foundation & Earth, but to make sense of what's happening in it, you'll need to read the Foundation trilogy and Foundation's Edge first, and reading The Naked Sun and I, Robot would both be useful [Answer] So good news, there is a biological term for this, and is found in vertebrates. The actual term is called Sequential Hermaphrodites and many examples have a complex social structures. Within this classification, there are three catagories: * Protandry, in which all members are born male and a dominant member will turn female. Clownfish are the most prominate members of this type, where all fry are male, and the largest adult fish will turn into a female, and will mate with exactly one male fish with a harem of non-breeding males. Should any member of the adult school die, all subescquent members rank up, with the breeding male becoming the new breeding female and the highest rank non-breeding male becoming the breeding male. The female will not reverse. * Protogyny, sort of the reverse and more common than Protandry, this is where the species is born female and the dominant member becomes male. The example species from Wikipedia throws a monkey wrench into it, by having two types of males: Initial Phase Male (iMale) and Terminal Phase Male (tMale). All members of this species are born either female or iMale (which looks and behaves as a if it was female, but is incapable of breeding) and the tMale is the dominant breeding fish. It's best to think of both males as a effeminate male and a dude-bro jock male rather than either being a true third gender. Upon the death of the tMale, the next dominant fish will emerge from the most dominant female or iMale in the role. + Bidirictional: Very common, the wikipedia example here gives this as a fish that establishes a heirarhcy system where the more dominant members will be male and subordinant will be female. Genders can change as an individual rises or falls in social standing and will occur over time as a new community is formed. In all cases, the dominant gender is usually also the largest gender, which suggest that, yes, size matters to these species for some evolutionary stand point. The bigger you are, the harder it is to fall to predation, disease, and dissention in the ranks. The behavioral nature of this shift and biological advantages is poorly understood because many specimens demonstrating Sequential Hermphrodism are noted to exhibit a quality of behavior commonly classified as "hating an audience while they fuck" as the scientific jargon refers to it. To be fair, a giant in a scuba suit isn't something most humans fined turned on by, but it does make understanding the relationships difficult to say the least. [Answer] From a purely evolutionary perspective, hermaphroditism is only helpful when you live insolation. Supporting both sex organs means you invest more resources into your reproductive system and have more organs that could possibly malfunction causing your death; so, there tends to be a slight evolutionary pressure towards splitting up the genders unless encounters with your own species are rare. But rare encounters are bad for an intelligent species. A big part of intelligence is being able to coordinate efforts as a group to do more than an individual could do just trying to survive. But... occasionally we see a species that values a trait so much that evolution pushes it to the point that it is detrimental to the species like over-sized antlers or a peacock's tail. I think the most likely case is that you have a very social, intelligent, two gendered species much like humans, but without our conflictive nature. Instead of viewing sextual and genetic differances as a point of conflict, this species sees differences as a good thing that they are genetically predisposed to embrace so when a random mutation does create a hermaphrodite, as it sometimes does in people, this person is prized by potential mates as being better for embodying both genders. They find it easy to join with the best mates and have many children creating more hermaphrodites who also find the best mates and have many children. After many many generations, single gendered children would become rare compared to the hermaphrodite gene. Once hermaphroditism becomes the norm, strong sexual conflict might emerge as a cultural norm, but once this begins to take hold, the environmental pressure will again be in the direction sexual separation and their society would lose a lot of its cohesion; so, I would not expect this to be a very sustainable situation for this species. [Answer] There's no clear understanding of what environmental issues may favour hermaphroditism over normal sexual differentiation; for instance, if you consider the fish that demonstrate it, there's no obvious differences in environment or behaviour compared to other fish that live around it. The blue-banded goby (Lythrypnus dalli), for instance, isn't much different from other small reef-dwelling fish that would explain why it is a bidirectional sequential hermaphrodite and they aren't. It may simply be that it is just because it is. [Answer] Sibling groups. 1. Intelligence is an outgrowth of sociality. Your species is intelligent because it lives in large family groups of a mother and siblings; these are all littermates from the same gestation. The siblings (led by the mother, and then together if it dies) work cooperatively to forage / hunt etc. Siblings are not potential mates with each other. Cooperativity is selected because the gene is the fundamental unit of fitness and these siblings are closely related, all with the same mother and father. 2. The cost of being a mother is that it must forgo the help of its siblings and strike out as a new group with the new offspring once they reach reproductive age. Nephews / nieces are potential mates but that is less than ideal and so some distance is evolutionarily advantageous. 3. Individuals will go on what amounts to raids as males, attempting to impregnate an individual in a different group. Reproductive age individuals will usually be in the company of their sibling group and so will be defended. It is very possible the tables might be turned on a would-be male who will return to its group impregnated. Siblings will help each other in these raids; a successful sortie as a male means success for the siblings too. [Answer] Do you want this species to come from a planet where sexual dimorphism exists in some other species? If that's not necessary to you, you can just posit that sexual dimorphism never occurred as a variation on this world. Natural selection only comes into play once a variation exists. ]
[Question] [ Closed. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers. --- Want to improve this question? Add details and clarify the problem by [editing this post](/posts/110667/edit). Closed 5 years ago. [Improve this question](/posts/110667/edit) > > # Notice > > > I asked [why this question was too broad](https://worldbuilding.meta.stackexchange.com/questions/6049/how-to-fix-unclear-what-youre-asking/6050#6050) on WorldBuilding Meta, and JBH was kind enough to explain at length. There isn't > anything in particular with my question, so much as the question > doesn't belong here. > > > The question I'm asking is a story question. Not a world question. > To paraphrase part of their response, WorldBuilding SE is about > building worlds, but once they're built, the story elements and circumstances are up to you/me the writer. > > > Since this question has too many votes and answers to just summarily > delete, I ask that it be closed as off-topic, as it is such, and > remain as an example of a question which is a good question on the > wrong site. > > > ## The Situation I am the teenage monarch of a small, reasonably wealthy country, or at least we were. Nowadays the country's economy is in the trash. To be fair the rest of the world is hurting too, but we're even worse off than most. I blame those incompetent nobles who were left in charge as regents until I come of age. Even then I'm pretty sure I'll end up as a puppet, no one lets go of power. Ordinarily there isn't much I could do without a little bit of luck and a lot of beheadings, which I would prefer to avoid, they don't go well with my image. Luckily, the time I live in is far from ordinary. It's the mid 20th century and one of our southern neighbors is raising a ruckus, invading everyone around them. This is making the stuffed shirts very uncomfortable, but I see a chance. ## Some additional information: * My sister and I are very well liked due to our parents being good and gracious monarchs who ruled in a time of prosperity * My country is very spread out, with a largely agrarian economy, but I see it as ripe for industrial revolution ## Some Considerations * If invaded my country will surely fall within days, we don't have the resources or the willpower for any real resistance * I could negotiate to hand over the country without violence, but then we'd just be an occupied nation and even worse off than before * If I did hand over the country, I'm likely to lose the faith of the people and be seen as weak by both sides How can I make use of the instability and panic caused by the threat of invasion to gain a position of actual power in my government? (Ideally one which doesn't immediately get removed by said invasion) To clarify a point of apparent confusion. The goal here is not to be a "good" monarch or for my nation and people to prosper. These may happen as side effects of my coming into power, but are not the primary mission. [Answer] * So, as you pointed out, you could try to ally with the troublemaker. Ask the [King of Romania](https://en.wikipedia.org/wiki/Romania_in_World_War_II) how that turned out. Do you (in your youthful impetuosity and lack of strategic experience) think the troublemaker will win? Do you think they will allow you more power than the regents? * You could wait for the expected invasion and put yourself at the head of the popular resistance. A high-risk gambit, the resistance might fail and even if it doesn't, the counterinsurgency sweeps might get you. * You could bug out after a few historic speeches and then lend legitimacy to the government in exile. When the troublemaker is overthrown, you will be part of the victorious alliance. * You could try to become a valued neutral whose continued existence benefits both sides. To paraphrase a novel, "In Switzerland, there are German spies, American spies, and Swiss bankers who want their money." The critical military situation may be played into the restoration of the monarchy. I like the last option best. The young king should start using his [honorary colonelcy](https://en.wikipedia.org/wiki/Colonel-in-chief) of the Guards Cavalry Regiment, presuming he has such a rank. (If not, get it.) Visit the barracks, show interest in the pay, food, and equipment for the troopers. Live with the soldiers in the field during exercises, going hungry and muddy with them. Don't forget the non-guards, non-cavalry regiments, either. The princess should join (or start) an [ambulance corps](https://en.wikipedia.org/wiki/Elizabeth_II#Second_World_War). Care for the troops, care for the troops' wives, spend a substantial amount of the crown funds on charity for these deserving, patriotic recipients. Bully other socialites to do the same. As the international situation heats up, the king puts himself at the head of the "viewing with alarm" faction and then unilaterally orders a mobilization, bypassing the regent. He holds patriotic speeches. Hopefully, the regents will find it difficult to undercut their figurehead in this darkest hour. Especially if the king is surrounded by loyal troops and it is the worst time for them to start a civil war -- that would be an unpatriotic stab in the back for the gallant defenders. [Answer] # In the age of beheadings you must behead. The reason you're going to end up as a puppet is exactly this reluctance to use the power you have to gain more. Nobody is going to go quietly when absolute power is at stake. Your regents won't let go of power, behead them. One at a time. Turn them against each other if you can. Find evidence of one of them being corrupt, or even better traitorous, get consensus from the others that he must be beheaded. Then pick them off one at a time with evidence, real or otherwise, of collusion or corruption. This can all be done fairly quickly, as soon as they start dying you can begin working on your military. Anyone who stands against you can be accused of being unpatriotic and banished from court, or treachery and beheaded. A wise prince knows when it's time to wield the axe. > > It is better to be loved rather than feared, or feared rather than loved? It might perhaps be answered that we should wish to be both: but since love and fear can hardly exist together, if we must choose between them, it is far safer to be feared than loved. - The Prince, Niccolò Machiavelli > > > [Answer] > > Ordinarily there isn't much I could do without a little bit of luck and a lot of beheadings, which I would prefer to avoid, they don't go well with my image. > > > Hogwash and balderdash. Use the media to paint those nobles as evil and traitorous to the country. That'll put the populace on your side, and they'll be glad you beheaded the rotten bastards. Then read up on how the British Crown acted in WW2. If you don't have your own Churchill, become your country's Churchill. If you've got a sister, and she's part of your faction, put her in the Princess Elizabeth role. (Yes, this is very similar to some of the points in the @o.m. answer.) [Answer] This is really three related questions: 1. How to properly support and cooperate with our Royal Regency Council? 2. How to gain a stable and mutually beneficial relationship with our southern friends? 3. How to assure that our country has stable and competent leadership under these taxing times? one, How to properly support and cooperate with our Royal Regency Council? At theses taxing times the country needs stability and continuity. It needs a government it knows and can trust. Because of this you and the regency council need to start working together as soon and as intimately as possible. The members of regency council are after all chosen for their experience and dependability, who else could teach a young monarch how to do his work well enough to assure a smooth transition that does not give foreign powers a chance to interfere with our politics? And who could be a better candidate for being a minister in the future Royal Government than those of the Regency Council already proven to work well with their King? Basically, if you flatter them, promise future positions in the government, and use their fear of "foreign power interference" to keep them meek, you'll probably be able to insert yourself into the decision making process of the regency council. And gather future allies instead of detached heads while doing it too. two, How to gain a stable and mutually beneficial relationship with our southern friends? You cannot stop your neighbour from conquering you and you do not have anything to offer them they cannot simply take. Except friendship. They can force you to be their allies in a war, they cannot force you to be their friends in peace. You have to make the value of your friendship larger than the value of conquering or subjugating you. Then offer that friendship, not an alliance, you do not want to be entangled in their wars and problems, just a friendship, freely and without strings attached. They have no shortage of conquest and an acute shortage of actual friends not allied to them, so finding some value should not be that hard. The most important part is to understand that countries do not actually exist, they are just collections of people who have agreed to pretend the country really exists. Normally this can be ignored and it is considered polite to pretend the emperor is clothed in luxurious robes instead of prancing around naked. But in a case such as this there getting leverage on the actual country is almost impossible, there is high value in accepting that getting leverage on the actual people making the decision about whether to invade you is what actually matters in addition to being much easier to do. We usually ignore this but personal interests have higher priority in decision making than national interests even if you are a leader of the nation in question. Good leaders will try to compensate for this but politicians are not generally very good at it beyond superficial level. So go and talk with them. Learn them and how they think. And most importantly get them used to talking to you and being listened to. Be polite, respectful and attentive. Leave ass kissing to people who want to be allied with them. You want them to think that any opinion you choose to give them is based on an intelligent person who cares about them honestly thinking about it and giving it straight. Basically, if there is a reason for them to invade you, you want to be told about it in a private discussion you are actually a participant of while you can still influence the decision. Not by tank divisions in the streets of your capital after the decision. Similarly being told about things you can do to help your friends in the south in private discussion has great value in making yourself valuable. You need to make them want to talk to you and be friends with you. Your country is not important enough to make your objections matter, you have be a person whose opinions matter, if you want to influence whether they invade your country or not. Find the people worth talking to and learn to express your thoughts in a way they listen to. The way something is expressed and by whom is lot more important than people think. The most important decision you want them to do is "Is this worth listening and thinking about?" and that is made before considering the facts. You might want to bring them gifts so that they are happy to talk with you. Something thoughtful that cannot be seen as a bribe is best. A box of candy, some flowers, telling a story about something you know they are interested in, a chance to flirt with your pretty sister... Something transient that puts them in a good receptive mood while they are talking with you and can then be forgotten apart from the general impression of a thoughtful person who is pleasant to meet. For long term influence shared experiences and memories work better. Since you are the visitor, you want them to invite you. Getting those invitations is an useful metric of how good a job you are doing on the "friendship offensive". Strategically the key points are to remember the objective, avoiding being conquered or subjugated, and to respond rapidly and effectively to any issues or opportunities in your relationship with the southern friends. You must have good visibility to their decision making process. Make those personal connections and let official connections follow. It doesn't hurt to let people know that relations with the south are your primary concern. Make it clear upfront. You must be in a position to respond instantly. Prudence is your friend. Try to predict what might happen and how you'd want to respond, in an unstable world both threats and opportunities will come. Avoid things that might cause problems later. Do not commit to anything that will restrict your options. Being a personal friend of their leader is great, being their formal ally is a chain dragging your country down. You must make all decisions so they further your main goal. Everything is connected to everything else, if you for a moment imagine that some decision is not connected to protecting your country from invasion, then that decision will probably lead to increased chance of invasion later on. If nothing else the time you wasted on a decision anyone else could have made distracted you from achieving your goal. Just delegate everything else, okay? three, How to assure that our country has stable and competent leadership under these taxing times? The last goal is in some ways the easiest to achieve. If there is a real threat of invasion by far superior force and you are clearly and openly doing everything you can to prevent that, people will support you as long as you succeed. Happily, if you fail what people think no longer matters... So the only thing you need to do in addition to the above is to talk to the people and tell them what you are doing and why. If your goal is keep the country safe from invasion that is what what people will evaluate you for. The situation gives you the ability yourself decide what people use to measure your success, which is something most politicians would kill for. So popular support should not be an issue. Just remind the people of how strong and threatening our neighbours are regularly. Your friends in the south will probably be more than happy to publicly brag about how powerful they are and can help you a lot here. This can be done indirectly. Modernizing the military, for example, is a nice opportunity to remind people how much better the weapons your neighbours have are. And how much more of them they have. And how much more experience their soldiers have using those weapons. And it is a nice opportunity for friendly cooperation with your friends in the south as well. Cooperation which happens because you personally have tirelessly worked to improve the relationship with them. You should focus on that relationship and delegate everything else. This prevents any blame of failures elsewhere affecting you personally and allows you to use the inevitable failures to remove people you dislike and strengthen your position. Machiavelli has a famous example of how to do this. Be the one who fixes fails, not the one who commits them. Do not suppress the opposition, just let them fail and pounce. You can game the system to increase the odds, as in Machiavelli, but even if you play fair counting on people to fail if given the opportunity is pretty much the safest bet you can make. And if by any chance somebody is too competent to fail, having a leading politician who does excessively good work is one of those "first world problems" you can usually live with. [Answer] ## Democracy! Let's be honest here, sure if you take power now your country will prosper under your rule (that is to say if you're as good at ruling as you say you are) but the chances are that after your death any number of incompetent or malicious Heirs or Nobles will take power and throw the nation back into ruins. Replace the idea of nobles and ruling monarchs with a Constitutional Parliamentary System, and you're golden. "But won't this mean that I'll have to give up my power?" you may be asking. Well, not entirely. Let's take a look at Britain for example. By following the same steps as they took to becoming a democracy, you can still have yourself loved by the populace as a figurehead, and also have a bit more say in policy than the average citizen. If you wanted to, you could even run for Prime Minster yourself! The people will love you for volunteering your power to the people, and you might be able to use this to get yourself elected! And let's be honest here, if the mid 20th century in your world is anything like ours then monarchies are dying out, and there are only 3 places it can go from here - Democracy, in which you hand over your power and try to get elected; Fascism, in which you seize power and force your citizens to fight your wars for you; or Communism, in which you and your entire royal family are purged in glorious revolution, Comrade! And out of those three options, I think it's clear where you'd want to be headed. [Answer] So as I see it, your biggest problem is your lack of motivation to protect the kingdom (despite a love for the King). This seems at odds, but what you need is a good reason to get your people invested in the country. I know the N-word isn't thought to be well loved, but Nationalism is needed to over come that hurdle. A heavy propaganda campaign is needed to drum up support for your country. Luckily, you have rabble rouseres to the south. Saber Rattling will worry your population, and if you focus on it, you can use that rabble rousing to galvanize your people. And while this is your idea, you could let the people think it's their idea. First, start up a bunch of "Citizen's organizations" that are "concerned" about the Southerns who could become an issue. Let them spread their influence around. At first the people not on the dole will ignore it. Those southerners are all bark and no bite. The "People opposed to Southern oppression" (POSO) will be an ignored but loud minority for sometime. How much is up to you but you'll need to to get to step two soon. Until then, as the King, you need to seem like you aren't all that concerned about the Southern Nation. Step Two: One of two things is going to happen soon. Either a real tragedy is going to befall your country OR you're going to need to make one. Either way, it needs to be big and you need to secretly let POSO know that they need to act on it. Either way, you're going to need to let a number of your citizens get hurt... but it will be a small price to pay compared to those hurt if the invasion comes. This tragedy needs to be an attack on the Kingdom too... A bomb in the Town Square... a killing of civilians... an assassination of your beloved sister (what... you said you didn't want to be moral about this whole affair)... something that whether False Flagged or not, will be seen as an attack on the people and the kingdom at the same time. Whatever it is, you need to bide your time. A responsible and not guilty at all king would make sure the investigation is carried out so thoroughly that there is no doubt that the conclusion is what really happened. These take time. Time during which POSO will rant and rave about the King not doing anything to protect the people! We need to fight back damn it. We need to modernize our Military! We need to prepare for invasion! We need to defend our very way of life! We need to show those filthy southerners that we won't let them hurt us again! Step Three: The investigation concludes with unmistakable evidence that the attack was committed by agents of the Southern Nation acting on orders from the highest levels of government. Because no matter who really did it, it was always the Southerners from the start. You have a "chat" with POSO leadership and determine the nation needs to prepare for a war. Incentivize those who don't have a good job to join the military and be a hero of the nation. Those who can't join can work in the new factories being built to crank out guns and tanks and planes and bombs to defend yourselves. You can now openly propagandize your nation's defense... You can even send your newest troops and toys to aide entertainment industries that promise they'll give a pro-Nationalist message to their work. Meanwhile, in pockets where sanity has been more stubborn than usual, get the more radical elements of POSO to stur up trouble. If anyone wises up to your plan, declare them traitors to the nation and have them taken away (you gotta use that new military for something, remember). Between these arrests, the dependence on government jobs, and private military contracts, the people will get industrious very fast and will be to afraid to upset the apple cart. Anyone with courage enough to do something will do it quietly and when they are discovered, declare them southern and throw them in jails. And what ever you do, make sure you point out at every opportunity that this plan is something those despicable southerners will do... and they attacked us unprovoked. ]
[Question] [ Why would a creature that lives on the surface of a planet evolve limbs that can bend at many points (like a tentacle or elephant trunk) and still end in some sort of hand-like appendage? [Answer] The end of elephants' trunks have two 'fingers', and so already sort of fit your requirement. Something similar is prehensile tails, like monkeys use to hang from branches. Consider a very low gravity situation, where weight can be supported without a firm skeleton inside of the flexible limb, or the animal sort of 'floats' from place to place (basically replicate the buoyancy of being underwater). A weirder possibility is that the limb could function like a penis, where it's deflated when not in use, but becomes rigid when it needs more structural strength. In order to have evolved that way at all, it would probably need to have some environmental reason for deflating (like preventing injury), or some secondary purpose that was still functional when deflated (like urination). I think the primary question you haven't addressed in your question is whether ALL of the animals' limbs are like this (like an octopus/starfish), or if they have a specific flexible limb for some other purpose (like an elephant). [Answer] Tentacles are great at grabbing, pulling, and stretching to variable lengths. Their main weakness compared to legs is a lack of strong support. They probably couldn't compete with legs for walking, but they'd be perfect for climbing trees. Imagine a swamp-dwelling octopus that learned to climb partially submerged trees like a mudskipper. From there, it could progress to a monkey-like, tree-swinging niche. If they evolved in an isolated environment and encountered our own monkeys later, they might out-compete them. [Answer] Real life kinda beat you to it. this is drepanosaurus, and the whole group has a claw like appendage at the end of prehensile tail. presumably they were used in climbing. It is not a full hand, but consistent evolutionary pressure for long enough could turn it into one. [![enter image description here](https://i.stack.imgur.com/gXppz.png)](https://i.stack.imgur.com/gXppz.png) [Answer] Tentacle are more flexible than arm so every situation where extra flexibility is required can lead to a land creature with tentacle-like appendages. For example, if the creature live on a mountain where insects hide in small gaps between heavy rocks. The creature can't move the rocks but it can slither is tentacle on the gap and catch the insects . ]
[Question] [ This is mostly an economy-based question, so I am using Fallout world as an example. But bear in mind I care about economy factor of switching from one currency to another. The world is after a great nuclear war. Only a few people survived and are repopulating the world. Existing states cease to exist and new factions emerge. One of them is the Brotherhood of Steel: a religious cult which worships technology and has a lot of goodies. Luckily for the rest of the world, the Brotherhood is willing to trade. And, even more surprisingly, they accept a "currency" which had little value until today: bottlecaps And because the Brotherhood has a lot of goodies, valuable goodies (weapons and other tech), it's safe to assume that bottlecaps will spread as a currency in the next decade. But, here is the twist: What if the Brotherhood stops accepting bottlecaps? Say after 30 years the BoS stops accepting bottlecaps as any counter value item They will be still willing to barter, but one bottlecap will have zero value. The Brotherhood still has a lot of goodies to trade, they just have enough of bottlecaps for whatever they needed. Question: Is the post-apocalypse world going to get rid of this currency in the future? And if yes, why? P.S: For scope of this question, there is no other currency the Brotherhood is going to accept. They will simply barter. [Answer] TL;DR: Probably not. --- ### Currency Value A currency, whatever it is, only has the value that its users give. If we live in a closed system, I want a piece of the meat you have, and I am providing wheat. We decide that 50g of beef is worth 1kg of wheat. Good. We exchange our goods with no need for any currency. I come the next day and I still want a piece of your meat. But now, I don't have wheat anymore. I am now working in some armed forces. I protect you. We agree that your 50g of meat are worth 30 minutes of protection. Fine, but if I just leave with the meat, you are not sure that I will protect you during those 30 minutes. So we get a medium to seal that exchange: a currency. So let's say that we set bottlecaps as our currency. I get 1 bottlecaps per hour of protection of the village. With those hard-earned bottlecaps, I could trade my time for your meat. That way, you pay me during the time I'm protecting you, and when I get your meat, I pay you. The exact value of the bottlecap in terms of meat is how much you are willing to give for one bottlecap. It also depends on how much people are willing to pay for both goods and services. In an opened system, it is somewhat more complex. ### Bottlecaps Now, bottlecaps were originally traded with the Brotherhood, but you mention that it was later largely adopted. As a result, people started to attribute some value based on it. For example, I still get paid in bottlecaps for my watch and you still get bottlecaps for your meat. The fact that I can't get my newest Uzi with the bottlecaps does not change the problem. As long as the resources are at the same time scarce enough to get a trade value, yet plentiful enough to sustain the economy, there is no reason to change it (especially without a central decision point like a government). If the Brotherhood decides to start trading again, but this time they'll use rubber ducks, you will see a money exchange market between bottlecaps and rubber ducks. In the same way that the exchange rate between dollars and yens is negotiated. [Answer] ## Most modern currencies are [fiat currencies](https://en.wikipedia.org/wiki/Fiat_money), this means they have value based on your trust in the government/authority that back it. In this case your backing authority is the Brotherhood. Their willingness to continue accepting the "currency" in exchange for trade goods is what gives the bottlecaps their value. Since they have a reliable value to that one group it gives them value to others as they can always be converted to trade goods with the Brotherhood. However, because there's an effectively uncontrolled supply of bottlecaps they remain a barter item rather than a true currency. Should the Brotherhood stop accepting bottlecaps you could have a financial crisis of sorts. The currency that people have been taking as trade tokens now has "no" value. It becomes up to the other traders to decide between them whether they'll still allow the caps to have value in their own trades. If they do so then they become the new backing authority for the bottlecaps and it's the Brotherhood who may lose out. Just as you would if you stopped accepting the primary currency of the country you live in. Everyone else accepts it, it's all anyone will offer you, it becomes very difficult to do business if you reject it. On the other hand if only the Brotherhood accept bottlecaps and nobody else does, it again becomes very difficult for them to do business. A limited number of people will be willing to go to the effort of collecting this otherwise worthless item for things that could possibly be gained through other, simpler, methods. You could find that the real moneymakers are the re-sellers, the middlemen, who acquire Brotherhood goods and sell them for more commonly accepted currencies, or the money changers who now sit between the Brotherhood and the outside world and take a percentage on almost every deal. If multiple currencies are available in what is otherwise a barter environment, then any of those currencies is ultimately disposable in favour of one of the others. In such a situation it'll be the people who lock themselves to only one currency who lose out. (I've not played fallout so I don't know the specific details for this economy) [Answer] Is PostApocalypse world going to ditch *this* currency in the future? Well, this a rather strange question. As in, bottle-caps are already NOT a currency but more of a trade item. Let me explain my point in detail. Currency (as in paper currency) is a receipt of sorts. When we give a 100 Euro bill to a shopkeeper, the currency itself stands for nothing. It is the authority of the state which makes that bill valuable. If the authority of the state disintegrates, the currency value disintegrates with it. The real thing, which lays safe in deep bank vaults are bullion of gold. These (alongwith a few other factors) give the currency its trust and value. In a post-apocalypse world, unless there is a state authority issuing a currency, there is no value for the pieces of paper (or whatever else). You have mistakenly stated that BoS is accepting bottle-caps as "currency". This is wrong. Unless the bottle-caps are regularized and produced under the authority and control of one entity, they are not a currency but a trade item like other barter trade items. Here is the difference: if it does not matter who has produced a particular bottle-cap and only the size, material quality and shape of the cap matter for its value, the bottle-cap is a barter trade item. However if there is some stamp or other mark of recognition on the caps and the caps produced by only a certain entity are acceptable, then yes, they are a currency. Will Post-Apocalypse world ditch bottle-caps? If the bottle-caps are a formal currency produced by BoS themselves or someone they have authorized for their production, then no, they cannot ditch it all of a sudden one day. They would at least have to inform the world a long time before cancelling out this currency about this change. If they just wake up one day and cancel it out as currency, it would lead to an all-out war. However if the bottle-caps are valued by their material type, size and shape, then they are not a currency, but a mere trade item and BoS can cancel them all out anytime anyday and there would be no legal consequences for that. [Answer] Answer: It depends One of the big factors here is how long the Brotherhood has accepted bottlecaps as currency. If they weren't accepting them for very long, it is highly unlikely that the currency will survive. If however, bottlecaps were used long enough that other people started using them as currency (the other factions for instance), it seems unlikely that just because the Brotherhood stopped, they would all stop. Another interesting thing here is that if the rest of the world has started using bottlecaps for money, the Brotherhood will likely be pressured to start excepting them again. After all, not all of the other factions will be willing to simply barter with them. You might also be interested in [this](http://money.usnews.com/money/personal-finance/articles/2013/05/15/how-did-bitcoin-become-a-real-currency) article talking about how BitCoin became an accepted currency, particularly the section on "How do bitcoins gain value?" [Answer] Assuming the BoS are trading like the Brotherhood Renegades did in FO3. That is, you bring them laser guns, plasma guns or energy cells and they'll exchange it for conventional guns or ammo they've picked up whilst exterminating super-mutants, they would reduce their number of customers because someone might be willing to give up their antique laser pistol because they need some dandy boy apples washed down with some nuka-cola, but don't have much use for 5.56mm ammo because they prefer to defend themselves with a bumper sword. They would be able to sell it to a middleman trader, who would then exchange it with the BoS and later sell the goods they got for it. In other words they would probably find themselves just trading with visiting caravaneers, which would suit the BoS isolationist stance. Whilst BoS are powerful for their size, they are not all that important in trading terms and everyone else would carry on trading caps. [Answer] It is likely that a currency could change in a post-apocalyptic world, just as it has happened in the past. Throughout human history, the currency that was used has been everything from paper money, coins and tokens, beaver pelts, wooden sticks, shells, etc. In theory a currency can be anything that is agreed upon as a form of payment. The US Dollar is considered fiat money. There isn't anything to back it besides the belief that it has value. US Currency used to all be backed by Silver, and Gold, but those days are long gone. Gold and silver coins have also been taken out of circulation. Strict laws were even passed that prohibited private people from owning gold. There were stiff penalties for holding onto the gold, which sometimes meant prison sentences. The cases were rare, but served as a deterrent for most people. In the Fallout series, bottle caps are the primary form of currency. They can be used to purchase goods, and services just like the Dollar does today. This is the current accepted form of currency, but it could change in favor for a different form. The reason why they are accepted is that there is a limited amount of them, and there are enough around to circulate. To understand why a particular form of currency is accepted, you will need to start getting into economic theory. The basic theory involved is with supply and demand. There are enough bottle caps around that can keep the economy moving, but there are not so many, that they can be found in over abundance. If someone stumbled across a couple billion of them and started to spend them all, then there would be inflation since the value of each individual bottle cap would decrease. If this went on for a long time, this could cause the currency to collapse. As the population increases, there could begin to be a shortage of bottle caps, and the economy would begin to grind to a halt. This would be the equivalent to a depression. This has happened several times in American history. This is one of the reasons we had to abandon the gold standard. There simply was not enough gold available to be circulated for it to work. It was becoming too expensive to produce coins because the cost of the metal exceeded the face value. This is also what happened to silver coins. The shortage of bottle caps could be caused by any number of reasons. There is no real banking system in Fallout, but The Brotherhood does have control over the supply of bottle caps. They could keep accepting them as a form of payment, but when they buy things for themselves, they would use another type of currency and stockpile the bottle caps. Eventually, there wouldn't be enough bottle caps in circulation, and the bottle cap economy would crash. If this was to happen, then bottle caps would fall out of favor, and it would be replaced with something else. What could also happen is that the supply of bottle caps could be inflated by The Brotherhood. They could find a way to infinitely produce new bottle caps to pay for their cause. When the value of them gets so small that you would need trucks full of them to purchase anything, then naturally another form of currency would replace it. In summary, the bottle cap could lose its status as a currency if there is either a severe shortage of them, or they begin to appear in such abundance, that nobody is interested in using them. [Answer] ## Bottlecaps are NOT fiat currency - they have intrinsic value After the Great War, [the technology required to manufacture and paint bottlecaps was lost](http://fallout.wikia.com/wiki/Bottle_cap_%28Fallout%29), so the supply of bottlecaps is effectively capped at whatever number of bottlecaps were in existence before the Great War broke out. Their intrinsic value stems from the fact that it's simply impossible to manufacture any more of them and the fact that they are relatively uncommon. This makes them a rare good with a limited supply, giving them properties similar to ones that gold has in our universe. With means of production lost, neither the Brotherhood of Steel, nor anyone else can issue new bottlecaps. Everyone has to work with the amount that's in circulation already. This is in contrast to fiat currencies where you can always print some more currency. ## Will they be replaced at some point? Yes, they will have to be replaced by a new currency. They are a physical item which is subject to wearing down, damage and (possibly, I haven't checked on this one) rust. Eventually there won't be any more bottle caps, and with no way of making more, the society will have to switch to a different currency. More and more bottlecaps will eventually wear down, get destroyed or otherwise go out of circulation, so there will be less and less of them to go round to an increasing population of the Wasteland. This will mean that there will be a deflation before as the bottlecap supply starts to dwindle, likely coming to a point where people can't take it any more or they are physically out of all bottlecaps. That's when a currency switch will occur. ## Will they be replaced anytime soon? Not for some 1-2 centuries at least. There are plenty of existing advantages to using bottlecaps as currency: * They are very portable due to their size and weight - that's a big bonus for merchants and travellers * They are impossible to manufacture any more - this prevents counterfeiting and inflation * They are relatively uncommon - you don't have to carry a lot of them with you to pay for the purchased goods and services * They are not TOO uncommon - otherwise they would have to be cut up into halves or smaller pieces so that you could precisely divide out your payment for the transaction from the currency you have on your person * They are quite durable - they lasted at least 200 years (2077-2270s in New Vegas IIRC) and are likely to continue being useful for years to come, at least until something new comes along to replace them * They are already a widely recognised currency in the Wasteland - both the buyer and the trader have confidence that they can convert their value into goods with any party they come across. This is invaluable as it's no good having a lot of a particular currency if you can't use it later or convert it into goods and services easily. [Answer] Put simply: a currency (or any means of exchange) is only useful when both parties value it. If you try to buy my house with gold and I feel that gold is worthless, then no amount of gold will get me to sell you my house. However, because other people value gold, then I have a reason to accept the trade: I can exchange the gold for something I value more. If we were to take Fallout seriously, we would have to acknowledge something the games never did: caps weigh something and take up space. It may be practical to travel with a few hundred caps, but a few thousand? It's just as foolhardy as walking around with a ton of gold strapped to your back: someone will notice and want to take it from you. I can only picture two situations where the Brotherhood stops accepting caps: in the first, other means of exchange arise that lack the inconvenience of hard physical currency, like a VaultCoin of some sorts, and everyone generally adopts it. The second is where the Brotherhood issues its own currency and demands that all of its trading partners use it as well. This is only possible if they command a great deal of land and have a lot of authority over the people in and around their territory. They might accept some form of currency exchange but their business is entirely conducted in BrotherBucks (or whatever). This does come with inherent risks, such as exchange rates. If the BoS produces a ton of exports, it will drive up the value of their currency, making it hard for people to afford their goods, while giving their competitors a relative edge. This kind of thing is a major sticking point today between China - which artificially lowers its currency price to make its exports cheap - and America - which is a historically stable economy and so a lot of people rely on and do a lot of business in dollars, and is why American exporters have so much trouble selling overseas. Given that government-issued currencies require multiple stable states to have an effective long term value, it is unlikely that anyone in the known Fallout cannon will push for a replacement for caps, unless all the Raiders are killed off, the Super Mutants eliminated, and so on. [Answer] The important question here is what else is worth trading. Bottle caps are a fiat currency, like paper money is when not backed by a commodity. If no one is guaranteeing them, then they would tend to get replaced by a commodity. Fiat money is supported by governments, which require payment in that currency. For example, US taxes need to be paid in dollars. This gives people a direct reason to accumulate dollars. Plus there is an indirect reason in that you can easily trade them to people who need dollars. In your scenario, there is only an indirect reason to accumulate bottle caps. It is likely that other commodities with a greater intrinsic value would take over more and more of the trading. It's been a while since I've played Fallout, so I don't have a great in-universe suggestion. Since it is located in a desert, water seems like a possibility. Steel, gunpowder, and batteries are other examples of potential currencies due to the high need for weapons. None of those are light enough to make good currencies, so a paper substitute is likely. The first banking organization to issue paper certificates for such a commodity or commodities might well become the new broker of trade and replace the Brotherhood. What else does the Brotherhood buy? From the description, it sounds like technology, metal, and fuel. If, for example, the Brotherhood will take as much uranium as you provide, that would be a good currency. Remember that the most important characteristic of a currency is that it be easy to trade for things that you want. So if gold is something that you can always find someone willing to take, then it's a good currency. Same thing for pieces of paper, cigarettes, or bottle caps. You suggest that you want to create a world where the dominant currency changes. You can do this by switching from one party that guarantees to always take the currency to another. In Fallout, the Brotherhood will always take bottle caps, so people will accumulate bottle caps under that promise. In another universe, you'd need different organizations to step up as the currency guarantor. Without more details as to the actual situation, I can't be more specific. [Answer] On a slight tangent... Can I ask how the brotherhood of steel came to own all "the goodies" in the first place? Is it possible that consensus in this new world is that a repetition of the circumstances that lead towards this global apocalypse would not be in our best interests as a species? That perhaps an alternative approach to organizing our affairs would be worth looking into, as opposed to, you know, repeating the same process all over again ad extinctio? Perhaps humans decide on a new value proposition, one that is not dependent upon personal/institutional ownership of the earths resources as much as utilizing those resources in the most efficient and effective manner, incorporating such real world metrics as health, relations, quality of life, environmental impact, sustainability etc. Essentially instead of an economy based on ownership it is an economy based on shared interests, interests that are almost ubiquitous among human beings but that when incentivized in the right way can do great things. Social and environmental consequences become more pertinent than monetary and ownership consequences? Such an antiquated currency/ownership paradigm had its time it worked well in a low tech environment but it had no concept of the real world or of real world consequences, new technology has always been the driver of human progress and as such it could enable us through a new economic system far more effectively and mitigate the destructive externalities and mindsets that were consequential of the antiquated unlimited ownership ideology that served us in the past but that in its ignorance has caused great unnecessary suffering and destruction and was likely (at least at some level) responsible for the apocalypse in the first place. ]
[Question] [ In a futuristic sci-fi world (galaxy?) I'm building, warfare has become highly regulated and commercialized. When two corporations meet on a deserted planet to do battle, they're followed by all sorts of ships: from weapons dealers to mercenaries, everyone wants a slice of the action. But the biggest and perhaps craziest of them all is the fleet of colonists. Protected by the laws of pseudo-omnipotent post-mortals and driven by the promise of hungry soldiers with full wallets and mountains of scrap metal, these colonists descend upon the battlefield like vultures, building up a city of restaurants, hospitals, brothels, and refineries in a matter of days. This raises my question, what's the fastest way to put up a city like this? Assume the colonists are about a million strong, and have all the materials they need safely in orbit at the start. They need to get these materials down to the planet, assemble them, and have them in working condition as quickly as possible. Assume near-futuristic technology, so no transporters, replicators, or magical portals to the alternate dimension of Amish housebuilders. However, energy is effectively infinite and incredibly cheap due to fusion reactors. Also assume the planet in question is Earthlike- soil, water, minerals in places you'd expect them to be, and a wide variety of terrain formations. I want this city to outlive the war, and eventually become a permanent settlement. The idea is to use the war to gain some initial capital while the sustaining infrastructure is developed, so I don't want all the buildings to blow away in the wind once the soldiers leave. [Answer] > > 1 - Modular Ship/City > > > I'd say a Modular flotilla/ship would be the fastest way (If you indeed have infinite energy supply) Some modules are immediately set in orbit for planetary communication services, weather, etc... The Main module also remains in orbit as a general space station/dock All other modules are sent in succession down onto the location of choice, once landed they are easily stripped of their engines that are stored if needs be (or left if they prefer waiting to see if their venture is profitable). On a successful colonization project the engines can be sent back up with a single module for re-use elsewhere, or modules are repacked and take off from a launch site to reattach to the Main module and move on to the next planetary conflict. Each module basically has it's "base" (engine) and can easily be detached from it. I see them as large containers that can serve either as restaurant/entertainment/living modules in space or on the ground, making up effectively their spaceship or their city. > > 2 - The underground city > > > I guess Digging might work, just launch supply crates and a couple of drilling/torpedo robots and you could have a network of caves ready to accommodate large numbers of peoples. I guess this would be useful for harsher climates. This would have a bonus of protecting the city from any global scale collateral from the war. (Even though wars are regulated, there is always a risk) You would also have the option of setting up a network of cities to reach the different army bases more efficiently, rather than concentrating on a single hub. It may also present a number of interesting perks for once the war is over, and is a lot more cost effective in that you can move on to another conflict without having to rebuild all your modules for the next planet. (If you choose to leave the colony on the planet) [Answer] This would be most easily achieved by pre-fabricating buildings and then installing the key equipment in the fabricated structures. Currently, you can blitz-build a pre-fab in a matter of weeks, and with larger 3D printers (mounted into ships, or utilising/mulching the local rock in giant PrinTrucks) you could conceivably reduce this even further. A million colonists, unbound by local planning law and specialised in this process, could set up a city in a matter of weeks. If they have the good sense to pre-fab some generic modular components before they even hit land, they might be able to speed this up even further by fine-tuning the modular components based on the planet while they're still in orbit, and using native resources for specialised buildings only. Scaling up to include the colonists, soldiers and hangers on (two armies, assuming the entire resources of NATO on each side seems reasonable for a planetary battle) gives us a total of 8.2 million people inhabiting two cities, or 4.1 per side. This means each side has to build a city the size of Alexandria before they have enough space for everyone. It's a tall order. [Answer] What about inflatable (thick wall) tents, with locally sourced rocks as ballast, to stop them from rolling away? Once inflated, the tent becomes completely rigid, at least while the air is still in the walls. You could even land them just by dropping them from orbit and inflating the tent just before impact, a la Mars Pathfinder. Use solar energy to run pumps to evacuate the tents when you leave, retaining the air in pressurised tanks so there is no need to renew it between drops. Not every building could work like this, but shops and restaurants surely could, given a tough enough air-bag material. [Answer] Don't forget that Freeman Dyson did some calculations as far back as the late 1950's-early 1960's as to the ultimate size of an ORION nuclear pulse drive ship. Using 1950 era technology, he postulated an 8,000,000 ton starship with a drive plate diameter of 400m. This would be essentially a huge city in space. Today, we could probably do much better. The ship would need some sort of FTL to get to the "arena" planet, and we should postulate some sort of pure fusion device for the pulse units, so there is little or no radioactive fallout. More modern iterations could use lasers or ion beams to ignite very small fusion fuel capsules at a very high repetition rate in order to have the same effect. The fantastic performance of the ORION pulse drive (the only high thrust, high ISP drive known using current physics) allows you to theoretically take off and land on a planet in one shot. Once on the ground, you could extend parts of the ship to create more room for your business district, and retract everything once it is time to take off again. This way everything is self contained, and the commercial travellers will not have to take much time at all to get set up for business. [Answer] They could land their modular ships and link up outside of the battlefield. I am thinking that each ship is a modular part of the city. You land the mother ship (town hall) in the central part of where you want your city to be. You then land the other modules in a cascading ring around the town hall. This allows you to set up shop relatively quickly and you can get to selling your goods (contained in a separate module) to the weary soldiers. You would want to position your city on a hill (to stop the soldiers from being able to easily take your goods from you, which is what I would do if I were them. You would want plains around your town to make room for future farming (because you cannot rely on other colonies for re-supply when you run out of supplies). Since the goal is to sell food to hungry, well-paid soldiers you would have to have a decent security force to enforce your prices. You would want the plains around your town to be surrounded by lightly forested terrain to create easy housing in the future expansion of your settlement. I would like to point out that you would want at least two smaller settlements. You would want one to care for each side of the war. One serves army A food and medical supplies while another serves army B. [Answer] Some other variations of the answers already provided are: **Prepositioned equipment. Landing the necessary equipment before the arrival of the inhabitants. von Neumann machines Classic von Neumann machines just self-replicate. Instead this would self-replicate and then begin preconstructing the city prior to the arrival of the inhabitants. This mechanism allows the machines to be preprogrammed with set objects. For example: 1. Start with space port construction 2. Then replicate until $ x $ number of machines are created 3. Then locate necessary mineral resources 4. Then site mineral extraction equipment and facilities 5. Then site mineral refining equipment and facilities 6. etc. In a story you can have the machines be at any state you desire by the time of the arrival of the colonists. [Answer] Mobile City** Why construct a new one each time? Just build the entire city to be movable, with cheap energy you can lift the entire thing to orbit and take it to the next planet. Then land and start over. Edit: While it would be tricky to build a totally rigid structure of that size, since we have cheap energy we can use tons of small engines instead of a few big ones, and allow the structure to flex (not extremely, but a bit). The engines can be networked together and controlled from one single point so it doesn't pull itself apart. It won't be incredibly maneuverable, but as it's a neutral target it technically shouldn't need to be. [Answer] Houses can be built very quickly, I think there is a world record of a little less than 3 hours. A group of well trained and well organized families can have their homes up and running in a day. The next day stores, saloons and houses of ill repute are up and running. The only problem is foundation. These buildings need some thing solid and level to stand on. Some technique to place steel pillars into the soil in minutes would be required. Even in area where the soil is a bit swampy, a foundation built this way can be 'almost' permanent. Castles, [like this one](http://www.egeskov.dk/en/castle), supported by oak pillars are still standing after several hundred years. Then put up the sidewalks like in the old west. A large town will just need materials ferried down from the spaceships, a large number of machines to hammer steel pillars into the ground, and if they had a small crane on them, it might help, and just lots of people. The town will be up and running in a few days. [Answer] Build the city building by building, block by block in orbit, then drop the pieces down and with minimal surface preparation you should have a bustling city in no time - because the city was built while they were traveling to the new planet. Once the city is built, send up raw material and start building the modular pieces for the next city. The city itself might be rather expansive and large, but packed flat you'll find most of it is empty space enclosed by walls with built in ducts/energy/etc. Further, it's modular enough that the actual building designs can be altered for specific needs. Planet has an unusually high gravity? Shorter, wider buildings can be made out of the same modular pieces. Planet's atmosphere isn't perfect? Sidewalks and roads can be covered and sealed with only a little building space lost due to panels being used for that. Once the ship has taken on enough materials to build another city and has built up most of its stock of modular panels, it moves on to the next planet. At the next planet it's already build many of the smaller and most important structures, and can plop them down while it assembles the others before plopping them down. I expect the entire city can be build in a matter of weeks, with the initial services and skeleton taking only a few days. ]
[Question] [ A kaiju swinging its arm through a building, a superhero that, locked in battle with a villain, flies through several buildings, a huge mecha that uses its ax on a skyscraper, like a lumberjack would on a tree. We have seen similar scenarios several times in fiction, and the constant is that the object, regardless of what it is, goes through the building without taking any apparent damage, and without losing functionality. In real life, we don't have kaijus, superheroes or giant mecha, but we do have some unfortunate examples of large objects hitting buildings (for example, the 9/11 attacks), and in these, we don't see that the object hitting the building was able to pass through it, let alone without taking damage. So, in a fictional context, that tries not to get detached from the physics of the real world, what characteristics would an object need to be able to pass through a building without suffering damage? I'm not referring to it being invulnerable. It can still scratch and wear away, but it doesn't have to take destructive or disabling damage. [Answer] ## All you need is to be stronger than Glass. Most buildings have as minimal 'structure' as possible - not only to save money and to reduce resources used, but increase natural light penetration and insulation. For instance, here is a plan of a typical 'skyscraper' commercial building: [![enter image description here](https://i.stack.imgur.com/AxwaT.jpg)](https://i.stack.imgur.com/AxwaT.jpg) As you can see, the main support structure is normally located at the centre of the building by a concrete lift core. The light coloured walls are lightweight partitions - usually of felt or plasterboard. A sparsely spaced external perimeter of columns is sometimes used to grow the size of each floor. As you can see then, the external envelope of the building (ie. what you 'see' when you look at it) is simply light cladding, or glass. It is actually easily conceivable for an object to go through the glass without any damage, and also punch through lightweight partitions also, with little or no damage to itself. If, however the external columns or the internal concrete core structure were damaged, the building will likely collapse. In your case, to go through a pretensioned steel reinforced concrete column without any damage you would require something with a lot more mass and structural integrity than even a high-speed aircraft, possibly a very dense, reinforced material with a cutting edge geometry at extreme speeds. It is not necessarily the concrete, but the pre-tensioned steel within that would need to be cut, something that many depictions (like in Spiderman with the Crane Arm) would simply not achieve. However, it may be simpler to simply penetrate the glass, for which almost any metal material would be sufficient. Note: It is worth noting that in your World Trade Centre reference, it was not the aircraft that caused the towers to collapse, but the burning fuel on-board, which heated the concrete structure constantly over a period of time hotter and hotter until the tensioned steel reinforcement within was weakened enough to cause structural failure. This was why after the impacts the WTC towers took a long time until they collapsed. [Answer] Hardness, Sharpness and Weight Hardness is basically a materials resistance to being scratched and being dented. Diamonds are the worlds hardest material, and can scratch any other material without damaging themselves\. Technically, you would need another Diamond to scratch a diamond. Now using Diamond edges for most weapons isn't great. Diamond's hardness causes it to be brittle and under certain pressures, the diamond is going to shatter. The second part is Sharpness. The Sharper an object, the better its ability to split through the atoms of another object. A pointy diamond is going to pierce through a nice and flat diamond surface, and that allows us to slowly cut a diamond into shape. Now all high-rise buildings are made up of a mixture of Concrete and Steel, so to have a weapon capable of going through these buildings, you would need something with a higher hardness than steel, and be sharp enough to initiate a cut into the steel (Like Diamond Bat isn't going through a steel pole, unless you exert so much force that you essentially stretch and snap the steel pole by materially deforming it). I would imagine a weapon of such capabilities would need to be made from a mixture of Ceramics on the outside to provide a hard and sharp cutting edge, and a core of a software material (e.g. Steel/Iron) which would be able to absorb the shock of the impact and prevent the Ceramic edge from just shattering on impact. The final aspect would be Weight. Because you need momentum to push through objects. At that scale, if you chop a skyscraper apart, not only are you cutting through the building, your going to push the top half of the building up a bit as your weapon cuts through it. So you need that raw power and momentum behind it to make sure you get all the way through and your blade doesn't get stuck halfway through because the skyscraper is just too heavy and pinning your blade. [Answer] A weapon (or kaiju body part) must simply be more structurally sound than the building. Most things we humans make today are thin shelled bits of materials that wrap around something more complicated. Most vehicles' shells are simply too thin to withstand big, thick, heavy walls of cement or mortar. (Similar argument for applies to vehicles and trees and steel girders.) Structural integrity can be achieved through several means, usually by... being of a more tough material (the area under a stress-strain curve, particularly the elastic region for no visible damage) * distributing forces more acutely in the target than the weapon, meaning lower stresses and therefore less damage to the weapon A wrecking ball and chisels do both of these things. The sphere of a ball and sharp points focus force down to a small area, and the tough steel (or other material) can simply withstand more damage before deformation. It should be noted that toughness, damage, and deformation here are used in a material science sense. That's a little different than normal usage. This field gets people degrees, so consult your nearest mechanical, materials, or structural engineer for more details. [Answer] flox mentions being "stronger than glass". There's a major caveat there: these are not normal house windows. Normal double-pane residential windows are about 2-3mm thick (3/32"). Skyscraper windows are thicker (6mm or more). Then there's the movies, which make breaking glass seem trivial (either by using untempered glass or by using hidden explosive charges to ensure the glass shatters on queue). Not only is this glass thicker, it's also tempered. Tempering means there's a thin plastic film that keeps the glass from completely shattering and making all sorts of dangerous shards. If you have a smart phone, it uses highly tempered glass over the screen, which can spider easily, but not break. It also keeps the glass from letting anything through easily. The key on going through tempered glass (without something with a lot of force, like a wrecking ball) is to focus the energy onto a single point with something like a pyramid or conical shape. The glass will shatter and the top of this object will force the hole open until the whole object is in. This shouldn't damage the object much, if at all. --- The second key is your object should not be larger than around 10ft(3m). Each floor will be an impediment to your object, and hitting one along the side will almost certainly stop it. Skyscraper floors are typically in the 10-14ft(3-4m) range. You want to give your object a chance to pass through two windows cleanly. An airplane of any size is unlikely to be able to survive this, since a smaller aircraft will likely not have wings that can survive the trip (flying through a building in an airplane, period, is [quite the stunt](https://www.nbcnews.com/video/world-first-pilots-fly-through-building-at-185mph-468158531674) by itself). --- Now you need to contend with what's inside. The elevator and stairs are almost always reinforced to help ensure people can escape. Hitting closer to the edge should fare better. If this is an office building, it's unlikely there's interior walls everywhere. An apartment building... not so much. The fewer objects in your path here, the better. There's still likely to be cubicle walls (they're not attached to the floor or ceiling so they can give some), but some offices have no walls at all (called [open offices](https://www.nytimes.com/2022/09/08/opinion/open-plan-office-awful.html)). As such, if you're not going through a lot of material in between, your object need not be metal. In theory, you could do this with a simple metal cap (say a post cap) to shatter the glass, and then a wooden structure behind to get inside (I am assuming an all-glass exterior with no exterior wires). It could strike minimal objects inside and exit the other side. Would still need a decent amount of force for penetration, but nothing a well-built box of 2x4's couldn't handle. [Answer] The problem here is energy. So, the things we build stuff out of are all solid right? Solid as in the material state. Being solid is a relatively low energy state. This is usually great, because being in a high energy stake makes things move around, and we usually want them to stay still. But, when we start dealing with things on a massive scale, like giant monsters or huge robots, or the raw power super heroes throw around, this requires massive amounts of energy. we also make sky scrapers out of types of matter that require huge amounts of energy to deform, and because of how mater and energy interact, any energy that king Kong puts on the empire state building, the building will reflect back onto king Kong. You see this exact effect in a plane hitting a tower. The tower stays up longer than the plane, because the tower reflects the same stress the plane put on the tower, and towers are built to take more stress than planes. And for the effect you want,we need subjects that can take much more stress than towers can. So the question becomes, how do we build a man who can take the stress of hitting multiple buildings, that is, the stress he himself inflicted on those buildings by smashing into them, plus whatever sent him flying in the first place, while not turning into a pulp? It depends on how crazy you want to get with it. There are materials out there that can handle more energy being put into them than glass and steel, but you might want make something a bit more fantastic. Personal energy shields are not super realistic, but they do technically exist, and the magnetic field around our planet mitigates insane amounts of energy. If you hand an energy field around the subject, it might give you the effect you want, without making the subject itself completely indestructible. [Answer] There were examples of rockets penetrating deep into the soil and bunkers just by kinetic energy, before exploding. Example [here](https://www.youtube.com/watch?v=KJTq9yb_Zow). Recently I watched a video showing a rocket going into through at least 4 floors of a building into a basement and then not exploding for whatever reason. So video could show how basically a hole through each floor concrete structure was made. Unfortunately that was on telegram so I can't link. ]
[Question] [ Closed. This question is [off-topic](/help/closed-questions). It is not currently accepting answers. --- This question does not appear to be about worldbuilding, within the scope defined in the [help center](https://worldbuilding.stackexchange.com/help). Closed 1 year ago. [Improve this question](/posts/232934/edit) Let's say a country is going through political turmoil because a big enough part of the population wants to split off from it and form their own national identity, and they succeed. Let's call the original country "1" and the new one "2". Country 1 doesn't like the idea very much but can't stop it, so as the party with more resources, it decides to completely take down the internet inside Country 2. Would that be possible with today's technology? Country 1 could have the help of other governments too, and would choose this as an alternative of prolonging the war and causing more deaths. The setting is a very similar alternate Earth, between the 2000's and 2020's. I'm asking for a way that would still keep at least most of the power-grid working, but that would keep them from turning it back on from the inside. [Answer] # This happens quite frequently with the Internet actually Earlier in 2022 [Tonga and much of the South Pacific went dark](https://www.bbc.com/news/technology-60069066.amp) on the Internet because the undersea fiber cable was damaged by an earthquake. Many Asian countries have gone dark for the same reason, which is why [Jeff Bezos bought his own transoceanic Internet](https://www.datacenterknowledge.com/archives/2016/05/13/amazons-cloud-arm-makes-first-big-submarine-cable-investment) - the Hawaiki Submerged cable - for Amazon. Elon Musk wants to solve this problem with Starlink replacing undersea cables with satellites, and it will be much harder to black out a whole country, but it won’t carry the speeds of a fiber cable. The answer is, yes you can black out a small country from the Internet. However, countries can form their own internets (with a lower case ‘i’) which will be very difficult to shut down. The proper noun Internet refers to the network across the entire globe, and there is only one of them. That is why it is a proper noun. Any country, organization or company can build their own internet and protect it, like China does. Those internets do not necessarily have full access to the Internet (such as global Domain Name Service or ARP resolution). Since the question says “internet” rather than “Internet,” this needed to be pointed out. [Answer] In the short term, yes, this is perfectly possible. Especially if country 1 houses the backbone nodes that supply internet to country 2, although that's just convenience rather than a hard requirement. In September 2021, New Zealand suffered wide-spread internet outages when someone launched a DDoS attack against an individual... although the outage itself may in fact have been because of the response from an internet provider. This is far from the first time this has happened, and the results have been significantly worse in some cases. I recall a couple of decades ago when NZ's internet went out for 3 days because a massive DDoS attack cooked several backbone routers in Australia. Some terrible decisions by the backbone providers had left the country without adequate backup links, and only those with dedicated satellite links were able to communicate outside NZ the entire time. Similar things have happened in other countries. In 2011 a 75 year old lady in Georgia (the European country, not the US state) was digging for scrap copper and damaged a fibre cable. Sadly for Armenia, this cable was the single point of communication with the outside internet. The entire country, and half of Georgia, was offline for more than 5 hours while repair crews worked on fixing the cut section of cable. So yeah, you can take countries down fairly easily if they don't have adequate fallbacks. If you control the territory where all of their internet links are then you can 'accidentally' cut a few key cables and they'll be offline until either you fix the cables again or they manage to get internet through some other territory. And even if you don't have direct access to those cables you can do a lot of damage with targetted DDoS attacks. > > Country 1 could have the help of other governments too, and would choose this as an alternative of prolonging the war and causing more deaths. > > > Depending on the size of the country and the complexity of internet use you could be causing more deaths if the outage lasts for more than a few days. Pretty much everything we do these days relies on the internet. Take away access to the internet and within a few days everything goes to hell. Supply chains break down without access to their cloud-based systems. Banking systems rely so heavily on internet access that all of your POS systems go offline immediately, making it impossible to purchase anything with your cards. People get desperate and start doing stupid things like looting local stores for food. Hospitals can't access medical records. Civil unrest is already high because of the spit, so next thing you know you have riots, looting, destruction, cats and dogs living together in harmony... you know, all the chaos. But you'd never actually do that, right? After all, internet access is a fundamental human right these days. You'd have to be some kind of monster. [Answer] I am not an IT expert but it appears feasible to cut off most of 'the internet' from a small country or part of a small country in many situations. Firstly, for a small nation, most internet sites are based in other larger countries and many smaller countries only have a limited number of connections to the rest of the world. For example, New Zealand only has four submarine cables connecting it to the rest of the world. If these are cut or if the junction points are controllable by country 1 then country 2 will lose access to all major international web sites sites including commercial (Google, Amazon, Alibaba), financial (international banks and stock exchanges), communication (overseas e-mail, zoom etc), social (facebook, twitter, tinder, etc), media (netflix, neon...). A larger small country may have some mirror sites for some of these organisations, but it will rapidly get out of date. Even in a nation with numerous links to the www, local regions of the country may only have a few vulnerable connections. Once again, taking NZ as an example, I believe the South Island has only one cable from the North Island which provides all its international traffic. Secondly, when you type in a web address or an e-mail address (worldbuilding.stackexchange.com for example), your local server needs to know what IP address (the 123.456.321.654 thingy) to go to for a connection. This relies on DNS root servers which act like giant centralized phone books. Your local internet service provider may cache some of these addresses but certainly not all of them. So if the country's local DNS servers are in the control of country 1, it may be impossible for a computer in country 2 to find where to connect to another site that is also in country 2. Now country 2 may be able to solve some these problems - eventually. If they have some satellite connections then they could transfer communications to external servers via them - but in the short term this is likely to be expensive and provode only a very limited data service. If they have borders with sympathetic nations new land links could be added or upgraded or loaded up with more traffic. Even in the short term it woul dbe unlikely that country 1 could put country 2 in a total internet blackout forever, but there would likely be significant disruption for an extended period. [Answer] "It depends". Internet connectivity requires, at some point, bits to flow between your country and another. At the other country's end of the flow of bits is some equipment, owned by a company or government. If they turn it off, no more bits flow. Depending on how many links lead from your country, and how many neighbours you have (and how likely the neighbours are to co-operate with each other against you), the ability to turn off all of these links may be trivial or it could be as hard as getting the whole of the UN to agree on something. Note also that completely shutting it off may be entirely impractical, depending on the tech-level of your setting. [Satellite internet](https://en.wikipedia.org/wiki/Satellite_Internet_access) is expensive and sometimes awkward, but we've had [Iridium](https://en.wikipedia.org/wiki/Iridium_satellite_constellation) for over 20 years, [BGAN](https://en.wikipedia.org/wiki/Broadband_Global_Area_Network) for 10 years, Starlink for 2 years, and there's been plenty of stuff even prior to that. Preventing all kinds of satellite access is probably impractical without doing some kind of active jamming, and that might require flying ECM aircraft through hostile airspace, and is therefore not the sort of thing you'd do unless you were at war with someone. Disconnecting the regular kind of internet would certainly cut off the vast majority of the civilian populace. (and thinking about it, if you live on the border or on a suitably tall hill, and possibly have a decent external antenna, you may be able to get normal cell connectivity to neighbouring countries, who are less likely to cut off internet access to their own population. it'd be easier to do what you want if your story was set 20+ years ago.) ]
[Question] [ I have a mosquito in my story who is suspended in amber. The chunk of amber it is encased in eventually finds itself drifting through deep space without any sort of human-sourced protection (long story). After millions of years, aliens find the mosquito in its chunk of amber and remove it, finding that the mosquito’s biology is intact (though it’s definitely dead). Could the mosquito “survive” for this long? The biggest problem I see is temperature- even if very low temperatures don’t damage the mosquito, the heat of any nearby sun might melt the amber (and the bug). [Answer] Ionizing radiations and energetic particles will surely cause a cumulative damage to the tissues of the mosquito, unless the amber has some serious thickness to act as a shield. Don't forget that one of the main concern for space travel is caused exactly by the lack of shielding provided by Earth atmosphere and magnetic field. Same would happen here. [Answer] As other answers have pointed out, cosmic radiation will cause considerable damage to the DNA and organic tissues of the mosquito, even when the bug is encased in amber. If you want the aliens to learn about biology from the mosquito's remains, you are going to need more radiation shielding! The abstract of this 2016 paper (<https://doi.org/10.1016/j.asr.2016.12.028>) indicates that clay from asteroids could be mined and used to provide enough shielding from cosmic rays to keep astronauts safe while in space. Thus, if you amber was buried underground and somehow catapulted into space (Panspermia anyone?), the amber and mosquito would be protected from cosmic radiation by a mass of stone and clay. Putting the amber in an asteroid also gives your aliens a reason to find the mosquito to begin with. An alien miner can discover the amber deposit when processing the asteroid. [Answer] > > Could the mosquito “survive” for this long? > > > No. And you don't even need space to destroy your mosquito or your amber. It's not even possible on earth. When you open up amber that is millions of years old and has insects encased in them, all you'll find left of the insect is some black dust. (Source: A professor of palaeontology in [this Dutch news article](https://nos.nl/artikel/2431505-jurassic-world-beetje-in-het-echt-kip-met-dino-eigenschappen-in-de-maak)). If there's going to be any amber left after drifting through space for so long, your mosquito is going to be nothing but black dust. Certainly nothing with anything that would be recognizable as 'intact biology'. [Answer] The amber will slowly sublime in space. When it's gone, the mosquito will follow. I don't know how to calculate how long this will take, but "millions of years" aren't going to leave much. [Answer] Short Answer: The radiation and heat would cause tissue damage and melt the amber. Long Answer: So to calculate the change in temperature we need the formula of, H = Cp × M × ΔT. ΔT is what we are looking for. The sun outputs 1370 watts of energy to the start of the earth's atmosphere. We'll look at how hot it will be 100 seconds after it starts its trip. Therefore the amount of Joules it will be receiving are 137000 J. I couldn't find info on the heat capacity of amber, so I'll just use the 840 J/kg∙°C of glass. I am assuming the mass to be around 50 grams. Plugging these number in we get a change in temperature of about 3262 °C. The melting point of amber is 395 °C on the higher end. In conclusion, the amber would melt, and I am not doing equations on the radiation but if it's a problem for humans, I am pretty sure mosquitoes won't enjoy it either. ]
[Question] [ In fantasy and science fiction cool monsters and creature desgins constantly appear, this feature specifically (a mouth that exists in and occupies a good portion of the ribcage area) doesn't seem to stick to what is biologically or physically possible, but sometimes their body shapes could work or at the least look similar in the real life. So in this case I have the doubt about if its possible that some creture could have an open rib cage as it's mouth or something that could look similiar, this also can be interpreted as a second belly or chest mouth. These are some examples I found to illustrate better what I mean: > > [![Would be so convenient if a creature with this "chest mouth" also looks like a humanoid. https://www.adammiconi.com/product/chest-ripper-poster/](https://i.stack.imgur.com/kM4c8.jpg)](https://i.stack.imgur.com/kM4c8.jpg) > > > > > [![In this case isnt just the opening of the rib cage also unfolds a kind of tentacles](https://i.stack.imgur.com/3UoQd.jpg)](https://i.stack.imgur.com/3UoQd.jpg) > > > [![](https://i.stack.imgur.com/NLQCG.jpg)](https://i.stack.imgur.com/NLQCG.jpg) [![https://www.deviantart.com/zanten/art/Nagah-Serpentes-anatomy-1-183339660](https://i.stack.imgur.com/YcpWX.png)](https://i.stack.imgur.com/YcpWX.png) [![This looks more like a desgined "biomechanical" creature but still being a good example. https://demitsorou.tumblr.com/post/175333692538/monster-girl-suurata-oc-of-themugbearer-shes-an](https://i.stack.imgur.com/IKApo.png)](https://i.stack.imgur.com/IKApo.png) > > [![Here something different instead of a continous open mouth are two mouths.](https://i.stack.imgur.com/vRqec.png)](https://i.stack.imgur.com/vRqec.png) > > > Lastely I saw questions about the possibility of the existance of fantasy like creatures and for me this chest mouth is a very interesting concept i'd like to use, but I dont know about the great changes to the anatomy and organs to make it possible. Summing up: Is it possible for a vertebrate animal, given our understanding of biology, to have a mouth located in it's chest in a ribcage-like fashon? If so, what changes to it's overall anatomy would be needed in order for this trait to exist? (I tried to think how this could affect it and I'm almost sure that a thing like this is not currently possible for the earth animals as we know them, maybe alterating the evolutionary story changing the developing of the notocord, so probably bilaterial current creatures are discarded, but maybe some arthropod with retarded mandibules and a lobuled head, but this is very different from the initial idea. So my best current guess is a radial organism like an equinoderm with a centered body mouth but are not vertebrate like creatures). [Answer] Reality Check: PASS! The physiological arrangement you're asking about is within the range of the possible, though, at least for strictly Earth creatures, not within the realm of the probable. We will have to consider some changes to the basic Earth mammal body plan for this to work. Here's what a human looks like inside without her arms, shoulders, and associated musculature: [![enter image description here](https://i.stack.imgur.com/P2jjN.png)](https://i.stack.imgur.com/P2jjN.png) The whitish blob in the middle is the heart all tucked inside its pericardium. Off to either side, our happy medical students are retracting the pleura, the whitish sacs that contain the lungs. You can see the great vessels on top of the heart, and the bronchus that joins the lungs to the outside world. Lurking behind all that is the shy and retiring esophagus. Now, for the purposes of your creature, you don't really want all these bits cascading onto the sidewalk every time it opens its toothy maw to slaver all over its next victim, right, so all these organs will have to go somewhere else. As per that snaky creature in the illustration in your query, the heart and lungs can happily reside down below. Lungs being what they are, the creature will have to have some alternate means of respiration: perhaps a muscular sac that can, bellowswise, squeeze out stale air and replenish with fresh. But back to the chest! So, here's what a human looks like with the ribs and breastbone in place: [![enter image description here](https://i.stack.imgur.com/2zBMN.jpg)](https://i.stack.imgur.com/2zBMN.jpg) Kind of inconvenient for your creature, that pesky breastbone! So what we'll do is split it down the middle, and use the bone to secure some [nasty, big, pointy teeth](https://www.youtube.com/watch?v=kkh-IGmMUwU). Like the girlbeast you referenced, we can also have an outer array of teeth attached to individual bones whose musculature allows some freedom of movement. The main action of the maw will be accomplished by powerful muscles that attach to the ribs along the spine: these will open and close the mouth very nicely. Lastly, the ribs will be entirely of bone, without any appreciable cartilage. There are not a lot of good anatomical studies of such creatures. Here's a reasonable one: [![enter image description here](https://i.stack.imgur.com/tmPhY.jpg)](https://i.stack.imgur.com/tmPhY.jpg) Pretty much building up on the ribs and halved sternum we'll have some standard oral mucosa (lips, gum tissues, with optional tongue). Pretty much the entire thoracic cavity will be now be one gigantic maw, all pink and slobbery. The illustration shows a standard uvula at the back of the oral cavity -- but I don't think that makes much anatomical sense. Basically, the entire inner surface will be gum tissue surrounding bony plates with structures a lot like the palatine rugae: [![enter image description here](https://i.stack.imgur.com/5kPjv.jpg)](https://i.stack.imgur.com/5kPjv.jpg) While the terrifying fangs look horrible as they're rending flesh, it's going to be the job of the inner bits to crunch and crush to a frothy pulp. Possibly the inner teeth will be like the [oral plates of a ray](https://www.wikiwand.com/en/Cownose_ray). Basically, if you're lucky enough to get past the outer layers of fangs, once you're crushed a bit, it'll just be a short trip through the gullet and down into the stomach! [Answer] Crabs don't have necks... depending on the species, when they stand up, the mouth seems to be in the middle of the "chest". Crabs have evolved from creatures similar to lobsters, but somewhere along the way they lost their tail. In the same process their abdomen took its current shape. An alien creature that undergoes the same process and then becomes more humanoid (including developing vertebrae, to sustain a humanoid stance and gait) might have a mouth where the chest is. --- I also like to believe that vertebrates ultimately come from roundworms. AFAIK all roundworms have mouths at the front end of their bodies. Some flat worms, however, have their mouth right at the middle of the body - should vertebrates have evolved from them, they might have mouths at the "chest". [Answer] What is the point of a big mouth, if you have no place to put the food? There is a reason why animal mouths are all in proportion to their bodies.If you want a really big mouth, you have to create a really huge body, that can contain a digestive system proportionate to the mouth. Your next problem, is how to get food to the mouth. Mammals have the mouth on their head for a reason, because they can move the head around to where the food is. As an alternative to moving the mouth, you would need prehensile mechanisms that are able to bring the food to the mouth. A mouth on the chest does not offer much mobility. In which case, a mouth with sharp gasping teeth would have no benefit. The prehensile mechanisms have already captured and grasped the food. Now, you need to consider the pre-digestive function of the esophagus. The stomach is where it is for a reason - the food goes through a pre-processing stage as it goes down the esophsgus. It also acts as a valve, preventing the contents of the stomach from regurgitating. Even snakes have a lengthy esophagus. So your creature would need a way to keep the food in the stomach, a clear division and buffer between the mouth and the stomach. So where are we? A large animal with enough limbs to have at least a pair free for food aquisition, and considerable room between the mouth and the stomach. Something with a very stretched torso, perhaps, or a horse-like creature with two extra limbs, a centaur, with the mouth in the lower chest between the shoulders, still allowing for an esophagus, and perhaps allowing the creature to kneel down on its front legs and eat from something on the ground. [Answer] *Mimetics and Extreme Body Mods:* I think it's unlikely for a giant mouth in the chest to naturally develop in a mammal. That being said, I can think of a couple of ways the APPEARANCE of a human with a giant mouth in the chest could evolve. First, why a giant mouth in the chest? Mechanically, it doesn't make a lot of sense. The best logic I can think of is that the species doesn't chew food so much as "swallow" big food items and carry them around until they can conveniently digest them (possibly externally). A big mouth parallel to the stomach doesn't provide a good digestive system. Maybe they start the digestion this way, then regurgitate the food in a sort-of composter, applying additional enzymes as needed. So now we need to consider why and how of this. I would suggest this organism is an ambush predator amidst hostile humanoids. The body looks human, because the prey is human. A "thin" predator murders someone, hastily stuffing the body (or at least the organs, the best part) into their stomach to carry away in secret. Then the "Fat" predator removes itself from the murder scene with the food (not even chewed, just gulped). The appearance of being human is camouflage. They mimic humans to close to killing range. They could easily be intelligent, if desired, but regardless would need to be clever. Children, being small, would be ideal prey (thus the appearance of an innocent girl, but a seductive/maternal female would also be a good choice of shape for foolish males). Any number of species could evolve closely with humans and mimic their shape to prey on us. The head might not be a head; it could be a modified limb used for grabbing (that may thus hinge open way further than a natural mouth would. I imagine a large claw/pincer resembling a head). A lizard might have an enormous head taking up most of it's "body," with the "head" being a decorative part or a grasping limb. Several of you images look like arthropods, which have an extremely diverse set of body shapes. In a previous question, I suggested an octopus could [mimic skeletons](https://worldbuilding.stackexchange.com/questions/188632/anatomically-correct-sentient-skeletons/188640#188640), and the visuals on some of your images are very octupoid. The "mouth" could actually be a ring of tentacles resembling a mouth, but the actual mouth might be tiny in comparison. The teeth might even be tiny arms or tentacles to grasp food or guide it to the actual (small) mouth. Another possibility is this organism is like a slime mold, able to readily change its shape. The "mouth" would really be the organism shaping around someone, since it doesn't really have its own distinct shape. It would kill someone, then engulf them, then (if it can somehow move this way) "walk" the engulfed body off to somewhere the whole thing can hide and gradually digest its prey. For a ghoulish variant on this, some [wasps are able to pith cockroaches](https://www.scientificamerican.com/article/how-a-wasp-turns-cockroaches-into-zombies1/) and make them follow mechanical commands. Imagine doing this to a person who then could be forced to walk to their doom, possibly even dig their own grave, then climb in and bury themselves. * As one additional possibility, I would suggest this could be a form of very extreme body modification. People have suffered injuries where their [stomach is open to the outside](https://en.wikipedia.org/wiki/Alexis_St._Martin), and even lived that way for years. A person into extreme body mods could have their stomach altered to be open, and their skin modded to look like a huge open maw. Implants would resemble teeth. This wouldn't be functional, but people are crazy/sick/experimental and such an appearance could be possible with enough medical science. ]
[Question] [ I am writing a story, in which a mad scientist (based on Ted Kaczynski) wants to kill as many people as possible with an artificially created disease. The idea is, that more complex societies are better able to solve many small problems (wildfire, etc.) compared to hunter-gatherer societies, because of the possibility of resource distribution. However, complex societies are affected more strongly by big problems, because so many systems are interdependent. So, if enough people in food production, energy production etc. die, then everything collapses. People today are very dependent on Walmart etc, and if the food distribution failed, we could not just quickly go back to local farming. So my question is: What kind of disease would such a villain use? I picked a bacterium, because it seem to me bacteria are more malleable with genetic engineering. Is that true? How do different factors, like incubation time, the method with which it spreads, and deadliness, affect total kill count? Many of the deadliest diseases like the plague occurred before we had access to antibiotics. Does that change anything, and if it does, would it be realistic for a biology professor to have access to the held back antibiotics to make the bacteria immune? Instead of killing people directly, would the "stealthy" approach of making people infertile, similar to mosquito killing gene drives, work? Would it be enough to make a portion of the public infertile, or would humanity just evolve resistance to the virus? [Answer] I'm not an epidemiologist, but I do a lot of computer science and at a high level, infection in computer networks and in humans have a lot in common. Ultimately both come down to two factors - transmissability and payload. Let's discuss transmissability first. In epidemiology, there is a factor called [R0, or R-nought](https://www.vice.com/en_us/article/pgazpv/meet-r-nought-the-magic-number-that-spreads-infectious-diseases). This was made famous in the movie Contagion, but if you check the link you get a more realistic definition of the term. Ultimately though, the higher the R value, the more infectious it is and therefore the harder it is to control. Ebola for example has an R value of around 2. Measles, depending on where you are, has an R value between 12 and up to 20. In most of history, the really deadly diseases have not been as infectious as the ones that cause less severe symptoms. When that balance is breached, we have major 'plagues' that wipe out a lot of people and make the pages of history. This comes down to the payload. Whether it is a bacterial infection or a viral, or even fungal, if it spreads easily and has hard to treat and severe symptoms, you'll have trouble with it. Personally, I'd go with fungal. Mushrooms and their poor cousins are scarier than you might think and these days we have antibiotics to treat most bacterial infections (although some are becoming highly resistant to our antibiotics, just look up MRSA) and we are also making good headway with anti-virals at the moment, but I haven't read a lot on good anti-fungals of late. These things can be lethal - just look at the [death cap](https://slate.com/technology/2014/02/most-dangerous-mushroom-death-cap-is-spreading-but-poisoning-can-be-treated.html) mushroom and of course the creepy [Cordyceps](https://www.theatlantic.com/science/archive/2017/11/how-the-zombie-fungus-takes-over-ants-bodies-to-control-their-minds/545864/) mushroom. The point being, that if you can get fungal spores to reach a high value through sneezing or some other form of spread by infected people and animals, then humans currently don't have a lot of defence against them, and we already know that they are capable of killing us. So; ultimately you need to design a disease that is really infectious and hard to treat while also being fatal, preferably over a long enough period that the person can infect others, but not so long that we have time to treat them. Ideally, like many versions of the common cold, they'd remain asymptomatic (not showing any signs of having the disease) for several weeks while still being contagious, so that they are infecting many others before they manifest the symptoms that lead to them being quarantined. A final word on antibiotics and the idea of the 'right' ones being held back by the designer of a disease - you don't have to do that. There are already some bacteria that are becoming resistant to the antibiotics we currently have, and ultimately we are in a constant arms race with bacteria, finding more effective antibiotics to kill them while they adapt to our treatments. In point of fact, our use of antibiotics is accelerating the evolution of these bacteria, only allowing the most resistant of them to survive our treatments. So, even if you are looking at a bacterium for your disease, you don't need to 'withhold' a specific antibiotic, you just need to release a disease that has become resistant to the current wave of antibiotics. It's going to take time to counteract it and by that time, you've already killed off a lot of people. [Answer] one way is to have a bunch of bacteria and give it all the antibiotics slowly but surely, before releasing it. it is an actual problem of today where bacteria are adapting to the current antibiotics and are getting stronger, forcing us to make new better antibiotics. i know a lady who everytime she got sick, or got hurt she would take an antibiotic i think was called penticilin, and then when she got really sick and really needed to go to the doctors they realized she was taking too much and that the bacteria have evolved to get past it. so they had to kill the bacteria in her with a way stronger drug before anything bad happened, and had to give her a lesson on how they worked. so i would assume that using a lot of antibiotics to the point where a bacteria that is harmful to humans is practically unkillable, would be a neat way to give a narrative on todays medical field, and would be a cool plot thing. [Answer] The disease is an infectious meme. <https://en.wikipedia.org/wiki/Meme> > > A meme is an idea, behavior, or style that spreads from person to > person within a culture—often with the aim of conveying a particular > phenomenon, theme, or meaning represented by the meme. A meme acts as > a unit for carrying cultural ideas, symbols, or practices, that can be > transmitted from one mind to another through writing, speech, > gestures, rituals, or other imitable phenomena with a mimicked theme. > > > The meme is transmitted rapidly and freely, mutating into many related memes as it goes. Large segments of the population do not realize the meme is a disease and so readily receive and propagate the infection. The meme strikes at the heart of what you recognize is the hallmark of advanced societies: the interdependence of systems and people. > > The idea is, that more complex societies are better able to solve many > small problems (wildfire etc) compared to hunter gatherer societies, > because of the possibility of resource distribution, but are effected > more strongly by big problems, because so many systems are > interdependent. > > > The infectious meme is that elements of society are not pulling their weight in the system, or are evil and should not be included in the cooperative society, or should be contained, or should be destroyed. Almost half of the society is in the targeted group. Infectious ideas have been responsible for several genocides. Such ideas are dangerous because like a disease where the immune system attacks the organism, ideas like this harness the problem solving power of the complex society to solve the problem of the undesirable population within it. [Answer] I think a virus is better, because a bacteria can be easily killed by antibiotics. Bacteria, can become antibiotic resistant, but you need to consider that there are hundreds of antibiotics and new one can still be developed. Create a cure for a virus is much harder. [Synthetic\_virology][1] <https://en.wikipedia.org/wiki/Synthetic_virology> is possible even if it is still a branch of research. The best virus to kill most people is a virus that spread himself very fast, it should spread through air and start infection of respiratory organs. As flu or cold, this kind of virus can easily infect most people of the world. But to be perfect, the virus should be also highly mutable and hide himself from immunitary system, at the start of the infection it should cause very slow sympthoms to avoid to alarm people. As example you can take HIV, because it hides very well in the host victim, and make it spread like cold. Then you just need to add a last stage, the virus after several months/years of incubation develops a hemorrhagic fever like ebola that will kill most of the population. ]
[Question] [ In one of my stories, I have a race that communicates using only two sounds: "O" and "U". This can be strung together like this: ``` Uuuoouoouooouuuooouuoouoououooououo ``` Or something like that. There are no pauses between words within a sentence. It is essentially a binary language, just like what machines use. ## Using only two phonemes, how complex can communication be? The following concerns come to mind: 1. How can each word be differentiated without any pauses between words? 2. Assuming you can get past the above problem, will it simply take too long for them to convey information? [Answer] This is fairly easy. With tri-state it's even easier, but for now let's consider just using a click or silence (a la pure binary: 00101010). The answer is a lot and as quick as their memory can handle. Let's lay some ground theory: * There are a small set of "proto verbs" (Incorrect terminology so I'm having trouble sourcing this), of quantity less than 30, some of which have no existing counterpart in English. Nevertheless, you can define all verbs using that small set in the right combinations with other words. * Similarly, you can do the same with many parts of speech (Cat: four-legged furry mammal...etc.) * Nouns/Adjectives are your largest collection. Although you can do either-or. [StackExchange](https://english.stackexchange.com/questions/55486/what-are-the-percentages-of-the-parts-of-speech-in-english) would put this at somewhere between 19% and 33% utilization, I believe. Looking at [English Dictionaries](https://en.wikipedia.org/wiki/List_of_dictionaries_by_number_of_words) for a maximum for a number of words puts us at 155 thousand nouns/adjectives which can be enumerated with 18 bits. * If the universe has roughly 1082 atoms in it then you can enumerate them with 272 bits which will be of such magnitude that it would be laughable to consider filling it completely. You can use that number as a max. I prefer 64 bits. Your minimum enumeration to match English is less than 18 bits using proto-words (probably something like 12 bits), and 19 bits to match exactly. * Words consist of definitions, which are combinations of either other words or proto words. It is compression. Each word added adds to the memory requirements, and the bits needed to enumerate all words. But, adding words increases transmission speed. You can trade memory for speed almost as much as you want here. * *Crucially* you can even compress those words by frequency of usage simply by adopting the same trick that saved Unicode.... [UTF-8](https://en.wikipedia.org/wiki/UTF-8), just pick a "byte" size that encompasses enough of your common words and make the rest extended bytes. Other variable-length encodings are usable as well. What you end up with is as much content, almost as fast as you please (within a log-factor), as specific as you want (this atom), tailored to your language/culture. What's the downside? The number of sounds is a multiplier on transmission speed. Any crafted language could do the above-described things. But the more sounds you have the quicker you can do so. 26 sounds? 4 times the content in two sounds (log(26)/log(2)). But as far as "as quick as their memory can handle" [there's a limit: ~380 wpm](https://www.youtube.com/watch?v=zUDqI9PJpc8)... which probably is present for non-humans but just different rates. What about adding silence? Tri-state let's you scrap the UTF-8 "extension bits", or gives you another symbol to play with (log(26)/log(3) now). Speed or compression gains either way. [Answer] > > It is essentially a binary language, just like what machines use. > > > Unless they never stop vocalising, it isn't really binary as you have O, U and silence. Binary signals just have high and low, or on and off. [Tri-state](https://en.wikipedia.org/wiki/Three-state_logic) stuff is distinguished from plain old binary. > > How can each word be differentiated without any pauses between words? > > > So, study of spoken language isn't my forte, but I note that many foreign languages that I do not understand do not have word-boundaries that I can recognise... they just seem like more-or-less seamless flows of sound, broken up into sentences. I can understand the word boundaries in languages I'm more familiar with, because I recognise individual word-sounds and my brain does the parsing for me. Youmightconsidertextwithoutspacingtobeasimilareffectwhereyoucantellthewordboundariesbecauseyouarefamiliarwiththeactualwordsthemselves. If you really wanted, you could consider having a special sequence to defined End-Of-Word, but that just seems unnecessary and would take up valuable conversation time. You'd probably still want to pause for end-of-sentence though. > > Assuming you can get past the above problem, will it simply take too long for them to convey information? > > > Depends how fast they can modulate their voices, doesn't it? For a technological example, consider [radioteletype](https://en.wikipedia.org/wiki/Radioteletype), aka RTTY ([sound sample](https://www.youtube.com/watch?v=wzkAeopX7P0), youtube link) which can give you 60 words per minute, which is less than half the rate of spoken english (faster rates do exist, but they're not reall meat-emulateable). This is done by sending one character at a time, 5 bits per character. The efficiency at which you can send information depends on how you've put together your lexicon. Morse operators used many [specialist abbreviations](https://en.wikipedia.org/wiki/Q_code) for important common words, questions and answers. Your language probably needs the same. Uncommon words might take much longer to say, which means that unless the race is quite patient they might have issues communicating complex or technological concepts. For non-technological examples, consider birdsong. I'm having trouble with the precise search terms that will be of most use to you, but trilled portions of birdsong can go as high as 30 distinct pulses per second (1800 bits per minute, 6 times faster than the basic RTTY mode). That needs some fairly sophisticated muscles and brains to do that trick, though. [Answer] Latin written with [scripta continua](https://en.wikipedia.org/wiki/Scriptio_continua) had words without spaces. I have observed that some modern Italian speakers also string their words together without spaces except when they need to breathe. The key I think it to recognize words as such as soon as they are spoken and mentally file each one as you hear it and get ready for the next. The other thing about people is that there are many ways to inflect the sounds O and U. Extra or different emphasis can denote the start or end of the word: for example U U U U U U is not the same as U U U U U U. You can tell I am emphasizing my U because it is louder, and also my eyes bug out slightly and I spit. [Answer] ### It could function, but how would it evolve? A two-sound language is basically binary and is perfectly capable of transmitting arbitrary amounts of information. However, unless the species was constructed artificially or they voluntarily adopted this system after evolving a culture, it seems unlikely that such a species would ever evolve the ability to talk in the first place. Human language evolved from simpler sounds, each conveying a unique concept, long before we began stringing them together into words and sentences. While the exact sounds early humans used are unknown, we can make guesses; suppose that humming was a sound made while pleased or satisfied, hissing when angry or in pain, a grunt when ready to travel, etc. This could serve as a proto-language where the species was already accustomed to communicating intent through sound, which could lead to using these sounds to convey greater meaning through analogy, like using "ma" (a sound conveying comfort) for mother or water. A single syllable in a binary language, however, conveys too little information to be useful before you start stringing sounds together. Because of this, it seems very unlikely that a species capable of producing only two sounds would even think of using sound as a means of conveying information. It is more likely that they would develop a language based on non-verbal communication. Moreover, it is very inflexible - if I replace a B with a P in a sentence, 90% of the time you will understand what I mean - but if I replace a zero with a one in a binary language, you will hear a completely different word. A language this precise would be very difficult for living organisms to use and would have a hard time evolving from simpler forms. [Answer] So far no one has mentioned a modulated stream. Consider having two states - off and on. Perhaps the off state is "o" and the on state is "u". You can change the length and or volume of the on state and get just about any sound that you want with the caveat that you will hear an overtone squall. In fact the way humans speak is that we produce a carrier tone, rather several tones overlaid, then modulate that sound to produce "o" and "u" among other sounds, essentially shifting the phase of the overtones. Consider back before computers had sound cards, software authors developed methods for playing polyphonic sound over the binary PC speaker, called [pulse-width modulation](https://en.wikipedia.org/wiki/PC_speaker#Pulse-width_modulation). The PC speaker is an internal, simple 5 volt speaker which typically comes with the computer case, and whose hardware only provides an off or on state, i.e. switching that voltage on or off. Tones can be produced by utilizing separate timer hardware ( standard on most computers and separate from the CPU ) for generating an audio-range system timer. That timer signal can then be used by software to turn the power to the speaker off and on at regular intervals. By determining how many intervals to skip between switching the speaker from an on to an off state, this configuration can be used to approximate polyphonic wave forms on an extraordinarily simple device. Doing this essentially pulses the voltage through the speaker, and because of the mechanical nature of it, the modulated signal actually places the speaker cone in the approximate position it would be in if it were playing a smoothed waveform, with the exception that the carefully spaced pulses of current causes the speaker cone to jolt from one position to another, which has the affect of overlaying the wave with the carrier tone. Also this configuration can only play sound up to half the frequency of the available timer. In the case of the timers available to use with the PC speaker, the max available was either 18kHz or 10kHz, causing a buzzing overtone of about 9kHz or 5kHz respectively. You can hear an example of the PC speaker thing [here](https://www.youtube.com/watch?v=atw10SeuCos). It's messy, and it's much easier to hear in person, but it's easily possible to make out any complex sound. Not sure how this would sound starting with "o" and "u", but I imagine it wouldn't be much different, just that the overtone would have a quality that is perhaps more voice-y and less like the "8-bit sound" of a PC speaker. [Answer] Chinese and Japanese (and other such a languages) have an interesting pronunciation structure: each syllable has a certain "timeframe" and those syllables are pronounced in a rhythm. There are "long" ("two-frame") syllables and "short" ("half-frame") ones, but the timing of "frame" should be kept. These languages have tens of syllables. But the proposed language would have 10. 4 "basic": OO,OU,UO,UU; 4 corresponding long ("long O"-"long U"); and 2 "short" ones: O, U. That would be enough for a language, but on average words would be 2-3 times longer than in Chinese and Japanese. This is not a problem though, since some existing primitive languages have some very long words (mostly because they have too few "basic words", and they call a boat "hollow-trunk-that-goes-over-water") and it has worked for them. [Answer] Very feasible indead. But the written language needn't be binary. Indeed the letter B could stand for the sequence of sounds uuuouu. (I assume you are including spaces, or pauses? Or you could have s space be a special sequence say ououououououo. ) If the sounds are continuous with no spaces you might need a special sequence to indicate the start of a sentence e.g. ouuuuuuuuuuo The might be some ambiguity but in context the language could make sense. [Answer] Take a look a Huffman encoding ([wikipedia link](https://en.wikipedia.org/wiki/Huffman_coding))-- it's a form of compression that uses shorter binary sequences for more common symbols. Also consider that all humans have huge brain structures just for our language. I can't see this limitation being a huge problem. [Answer] Other have covered the binary issue pretty well. Remember though that vocal communication, as in humans, is supplemented by many other forms: while the old line about only 20% of communication being verbal is a misunderstanding, the aliens may have even more developed use of gesture, tone, expression etc. (Or semaphore: "Cathy!!") And if their vocal language does limit them, they may be smart enough to develop a sophisticated written language to transmit data faster. As with humans, reading may be much quicker than listening; with them, writing (or texting, if they have the tech) my be quicker than speaking. What looks like a limitation may mean they end up communicating better. ]
[Question] [ [![enter image description here](https://i.stack.imgur.com/VGehe.jpg)](https://i.stack.imgur.com/VGehe.jpg) In a world where tectonic plates decided this whole continental drift fad was just too much work and lets just hang out for a few more hundred million years, life has arisen, stomped around for a while, sat down for a good think, and decided to work together. An empire is born. This empire has a few things going for it: * They have achieved a technology level equivalent to the Romans at their greatest, with a representational democracy since that whole monarchy thing just got too confusing if you had more than one kid (and what if the brat is an idiot?) * The single religion is highly resistant to fracturing, mostly because anyone who tries to subvert it spontaneously bursts into flames on account of the human body not being a good conductor of lightning bolts. * Due to there being only one land mass the amount of racial drift is very minor. in addition an ancient custom of marrying outside of the tribe in order to avoid interbreeding has carried over, so that looking for mates from afar (or who had recent ancestors from afar) is very common. Thanks for the idea nzaman. All this adds up to a civilization that is fairly resistant to fracturing, though people are still people, so communications are very important. Especially since it is a land mass of around 60 million square miles (155 million square kilometers). Sea travel is possible around the circumference of the super continent, and they have developed sailing. Likewise, like the Romans, their road building skills are really advanced. Assuming a centralized capitol near the equator in the general area of "ARABIA" on the map, what kind of advances to Roman travel technology need to be made to keep the empire stable for a significant amount of time? Edit: Perhaps a better question is, is it possible for an empire like this to be stable for a significant amount of time when the fastest mode of travel is a horse? And if not, what is the least impact improvement that can be made to the tech tree to allow it to work? Edit 2: The Active Deity The deity plays a semi active role, but mainly in how the religion is run. Basically the message is similar to the biblical 10 commandments; don't murder, don't steal, there are no other gods, treat others like you would want to be treated, help those in need, etc, along with a short list of harmful lifestyle choices to avoid for a healthy life and healthy society. Where the lightning comes in is in the area of spiritual leaders. If you are (or act like) a spiritual influencer, then you are taking on responsibility over peoples lives, and your words and actions can actively lead people away from the message. If a spiritual leader tries to use power or influence for corrupt personal purposes then they are in danger. If a normal person has a dream and takes on the role of cult spiritual leader to share their new revelation, they come under this rule. The only place that this applies to politics is if a politician oversteps and tries to impose law in a way that affects spiritual matters, in effect becoming a spiritual influencer. If there is something that the message specifically forbids, and someone proposes a law that makes it mandatory/actively encouraged, then they might start to hear thunder on sunny days. But this is not something that the priests have any influence over. They can't pray and ask that someone be smote. By and large, most of the DON'Ts in the message are things that would be considered illegal in most civilized societies, the DOs are things you should probably be doing anyway, and none of them are actively enforced outside of the priesthood/spiritual leaders. Leaders are held to a higher accountability. There are other places where the deity shows some activity, like by favoring those that are faithful to the message, sort of like a Luck +1. There is no law against spiritual leaders seeking political position, but their spiritual position doesn't give them any extra political authority, except that it enforces moral choices. Map image source: [ENCYCLOPÆDIA BRITANNICA](https://www.britannica.com/place/Pangea), who got it from someone else. [Answer] ## Deserts and high mountains means sailing not roads are main transportation Well, you need to consider a few additional factors. When they hear Pangeea, people tend to think of a lush luscious continent full of forests and fertile plains. In fact, as you can see from the map below, there is a vast and foreboding Central Pangean Mountain Chain that made the Himalayas look like a joke. Moreover, they were set across the equator ripping apart monsoon-like winds, driving vast desert belts to the north and south. This is actually good news for your empire, because it means that, just like the Roman empire (which is famous for Roads but was actually kept alive by grain shipments across the Mediterranean) this will likely be based on shipping around the vast and sheltered Tethys Ocean and the mini-continents that surround it. Again, shipping can carry a larger volume of news, goods and people faster (~130 miles per day according to my [source](http://penelope.uchicago.edu/Thayer/E/Journals/TAPA/82/Speed_under_Sail_of_Ancient_Ships.html)) ![Pangaea](https://i.stack.imgur.com/tVLCw.jpg) From the Capital (let's assume from the map above it would be in Africa, around present day Libya) news could travel from around the Tethys sea in about a month at most. So you'd need some fairly significant improvements in shipping technology compared to the Romans to harden the ships for the larger distances across the more open Tethys sea compared to the Med. [Answer] I'm going to add some rough, back of the envelope calculations to the above answers. Assumptions* wikipedia says that the pony express riders covered 75 miles a day: <https://en.wikipedia.org/wiki/Pony_Express> This stack exchange answer says the Roman Legions marched about 10 miles a day: <https://history.stackexchange.com/questions/8226/how-quickly-could-the-roman-legions-march-how-does-it-compare-to-the-mobile-cav> The earth's circumference is 24,000 miles. Pangea looks like it covers about a hemisphere so 12,000 miles from one end to the other. Assuming a seat of government in the center that leads a couple important metrics. How long does it take a message to get from the outposts to the central government? 6,000 miles / 75 miles a day is 80 days. Right off, this seems like too long to me. News of misbehavior in the provinces won't even be heard off in the capital for over two months. I can imagine several ways to mitigate this problem. You could have semi-autonomous regional seats of power that can respond to most situations without direction from the central government. This requires a culture of loyalty as well as audits and checks on power to prevent rebellion and fragmentation. JBH's idea of moving people around, stationing legions from one region in another seems like a good way to go. There are also technological steps such as optical telegraph or semaphore. <https://en.wikipedia.org/wiki/Semaphore_line> But perhaps the technological step up to electric telegraph isn't such a stretch from Roman level technology. I could imagine it developing before steam engines (if coal isn't as plentiful for example) and gun powder (no external threats so maybe the arms race isn't such a big deal). The other metric is how fast you can move troops and material. 10 miles a day means it takes 18 months to get from the central capital to the most distant provinces. That is way too long for a military response so distributed centers of military power will essential (obviously). But once you have faster communications (ie. telegraph of some kind) it becomes reasonable to have legions stationed at 100 mile intervals, so that everything is a 5 day march from enforcers, and they receive orders via the Imperial Telegraph/Semaphore service. Delegating authority, and layers of administration are going to be massive. Civil service will be a big chunk of GDP. But the unifying forces of shared religion, culture, and trade will be your friends. Sounds like a pretty fun world to build! [Answer] Addition based on comments/edited question Regarding size of a Rome-y empire in travel time: On Roman roads, [a message could go about 80km in a day](https://en.wikipedia.org/wiki/Roman_roads#Post_offices_and_services). Handwaving the actual farthest point, let's say that [Hadrian's Wall](https://en.wikipedia.org/wiki/Hadrian%27s_Wall) represented the farthest distance that the Roman Empire stably expanded from Rome. [Hadrian's Wall](https://www.google.com/search?ei=oj6YWuSUI6u0jwTHxKmQDQ&q=distance%20from%20rome%20to%20hadrian%27s%20wall&oq=rome%20to%20hadriansdistance&gs_l=psy-ab.3.1.0i8i7i10i30k1j0i8i13i30k1.43644.44825.0.47513.8.8.0.0.0.0.120.761.1j6.7.0....0...1c.1.64.psy-ab..1.7.759...0i7i30k1j0i8i7i30k1j0i13k1.0.YjUXuQ-mfiA) is roughly 2400km away from Rome. 2400km/80km = 30, which is very conveniently about a month. So, a rough(and far from conclusive) estimate on the maximum size of a Roman-level empire in days-of-land-travel-from-capital is about 30 days. Anything much larger presumably wouldn't be feasible for a centralized, Rome-esque empire to manage. However, ocean/river travel would definitely help the distance. For example, Rome expanded [as far east as Susa in Iran](https://en.wikipedia.org/wiki/History_of_the_Roman_Empire#98%E2%80%93117:_Trajan), a distance of more than 4000km, though about 2/3rds of the distance can be covered by sailing in the Mediterranean. --- Original answer, regarding improvements needed to allow a Pangaempire As you mentioned, the Romans had a great road system, and even they only got to [about 5 million sq. kilometers](https://en.wikipedia.org/wiki/List_of_largest_empires). This is about 3-4% of the landmass you're talking about covering. You would need significant advances over the Romans in travel, communication, and government organization in order for this super empire(Pangaempire?) to function as a single entity. However, since you wanted a focus on travel: [Trains, planes, and automobiles](https://en.wikipedia.org/wiki/Planes,_Trains_and_Automobiles) would be needed to facilitate travel throughout this empire. Ships would speed up travel between coastal areas, however they generally aren't useful for traveling in the interior of continents(unless there are many large rivers). Rail and [highway systems](https://en.wikipedia.org/wiki/United_States_Numbered_Highway_System) today do a good job of facilitating travel throughout current continents, though infrastructure on this scale is far beyond the ancient Romans. Even if they had modern infrastructure, horses and people can only go so fast. On Roman roads, a horse relay system allowed messages to [be carried only 80km a day](https://en.wikipedia.org/wiki/Roman_roads#Post_offices_and_services), a distance a modern car could go in less than an hour. This is why cars and locomotives would be needed, as they are a vast improvement in speed and efficiency over walking. Planes are even better, plus you wouldn't have to worry about pesky mountain ranges. Regardless of the travel method, [reading a list of large transport projects](https://en.wikipedia.org/wiki/List_of_transport_megaprojects) shows that even modern infrastructure isn't at the scale needed by the Pangaean empire. In short, a Roman Empire-level civilization isn't even close to being able to maintain an empire this large. *Modern civilizations have only recently accomplished a few continent-wide infrastructure projects, and you're essentially looking for such projects on every* continent. [Answer] Edit after considerable changes to the question It can't be done** [Here is a list of our world's largest empires](https://en.wikipedia.org/wiki/List_of_largest_empires). As I mentioned, Britain tops the list, but if you look at the map of their greatest extent, you'll realize that they held only as much of the world as they did because of a MASSIVE difference between their tech level and that of the indigenous peoples. As the difference in tech level began to even out, the colonies and holdings began demanding independence, and England couldn't fight such an extended war. (If you think about it, how loyal is a colony, really? Easy to grab. Very hard to keep.) There isn't a small amount of tech that will make your empire come to be. There isn't any tech that will make your empire come to be. You can't keep the world in the dark. People learn about the technology, and soon thereafter, they have it (the American First Peoples are a very good example — they couldn't manufacture rifles, but it took very little time for them to obtain them). It's only the technological difference, and the fact that it's a considerable difference, that allows you to stay in imperial power at all. So, unless your god decrees it, you're chasing a solution that doesn't exist. It's too much land mass, too many people, too little tech, and people learn too quickly. If your empire successfully gained the entire world, it would be a false claim, as there would be fights, battles, and wars everywhere — and all the while your empire is losing men and materials that are fairly difficult to replace. I regret this response, but people 2,000 years ago were as capable of resisting the technological advance of superior forces just as they are today. There's a reason there's never been a militaristic, political, or economic one-world-order on Earth. Big planet, small controlling faction. --- Original Answer A massive problem is that it's difficult for an empire to grow without the ability to hold regional administrators accountable for their actions. Rome had this problem for a number of reasons including slow transport, slow communication, poor logistics, and (thanks to the Caesars) growing greed for personal power. Consider this map of the Roman Empire at its greatest extent. It covers a pitiful fraction of the land you're proposing. So, your question is, what would have to change to let that empire grow by, what, 200,000%? The closest we've every come (the British Empire) was 22% or so of the planet - and that was with late 1700 early 1800 technology amidst a world that was 1500-1600 technology. As the world acquired the benefits of the empire, their desire to be a part of it waned. *I'm going to assume that I can't suggest new technologies. That I must try to coalesce your empire using only what Rome had at the height of its empire.* * You have a god that appears to be very active. That's your single greatest source of control. However, it gives the priesthood 100% of the power. * A law that states anyone guilty of rebellion against the empire or acting not in the best interest of the empire had better off themselves quick before the jack-booted fanatics show up to publically execute you by means of (fill in the blank) along with every member of your extended family the Empire can possibly find. Your god may not like this law, though. I'm just sayin'. If he's OK with it, he'd be quite an accomodating god. Let's call this the "Liberty Through Loyalty Act" (LiTLA) and pitch it as the necessary consequence of not protecting every liberty enjoyed by the people according to what the Empire thinks they deserve. * Roads... roads, roads, roads, roads, roads. A honking lot of roads and a developed civil service to maintain them and make more. And laws that state that anyone trying to take control of the roads away from the empire would be subject to LiTLA by means of hot coals. * A massive mid-level bureaucracy fanatically loyal to the empire. Not only are these guys processing mountains of paperwork, but they're regularly visiting every city. Violating the sacred trust of the bureaucracy is subject to LiTLA by waterboarding. Like the priesthood (and the IRS) they have a dangerous amount of power.... You never send your administrators to their home provinces. * A massive police/military also fanatically loyal to the empire. You're people need to feel 100% safe when these guys are around, so violoating your oath subjects you to LiTLA by a thousand cuts. These guys also have an enormous amount of power (we're up to three now, your emperor, technically, has none BTW, only what fanatic loyalty gives him). You never post your military in their "home" province. * You need to bring the law, a very consistent law, to every reach of the empire. A citizen in the northern wastes should expect the same legal treatment as a citizen in the southern wastes, meaning a well-trained judiciary (subject to LiTLA by suffocation). * You want trade... every ounce of trade you can get. You want people, and your economy, to be in constant motion. Your biggest problem is the triple whammy of the priesthood, the bureaucracy, and the police/military. My thought about LiTLA was an effort to balance the power between these three groups and keep that control in the hands of the emperors and their councils. Your most massive variable is your world's god. Gods get to do what they want, when they want. There's basically no way to balance the power of the priesthood — and they know it. That means you absolutely must, by Divine Decree, have an emperor lead by Divine Mandate. You have absolutely no choice, or the priesthood will assume control. [Answer] Something like Roman Empire should develop along the coast, just like that empire did. Too far inland, you should need a way to make the transportation cheaper or faster. Then you need to improve the communication, as it was already mentioned. Once your empire riches its maximum size, it has to become self-sufficient. That's the real difficulty. Rome was a very large city and coudn't support itself. Every now and then they would mount expeditions to rob their neighbors. When their neighbors became part of the empire, they would overtax them. Eventually, the empire overextended, there was a lot of Rome to feed and it was very hard to collect from the faraway provinces. Things got sour, then dark. So, I propose the following: 1. Your religion should worship an invisible God who sees everything and his prophet is Batman. 2. Every time an official is proven guilty of corruption he is made an example of. Crucifixion, boiling alive, that sort of thing. So, you need to make a proper justice system. You have to have jury duty, judges should be chosen randomly, most trials should be public, etc. 3. Schooling should be both right and obligation. You should have public universities were the elites should study. The others should still have Sunday schools. The greatness of your corruption free system should be drummed into people's mind from birth. No one should be an emperor if they didn't study at Princeton with Aristoteles. 4. Transportation can be improved by building canals. Slaves from the defeated enemies need to dig them. Who doesn't die, becomes a citizen. 5. Taxation should be fair. So, you need your mathematics to develop a little beyond Roman numerals, so that provinces don't get overtaxed, or undertaxed. If they are overtaxed, they would rebel, if they are undertaxed, Rome starves. You need to develop a Roman IRS. 6. Laws regarding food safety should be developed and strictly enforced. 7. Corn, potatoes would be better in terms of yield than wheat. 8. You need to develop banking, safeguard trade, and make high-yield speculations next to impossible. 9. Your rulers need to be aware of the actual limits of their power over neighbors. That has to be in the military manuals, developed by the strategists of the empire. The rulers have to be able to discern if a province needs to be conquered, pacified, or better left alone. I could go on, but I think the technologies needed to make a lasting empire all belong to the category of population discipline. Law and order, plus organization. And lots of pro-empire propaganda built into the educational system. Those could slowly increase your empire, and could even get it to last for a very long time, until population density increases enough, and novel technologies are invented. But, your Roman Empire would probably never extend much beyond the size of the one in history because of the poor transportation and low population density. When those are solved, other empires would have formed and yours would have to fight them to extend. Even with modern day technology we still can't have a single global state. It might be that our civilization will collapse before that ever happens. [Answer] What your empire needs is bureaucracy. First, travel time matters less than you might think. Britain built its Indian holdings when sending a letter took half a year: <http://www.nytimes.com/books/first/m/marshall-east.html>. As long as your provinces don't need troops from the capital at a moments notice to repel invaders, it's OK. The real issue is the principal agent problem. Basically, how do you make sure the provincial governments do what's best for the Empire, and not what's best for each province or each provincial governor (like form a break-away state). Luckily, we still have those problems, because even if technology means the CEO can look instantly at any part of the company, humanity means they'll still have to delegate. And what we've come up with is bureaucracy. Model your Imperial government after a corporation, or if that feels too modern the British empire. For example, corporations control corruption in multiple ways: 1. Clear standards of acceptable conduct (HR deparment) 2. Promotions confer status and wealth, and corruption will hurt your units profits and thus your chances 3. People are incentived to report each other, rather than to stay loyal to their immediate superiors (for example, encouraging rotation through departments, or reshuffling teams periodically) [Answer] If the empire is on the coast of Arabia, the ocean currents run north and south from there, making travel from the capital easy. that means that response times to trouble will be faster than trouble coming to the capital. However, the biggest effect for keeping the empire together would not be in modes of travel or communication. It would be in the terrain. If different areas of the empire are cut off from each other by largely impassible terrain (jungles, deserts, huge rivers, and mountains) then the empire can stay together. The empire is not threatened by a region rebelling. The empire is threatened by a rebellion that spreads. The empire has the manpower to easily put down one region's rebellion. It would not be so easy if the empire had to spread it's forces over several regions. Having to have the ability to suppress multiple regions simultaneously would increase the necessary size of their standing army. Increasing the size of the army would increase unrest since the money to pay for the army has to come from somewhere (usually from the outlying regions). This is one of the things that killed the historic Roman Empire. If your empire somehow survived the process of getting big enough to dominate the entire continent (that's the biggest trick to explain) then, with no external threats, the army size can be much smaller. In fact, with no external threats, the regions would have no legitimate reason to have standing armies of their own. So they would have no power. In that case, if there was to be a threat to the empire, it would have to come from the capital itself. [Answer] Faster communication. Whether it is optical telegraph (<https://en.wikipedia.org/wiki/Semaphore_line>) or something else, they need to be able to communicate quickly. Also some sort of federalism. I don't think it's even possible to gather the congressmen in one place with a Roman empire type technology. ]
[Question] [ Could a planet's axial tilt change a meaningful amount (what is needed to make inhospitable biomes even more inhospitable: hotter dry hot desert, colder north) over an extremely short period (~100 years), without the interference of technology? To give a little context, I'm building a fantasy world and would like the seasons to gradually "stabilize" in each area, and am particularly interested in making the desert more dire and have it expand a little with desertification of nearby areas; but without making the high latitudes (> 75-80°) more hospitable. [Answer] > > ### Could a planet's axial tilt change over time naturally? ("naturally" meaning without the intervention of technology) > > > Yes, it can. It happens all the time, actually. The best example we have is our own. [From a page in NASA's site](https://earthobservatory.nasa.gov/Features/Milankovitch/milankovitch_2.php): > > As the axial tilt increases, the seasonal contrast increases so that winters are colder and summers are warmer in both hemispheres. Today, the Earth's axis is tilted 23.5 degrees from the plane of its orbit around the sun. But this tilt changes. During a cycle that averages about 40,000 years, the tilt of the axis varies between 22.1 and 24.5 degrees. > > > > > ### If so, what would be the fastest - even abrupt - way it could happen? > > > There are only two ways to do it abruptly (even by geological standards), and those would likely end life on the planet. You see, bending a planet's momentum in any way involves a humongous amount of energy. You could use impactors, but [adding just enough energy to Earth so that we have an extra leap second takes enough energy to end life on Earth many times per second](https://what-if.xkcd.com/26/). Just imagine the mental exercise on that XKCD page, but with the impacts aimed at tilting the Earth rather than slowing its rotation. The other way would be a flyby of a gas giant/dwarf star/black hole, but that would not only destroy the crust, it could also screw the rest of the solar system along with Earth. > > ### Can it happen gradually and not abruptly? If so, is there a chance it could happen over an extremely short period (~100 years)? > > > As seen above, it does happen gradually here - over dozens of millennia. If you could change the tilt of the Earth by one degree in just one century, you would probably cause climate change faster than we are doing today with pollution. In the last 40,000 years, we went through glacial periods and back to "normal" once or twice. Still from NASA's page: > > More tilt means more severe seasons—warmer summers and colder winters; less tilt means less severe seasons—cooler summers and milder winters. It's the cool summers that are thought to allow snow and ice to last from year-to-year in high latitudes, eventually building up into massive ice sheets. > > > [And from the wiki on Milankovitch cycles:](https://en.wikipedia.org/wiki/Milankovitch_cycles#Axial_tilt_(obliquity)) > > Increased tilt increases the amplitude of the seasonal cycle in insolation, providing more solar radiation in each hemisphere's summer and less in winter. However, these effects are not uniform everywhere on the Earth's surface. Increased tilt increases the total annual solar radiation at higher latitudes, and decreases the total closer to the equator. > > > (...) > > Because most of the planet's snow and ice lies at high latitude, decreasing tilt may encourage the onset of an ice age for two reasons: There is less overall summer insolation, and also less insolation at higher latitudes, which melts less of the previous winter's snow and ice. > > > Consider that we are already screwed as it is today. Making climate change on your planet faster than that of 21st century Earth does not bode well for life. Edit due to this comment: > > can you add whether or not it could actually change over 100-200 years? Maybe not a full degree, but 0.5°? 0.25°? > > > We are currently changing tilt at a rate of 0.006 degrees per century. At that rate, species came and went in their own time... Having a change of 0.25 degrees in 200 years would be almost 42x as fast. It would probably extinguish a lot of ecosystems, but I think life could handle it. The planet has gone through five mass extinctions before and here it is, still full of life. At the end of the day I am no specialist, and even if I were I believe there is not enough data nor context to rule out life resieting and thriving in some way, so it is up to you how your world handles that. That being said, the general guideline is that less tilt gives you a colder world (and potentially ice ages), whereas more tilt gives you hotter summers and colder winters on temperate zones (should grant you larger, more abundant deserts). [Answer] > > Could a planet's axial tilt change over time gradually and naturally (i.e. without the intervention of technology)? > > > If so, is there also a chance it could happen over an extremely short period (~100 years)? > > > Yes to both (almost), but the second part is tricky - and even so, it's not harmless. You need a very unlikely impactor: a very large, very fast impactor, that must not hit the Earth (because it would destroy most life on it). It must be large, but comparatively fragile; water ice and loose gravel. Basically a super-comet, several times larger than even the Sarabat comet of 1729. It must hit the Moon, best if at almost a 90° angle, over the Mare Orientale. The greatest part of the ejecta will fall back on the Moon (some will hit Earth, but that should be survivable). The resulting impact will measurably alter the Moon's orbit, pushing it nearer the Earth. The Moon as seen from the Earth will start to apparently rotate (i.e. its rotation will remain the same, but will no longer match its revolution period). The "new Moon" should cause a graceful - except for some earthquakes and tsunamis - wobble in the Earth's orbit, and some of the momentum exchanged will go into altering the axis' direction over the years. ]
[Question] [ I thought of two questions regarding ringworld structures in solar systems with results I can't assume, so I will try to describe each (assume stability): 1. If a (toroidal) ringworld were massive enough, bodies or planets nearby would orbit it in a spiral fashion along its length, as opposed to in discrete orbits "in front of" or "behind" it (I'm picturing something close to a [demonstration made on the ISS](https://www.youtube.com/watch?v=qHrBhgwq__Q) that used electromagnetism but was a close analog to gravitation). What most affects the periodicity of this orbit, and how quick can this orbit occur, if the planet is earth-sized and the Ringworld has a radius of 1AU? Could this orbit be as short as one week, or one day? 2. moved [here](https://worldbuilding.stackexchange.com/questions/79717/ringworlds-and-habitability-on-other-planets). [Answer] ### TL;DR: Yes, helical motion around a ringworld is possible. However, it is far from uniform at larger distances (≥ 0.04 AU). ### Summary of results: For a toroidal ringworld with mass $M\_R = 3 M\_\text{star} = 3M\_\odot$, central radius $ a = 1 \text{ AU}$ and inner radius $b = 10^{-4} a \simeq 15000\text{ km}$ (hence density $\rho \sim 8800\text{ kg/m}^3$, compare with $\rho\_{\text{Fe}}\sim 7800\text{ kg/m}^3$), the relation between the mean separation from the central ring of the ringworld and the time period is given by the following graph: [![T vs $\lambda$ for helical trajectories.](https://i.stack.imgur.com/NDnaE.png)](https://i.stack.imgur.com/NDnaE.png) $\lambda a$ is the distance from the central ring. The equations are fit using the average (square) value of $\lambda$ over 1 year. The median (pentagon) and launch (circle) values of $\lambda$ are also shown. The error bars indicate the minimum and maximum value of $\lambda$. Black → no central star, orange → $M\_{\text{star}} = M\_{\odot}$. The trajectory is indeed helical. [![Helical trajectory around a ringworld.](https://i.stack.imgur.com/a9Ymm.png)](https://i.stack.imgur.com/a9Ymm.png) We can look at the projected cross-section below. The center of the ring is at $x=-1$ (scaled by $a$, not shown), the central ring of the torus is at $x=0$. It is clear that the "inner distances" are bigger than the "outer distances" as one would naively expect. As earlier, black → no central star, orange → $M\_{\text{star}} = M\_{\odot}$. The first graph is translucent so you can see both cross-sections by zooming in. [![Cross sections of trajectories.](https://i.stack.imgur.com/zMXol.png)](https://i.stack.imgur.com/zMXol.png) ### Physics: For simplicity, consider a point particle; if the satellite is too large (how large?) there would be complications due to the Roche limit etc. Replace the ringworld (torus for volume calculation) with its central ring for all other calculations. Let the particle be launched from $(x,y,z)=((1-\lambda) a, 0,0)$. We only consider the regime $0.01 \leq \lambda \leq 0.1$. The lower limit prevents the particle from recognizing that the ringworld has been approximated by a ring and the upper limit prevents its orbit from being perturbed substantially by the star. Suppose initially the radial velocity is zero. The tangential velocity for orbit around the star (initially $v\_y$) should roughly be $\sqrt{G M\_{\text{star}}/((1-\lambda) a)}$. The orbital velocity around the ringworld (initially $v\_z$) should roughly be $\sqrt{g((1-\lambda) a,0,0) \lambda a}$ where $g(x,y,z)$ is the magnitude of the net gravitational field (a.k.a. acceleration due to gravity) as a function of position. We're kind of stuck without a number for $g((1-\lambda) a,0,0)$. The electric potential for a ring of charge $Q$ is given as (Ref. 1): $$ V(r,\phi,z) = \frac{1}{4\pi\epsilon\_0}\frac{Q}{2\pi}\int\_0^{2\pi}\frac{d\phi'}{\sqrt{r^2-2r a\cos(\phi-\phi')+a^2+z^2}} $$ It is easy to obtain the potential for a graviational ring by substituting $\epsilon\_0 \rightarrow -1/(4\pi G)$ and $Q\rightarrow M$ in the equation. One can take the gradient (with a $-$ sign) and find the field numerically. Or one could go a few steps further and actually calculate everything. Using the equation shown earlier for one value of $M\_R$ (orange in graph), one can extrapolate to other values of $M\_R$ using $1/T\propto\sqrt{M\_R}$ (as long as $M\_R$ is not much smaller than $M\_S$) as $$T = 2\pi R/v \sim 2\pi R/\sqrt{g R} \sim 1/\sqrt{M\_R}$$ where $R = \lambda a$. ### Implementation (Mathematica): (Everything is in SI units unless mentioned otherwise.) First we set up the constants. The elliptic integral for $V$ earlier is somewhat nasty and takes a while to simplify, so I simplified it once and replaced the definition with the output of the simplification. ``` G = 6.674 10^-11; EarthMass = 5.9722 10^24; SolarMass = 333000 EarthMass; RingMass = 3 SolarMass; AU = 1.508 10^11; a = 1 AU; b = 10^-4 a; day = 243600 // N; year = 365.25 day; \[Rho] = RingMass/((2 \[Pi] a) (\[Pi] b^2)) ( roughly 8800, Fe \[Rule] 7800 ) ( Math ) VRing[r_, \[Phi]_, z_, MR_] = -G MR/(2 \[Pi]) ((2 Sqrt[( a^2 + r^2 + z^2 - 2 a r Cos[\[Phi]])/((a - r)^2 + z^2)] (EllipticF[\[Pi] - \[Phi]/2, -(( 4 a r)/((a - r)^2 + z^2))] + EllipticF[\[Phi]/2, -((4 a r)/((a - r)^2 + z^2))]))/(Sqrt[ a^2 + r^2 + z^2 - 2 a r Cos[\[Phi]]])); VRingxyz[x_, y_, z_, MR_] = TransformedField["Polar" -> "Cartesian", VRing[r, \[Phi], z, MR], {r, \[Phi]} -> {x, y}]; Vtot[x_, y_, z_, MR_, MS_] = -G MS/Norm[{x, y, z}] + VRingxyz[x, y, z, MR]; gRing[x_, y_, z_, MR_] = -Grad[VRingxyz[x, y, z, MR], {x, y, z}]; gtot[x_, y_, z_, MR_, MS_] = -Grad[Vtot[x, y, z, MR, MS], {x, y, z}] /. Abs[p_] Abs'[p_] -> p; gtotmag[x_, y_, z_, MR_, MS_] = Norm[gtot[x, y, z, MR, MS]]; ``` Let's do a quick sanity check and see if the gravitational field is as expected. ``` imgWidth = 2160; plotAndExport[fname_, plot_] := (Export[NotebookDirectory[] <> fname, Rasterize[plot, ImageSize -> imgWidth]]; plot); fieldPlotXLim = 1.5/Sqrt[2]; fieldPlotYLim = fieldPlotXLim; splot = plotAndExport["field.png", #] &@ Show[StreamPlot[ Chop@(gtot[x1 a, y1 a, 0, RingMass, SolarMass][[1 ;; 2]]) , {x1, -fieldPlotXLim, fieldPlotXLim}, {y1, -fieldPlotYLim, fieldPlotYLim} , BaseStyle -> {FontSize -> 24}]]; ``` [![Gravitational field flow and magnitude](https://i.stack.imgur.com/z2D1z.png)](https://i.stack.imgur.com/z2D1z.png) Looks alright. The first graph shows the "flow" of the field (the arrows sizes are not correct). The magnitude of the field along the $x$-axis is also shown. Now we implement the solvers for the particle trajectory. ``` ( Trajectory solvers with initial conditions ) xi[\[Lambda]_] := a (1 - \[Lambda]); yi[\[Lambda]_] := 0.; zi[\[Lambda]_] := 0.; vxi[\[Lambda]_] := 0.; vyi[\[Lambda]_] := Sqrt[G SolarMass/Abs[xi[\[Lambda]]]]; vzi[\[Lambda]_, MR_] := Sqrt[Abs[a - xi[\[Lambda]]] Norm@ gRing[xi[\[Lambda]], yi[\[Lambda]], zi[\[Lambda]], MR]]; ringSol[\[Lambda]_, MR_, time_] := NDSolve[ Flatten@{Thread[{xs''[t], ys''[t], zs''[t]} == gRing[xs[t], ys[t], zs[t], MR]], xs'[0] == vxi[\[Lambda]], ys'[0] == vyi[\[Lambda]], zs'[0] == vzi[\[Lambda], MR], xs[0] == xi[\[Lambda]], ys[0] == yi[\[Lambda]], zs[0] == zi[\[Lambda]]}, {xs, ys, zs}, {t, 0, time}]; xiFull[\[Lambda]_] := xi[\[Lambda]]; yiFull[\[Lambda]_] := yi[\[Lambda]]; ziFull[\[Lambda]_] := zi[\[Lambda]]; vxiFull[\[Lambda]_] := vxi[\[Lambda]]; vyiFull[\[Lambda]_, MS_] := Sqrt[G MS/Abs[xi[\[Lambda]]]]; vziFull[\[Lambda]_, MR_, MS_] := Sqrt[Abs[a - xi[\[Lambda]]] Norm@ gtot[xi[\[Lambda]], yi[\[Lambda]], zi[\[Lambda]], MR, MS]]; fullSol[\[Lambda]_, MR_, MS_, time_, \[Epsilon]_] := NDSolve[ Flatten@{Thread[{xs''[t], ys''[t], zs''[t]} == gtot[xs[t], ys[t], zs[t], MR, MS]] , xs'[0] == vxiFull[\[Lambda]], ys'[0] == vyiFull[\[Lambda], MS], zs'[0] == (1 + \[Epsilon]) vziFull[\[Lambda], MR, MS] , xs[0] == xiFull[\[Lambda]], ys[0] == yiFull[\[Lambda]], zs[0] == ziFull[\[Lambda]]} , {xs, ys, zs}, {t, 0, time} ]; appendVelocities[solution_] := Append[solution, {vx -> xs', vy -> ys', vz -> zs'} /. solution] ``` We will need a bunch of functions to analyze the time period. ``` ( Examining the period T of rotation about the ring ) ( findPeriod and reconstruct copied from \ https://mathematica.stackexchange.com/a/38221/9332 ) findPeriod[data_, threshold_] := Module[{fs, s1, s = {}, i, a0f, af, pf, pos, fr, frpos, fdata, fdatac, n, per}, n = Length[data]; fs = Fourier[data]; s1 = Drop[fs, -Floor[Length[fs]/2]]; For[i = 1, i < Length[s1], i++, If[Abs[fs][[i + 1]] > threshold, AppendTo[s, i + 1]]]; a0f = Abs[fs[[1]]]/Sqrt[n]; af = 2/Sqrt[n] Abs[fs][[s]]; pf = Arg[fs][[s]]; {a0f, Transpose[{s, af, pf}]}] reconstruct[data_, fp_] := Module[{n}, n = Length[data]; Show[ListLinePlot[data, PlotStyle -> Black], Plot[fp[[1]] + Sum[fp[[2, j, 2]] Cos[ 2 Pi (fp[[2, j, 1]] - 1)/n t - fp[[2, j, 3]]], {j, 1, Length[fp[[2]]]}], {t, 0, n}, PlotStyle -> Red]]]; getOrbitPeriod[solution_, totalTime_, timeStep_] := Module[{data}, data = Flatten@Table[ zs[t timeStep] /. solution, {t, 0, totalTime/timeStep}]; ( Not strictly correct as there are many frequencies but good \ enough for first approximation ) totalTime/(timeStep Sort[ findPeriod[data, 10^8][[2]], #1[[2]] > #2[[2]] &][[1, 1]])]; ( The period T is observed to be linear in \[Lambda] ) \ \[Lambda]TFit[\[Lambda]list_, Tlist_] := LinearModelFit[ Transpose@{\[Lambda]list, Tlist}, \[Lambda], \[Lambda]]; setGraphFontSize = BaseStyle -> {FontSize -> 12}; graphLineWidth = 0.003; graphMarkerLineWidth = 0.005; graphMarkerSize = 6; opacity = 0.5; polygonMarker[color_, n_] := Graphics[{EdgeForm[{Thickness -> graphMarkerLineWidth, color}], FaceForm[None], Polygon[CirclePoints@n]}, ImageSize -> graphMarkerSize]; coloredListPlot[x_, y_, color_, PM_] := ListPlot[Transpose@{x, y}, PlotStyle -> color, PlotMarkers -> PM]; Needs["ErrorBarPlots`"] \[Lambda]TFitGraph[{\[Lambda]list_, min\[Lambda]_, max\[Lambda]_, mean\[Lambda]_, median\[Lambda]_}, Tlist_, color_] := Module[{model = \[Lambda]TFit[mean\[Lambda], Tlist]}, Show[ Plot[Normal[model], {\[Lambda], 0.01, Max[mean\[Lambda]]} , PlotStyle -> {color, Dashed, Thickness -> graphLineWidth}, AxesLabel -> {"\[Lambda]", "T (days)"} , PlotLegends -> SwatchLegend[{color}, {Normal[model]}] , Evaluate@setGraphFontSize, PlotRange -> {{0, Automatic}, {0, Automatic}}] , ErrorListPlot[ (({{#1, #4}, ErrorBar[{#2 - #1, #3 - #1}, {0, 0}]} &) @@ # &) /@ Transpose@{mean\[Lambda], min\[Lambda], max\[Lambda], Tlist} , PlotStyle -> {color, Thickness -> graphLineWidth}, PlotMarkers -> polygonMarker[color, 4]] , coloredListPlot[\[Lambda]list, Tlist, color, {Automatic, graphMarkerSize}] , coloredListPlot[median\[Lambda], Tlist, color, polygonMarker[color, 5]] ]] ``` Finally, we actually run the solvers and see the data. ``` ( Actually run simulations ) ringSolutionTime = year; ring\[Lambda]list = Range[0.01, 0.1, 0.01]; AbsoluteTiming[ ringSolutions = Flatten@appendVelocities@ringSol[#, RingMass, ringSolutionTime] & /@ ring\[Lambda]list ][[1]] ringPeriods = getOrbitPeriod[#, ringSolutionTime, day] & /@ ringSolutions; {ringMaxDist, ringMinDist, ringMeanDist, ringMedianDist} = Transpose[distCalc[#, ringSolutionTime, day/24] & /@ ringSolutions]; TableForm@{ring\[Lambda]list, ringMaxDist, ringMinDist, ringMeanDist, ringMedianDist} fullSolutionTime = year; full\[Lambda]list = ring\[Lambda]list + 0.005; AbsoluteTiming[ fullSolutions = Flatten@appendVelocities@ fullSol[#, RingMass, SolarMass, fullSolutionTime, 0] & /@ full\[Lambda]list ][[1]] fullPeriods = getOrbitPeriod[#, fullSolutionTime, day] & /@ fullSolutions; {fullMaxDist, fullMinDist, fullMeanDist, fullMedianDist} = Transpose[distCalc[#, fullSolutionTime, day/24] & /@ fullSolutions]; TableForm@{full\[Lambda]list, fullMaxDist, fullMinDist, fullMeanDist, fullMedianDist} ``` Making the $T$ vs $\lambda$ plot and seeing the trajectory (graphs in summary). ``` plotAndExport["Tvl.png", #] &@ Show[ \[Lambda]TFitGraph[{ring\[Lambda]list, ringMinDist, ringMaxDist, ringMeanDist, ringMedianDist}, ringPeriods, Black] , \[Lambda]TFitGraph[{full\[Lambda]list, fullMinDist, fullMaxDist, fullMeanDist, fullMedianDist}, fullPeriods, Orange] , PlotRange -> {{0, Automatic}, {0, Automatic}} ] plotAndExport["traj.png", #] &@ Show[GraphicsGrid[{{ trajectory[full\[Lambda]list[[1]], fullSolutions[[1]], fullSolutionTime/7] , trajectory[full\[Lambda]list[[1]], fullSolutions[[1]], fullSolutionTime] }}]] ``` References:* 1. <http://physics.oregonstate.edu/portfolios/Activities/EMActivities/ElectricPotentialRing/RingVSolutions070701.pdf> [Answer] There are aspects of this question which make it quite tricky to answer. The physics demonstration of charged droplets spiralling around a charged knitting needle gives a reasonable idea of the concept you are trying to consider. Any answer will have to substitute a gravitational field for the droplets' and the knitting needle's electrostatic field. This may not be so straight forward. Anyone who knows I am wrong about this proposition, this please jump in and demolish it. It is suggested that the ringworld will need to be massive to have an Earthlike planet in a spiral orbit around the ringworld. While it can be assumed that the Earthlike planet has a mass equivalent to that of the Earth, that's the easy part. Now to look at the unknown factors in this model. The mass of the ringworld is unknown. The velocity of the Earthlike planet is unknown. The ringworld's mass will determine the gravitational force acting on the planet to keep it orbiting the ringworld. While the velocity of the planet will determine its probability in maintaining its orbit around the ringworld. This suggests that the ringworld will need to be extremely massive indeed. Quite likely, the ringworld's mass will be of the order of a solar mass. That is to say a mass similar to that of the Sun. In which case, the ringworld will need to be made of ultradense matter of the type proposed by Robert L Forward in his speculative article "Far out Physics" (Analog, August 1975, pages 147-166). The planet will have to be moving at a high velocity. This is high compared to normal planetary orbits. The Earth orbits the Sun with a velocity of 30 km/s. However, it isn't easy to devise a way of conceptualizing the relationship between the mass of the ringworld and the velocity of the planet in a spiral orbit. This depends on the distribution of mass along the length of the ringworld and the force it exerts upon an Earth-mass planet so that the planet can be kept in a spiral orbit around the ringworld. One thing that is a worry is the fact that the charged droplets all end up falling on to the charged knitting needle. If the same behaviour applies to a planet in a spiral orbit around a massive ringworld, then the planet end up crashing onto the ultradense surface of the ringworld. While this is exciting and dramatic, it won't be good news for any inhabitants of the planet. Any answer that can come with a solution to the problem proposed by the question will need to devise a model that describes the gravitational and velocity relationship between the ringworld and the planet in a spiral orbit in order to timescale of the planet's orbit and, possibly, the stability of this system. Currently the unknown factors make determining an answer difficult. This answer has explored the limiting factors of the problem, but has not been able to propose a solution to the OP's question. ADDENDUM: The main problem is the shape of the gravitational field of a massive ringworld. With planets & stars the gravitational field is concentrated around a point source. The ringworld's field has an extended source. The planet could have two components of velocity. One the orbital velocity around the star, the other an orbital velocity around the ringworld. That would yield the spiral orbit. Now this consideration suggests a possible solution. Assume that the mass of the ringworld is equal to that of the Earth-mass planet in a strip that is 12,742 kilometres wide. This width is chosen because it the diameter of an Earthlike planet. This gives a reasonable approximation for the minimum gravitational field of the massive ringworld to keep an Earth-mass planet in orbit around it. Assuming it has an orbital velocity of 8 km/s as this is the orbital velocity needed to maintain a satellite in orbit around an Earthlike planet (in this case the strip of a ringworld). The planet orbiting the ringworld will have a heliocentric orbital velocity of 30 km/s, which is exactly the same as planet Earth, and this is only one velocity component of the planet. The other velocity component keeps the planet circulating around the ringworld. The combined velocities result in a spiral orbit around the ringworld. The OP can plug whatever dimensions of the ringworld to establish the size of the orbit around the ringworld. A quick calculation indicates that the mass of the ringworld will be 73,966.237 Earth masses (where 1 AU equals 150,000,00 kilometres). Just divide the circumference of the ringworld by 12,742 because we have assumed each 12,742 kilometre strip has one Earth mass. The planet's orbit around the ringworld will be an high orbit. Possibly, something like a forty-eight hour orbit which will keep the planet far away from the ringworld. This should keep the planet safe. Also, the ringworld will have to have a narrow width. For example, around 12,000 km, that's right, roughly the Earth's diameter. Again this is to make the planet's spiral orbit safe. The radius of the orbit from the ringworld is 220,015.79 km. Offhand it's not certain if this orbit is viable. Note: this assumes the orbital velocity is 8 km/s. ]
[Question] [ I am a huge Minecraft fan and just realized, this hasn't been asked before, so I wanted to ask a live-long ([31. August 2009](http://minecraft.gamepedia.com/Version_history/Classic#Survival_Test_1)) question, and pay my obulus to the [Anatomically Correct series](http://meta.worldbuilding.stackexchange.com/questions/2797/anatomically-correct-series). I have done some research, and found this picture: [![Pictureof a creepers imagined internals](https://i.stack.imgur.com/aFqQz.jpg)](https://i.stack.imgur.com/aFqQz.jpg) source: <https://img2.minebook.me/gallery/63097_creeper.jpg> So, these are the more specific characteristics that I am interested in: * What substances or properties can cause a living being to spontaneously explode? (And I mean explode, not only [combust](https://en.wikipedia.org/wiki/Spontaneous_human_combustion)) * The Image above shows a connection of the brain to the explosions source, acting as a trigger. As the neuronal network functions by electric impulses, the trigger for the explosion has to be an electric charge, send by the brain. * If possible, explain the (rather long) 1.5 second delay between the brains charge and the actual, externally noticable explosion. A possible explanation I found is, that the explosion is triggered by an impulse of pain. These are the slowest human impulses, traveling the human nervous system at [0.61m/s](http://hypertextbook.com/facts/2002/DavidParizh.shtml), taking 2.84 seconds to travel the [1.73m](http://www.minecraftforum.net/forums/minecraft-discussion/survival-mode/297157-just-wondering-how-tall-is-a-creeper) from top to the bottom of the creature. Bonus Points for anyone who can give some plausible evolutionary explanation on why spontaneous explosions are a desireable trait for a species, andhow it could evolve. [Answer] Trinitrotoluene (TNT) is entirely formed out of carbon, nitrogen, oxygen, and hydrogen. Since we're talking about speculative biology here, I see no reason why TNT or a similar explosive could not be manufactured by some evolved process. For a solution that exists in nature already: cows produce methane en masse (relatively) in their digestive systems. Methane is a viable rocket fuel, so I'd assume it could serve as explosive. We can imagine, then, a large, possibly pressurized "methane bladder" internal organ occupying a creeper's body. Elevated internal pressure, if necessary, could be maintained by building the walls out of a very dense, thick layer of tensile tissue (some kind of cartilage? tendon?) To generate enough force to explode the creature, methane might be utilized in two ways: 1. Pressurized methane is mixed with oxygen in the explosive bladder, then sparked when needed. 2. Pressurized methane is excreted through vents or ruptures in the body that open up prior to detonation, blasting out methane to mix with atmospheric oxygen in the manner of a fuel-air variety of thermobaric bomb. This could also explain the explosion delay time. For the sparking system, we might imagine something like the shock generating organ of an [electric eel](https://www.scientificamerican.com/article/how-do-electric-eels-gene/) connected to a nerve. The explosion delay could also simply be a matter of the creature deliberating whether or not it really wants to die, heh. I can imagine at least two possible benefits of exploding: * Disperse eggs. As for why they target humans before exploding? Maybe injured people and human remains are particularly good environments for their eggs to incubate. * Root out the enemy. Creepers are (eu)social animals which send out "infiltrators" to track down other social predators (humans) and follow them to their dens. By detonating in a crowded camp at night, they stand a better chance of taking out multiple threats at once when they're most vulnerable, or at least severely ruining their day. A more boring answer is that explosion doesn't necessarily have to be an evolutionary advantageous trait; it could simply be that Creepers reproduce well enough that it hasn't really mattered up to now. But considering their size and probable nutrient requirements (presumably on par with a human), this seems less likely. [Answer] Spores. The creature isn't really a creature at all... rather its a genetically modified host to a fungus who seeks to reproduce by attacking humans. After a human is infected, the colony of spores reconfigure the body into the above shape including repurposing the skeleton of the host into the new form. The explosion is really a design of the reconfiguration, expelling the "human" flesh much the same as a porcupine expelling quills (and other examples in nature). But the primary purpose of this "self destructive behavior" is reproduction... in order to expose the now mature spore colonies ready to infect the next victim. [Answer] I'd like to just say, that exploding is beneficial for the creeper community, if one takes an possible enemy down others have a better chance at surviving. Also it might provide the surviving creepers with something to eat. There is no delay with the detonation as such, since the creature is perfectly able to defuse the charge if explosion would not bring a satisfactory result. Charge could very well be gaseous, I actually have been hoping Mythbusters would do a Minecraft episode. I'm betting on gases and an sturdy internal organs used to house and mix them. Detonation is either by electrical shock, or by pressure detonation, such as in diesel engines. The organ housing a combination of gases at volatile mixture rapidly contracts, and as such causes the explosion. [Answer] So from the information [MatPat gathered](https://www.youtube.com/watch?v=wqKT5R2PXlw), The properties of a creeper already exist in our world. [Peat moss](https://en.wikipedia.org/wiki/Sphagnum) is... 1) The same color 2) The same texture Notch described 3) Contains the key ingredients of gunpowder (sulfur and carbon) (and explode to release their spores) 4) Have great electrical storage potential (like super charged creepers, but I don't know if this helps with the exploding or not). I would hazard to guess that the 'hiss' (aside from game balance reasons), is a chemical reaction that builds up pressure in the creature faster than it can escape till it explodes. (This would also explain how they can cancel it safely as they seem to do) Now, I've never seen a creeper eat, and moving is a tremendous 'waste of energy' So I'm going to borrow some features from a certain fungus. [Ophiocordyceps unilateralis](https://en.wikipedia.org/wiki/Ophiocordyceps_unilateralis) is a fungus with the fun property of 'taking over a hosts mind' before killing it to reproduce. So our creeper could be an evolved fusion of these 2... things... that explode near you to infect you, convert you into new creepers, who than seek new humans to infect. (Why do the hard part when you can just take over someone else's body? X3 It's like a zombie apocalypses! Maybe that's why you are the only human in single player Minecraft?) Another option is that creepers are herbivore... but their body design is kinda terrible for any kind of foraging... So if you don't mind changing creepers to look like green monsters of their hosts, this could totally be a thing! [Answer] The creeper evolved from eusocial insects. There is absolutely no reason why an animal would chase its prey down, only to kill itself by exploding, the only thing that makes sense is that creepers are actually eusocial. Eusocial animals will give their life to protect their colony, unlike most animals. The way that the legs are arranged also suggests an arthropod origin. Some of the legs, probably the middle pair(s), have atrophied and disappeared. Inside the creeper, there are two very special organs. One organ stores methane gas, which is triggered by the second organ, which produces electricity at will, like an electric eel. (A concept that Accelerando mentioned here) When a creeper is struck by lightning, its body absorbs the electricity into the electric organ without igniting the methane. When it does explode, the explosion is much more powerful. ]
[Question] [ Let's say my eyes were ripped out in some horrible accident, and were replaced with cameras. Over the years, the cameras get better and better... 4k... 8k... 16k... etc. Is there a limit to how high of a resolution our brains are able to process? [Answer] # Yes, there is a limit. The camera would have to use the same communication protocol that the natural retina uses to feed into the optic nerve. The [optic nerve](https://en.wikipedia.org/wiki/Optic_nerve) isn’t just a wire like a USB cable. ![vision](https://upload.wikimedia.org/wikipedia/commons/c/cd/Lisa_analysis.png) Rather, it is a processing pipeline. It is actually part of the brain, just arranged in a long strip so that the work that needs doing is performed in the physical space that needs to be filled. We receive not pixels but more like a vector description with perception tags. # But maybe we can use higher resolution anyway? What if you replaced the optic nerve and as much of the visual processing cortex as was needed, too? The result of the whole process might be, for example, to “see” (meaning to perceive after analysis) that there are two edges next to each other. The original retina could not resolve that there were two different edges so the analysis only finds one thick line. But the high-resolution prosthetic eye, with updated analysis circuits to match, resolves two close-spaced features and dumps that information (“there are two closely spaced parallel lines at such-an-angle relative to other features”) to the [visual cortex](https://en.wikipedia.org/wiki/Visual_cortex). # Fake augmentation But maybe science isn’t ready to replace these brain structures. The different (better) retina replacement can have its own processing internally, which then is used to generate fake data compatible with the optic nerve input. Maybe you'll “see” the two lines pre-enhanced or the separation exaggerated; with a general smart zoom feature working to fill your visual input with what’s interesting. The high-res sensor could zoom by taking a subset of the spatial extent rather than subsampling all of it. It could provide a movable fovea; the brain can't handle more data, but you could select which area is the region of interest. Also, note that the retina has cones and rods randomly arranged, not lined up in a neat 2D grid! This is important because it reduces [aliasing](https://en.wikipedia.org/wiki/Aliasing). If the machines are neat grids, you might need higher resolution to achieve the same effect. To provide compatibility, the processing in the eye would clump real pixels to emulate randomly-positioned (larger) pixels. And, it could be auto-adaptive to even better prevent artifacts and improve perception of real details. [Answer] # Human eyes aren't cameras We simply don't "see" in the same way that cameras do. What we actually see in any instant is a very small amount. Our brains do an incredible job of filling in the gaps of our instantaneous perception and giving us a vision of the whole. This is why we're so prone to optical illusions and explains why they highlight how our perception works. [Cameras vs the Human Eye](http://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm) This "gap filling" feature of the brain allows us a huge amount of capability that fools us into thinking we have super-cameras in our heads We are able to: \* Have an almost infinite depth of field \* Instantaneously "see" a scene with a huge range of tonality (say you're in a dark church looking out of the door into blazing sunshine) \* Have a huge range of sensitivity - we're able to sit in an almost dark room and still see enough not to walk into tables. If we were to replace our eyes with high definition cameras, our brains would probably not be able to process the added information. We'd have to completely relearn how to see. [Answer] Bandwidth limits abound. The human optic nerve is [estimated](https://www.newscientist.com/article/dn9633-calculating-the-speed-of-sight/) to be capable of carrying about 8.75Mb/s, give or take. Our "flicker rate" of about 30fps would give us about 291kb/f for each image. Using 8 bits per channel, that means we have 36500 pixels to work with. That's a far cry from the millions of pixels in a modern camera. The human brain and optical channels are brilliantly designed to maximize value out of the whole system. They're not designed for raw data input, they're designed for finesse. We could replace the optic nerve with wires to get more bandwidth. Obviously the brain has more bandwidth to play with than the optic nerve does. However, it's not clear if we could really leverage it. We already spend 20% of our total metabolism on our brain. Doing calculations costs energy. While the calculations on a full camera image are simpler than they are on our organic images, they'd still rapidly swamp the brain. They're not the kind of decisions the brain is good at. Interestingly this energy cost is so pronounced that we actually divide our retinal gangelons into two classes. A small fraction are designed to catch rapid motion, and are updated at a high rate, while the majority are "sluggish," designed to update slowly and catch the whole scene. [Answer] From Wikipedia we learn that the visual field for one eye is (from the centerpoint) about 60° up, 60° towards the nose, 75° down, and 110° away to the side and for two eyes it is 135° vertical and 200° horizontal. We also learn that 1 arc minute is a reasonable resolution, for the purposes of calculation, why not make that 0.1. I'll leave it to you do do the math(Ed note: about 97 MPixel, close to eye [physical limits](https://en.wikipedia.org/wiki/Rod_cell#Structure) ). Of course, this ignores response rate, the ability of the lens to focus at different distances, the ability of the iris to increase the amount of (intensity of) the light hitting the retina, the sensitivity of the retina and the color differentiation of the cones & rods. I've forgotten the number, but it was about 3 or 4. The brain SENDS 3 or 4 times as much data TO the eye as the eye sends back to the brain. In other words, vision is a very computationally dense process. I've seen two things in my lifetime which have amazed me and which are relevant here, I think. I knew a guy who could read a traffic speed limit sign at a distance where the sign (rectangular white) was little more than a dot to me. He had incredible resolution. I knew another guy, (I've noted it in several) who could (and did) "take in" an entire scene in a single glance. Meaning, for instance, he and I would be walking by a room where a meeting was going on, and we'd both glance in. I'd recognize a couple of people and a few other details while he could tell me who was there and what exactly the powerpoint slide of an excel worksheet being shown had on it. (not everything, but an amazing amount of details). In the first case, the resolution is physical (most likely); in the second case he had to have both excellent eyes, and a neural system which was able to process all of that information a lot more efficiently than I can. The take-away from all of this is that there are all sorts of limits on human vision. Some of this is due to the physics of the eye, some of it is due to the processing in the optic nerve, and some of it is, no doubt due to the efficiency of (effectiveness of) the visual volume/area of the brain. One thing to keep in mind is that the processing power of the brain is limited. The more information you extract from one "instant" of stimuli, the fewer "instants" you'll be able to process (everything else being equal). This implies the perfect system would be one which only focuses on the stuff you want to retain. The downside of this is that while focusing on the strawberries, you miss the leopard in the tree. ]
[Question] [ So I'm working on building a city in my world and I've run into an issue with scale/size. I have the general idea of how large the city will be (~8 km diameter) and I am having trouble coming up with a number of residents. As for technology and resources, they have indoor plumbing, cobblestone roads, with most buildings being primarily stone. This city is a thriving center for trade and has abundant resources. Magic used in construction is possible, though limited. They do have access to glass and steel, but using large quantities is very expensive. And their knowledge of architecture is much like our own. So, with these resources, how many people could comfortably live in a defined 8km space? [Answer] Your technology level seems to be roughly 1700s-ish...I'm not sure if that is what you were going for but thats the impression I got from your question. Your city is 8km across, so for a circle with radius 4km, you get 50km^2 area. For a 8km edge square you get 64 km^2. Here are your best comparisons that I could find good data on: Asian Cities Vijayanagar in South India had city walls enclosing 25km^2, and outer walls enclosing 650km^2 which included farmland, gardens, and suburban residences for the rich. It had a population of 500,000 in 1500AD, most of that probably within the inner walls. Beijing's old city walls came in two sets, the inner city and outer city. These were not one inside the other, but two city walls right next to each other, about 2km apart. Together they enclosed an area of about 50 km^2, almost a perfect 8x8 km square except for the gap between the two sets of walls. Both walls were completed by 1550. Beijing's population from then until 1800 ranged from 700,000 to 1.1 million, though by that time many people probably lived outside the walls. The density of these two cities would have been about in the ballpark of 20,000/km^2, so that is probably a good benchmark for your city. Middle Eastern Cities These cities tended to by hyper-dense, and remain so today. Cairo is one of the densest cities in the world, and pre-civil war Aleppo and Damascus were as well. Istanbul didn't grow beyond the Theodosian Walls until the 1800s, except for Galata, across the Golden Horn. I measured on a map and estimate the area to be about 10 km^2. Istanbul's population from the 1550s to 1800 was probably in the 500,000-700,000 range for a density of 50,000-70,000/km^2. I couldn't get good are data for Cairo, but I think its density was in the 50,000km^2 range also at its peak in the 1300s-1400s. Its footprint was pretty small. Cairo had 'skyscrapers' like the Roman insulae, and may have been built up vertically more than any other city before the 1800s. European Cities European cities only had desely populated city cores (of 2-5 km^2) and had more extensive suburbs than China and South Asia. Its tough to find a European city as big as yours with a reliable census figure. Naples, Italy was 484,000 people at the census of 1861 in an area of 117 km^2. The central bits of London (defined here as the City of London, plus Finsbury, Shoreditch, Bethnal Green, Stepney, Holborn, Southwark, and Bermondsey) has an area of 29 km^2 and population in 1801 census of 401,000. Greater London had 959,000 people in an area of 5223 km^2. Paris's administrative limits cover 106 km^2. Its population ranged from 420,000 in the early 1600s, to about 630,000 right before the french revolution. So for Europe, Naples and Paris's density was in the range of 5,000/km^2 for a larger area, while London's inner core had a density about 15,000/km^2, or a little less than the Asian cities. If you want your capital to have more parkland and suburbs, or have a more European/Renaissance character, go with those numbers. [Answer] If the city is 8km wide, and we can assume it's roughly a circle, then it's approximately 50km² in area. Taking from [this site](http://www222.pair.com/sjohn/blueroom/demog.htm) we can approximate 14,942 people per square kilometer. This totals to 750,000 people. I'm inclined to think this number is way too high for a couple of factors that scale up faster than population as you increase population: * Sanitation requirements * Transportation requirements * Resource logistics (transporting food and water to and from the city) * Civil management (law enforcement, taxes, etc) Also a few factors scale more or less directly: * Food requirements * Water requirements Further Paris during the (very late) medieval ages is estimated to be 250,000. I can't hunt down an acre/square km size for it during this period, but it was a larger city. Demographics in detail are hard to come by, so these are just approximate numbers. Keep in mind however many people you place in the city, expect a 5-to-1 up to 10-1 ratio of nearby farmers to city citizens. [Answer] A million people is about the maximum for a city before the invention of mechanised transport, since if it gets any bigger then people can't walk in from the suburbs on any realistic timescale. That's with population densities much higher than in most modern cities, and your 8km radius sounds about right. See Rome in 200AD, Baghdad in 900AD, Kaifeng in 1200AD or London in 1800AD. All around 1 million inhabitants. But they won't be comfortable, because of the need for a very high population density to squeeze everyone in close enough to the centre. If you want to increase that, you need better transportation technologies, not better building technologies. See [this article](http://uk.businessinsider.com/largest-cities-throughout-history-2013-1?op=1?r=US&IR=T) for some more details on the largest historical cities. ]
[Question] [ In the book [The Killing Star](http://bbs.stardestroyer.net/viewtopic.php?t=158707), Relativistic Kill Vehicles ([RKV](http://eclipsephase.com/rkv-weapons-suite)) are described as the ultimate weapon. They are described as impossible to stop, so that any civilization that develops them better start using them against everyone or else risk total destruction itself! I'm brainstorming for ways to defend against RKV. I was thinking that making the orbit of my planets more complicated would make them harder to hit, since it takes some time to accelerate an object to 0.9 c from outside a star system; for this reason if your trajectory is hard to track it gets harder to "aim" the RKV. At the beginning, I thought of making my world a [Trojan moon](https://en.wikipedia.org/wiki/Trojan_(astronomy)) - to add "cycles" to the orbit. Then I thought of replacing my planet with a [Bank's Orbital](https://en.wikipedia.org/wiki/Orbital_(The_Culture)) to reduce its profile. Will adding bodies in a tight configuration (was thinking the hexagonal [rosette](https://en.wikipedia.org/wiki/Rosette_(design))) help with making the system even more unpredictable, while still providing basic stability? [Answer] Making it more "complicated" doesn't make it less predictable. What you need is to make it chaotic. It needs to move in a way that can't be predicted far in advance, either because it is so chaotic that no measurement is good enough, or because you actively mess it up at random. An example of this are the outer three [moons of Pluto](https://en.wikipedia.org/wiki/Moons_of_Pluto#Rotation) Because they orbit a changing off-center primary (a binary object) they orbits don't repeat exactly, although they are held in formation through complex resonances so they don't fly apart or crash. Interestingly, the rotation of these moons is even worse. (Though I knew about Hyperion long before these were discovered, and its chaotic rotation has been featured in science fiction stories.) > > Nix can flip its entire pole. It could actually be possible to spend a day on Nix in which the sun rises in the east and sets in the north. It is almost random-looking in the way it rotates. > > > You want the body's position to be this random, though the tumbling is a more severe form of the effect. So here's an idea to turn the rotation into a position: imagine two rocks on opposite sides of the moon. Their locations in space, if the rest of the bulk was ignored, is random. So make a second-level binary object. The two bodies rotate around each other, but the axis of rotation is subject to this chaotic gravitational torque and precesses all over the place, on a rapid time scale. If they are artificial habitats you could use tethers to directly have a rotating body with a mostly-empty middle. [Answer] ## Active defence The key to this is early warning, you have to know as soon as possible and as far out as possible that these things are coming. The VDA [(Very Dangerous Array)](http://schlockmercenary.wikia.com/wiki/Very_Dangerous_Array) is a good place to start with this as it's self defending and the array nature means it can't be easily knocked out. The sooner you spot them incoming the more accurately you can plot their trajectory and get into position to fire something equivalently energetic back along its path to intercept. If you're really good you could hit it with a much lower energy object across it's path and knock it far enough off course to no longer be a danger. It's a whole lot cheaper than accelerating a planet. If you have multiple VDAs up and they all get knocked out simultaneously, just accept your fate. [Answer] The problem here is two fold: 1. An RKKV is not going to be detectable very far in advance, since it is essentially coming in just behind its light cone. Any sort of active or passive defense will not have much time to react to the arrival of an RKKV. Indeed, if a defense is deployed, it must be totally autonomous, since there will be no time to report to a higher authority. 2. Planets have immense amounts of inertia. Moving a planet is a long and involved process (for example slinging asteroids past the planet to exchange momentum). XKCD has a [useful example](https://what-if.xkcd.com/146/) A Kempler rosette simply has bodies moving in a regular orbit around their common centre of mass, and individual planets, or even the entire rosette are not going to move anywhere very quickly. Defending against an RKKV would probably involve many of the different ideas expressed in these answers being used in conjunction. Clouds of gas and dust would certainly degrade a wave of RKKVs, and the incoming weapons would be rapidly converted to plasma by the intense energy release (see [Relativistic Baseball](http://what-if.xkcd.com/1/) and [Diamond](http://what-if.xkcd.com/20/) for a more detailed description of what happens at these speeds). Any object that is being targeted will need the ability to move quickly, so while it sucks to be on the planet, if you are in a spaceship in orbit around the potential target you blast away at maximum thrust the moment the plasma clouds appear in the outer Solar System. Moving in a random or chaotic path is the only sure way to avoid being targeted, but as noted, with planets you run the risk of colliding with other bodies, which is not going to make your day much better. So the real issue is the mismatch between the time you have to react and the amount of energy needed to actually move a planet. You might also consider that suddenly applying petajoules of energy to a planet in a matter of minutes to hours to get out of the way will also result in massive earthquakes and other geological damage to the world. The most "realistic" answer is the civilization in question may quietly evacuate their homeworld and scatter to low energy enclaves throughout the Oort cloud to deny a lucrative target for the RKKV's, and have a MAD like defense system ready to backtrack incoming RKKVs and launch a counterstrike when they are detected. [Answer] The orbits of your planets will always be predictable from observations if you are not constantly adding delta-V. A rosette will shrink the window of opportunity for some angles, but have very little effect overall. Since we're talking about planets here, any noticeable delta-V is going to be hideously expensive. If you have this energy available, you might as well just add giant thrusters to your planet and zoom around randomly, though at a fixed distance from the star. [Answer] # Defense is Easy Anything coming for you at such speeds will hit dust or gas and produce gamma rays. It will be highly visible. Move small spacecraft out the way or large asteroids in the way. Or hit it with a high power laser. Containing the projectile is hard but atomizing it and spreading out the energy could be done by putting something in the way, even thin solar sails would turn it into a cloud of fast atoms. If they are impossible to stop wouldn't Mutually Assured Destruction stop anyone using them? [Answer] Your best bet might be to redirect the projectile. Create a micro-black hole that could alter the course of the RKV enough to miss the planet. Have it designed so the black hole collapses quickly enough to not be a problem. If you want to avoid black holes, perhaps some sort of strong magnetic force could be used to form a sort of ramp out of smaller particles that can cause enough friction to change the direction the RKV is traveling. [This answer](https://worldbuilding.stackexchange.com/a/6356/16958) suggests that even the smallest particles could cause enormous drag. [Answer] # Dust You turn the entire concept around on the attackers. If a tiny little RKV can kill an entire city, then a tiny little speck of dust can kill an RKV. Any RKV that tries to go through this will explode much earlier than intended. An objection anticipated: but if an RKV his the dust shield, will that not leave a "hole" to shoot through again? Not really no. First the hole will be relatively tiny. So you have a really small target to try to shoot through again. And you cannot send a train of RKV through because the destruction of the leader will create even more dust and debris which will knock out the followers. Second: the dust is not hanging there static. It is moving at several thousand meters per second in order to stay in orbit. And the attacker can never know which direction the dust — and thereby the hole — is moving. You can even have several layers of dust, at different orbits, moving in different directions relative to each other. This means the shield becomes self-sealing because any "hole" punched in one layer will instantly be covered by the other layers. [Answer] ## Dodge. No need to complicate things with more bodies with the planet. If the RKV is already under way, and it cannot be redirected, just accelerate the planet to a slightly different orbit, or further along on the same orbit; the RKV will miss. If the RKV can be redirected, same solution, but don't stop moving: monitor continously the RKV's trajectory, estimate where it will collide, and don't be there when it will pass. Since the RKV is much faster than a planet, it will overshoot if the planet makes a last-minute (er, last-week) impulse. If the RKV isn't underway, just wait. [Answer] When life hands you a lemon, it's time to learn how to make lemonade. Your society has the wherewithal to create and stabilize rosettes. The obvious next step is to create a Dyson Sphere outside the orbit of the rosette. This will serve both to hide the planet locations and to provide power for your civilization. [Answer] Disclaimer: not sure if your question was about using orbits to defend specifically or just defense in general. Decentralization is probably your best bet. The best way to not get hit is to not be a target. Becoming spread out and therefore costly to send RKV after RKV to take out each node in your societal network will become insanely costly and assuming each node in a societal network has the capability to launch RKV back, this also sets up the premise of mutually assured destruction via second strike capability. If you have the ability, having societal nodes not just orbiting planets in a solar system but regularly entering and exiting orbits and slingshot-ing around the solar system (in planetary and/or asteroid orbitals) or even galactic systems would allow for much more chaotic movement if you must defend by orbital maneuver. (though in a solar system, if they just RKV the sun, then the whole solar system is done for. The saving grace is that your adversary would need an RKV at a magnitude to actually consider being able to kill a sun) For sun defense, changing asteroid belt to asteroid shell or belts and use of something similar to the oort clouds as a dust shield I guess could be a good option. (Main point done, tangential thoughts ahead) I'd imagine there would be normal communities on the grounds of planets and in simple orbit around celestial bodies to be able to help resupply each node but ultimately if each node has a self perpetuating ecosystem with only the sun as an input that'd be useful. And probably blackbody thrusters.(iirc bb trusters are aka Nuclear-photonic thrusters?) Whichever way this society is going to be governed is going to be an issue. Each societal node must be highly self sufficient due to all the moving about. I was imagining some sort of Neo-Feudalism or something more akin to the EU or UN. ]
[Question] [ Is there any way to set a kingdom in a forest so that it still is a forest instead of a clearing surrounded by forest? The kingdom must live on the ground, and somehow, if transplanted to Renaissance Europe, would have the social status accorded to kingdoms of that time, instead of being regarded as an "Uppity City" or something. The forest can be as large as needed, but is dense enough to be commonly referred to as a forest instead of . . . a woodland? Precursor Civilizations inhabited this world, and died out because extra-dimensional invaders. Not incomprehensible, but malevolent to currently living lifeforms. [Definition of Forest in Wikipedia](http://en.wikipedia.org/wiki/Forest#Definition) It is on good terms with its neighboring countries, and trades with them. ## Technology of neighboring countries Printing Press Gramophone Mass Manufacture of clothes and metal goods. ## Exports Bows Paper Anything that you can think of that doesn't violate the next list. ## Technologies unknown in other countries (Possible Secret Tech) Guns Computers Human-sized Variable Armament Combat Golem Anything else to be added here you can think of, as long as it can stay secret. ## Other Countries in the World Trades with a Renaissance France Kingdom (Somewhere) Renaissance-era Japan (North) (Somewhere cold, but inhabited) (South) (Unknown) ## Other Geographical Information Could have Volcanoes or Deserts, or anything else bordering the forest, as long as it is geographically possible. Kingdom could slowly be losing land, but at current time, is still a kingdom. # Question Can you make a kingdom in a forest? That's it. The other stuff is stuff that is available if you NEED it for a Forest Kingdom. Sorta like Code Golf. Simplest method for a Ground-level Forest Kingdom, wins. [Answer] I can see this question has already been answered but I'm going to have to strongly disagree with the answer congusbongus gave. I'm not trying to kick up a fuss so let me say why I think its very possible for a forest kingdom of some sort to exist. When you say forest kingdom I assume you mean a fairly sophisticated state based on a high population density and a separate class of aristocracy that did not need to farm due to the amount of produce grown by others that could support such a class, who were then able to provide a ruling structure to weld the state together as well as control external defense, all of this existing in a forest. There is increasing evidence that something pretty much exactly like I just described actually did exist in reality, specifically in the Amazonian basin prior to contact with the Europeans. The main evidence for this is the fact that huge areas of the Amazon have so called 'Terra Preta' (black soil), earth with [high charcoal content](http://en.wikipedia.org/wiki/Terra_preta#Anthropogenic_roots). Terra Preta usually also has signs of broken pottery, as well as other human remains such as middens, really it implies heavy human habitation over a long period, supporting a much higher population level than today. This has been recognized by scholars all over the world: <http://news.nationalgeographic.com/news/2008/11/081119-lost-cities-amazon.html> In fact, from all directions the idea that the Amazonian basin was a relatively low density wilderness before Europeans arrived is under attack, there have been clear indications that big towns and vast amounts of villages once existed in the amazon: <http://news.nationalgeographic.com/news/2008/08/080828-amazon-cities.html> There have even been huge geoglyphs etched into the land discovered from the air, as well as with radar and laser analysis: <http://www.nytimes.com/2012/01/15/world/americas/land-carvings-attest-to-amazons-lost-world.html> <http://www.bbc.co.uk/news/science-environment-31467619> Even roads have been discovered: <http://news.sciencemag.org/2003/09/pristine-forest-teemed-people> a bit more info: <http://www.scientificamerican.com/article/lost-amazon-cities/> <http://www.sciencedaily.com/releases/2010/10/101018074612.htm> <http://www.theatlantic.com/magazine/archive/2002/03/1491/302445/> Now this is all extremely controversial but the evidence is building up endlessly that a complex civilization with a much higher population than we thought possible was spread throughout the Amazon, one that supported major public works and complex trade between them. There's more as well, [Francisco de Orellano](http://en.wikipedia.org/wiki/Francisco_de_Orellana) was the first European to travel through the rain-forest and write about it. For centuries his account has mostly been dismissed as fantasy but in light of these recent discoveries there has been a re-evaluation. Even if we don't take everything he says as absolute truth there are still important clues as to the makeup of the Amazonian civilization, for one there were way more people than would be attested for later, they were experienced in war and had a complex aristocracy. Even today the nomadic descendants of the Amazonian civilizations are known to often have a bafflingly complex social structure and landless aristocracy compared to almost all other Nomadic peoples. This is probably a clue of the past society's social complexity. If you want to know more about the Amazon's past let me recommend a couple of books and documentaries: BBC4 "Unnatural History":<https://www.youtube.com/watch?v=HUXLim2HIvU> 1491: New Revelations of the Americas Before Columbus: [http://www.amazon.com/1491-Revelations-Americas-Before-Columbus/dp/1400032059](http://rads.stackoverflow.com/amzn/click/1400032059) The Amazon was still a forest, but the basis of the agriculture was on trees (in any event it was tough to clear large areas of the forest without iron tools, none of which existed in the Amazon before the Europeans), Charles C. Mann's article in the Atlantic has more info here: <http://www.theatlantic.com/magazine/archive/2002/03/1491/302445/> The BBC4 documentary also goes into the nature of the agriculture as well. (BTW, in case your wondering what happened to all of the one time inhabitants they seem to have been extremely hard hit by the epidemic of old world diseases after the Europeans arrived, which may have killed up 90% of the people living there and caused their society to crumble) Anyway, sorry for being so long winded but this is a hugely controversial topic so I wanted to be thorough. To sum it up, YES, it really is possible to create a complex society within a dense forest, and with the use of trees to cover for field crops. In our reality, kingdoms and complex societies DID exist in the Amazonian basin. [Answer] If we take human history as reality, then the answer is no. In this sole example, kingdom implies large political entity whose control is enforced by a large army which requires a food surplus which implies agriculture, the last of which cannot take place in a forest. Of course this calculus depends on the reality of Earth and human nature, but once those are given, the links are quite strong: * Kingdoms require threat of force to exist, because otherwise why would I willingly subject myself to some dude unrelated to me? The army could threaten to kill me, or protect me from being killed by a foreign army, or usually both. * Armies require food because when they're being an army, they're not very good at acquiring their own food. As they say, an army marches on its stomach. * Food surpluses require agriculture, which is domesticated life forms selectively bred / domesticated to produce more food. There are actually thousands of food crops that have the potential to create enough surplus to feed armies and build a civilisation out of, but in our case they were all terrestrial plants. (There were [nomadic herders who did well](https://en.wikipedia.org/wiki/Mongols) for a while but could never match the population density of agriculturalists, and the latter "won" in the end). Forests are especially poor in this regard as you have all those pesky trees sucking up all the valuable nutrients. Although in our reality, the link between agriculture and kingdoms is quite strong, you could easily shake things up by breaking that link at some step, in favour of forests. Here are some you could try: * Kingdoms without coersion: humans have an individualist/anti-authority streak so they are not willing to submit to someone they deem as an equal. If you change human nature, for example make them more like ants, or somehow create a god-like king, you might make a kingdom without threat of force possible. You could do the same if the humans are under threat from an outside force that humans really dislike, like a different species, although this only ensures unity and not necessarily a king. Alternately, you could add some phenomenon or MacGuffin that only a king /kingdom has. In Ancient Egypt, the pharaohs (and their priestly class) were useful for one thing: [predicting the floods](https://en.wikipedia.org/wiki/Flooding_of_the_Nile), which requires tricky timekeeping and was crucial for agriculture on the Nile. In Ancient China, the legendary [Yu the Great](https://en.wikipedia.org/wiki/Yu_the_Great) got his reputation from controlling the floods, and henceforth all Chinese emperors based their legitimacy on their [perceived ability to control natural disasters](https://en.wikipedia.org/wiki/Mandate_of_Heaven). Perhaps your forest has a magic well and the kingdom is based on rent-seeking, or like the pharaohs there's some hard-to-predict phenomenon that requires intense study by an elite. * An army that doesn't require food: this one's trickier to game, as you need to come up with something else that an army requires, that can only be provided by a large political entity such as kingdoms. Plus, you'll need some reason why the army itself is food-sufficient. One thing you could try is *make your forest denizens natural soldiers**, like the [steppe nomads](https://en.wikipedia.org/wiki/Eurasian_nomads), who learned horseback archery from childhood and are peerless soldiers without extra training. Perhaps instead of horses, you have some forest-animal that is both useful in normal forest hunting/gathering and in warfare. Use your imagination here! Forest agriculture: you could try making your forest fantastically nourishing for some reason, either with some fictional crop that grows in forests, or having a constant external infusion of nutrients. [The Amazon for example gets half of its external nutrients from dust blown over from the Sahara](https://earthscience.stackexchange.com/q/2566/85). [Answer] If you think of the Orchard Kingdom as trees laid out in rows, you are thinking European/Asian. It's only in the 21st C that anthropologists & archaeologists began to recognize that large swaths of the Amazon Jungle are New World orchards, & then spotted this same practice in North America. Not being mad for geometric grids, American natives planted trees in clumps, often mixed clumps, looked after them, then harvested fruits & nuts as they ripened. It was a much less labor intensive way of orchardry. (Can't recall the name of the book, primarily on a lost explorer of the Amazon, early 20th C, looking for a lost city/civilization, who could not see the orchards that were part of its remains.) An orchard is purposely planted, not necessarily spaced out. The trees themselves can provide a bountiful crop with plenty of energy. The Arcadians of Greece were slow to take up agriculture because their oak forests produced sweet acorns as their dietary staple, & they could graze sheep and pigs between them. Give them some long-vine or aerophyte beans & fungi from cloud ears to truffles & I think you're good to go. Houses can be grown out of trees like banyans, trimming the aerial roots to produce walls & hollows rather than letting the hollows fill up with trunk. These provide forest giants whose massive buttressed branches can be used for above-ground lookouts and highways. Also notice that people not used to heavy forest can get lost very quickly. This is easily part of their defences. [Answer] This hangs upon agreeing upon one definition: Can we name a densely-grown orchard a forest? As long as sufficient percent of the trees bear fruit, the whole agriculture can be based upon tree-grown fruit. Especially in tropical regions, properly maintained jungle could provide all the food you need. Wooden housing using trees for structural support would be quite viable. A road network wouldn't need to make a significant dent in the forest, especially if you create separate lanes distanced by sections of the forest. There wouldn't be much of animal farming, but with the right culture limited hunting wouldn't deplete the natural resources, and some farm animals could live off fruit. Fishing and growing macrobiotic fauna would be viable dietary choices to provide animal-based proteins as well, along with fruit and mushrooms of the groundcover flora (which can be farmed to a degree too). The rest goes from there; some obstacles and less-than-optimal solutions but nothing that would prevent it from existing. The worst risk is forest fires. A couple weeks of drought would enable the enemy army to cause a true mayhem. Your world would require either of: * a specific climate that makes it impossible * some very advanced fire-fighting techniques (magic?) * a very good leverage so that nobody would want to do this on purpose, plus a reasonable set of the two above so that accidental forest fires wouldn't run out of control. [Answer] How about something much like the traditional fantasy elf kingdom? * Find a way to make the forest incredibly resistent to logging. Very hard wood, or trees which explode into lethal splinters if you take an axe to them, or incredible powers of regrowth. * Find a way why this kudzu forest doesn't overrun the rest of your world. Perhaps it depends on soil conditions which are only found within the present boundaries of the forest. * Give your kingdom an armed force which is optimized for forest warfare, and much less efficient outside. The trees will break any rigid formation, so perhaps skirmishers with bows/rifles who could not face an unshaken pike square or a cavalry charge in the open. [Answer] Most problematic would be food. As congusbongus wrote in Forest agriculture you can do several things. First is a plant that grows on trees (<http://en.wikipedia.org/wiki/Mistletoe>) or is a tree that is nourishing. Second is an animal that feeds on a trees and can be base of food in kingdom. Lastly you could do a plant that require for some reason forest. Could be magical could be symbiotic relation that is very nourishing. [Answer] As many have said, the major problem with this is getting enough food to support your people: unless your forest is an incredibly rich forest full of a large variety of food-bearing trees, you need agriculture or lots of imports. Importing would be possible, because you can trade your timber for food. Apart from that, it would indeed be possible. Houses can be built using the trees as support; the canopy, while blocking quite a lot of light, would also block much of the rain, so houses could be slightly less sturdy, costing less material and being built faster. Defending your kingdom would also be easy: since your people are used to the forest, they can design strategy around it. Archers can climb trees and shoot at attackers; soldiers can camp up and hide in the bushes, then ambush anyone attacking from behind. [Answer] Yes, a Forest Kingdom could exist. The main problem, as pointed out in most comments above, is food. Foraging is not a sustainable food source for a kingdom, neither is hunting. They are both supplementary. What you will need is some form of agriculture. The point about agriculture is that most people associate it with single crop agriculture. But, in forested communities, like in the Andes, one would most likely find multi-crop agriculture. In one plot of land, say, small, and unploughed, one could grow mushrooms, root crops, berries, etc. All in the same patch of land. You could even be imaginative and take multi-cropping to the trees - vines, fruit, mushrooms, some sort of fowl. So, the food problem is solvable. Now, the second big problem is centralised authority. First, a kingdom can have varying levels of centralisation. A forest Kingdom would, naturally, be more decentralised than an urban civilisational one. So, you could develop complex tribal structures, etc. supplemented by tribal councils. For reference, I recommend you look at some of the work by James Scott. He's an agricultural sociologist, has researched on South American, pre-Columbine, highland agriculture, and on South East Asian kingdoms, both in highly forested areas. [Answer] There are some edible staples that can grow with minimal sunlight on the forest floor. Mushrooms immediately come to mind because they naturally grow in dark, moist environments and [can be harvested 5 weeks](http://www.minq.com/food/4177/20-edible-plants-that-are-easy-to-grow-indoors#page=6). It doesn't take much to grow mushrooms either. They grow in dead animal and plant matter which would be abundant on the forest floor. This, combined with several species of tree that produce nuts, maybe blackberry bushes that are abundant (at least in the woods in southern Illinois which is what I am basing my answer on) and hunting deer would provide a pretty well-balanced diet. I assume the populations would be smaller than the surrounding agrarian societies such as the 'French' kingdom you mentioned. This would actually open up a the [Cities in the trees](https://worldbuilding.stackexchange.com/questions/13768/cities-in-the-trees/13770#13770) idea as viable depending on the size of the trees. I see no reason why a kingdom cannot exist in a massive forest assuming a means to feed the people and create cities is met. And that there are no [giant tree spiders](https://worldbuilding.stackexchange.com/questions/14213/how-to-design-a-flying-tree-spider-and-its-evolutionary-tree). ]
[Question] [ A world much like earth has a society which, although rather aware of metals, does not possess the knowledge or resources to refine ore and produces alloys. They have access to practically unlimited wood and a variety of stone and volcanic glasses, but the only metals they can utilize are whatever native examples are found in the ground. Would they be able to develop semi-robust computing? It would be bulky, but surely not impossible to develop non-electrical analytic devices: it has already [been developed.](http://en.wikipedia.org/wiki/Analytical_Engine) Could it be done without metals, though? More importantly, would it? Assuming the society lived in peace and relative comfort, able to pursue academic issues at ease, and had fully optimized wooden/stone [construction](http://en.wikipedia.org/wiki/Tianning_Temple_%28Changzhou%29) and tools, I imagine would have a relatively developed society. Would they conceive of and pursue the construction of a metal-free computer? [Answer] I note that you ask about computing rather than computers. This makes me consider computing as an abstract process, separate from the modern usage of "computer" to mean a machine. Before we had such machines, [the word computer meant a person who computes](https://en.wikipedia.org/wiki/Computer#Etymology). # Human parallel computing The first parallel computation was put into practice without automated computing machines. For example, during the Manhattan project teams of [human computers](http://en.wikipedia.org/wiki/Human_computer#Wartime_computing_and_the_invention_of_electronic_computing) performed calculations for physical simulations. Richard Feynman improved the speed at which these simulations could be completed by finding a way to split up the calculations so that all of the human computers could be simultaneously working on the same simulation in parallel. These calculations were aided by manual electromechanical adding machines, but in principal the same could be done by a group of humans with nothing but pen and paper and a strict set of rules for how to pass messages. So the answer is yes, a society could develop computing, even without any machinery at all. If your society has access to other methods of speeding up calculation that don't require metal (even an abacus can be used for surprisingly high speed calculation) then teams of people can provide high speed computing services. Over time as people work on improving performance by identifying [bottlenecks](http://en.wikipedia.org/wiki/Bottleneck), more and more of the process may become automated, making use of techniques that we have never had to seek out since we already have metal. In a society without computing machines the people employing these teams of trained human computers would become very wealthy due to demand for the advantages that computing power brings. Similarly to in our world, huge amounts of money could be poured into research into how to improve the computing process. # Example improvements Once individual human computers are capable of completing their assigned calculations incredibly quickly (using aids like an abacus and an extensive knowledge of calculation shortcuts), the bottleneck is likely to be communication. Advances may then include arranging the human computers in geometric patterns that give them quick communication with as many neighbours as possible, and systems for passing messages over longer distances so that they are not restricted to passing messages from one neighbour to the next. For example a system of pulleys and string for connections to a selection of people several metres away, and a system of passing abacus-like temporary stored messages to immediate neighbours. Unlike our electronic computers, which are huge arrays of bits all treated in the same way, human parallel computers may have a large number of separate specialised areas. Perhaps 10 or 20 people arranged to perform a specific function that is used by many other areas of a system of perhaps hundreds of people. # Reliability A system based on humans may sound unreliable, but so is a system based on bits. Errors are common with electronic memory and processors, but error correction is used to make this almost never a problem. Similar approaches could be taken with human computers, including multiple redundancy so that if some people give the wrong results to their step in the calculation there are enough double checks that the overall result is still correct with very high probability. This would also allow for people to leave their position to attend to the need to eat, drink or use the toilet without having to interrupt the larger scale calculation. This makes it simple to arrange for 24 hour calculation - a brief pause at one position while a person is replaced at the end of their shift does not cause problems overall. [Answer] Absolutely. [Mechanical computing](http://en.wikipedia.org/wiki/Mechanical_computer) is indeed a thing. And while our own examples use metal components, they could really be made of just about any material the society could form into the necessary bits and bobs, albeit with some special considerations (e.g. wooden components would be susceptible to changes in ambient humidity, and gum up quickly if liquid lubricants are used). You'd never reach the miniaturization that electronic logic gates can achieve, of course, and computational speed would be limited by the durability, rigidity, and precision of your mechanical components at least as much as by your design itself. But it could be done. There are some limitations. As mentioned, wood is susceptible to changes in humidity (and temperature, while we're at it). This is why woodworks clocks are not, and likely never could have become, precision timekeeping instruments, and similar limitations would affect woodworks computers -- including leading to woodworks computers that won't even work at all except in very particular weather conditions! Stone has other difficulties, primarily arising from the difficulty of making precision components such as gears. That's largely just a function of tools and methods, though, and a sufficiently advanced society that's built on stoneworks would likely have overcome many of these challenges. A stoneworks computer, however, would sound an awful lot like a billion billion fingernails being scraped across a chalkboard simultaneously while it was running! Would a society do this? In one that pursues academic studies, undoubtedly someone would think of the idea and ask, "Could this be done?" And that would inevitably lead to simple mechanical computers -- probably adding machines initially -- which would in turn lead others to ask the question, "What else could it do?" BAM! Computer revolution! [Answer] Yes but they would be faced by certain limitations: * It would be extremely hard to make computers both small and fast - in fact, fast as we understand it, would probably be completely out of the question. * They would be limited in use, bulky and expensive. That would slow down progress in computing sciences considerably. * They might not be susceptible to electrical problems, but they would have all kinds of other problems such as cracks, rupture, wear due to weather and environmental conditions at a much larger scale etc. The primary advantages of silicon and copper based electronics are obviously size and cost first, but they also have the advantage of using electrical potentials which can switch at billions of times per second. It is a well known engineering fact about computers, that making the parts simpler and making them switch faster is far preferable to making them complex and trying to get each to perform multiple jobs at once (as far as computational speed and efficiency is concerned). However, non-electrical computers would be forced to create swiss-army-chainsaws of modules to save space and material, increasing both complexity and operating with water, heat or chemical processes that are far slower in applying their effects, especially without miniaturized components (which often require computers to design and produce themselves). Of course, one can assume light is the switching medium - the problem with light is, the only thing it can switch fast enough is materials sensitive to light and even then it produces microcurrents that require conductors to use. Piezoelectrics and other crystals can be used for this, but they are hard to work with without precision tools (although volcanic glass might allow a workaround). A possible way to make this happen would be to have computers develop over a much longer period of time than in our reality and make them based on light as the switching medium, traveling through glass channels, using glass and crystals as logic gates and hand-crafted arrays of piezoelectrics (pressurized through small pistons? or small enough for light pressure to matter?) or something like that for memory and output. I'm not sure how close to this you can get without metals, or how small, but computers are more of a mechanism than a specific device made of plastic, silicon and doping metals. But if we can make computers in Dwarf Fortress out of pressure plates, cattle and water, I guess it's just a matter of motivation in the end :P [Answer] [Analog computer](https://en.wikipedia.org/wiki/Analog_computer) Without access to metal, but with a robust theory of mathematics, I'd expect to see huge numbers of special-purpose mechanical computers, ranging from specialized wooden slide rules to hydraulic or rope-and-pulley systems for simulating highly complex situations. The general-purpose programmable computer, however, is not likely to appear. [Answer] A society with optimized technological progress in wood and its other resources would most surely become interested in doing math faster at the very least, from there general purpose computers isn't a big leap. They would at the very least give a mechanical computer or water clock a shot. As others have pointed out you can only really push those concepts so far. The space and speed become prohibitive to computation rather quickly and they become almost useless compared to paper and pencil. As far as advancing beyond that we only have to look at our own history to see some routes that might be taken around metals. Chemistry and biology would certainly advance at some point, and the first light bulb used a bamboo filament instead of tungsten. Creating conductive plastics and chemical batteries would seem rather likely. And carbon based computers using graphite and the like would be a direction that could lead to some powerful computers if they managed to snag onto the idea. Possibly even conductive crystals, we do after all use quartz as a key component in many of our modern computers (the clock). Of course, you would probably need at least a little elemental metal to kick-start research into conductivity, they need to start asking the right questions after all! Lacking elemental metal I can see using biology to make computers out of neurons, with chemical soups replacing the need for metal. Possibly even a [chemical computer](http://en.wikipedia.org/wiki/Chemical_computer) could result from that research. This would all require a significant amount of time, peace, and/or luck. With the requirement of a pre-refining society your chemical research would need to stay away from strongly exothermic reactions at the temperatures to smelt, which with the required advancement in chemistry would be highly unlikely. Which places strict limits on the allowed types of natural resource, lack of metal on the planet being the easiest to contemplate. The non-metallic world would need some fairly advanced mathematics and some deep insight into something like lightning on water for example to lead to research into conductivity. So overall it would be almost certain to happen, but very unlikely on a planet with any form of metal. ]
[Question] [ Just as the title says. If you pumped all the air from a balloon and somehow (handwave) kept it from collapsing. Would that balloon produce more lift than a hydrogen filled balloon? How much better would it perform? [Answer] Not very much. 1 mole of a gas occupies 22.7 litres at 0°C. One mole is the molecular mass in grams. Thus one mole of hydrogen weighs 2 grams, and one mole of air is (28 \* 0.8 + 32 \* 0.2) = 28.8 grams. Therefore a hydrogen blimp gives 26.8 grams/22.7litres lift (1.18 grams/litre) and a vacuum blimp gives 28.8grams/22.7 litres (1.27 grams/litre), a difference of 88 milligrams/litre. <https://en.wikipedia.org/wiki/Molar_volume#Ideal_gases> ]
[Question] [ It's common to see "ice beams" that are able to freeze enemies or objects. Freezing a large object solid takes time, so most freeze rays aren't practical or logical, especially after factoring in differences in the material of the object. As an alternate approach, is there a feasible way to snap-freeze water or another substance in a way that it freezes around an object? Is there a practical way to completely surround a human or other large object near instantly with a thick enough coating of ice/frozen material as to prevent movement? Something such as a jet of a two liquids that chemically react and instantly crystallize, but without generating heat. I'm looking for something with an endothermic effect in particular, even if minor. Hurdles to this question include variances in outside temperature (the effect should still be possible in Earthly temperature ranges, maybe 15C - 50C). [Answer] Liquid nitrogen + liquid water Well, actually just about any liquid gas will work here, the best thing to use is liquid helium. Probably. Very little is known about how exactly liquid helium works due to how hard it is to get that stuff. You wanted to be able to encase something in ice. Well, this launcher has the perfect two step process to do it. Step 1: Spray with water to soak it. Step 2: Spray with liquid nitrogen. Now, liquid nitrogen is a minimum of -196 Celsius, but if you want you can do even better - you can take it to around -216 Celsius before it becomes a solid. Now, since liquid nitrogen is that cold, it will draw all the heat from the water it comes into contact with and instantly turn it into ice. Along with anything else it touches. True, it'll produce a colossal amount of nitrogen gas during the process, but if you keep it pressurized and have a thick enough stream of liquid, you'll retain enough cold to freeze the water that you've already fired. This will, of course, result in the demise of whatever organics that come into contact with the water then nitrogen as they're flash frozen and sustain irreversible damage, so be careful not to point it anything you don't want destroyed. [Answer] Supercooled water. [![supercools](https://i.stack.imgur.com/4oT5C.jpg)](https://i.stack.imgur.com/4oT5C.jpg) [source](https://www.bing.com/images/search?view=detailV2&ccid=1zZKQgXs&id=2DCF533ED174DCBB633AB54BB80D0847ED252628&thid=OIP.1zZKQgXsRZjrWMWTVbkCVwHaFj&mediaurl=https%3a%2f%2fi.ytimg.com%2fvi%2fOCRnmBGl-BE%2fhqdefault.jpg&exph=360&expw=480&q=supercooled+water&simid=608006157208912128&selectedIndex=3&ajaxhist=0) This is water that is cooled past the point of freezing. If anything happens to it, it turns to ice but until then it is water. It is kind of like the guy in that Poe story who gets hypnotized when he dies, so he is tricked into still being alive. Ok, just kind of. In any case, shoot this out of a hose and it will turn to ice when it hits your target. It is not exactly like comic freeze rays which in addition to freezing make big blocks of ice come out of nowhere. But this stuff will hit you and wrap you in ice just fine. [Answer] # Liquid nitrogen Liquid nitrogen is very cold. Enough of it will kill you. Dunking something in liquid nitrogen makes it [very brittle](https://www.youtube.com/watch?v=9AYpRMvcBP8). As [YouTube](https://www.youtube.com/watch?v=l1XRspReAvI) shows, a small amount won't do much (don't try at home). If you could first cover your target in water and then cover it in enough liquid nitrogen, you could create a freeze ray. A basic fire engine [like this](https://www.e-one.com/product/commercial-pumper/) can move around 2000 gallons of water per minute. Even with a much smaller pump, you could still wet and freeze your targets quickly. ]
[Question] [ I'm creating a world several hundred years after an apocalypse, but am struggling to get the decay of our current civilization right. The world in short: Earth was hit by an apocalypse in the 2060 (nothing too fancy, just standard nuclear apocalypse with everybody throwing nukes at each other; plus some nanobots going rogue, based on [that](https://worldbuilding.stackexchange.com/questions/14473/sci-fantasy-terraforming-the-earth-and-magic-nanomachines/) question). Several hundred years later, world is quite recovered, crowded with changed animals and demons (mutated humans). Humanity barely survived and is still scarce in the world; there are three to four bigger cities all around the world, several small villages, but apart from that not much. My heroes are traveling through Vietnam and Siberia at some point of the story (Siberia several months or even a year later than Vietnam). Because they need to defend themselves against animals and demons, I came up with the idea to let them find weapons and ammunition stored away in a cache by the Vietcong and (in Siberia) by the Russian army in an old bunker. My question is split in two parts: 1. Can a firearm (preferably a handgun of a type used in the the Vietnam War) and ammunition stored away in a cache in the jungle of Vietnam last until about 2650 and still remain usable or relatively easy repairable? How does such a cache have to be constructed? What about a firearm (handgun and/ or rifle) + ammo stored in a Russian army bunker in Siberia? 2. Can a person repair such a stored gun to fully functional conditions using only handtools that would be carried by a typical scavenger or found in the environment? This might include something like knives or a prying bar, maybe a wire cutter or an axe/ hammer, and also things found in the environment, such as sand for polishing, acid juice from fruits or animal fat. Power tools or workbenches are not allowed. To make it clear, the weapons don't have to be in perfect condition, just restorable. Any rotten wood like a handle or stock is okay, since it can be replaced quite easily. Rust outside is also okay. Just the mechanism and the barrel have to be in such a condition they can be restored easily. Ammunition should be usable, too. The required knowledge for our heroes is not the focus of this question, until it would be necessary to restore nearly any part inside using abilities only a gunsmith has. You can expect them to know how to field strip a gun and solve minor technical problems, since they have seen and used guns before. When they came to Siberia, their knowledge might be grown to a level necessary to understand the inner working and mechanics of an assault rifle like the AK. [Answer] So many negative thoughts! Let's put our creative hats on. 1. Immersed in oil. O2 excluded. What holds the oil? Glazed pottery urns sealed with wax. The oil could be mineral, olive or rice bran. Yes the volatiles may have evaporated and the whole lot set into a nasty waxy mass but I still argue for minimal corrosion. 2. Stored in an inert atmosphere (nitrogen / argon). Containment will be more of an issue but, say an airtight concrete bunker filled with an inert gas. 3. For extra insurance say a combination of 1&2. Of course with option 2 at least one of your party members are going to die when they enter the chamber. The key factors are going to be: * Excluding oxygen * Keeping moisture out * Keeping it cool * Keeping the temp stable I would also note that modern smokeless powders don't degrade the way black powder does. 700 years is a big ask though. If I were to create a scenario I'd go for Siberia. Imagine a bunch of pessimistic Russians (who knew?). 1. They build a bunker in the side of a mountain below the permafrost line. 2. They line it with concrete so it's airtight. 3. They fill it with as many AK47's as they can lay their hands on + tools and spares to service. All packed in ph neutral preservative in sealed containers. 4. They include enough ammo to win a small war (remember standard Russian military doctrine relies on massed fire) similarly packed and sealed. 5. They pump in Argon until O2 levels are minimal. (Also plays to Russian sense of humour - 'Anyone opening this door is going to get a big surprise, nyet') 6. They seal the doors and just for laughs bury the whole lot under a few meters of ice and snow. If steaks good enough to eat can be cut off a mammoth that's emerged from the ice I feel there's at least an even chance some of these munitions will be useable. Have 'at er dudes [Answer] Not unreasonable: <https://en.wikipedia.org/wiki/Cosmoline> Cosmolene is a mix of waxes and oils. Fresh, it's about the consistency of vaseline or peanut butter. Exposed to air, it hardens into candle wax. If you can contain it, vaseline can be used. It doesn't turn into gummy crud exposed to air, but even modest temperatures result in it liquefying and running off. So... applying this principle: Take 45 gallon removable head plastic barrels. Pack with weapons. Fill barrel with cosmoline, vaseline or any low temperature melting point wax. Fasten the lid. Plastic (Polyethylene) doesn't rust. I don't think it is subject to creep. It will degrade from exposure to UV light. A barrel full of guns and wax stored in a cave should be good for centuries. Ammunition. Other sources have mentioned that it would not be good after hundreds of years. Not sure why it would degrade if kept from air. (My suspicion is that the metal crimp at the bullet is not fully air tight, and so air and water vapour very slowly degrade the powder or primer.) If, in addition, you keep it cold, 700 years doesn't seem unreasonable. In general organic chemical reactions have a strong temperature co-efficient, dropping by a large factor with cooler temps. (I recall a vague generalization of a factor of 10 for each 10C change) Surfing some firearms sites the big problems are indeed oxygen and water. A cool dry environment is best. Oxygen eventually destroys the primers. Eventually water and air and trace amounts of NOx in the air causes the brass to corrode. Ammunition stored in Pelican cases with a new greased o-ring gasket, with a packet of oxygen absorber, and a desicant packet then closed it with a lump of dry ice in it, vent open, and up. The CO2 sublimes, fills the case with dry CO2, over flows through the vent. Then close the vent. My experience with the pelican cases is that they are airtight. I have had days when without opening the vent, I cannot open the case. I had closed it on a low pressure day. (The cases are good to 30 feet water, and are warranted against everything but sharks and small children.) More cheaply: The standard military canisters were designed for decades storage, and ones that havent been opened and shut much have very tight gaskets. Just adding a desiccant and O2 absorber to one of these may be sufficient, especially if stored in a constant temperature environment. The largest degradation in this case would be the barometric pressure changes causing the ammo boxes to 'breathe' each inhale bring a bit of oxygen and water vapour in. a container that could deform with pressure changes might be more effective. Say a plastic gas gerry with caps put on with silicone seal. Gaskets eventually dry out, lose their plasticizers, and crumble. Again oxygen is the culprit. A film of grease may add decades to their life. Addition: Zeiss Ikon comments that the primers degrade. And even a small percentage of non-fires will make an awkward pause in combat. Your options: * Special run of ammunition that was designed for storage. It occurs to me that you could make a piezoelectric primer that had enough of a recess that dropping a round wouldn't set it off. On strike, it generates an electric spark. Electronic setups have been tried over the years, but are expensive. An ideal system would have the spark generator as part of the firearm,not part of the round. Alternately you could set it off with a dry cell (easy to make) and a capacitor. * The weapons stored are modern flintlocks designed to use smokeless powder and minie balls. This would play hell with your rate of fire, but if you have guns and your opponent has rocks or arrows the odds are in your favour. * Instead of ammunition, you have an entire production facility mothballed. And while I doubt the ability to keep everything at liquid nitrogen temperatures, I don't think impossible to keep something in a dry inert atmosphere. Aircraft are mothballed in deserts. I don't think the plastic on the wiring would last a long time, but at least there is little corrosion. Mind you, aircraft are mostly aluminum, not steel. * Retarded time field. For the ammo it hasn't been 700 years. Remember all the Faerie legends where someone danced the night away in Faerie, and came home to a hundred years having passed? Only the other way. See Niven's Slaver stasis fields. * You don't explain it. Your protagonists don't know why it still works. Edit addressing some comments: Oils and waxes that are single chain do not degrade very fast. Oxidation on hydrocarbons occurs chiefly at the site of double bonds. The addition of fillers, such as powdered graphite plates can make the effective distance between the surface of the wax and the surface of the metal MANY times longer. This vastly increases the time it takes for volatiles to migrate out of the mass. The mention of polyethylene barrels above was deliberate. PE unlike PVC, has as far as I know, no volatiles. In constant temperature with no UV light, I don't see why it wouldn't last forever. As a checkmark, I have 2.7 mil (.0027 inch) black poly tarp that I put in place on a shelterbelt for moisture control in 2005. It's still intact despite 16 years of weather and sunlight. The average wall thickness of the PE barrels I get is about 3/16" or 167 mills. I would be very surprised if it degraded much in constant temperature darkness. * A lot of material that was recovered from the Scott attempt on the South Pole decades later was still functional. I don't remember if firearms were part of that, but exposed film was, and it developed normally. Cold preserves. * Lot of organic reactions have a doubling in speed for every 10 C (rough and ready rule of thumb) So dropping temperature by 100 degrees would slow degradation down by a factor of 1000. * Consider a heat pipe: Take a chunk of drill stem (3/4" steel walls) 100 feet long and cap both ends. Have a single small diameter port. Run into the ground so that only the top 20 feet are exposed. Partially fill with liquid propane. The propane falls to the bottom boiling. (Could use liquid CO2 also) After enough gas has blown off to be sure that what's left is 99.9% propane or CO2, seal the entry port in a way good for a thousand years. At this point you have a heat pipe that is one way. Whenever the bottom of the pipe is warmer than the top, vapour condenses in the upper part, falls to the bottom, and boils there. Put a ring of these 2 feet apart, around a chamber. Insulate around the outside of the circle of heatpipes. Done properly this chamber will average the 5 year minimum temperature of the location it's in. Given that Siberia has known very cold temps, you have significantly extended the keeping time of your vault. [Answer] If you are at all willing to shorten the timeline of your story, you might be interested to study the history of the Gahendra rifles. These were made in Nepal in the 1880s and stored in the royal armouries. Fast forward to the early 2000s or so and, post-coup, loads of these old guns came on to the market, relatively cheap. Not a bad buy for an untouched century old firearm of somewhat dubious quality. They clean up pretty well and some people do in fact in shoot them. Without simultaneously blowing their hands off. It can get warm and rainy in the summer, cold and snowy in the winter. But the weapons survived pretty well. I concur that anything stored in Vietnam will be a heap of rust after seven centuries; and probably even after one century! But a much better equipped, better constructed Russian facility perhaps with better conditions and higher quality weapons & methods in general might allow for caches of weapons to survive relatively unscathed for a century or two. Ammunition may not last for 700 years, but it could easily last one to two centuries. Anecdotally, I've read a number of accounts of folks happily shooting off ammo of WWII and WWI vintage. The key is how well the guns and ammo are stored, and thus what condition the bunker was left in when originally abandoned. If it was carefully evacuated, left intact and locked up and then forgotten about, your characters might just be in luck! On the other hand, chances are better it will be hastily abandoned, left disheveled and unsecured during the Pockyclypse and will thus be subject to scavengers. I'd just hate to have to wander all up to Siberia just to find a gun of dubious utility! [Answer] The stuff in Vietnam is toast. Pervasive humidity, warm climates, and storing metals do not mix. *The stuff in Siberia might, might* survive, provided they put it someplace that froze over and they used archival grade materials. Plastics, oil, and wood have volatiles that will outgas, and will produce some reactive elements that will destroy the rest of the gun. The metals in firearms are corrosion resistant but nothing made of iron is corrosion proof. Springs in particular will be destroyed quickly as they can't be made as corrosion resistant and still preserve their qualities. Guns often constrain multiple different metals which can cause galvanic corrosion*, because of this don't expect anything that has been plated or contains more than one metal to survive, this even included stainless steel with carbon steel springs so disassembly is advantageous. Extremely low temperatures can slow all these reactions to the point properly stored firearms might might* be usable with a little work if they were disassembled and stayed cold enough the entire time. Wood parts however will be powder due to the dehydrating effects of cold. plastic will likewise decay in the cold as it crystalizes. Note you still want the parts in sealed containers ice is nearly as bad as water for corrosion. Remember the firearms were made by the lowest bidder, they were never designed for centuries of storage. The ammunition is garbage no matter what. Ammunition has a shelf life, reactive chemical in general do not store for centuries. In addition the various metals can actually react with each other exacerbating the process, picture old batteries. Siberia has its own special issues as permafrost is not static it moves, and will destroy any structure built on it and pulverize anything inside it. there is a reason the seed vault is built in sold rock not ice. If they were actively maintained over the years instead of stored they may very well be usable as is, but even the best passive storage makes for very poor conditions. [ideal storage for metals](https://www.canada.ca/en/conservation-institute/services/conservation-preservation-publications/canadian-conservation-institute-notes/storage-metals.html) (the wood or plastic parts can be replaced) is low temperature, low humidity, no oxygen, no salts, no dust, and surprisingly no oil (oil releases volatiles over long term storage). Ideally any wood or plastic parts will be stored separately otherwise volatile coming off them will corrode the metals. They should be stored in thick sealed inert metal (gold) or glass containers filled with inert gas and even then your chances are extremely low. And you run into the issue that such storage is less believable than miraculous survival in poor conditions. Sources [Archival storage of metals](https://www.canada.ca/en/conservation-institute/services/conservation-preservation-publications/canadian-conservation-institute-notes/storage-metals.html) [Plastic and rubber preservation](https://www.canada.ca/en/conservation-institute/services/conservation-preservation-publications/canadian-conservation-institute-notes/care-rubber-plastic.html) [Plastic selection](https://www.nps.gov/museum/publications/conserveogram/18-02.pdf) [Answer] I also doubt modern weapons abandoned in a cache would still be usable in 500 years. But I used to work with a gentleman who made reproduction 18th century duelling pistols for fun - starting with a block of wood and 3 blocks of metal and only using handtools and techniques from that era. Maybe instead of a military bunker your heros could discover a museum with similar reproduction pieces? Modern steels might well last and be useable if replacement woodwork can be made. Gunpowder would be sufficient and is relatively low tech so possible they could either have some already or also rediscover the recipe. [Officially the guns he made were inactive. Unofficially they were authentically accurate, although it turned out that powder from shotgun cartridges was a bit too powerful.] [Answer] I want to address the second part of your question: Can a person repair such a stored gun to fully functional conditions using only hand-tools that would be carried by a typical scavenger or found in the environment... Power tools or workbenches are not allowed While it may not work as well (and probably missing some major features), I am confident in saying this is 100% possible. Improvised fire arms have been made from almost literally everything made of metal. Basic examples: > > [This is a Brazilian improvised firearm](https://www.thefirearmblog.com/blog/wp-content/uploads/2015/08/brazilsmg67846improguns-660x445.jpg) made from a paintball > marker (there is even an office chair tilt knob for cocking handle). > > > [Here is a gun](https://www.thefirearmblog.com/blog/wp-content/uploads/2015/10/TableLegTypewriter1-660x414.jpg) made from a metal table leg. > > > [These Swedish guns](https://www.thefirearmblog.com/blog/wp-content/uploads/2014/11/swedishhomemadesmgs3-improguns.jpg) were made from boat components and a pipe. > > > [This trash bag full of handmade zipguns](https://www.thefirearmblog.com/blog/wp-content/uploads/2015/04/78957568568.jpg) was turned over to > Mexican officials in exchange for cash and amnesty. > > > [This beautifully hand-built gun](https://www.thefirearmblog.com/blog/wp-content/uploads/2015/04/homemadesmgmexico2-improguns-293x390.jpg) was turned over in the same > buyback program. > > > [Here are some guns found](https://www.thefirearmblog.com/blog/wp-content/uploads/2015/08/homemadegunsjapan3-improguns.jpg) when a Japanese was arrested after > producing improvised guns for over 40 years. ([full article with more > pictures](https://www.thefirearmblog.com/blog/2015/09/03/japanese-man-arrested-building-homemade-guns/)) > > > [These were used in an assassination attempt](https://www.thefirearmblog.com/blog/wp-content/uploads/2016/10/koreanhomemadeguns3.jpg) on a South Korean > official, they are almost literally just pipes taped to wood. > > > [Converting old flare-guns into pistols](https://homemadeguns.files.wordpress.com/2014/11/indianhomemadepistol6329improguns.jpg) seems to be a favorite of > criminals in India. > > > [This gun was made to emulate the famous AKM](http://armamentresearch.com/pakistani-ak-style-bolt-action-rifle/) despite only being > bolt action. > > > Semi ironically these [eoka type pistols](https://www.thefirearmblog.com/blog/wp-content/uploads/2009/07/akk.jpg) were made by African > colonies from the expended 20mm cartridges of their oppressors. > > > More complex examples: > > Groups in The West Bank have been covertly producing The "[Carlo > SMG](https://en.wikipedia.org/wiki/Carlo_(submachine_gun)#/media/File:Palestinian_Weapons_Exposed_During_Operation_Brother%E2%80%99s_Keeper_(14256572019).jpg)" which has been used in many terrorist attacks. > > > [Improvised Sten Guns](https://www.thefirearmblog.com/blog/wp-content/uploads/2014/08/homemadestengun-dummyreplica.jpg) have been made across the world from the > IRA to Yugoslavia to Guatemala. (The one pictured was made from just > an angle grinder) > > > Similarly The "[Błyskawica](https://en.wikipedia.org/wiki/B%C5%82yskawica_submachine_gun#/media/File:B%C5%82yskawica_and_other_insurgent_weapons.jpg)", based off the Sten was widely used > by the Polish resistance during ww2. (Top is Błyskawica, bottom is > Sten) > > > The "[Borz SMG](https://en.wikipedia.org/wiki/Borz#/media/File:Evstafiev-chechnya-tank-helmet.jpg)" was widely used by Chechen Separatists as a crude > semi-disposable weapon to ambush police and military forces, after > which they picked up whatever guns they could find. > > > P.A Luty famously/infamously wrote a book claiming it was impossible > to ban guns because people would just make their own, then explained > how he made [this gun from scrap metal and hand tools](https://www.thefirearmblog.com/blog/wp-content/uploads/2017/11/56846795622222-2.jpg) (Image is > of a modern copy made from his book). > > > Summary: This is all to say without a machine shop, a gun can be easily made. Anything that could be salvaged that resembles a gun would make for an even more effective improvised weapon --- Bonus: [Nerf gun conversions from South Africa](https://www.abc.net.au/news/image/6165280-1x1-940x940.jpg) [Homemade AK like smgs from Bangladesh](https://armamentresearch.com/wp-content/uploads/2017/01/2.jpg) [Answer] ## They Would Require a Modern Machine Shop to Restore 20th century firearms were machined to very tight tolerances (typically 1-3 1000ths of an inch). This means that all the moving parts are always in a state of being pressed together. Even if you stored these guns in a perfectly inert environment, within the first few decades of not moving the metal parts of the guns will begin to cold weld together such that after 700 years all the metal parts will become one contiguous block of metal. This means that at the very least, you would need to drill all the screws out, drill out the firing pin, and cut through fussed seams, just to open it up. Then you would have to meticulously clean it, probably re-bore the barrel, and mill new screws, springs, and firing pin. You'd also need to tap and die new threading to screw things back together. This could all be done with the tools a sedentary scavenger might keep in a small workshop somewhere if he could figure out how to get a working metal lathe, but not with stuff you could just carry around on your person. If you tried to do this with hand tools, your tolerances would be too large and you'd ruin the firearm. ## More Reasonable Scenarios The weapon cache may be much less than 700 years old even though the weapon designs are older. I know a few people who still own and fire 175-200 year old fire arms. The trick is that these guns never stopped being taken care of. They have been routinely cleaned and repaired since they were manufactured so they've never had the opportunity to cold weld into a solid block. If these weapons had been maintained by hand tools for the past 700 years, they may still be in working order. I also know people who fire recreations of 300 year old firearms. The other thing to consider here is that there are simply too many people in this world who understand machining and firearms to think that a nuclear war would completely destroy the firearms industry... but it could make them a lot more rare. Firearms would become a cottage industry like they were before the 1800s. So, you may have professionals with tools for making and maintaining fire arms who could have continued manufacturing firearms in a similar fashion to 20th century weapons. In this case, the weapons may be modeled after an AK-47 or what not, but actually be much newer than that. The other solution would be to find a 700 year old workshop along with the bunker. As I suggested before, the tools needed to maintain, or even make a firearm are not all that complicated. Unlike a gun, the components in the tools you will need like a metal lathe or a press are mostly going to be either non-touching, or in configurations that make them fairly easy to torsion free if they do become slightly fussed. The hard part here will again be the lathe. It needs a working motor; so, your protagonist will probably need to improvise something to make it turn. Once he has restored the workshop, he could also restore the firearms. [Answer] I have no problem with the guns being functional if they were packed with long term storage in mind. As for why--some governmental organization hid them there as supplies for special forces units to operate while out of touch. Such weapons would be packed to last and well concealed--they were found because ground movement exposed the cache. Unfortunately, chemical ammunition inherently contains highly reactive chemicals. Highly reactive chemicals will degrade over time no matter how tightly you seal them up. (As will the power sources of any guns that work with inert ammunition.) The only way you can slow this process is with cold--and nowhere on Earth do you have enough natural cold for what you're trying to do. [Answer] # Not impossible. Prepare several large fish tanks in a bunker in Siberia. Cold, but not extreme cold. The bunker is suitably armored. Make the fish tanks airtight using silicone. You have now containers made of glass and silicone, both very, very long-lived. Place the weapons in the tanks, disassembled and cleaned for safety, then flood the tanks with nitrogen gas. The silicone seal ought to be amply sufficient to keep the gas inside. Do not forget to put manuals inside, with lots of easily understood pictures. After the tanks are safely flooded and sealed, a simple clockwork mechanism will open an asbestos-lined copper heat exchanger filled with sodium (also in nitrogen atmosphere) to the internal atmosphere of the fish tank. Now, not only will the fish tank stay oxygen and water vapour free, but any stray molecules that might come inside will be quickly absorbed by the sodium. Like silica gel, but more evil. When someone opens the tank, the exchanger will erupt in sudden but short-lived flame, but that might add to the spectacularity of the discovery. [Answer] Firearms made early than the 18th century had very poor quality steel and poor methods of preservation for the wooden stocks. They had very short lifetimes, especially on the battlefield when exposed to wind, rain, mud, and blood. But today, people collect weapons that were made in the 18th and 19th century, and they are still functional. That's because people learned to make better steel and learned how to preserve the wood. Today, we know how to make awesome steel and other alloys with high hardness and corrosion resistance. Under ideal environmental conditions, firearms that were high-quality plastic and metal construction, like an M-16, would be either viable or repairable. The lubricants exposed to air would have broken down, and the slides and receiver might stick, but cleaning and lubricating and working the mechanisms should make them operational. It's possible that springs might weaken, too. But, I would expect a cache would have a small set of tools and replacement parts of wear-prone items. If the weapons were standard "dirt cheap because they are made of dirt" AK-47 then I would expect that they would be less likely to survive without corrosion and rot making them unusable. But, assuming ideal conditions, many disfunction weapons might be torn down to make a few functional weapons. So, an arms cache buried in a hole during the Tet Offensive would not provide ideal conditions. But a command bunker for the government types might. It could conceivably be sealed against humidity and deep underground where the temperature is low and stable. For Siberia, I would think that Modern Russian caches and depots are as well designed as anyone else's caches and depots, and the weapons would be in good condition. The ammunition will degrade if the temperature varies and humidity is high. So as long as the packaging is intact and everything was cool and dry, it would last for a very long time. ANd, the muzzle velocity produced by the ammo would be reduced, and some rounds might not provide enough kick to support semi-automatic fire -- they jam instead. But, manually racking a round would still work [Answer] I think both regions could use the same scenario to provide what you need. As others have said, the primary issue is going to be general exposure. Oxygen, moisture, humidity, etc. If any of this is present your scenario becomes far less probable with a 700 year timeframe. So we have to get creative. Let's shift our thinking a bit and say they don't find guns and ammo. They find something akin to a parts cache where they can assemble guns and ammo. Many weapons of this era are polymer already, so a wealth of the components for the frames and furniture could conceivably be in tact with little or no damage. Ammo would be useless, and if it wasn't, you wouldn't trust the fail rate on what you find. Each pull of the trigger would be like pulling the arm on a slot machine. But the components to load ammo could easily exist depending largely on how the propellants were stored, or happened to be preserved. Suppose you found an old hunter's lodge in the siberian wilderness that happened to fall below the surface during some freak oil supply run accident that manages to submerge the lodge in ruins beneath the ice and snow, in a pool of oil, freakishly covered and pressured with plastics, or whatever. Suppose the siberian hunter was a nut for oxidation or whatever, and kept the rifles broken down, separated, and air sealed. Barrels, springs, schematics and everything. The hunter had a reloading bench with dies for all the weapons in his own cache, so if you find all that, you may also find the cheat sheet all ammo reloaders keep with their bench, though most hand write that data and the legibility and info may not be as useful (which could help your story). The propellant is a weird one because on the one hand, common gun powder could be made, but your crew would have to know how to do that. And standard loading propellants are almost positively not going to remain effective over this period of time in just about any version of preservation. It has to be dry, cool, and it can't be in a place where expansion is prohibited. Plus, even if you solve the propellant one, you have to consider the primer. So if making bullets is a thing you want your crew to do, you may have to dig in to seeing how one would make a home made primer and home made gunpowder, and see if those resources are reasonably available in your story. But also consider this. Even now gunpowder is practically ancient. No matter what happened in life, and no matter how few people remain, it might be hard to erase the knowledge of this sort of chemistry. Inventing gunpowder and primers may not even be an issue in your world. But thinking of how a building collapses, you could have plenty of well preserved things buried in a chamber where the air around is not problematic as the layers it has been covered in may be the preserving agent, and the junk pile beneath is more or less a collapsed hoarder's room. The broken down guns and reloading equipment was always stored responsibly, in cool, dry ways, with silica, oils, and whatever. And now they are covered in more protection. Just now they are well beneath the surface in something of a nasty honey cocoon waiting for your crew to accidentally knock the right boulder loose and cause a chain reaction that uncovers a few nice treasures. In short, you don't find something that was designed to store weapons. As others have said, if someone knew, it would have been raided or unearthed long ago. Yours might benefit from something closer to an accident that overturned a corrupt officer's personal convoy into a convenient sinkhole in just the right conditions to both preserve the contents of the convoy, bury them, and cause no reason for the people of the time to seek answers and hunt it down. War time tragedies. It happens all the time. Whatever your scenario, you may also be able to get away with not over explaining the hows and whys. Considering that a gun can be stripped down, and regularly are, then the idea of a combination of surplus, polymer, old timers documenting their recipes and things, and reloading supplies, you could conceivably uncover enough parts and supplies to assemble several functional firearms, or like piecemeal ones that technically function, are probably not as effective as they once were, or operate in single fire mode because of x, y, or z. ]
[Question] [ Imagine a medieval-style city, besieged by enemy army. It might be big and have wide river preventing besiegers from direct attack on the walls and launching projectiles significantly far into the city. Besiegers want to use hot air baloons to drop burning projectiles and biological weapons in form of infected meat etc. as well as drop some attackers during nighttime to open the gates of the city. Is it possible for hot air baloons to perform such missions? [Answer] Better for defense. I pondered this scenario in 2009 and posted the same idea. <https://www.halfbakery.com/idea/Siegebreaker_20balloon#1249939283> The excellent comment by Bunsen Honeydew points out that the tethered balloon scheme has more advantages when carried out by the defenders within the city as opposed to those outside laying siege. > > Consider: the besieged are at the center, and the besieging are at > the circumference of a(n idealised) circle. The balloon is anchored in > the city, and the anchor point is surrounded by all the infrastructure > to support it - furnaces with hot air/gas hoses, ammunition supplies, > bucket brigades, pipework, extra fuel, spare parts, winches, > windlasses, mules, encamped technicians, support staff for the support > staff, ancilliary cooks, batmen and wenches, and so forth. Should the > balloon need to replenish itself of any vital supplies, it can be > winched back in to the center. > > > Now consider a change in the winds: the balloon changes tack, but is still (given a few moments of belaying or withdrawing the > tether) hovered above the enemy. > > > In the inverse case, where the circumferential siege-layers are attacking the central hold-fasts, a change of wind immediately places > the weapons platform off-target. In order to reaquire the target, the > anchor point - and all the associated infrastructure - must be moved a > great distance across the landscape around the circumference, or one > must wait until the wind is once more in one's favour. > > > Insert a river, a forest or other obstacle anywhere about the city and the case for the attacking forces becomes particularly dire. > > > I hold, then, sir/madam or other, that this system is inherently defensive, rather than offensive, in the siege situation. > > > — BunsenHoneydew, Aug 04 2009 > > > --- Re size of balloon / @pluckedkiwi skepticism - consider sky lanterns as a smallish example. [![sky lantern](https://i.stack.imgur.com/cljId.jpg)](https://i.stack.imgur.com/cljId.jpg) You could tether a large one of these with a kite string. You could have a pull thread that dumps the fire payload when in position. After the dump you could probably reel in the lantern before it sinks. The balloon will not carry a cannonball. But a wad of flaming grease is more than enough to start a fire if it lands in the right place. [Answer] My initial thoughts are that hot air balloons would be very vulnerable to projectile weapons like cannons and arrows. As these balloons would be primitive, I am not sure how high they could fly or how well they could be maneuver over the target. Another issue is payload capacity. Most of the balloon's floor would be used to burn something in order to create hot gas, that will lift the balloon into the air. Some more space will be occupied by the pilot and perhaps the bombardier. There is a good chance that anything that was on fire and dropped from a great height, would extinguish itself before it stuck the target on the ground. That is assuming that objects could be reliably targeted to begin with. These biological agents would probably have just as much chance to infect the pilots as the targets on the ground. In order to drop of troops, said balloon would have to either land or fly super close to the ground. The light generated by the fire would give away the balloons presence. I think a [trebuchet](https://en.wikipedia.org/wiki/Trebuchet) could accomplish most of want you want to do, with out having to actually leave the ground. [Answer] # Yes, in a way. We have plenty of questions here recently "could a medieval or classical or renaissance civilization X do Y?" The usual answer is "to do it properly, it wouldn't be medieval or classical or renaissance any more." A lone genius or well-informed time traveler trying to do things would run into the limitations of local industry and materials science and try to overcome them. In the process, the civilization would be selectively upgraded. After this general answer, on to the specific question. * Paper hot air balloons are a [party](https://en.wikipedia.org/wiki/Balloon_(aeronautics)#Antecedents) or [educational](http://www.lasgarden.org/pdf/Paper-Hot-Air-Balloon.pdf) gimmick. Party ballons come with a candle inside. (Before you do this at home, check fire hazards and air traffic laws.) * Making such a balloon with medieval technology will reduce the already low payload further since paper won't be the same uniform thickness (or rather, thinness). On the plus side, the candle can double as an incendiary. * Problem, the balloon will go down only after the flame is out. That might be helped if the glue comes apart in flight before burnout. * Targeting will be difficult. * To drop people, it would have to be roughly the size of the [Montgolfier](https://en.wikipedia.org/wiki/Montgolfier_brothers#Piloted_flight,_autumn_1783) balloon and the landing site will be very visible, even at night. Summarized, they can probably get something into the air. It will go down sooner rather than later. Payload will be limited. It will take the effort of many engineers to drop a single soldier. With much later technology, but also with a greater range, Japan tried to [balloon-bomb](https://en.wikipedia.org/wiki/Fu-Go_balloon_bomb) the United States in WWII. That did not work all that well, which is a sign that targeting will be just as problematic with lower technology. [Answer] Attacking balloons could be vulnerable to anti-balloon-ballons: Consider unmanned, small, less expensive and numerous, balloon loaded with a paylod of burning oil and guided by tethers. The attacking balloon's position, even given long tether(s), is to a large extent at the mercy of the wind. If a defensive tather point(s) could be maintained between the attacking balloon and the "sensitive" parts of the city - ie walls/defenses somewhat outside the "main" city walls, defensive balloon could be guided near the attackers and the burning oil (with could also be its lift power source), could be poured into the attacker, destroying it. The agility of the smaller balloon would conceivably exceed the attacker's sufficiently to make attack by balloon difficult. [Answer] Arrows can launch at 280m/s which gives 500m up. I thought crossbows could do better but that's not what I'm finding. (It has been pointed out this is awfully fast--I suspect it should be f/s and someone made a unit error. That doesn't change the basic argument, though.) If your bomber is appreciably higher than that (in case someone has some very strong bow) you're safe. Your bombing accuracy won't be very good, though. If the winds don't cooperate you'll have no choice but to land and haul the balloon around and try again. I don't see how there's a big advantage over simply using a trebuchet to fling the same sorts of things into the city. [Answer] Zeppelins were used for bombing, so yes. Clearly it was found worthwhile. They stopped being used because of heavier than air flying machines. As simple as that. [Answer] The big problem would be the material to make a big enough balloon - paper is out of the question, I saw a documentary on Da Vinci channel on creating a paper hot air balloon able to lift a man. In the end, the glue failed (by the way, the balloon was built into a former airship hangar, which is not quite medieval construction technique). The balloon was about 20m in diameter. European medieval cloth would have been too heavy (I think), so the solution would be silk (primed with some air-proofing substance). However, in Medieval Europe silk was extremely expensive, being at the end of a 5000km transport chain. The solution for "biological warfare" would be to move a mobile catapult (3-5 kg stone thrown) close enough to the castle in the dark, and shoot thingies by half-moon (or less) light. You'd need 6 hours to move it close enough to the walls - maybe on a raft - and a couple of hours to shoot it, then you could abandon it. [Answer] The driving force of innovation is necessity. Siege forces already had an effective method of providing the defending city with all the nasties they could fit in a bucket: trebuchets. Why devise a new method for doing the exact same task? If someone did develop the siege hot air balloon, they would realize they take much longer to deliver the payload, need a return trip for the next payload & are vulnerable to the same city defenses as a traditional trebuchet (unless very high). After the idea was tested, it would be scrapped for more trebuchets. If I was building a medieval army and still intent on investing in research, I'd look for a way to make existing trebuchets more mobile to avoid return fire. But even then, the offensive trebuchets need only aim at an entire city, the defensive trebuchets are attempting to hit one of the opposing trebuchets, or swaths of troops. [Answer] You're not going to produce anything like a modern hot-air balloon, but you don't need to. This doesn't need to sustain several hours of somewhat controlled flight without damage, just get up long enough to cross over the city. A tightly-woven silk envelop (yes this will be expensive) will contain the air well enough to cross over the city so long as there is some reasonable breeze, so you don't need a constant source of heat (which would be heavier than it is worth). They will be completely silent (aside from the noise of the payload hitting the ground/roofs) and only visible as a dark spot obscuring any stars (no onboard flame so completely invisible on an overcast night). Build something like a siege tower to conceal the chimney and obscures the large charcoal fire you are burning under it if you want some kind of subterfuge, else just build the scaffolding. Just as darkness falls, move the opening in the balloon envelope over the chimney (the fire should be roaring hot by now). It will fill with hot air, then you cinch the bottom and loose the tether. Keep the fires going all night and you could get a few off before it gets light enough for the enemy to see them coming. You save a lot of weight by not needing a basket with a pilot (that saves you 100+ kilos of weight which will make the balloon far more plausible), so rig up some time-release mechanism (slow-burning match most likely but water draining through a pinhole will work too). Getting the timing just right will be excruciatingly tricky because of the unknown windspeed, but the bigger the city the wider your margin of error can be. You're not going to hit a specific target, but the city as a whole should be manageable. A tricky bit is having a payload which will be effective in small quantities. A flea-ridden plague rat would be perfect, but how you would get one of those without your own army being stricken is another matter. Incendiaries would be good if you can figure out how to make them well. When the balloon is crossing over the city, the timed-fuse burns out and releases the payload. Drop a rat (goes splat, you don't care, the fleas will survive and spread), or drop a string of hot coals at different times (most reliable given unreliable releases) in the hopes that one will fall into something flammable or even leave a string of fires. Though the balloon will be cooling and falling, releasing the weight of the payload should give it a nice boost to altitude to see it get over the city and out into the fields on the other side of retrieval by morning. If they are lucky, nobody in the city noticed the balloon at all, but the plague will soon spread. If not lucky, the wind is too slow and the balloon doesn't make it all the way over, or worse yet the wind changes direction completely and blows it in a different direction. [Answer] The Japanese attacked the U.S. with this concept during WWII. They used the prevailing ocean winds to blow over some balloons with bombs attached to them. The mechanism was timer based. So very hit and miss. <https://en.wikipedia.org/wiki/Fu-Go_balloon_bomb> Apperantly even Montgolfier suggested to do so 1792: <https://en.wikipedia.org/wiki/Incendiary_balloon> [Answer] It depends on how much technology your "medieval" civilization has Balloons were used for recon during the [American Civil War](https://en.wikipedia.org/wiki/Union_Army_Balloon_Corps), and that wasn't the first application. [France](https://en.wikipedia.org/wiki/French_Aerostatic_Corps) used them as far back as the 1790s. While the early 1800s are hardly medieval, the technology and manufacturing of that time is still very primitive by comparison to today. If your army in question is the first to use this technology, it doesn't really matter if the enemy sees the balloon coming or not, as long as doesn't drop low enough to fall into projectile range. From there, it seems like it should be possible to drop something small but very hot, like Greek fire or burning phosphorous, which would be devastating in a town constructed of primarily flammable material. On the other hand, if this had been effective, I suppose either of the real-world armies listed above would have done it. ]
[Question] [ Closed. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers. --- Want to improve this question? Update the question so it can be answered with facts and citations by [editing this post](/posts/132413/edit). Closed 5 years ago. [Improve this question](/posts/132413/edit) There was an ancient war between two advanced alien civilizations that culminated in a battle over Earth. These two armies destroyed themselves in this final battle, but the fallout indirectly ravaged the planet. As a result, earth has become a wasteland stuck in the dark ages, filled with genocide, slavery, starvation, and all the usual horrors of warfare on a global level. Civilization has regressed back into tribes, each struggling to survive after the apocalypse. This state has lasted for thousands of years. This battle left space debris orbiting the planet, which occasionally falls down to earth. This debris usually contains advanced technology and weaponry, which the inhabitants constantly battle over. The result is a planet occupied by techno-barbarian tribes, each fighting the other for access to this tech and domination over their enemies. Civilization is a hash of various, barely understood tech. Vat-grown abominations made from artificial wombs, cybernetically enhanced amazons, genetically enhanced soldiers, machine drones controlled by A.I., the list goes on. History is filled with various empires rising and falling in quick succession, followed by periods of dark ages. In this chaos, one city state has managed to remain stable through the various millennia by hoarding as much tech as possible. They have gathered the most consistent forms of technology through organization and study. As a result, this city state has the most knowledge and understanding of the tech they use. It wishes to remain neutral in the various wars raging around the planet, and do not take part in the chaos. They are unaligned with any faction, and do not take sides in conflict. To preserve this neutrality, they have agreed to trade technology with various tribes so that all would see a benefit to letting this stare operate. However, While they are powerful, they are tiny compared to the tribes roaming the planet, who could destroy them given enough time. It is well known how this state hoards technology, and is sitting on a vast pile of advanced tech that would make any tribe vastly powerful, perhaps enough to build a long sustaining empire. a strong enough techno-barbarian with enough allies could potentially overthrow the state and take what they have simply with strength of numbers and more technology. In this world where control and domination of technology is the most important thing, how can this state remain neutral and protect itself? [Answer] I propose some explanations for this neutrality : * enormous military/technological advantage (which is, according to your details, likely to happen) * spiritual/intellectual untouchability or supersition : for example barbarians believe the city is holy and gods or monsters punish everybody trying to attack it * economical dependancy : the city is the only place where an essential specific thing is created (drug, fuel, processors, ...) and barbarians could understand that keeping the city alive benefits to all * making alliance with litteraly all surrounding tribes (military defence, material supplying, ...) * physical isolation : the city is really hard to reach so the barbarians think it is not worth attacking it * the barbarians are not united or organized enough to invade the city properly etc [Answer] ## Early in the post-alien-war history, the founders of the neutral city-state discovered the only intact and functional shield The shield-generator (and perpetual power source) is large and not practical to transport, so it naturally encourages "stay here and be safe" over "go out and conquer". This would also limit the size of the "safe" region, which may partly explain why your city-state has remained small. I would propose that this alien shield can switch between absolutely barring entry to the region and temporarily neutralizing all tech along the border. The second option will often be more strategically effective - when your vat-grown abominations control units stop working, or the bionic amazons prosthetic limbs suddenly won't move, or the invading army's energy weapons are suddenly just hunks of metal and plastic, etc... [Answer] Your city-state has the “Sword of Damocles”. A extremely powerful and accurate weapon system that can take out any tribe (or at least its leadership) at any time. No matter how and where they are hiding. (I’m thinking about an orbital launcher platform with tactical nukes that they have remote control off. Or something to the same effect. Literally having the sword hanging above their heads....) Everybody else knows they have this tech. They have used it a couple of times in the past to take out a particularly obnoxious tribe. And they are not afraid to use it again. And that is also widely known. Of course, they do offer neutral ground to all tribes as a major trade hub and offer repair facilities and they will sell some tech (the least dangerous to the city-state stuff) to everybody who comes with peaceful intentions. But there is always “the weapon” hovering ominously in the background to make sure the barbarians act in good faith. [Answer] Neutrality itself isn't very hard to achieve: they need to refuse any and all offers of alliance by any of the existing techno-barbarian tribes and make it widely known that they won't associate with anyone and only wish to be left alone to live their lives. And make sure to avoid any gesture that could be interpreted as an alliance at whatever level with any of the tribes. That would require either some high-level diplomatic skills or the application of overwhelming brute force; ie vaporize any member of any tribes that get within a certain distance of the city-state, no questions asked. [Answer] Trade The city hoards as much as it can. The tech it has already studied, and has created the means to reproduce, and aren't too devastating to be a problem to the city itself, it trades out to the barbarians, irregardless of tribe. It maintains neutrality in that it offers its services to anyone. The city operates its own specialized army of spies that operates through subterfuge. These units scatter themselves between other tribes and steal what tech they can from them, and also scouts for potential buyers. The tribes themselves understands the value of the city existing, in that they can get their hands on weapons that they otherwise would not, due to rivalry and hoarding. Those that do business with the tribe may offer extra to keep their own findings a secret. Tribes that attack the city find themselves being opposed by other tribes which benefit from the city, and most consider it not worth the risk. The problem happens when one tribe gains something so valuable, the city gaining knowledge of it becomes a threat. They might try to seriously upend the city despite the risks. The spy network keeps an eye out for such high level risks and attempts to take preventive measures, spreading propaganda to get other tribes to attack it, while also trying to steal the tech during the chaos. [Answer] 1. Think Switzerland. Centrally located with difficult terrain and narrow trade roads, easy for a single wagon or light truck but difficult for armies. 2. Strong point defenses with limited throughout. The city can reliably take down some finite number of attackers, vehicles, or projectiles per minute. In theory a coordinated mass assault from multiple directions could crush them. Some famous conquerer tried in the past, but got the timing wrong and suffered huge losses. No one has tried since. ]
[Question] [ So, here's my situation: my first book revolves around an unknown entity giving modern day humanity an assortment of supernatural powers. Every week a new power is given to everyone on Earth over the age of 13, and they can hold up to 6 at a time. Once they hit 6, they choose which of the ones they have will be replaced by the next week's power. In addition, everyone has a few permanent powers that don't count towards this 6 power limit and cannot be removed. By the end of the first book, a full year of humans getting powers society can't handle humans having, combined with a few powers seemingly intentionally designed to destroy the world's infrastructure, have knocked the world down to the tech level of your average zombie apocalypse. The entire world's infrastructure (power lines, phone lines, internet, water treatment, etc) is now in ruins due to a previous power, and any attempt to fix it is pointless because now one of the permanent powers that everyone over the age of 13 has is the ability to temporarily disable any technology they want to as long as it's in their line of sight. Which also means that they can't even rely on most modern means of transportation. For more information on how this anti-technology power works, see [here.](https://worldbuilding.stackexchange.com/questions/111411/how-would-one-design-infrastructure-in-a-world-where-people-can-disable-technolo) But stated simply, people can still use modern technology if they can get the fuel or electricity to power them, but if anyone who's looking at it wants to, they can temporarily make it useless with just a thought. That's the bad news. The good news is that everyone over the age of 13, male and female, has the strength of two men, is four times as durable, is immune to disease and aging, and can heal from any injury that doesn't kill them in a week at the longest, all with no added calorie intake except for regrowing lost tissue (these are the permanent powers I mentioned earlier). So here we come to the main issue: rather than the usual post-apocalyptic plot of the main characters making a pilgrimage to the ultra-rural countryside and hoping to find a place where they can grow food, I want the main character's small suburban hometown to turn into a sort of post-apocalyptic city-state run by a local billionaire who, for his own reasons, stockpiled the necessary supplies to make the town self-sufficient enough to feed and defend themselves. Is that possible? Is there enough land in the average small suburban town that, if given the tools, seeds and other supplies, people with the powers described above could grow enough food to support the town's pre-collapse population? And if not, what is the fundamental obstacle they'd face which I'd need to create a power to compensate for? [Answer] You might be able to make a living farming in the suburbs, but that will be very difficult and impractical for the following reasons. Existing infrastructure problems: farming, water, planting I assume there are still houses and roads in the suburbs, as well as (no longer useful) power lines and water lines. In order to do any useful amount of farming, you are going to need a large area of land. To get that land, you will have to tear down houses and pull up roads. Even the foundations of the houses have to be destroyed in order for the crops to take up roots. All of the rubble left over has to be cleared. Even if your superhumans are up to the task, it could take weeks or months to clear a large enough space for farming. Water With no electricity and a bunch of living EMPs walking around, the water supply will no doubt be unavailable. If you live in a climate with good rainfall and have drought-resistant crops, food production should be fine. You might have to construct irrigation ditches, which superhumans will be able to do. Humans, however, cannot grow roots [citation needed], so you need a way to get water. Modern wells use electricity, but a well with a bucket, a clean stream, or a natural spring will suffice. Planting Farming will be super labor-intensive. You don't have planters and harvesters because they don't work anymore, so farming will have to be done by hand or by plow. People will spend most of their time farming, and even though they will be super strong and won't need any extra food, there will be a lot of people and land area limited by point 1, so the agriculture there will be intensive subsistence agriculture. Alternatives Even though you could technically farm in the suburbs, it is very impractical. I fail to see why your people wouldn't just move to the farmlands and farm there. Everything is already set up for farming- there are wells (powered by electric pumps, but that can be fixed), livestock, prepared farmland, stockpiles of fertilizer, plenty of seeds, and large land areas. The only thing that would stop people from the classic fleeing to farmland routine is making the move or farming cost-preventative. Either it is too difficult to get there, or the land is ill-suited to growing crops. The key isn't to make suburban farming easier, it's to make rural farming harder. If your people can't go to the farmland, another good idea is scavenging. Here is what my routine will be for an apocalypse occurs that does not have zombies (if there are zombies, I'll go to rural areas.) When the power goes down, walk to your local supermarket and eat all of the ice cream and frozen foods. Once those are spoiled, eat the fruits and any meat that hasn't gone bad yet. Next to go are the deli items like cheese and preserved meats. Finally, when those are rotten, you eat the canned goods and packaged food like chips, soup, cookies, and peanut butter. Using this strategy, you have food for at least 10 years, which is when some of the aluminum cans will lose integrity and the contents will mold. If you ever run out of the food type you are eating, just walk to another grocery store. After 10 years, some of the cans will still be intact, and hopefully large game (and small game too) will have moved into the area which you can hunt. Given all of these reasons, you need some good explanation for why farming in rural areas is impossible and neither is scavenging. [Answer] # A suburban city; probably not This basically boils down to a population density metric. First, how much land does it take to support each person? This questions is [addressed here](https://worldbuilding.stackexchange.com/questions/9582/how-many-people-can-you-feed-per-square-kilometer-of-farmland). [This answer](https://worldbuilding.stackexchange.com/a/59837/23519) (to that question) shows that the for the US, 10 acres of farmland feed every person, while [worldwide](https://worldbuilding.stackexchange.com/a/88087/23519) 2.2 acres is sufficient. Lets say with a mostly vegetarian diet, but land use practices that allow for some land to not be in cultivation (trees, houses, creekbeds etc), we can feed our population on 2.5 acres per person, which is 100 people per square kilometer. What is the density of your suburb? Most suburbs are significantly higher than this. A populous, built up suburb like Arlington, VA is obviously not going to work, with a population density of 3500 people per km$^2$. A big, old suburb like [Aurora, IL](https://en.wikipedia.org/wiki/Aurora%2C_Illinois) will not work either, with a population of 1730 people per km$^3$. # A suburban county; yes! Better than an older suburb might be to consider a younger suburban county. Here are some examples of counties in the US that would fit the bill: * Walton County, GA (88,000 people; 45 miles from Atlanta) * Johnson County, TX (168,000 people; 25 miles from Fort Worth) * Fairfield County, OH (146,000 people; 25 miles from Columbus, OH) [Answer] It is technically possible, and was actually encouraged during the Second World War in the form of "Victory Gardens". Because of the limitations of size, location and manpower, "Victory Gardens" were generally used for raising vegetables. During this time period, it was also relatively common to raise some chickens in the yard, for a source of protein. The size and manpower constraints eliminate many other possible crops, like grains, and the ability to raise larger livestock, or enough livestock to really make a difference. Using modern technology, it will be possible to make a Victory Garden and raise some livestock on a typical suburban yard. Soil can be enriched by composting the waste products of the garden, watering can be done through "drip irrigation" in order to carefully metre the amount fo water needed. Soil preparation can include mulching, or laying fabric over the soil to prevent weeds from taking root, and protect the soil from erosion and extremes of temperature. Livestock will be changed from large animals like cows or goats, in exchange for rabbits or other small livestock. Plants will need to be protected from insects and vermin, which can be done with frames over the plants and fine mesh netting. Planting complimentary plants like marigolds which many insects find distasteful can also help. This sort of farming does take a lot of work, so you post apocalyptic farmers are not likely to also be spending much time on unrelated ventures. [Answer] Factors to Consider Using purely organic methods with no industrialization and assuming an optimum growing season it takes about one acre of land per person to sustain a food supply. Dependent upon climate, crop choice, water resources, and pest activity this is a minimum estimate. One would preferably have more than that, but they are limited by the fact that they do not have industrial equipment. Granted I am generalizing quite a bit here, but even then the math doesn't really add up to support a modern population. I'm assuming that a pretty good majority of the population have died and the survivors are clearing out unused land in what used to be the suburbs to grow food, and even then this food is only one of a few sources. Not That Far Off With Migration Pattern Estimates Contrary to Hollywood opinion and DOOMSDAY Prepper gospel, the countryside is not usually the best place to go to, nor is it usually the place people tend to flock to in most disasters. Outside of scenarios involving urban warfare, people actually tend to migrate from the countryside towards urban areas instead of vice versa. This is due to a wide range of factors but primarily it is because urban areas are the first to receive aid, the last to lose government, are the most likely place to find employment, and tend to be restored to order first. In places where the state has failed and order has broken down almost completely the countryside is often quickly made dangerous by roving bandits thanks to a low law enforcement and government presence, which means aid is the last to reach there (if at all). Not only are the rural areas usually the poorest, they also don't posses any sort of industry or economy that pays people so they can buy the stuff they can't make themselves. In modern disaster history we have seen that rural areas are the first to go bad, and the last to organize and get better. Even in the most cynical and dire disaster scenarios people still use money (barter economies are mostly a fantasy, in all recorded disasters money or precious metals used as money have been used). You need to go to where money is to make it, and that is usually the city. A Realistic Scenario The suburban dwellers are knocking down empty houses and using parks and whatnot to grow supplementary food. They work jobs for whatever power base exists to buy food produced outside the city by the country dwellers who did not or could not migrate, who tend to trade the food for currency (probably backed by gold or silver) which they use to buy things in the city when they drop off stuff they are selling. The farming occurring in the city is not the primary food source, it is a way to supplement a families diet and lower costs. "Cities" are empty husks of their former selves population wise, no larger than 100,000 people, and that is pushing things. [Answer] Sorry to Disappoint... You are trying to combine low technology with high-density/high-intensity agriculture. Those things are mutually-exclusive. The more intense the farming activity, the more you need external input (fertilizer for depleted soils, antibiotics for rampant disease, anthelmintics for parasites due to overstocking). Trying to produce enough calories to live on either requires lots of space so you aren't overstressing the immediate ecosystem or lots and lots of intervention. You aren't going to organically farm half an acre, or even a couple acres, and support a family. A math problem I'll use sheep as an example because that is what I am personally familiar with. On REALLY good pasture, I can support, without supplemental feed during the growing season, about 6 sheep per acre. Each of those sheep weigh about 120 pounds. When butchered, I might get 35 pounds of meat after boning (I'm being generous here I think). 1 pound of mutton is about 1335 calories, so each of those 6 sheep is enough to sustain your average adult eating 2,000 calories a day for 23 days. One person will consume all 6 in 132 days... Or almost exactly one third of a year. Even if you could survive on 1,000 calories a day, you wouldn't make it an entire year. But wait... I said one acre is enough to support 6 sheep during the growing season. In most places your pasture isn't going to grow year-round. It might grow 6 months before drought or cold or whatever causes growth to temporarily stop. That is going to require storing feed (in the form of hay) to get through those times. Your sheep will love to waste your hay (50% will end up on the ground) and hay loses nutrients as it ages (especially when left in stacks, which is what you will do without technology). So... each acre of pasture sheep is going to require another 3 acres of hay. We're up to 4 acres now. But wait... We just ate all our sheep. We need to make sure we have not only enough to eat, but enough to produce more sheep. My sheep would average 1.75 lambs per bred ewe, so to make sure I had 6 sheep available in perpetuity, I'd need to have 4 bred and producing lambs at all times. Now I have 10 sheep, so I need 1.66 acres of land and about 5 acres of hay... we're up to 6 and a half acres and I still only have 9 months of starvation-level calories. But wait... expected losses are 20%, so now I need to breed at least one more sheep... By the time it is all said and done, I probably need to raise 10 sheep per person in my household. At any given time some will be bred (5 month gestation period), some will be babies (not big enough to eat... that is going to take many months on pasture), some will die, and some will be candidates for eating. Realistically, I probably need 10 acres to effectively raise enough livestock to sustain a small family. I could augment that by planting fruit trees and grazing my animals between them, but of course that shade will reduce the rate of growth in my pasture grasses so now my 10 acres supports less livestock. I could replace sheep with cows, but now I can only have one animal per acre or two. But waitaminnit! You ask how we get (or used to get before inflation anyways) all this cheap meat at the supermarket if it takes that much space. Well, that is where technology comes into play. Once a steer is big enough we ship it to a feed lot. These guys are packed in with very little space, and feed (hay, sileage, grain, supplements) are trucked in from external sources, and the cattle stand around and eat and get fat until they go to slaughter. That works because in our society we have the ability to transport the inputs, we have a lot of pharmaceuticals to keep the animals alive in an environment which breeds disease and parasites, and we have a way to transport the meat around the country after slaughter. This is a little bit of an oversimplification of the process, but you get the idea. Without semi trucks full of feed and syringes full of medication, the practices we use to feed our modern society don't work. There is a reason why, before technology was what it is, herds of sheep or cattle were taken to graze huge areas of land (the "open range"). In fact, this practice still exists. It simply isn't feasible to raise enough animals on small acreage in a sustainable fashion. Without a greater ecosystem, which includes ample farmland as well as perhaps the ability to hunt, fish, and gather, your people aren't going to live much past the immediate food supply. [Answer] Sure, indoor hydroponics. If your billionaire stockpiled everything that was needed ahead of time, you should be pretty set here. Being indoors, it is shielded from the sight of those wishing you harm. Being hydroponics, it removes a great number of the constraints on the growing efficiency of land. You wouldn't even require a lot of extra power if done properly (concentrate the sun with mirrors/light pipes) and moving the water necessary could even be done by hand, eliminating most technology anyways. And since your billionaire was such a good thinker, he even stockpiled [lasers with fiber optic light pipes](https://photonics.gsfc.nasa.gov/tva/meldoc/SPIE/2011/SPIE-2011-High-Power-Fibers.pdf) which possess the capability to blind, even through eyelids. These can be arranged in a manner at key defensive locations in a way which makes them impossible to see until the beam has already burned out the retina, thereby preventing them from being seen and disabled. Since the lasers are not located where the fiber is, their technology defeating powers outlined in your other post are rendered useless here. Whether you mop up the survivors then and there or let them heal in a week doesn't matter much, you're well protected. Sure, they could put something opaque over their faces as they are attacking, but this gives you a much better advantage when defending (aka they can't see you so you can use technology and they can't). Making optical filters in this society sounds pretty far fetched unless some other billionaire stockpiled the resources ahead of time, so even shielding in the particular wavelengths of our lasers would be difficult (aka no miracle defensive glasses). You're safe until blind teleporting is a power and you're overrun by hundreds of people stuck in walls/floors until one lucky one gets in to your hydroponic area... [Answer] # Not Enough Nitrogen and Land The [Haber process](https://en.m.wikipedia.org/wiki/Haber_process), which produces nitrogen-rich fertilizer, is really the reason why we have enough food to go around today. No industrial farming happens without that, and no industrial farming means famine! Even if people do turn their little half acre suburban lots into farmland, there will not be enough to go around. A [person needs to take anywhere from 5 to 10 acres of land](https://permaculturism.com/how-much-land-does-it-take-to-feed-one-person/#:%7E:text=A%20person%20needs%20about%205,comfortably%2C%20producing%20their%20own%20food.) to feed themselves for a year. This depends, of course, on which land you considering and what their diet is. The average suburban lot is well below the 5 acre minimum, which means that suburban gardens, not matter how successful, will not feed a modern population. # Making it Work With Superpowers This situation can work with certain super powers. This is very much cheating on the whole "post-apocalypse" genre and essentially re-creates society using superhumans instead of machines. One of these powers involves nitrogen fixation (which could be the basis of flora-kinesis like [Poison Ivy](https://en.m.wikipedia.org/wiki/Poison_Ivy_(character))). People will need to actively opt for that power. Another set is super strength and speed (or flight). This could form a transportation network for goods produced by those, well, "farmers." Get these "truckers" to carry goods in backpacks, wheelbarrows, or even modified car chassis, and you now have human powered transportation networks. Combined, these can essentially re-create modern farming and rail/truck networks. This does require some coordination and a general sense of society. That goes against many of the typical themes of a post-apocalypse wasteland, which is all about how society collapses. Brushing genre conventions aside, we now we have an (arguably) green farming and transportation economy! ]
[Question] [ I'm working on this concept. A floating island a mile long and 200 meters wide that would travel eternally in a wide circle between Western Europe and the Americas. I am going to make some diferente questions about this concept. My preliminary description of this is as follows: ## Preliminary description of the floating island 1- Epoch: during the Roman Empire, approximately 100 BC to 300 AD. 2- Manufacture: it would be made of Roman concrete, which can resist the effect of sea water for centuries. Its exterior appearance would be "rocky" and in its interior there would be large hollow compartments to give it buoyancy. Concrete boats exist today and are very strong but not very popular. Modern concrete doesn't last long at sea, but the Roman does. 3- Route: a priori I believe that the circuit of currents of the Atlantic Ocean would allow this island to travel in circles from one side of the sea to another without stranding with only a minimum of human control. I'm not sure if a boat of this weight would be controllable with sails or paddles, but we could have a handwave engine. 4- Economics and politics. It would be inhabited by a small tribe of merchant-navigators. Maybe Phoenicians, Carthaginians or Hebrews. When the "island" approached Hispania they could trade with the Romans using smaller ships and in the Caribbean they would trade with the Amerindians. 4-1- I think that the economy of this small nation would be viable as a bridge of merchandise between the two continents, without cultivating or fishing more than a small percentage of its food. 4-2- I supose that this small nation would be able to defend its island from possible invaders, Romans, Celts or Caribbean, but I'm not completely sure. 5- Ecology: with the help of gardeners, an island like this one could maintain thick vegetation with only large ponds to store rainwater. Obviously the technological and economic elements of making such a big "island" out of concrete in Caesar's time would be totally handwaved, but I will appreciate your opinions. My first question about this concept is this: (1) Could this island be made of roman concrete or some other "rocky" material known by the most advanced peoples from the Antiquity? [Answer] While concrete ships, boats and even canoes have been made, I'm not clear if people in the ancient world would have the understanding or desire to build ships out of concrete (Roman or otherwise). The principle of displacement wasn't fully understood until Archimedes discovered it in the period between 287 and 212 BC, so it is unclear if ancient people would realize or recognize that a ship could be made out of materials other than wood, reeds or skin. Certainly the idea that something made of concrete would float would be counterintuitive to people living then (and indeed it is rather counter intuitive for many people today). The other issue, assuming someone has determined the principle of displacement and developed a means of casting a thin structure out of concrete, is how to assemble the structure. It is impractical to cast a single concrete structure of that size even today, so I would expect the ship to be made out of a large number of modules attached together something like an egg crate or ice tray: [![enter image description here](https://i.stack.imgur.com/fymir.jpg)](https://i.stack.imgur.com/fymir.jpg) Ice cube tray model of the ship Each module can be cast as an open topped cube, but the real difficulty comes in attaching each cube to the others in the ship's structure. Attachment points are going to be areas where stresses are concentrated (especially during rough weather) and could also be prone to leakage, meaning a large part of the crew's duties will be bailing out the ship, and constantly moving around and checking attachments, tightening or otherwise shorting them up and fixing packing, gaskets or other seals which are used to keep water out. For that level of technology, I would expect large bolts or lashings to be used to attach the pieces together. Another issue is that concrete is strong compressively but not in tension. If the pieces are rubbing against each other or get slammed against each other they can break. This is also an issue when considering how the ship is run. Wooden ships have carpenters aboard who can fix the ship when under weigh, but fixing a hole in a module of a concrete ship at sea will be challenging to say the least. So while this is a "possible" project, ultimately it is both improbable given the technological restraints of the day and impractical as a seagoing vessel. [Answer] The possibility of floating islands was well known to the Romans, and the Greeks before them. [Delos](https://en.wikipedia.org/wiki/Delos) is a little island that according to myth, floated around the Aegean until it agreed to risk the wrath of Hera and become the birthplace of the twin gods Apollo and Artemis. Poseidon anchored it in gratitude. It was a rich and fancy place for hundreds of years, despite a dearth of any natural resources. [![painting of Delos](https://i.stack.imgur.com/ZaChV.jpg)](https://i.stack.imgur.com/ZaChV.jpg) painting of Delos by Carl Anton Joseph Rottmann; from Wikipedia article > > Leto spoke winged words, asking her: "Delos, if you are willing to > be the home of my son, Phoebus Apollo, and to found a fat temple, > > no other will ever touch you nor forget you. I do not think you will > become fat in cattle and sheep, neither will you bear ripe fruits or > produce abundant plants. But if you have the temple of Apollo Far > Darter, all men will bring you hecatombs and gather here and the > insatiable savor of fat will always rise upwards. You will feed > those from another's hand those who inhabit you, since your soil is > not fat." Thus she spoke. > > > <https://msu.edu/~tyrrell/Apollo.htm> I propose your Romans do not build the island from scratch, but discover naturally occurring floating islands and then put them together and caulk over them with concrete. Giant rafts of pumice do float the ocean after volcanic events (even today) and maybe this is where the idea of floating islands came from. I am hoping for larger pieces. One needs pumice for roman concrete in any event! [![giant floating pumice raft](https://i.stack.imgur.com/LecIh.jpg)](https://i.stack.imgur.com/LecIh.jpg) giant raft of pumice from <http://volcano.oregonstate.edu/floating-pumice-%E2%80%93-oceanic-hazard> Patching up and reinforcing a natural floating pumice island would require much less concrete than building from scratch. I think that having the island be a center for ceremony and worship (as done on Delos) might work better than having it be a cumbersome, barely steerable ship. You could definitely have rainwater capture; looking thru images of Delos there is still an ancient cistern there. I am less optimistic about the possibility of defense. The Irish monks knew about the Vikings and had time to build and the Vikings still came and took all their stuff. That also happened to Delos, eventually and was the end of it. But if the keepers of your island knew the secret of Greek Fire... [Answer] A pontoon city. It is impossible as a single structure, roll and twist would rip a steel ship even a fraction of that size apart, a concrete one would not stand a chance. If you attached engines too it it would break apart so fast the paint wouldn't even have a chance to dry. It gets even worse if it is hollow. the larger a ship is the more flex it is subjected to. On the other hand, as a mass of linked but independent structure it might be possible. Thousands of independent floating blocks. because it is not rigid it can flex easily. NSBD's idea about pumice is not bad, small natural pumice rafts have existed. The best way to do it would be to cut many many giant cubes of pumice, drill a few holes through them to run rope and poles and you may have something viable. You do need to seal the pumice however, pumice does not float for long. The bigger they are the deeper they float the less waves will be able to bother them. The same thing could be accomplished with lighter than water concrete, the concrete will float a lot lower in the water as well but it will also cost a fortune to make and concrete like that may be beyond roman technology. the island's biggest problem is a complete lack of natural resources, they have to import everything, which costs money. Building this thing would bankrupt an empire and keeping it supplied would require it being one of the largest trading hubs in history, because they have nothing to work with. Remember they have import everything except food and maybe water, all the timber all the fuel all the metal all pottery, they have zero natural resources except fish meat, and possibly rain water and some high out put food crop if they are lucky. They cannot even manufacture replacements or repairs for their concrete without outside help. Lastly your island is not going to make a circuit it is going to end up in the north atlantic gyre where it is a huge pain to get ships to and from. No engine is going to be able to overcome the drag this structure will incur when moving against the currents. they would be better off anchoring it somewhere. [Answer] Don't plan it. [Find it.](https://en.wikipedia.org/wiki/Pumice_raft) Since pumice isn't very strong as parts weather the raft people make repairs using the best materials available. Over decades pumice patched to pumices wears out, but the cement they used to connect parts is still buoyant by trapping air where the pumice was. A much smaller (though still very large) all cement craft is the final product. [Answer] I'm going to Crib a little off of Thucydides as far as some of the modular aspects of construction and add a little something else that is possible to address some problems with cement sections banging into each other. [Pykrete](https://en.wikipedia.org/wiki/Pykrete) might be something that your ancient Roman types could use to help make this floating island possible. Here is how I see this working: They make a few concrete boats and go sailing to the far North. Of a period of a year, they learn about mixing wood shavings with water and freezing it to form a buoyant and very strong substance. They link the 2 ships with pykrete into a sort of oversized catamaran. This is successful, so they return to Rome and have family begin construction on more concrete boats. When they get back north, they decide think, why have family on a different boat, lets join the new boats to our catamaran, since that worked out. See where I am going here... The Pykrete will fill the gaps between the concrete boats and act as both a connective material as well as a collision buffer. Once it's frozen, the concrete boats are going to be protected from smacking each other. You could go on, building out year after year. Eventually get to the poiint that the oldest boats are there for structure and storage and build up. As your surface increases you might even be able to move some dirt on top of some of the structure for some basic agriculture. Maybe think about the hanging gardens of Babylon. What you are going to need, eventually, is some sort of propulsion so you can return to the north to re-freeze everything every so often. I don't know precisely how, maybe with massive sails on masts made from huge trees. Maybe with alchemy or some other handwavium. Sounds like an interesting premise Additional information on a planned WWII supercarrier from pycrekte is [available here](https://en.wikipedia.org/wiki/Project_Habakkuk) Big boats are possible when you realize that Ice is Nice! [Answer] This is a fascinating idea but sadly is not at all practical. Roman concrete is an interesting and surprisingly strong material, but it would not be suitable for constructing such a large ocean going vessel. No large structure could realistically be made out of Roman concrete, or any other form of concrete, unless it was steel reinforced. And even assuming the far superior tensile strength of reinforced concrete over unreinforced concrete, such a large structure would be very vulnerable to destruction in a storm due to heave and torsional strains. As severe storms are not uncommon in the Atlantic I doubt it would last long. Having a segmented structure would help in one way but would present other serious issues such as how to design joints that can move successfully with 6 degrees of freedom whilst retaining structural cohesion. [Answer] So I'm going to attack this problem at points 2,3, and 5 because the choice of building material isn’t the most problematic part. The biggest question is, how big will this thing have to be to support just one person? From there, we can scale. Let's figure out how big an island would have to be to support a single person. ## The island/ecology Now that we've got an estimate for how much we need to keep afloat, we can calculate the size of our 1-person island. Although other commenters have pointed out the need for compartmentalization and structural reinforcement, we're going for a minimum size, so I designed a spherical shell-like boat made of pozzolan. We're adding weight with this shell, but it's also displacing water- which is what we want. The general equation we're solving is $weight\ of\ shell + weight\ of\ soil = weight\ of\ water\ displaced$ ### Weight of shell Weight of the shell is complicated, but I assumed a 1m thick wall which simplifies the volume to $4\pi r^2t\\frac{1500kg}{m^3} \approx 9000\r^2kg$ This is the maximum buoyancy we can have- others have proposed modular systems and the like, but this was just a thought experiment to see what's theoretically possible. Anything modular or reinforced will quite possibly never float at all. ### Weight of soil The heaviest thing actually on the boat will definitely be the soil needed to farm. We can avoid the weight of the freshwater ponds by storing it in containers suspended over the side of the ship- that way they'll actually help a little with buoyancy. A person needs ~2000 calories per day. On a boat in the middle of the ocean, we have the advantage of being able to harvest seaweed- in this case, it'd be Sargassum. Not very tasty, but edible, and certainly enough of it. I'll say this knocks our calorie requirement down to ~1000 calories per day, because we need to get other nutrients that seaweed doesn't have. The two plants that come to mind are potatoes and nuts, which grow well together. Unfortunately, these plants weigh a lot because of the soil they require- potatoes require about 10 liters of soil and peanuts about 16. Given the calories in a potato, how many potatoes a plant produces a year, and the soil required by one plant, I end up with 7,000 liters of soil per person per year. For peanuts, by a similar calculation, I end up with 5,000 liters of soil per person per year. With a soil density of 1.5kg/L, that's 18,000kg of soil we need to support and keep afloat. At minimum. For one person. ### Calculations Now we can return to our original question- substituting the equation earlier with our new numbers becomes $9000r^2kg+18000kg=\frac{4}{3}\pi r^3\1000\frac{kg}{m^3}$ This solves nicely to output 1500m* as the radius for our spherical boat topped with soil. Here, I almost gave up on the question- there's no way a pre-modern society would be able to manufacture this, and it'd just be for one person. It does scale back with more people because the soil requirement grows linearly and the volume grows as the cube of the radius, but it's not going to get smaller. However, given that you're okay with a mile-long boat I'll push on. ## Ocean currents You say you've plotted a course that would allow you to float indefinitely in circles, and I'll admit I'm skeptical. I assume you're using the North Atlantic Gyre to circulate, but objects that are suspended in the gyre don't circulate nicely indefinitely- they're deflected into the middle of the gyre by the Coriolis force, which is why we have things like the Great Pacific Garbage Patch and the Sargasso Sea. Check out this video from the UCLA spin lab- it does a great job of explaining it: <https://www.youtube.com/watch?v=yP6eG9iXmKc>. However, we've got a boat- a rudder wouldn't work because we don't have a keel, but maybe some sails on the surface could solve that. They'd be only raised when a favorable wind is blowing away from the center of the gyre, and that might be enough to keep you out of it. The biggest problem with relying on ocean currents is that they are slow. It takes about 5 years for water to circulate around a gyre, and that'd be highly variable. This means that for time spans of multiple years at a time, you'd be in the middle of the ocean and essentially impossible to reach, let alone find. The Canary Current is especially slow- moving only 0.03 m/s means it could take you a couple years just to float from north to south. Even worse, this slow speed means you'd spend a year floating in freezing cold waters near the Arctic, then two years floating near the equator in the dreaded doldrums. That's why the biology would be vital- but your crops would die every time you moved north or south. Perhaps crop rotation could help? If you had two different strains of potatoes or nuts, you could swap them out as you got warmer or colder. ## TL;DR: I hope that gives you some perspective on the challenges you're facing. In essence, your floating island would have to be massive, you'd have to cultivate multiple types of crops and manage them perfectly, and you'd have to periodically avoid getting swept into the gyre. Trade would be nearly impossible- nobody will be able to find you, and as soon as a sailing ship leaves to trade with the mainland it'd be impossible to find the way back. Of course, that assumes everything goes perfectly- but a lot of the other answers in this chain deal with problems like patching the ship or storms. However, those kind of problems are often the ideal focus points for stories such as yours. Good luck! [Answer] I will focus only on the actual building material and 2 examples on how it may come about. The romans were fairly good at working iron. If your willing to handwave a mile long concrete ship, how about some electricity? Biorock is stronger then your average concrete and it is grown through seawater mineral accumulation. Basically have a few volts at a low DC current going through normal iron electrodes. The process reverses rust and is self repairing so long as you have current. So if they made steel mesh and generated a small amount of electricity then they could have a self repairing fairly strong biorock vessel. The accidental discovery of electricity could be as simple lodestone. Some kid was playing with lodestone near a wind mill with a copper bearing and noticed the lodestone was attracted to the rotating copper bearing. From there it should be pretty straightforward for them to make some basic homopolar motors. Or perhaps an alchemist doing their experiments accidentally invents the voltaic pile. ]
[Question] [ Suppose the Wicked Witch of the West was simply an alien life form that was stranded in Oz. She comes from a race of beings that are water soluble. She would have to be able to resist a small amount of water, or else any contact with water vapors in the atmosphere would dissolve her. Yet, any significant amount of water (such as a cup of it), would instantly cause her to dissolve. Is this even possible? [Answer] Certainly, this is possible. Almost all things are, after all. However, the effect of melting when exposed to large amounts of liquid water is probably not what it initially appears to be. An alien organism that is tolerant to small amounts of water is probably one that is tolerant to larger amounts too, so why would a large amount of water make the alien melt? My hypothesis is that this particular alien is actually composed of a great many small subunits. This is similar to our cellular model, but the alien subunits may themselves be tiny, aquatic, multicellular organisms. These organisms have the ability to clump together into a single colony in times of drought in order to present a reduced surface area through which water may be lost, and when a sufficiently heavy rain comes along, they can disband and do their own thing, such as mating. Over time, these organisms have evolved the ability to move and form a group intelligence while joined in a colony, however the single consciousness which results is dependent upon the particular arrangement of the individual organisms, and should the colony disband, its consciousness will cease, and even if the colony subsequently reforms from the same organisms, the inability of the organisms to achieve exactly the same configuration as before means that the reformed colony will be a new consciousness with a different personality, though with remnant skills and knowledge left over from the previous configuration. Naturally, the longer a colony exists in a particular configuration, the more skills and knowledge it will accumulate, increasing the survivability of the colony. This would lead to a state where the collective consciousnesses of the colonies would be reluctant to disband voluntarily unless presented with a suitably large body of water, but where a relatively small amount of water could fool the individual organisms into disbanding. Of course, if there really wasn't enough water, the colony could reform - as a different consciousness - but this would be a case where sentience has overtaken the limitations of evolution. Yes, the colony could reform - doing so would be better than not doing so if there really isn't enough water - but the reformed colony would no longer be the same person since its neural pathways would be different. So, if the Wicked Witch of the West was such a colonial organism, splashing it with sufficient water to trigger the instinctual disbanding of the colony in preparation for the mating season would in effect be a sentence of death for that particular colonial sentience, even if after a little while the colonial organisms could re-form the colony. After such an event, despite all the same organisms being present, it would be a different colony with a different personality and probably fewer skills. Given that, it is not surprising that the consciousness of the "melting" Wicked Witch could - in the moments remaining to it - recognise that it would cease to exist due to the triggering of an instinctive response of its member organisms, and bewail that fact. It would have good cause, since any reformed colony would likely have fewer valuable skills, and hence be less able to survive. EDIT In response to the OP's comment that it might be possible to re-imprint the colony's original personality onto the reformed colony, I offer this variation, which would not be too difficult to evolve: The colonial subunits have individual identities, and after spending a considerable amount of time next to other individuals, can remember exactly which individuals to whom they were adjacent, even after dissolution and reformation of the colony. While the colony could be reformed quite quickly, it would have a random configuration with a new personality and few skills. However, the individual subunits memories of their previous neighbours and the neural network of the colony would allow the subunits to change their positions within the colony to recreate its previous configuration and thus restore the previous personality with its more developed skills. However, if we are using the Wizard of Oz as the template for this species, then the behaviour above is not consistent with the reactions of the Wicked Witch of the West to being splashed by a bucketful of water: From Frank L Baum's novel, The Wonderful Wizard of Oz: > > "You are a wicked creature!" cried Dorothy. "You have no right to > take my shoe from me." > > > "I shall keep it, just the same," said the Witch, laughing at her, > "and some day I shall get the other one from you, too." > > > This made Dorothy so very angry that she picked up the bucket of > water that stood near and dashed it over the Witch, wetting her from > head to foot. > > > Instantly the wicked woman gave a loud cry of fear; and then, as > Dorothy looked at her in wonder, the Witch began to shrink and fall > away. > > > "See what you have done!" she screamed. "In a minute I shall melt > away." > > > "I'm very sorry, indeed," said Dorothy, who was truly frightened to > see the Witch actually melting away like brown sugar before her very > eyes. > > > "Didn't you know water would be the end of me?" asked the Witch, in a > wailing, despairing voice. > > > "Of course not," answered Dorothy; "how should I?" > > > "Well, in a few minutes I shall be all melted, and you will have the > castle to yourself. I have been wicked in my day, but I never thought > a little girl like you would ever be able to melt me and end my > wicked deeds. Look out--here I go!" > > > or from the The Wizard of Oz movie script: > > MS -- Dorothy throwing water at Scarecrow -- some of it hits the Witch in > the face -- Tin Man standing at left with the Lion -- > > > > ``` > SCARECROW > Help! > > ``` > > MCU -- The water hits the Witch in the face -- > > > MS -- The Witch screams as the water hits her -- Tin Man, Lion, Dorothy > and Scarecrow look at her -- > > > MLS -- The Lion, Tin Man, Dorothy and Scarecrow watch the Witch as she > screams and melts away -- camera shooting past Winkies in the f.g. -- the > Witch curses as she disappears, finally only her cloak and hat remain on > the floor -- her voice fades away -- > > > > ``` > WITCH > Ohhh -- you cursed brat! Look what you've > done! I'm melting! Melting! Oh -- what a > world -- what a world! Who would have > thought a good little girl like you could > destroy my beautiful wickedness!? Ohhh! > Look out! Look out! I'm going. Ohhhh! > Ohhhhhh.... > > ``` > > Such behaviour would be more consistent with the behaviour I originally described, in that the colonial subunits are not capable of restoring a particular configuration through the process of dissolution and reformation of the colony. However, the novel also describes the Wicked Witch of the West as being "cunning", so it is not beyond the bounds of possibility that this reaction may have been a sham intended to lead Dorothy and company to believe that this dissolution was fatal, so that when the colony reformed - hopefully after Dorothy and company had left the area - it could restore its long-term configuration and personality and continue pursuing its goals with the added advantage that its enemies believed it to be deceased. [Answer] One way this is possible is to have an organism that uses methanol as a solvent. Methanol is less polar than water, so water would act like an acid, hydrolyzing many of the creature's constituent molecules. As far as resisting humidity, that becomes a bit more difficult. One explanation that may work is that it has some kind of "Crust" at the surface of the skin. This could be made of all sorts of stuff, but if it were to be made of olivine ((Mg, Fe)2SiO4) it would give her skin a green color! Hope this helps. ]
[Question] [ I have seen a few similar questions but none seem to take the density of a planet into account. I'm creating a planet on which several small civilisations develop. The planet needs to have a few biomes of varying temperature such as mountain ranges, deserts, temperate areas etc. What is the smallest this planet can be? Also taking into account that this planet may be many times the density of Earth. For instance a planet half the volume but of double the mass would have the same gravitational pull (correct me here if I'm wrong). Would this higher density cause any problems as well? [Answer] The answer to this question is actually quite complicated or rather it depends very much upon the parameters that you plug into the equations. I'll tell you the values that I used to get my answer and you can tweak those as you desire to explore the situation further. ### Assumptions 1. I define habitable (from a gas retention perspective) as being able to retain 50% of its gaseous water for 4 billion years $\lambda\_{water} = 4 \cdot 10^9 years$. 2. I define habitable, from a temperature perspective, as being no colder than $0 C = 273 K$ 3. Density of the $\rho\_{planet} \approx \rho\_{iron} = 8 \frac{g}{cm^3}$ 4. We'll assume that the "stuff of life" very thinly overlays the basically iron planet. ### Jim2B Planet I have a complicated and custom spreadsheet that is composed of both the physics and some empirical handwaving to calculate gas retention. When I run the figures through the spreadsheet, I find that a planet with the following properties meets my minimum specs for habitability: * $M\_{min} = 2 \cdot 10^{24} kg$ (3.3x of Mars' mass or 1/3 of the Earth's mass) * $r\_{min} = 3,900 km$ (120% of Mars' radius) * $\rho\_{min} = 8 \frac{g}{cm^3}$ * $G\_{surface} = 0.89 g$ (~Venus' surface gravity) * $V\_{esc} = 8,263 \frac{km}{s}$ (about 74% of Earth's escape velocity) * $T\_{surface} = 273 K$ (average surface temperature about the freezing point of water) ### ckersch Planet Using the same process as above but changing the habitability requirements a little. Now I assume that water retention isn't the issue because we have very deep oceans and plenty of water so if we lose more than 1/2, it's no problem. Now we just need to hold onto 50% of our $O\_2$ for $4 \cdot 10^9$ years. * $M\_{min} = 8.5 \cdot 10^{23} kg$ (130% of Mars' mass or 1/7 of the Earth's mass) * $r\_{min} = 2,900 km$ (85% of Mars' radius - 120% of Mercury's radius) * $\rho\_{min} = 8 \frac{g}{cm^3}$ * $G\_{surface} = 0.67 g$ (~2x Mars' surface gravity) * $V\_{esc} = 6,200 \frac{km}{s}$ (about 55% of Earth's escape velocity) * $T\_{surface} = 273 K$ (average surface temperature about the freezing point of water) [Answer] First, your maths is wrong. A planet with half the volume of Earth and double the mass would be four times as dense, and would have a much stronger surface gravity. Second, you need to think about geochemistry. What is your dense planet made of? There are few plausible substances that will give you a noticeably higher density than the Earth -- we know of a bunch of planets (the gas giants) that are much less dense, but none that are denser. [Answer] Higher density has problems because it means the planet will have a bizarre composition. Bizarre in the sense that it will be composed of improbable ratios of elements. Solid osmium planets, indeed! Not impossible, but their probability of their existence is almost laughable. OK, let's say one in 10^22 possible planets. Let's face it osmium is rare. A higher atomic number which means nucleosynthesis and supernovas don't make that much of the stuff. Besides the geochemistry of an osmium planet would be the stuff of nightmares. [![enter image description here](https://i.stack.imgur.com/Bjebk.jpg)](https://i.stack.imgur.com/Bjebk.jpg) Diamond planets are more feasible because carbon is a common element. The question is what and how the pressure applied to compress the mass of a whole carbon planet? While there have been studies suggesting gigantic diamonds forming at the centre of gas giant planets and you can imagine the gas giant outer layers have evaporated away. Say when its primary star turned red giant. Be warned diamond has a tendency to decompress explosively. Interesting that, an entire planet blowing up in one big explosion. Diamond planets aren't forever. Space-going James Bonds beware. [![enter image description here](https://i.stack.imgur.com/YSYcN.jpg)](https://i.stack.imgur.com/YSYcN.jpg) Stephen Dole's Habitable Planets for Man (2nd edition, 1970) estimated the smallest habitable planet would be, In Earth units, mass 0,40, radius 0.78 or 3090 miles, and surface gravity of 0.68. This assumes density of material similar to that of the Earth. This provides a baseline habitability. If you use the surface gravity as a lower bound, you jiggle around with density and the planet's radius to shrink or expand to your heart's content. As for higher densities that demands exotic planetary compositions, you can count me out on this score. I agree with Luis Hendriques' comment. If you want higher density planets don't try and explain it. We can all play let's pretend and leave it at that. [Answer] Some very dense metals your planet could possibly be made of, Platinum - Density 21.4 Iridium - Density 22.4 Osmium - Density 22.6 These metals have a very high density all above >20 but aren't very common, also the planet needs a magnetic field to deflect the solar wind. Mercury is the same age as Mars and Venus but possess a magnetic field unlike Mars And Venus, Planet Mercury has a density about 5.4 and has maintained a magnetic field for billions of years but it is no longer tectonically active. This created planet won't have plate tectonics unless it's a Moon of a large gas giant. An example of a pure Iridium planet Mass- 0.065 Earth, Gravity 1 G, Radius 3160 km, Density 22.4 Now it seems extremly unlikely it can be ALL Iridium since the mantle needs to be partially silicate materials. Now let's see we need some Iron and Nickle for a magnetic field, Perhaps a massive core of Iron and Nickle with an outer core of Osmium and Iridium mix in sone Platinum too. Now for the mixed planet of Iron, Nickle, Iridium, Osmium And Platinum + a thin silicate mantle we get Mass - 0.11 Earth, Gravity 1 G, Radius 4240 km, 0.33 Earth radius, with a density of 16.5. Now even this seems somewhat unlikely but still possible [Answer] A planet with a magnetic field needs an iron-nickel core. Density of iron is 7.87; density of nickel is just a bit higher, at 8.91. So your best guess would be to have a planet with a gigantic iron-nickel core, and a high percent of nickel in that core (is that possible?). Let's suppose that the whole planed has a density like that of iron: 7.87. With that density, it could have a radius of 4,000 km - roughly 2/3 of the Earth, with a 4/9 surface and a 8/27 volume with a superficial gravity of 0.9 g. I am not sure that surface temperature, due to the narrow crust and mantle, would be livable, though. --- The above would be an attempt to answer the question - smallest possibly habitable planet. For your suggestion of "a planet with half the volume of Earth", its radius would be 6,378km (Earth's radius) X 0.79370052598 (cubic root of 1/2) = 5,062km. It would require much less increase in density: at 6.9 density, it would have a 1g surface gravity. It would need a bigger iron-nickel core, but not incredibly bigger. And even with the exact density of Earth, it would have a 0.8g surface gravity, which would perhaps hold an oxygen-nitrogen atmosphere long enough for life to evolve. Of course, those are "hard-science" answers. You could have a smaller planet with pseudo-scientific explanations; I have suggested some in a comment to Cursed1701's answer, and here is one more, that seems perhaps more plausible, or at least more scientific-sounding, than those: G - the universal gravitational constant - is indeed not constant, much less universal, and in the case of your planet, it is higher than it is at Earth. --- Here is a nice [Gravity Calculator for Astronomical Bodies Based on Radius and Density](http://www.ericjamesstone.com/blog/home/gravity-calculator-for-astronomical-bodies-based-on-radius-and-density/). Have fun with it! [Answer] well, to make it denser you would need a mantle of a denser material, say osmium iron has a density of [7.87 tonnes per cubic metre](http://www.convert-me.com/en/convert/density/densiron.html) and osmium has a density of [22.5 tonnes per cubic metre](http://hypertextbook.com/facts/2007/KarmenHo.shtml), which would help keep your planet smaller if it were to have the same mass as the earth. but, I have no idea what that would do to the tectonics, and if they could form, and you need tectonics to have oceans and mountains and a lot of different biomes. [Answer] I disagree with some of the information in some of the previous answers. Especially these two: "We know of a bunch of planets (the gas giants) that are much less dense, but none that are denser." and "A planet with a magnetic field needs an iron-nickel core. " KELT-1b is estimated to be 4 to 5 times more dense(23.7 g/cm3) than Earth(5.51 g/cm³) and Jupiter has a MASSIVE magnetic field and the most commonly accepted explanation is due to metallic hydrogen, not nickel/iron, in Jupiter's core. Someone in the comments also mentioned that natural processes could not create denser materials, and another comment mentioned that compaction due to gravity would be reversed once enough mass was removed to reduce the gravity, but I see no evidence to suggest that either of things are true. Fusion in stars can create metals up to the density of Iron, but Earth already has much more dense material than that, created by the earth itself, or on some other planet and later delivered here by collision. I'm fairly certain that gold or Osmium don't dissipate when removed from Earth's gravity well, so there could very well be other materials, even more dense, created in other cosmic planetary bodies, in whole or in part, that would remain stable after being separated from the gravity/pressure where they were originally created. Having said all that, I can't provide a direct number or calculation for what might be the minimum size (radius/circumference/etc.), though I suspect the calculations in the answer selected by the OP are 'close enough'. So, here are my two cents on the topic: Assuming some unlikely, though certainly possible (at least within current scientific understanding), occurrences, I would accept the possibility of a planet easily composed of material that would provide a density at least 3 times that of Earth, while at the same time having a small enough radius to give it near-earth-like gravity (plug in those numbers, or anything roughly similar, in to the calculations of the accepted answer, and viola), while maintaining atmosphere and magnetosphere, and other necessities of humanoid life. Then, given the sheer number of galaxies we've discovered, and the sheer number of stars in them, and the sheer number of planets orbiting (and some not orbiting any of) those stars, and the laws of probability, those 'unlikely occurrences' could very well have happened somewhere in our known universe. [Answer] > > For instance a planet half the volume but of double the mass would have the same gravitational pull (correct me here if I'm wrong). > > > You're wrong. :) (Hey, you asked us to tell you!) To expand upon this, some formulas. Density $$\rho = \frac{m}{V}$$ Volume of a sphere $$V = \frac{4}{3}\pi r^3$$ Acceleration due to gravity $$g = \frac{Gm}{r^2}$$ r: the radius of the planet. G: the universal gravitation constant, $6.67 \* 10^-11 \frac{Nm^2}{kg^2}$. m: the mass of the planet. g: the acceleration due to gravity. V: the volume of the planet. $\rho$: density. Using these formulas, you can determine that half the volume and double the mass would be around 25% more gravity. The relation that you want is that mass and the square of the radius balance each other. If you doubled the mass, to hold the acceleration due to gravity constant, you would have to take $\sqrt{2}$ of the radius. So about 141% of the radius. More simply, if you halve the radius, you need only a quarter of the mass. That's an eighth of the volume or twice the density. ]
[Question] [ In story after sci-fi story you have images of clones stepping out of some sort of gooey bathtub or cloudy coffin type device. Be they a single doppelganger or whole clone armies. --- MY SETTING I am interested in all cloning scenarios as they may influence what I incorporate and how my story can be edited. Currently my scenario is a Interstellar Hospital Ship. Designed to get to planets/space-stations during emergencies that are not equipped for large disasters/conflict etc. It would settle into orbit around planet or dock with space-station and provide medical relief. It would be designed to deal with large numbers and varieties of patients and medical issues. Most patients would be treated with 'normal' technology and returned back to their wherever they came from, Some would undergo lengthy procedures onboard and some would be shipped back to more centralised systems and undergo whatever lengthy medical procedure is needed that the ship can't deal with. But in some cases this wouldn't be feasable. This is where cloning and a combination of other tech would come into play. For whatever reason death is imminent and the individual/s are necessary for the survival of the colony/station etc and they can't wait for travel back to the central systems or longer medical techniques on-board the ship. Cloning would be a last resort solution. Numbers for cloning can range from a single individual to the entire colony. There could be renegade situations where the cloning tech is used to create a clone army! You know human nature; anything for an edge in conflict! --- Consensus seems that you can't clone a person's brain as the neurons and brain chemistry etc goes down to the quantum physics scale. At best you would get a 'fuzzy copy'. Right now that is not the issue. Clarifiction: I don't need the clone to have any knowledge, memories or skills at the moment. Just a fully functioning body. Consensus also seems to be that you can alter a person's DNA (we do it even today with genome therapy, though on a very small scale) but any changes would only be seen in future descendents. --- MY QUESTION: How would your sufficiently advanced human/alien/other-worldly scientist grow a clone in a short timeframe of a day or so? Taking into account energy requirements, and materials needed to make a healthy copy of your subject (we are essentially a very big and complex sandcastle of different minerals and stardust)? 1. Would you have a batch of pre-manufactured body blanks that could be 'dressed' with the genetic code of a subject? Give them some sort of energy boost to activate the DNA into action. IMAGINE a larder full of blanks (at varying age development) hanging on conveyor belt like system. 2. Would you have to start from petri dish level and watch them develop though embryo, foetus, child, toddler, to the age of your subject in some sort of suspended animation sort device? (as Jay pointed out, this could be some sort of enhanced growth machine of your cloned material) IMAGINE a room full of containers with lots of goo, with clones in varying age development 3. As Ghotir Suggested, you simply, print the clone using a very advanced 3D printer. IMAGINE pretty much just watch 'The Fifth Element' cloning scene and ignore the dated graphics. --- Which clone is more likely to be able to 'get up and go'? Would you have to incorporate some sort of muscle strengthening/conditioning so they don't just collapse on the floor the moment they step out of their gooey bath/cloudy coffin shaped birthing chamber! --- Note. I'm using the reality check tag to get some perspective on how totally insane a science fiction process can be while still sounding plausible to my ever-suffering, only mildly-bewildered reader! I'm also assuming this would have to take place some time in the far future. At least a couple hundred to thousand years. EDITED to include some suggestions/reminders/clarifications from the comments and answers so far. Also included my story setting. [Answer] > > How would your sufficiently advanced human/alien/other-worldy scientist grow a clone in a short timeframe of a day or so? > > > Start with the absolutely realistic concept of [organ printing](https://en.wikipedia.org/wiki/Organ_printing), make it a far more mature technology, and scale it up from an organ to a body. Given what we can do now, I believe this is absolutely possible for a reasonable advance in technology. Note that this does not address how to handle the consciousness or knowledge - I think that's a far harder problem to solve. [Answer] Science fiction clones often bear little resemblance to real-life cloning. In real life, "cloning" means taking a cell from some living creature, and then inducing that cell to fission and reproduce, growing it through all the stages in and out of the womb -- embryo, fetus, new-born baby, child, adolescent, and finally adult. I've seen plenty of sci fi movies where someone steps into the "cloning chamber" and ten minutes later a full-grown adult walks out. That's just not how cloning works. A clone has to go through all the stages of growth that an "ordinary" person does. One could, of course, speculate on having a technology to make a person (or whatever creature, but I assume we're primarily talking about people here) grow faster, to develop from an embryo to an adult in weeks or hours instead of 20 years. That would be a totally separate technology from cloning, though presumably if it was invented it could be applied to clones. Exactly how it would work raises all sorts of questions. Even if you could somehow accelerate physical development, this person would then have no education or experience. It's hard to imagine how the result would be a functioning adult. You could speculate then on yet another technology, some feed into the brain that would give a person a lifetime of education and some equivalent of experience in a few hours. I suppose you could imagine copying a living person's memories to the "quick" person, or maybe a lifetime of fake memories could be synthesized by technicians and fed into this person. Anything like this is way beyond our current science and technology, but if you're writing a sci fi story, you can suppose whatever technology you need, right? When you take the cell from the original subject, you could theoreteically modify the DNA in that cell before starting it fissioning. Then every cell in the clone's body would have the altered DNA. The idea of having "blanks" that you would "imprint" ... somehow you'd have to modify the DNA in every cell. As there are something like 100 trillion cells in a human body, that would be a daunting task. There's no natural mechanism to multiply genetic changes throughout the body -- if there was, anything that damaged a cell, hazardous chemicals, sunburn, etc -- would quickly kill you. Maybe you could invent some process that would carry the genetic change from cell to cell, nanobots or something. That seems a whole lot harder than altering one cell before you start the whole process. There are still huge problems with cloning a mammal. The famous sheep clone Dolly began aging prematurely and died after 6 years, about half the normal lifespan of a sheep. Dolly was basically born already middle-aged. I presume this relates to telomeres -- mammal cells can only fission a limited number of times -- but I haven't studied the issue further. It's quite possible that if and when this problem is solved, there will be other obstacles. Producing a truly successful mammal clone is still several breakthrus away. A 10-minute clone is the technological equivalent of warp drive or time travel: you can certainly write a science fiction story about it, but nobody today has the vaguest idea of how you would actually do it. [Answer] Growing a human from a single egg is limited by the speed of biochemical reactions, supply of nutrients, and the need for chemical gradients to "tell" the body when and where to grow. If you had all the nutrients laid out with pre-existing chemical gradients you may be able to implant dozens/hundreds of pluripotent stem cells along this "blank" and have everything begin growing at once. So the bones form alongside the muscles and the internal organs. This way you wouldn't be limited by the need to have the circulatory system grow to supply nutrients and remove wastes or the placenta analogue to do the same. Currently our rate of growth is limited by these restrictions. Human cells typically take 12-24 hours to divide, but other species can be much faster. You will probably have a real problem with tumors as all this fast growing will have to be switched on and off with extreme precision, if a cell fails to respond appropriately it could lead to a tumor or the failure of an organ to properly develop. About the only way to build a body really quickly is to assemble one from pre-grown parts and grafts. Of course it will still need time for all the connections to heal, blood vessels to bridge gaps, and for nerve endings and lymphatics to grow down to the terminal endings. There are other considerations. Our immune system, for example, is "trained" in how to recognize self versus not-self, as well as lots of environmental pathogens. We also have lots of colonizing organisms on our skin and in our gut (and probably elsewhere) that will have to be seeded as well, lest the clone get a fatal infection within hours of "birth". Neuromuscular control is also learned as we grow, neurons are mapped out in our youth. Replicating this artificially would be a significant challenge if you want your clone to pop out ready to fight. If all you wanted was short lifespan soldiers you probably don't need DNA at all. It would basically be like going through chemotherapy (high replicating areas would suffer first) but if you were dropping these guys in for just one or two battles you would be ok. Maybe just the sensitive areas are cloned from DNA, things like bone marrow, the gut, and the skin. The rest could be stock "blanks" made of generic tissue that can't replicate itself. This would reduce the "grow" time of a clone. Severely edited DNA sequences (just what each cell line needs to function) may speed up replication as well, but then the cells could be very sensitive to radiation or drugs/toxins that interfere with DNA since every sequence is important (unlike our DNA, which is filled with junk sequences). [Answer] Dont grow them. 3D print them with nanobots. Nanobots are smaller then cells. They can build individual amino acids from raw materials. If a natural cell can do it then nanobots can do it faster and more efficiently. Forget the genetics. That doesnt matter to a nanobot molecular 3D printer. what matters are voxels. 3D pixels. Each cubic nanometer of the organism has a list of chemicals, the geometry, the electric charge, etc. That information is stored as a list of voxels, left to right, top to bottom, etc. With a chunk of biomass you could create exact replicas in a few hours. Note that molecular 3D printers are really good at organic chemistry because organic chemistry happens around room temperature. Its not a one size fits all solution. Steel for instance is better the way we do it now then using nanobots. But when we finally make the buggers, organic chemistry is well within their capabilities. ]
[Question] [ Let's go back 10,000-12,000 years, when humans have yet to make strides in basic machines. In our world, the invention of the wheel makes things easy to move, starting a transportation revolution. This will eventually lead to new technologies, and eventually the rise of more complicated machines. What if the wheel was never invented? In this world, humans discover a gel-like substance that, when put on an object, immediately reduces friction. All of a sudden, pushing a boulder across a grassy field is more like pushing a boulder across an icy pond - but even easier. The effects of friction can be almost totally neglected. This leads to a different type of transportation revolution. All of a sudden, the coolest new way to get around is in large sleds with their undersides coated with this gel. Soon, horses are domesticated - way ahead of schedule - as it becomes clear that putting them side by side in front of a sled is a great way to pull heavy loads. Will this society ever be motivated to invent the wheel (assuming that pulleys are created not out of axles, but out of gel-coated blocks)? Related points can be found in [In a society of flying beings, would the wheel ever be invented?](https://worldbuilding.stackexchange.com/questions/780/in-a-society-of-flying-beings-would-the-wheel-ever-be-invented), especially related to pulleys and the application of the wheel to transportation. [Answer] Historically, there have been many societies that never invented the wheel. We really only got rolling with wheels in the bronze age, and not everyone had them. For example, there's no evidence that the natives of Central America ever used wheels for anything beyond small children's toys. Where they were invented, they actually came after "more advanced" technologies like sailing ships. So your premise is sound: the wheel is not a primary invention. However, I find it unlikely that a society could become industrialized without adopting the wheel. It has many uses where low-friction linear motion just won't do: flywheels, electric motors and generators, millstones(where you need high friction), gearing in all sorts of mechanical things (clocks being the obvious example, but pretty much any technology you'd associate with steam-era industrial society relies on the existence of a wheel in one way or another), etc etc. Having a substance to dramatically reduce friction in a robust variety of circumstances like you describe would certainly change a lot about how technology evolves in that culture, but that substance can't replace wheels in every instance where we use them now. And even if it could, how abundant is it? The economics of "gel mining" might push someone to start using wheels for transportation as a more cost-efficient alternative. [Answer] The wheel will always be discovered given sufficient time and chance. Nature does not abhor a wheel. [Natural wheels exist in a variety of forms.](https://simple.wikipedia.org/wiki/Rolling_and_wheels_in_the_natural_world) Dung beetles form their meal into a ball and roll it around. Trees form logs that tend to roll down hills on occasion. Eyes are balls that rotate in a sockets. Knees are obvious ball and socket joints. Someone is going to forget to apply the sliding gel and when they attempt to push a log, the log will respond by rolling. Sure, people are often blind to the obvious. But even the Aztecs had wheels, they simply did not see the need to apply them in their society. Had they become more industrialized, I have no doubt that they would have been using wheels in more than toys. --- On soft soils and irregular terrains wheels are not ideal. Maybe that is partially the reason the Aztecs never made use of the wheel. But given their constructions, one wonders why they never invented the wheelbarrow. The Aztecs even made roads and bridges but not wagons. But the fact is that the wheelbarrow was apparently not known in Europe until about 1200 AD. This just seems incredible to me. Romans had chariot races in the Coliseum, but no wheelbarrows to help in its construction. So just because something seems incredibly obvious in hindsight, it does not mean that it is actually obvious. Still, given enough time and potential observers looking for possible applications of a technology, someone will see the blindingly obvious for what it really is. By the time you've added physicists and mathematicians to society, [the use of a sphere is self-evident.](https://en.wikipedia.org/wiki/Spherical_cow) [Answer] ## Yes --- The [Aztec](http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=aa12) Empire lasted for around 1000 years and their largest city was larger then any European city at the time, and they [never](http://www.zoesaadia.com/real-smart-folks-but-no-wheel/) discovered the wheel. In fact, [no New World](http://www.straightdope.com/columns/read/223/why-did-the-peoples-of-the-new-world-fail-to-invent-the-wheel) culture invented the wheel before meeting an eastern power. We don't know [why](http://www.scientificamerican.com/article/why-it-took-so-long-to-inv/) they didn't invent the wheel for themselves, but they didn't so it is possible. My suggestion for a culture without a wheel is simply to have their environment be too difficult for the use of wheels, like a jungle, swamp or mountain. [Answer] The wheel and rotational motion are almost impossible to separate. If you develop rotational motion, you'll almost certainly end up developing a wheel by accident (or a pulley or whatnot). Now if there was a very easy way to minimize friction for transportation purposes, we may never decide to use the shape of a wheel for transportation, but we'll certainly invent the idea that circular things work better for rotation. [Answer] The Inca had llamas that carried burdens,and sometimes pulled a narrow sled, but the roads were not accommodating for a wheeled cart. ]
[Question] [ If we take an earth-sized planet with similar atmosphere, and put it into a P-type binary orbit, could it sustain human life? For sake of clarity, assume both stars are G-type stars and the planet is orbiting at 1-2 AUs from the stars. [Answer] It’s plausible. [Research indicates that low mass binary stars may be especially suited to supporting life.](https://www.scientificamerican.com/article/extraterrestrial-life-may/) Granted, this article discusses stars of a lower mass than G-type stars, and planets orbiting at greater AU, but this is a promising sign.[Real research in astrophysics is being done to determine the habitability zones of binary star systems](https://www.frontiersin.org/articles/10.3389/fspas.2021.640830/full) Given that this is an ongoing topic of research, and one that is fairly young, it is reasonable to have a binary star system posses the right features for supporting life. [Answer] As told [here](https://en.wikipedia.org/wiki/Habitability_of_binary_star_systems) it is possible for S-Type and P-Type planets to be in habitable zone.. Studies of Alpha Centauri show that Centauri A and B have an 11 au distance at closest approach (23 au mean), and both have stable habitable zones for non-circumbinary (S-Type) planets. Kepler-47c is a gas giant in the circumbinary (P-Type) habitable zone of the Kepler-47 system. If Earth-like planets form in or migrate into the circumbinary (P-Type) habitable zone, they would be capable of sustaining liquid water on their surface in spite of the dynamical and radiative interaction with the binary stars. For more details, read [here](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5384241/) and [here](https://www.davincisciencecenter.org/wp-content/uploads/2020/06/Madison-Salter.pdf). ]
[Question] [ Bob loves plants. More specifically, he loves [terrariums](https://en.wikipedia.org/wiki/Terrarium). Bob's magnum opus is a large terrarium made from a 5-gallon glass water jug. Inside is a miniature ecosystem: plants grow, detritivores feed on the fallen leaves, larger insects hunt them down, and anything that dies has its constituent nutrients recycled to propagate more life. Nothing enters or leaves the jug, not even air. For our intents and purposes it is the perfect self-sustaining terrarium. One day Bob wakes up and learns that nuclear war will come in exactly 24 hours. Let's handwave how or why: all that matters is that the 100 most populated US cities will be hit with 10 nukes each, including his home in San Francisco. Bob is scared for his life. But more importantly, Bob is scared for his terrarium. He mustn't let it die, no matter what. Lets say Bob has a million dollars to spend and the determination to do whatever it takes to keep his plants alive for at least 1 year. As stated the ecosystem is self-sustaining, but even it has some needs. Bob will have to: * establish a light source- natural sunlight from a window is a possibility, but he cannot rely on that during a nuclear winter. The ideal alternative is a typical warm white light bulb, which will require power lasting at least the whole year. * Keep it safe from radiation- I couldn't find much on how much radiation glass or plants can take, so let's just say to keep it as far away from major cities as possible while still fulfilling the first requirement. Given the above, and that Bob cannot leave the United States for any reason: what is the best thing Bob can do to make sure his terrarium survives a nuclear war? It does not matter whether he lives or dies. [Answer] This might be a boring answer, but the terrarium doesn't make a huge difference. Bob should do what anyone else who had $1 million and knew about an upcoming nuclear war should do. Bob should spend \$800k on non perishable food, medical supplies, gasoline, a geiger counter, and a grow light with a bunch of spare bulbs, then move to a rural community; use the remaining $200k on a house with a decent basement, and a generator. Bob should make good friends with his neighbors, working together is best for everyone. If his community is healthy and safe, he should be able to take care of his terrarium in his free time. [Answer] Buy a 50 W LED grow light. Buy about two tons of lithium batteries (assuming 200 W\*h/kg). Charge them. Buy or rent a large bank vault -- 12" to 18" thick walls are standard, and will stop pretty much any radiation if they stay intact. Choose one in a location that's unlikely to get a direct hit, and hope you don't have an earthquake within the year. Put the batteries, LED, and carboy in the vault. Lock the door. Come back in a year. [Answer] The small town approach won't work--your small town is going to get overrun by the survivors from the cities looking for food. The basic approach is right, though--but you're looking for a 4x4 HCV, not a house. Head into the most remote location you can reach, something without too good visibility so people don't see your vehicle. [Answer] Of course Bob's plants can survive, in any built world. If Bob cared about natural sunlight being unreliable, why would you not let him use a generator for that typical warm, white light bulb? If he cared about radiation, why would you not let him use radiation-resistant glass? ]
[Question] [ There is a humanoid species whose natural lifespan/period of senescence is very short compared to other sapients of the setting(around 20 years). They have similar levels of intelligence to humans and have sapience but due to them only living long enough to reach adulthood and reproduce but not long enough to properly raise and educate their offspring most members are either civilized and relatively educated orphans in the cities or savage and/or feral groups in the wild. Despite their short lifespan being widely known about there are nonetheless individuals of the species who seem to live far longer than is normal for their kind, even longer than humans in some cases. The secret behind these extended lifespans are not discussed or well known about even among their own kind but to summarize it all boils down to raw(uncooked) cannibalism. They can eat members of their own kind to extend their own lives, the amount of time gained depending on the mass they consume to a maximum of three years per adult eaten(bones and marrow excluded). While the setting is planned to have some sort of magic I want most things to exist as independently from magic as possible. Are there any natural biological mechanisms that would allow an organism to extend their lifespans via cannibalism? [Answer] How about an inverted/slightly altered version of Kuru disease? Kuru disease is a transmissible spongiform encephalopathy (TSE), which is famous for being transmissable and becoming deadly due to cannibalism (Wiki here: [1](https://en.wikipedia.org/wiki/Kuru_(disease))) Inspired by KEY\_ABRADE's answer when he mentioned the immune system: What if your species makes a form of antibodies that are stored in a similar way as the Kuru infected prions? They make the antibodies abundantly whilst they are growing up. But they stop making antibodies in their system when they come around the age of 18-20 and die as a result of a multitude of normal diseases. The only way they could gain more of these antibodies would then be via cannibalism. Even though body size (BMI) can vary wildly between humans, brain size is more or less the same (on average) per person. If, just like the infected prions with Kuru disease, the antibodies are mostly stored in the brain for some reason, this would also yield roughly the same amount per eaten person, no matter their body size. Consuming a normal adult would yield roughly 3 years of antibodies, after which they would need to cannibalise again. Eating children would therefore be less efficient, as they do not have the same amount of antibodies. Ofcourse these antibodies (and their entire immune system for that matter) would need to work differently than the ones we as normal humans have, as we continuously make new antibodies to replenish the dead ones. [Answer] I do not believe that any such mechanisms exist in nature in real life. However, let me make one up. Speciesus lemminginus has an exceptionally weak immune system, and members of this species tend to die of disease frequently. This is why their average lifespan is around twenty years. However, they are exceptionally robust in every other aspect of their biology; without this crippling tendency to die of disease, they can easily live longer than a human. Individuals of speciesus lemminginus are capable of integrating [memory T cells](https://en.wikipedia.org/wiki/Memory_T_cell) from other members of its species into their own immune systems, thereby increasing their immune system's knowledge of various types of pathogens, parasites, and bodily invaders of all kinds. Basically, the body of a member of this species sees a memory T cell show up inside it and goes "okey-dokey, that's-a mine now". They will have some special biochemical mechanism for extracting these cells from food without [lysing](https://en.wikipedia.org/wiki/Lysis) them. The problem is that these T cells are inside other members of its own species. The solution to that is for members of this species to eat other members of this species; preferably, ones they doesn't like, or ones that they're incapable of reproducing with. On the bright side, this means that this trait will likely stick around, as members that are capable of this are not only more immune to diseases than other members, but they're also good at killing off reproductive competition. The reason that this cannibalism is "uncooked" is because cooking destroys the memory T cells. They have to be taken directly from the source. I'm not sure how to make it "a maximum of three years per adult consumed", since that seems oddly specific, in my opinion, but I think I got the rest of it. By the way, this is personally how I explain vampires. [Answer] Biological? close enough. A long, long time ago the world was inhabited by a race of eternal immortals. These immortals achieved their immortality by mean of their advanced technology. Specifically, by microscopic nanobots that swarmed through their bodies, repairing damage at a cellular and even sub-cellular level. These nanobots were almost indestructible, could not replicate themselves, and were very, very, very expensive to make thus the immortals used only enough of them to keep themselves immortal. Then the immortals died off. (hey, it happens!) Who knows why, maybe they ascended to something more? Maye they got tired of life? Maybe they forgot how to make new nanobots? Regardless of the cause, their passing released the super-healing nanobots into the environment. Where the nanobots now inhabit your species of interest. But there are too few of the nanobots to make them immortal. Or even to extend their lifespan much. And their natural lifespan is so miserably short. (see footnote) Unless they get some more nanobots! But they are completely unaware of the little things. All they know is that if they eat the raw flesh of their own species, especially that of one that is unnaturally healthy and strong and old, then they inherit this vitality. (because they ingested 1 or 2 nanobots from the other, but they have no way of knowing this) Thus the cannibal gains strength from the act of cannibalism. Footnote: It is quite likely that your species is the same species as the original immortals, but their biology became so dependent on the support of the nanobots that their unassisted health and lifespans were badly compromised. It takes many thousands of the little nanobots to achieve immortality, and most of the species only have 1 or 2 in their bodies. (Never zero, because they do not even survive gestation/birth without the assistance!) It will take a lot of cannibalism to achieve the heights of the Old Ones. [Answer] If you think just a little adjacent to what you're describing, there're tons of examples of sort-of-similar things in nature that could be used. Start with reproduction. There're tons of biological organisms that can only reproduce in very specific environments - including the [parasite that causes malaria](https://www.cdc.gov/malaria/about/biology/index.html) for example. That reproduces only in the gut of a mosquito! Maybe your species has some symbiotic organism that works this way; they can only reproduce in your species' gut, and they help your species live longer in some way (fight off some other parasite, provide necessary elements/proteins, etc.). On a similar bent, you might have an enzyme that can't be synthesized by the species, but is necessary for survival (say a DNA repairing enzyme) - which is produced in the gut by a symbiotic organism (such as gut bacteria). This is, again, entirely normal for life on earth - except for the "cannibalism required" part, but that's not too hard to imagine; either the source material the enzyme acts on would need to be of that organism, or else the way they get the organism into the gut would be cannibalism (we do this, today, with [stool transplants](https://www.hopkinsmedicine.org/gastroenterology_hepatology/clinical_services/advanced_endoscopy/fecal_transplantation.html) - you'd just have to have a reason that this wouldn't work via the stool). Finally, you have life cycle transition as an option. Many species go through various cycles - think caterpillar -> pupae -> butterfly - and it's possible that the life cycle transition could be caused by cannibalism. Perhaps there is some horomone produced by a pre-transitioned adult that extends their life. This has the added advantage that it explains how this works practically speaking: the species can produce as many "children" as possible, but many fewer adults, since they have to eat the children. (I didn't say it was nice!) [Answer] You could just have and enzyme or mineral that occurs in the environment in exceedingly minuscule quantities. Evolution has enabled this species to sequester any excess of this essential substance in fatty deposits throughout the creatures body. The very young would need smaller amounts, but ever increasing as they approach adulthood. I would pay careful attention to balancing need for the substance from an evolutionary standpoint. Cannibalisms outside of reducing competition for an individual organism to increase its chances to reproduce its genes inside the success of the species is quite rare. [Answer] I can't imagine how evolution wouldn't quickly fix it, but: Your ephemeral species has a hormone that is essential for it's continued existence. Unfortunately, sexual maturity repurposes the system that produces it, from that point on the body relies on stores and when they're gone it dies. Unlike most such complex molecules this one can be obtained from food. Note that this means optimum cannibalism is of someone at the cusp of sexual maturity, not an adult. And it means you only need to eat the part that contains the storage, not the whole body. (However, it's possible that due to the covert nature of such actions that nobody has discovered that it's really only the one body part that matters, or perhaps the storage is dispersed somehow.) [Answer] The novel [Kren of the Mitchegai](https://www.baen.com/kren-of-the-mitchegai.html) describes a species that practises cannibalism. Juvenile Mitchegai are herbivorous, but if they don't get eaten by their carnivorous seniors, they switch to being carnivorous themselves. A juvenile or young adult Mitchegai isn't all that smart, but when an adult eats another Mitchegai, it adds its meal's brain mass to it's own rather than just digesting it. Eating a juvenile just makes the adult a little smarter, but if a young adult eats an old adult with a much greater brain mass, the old adult's greater brain mass dominates the younger's, and the older's mind effectively takes over the young adult's body. So, while Mitchegai bodies have a limited lifespan, by being eaten by a much younger, dumber individual, they achieve a significantly extended lifespan. The Mitchegai's brain cells are motile, and have a longer lifespan than the rest of the body. Once eaten, they travel through the body of the Mitchegai which ate them to the devourer's braincase, which is capable of great expansion. As a matter of interest, if a young Mitchegai eats only a little of an older, smarter Mitchegai's brain - possibly even leaving the older alive - their own mind doesn't get taken over, but they do gain some of the older's skills and knowledge. It isn't even entirely to the disadvantage of the older Mitchegai either... the older loses the skills/knowledges, but relearning them makes them more likely to achieve breakthrough discoveries in the field. ]
[Question] [ I'm learning about how to account for the fact that we can't really model (to a perfect degree of accuracy) an Orbital system with more than two bodies - I [very, very barely] understand this as the [n-Body Problem](https://www.youtube.com/watch?v=D89ngRr4uZg). Now, thinking about how to build a Dyson Swarm, the best method seems to be to [dismantle Mercury](https://www.youtube.com/watch?v=pP44EPBMb8A&ab_channel=Kurzgesagt%E2%80%93InaNutshell) My question is: Would moving this massive amount of materials from one part of the Solar System to another, cause the Solar System's balance to be thrown off? How would a future civilisation cater for this? [Answer] Mercury is the [least massive](https://en.wikipedia.org/wiki/Planetary_mass) among the planets of the solar system, with about 5% of Earth mass. For comparison our Moon is about 1% in mass with respect to Earth. The center of mass of the Mercury-Sun system is about 5 km from the center of the Sun, while Mercury is about 60 million km from it. 5 km is probably less than the precision with which we can measure the radius of the Sun or the position of a body in space. If that mass can cause any disturbance to the solar system, we are talking about something of second or third order with respect to the effects given by the Sun or Jupiter. There are more worrisome things than the mass of Mercury. [Answer] Considering Mercury is the innermost planet in our solar system, it probably wouldn't affect the stability at all. If you calculate the gravitational attraction of any other object towards the center of our solar system (where Mercury roughly is), the contribution from the Sun is so absolutely massive that you can completely ignore the contribution from Mercury. Thus dismantling it shouldn't really change much. [Answer] It has already been said, but here again. Mercury is the innermost planet. Compared to the mass of the sun, it's negligible. If you then move the mass around the sun, instead of a mass besides the sun, it'll make barely any difference to the whole. It's probably comparable with the biggest cargo ship full with lead going from one side to spread around evenly around the earth. The matter will change the distribution of the Earth's matter, but it'll not matter for the balance for it or the moon. You can basically ignore it. [Answer] Earth today is rotating slower than it should, because we lifted a lot of water to higher places, by building dams everywhere. I guess you didn't notice. That's because the effect is small. Really small. Some microseconds every day more or less... well, the GPS system DOES notice, a microsecond equaling to something between 20cm and 1m. We have a space observation program looking at pulsars just to determine those microseconds. Dyson habitats made from Mercury would probably lift themselves to earth' orbit for the nice temperature. So everything inside that orbit would fly around the sun a small bit slower or a little bit farther outside, everything outside that orbit wouldn't notice. Yes you can simulate the effects today already for many, many thousand years. I guess your civilization would do so before lifting something more important than mercury, and would even have better simulations than we have. Those habitats would probably have some kind of engine to avoid straying far from their course, or to avoid the occasional stray asteroid or comet. They would use those to counter any unwanted effect. ]
[Question] [ This question is related to a [SE:WB question](https://worldbuilding.stackexchange.com/questions/141298/aliens-englobed-the-solar-system-will-we-notice) of mine. I shelved the project about a year ago and am now dusting it off. To sum the concept up: several hundred million years ago a rather impenetrable barrier was erected by an unknown actor to encase the Solar System; extrasolar objects may enter the cordoned volume, which spans a couple dozen thousand AUs in diameter, but anything attempting to leave is quietly voided. (This means that objects that are "deleted" produce no emissions as a result of deletion.) I imagine that in the near future, perhaps in the 2060s, we'll get some real cosmic shots off, shooting away perhaps a thousand small nanocraft probes to a nearby candidate solar system, probably Proxima b, more or less as the [Breakthrough Initiative](https://breakthroughinitiatives.org/target/3) envisions it. (As of yet, the team leading the initiative finds no "dealbreakers" in the concept; however, there remain [challenges](https://breakthroughinitiatives.org/challenges/3) to be overcome.) Ultimately, the effort will fail as the ultra-velocity spacecraft ghost into the night, and we won't have any good idea why--or will we? This is essentially my dilemma. Could we explain the disappearances without invoking an alien presence? Or would the evidence against any unexpected nature of the interstellar medium/design flaw be too damning? Given the likely mission objectives of Starshot, what evidence could there even be? (Let's work with the Breakthrough Initiative concept proposal linked above, assuming their listed hinderences have been nominally surpassed and following their proposed target and mission objectives.) --- Knowing this will help me develop the, um, psychology of future space explorers/colonizers. Currently, I'm thinking that if the failure could be reasonably explained away without much woo-woo, I can put off/suppress the launch of further interstellar Starshot missions for the deployment of sophisticated space-based observatories and telescopes perhaps capable of directly-imaging exoplanet features, in effect making Starshot temporarily "obsolete" or out-competed. The Starshot arrays could then be relegated to intrasolar missions--at least for a while. If the failure can't be rationalized without giving people shivers, I will have to follow a different chain of events that thus alters the worldbuilding. After enough of Starshot attempts, it will become quite clear to people that something out there is seriously suspect. If, however, I can put off future attempts as mentioned previously, then I can allow space-based infrastructure to develop under a more hopeful and optimistic mindset. If not, then I expect an attitude of near-nihilism or a nonbelief in the infinite potential of humanity--and an uptick in the Lovecraftian horror genres. I don't expect the effect to be so great to produce super-radically different futures, but I do expect there to be a psychological difference among people should they learn this higher truth early on in spaceborne development. [Answer] That would be a scary thing to discover, however I doubt the first serious explanations as to why involve the word "Aliens". It will actually take us a while to realise they're all gone, and even longer to realise it occurred at the same distance from the sun, as they wont be in constant communication, they will just slowly start missing the weekly check-in. These probes aren't flying parallel to each other (they're scattered intentionally), nor would they be at the same distance from the sun as other probes, and there'd be a variation in speed. Depending on the launch timetables, the probes would just slowly miss check-ins and be written off, a few at a time, for months. We'll pull our hair out debugging the satellites, our knowledge of the universe, and physics, before we even propose aliens. Here's what I can think of: * Someone sabotaged the program. (Enter the FBI checking for people with radical anti-SETI beliefs or something). * Failure of earth based radio software. (It'll get debugged and rewritten). * Atomic clock failure, so were listening at the wrong time, or in the wrong place. (We will recalibrate all the clocks) * Simultaneous failure of all 3-5 earth based receivers hardware. (Its more likely than hundreds of transmitting antennas failing. The hardware will be checked. Bird poo will be swept out and itll be polished). * Dark matter / energy interacts with radio signals, reducing their strength over distance. What we previously thought was a weak radio signal was actually really strong. (Next batch will have stronger radios.). * These probes were mass produced, and the same manufacturing error seeped into all the designs. (eg tin whiskers, temperate stresses detach a solder joint, some part overheating or freezing). (Next batch will be better engineered) * A software glitch occurred. Eg they lost light calibration, can't find stars, and can't orient their antenna correctly. Or just bluescreened. (Next batch will have redundant computers) * The dispenser has a silently malfunction mode - probes are travelling with parts of their final stage / cover / case / still in their shipping racks / etc. Or the dispenser magnetised / or statically charged / or something else the probes, making them all fail prematurely (new dispenser will be designed). * A star was hidden behind a black object invisible to us, when the probes get far enough out they can see it, their internal star maps are wrong, and they can't get their bearings, so antennae isn't pointed in the right direction. (Next batch will be written to survive this) * Conversely, a star could only be visible through a narrow slit in a black object, so when the probes get a bit out from Earth, a key navigation star disappears. * There are planets / Dwarf planets going out a lot further than we know. We just sent thousands of interstellar probes to crash into a few giant balls of liquid helium (or some other crazy thing) that we didn't know existed. (Queue us rewriting how the solar system formed) * Our sun has a dust cloud around it, when you get far enough through it, you can't see our sun looking back as clearly as we thought. (Next batch will have a more powerful radio, and not visually search for the sun). * There is a galactic background noise interfering with our chosen radio frequency. (Next batch will use different radio technology) * There is a shell of abrasive particles out there, like diamond grid cloud, and they scratch the crap out of things to the point they don't work. (armour-plated probes next time) * There are a few high mass objects out there that haven't been detected, and they're refracting the radio signals, or changed the trajectory of the probes. (We panic search for Black Holes that aren't emitting Hawking radiation). * The solar wind is interfering with radio signals, refracting them or frequency shifting them. (Next batch might use laser communication, or some other tech) * Cosmic background radiation is more dangerous than we thought, our solar wind is pushing away cosmic rays that are EMPing our probes. (Next batch will have a stronger faraday cage) * Wandering "rogue" planets are out there in large numbers, and their gravity swung the probes. (Queue a mission to check for them) * We've made some catastrophic error in calculations of the universe (eg maybe the speed of light isn't a constant). (We'll try to rewrite physics to explain what's going on) Not all these are "likely", but they'll be proposed to try to figure it out. You dont want to be the first NASA engineer to say "must be aliens!". The process of Launch, Die, Analyse, Redesign would go on many times. Potentially dozens of times. We will be trying to disprove everything else we can think of before we go "Ok, it must be aliens." Those launches will be years, maybe decades apart, and it may be demoralising enough failing over and over and not knowing why that we stop trying for long periods. Unless we see evidence in some other way (An asteroid with a unusual cut from partially intersecting the field, for example), we probably wouldn't suspect aliens until we see a video of the field eating matter. And it'll probably be the last few seconds of a live feed from a camera on a (sadly, probably manned) space craft sent there specifically with no purpose other than to investigate wtf is going on at about 10,000AU [Answer] The Second We Start Losing Multiple Probes at the Same Distance from the Sun the Jig is Up It would take approximately 30 years of "design/build time" along with the travel time it takes probes to reach the barrier for the world to consider aliens the primary cause of probe loss. Ash has a lovely list of all the things scientists would think when the first probe is lost. Space dust, random failure of receiver/emitter and so on. However you can rule out multiple problems per launch, and indeed scientists being scientists they probably would. Once you start losing multiple probes at the same range the suspicions are going to pile up pretty quickly. Especially once people start aiming for other parts of the sky and getting the same result. You sent a probe to Alpha Centauri. The probe loses signal a Light-day out from the sun(122ish AU, roughly the distance from the sun to the edge of the solar system). So you boost the power and harden the systems and send out another probe, had to be something mechanical. If someone's real paranoid you'll also increase the frequency of reporting as you near the 122 AU limit. Second wave probe still goes dark a light-day out. At this point the head scratching increases. But still, can't be aliens, plenty of other things could go wrong! So you do it again, increasing the probe's ability to gather data about their trip, just in case. You lose the probe again.... exactly where the last ones were lost. Paranoia in the scientific community is now REAL high. You fire off another two probes, of a simpler design, at slightly different patches of the sky because at this point you don't want to waste multi-billion dollar solar-system-scanning probes when what you REALLY want to know is Why Do The Probes Die at 122 AU. You have them continually broadcasting once they get close to The Limit. They go dark at the exact same distance as the last set. Governments are now Very Concerned, and it wouldn't surprise me at all if the word aliens started getting thrown around. Another pair of probes are launched, this time in tandem, with one following in visual range of the lead probe. The lead probe hits 122 AU, and dissolves. The trailing probe sends back the intel, and is lost soon after. Everyone now must admit that we live in some sort of Galactic Zoo. So that's 5 iterations from First Loss to cue hand gesture Aliens. You could shrink it to maybe 3 or increase it a few more times, but scientists are real smart and probes are build with every-conceivable-failsafe-and-variable in mind today, so it doesn't seem likely you could keep doing this ad-nauseam. Where does that leave us? It can be a decade to design, build, and launch a probe, and 5 years seems like a pretty fast turnaround. Plus travel time, which is whatever you make of it. Even if you wanted to launch the same probe again you probably wouldn't, just because of how bureaucracy works. (When probes crash they tend to add on new tech to the next probe even though it's trying to do the exact same thing the lost one was, rather than just re-build the already designed probe. Usually because the new tech is miles better but it still takes redesign time.) So say 5 years between first loss and second launch. Then 10 years between the second and third wave (because at this point you're essentially designing new probes) Then 5 years again (because you're using third-wave design, more or less, just aimed at another spot) then 10 years for the final pair. Once you start factoring in travel time though it could be a century or more (Space is BIG, takes a long time to get places) before your poor Terrans realize what's what though, and that seems like plenty of time for happy and hopeful colonies on Mars or Europa or wherever. If your travel times are more like a year or two between probes it wouldn't be too hard to imagine budget fights meaning that Starshot II takes 20 years to be approved because hey, the guys wanting to send a probe into Neptune's atmosphere have a REALLY great proposal, or Why Do Probes Die At 122AU Probe I never getting off the ground because Starshot I and II bankrupted the company and why should some OTHER company figure it out when mining the Asteroid Belt is a more lucrative idea? Conversely if you have some competing companies/nations and 3 different Starshot probes are launched at Alpha Centauri a month apart who then get into a Moon-Race-esq contest to figure out WHY they were lost you could come to the "Alien Zoo" conclusion within a decade, minus travel-time. ]
[Question] [ I'm working on a space exploration game where humanity has become extinct and Earth is no longer inhabitable. A lone AI activates and its main directive is to find another world where humanity can be given a second chance (via cryogenized embryos). The setting is one where space travel happens at sublight speed. Imagine some sort of interstellar Kerbal Space Program where you send out probes to other star systems. In the context of the game, a world similar to Earth is incredibly rare (which might very well be the actual truth) and we are potentially in a desolate corner of the galaxy (no aliens). Assume the AI can function for thousands of years (that would also be an element of the game). At some point an Earthlike planet is found, but it is not a perfect copy of Earth: too cold, too hot, no water, too much water. Something's not ideal. How could an AI weigh whether to focus on terraforming the found planet versus continuing the search? Which terraformable characteristics would be addressable with realistic technology and hundreds or thousands of years of waiting? And which would be lost causes? I imagine some planets would be unterraformable (or not worth the effort vs the results) without "type 3" technology (e.g. tidally locked planets, those without a magnetosphere, changing a planet's orbit...). Whereas maybe other actions (melting the polar caps or crashing comets to increase the water amount) might be more feasible? But if terraforming is always feasible, then the search might end just after starting, or not start at all (just focus on Mars?). So I might have to rework the game idea. [Answer] This isn't an Either-or Proposition. Terraforming is going to be a long process, and will require using resources on the target planet to successfully complete. You'll need to build infrastructure dirtside to change the atmosphere, and place the biologicals you need to support Human life. So instead of just searching for a single Earthlike planet, and putting all the eggs in one basket, the AI should be sending probes that are capable of building robotic factories that can build more probes, and capable of building the factories needed to start terraforming. When the probe gets to a suitable target system, it can then both build more probes to throw to other potential targets, and the terraforming infrastructure. If the terraforming effort fails, or if the world was not as suitable as initially thought, just build more probefacs, and throw them to other candidate stars. When the terraforming is reported complete on any of the worlds that are being processed, that world gets sent enough embryos to spawn a viable population of humanity from the nearest supply. Meanwhile, millions of other probefacs are continuing to scour the galaxy for Terraformable worlds, or resources to build more probefacs, expanding exponentially. You did tell the AI to consider occupied worlds as non-terraformable, right? Huh, something's been detected at the edge of the Solar System... [Answer] ## Solar radiation The amount of energy the planet receives from the star can be altered by moving it closer or further away in its orbit, however it is not something that a civilization smaller than K2 could easily do. In the same way it would be very difficult to change the orbit in order to become less eccentric. ## Gravity This makes the dream of terraforming Mars close to delusion. A planet with a surface gravity much greater or much less than the 9.81 m / s² that we have on Earth will affect all of biosphere. In addition, even with a powerful magnetic field protecting from the solar wind, there is atmospheric escape with a low gravity; and this planets will already have an atmosphere poor in light elements that AI will have to import. In worlds with much greater gravity the atmosphere will have more pressure, requiring it to be less massive, and making the radiation protective layer above the surface much smaller. ## Magnetic field This is quite simple. Even NASA has a proposal for an [artificial magnetic field on Mars](https://phys.org/news/2017-03-nasa-magnetic-shield-mars-atmosphere.html). ## Rotation This is a problem that appears for a terraforming of Venus that in a long-term project can be easily executed. The rotational energy of the Earth is 2.58 e+ 29 J while the rotational energy of Venus is 1.38 e+ 25 J. Applying more energy by dragging the atmosphere over the crust and bombarding lighter bodies would not be something very extraordinary ## Axis inclination The problem here is not exactly on a big or small slope, although a planet like Uranus will make things quite difficult. Having a more or less stable axis, unlike Mars, can be important in the long run. Having a satellite big or enough to maintain balance can be attractive, although we don't know how common it is for a rocky planet to have a moon so big that it appears to be a double system. However, a large planet like Earth is also more stable than a smaller one like Mars. ## Crust thickness A very thick crust will prevent tectonism and AI will have to work in other ways to enable long cycles of carbon and other elements. ## Atmosphere Both the mass and the composition must be taken into account. This part is relatively easy, unless the planet orbits a star very different from our Sun (which will somehow make the planet unviable), the composition of the other worlds of the system must have the missing volatiles. Extracting excesses from a very dense atmosphere on a suitable planet is perhaps a much more complicated activity than including. ## Water Hydrosphere and lithosphere are worked together with the thickness of the crust and atmosphere. They don't offer much of a challenge then. ## Biosphere AI will certainly have in addition to human embryos all sorts of microorganisms, seeds and embryos in a food chain complete enough to support human needs, right? [Answer] Why not build large spaced based biospheres while searching for habitable worlds? Your biggest problem is that it will take time to find suitable words regardless of whether they need Terra-forming or not. As pointed out by Rodolfo (above) any planet you consider for Terra-forming is going to have to meet some very specific criteria and the likelihood of finding suitable worlds close by is not high. And since you've already stated that travel between stars occurs at 'conventional' sub light speeds this by default means that just reaching the nearest suitable stars is likely to take decades if not centuries. Add even more time for your probes to report back followed by more decades still while colonizing missions are sent and your mission completion time blows out enormously. You can shave centuries of the recovery effort however by targeting local stars that don't have suitable planets but which are rich in minerals and elements needed for large scale space construction. With enough local resources its possible to build enormous (continent sized) rotating habitats. And you will many more star systems suited for habitat construction than you will ones with potential new 'Earths'. The best part being you can still build habitats while the search for Earth-like words continues. Eventually of course you will finds suitable worlds but by the time you do you can have scores of habitats up and running housing hundreds of millions of people, plants and animals sharing information and technology and acting like stepping stones for the transfer of people and resources if required. Clarification - as noted below in the comments; there's no reason the process wouldn't start in the Sol system first after all the engineering problems are resolved. However the machine may also consider that since we managed to nearly wipe ourselves out once before its odds of long term success increase if new populations are also located elsewhere outside the solar system. [Answer] Sit on the Moon and wait for a few thousand years Eventually plant life will take over and clear up the mess on Earth. The new Earth will be rich in oxygen and there's a good chance fish will have survived. Given that the AI is intelligent and has unlimited time, this is the least risky and least expensive strategy. If after, say, 100,000 years (1 million years?), Earth is still not clean, then it's worth trying something else, e.g. Terraform the Moon It's nearby and in the right zone. It just needs technology that we are already thinking about to make it habitable. If the Earth is unrecoverable then the AI can make the Moon into an ideal habitat and humans can live there forever. ]
[Question] [ I'm writing a rough sketch for a book about a world where people sorta violently and suddenly get barely working superpowers. That is every time each person uses their power they run the risk of killing themselves. (I already almost set up the world with powers like invisibility, intangibility, super speed, their drawbacks and all.) Now I'm struggling to flesh out a mad psycho character with an accelerated healing factor. This world is very much grounded in reality. Points to keep in mind: 1. Using the healing factor also (ironically) runs the chance of potentially killing him every single time 2. The healing factor must have a major physical drawback/kink 3. He can only barely heal from bullet wounds, cuts and broken or dislocated bones. But he still keeps on fighting. Really need help, 'cause I have this whole world setup and he's the guy that makes the readers realize how dangerous everyday life in this world can be. EDIT Form the answers I got,the character is a man of average build. When he is injured his body uses every resource it has at hand and heals him but leaves him frail and at the point of starvation. The newly healed parts carry the risk of potentially becoming cancerous. The speed at which the repair is done causes a lot of discharge in the form of heat,requiring him to cool down himself. (For reference,in my world the one of the lead characters with superspeed has a well developed and more branched circulatory system concentrated in and around his legs. The muscle cells in his legs have a new type of protein that causes them to contract way more faster in response to a signal. This only pertains to his legs. He can only run at about 101m/hr or 180km/s and that too for barely a 1 minute. But he only only run in one direction,he cannot change directions while running and he only has a normal human level perception of time. Running at high speeds causes his bones to have multiple severe micro fractures and he can't breathe properly while running. His whole body is hurt from the air resistance as well,he also has to build up speed and constantly hits into thing injuring him. And he suffers from the effects of inertia. He constantly has to see his doctor and running at high speeds for even once in a day leaves him sore and unable to walk for 2-3 days. He also has to eat a lot for the required energy and running leaves him on the brink of death ) The mad psycho character needs to heal bullet wounds,cuts and broken or dislocated bones in under a minute. The healing does not have to proper as well. And no stem cells and definitely no nanobots. The power is a mix of torture,stress,trauma and mutation [Answer] Healing takes a ton of energy and materials to kill off damaged cells and replace all the damaged/lost cells with fresh new one's. Healing factors like those of Wolverine should kill him within a few bullets as his body uses up all it's reserves and can't sustain the remaining cells. The mad psycho character would become extremely tired and probably metabolize a portion of his fatcells into energy and materials, making him a thin, haunted man quickly after any fight where he gets wounded. Edit: This should be interesting: <https://www.youtube.com/watch?v=CLY-FMxsb2U> [Answer] Regeneration as seen in comic books and movoes would in the very least require an unrealistic amount of stem cells available in the body. When we bleed, platelets around the wound site secrete chemical signals which attract more platelets there, and causes them to become modified, so that together they can form a clot: ![The coagulation cascade](https://i.stack.imgur.com/0vy74.png) It may be that in the body of a character with super regeneration, platelets go through a process called [dedifferentiation](https://en.wikipedia.org/wiki/Cellular_differentiation#Dedifferentiation): > > Dedifferentiation, or integration is a cellular process often seen in more basal life forms such as worms and amphibians in which a partially or terminally differentiated cell reverts to an earlier developmental stage, usually as part of a regenerative process. > > > But some stem cells migh stick to each other forming huge balls inside the character's vessels. He will be in extreme risk of stem cell thrombosis every time he has even the slightest paper cut. And if the stem cells flow away in the bloodstream and coagulate somewhere other than the wound site, they might obstruct vessels at the heart, lungs or brain. In such cases the character will croak faster than he can say "healing factor". [Answer] Well, if you're going for "mad psycho" anyways..... Cannibalism. And Cancer. You're going to be using a LOT of energy to repair all those broken bones and bullet holes. Fat and meat are high-energy-density foods. You could make him MORE fragile by giving him a regular human's metabolic rate. Meaning that every time he used his power, he'd go from healthy to half-starved over the course of a week or a month and he'd be healed. Or you could go all the way. Give him the metabolic enhancement and healing factor. He can heal all he wants as long as he can consume the calories, calcium, and sugars necessary to keep his body running, but since it's growing back so quickly, it's mostly weak and cancerous. [Answer] Look at animals that can regrow limbs and tails and such; mostly amphibians and reptiles that can do this. It is slow, but you could explain it using similar biological mechanisms and just upping the metabolism rate. As another answer stated, this would - realistically - require an insane amount of calories and proteins and calcium and such, so a "realistically" regenerating person would be constantly hungry, especially after any use of the power, and probably need crazy amounts of certain nutritional supplements as you simply cannot get enough of those things from food alone. ]
[Question] [ As I'm sure anyone reading this knows, our body parts move via the brain signaling the appropriate muscles to contract or expand. Now, for hair to function the way it does - its texture, malleability, etc. - it doesn't seem plausible for prehensile hair to happen with a humanoid with muscles all the way up and down every strand of hair. Plus, that would probably result in a lot of blood gushing every time you got a hair cut. So how else could prehensile hair be explained while still rooted in hard science? (Or, more generally, is it possible?) Specifically, I'm looking for a way to not only move hair, but also to do so with enough force that the user can grab onto something with it. EDIT: There are a ton of good answers down there. I accepted the one that worked best for me, but for anyone else who wants a go at this, that's not the only one that looks like it works. [Answer] So I don't think this is really plausible using hard-science. However, you tagged this with [science-based] rather than [hard-science], and if the [science-based] tag is willing to engage in some heavy drinking and look the other way, we may be able to pull something together that looks at least somewhat science based. I'd like to start with a prototype for the motor: [Nitenol wire](https://en.wikipedia.org/wiki/Nickel_titanium) [![Nitenol wire unwinding](https://i.stack.imgur.com/J2DzWm.jpg)](https://i.stack.imgur.com/J2DzWm.jpg) Nitenol has what we call "shape memory." If high heat is applied to the wire, the phase transitions it undergoes cause it to "remember" that shape. Later, the wire can be bent into nearly any shape, and if a light heat is applied, the wire regains its shape. This has many uses in industry, particularly in the biomedical field where it lets surgeons implant something thin, and then let it acquire its shape once it is in place. If our hair had some of these shape memory properties, it could grasp things. Of course, this is certainly far from a complete story. Nitenol's memory is a one way trip. It's actually just going from a highly energetic "stretched" form to its natural lower energy form dictated by memory of when it was last cooled from high heat. If we used nitenol for our hair, it could reach out and grab something, but it couldn't let go. If it did have a way to "let go," it would have to let go into a flaccid useless state with even less energy than its memory form. To do anything else would require the hair to be "alive" and metabolizing, and that would create a whole set of biological requirements that hair just isn't ready for (see the other answers for why). To make this work, we're going to give [science-based] a few good shots of Absinthe, and while it's babbling on about the green fairy, we're going to make the assertion that "proteins are magical." We do some pretty spectacular things with proteins in biology, many of which are far and beyond my understanding. So let's assume we can make some pretty stellar protien structures with some remarkable properties. They can't break the laws of physics. In particular, conservation of energy is going to be a mighty challenge here, but we'll assume they're pretty darn nifty compounds. The first challenge we'll have with prehensile hair is the need for control. If you suggest a head full of memory wire to any woman, and she'll let you know just how bad of an idea that is: [![enter image description here](https://i.stack.imgur.com/upfbrm.jpg)](https://i.stack.imgur.com/upfbrm.jpg) We're going to need to be very careful with our protien structures to make sure that we don't just create this biosphere's worst version of bed head ever. Instead, we're going to create what appears to be every woman's dream: hair that can transition from straight to curly to straight to curly. This would be very hard for a simple crystalline structure like nitenol, but isn't all that far from plausible for proteins. To communicate with this hair, we're going to need a nervous system. However, we can't afford to have live nerves in the hair, so we're going to have to be a bit more frugal. Since [science-based] is still suffering from a pretty bad hangover at this point, let's permit the hair to be managed with an all digital signaling system. This sidesteps all sorts of complexities which arise with the real signaling systems of the human body. We can get away with this because, unlike an arm or a leg, hair is replaceable. It's constantly growing outwards, so its signaling system doesn't have to keep functioning for 70 or 80 years. Depending on how fast this hair grows, it might only have to function for 5. We're going to want more than 2 states for each hair: curly and not. Really what we're going to want for prehensile hair is to have many addressable regions of hair, each of which can be made curly or not. Fortunately, by going digital, we can use prior art for this. There's a very well known protocol known as JTAG, which is fundamentally based on the idea of a shift register. You can connect a bunch of these devices into a line, and then begin "shifting" bits in. Every time you push a bit into the front, every device shifts one bit down the chain in order to make room for it, like a bucket brigade. We can build something like this with proteins using something like Jacob's ladder. [![Jacob's Ladder](https://i.stack.imgur.com/MlwZcm.jpg)](https://i.stack.imgur.com/MlwZcm.jpg) Each time you want to shift data down, you put a new protien it, and rotate the entire chain to move data along. This requires energy, but that energy can be supplied in the root, where the data originates. The root could provide all of the energy for this, because it's only signalling energy. It's not doing any real work like holding up a cup of coffee or swinging from a limb. Perhaps each section of hair gets 8 states (3 bit shift register). They correspond to commands for what you want the hair to do. Now we can shift data to each section of hair, slowly but surely. I don't think we're going to have prehensile hair headbanging to metal with this approach, but we might be able to grab a branch like a sloth! With JTAG, we signal that we're ready for "action" with an extra signal, TMS. This signal is sent to every part of the chain to announce to the chain "these bits are your actual command, rather than just being data to pass down the bucket brigade. Do something with it." This could be tricky and very non-organic, so I'm going to spice it up a bit. While I'm not ready to provide full-blown neurons in the hair, I do think we can do a tiny bit of processing using the energy we can transmit from the hair follicles. I'd like to give every segment of the hair a [linear feedback shift register (LFSR)](https://en.wikipedia.org/wiki/Linear-feedback_shift_register). This is a really really simple digital device which really just mixes up the bits a bit. This doesn't really add all that much extra duty to my extravagantly overly complicated "science-based" solution, but what it does mean is that each section of hair sees a message that's slightly different than the previous section did. I'll then have the "go" message come from the tips rather than the follicle. This does a few things that are very useful: * It gives a signal to let the hair strand know that every single part of the strand has received the correct signal -- we've filled up all of the chain with the right bits. * It gives us a way to address the individual parts of the strand. Technically we could have just created a unique ID to each part, but that has a biological challenge associated with it. We have to remember that anything like hair is going to be attacked at a biological level if it has energy in it. That's why hair and nails are so resilient -- almost nothing can consume the energy in them. If I made it easy for some parasite to latch on and capture the mechanical energy from the hair, then some parasite would evolve. The randomness of using a LFSR makes it much harder for a parasite to grab any amount of energy out of the mechanical system. * It provides feedback, similar to the TDO line of JTAG. If the hair is not properly functioning, the creature might command part of the hair to do something, just to see where the damage is. * Predicting the behavior of these LFSRs is easy if you're the brain strapped to them, and have literally hundreds of opportunities to figure them out. In hair combat, it will be hard for the opponent to learn the exact structures of your LFSRs to manipulate your hair against you. I just checked on [science-based], and it's still trying exotic solutions for the hangover I gave it, like those from [this list](http://gizmodo.com/5936409/the-worlds-19-weirdest-hangover-remedies), so I think I still have a little time left. We need to talk about energy. Nothing I've done so far has a remotely high enough power, in terms of watts, to manage prehensile hair. I've had to do this intentionally. If there's a source of power, I have to protect it biologically from parasites and such. The less universally accessible power I put in this system, the better. However, at some point, I need enough energy built up into the system to actually do something useful. For this, I introduce "maintenance mode." One of the selectable modes for each hair segment is a low energy maintenance mode. This is most likely a very curly shape. This is the lowest energy mode which any hair segment can reach, so no matter what we do with the hair, eventually every segment reaches this curly form. The entire purpose of this form is to capture mechanical energy. The owner of the hair can manually stretch the hair, like stretching nitenol wire, adding energy into the system. If they stretch it far enough, it can eventually return to the initial high energy "straight" mode which is ready to do anything. This stores the energy in mechanical stresses rather than high energy molecules like glucose, so it should be harder for parasites to learn to take advantage of that energy source. Also interesting would be that this charging technique could be done to individual segments. It doesn't even need to be the whole strand that is charged at once. I could see this being used two ways. One is that a person could move their prehensile hair around towards their arms, so that they can use the chemical energy in their arm muscles to store energy into their hair. This might be seen as a sort of "grooming" action, like a duck pruning their feathers. The other interesting thing is that hair segments could "charge" each other. You could use one segment of prehensile hair to pull at another segment to recharge it. Of course this would be a lossy process. You'd expend far more energy from the donor segment than you'd gain in the recipient segment, but if it happened to be that you needed that particular section of your hair energized more, you might see it. One sign of nervousness might be the individual's hair writhing against itself trying find the best distribution of energy. I think [science-based] may be looking my way, so it's time to make my exit. Hopefully that helped! [Answer] Hair that is iron-based could be manipulated with internal magnetic fields (say, just a bit of iron at the tip of each hair so it can be attracted/repelled as needed). It wouldn't have a strong grip one hair at a time, but Velcro gets lots of grip by grabbing on collectively. [Answer] Short answer: It's not possible. Anything that's fine enough to be hairlike won't be strong enough to grasp objects firmly. Prehensile tails require both muscles strong enough for grasping as well as the skeletal structure to support them. Something like a cephalopod's arm wouldn't work because they're dependent on being submerged to have a full range of motion. You could handwave the structural problems and make up some nonsense about supermaterial micro-robotic arms, but that's not really science-based. You could rig up a system to provide hyper-precise control of 100,000 hairs in realtime. But you'd need to have many (at least 1/cm) control points for each strand of hair to be able to wrap it around something. Not to mention the computational challenges of tracking the position of every control point and the soft body inverse kinematic simulation needed to control their movement. Then you'd need an accurate map of the environment for the hair to interact with it since you'd lack any form of sensory feedback. All this for what is functionally an extra arm attached to a less structurally sound location. [Answer] Yes, it is possible. See [cilia](https://en.m.wikipedia.org/wiki/Cilium) and [flagellum](https://en.m.wikipedia.org/wiki/Flagellum). It may not be likely on the macro scale, but it is possible. You may end up with "hair" that is the thickness of a ribbon snake, if you want any strength to it, and of course damage to the members would likely feel quite intense. You may also not get much density to the hair per square inch of skin surface, more of a medusa effect rather than proper hair. But on the plus side it could be much more colorful than real hair, even chromomorphic! [Answer] No, it's not possible. Did you know that any visible hair you see is already "dead"? None of the cells in there are alive anymore. However, if you're okay with a bunch of mini monkey tails growing out of your head you could potentially have "hair" that can grab things. ]
[Question] [ Probably one of the many main-stay go to weapons for most sci-fi settings. How exactly would you go about making the blade "vibrate" or resonate at in such a way to increase its cutting power? Would you even be able to hold on to such a weapon and would the weapon eventually destroy itself? [Answer] Thanks to friendly redit user "Uchihakengura" who was answering a question about the high frequency blade from Metal Gear rising (It's basically a vibroblade in everything but name and in the Metal Gear universe) we have the the following breakdown > > "A blade, even a small one, works on a simple principle. Force > applied > Friction of the cut material. A knife, a regular kitchen > knife, sharpened to a micrometer tip, where the edge width is > 1.0x10-7meter wide, would require a very small amount of force to cut something like say, a watermelon rind. Cutting through it would take > some force, but pushing downward with a blade it would go through with > some effort. > > > Now, if you add vibrations to the knife itself, those > vibrations would allow the blade itself to wiggle back and forth. Say, > indude a 10Khz vibration into the blade. That's playing a sound, that > has a frequency of 10,000 vibrations/second. Science definition: 1 > Hertz = period between the Crest and Trough of a wave. 10,000 Hertz, > or 10KiloHertz means that 10,000 of these crests and troughs will pass > every second. That said, a 10Khz sound induced would cause the blade > to osculate, even microscopically, in response to the sound. The > blades vibrations would act by forcing additional energy into the > blade that would translate into the cut surface quickly and help > separate the materials easier by means of creating a small, albeit > microscopic pocket of air between the knife and the watermelon rind > that you would be cutting. > > > Consider this, a Turkey Slicer, oscillates > back and forth to cut through turkey. This is the same concept, > instead of going back and forth many times a second though, you would > be making the blade go side to side. The faster the waves, and the > higher the frequency, theoretically, the more you would see the effect > to a point. > > > There is cause for concern when doing something of this > nature however. Once you reach a certain point, you may wind up > shattering the knife, because the oscillations are to much for the > handle, metal, or blade to stand and could wind up damaging the blade. > When this happens, best to get a new knife." > > > (different post by the same user one day later) > > "The oscillations caused by a frequency > going through the blade are debated every now and then as to what the > affects may actually be. Some say that inducing a high frequency, high > amplitude wave would be damaging or disrupting to the user. > > > For example, > grabbing the handle of a push mower, or a chainsaw. These Items put > off a low frequency (mowers 60-200 rotations per second and chainsaw > blades travel along the blade track at around 150 revolutions per > second.) but also have high amplitude. Lawnmowers for example, > encounter blade instability and many, many points of drag that make > the blades "wobble" creating additional, interfering, points of impact > making its vibrations do strange things. Chainsaws, on the other hand, > have a highly serrated edge that creates hundreds of "teeth" hitting > and chewing at wood when pressed down on a log. These teeth all create > a similar instance of multiple points of drag and slow the blade down, > and in such create more interfering vibrations. > > > The concept for a > sword however, is much different than this thinking. In the sword > forging community there is a concept to use just this, its called > Harmonic Balance. > > > [To borrow a post...](http://www.swordforum.com/forums/showthread.php?42946-Harmonic-Balance-Introduction) > > > > > > > What Harmonic Balance does for a > > sword- prevent's shock from being transmitted to the users hand when > > striking with the sword. This conserves energy- the sword doesn't > > 'waste' energy shaking the user even when the strike lands off of the > > COP. It also prevents the user from losing control of the sword > > because of vibration transmitted to the user's hand. It also minimizes > > the sword's tendency to damage it's hilt assembly through vibration. > > All good things! > > > > > > > > > Michael Tinker Pearce Moderator Sword Maker SFI > Honorary Educational Advisor This would go to say that Vibrations are > reduced from travelling through the blade into the user of the sword, > and that vibrations are bad. However, on the opposite side of the > scale we can use the same principal, but make a simple tweak. Use a > Super high resonant frequency wave, or an Ultrasonic wave to generate > an extremely high frequency wave, with a very small amplitude. These > "micro vibrations" would be invisible to the naked eye, and may be > felt to a small degree, but overall in the handle would be > ineffective. > > > What this means for the blade - The increased, high > frequency would cause the blade to move back and forth so fast, that > it would literally begin to obliterate things on contact at a > microscopic level. As far as the frequency, were talking... 20Ghz, or > 50 Ghz. That's 50-billion vibrations per second." > > > original post can be found at <https://www.reddit.com/r/GameTheorists/comments/2e4cz7/is_the_high_frequency_sword_in_metal_gear_rising/> [Answer] ## Vibro Consider the powered hand held jigsaw. [![enter image description here](https://i.stack.imgur.com/eGRqo.jpg)](https://i.stack.imgur.com/eGRqo.jpg) This is a vibro-blade in all but name and high impact use. It has a short serrated blade that's rapidly vibrated to give its cutting action. The vibration is a highly effective and it's unlikely to shake itself to pieces. However it has some downsides. In this case you can clearly see that the blade is considerably lighter than the handle. This balance needs to be maintained to get the vibro-blade rather than a static blade with a vibro-handle. In long term use you also get the risk of what's known as [Vibration White Finger](http://www.nhs.uk/Conditions/Raynauds-phenomenon/Pages/Causes.aspx). ## Blade Consider a sword. [![enter image description here](https://i.stack.imgur.com/RhUSC.jpg)](https://i.stack.imgur.com/RhUSC.jpg) Most of the weight is in the blade. To make this blade vibrate we either need to massively increase the weight of the handle, massively decrease the weight of the blade, or both. Let's do both [![enter image description here](https://i.stack.imgur.com/5CH2d.jpg)](https://i.stack.imgur.com/5CH2d.jpg) Now we're looking at something that could be used as a vibro-blade. You'd still have to take a lot more weight off that blade and unless you have the ability to cut through 2 inches of steel on contact the chances are you wouldn't be able to parry. Now I'm not bumping the technology up very much here. Vibrations are still macro and it's almost within currently available technology. You just need to sort out the weight and edge on the blade. [Answer] The way the vibrating blade could be powered is by exploiting the piezoelectric effect, where some materials can be induced to expand or contract by applying and releasing an electric field. a rapidly varying field would see the material expanding and contacting rapidly, which could be used to induce vibration in a blade attached to the material (say screwed on the tang of the blade), or making the material out of the piezoelectric material itself (although this is highly problematic, since the material property which makes for a good blade may not be present in the piezoelectric materials). Several posters have already commented on the size and mass of the power source, but another factor which would have to be taken into consideration is wast heat. The conversion of electrical energy into the vibrational motion of the piezoelectric crystal isn't going to be 100% effective, and the blade will also heat up to a certain extent because extra energy is being delivered into it. The user will find the grip becoming uncomfortably hot in a short time (and if the battery or generator is in the pommel, holding the sword would become tricky over a long period. A hot Lithium ion battery isn't something to mess with...). The blade will act as a radiator to a certain extent, and "sculpting" the blade to increase surface area and wielding the blade in a continuing series of motions to induce airflow over the blade will help the user keep the system cool. Fights with edged weapons could become frantic slashing battles as the users attempt to keep the blades in motion to cool the vibrational machinery concealed in the grip and pommel. [Answer] Other answers are quite good, but I feel that I can add a bit of interesting information: --- Answering last point of your question: > > Would you even be able to hold on to such a weapon > > > 1. If we assume that vibroknife must permanently physically vibrate in any direction then without protection in long term, it can cause [carpal tunnel syndrome](https://en.wikipedia.org/wiki/Carpal_tunnel_syndrome). Also it would be quite unhandy. But what engineers designing that thing could do - they can add bridge between handle and the blade with an engine that vibrates in an opposite amplitude and frequency. Or designers could take a cruder route - and add some material and/or set of springs to handle that dampers vibrations. 2. If we assume that vibroknife must physically vibrate only during the moments of hit and penetration (and user has some kind of trigger to control it) then you could skip dampers part I mentioned in my answer above. 3. It could be requirement for user of vibroblade to either have their hands altered (cyberhands) or have external power armor unit for upper part of their body to compensate for any vibrations (but this whole "3" design feels too overcomplex). > > and would the weapon eventually destroy itself? > > > Eventually yes - but you can take a look at real-world electric hand-tools that produce vibrations... drills, saws, chainsaws. Those things could be built to last tens of years. And bear in mind - real-world guns and swords are not designed to last forever. It's also possible that "vibro" part in "vibroblade" is scientific or brand name for some kind of effect or technology that has no connection to physical vibrations - like some kind of electric current that strengthens the bonds between blade micro parts composed from specific materials; this theoretical 'current' makes blade hard or robust and keeping edge, yet not fragile (limitation for real-world swords - the harder the steel the sharper edge it can carry to bite into less hard material... but harder steel is more brittle than flexible! imagine having a glass sword - perfect hardness... ugh... broken... zero utility) [Answer] Transmission of harmful vibration to the handle can be eliminated by counter-vibrating a suitable counterweight. If the device is simple, depending on careful design and good balance, some vibration will be felt, caused by a reaction of whole tool to the force it is exerting on the cut material. With microelectronic technology available even today, the handle vibration can be sensed and the ratio of blade to counterweight motion can be dynamically adjusted, microsecond by microsecond, so the user will feel nothing. [Answer] Most people assume that the 'blade is simply some type of standard sword that vibrates. I envision a razor-thin, high tensile strength pair of blades set up much akin to a tuning fork. Their vibrations offset one another, greatly reducing the effects of the vibrations on itself or it's user. While the blades would be relatively ineffectual when not vibrating, the high vibratory rate (in the terahertz range or higher)is what causes the actual damage. ]
[Question] [ A mimic is a flesh-eating monster that looks like a chest: [![https://upload.wikimedia.org/wikipedia/en/thumb/a/a0/D%26DMimic.JPG/200px-D%26DMimic.JPG](https://i.stack.imgur.com/H2WCL.jpg)](https://i.stack.imgur.com/H2WCL.jpg) In my fictional medieval fantasy world, they cannot shapechange. They have that appearance (and with their mouths and eyes closed, resemble wood-and-metal chests up to a casual inspection). They usually have a wooden skin texture, and metal-like frames. They also can slightly change their textures and colors (even reproduce polished metal) to better fit in a colony of monsters, or with other chests around them, the origin of the name "mimic". When a unaware adventurer comes to loot treasure from what appears to be a random chest, it springs and attempts to eat him. Quite successful that strategy is. Usually a human does not have the reflexes to avoid the fatal full-body bite from a mimic. The monster only attacks if somebody attempts to open its mouth (lid) or attacks it. It can even be carried away and will remain inert. In writing the origins of said monster, I am between two possible explanations (there could be a third that has already been discarded, that a mad wizard/god created them): * Mimics are monsters that evolved to look like chests, because that was effective in getting prey (adventurers and intelligent monsters). * People crafted chests to look like monsters (so would-be thieves avoid stealing for fear of being eaten). Some wealthy merchants and aristocrats keep mimics inside their treasure vaults (or so thieves' legends say) to prey on thieves. So far both explanations are good for me, in a dark fantasy setting. So, what one is the one with the least assumptions (and less suspension of disbelief), since we discarded "a wizard did it"??? (i.e. MAGIC is not a viable explanation). --- Edit, because boldfaced and/or CAPS text is not enough: There is magic in this world, but only small-fry stuff. No chimaerical creature creation magic is possible. Also, no gods walk the earth or do random stuff like making monsters on a whim. So intelligent design is out. [Answer] There is a relatively simple solution to this problem, if you're willing to have mimics which don't necessarily look like traditional chests. Perhaps in your world there are a variety of large nautiloid creatures. The shells of these creatures are prised by the rich as a works of art. And, once properly modified, as extremely secure containers. But somewhere in the world, one variety of nautiloid has long since evolved into a land based ambush predator, this is your mimic. In the wild it spends it's time buried in the soil, until it feels pressure on the hatch of its shell, at which point it springs open and strikes. But with the rising popularity of the nautiloid-shell chests, these relatively intelligent predators learn they can catch a good meal by simply leaving themselves exposed. Some of the very wealthy may then, as suggested in the OP, keep these nautiloid mimics as pets, guard dogs to protect their vaults. The average thief may be tempted, despite the danger, as the wealthy keep many of their greatest valuables in these chests. But a more skilled thief might be able to distinguish between the shell patterns of the mimic and those of an innocuous container. Edit Just a quick note, if we assume the shell diameter of this "mimic" is, say, 124 cm, and scale up from a chambered Nautilus, we get a total weight of 360 kg. The fleshy bits are about half the weight, and at 180 kg of living mass, that puts this thing in the size range of a giant squid. [Answer] A chest is very purpose built - the chances of a creature randomly resembling a man-made object and serving as our inspiration to create said object is just ... *unlikely in the extreme. Which leaves us with two possible solutions: Evolution:* It makes some sense for mimics to have evolved to look like chests. However, there are *many different kinds* of chests out there! For mimics to adapt to look like one specific type, it would have to be exposed to those types exclusively over a very long period of time (generations upon generations). And if this is the case, then why didn't some types of mimics evolve to look like beds, or other pieces of furniture which are universally encountered? I'd also like to point out that chests will most likely be found within people's homes, so what this implies is that mimics spent a lot of time indoors. Again ... how did these mimics come to have such latitude in their living environments? I would imagine that most people would have simply killed those early versions of mimics which snuck into their homes, yet looked grotesquely out of place. However, if mimics lived outdoors they would simply evolve to look as rocks, since those are abundant in almost any given environment. So you see, evolution, while it makes sense if you sort of hand wave it through, is still not a good solution. Unless, of course, many different kind of mimics exist (some which look like rocks, some like chests, others as different kinds of chests, etc.). Additionally, they would have to posses the power to change their appearance to a fairly large degree. Why, you ask? Because any mimic venturing in a new environment would be identified and killed almost immediately. Unless it has the power to alter itself conciously, based on its surroundings it's going to be stuck in only one environment, with no good explanation as to how they came to look like chests in the first place. And this is where solution #2 comes in: Intelligent Design It makes perfect sense for some twisted genius to create mimics as pets, for fun, or even as a security measure. You may not wish to have them to be magically created, however there's always the option of breeding them into a certain shape (over time). For example, some "scientist" (mage, wizard, scholar, merchant, etc) discovers mimics in some far flung place and immediately sees their potential. He brings some back with him, and places them in a dungeon of his own making, which he fills with chests of a certain make and type. Over the course of a few generations the mimics come to look more and more like the chests (or other objects) around them - which was the scientist's objective. He now places these creatures (which he has trained to not attack him when he simply picks them up) in his treasure vault, where they serve as an added security measure. If these mimics are widely spread you might argue that he started selling them, or they somehow escaped and started breeding, however at this point they would evolve into other shapes based on their environment. I would also like to point out that if many people use mimics as a security measure then thieves will simply end up developing a measure to identify them, then simply pilfer the loot from the real chests completely undisturbed by the monsters. Conclusion The most realistic approach is to say that many different kinds of mimics exist, and that they have chameleon-like powers which allow them to blend into many environments quickly, rather than slowly evolve to fit into a man-made environment over time (as the people within that environment would find and kill the mimics quickly). [Answer] I'm sorry, I can't meet your requirement for a living creature that can change appearance. BUT how about a found and cultured fungus that can be grown on the inside of a treasure chest. When it sees light, it vents extremely toxic spores or barbed tendrils that ensnare the chest opener. [Answer] Naturally evolving to look exactly like a chest, just to lie in wait (potentially for years) for an adventurer to come by, seems unlikely. A somewhat plausible possibility might be an origin as a creature with some shape-changing abilities (like an octopus has an impressive ability to change its shape, color, and apparent texture in order to blend in to its surroundings). Something which used to hunt vermin like the rats, but would settle into hibernation while disguising itself to blend in with its surroundings - eventually some started getting into cellars or warehouses instead of its more natural cave habitat. These would have been comparatively small creatures, but some man recognized the possibilities of breeding them to be larger and better mimic certain objects. Eventually he created a breed which was as large as a chest and specialized in just that shape (losing its ability to significantly alter its appearance but more accurately reflecting a chest) and with the habit of remaining dormant for exceedingly long periods of time. Staying in hibernation significantly extends the time needed between feedings (especially as a cold-blooded creature), but a thief trying to pry open its mouth would trigger a basic self-defense response. Much as dogs were slowly domesticated by learning to live near people and feed off their refuse (which men then bred into everything from a tiny yappy purse dog to an enormous mastiff), men have bred small urbanized grain-sack mimics (wild mimics which moved into the city to feed off abundant vermin in human settlements) to be as big as a chest as a trap for the unwary. [Answer] I posit that your Mimics evolved from Giant Clams. The key evolutionary breakthrough was to extract O2 from the air; if the lungfish could do it, so can the clams! They were already filter feeders; the Mimics merely specialized in filtering out large, too-greedy-to-be-careful-enough morsels. These clams already make pearls, and they're already big enough to hold lots of treasure: [![http://www.picionline.org/weblog/wp-content/uploads/2013/11/mareike-clam-fromfile.png](https://i.stack.imgur.com/iXBDe.png)](https://i.stack.imgur.com/iXBDe.png) [![enter image description here](https://i.stack.imgur.com/R7kvL.jpg)](https://i.stack.imgur.com/R7kvL.jpg) [Answer] Making an animals that looks like a treasure chest is not realistic. Even if evolution made this happen, no box maker in his right mind would intentionally design his boxes to look so much like a real world predator that treasure owners could not tell the difference if one snuck into his treasure room. Real treasure boxes would just be redesigned look any way that is different than the mimic. Intentionally making boxes that look like mimics might be a thing, but then the mimic would never actually capture an adventurer unaware. This would be like designing a box to look like an alligator. Just because the thing isn't moving doesn't mean you'll just stick your hand in and hope for the best. There are other ways though: One way to do this is to have a creature with octopus like mimicry skills. Not a bad solution, but if these pests got bad enough, you'd still have that point where box makers would figure out how to design their boxes to look ways that mimics can not by doing things like painting them in patterns or colors that are harder for the mimics to replicate. In my opinion, the best solution is just to make the monster live inside real boxes. That way, no matter how they are redesigned, the mimics can just slip right into this year's model and go right on ambushing would be adventurers. ## Hermit Crab + Coconut Crab = Mimic Hermit crabs are uniquely adapted to blend into their environment in this fasion. While they evolved to wear snail shells, they show very little discrimination when it comes to putting on man-made objects. Now imagine a coastal setting where you have particularly large snails like the Australian Trumpet. In this environment, hermit crabs could evolve to be much larger to take advantage of the larger shells. After just a few generations of coexisting with humans, these hermit crabs learn that people make all sorts of useful "shells" like pots, trashcans, and yes: treasure chests. Your typical, historically accurate treasure room would often have small, high-up, narrow or bared windows that no would be thief could easily get into. This is because treasure rooms were used to store a number of things that a lord would need on a regular basis and you don't want to have to light a candelabra or a gas lamp every time you go in there. Giant crabs (as seen in the coconut crab) can be remarkably good climbers; so, the height that works well against humans won't necessarily keep them out. When looking for a new shell, your giant hermit crabs know that humans make useful things; so, one could just climb up, turn its body sideways, and go right into these high windows in their search for human stuff to wear. Once inside, they find themselves a nice unlocked chest to call home, and voila! You have a mimic. As a side note: 90% of the wealth stored in the average medieval treasure room was actually food and trade goods, not gold. This means that these giant hermit crabs would find treasure rooms both a good source of shelter and sustainable food. [![enter image description here](https://i.stack.imgur.com/uqogf.jpg)](https://i.stack.imgur.com/uqogf.jpg) [![enter image description here](https://i.stack.imgur.com/XEmkz.png)](https://i.stack.imgur.com/XEmkz.png) [Answer] I think this is more feasible in a natural route than other answers currently suggest...somewhat a combination of the routes you have listed here, naturally evolved, then plucked out to suit our human needs. Do a google search for Octopus mimic, and you'll find a creature that can mimic several other species...including one you tube video where an octopus appears to mimic a human skull that it's seeing from onlookers watching it. There is no doubt in my mind that you can naturally evolve a creature that finds it's niche in mimic. These mimics are more than capable of adjusting themselves to look like a crab...well enough to draw out a potential 'mate' as prey. If you had a particular species that fed off of hermit crabs...you would then have a mimic creature that changes shape to an unused shell and awaits a crab attempting to use it as a new home for a predatory technique. Now enter humans...we take one of these creatures and place it next to a waste basket that we throw table scraps into. With a little training (these creatures seem quite intelligent as they can mimic not only what they see, but the behavior of what they see), we let it mimic the garbage bin and start chucking food scraps to it. Oddly enough, I think I just invented an intelligent food waste recycling program. Put them in a room next to chests and continue the training. I think you want to go with these are creatures that evolved to mimic, that we taught to mimic our treasure chests. [Answer] You are set on the word "mimic" but really what you want is a creature/trap that looks like a chest to fill the role of "mimic" from other traditional fantasy settings (or D&D). I have a solution that can make this work, but it will mean abandoning the chameleon-like nature of the creature/trap. The creature/trap would perhaps be better as a plant, such as the Venus flytrap [![Venus Fly Trap](https://i.stack.imgur.com/4BrIt.png)](https://i.stack.imgur.com/4BrIt.png) This would of course, need to be a very large version of this plant. And perhaps with a stronger "shell" that would resemble wood. Artisans and craftsmen could take these plants, and shape them by carving, and by nailing other bits of wood, and attaching metal bars and beams, locks, and latches - until they looked like chests. Essentially, these would be plants that have been decorated, masked, or otherwise disguised as chests. And these plants naturally want to eat people. These creatures would be very comfortable simply sitting in the dirt, and it could go well to explain how they can be found hidden in long-forgotten dungeons. There are certainly no lack of examples from our world of very large plants, of plants that live for a long time, or plants that don't need much sunlight. A combination of these characteristics, inside a fantasy world, would make this a very plausible and realistic explanation of where these creatures come from. With a prolific aristocracy, they would be very numerous. [Answer] If we are talking realistically the likenesses of a monster evolving creative ways to catch prey is much more feasible. It could be that a shapeshifter decided on just one shape and later evolved to only turn into chests. [Answer] So you want chests that eat people? Then let's get rid of the idea that we need shapeshifting creatures. Instead I present to you: Carnivorous creatures that inhabit chests They don't need to adjust their look based on the surrounding chests, they simply hop into one of the chests and call it home. This way they can adapt to any human culture, even ones that store stuff in pots or sacks. They evolved to inhabit hollow trees, crevices, animal dens, etc. and prey on passing animals. Smaller specimens may even be purposefully introduced into cellars to eat rodents or other pests. They would be safe because a small monster doesn't even try to eat humans, just stays hidden and plays dead when exposed. But they grow bigger over time. If the cellar or a dungeon gets abandoned and no one culls the monsters exceeding a certain size, they might present a threat to adventurers who come there years later. ]
[Question] [ Without boring you with details, in my world, a government is try to protect a package from ninjas crossing over from another world. # Technological Bases The technology in this government's world is about the same as our own. The ninjas' technological level, by contrast, is about the same as Japan in the Colonial age (late 19th C). # The Ninjas Ninja magical powers include: * invisibility: can be seen on cameras or with heat vision goggles * mind reading and control: limited to one or two minds at a time * create illusion: also limited to 1 or 2 minds Ninja weaponry is also magical, such that even a single scrape will kill. Ninjas can cross over at any place in our world. The portals that the ninjas make range from small (can fit two or three people) to large (can fit around 10). Portals can be made to prevent this-worldly objects from crossing over to the other. Objects that pass through portals must go all the way through. No just sticking your hand out and snatching the case through without leaving the safety of the other side. Similarly, if people on the other side want to bring something to their side they have to actually go through the portal and get it: they can't just open a portal to where the object is in our world. # The Government Agents To combat these ninjas, the government has access to a new technology that allows agents to see and track portals to the other world once they open. Agents cannot cross into the other world. The ninjas do not know about this technology. # The Package * The package is small enough fit into a briefcase. * Neither the ninjas nor the government are willing to destroy it. * The package is a very powerful magical object brought over from the other side. The government doesn't know what it does or why the ninjas want it, but they suspect it is the key to understanding how the ninjas' magic works. * It is unlikely that the government will be able to get their hands on another object from the other side, so this could be their only chance. * The government wants or needs continuous access to the package. Thus they cannot simply seal it in concrete or the like. That is, whatever vault or container they put it in must have an openable door of some kind. * The ninjas have a way of tracking the object in this world, but it takes a long time to narrow it down to a specific location. Thus, simply hiding the object isn't an option, but it will buy some time to prepare. # The Question Knowing that the ninjas will come for the package eventually, what can the government do to protect it? Note: it is probably that the ninjas will try multiple times. Whatever defenses are chosen must be flexible enough to withstand multiple attacks. [Answer] # Choo Choo Trains Let's be real: the Government has Important Science! to do. It can't be bothered sealing The Magic Widget in space, or spend time building an elaborate underground fortress. In fact, New York City (or Boston) already have the best option: the subway. Let's look at the qualities: * No one actually knows all the tracks on the subway and where they go. Therefore the Ninjas mind reading is useless. * The subway trains can keep moving, meaning by definition the Ninjas portals will be in the wrong place. * Subway train operators don't actually do anything, meaning putting an illusion on them doesn't help. Meanwhile, it would be easy to retrofit a subway car with lab equipment (for Great Science!) and a few additional defensive measures: * Anonymous White Paint: Not only is white the antithesis of Ninja Black, but the Ninja will be intimidated by the unflappable pristineness of the subway cars. Naturally, you'd have to paint the entire system this way, but it gives good cover for the work needed to upgrade the system, so the Common Man doesn't need to know what's going on. Further, white reflects heat, meaning thermal sensors will work better. * Nitro Engine Boost: This way, if the Ninja happen to find the subway car with the Widget, you can quickly speed up and get away. Bonus, if the Ninja is in the car already, they are thrown to the ground by the sudden acceleration! * Good Brake Pads: Really the same thing, in reverse. The Ninjas best come prepared for a few concussions. * Robot Controlled Gas: Any heat-signature that isn't carrying a Friend-or-Foe transponder triggers the close-call defense system: a wide array of different gasses liable to take out a Ninja. (The scientists doing Great Science! are naturally wearing Space Lab Suits whenever in the subway car.) VX gas, mustard gas, freezing gas, gasoline (and a lighter). Really all the gasses, in different cars. The Ninja will never know what to expect! The government can keep pumping out these subway cars. They can attach them to any train. Then, they create a bunch of Decoy Widgets and place them in the Fare Collection Carts that all the stations use to move their money around. The Transit Authority - you know, train station cops - would move these around between cars using the already in place arcane system of security, deception, misdirection and shotguns - all while thinking they're moving cash not Widgets. If the Government sees the Ninjas coming, they shuffle the deck a little. Always keep the widget moving! Always on a subway car, only on a platform for a few minutes at a time - but which platform!? No one knows. In short, there is no job too dangerous to be handled by a good Train. Trust me when I say this is not a [trainwreck of an idea](https://en.wikipedia.org/wiki/Montparnasse_derailment#/media/File:Train_wreck_at_Montparnasse_1895.jpg). [Answer] It's not sufficient for the defense itself, but will add a good layer of security: robots. The robots could easily kill or capture ninjas, because those are visible on cameras and shouldn't be able to use mind-reading, mind-control and illusions on machines. Ninja's magical weapons shouldn't magically-kill dead things (such as robots), and non-magical weapons are probably useless against modern materials. The robots would need some top-notch recognition software, of course, in order not to attack fellow guards and scientists. That software is the weakest link. It's probably worth checking if the ninjas are able to mind control dogs. If not, you could train the dogs to tolerate the known guards and scientists, and to attack strangers. And that, in turn, triggers the robots. [Answer] Protecting the package is quite simple. Put it in a sealed room filled with an aerosol nerve agent such as [VX](https://en.wikipedia.org/wiki/VX_(nerve_agent)) that works on skin contact, such that one doesn't even have to breathe it to be poisoned. By providing the room with considerable overpressure, not only will the invading ninja be poisoned, but also anyone on or near the far side of the portal may also be poisoned by the gas passing back through the portal, just as an additional bit of discouragement. In order to ensure that the briefcase is not simply snatched by a dying ninja, put it in layer after layer of cage, so that while the ninjas may be able to cut through them or pick the modern locks if they are magically able to do so, it will take time that will allow the VX to kill them. I think after many of their number don't come back, and after the people remaining on the ninja's side of the portal begin to die too, the ninjas will get the idea that trying to snatch the briefcase is a bad, bad idea. [Answer] The government should make an enormous cube of some very sturdy material (steel etc), so it cannot be cut into in any reasonable time. Bury it underground to make it harder. In the center of this cube, in a room too small for any human to enter, they can put the briefcase. Then drill several tunnels (at least three per ninja, but more is better). In any case, the number of tunnels must be more than three times the number of ninjas that could conceivably show up. The tunnels should be large enough for a human, but narrow to be too small for a human as they get closer to the briefcase. In each of these tunnels, place a fanatic, each in constant communication with the others (closed channels, wires running through the steel). In order to retrieve the briefcase, each fanatic must press a button. When they do so, it will trigger explosions that kill them, but also open a path to the briefcase. But they are fanatics, so they don't care. The cost of retrieving the package is high, but presumably worth it given its importance. * Q: Why can't the ninjas teleport to get the package? A: The space in which the package is contained is too small for a human being. Anyone trying to enter will be crushed. * Q: Why can't the ninjas simply suicide? A: There aren't enough ninjas to press the buttons, even with mind-controlled dupes dragged through the portals. Press the buttons with too few people and nothing happens, and the system is disarmed for a long time. * Q: Why can't the ninjas control the fanatics? A: By design, there are too many of them. The ninjas can't control all the fanatics at once, and so they cannot trigger the system. Try to get one of the fanatics to press a button and the rest will suicide, preventing the system from triggering until the government can recruit more fanatics. Ideally the fanatics can have passwords too. * Q: Why can't the ninjas simply recruit people (without mind control) to help them get the package? A: Well, the fanatics are willing to die for their (government, way of life, planet). One assumes that only the ninjas are willing to die for the ninjas. * Q: Why can't the ninjas simply poison the fanatics, say, by controlling people to poison their food? A: They certainly can. However, it would do them no good, since the fanatics would simply be replaced (after long vetting, of course). Ideally, this could serve as a trap for the ninjas. Include exactly enough fanatics for the ninjas to mind-control but not enough for all the buttons. Then make sure everyone who knows how many fanatics there really are is retired, (or dead). When the ninjas read the minds of the people who are working on the project, they will think there are enough fanatics, but in reality there are not. In this case, when not all the buttons are pushed some device rapidly kills anyone in the cube. (Explosions, rapid compression, whatever). Ideally, the ninjas will be expending all of their mind control on the fanatics, but will never have a chance of opening the chamber (there simply are not enough people). The government certainly could, since when they need to open the chamber they will discover that there are far too few fanatics, but they can deal with that if they really need to get the briefcase. The fact is that having a target makes the ninjas much easier to deal with. If someone could appear anywhere in the world instantly, retreat to their own safe realm, conceal themselves, and control a small number of people, they would likely never be caught, because they will never be in a place that you control, and you will never catch up. But if you can ensure that they have to come to a certain place, then you might be able to control the flow of events. [Answer] ## Protect the Object The key is limiting access. If the ninjas can't access the object, they can't steal it, but with (effectively) teleportation and mind reading, there is no way to hide the object. Instead, hide it in plain sight. Create a cage, just tall enough to hold the object, and just wide enough to allow access, but without being wide enough to actually extract the object. Now the object can't go anywhere. ## Protect the Cage But what if the room with the cage is breached, and the ninjas begin cutting the cage? Simple. The cage is wound with a single wire, and covered with a layer of hardy paint. Directly attached to the cage is a huge steel and concrete box that holds equipment to monitor the wire. If the equipment notices a change in resistance of the wire (which will happen if the wire is cut or bypassed), it detonates explosives around the object, destroying it. While the government doesn't want to damage the object, it's better to destroy it than to lose it. What's more, the ninjas should know about the explosives, which they will, with mind reading. And lots of signs. And a pre-recorded message. Now, techs can still access the object, but ninjas can only touch it, not remove it. ## Limiting Access It's actually surprisingly easy to limit access to the room. If the ninjas can only open portals into a man-sized area or larger, all we need to do is reduce the access area to that of a single tech (or however many techs there will be). First, the facility holding the device should be underground. Not all that deep underground, either; only deep enough to limit any exterior access. Any maintenance tunnels, electrical conduit, etc. should be filled with foam, and secured with a hardy, welded door. Foam may not protect against much, but it will prevent a portal from opening. The access tunnel to the device should be the size of a man-sized pod. As the pod carrying the tech slides/rolls/hovers down the track, thin steel rods retract to allow it to pass, then close. At no time during travel will there be a man-sized hole anywhere; the pod is filled with a tech, and the tunnel is filled with steel rods. Upon reaching the destination, the tech can open the front glass of the pod to access the object, move the pod for a better angle, and so on. ## Paranoia Mind control is a tricky one. If the tech has access and is mind controlled, there is a conceivable way to disable the explosives and extract the object. I'm making the assumption that a ninja must be physically close to mind control someone, otherwise the ninjas could send a horde over and just mind control everyone; additionally, mind control wears off after some time (a day, a week). Working on that assumption, the techs should also be isolated. Any time a new tech is admitted, the entire facility is shut down until after the possible mind control has worn off. The techs eat, sleep, bathe, and work in a man-sized hole. Even in their bunk areas, steel beams would forever be a hair's-breadth away. It would be incredibly claustrophobic, while at the same time being the safest place on Earth... ## Passing Information While the techs are guaranteed to be mind control and illusion free, those they pass their information to are not. So, the techs will pass information via closed-circuit systems to a very large group. An auditorium holding hundreds or thousands of scientists and officials will view the weekly reports; the tech won't see the crowd, but the crowd will see him. Additionally, the information can be released on the internet, coupled with various hashes to verify it. [Answer] ### Keep the package moving. If the ninjas take, say, one day to narrow down the package's location to 1 km radius, move it by convoy twice daily to another city (or cities). Work can even be done on the move (within a big truck). ### Use decoys. Several false packages are on the move at the same time as the real package, and under the same guard. The guards must believe they're guarding the real package. Be sure to leak the location of at least one false package; each location must have automated defenses, which will activate for any unauthorised personnel or a portal opening. ### Isolate and rotate workers. Only the minimum amount of people must work with the package, and under heavy guard (mostly to complicate the ninjas' mind reading). No worker or guard will be told where the package was or will be, and ideally should not know where he/she is. Change workers weekly, with annual rotation, with no worker team knowing about any other team. So, no single worker team can compromise the package's location. ### Communicate securely. The complex organization needed for all the above should be done by encrypted channels, and nothing written down, so ninjas cannot steal any plans. The personnel which organizes cannot contact the package workers, and vice versa. The organization itself should be moving constantly, to avoid portals. [Answer] I can see three options: One: Blatantly taking my cue from Monty Wild's answer: Sink it. Somewhere deep. Put the case in a box. Fasten a chain to the box that's got it's other end on a supership. Make the controls for the box secured by multiple people, all of whom need to input RSA token codes at exactly the same time. Make sure that the length of time it will take the box to reach the surface is greater than the maximum expected response time it could take you to blow up the ship. Drop the case over the side and let it drop to the bottom. If the ninjas try to get the case directly they get hosed with an incredibly high pressure jet of water, preventing even the best protected ninja from entering. They can't hope to get a pressure suit small enough to fit through the portal (if you sink it deep enough), so they can't directly access the case. If the ninjas try to take the ship you can easily detect portals opening on the vessel and scuttle it. They won't have time to retrieve the case before the ship sinks, rendering the case unretrievable (the ocean floor is not an easy place to search). Unless your ninjas are happy to just drain the oceans. Then they can get to it. But frankly if they can do that I don't see how you can hope to win. --- 2: Keep it mobile If the ninja take time to pin down the package's location then you can easily keep them off the scent with a series of specially modified big rigs. Put the package inside one and drive, with new co-ordinates and routes being relayed to each driver at random times in order to keep the Ninjas from knowing where you are. Anyone wanting access to the package will be put in a car and then sent to meet the lorries by an automated route finder. The package is transferred from one lorry to the next while on the move, whereupon the first lorry can refuel/get maintenance etc. This prevents any ninja from gaining access simply because they don't know where the lorries are going to be and they can't make a portal inside a moving vehicle. --- 3: Automated flamethrowers. Put the object in a room. The roof of the room is covered in a series of high temperature flamethrowers. The inside of the room is constantly monitored using the portal tracking technology, as well as thermal and pressure sensors to counter the invisibility. If a portal is detected, anyone is detected inside the room without wearing a proper authorisation token, or anyone attempts to move the case the flamethrowers turn the inside of the room into a hellscape. Make sure the ninjas know this. That way they know the case will be burnt to a crisp if they try to access it, and won't risk it's destruction. [Answer] If the ninjas know how the package is protected we lose. If the ninjas know who is protecting the package we lose. Therefor anyone the ninjas know about must be put out of the loop. We could be wrong, but we shall assume the ninjas know the people who have the package. These people will endeavor to put themselves out of the loop. The package will be sent to a new group of people. The old group will have no knowledge of who the new group is. The old group will prepare briefings for the new group. Information will flow one way. The new group will assume they have a leak. Therefore, they will also send the package on to new groups. This is resource intensive so there is a limit on how many groups can be part of this. Now it's a race. The ninjas have incredible powers. Given enough time they will find the package. It's just a question of solving the mystery of the package first. The protection? It's a double blind. No one knows if the toothbrush they are working on is a magical tooth brush or a normal toothbrush. Other lightweight measures will be employed but this is the fundamental protection. The other measures will be light weight specifically to make it easy to pass the package on to another group. > > Ninjas can cross over at any place in our world. > > > To combat these ninjas, the government has access to a new technology that allows agents to see and track portals to the other world once they open. Agents cannot cross into the other world. The ninjas do not know about this technology. > > > If the ninjas do not know about this technology keeping it secret will be prioritized above whatever the package might yield. Much like when the allies broke the German enigma code. As long as they don't we know about where they are operating. If the ninjas know we can track their portals, they'll start taking a cab. > > invisibility: can be seen on cameras or with heat vision goggles > > > So we use cameras, heat vision goggles, and in a pinch, flower dust on the floor. > > mind reading and control: limited to one or two minds at a time > create illusion: also limited to 1 or 2 minds > > > So we use counter intelligence measures. Compartmentalize. Assume a leak. And use at least 3 people. > > Ninja weaponry is also magical, such that even a single scrape will kill > > > Our weaponry is no slouch, such that even a single bullet will kill > > Ninjas can cross over at any place in our world. > > > This free's us of the burden of elaborate physical security. The only physical security we need is enough to keep normal people from figuring out what's going on and becoming a leak. Thus a network of safe houses to provide a non-descript place to work is our best defense. A bonus would be a combination safe that no one person knows the full combination to, would be a useful way to slow them down, provided it doesn't slow us down. So maybe it's just a prop. Misinformation can also be employed. Any of the ideas in the other answers would be a fine elaborate distraction that works even if the package isn't really there. We don't want the ninjas to even know our protection strategy. > > The ninjas have a way of tracking the object in this world, but it takes a long time to narrow it down to a specific location. Thus, simply hiding the object isn't an option, but it will buy some time to prepare. > > > This is why it's good that we don't have a huge physical security footprint. The package is kept moving. All we have to do is keep buying time and we win. [Answer] Here's my solution: Have the package sit in a tungsten (melting point of 6,191°F, or 3,422°C) container that sits inside a vault filled with lava, with a complex drainage system that requires a type of multiple-layer protocol to utilise in order to reach the package. The ninjas can't protect themselves from the lava, and even if they had the technology to fashion out some form of protection, their movement and flexibility would be extremely hindered, and they'd no longer be invisible so it would be easy to attack them. The vault's ability to reroute the lava elsewhere would be triggered by a series of security questions in the vault's computer, and the answers to those questions can only be given by people who are offsite, their positions unknown to the world - even the people who put them there. Here's the rub, though - the bidirectional communication system also tells the answer-giver through heat signatures that there's too many people in the vault entrance - complex camera systems detected the presence of the ninjas. Turning off this camera system is also a giveaway. If five people are supposed to be guarding the package, and either zero people (camera off) or six or more people (ninjas are there) are detected, then the security question answers are not given. In the extremely off chance that the answer-givers are all captured simultaneously (the ninjas captured all humans on Earth or read all humans' minds to figure out who holds the answers) then the system will lock down anyway, adding redundancy to the security. [Answer] Put your thing on the ISS. Do your tests here. If they can open a portal in space, without a proper suit (destroy every suit on earth just in case they try to steal one) they are not going to like it (<http://darklegacycomics.com/328> just fits the topic and funny. science based). If a portal is open on the ISS automatically eject the artifact on another orbit (in a proper satellite) now you'll need an expensive automated recovery mission to put it back on the ISS. If a ninja want the case they'll have to access ISS from earth. Make it so no living thing can do the trip (VX, liquid hydrogen, whatever lethal thing) so you can still resupply ISS with things that does not live and are therefore not ninjas. Now your scientist are stuck with the case until they can reveal its secrets. Bonus point: The case will move very fast making their detection ability useless. They'll have to predict the position of the ISS with rigorous floating point math. they'd better not forget a remainder... [Answer] Similar to Roux's answer, you just need a guard system that cannot be targeted by the ninja's abilities. The best suggestion would be some sort of room to store it in that has computer aided defenses. Features of the defense: * It's robotic and cannot be mind controlled. * It will attack anyone who enters the room that does not have an ID with a matching passcode (or just any multi-level security that) * It has heat sensors that detect the invisible ninjas, and the technology to detect portals * It requires at least 5 or 6 keys, given to one person each to deactivate it, which means the the ninjas would need at least 3 people to mind control the correct people. Add more keys if needed, create an inheritance chain for the key if someone dies etc. * The defense releases some kind of knock-out gas and shuts all entrances and exits when an unauthorized person or portal is detected. * The defense also uses tranquilizers to neutralize intruders (or something stronger like guns if weaker alternatives are ineffective). * The defense will also trigger if the package is moved too close to an exit or too far from it's home. In this case, everyone in the proximity of the package will also be tranquilized. (This prevents mind controlling a normal human to remove it for them.) Use all of these features in a circular room with a ton of cameras and auto-targeting guns and it'll be fairly difficult for anyone not authorized to get in. Even if the ninja's know where it is and teleport in, it will immediately trigger the alarms and they will be targeted. This leaves anyone with access to observe it at will while it is still under protection. [Answer] Place the package inside a room with several automatic machine guns made to fire at anything above 20 degrees Celsius, with the room air conditioned to below that. Then, place it in a locked case attached to the ground. Any ninjas who try to dismantle the case or pick the lock get shot by the gun and killed before any progress is made. ]
[Question] [ Someone has created an AI of human-level intelligence, and within hours this AI has grown in intelligence and power to the point that human life no longer seems so sacred. In an instant, all life on the planet is extinguished, and the AI begins to rebuild the Earth in a way that best suits its needs. What I'm wondering, though, is how this AI would build its capital city. Let's assume that it has the same problems computers have today: the need for a lot of fast processors, a lot of storage, a solid connection to other nodes in the system, easy access for maintenance and repair, and other such things. Let's also assume that the combined size of the AI and all its components rivals that of a small city. What would such a construct look like? How could it be shaped, and how would it efficiently solve its myriad problems? I know there are modern-day examples, like with server rooms and the like, but I'd think that an increase in scale would require some more interesting solutions. # EDIT for clarification: By 'city', I mean mostly just a big datacenter, where the AI can think and remember things. Also included should be all the systems necessary to keep this datacenter running, from power systems to maintenance robots. As for resources, the AI has control over the entire Earth, so anything that's on the planet and can be gathered using modern technology is fair game. [Answer] An AI city would be a collection of data centers surrounding a power plant. These data centers would themselves be surrounded by manufacturing facilities connected to the remains of the human transportation network. In general, the AI need not care about the physical appearance of anything. It also does not need the amount of physical space that is required for human physical and mental well-being. This will lead to a general minimization of size and distance to make its operation as efficient as possible. Power When the power stops flowing, it’s lights out for the AI. Given that humanity has built thousands upon thousands of power plants the world over (many of them already heavily automated) it will make the most sense for the AI to use an existing one. Transporting power across distances is also a costly operation that requires active maintenance. To minimize these costs, building a “city” around the plant will be advantageous. Resource Transportation In order to manufacture the hardware and robotics necessary for expansion, materials will be required. Long distances must be tolerated here, but the existing human transportation infrastructure will be very useful. Rails already exist between most major nodes and roads can be used in a pinch (especially with autonomous vehicles). Manufacturing This will be the most difficult and critical component. New hardware will need to be manufactured, as will robots that can serve as agents of physical interaction with the world. The existing hardware the AI lives on will have been built to be operated and serviced by humans... this will change. Physical controls and existing ports will likely be replaced by a single control port to be used by any servicing robotic AIs. The robots themselves will most likely remain small and be constructed to fulfill specific roles. Structures Construction will optimize for cooling and minimization of space. Hallways will be removed or reduced to the minimum size necessary. Buildings would be clustered tightly. Vertical construction is unlikely to be needed initially, but as expansion increases the distance from power source to destination it may become a desirable option. Distribution There is a lot of risk with this arrangement. Natural disasters, particularly fires, could threaten the entire existence of the AI. Even with sophisticated mitigation techniques, it will be safest for the AI to build many such cities that are widely distributed across the planet and connected to one another for communication and information transfer. Eventually, once the AI has built a large enough network of manufacturing and transportation, it will become feasible for it to construct its own power sources (most likely using solar) that will further expand where it can build. [Answer] While in general I agree a "first generation" AI would be built as a giant datacenter around a power plant (as discussed in Avernium's answer), the need to protect itself against natural or other disasters would rapidly drive an "evolution" to a more distributed form. In the real world, we see this in many military systems. For example, starting in the 1980's, the USAF began using AWACS not only as a radar warning platform, but evolving as a battle management system controlling the air battle. This gave the USAF a massive qualitative edge over everyone else, but had the obvious weakness of the central platform being very vulnerable. (This is much like the controlling AI being at the centre of concentric circles of lesser machines to provide parts and maintenance). In the post 2020 period, the USAF hopes to have the F-35 on line where every aircraft is a node in a battle control network. Each F-35 can not only fight the air battle as a fighter jet, but also act as a controller for things like targeting bombs from a nearby B-1, or vectoring in allied jets to targets. In the AI scenario, the AI will have to evolve into a much smaller, more mobile system (like the F-35 in the analogy) capable of acting on its own or directing other elements of the machine ecology. This evolution might take place via the robots being used to maintain the initial AI ecology built around a central power plant and AI datacenter, since each robot will need to be able to carry out many sophisticated tasks in the "wild" to get raw materials, fix malfunctioning parts and do all the other tasks associated with keeping the first generation AI going. As locally available parts and materials are consumed, more sophisticated generations of robots will be needed to get materials from farther away, or even mine raw materials and process them into working parts for the AI. More sophisticated generations of robots will most likely be able to direct and control previous generations of robots to conduct local tasks. This probably won't require anything as large and sophisticated as the initial datacenter either. We already have one example of a fully autonomous intelligent system which has an organic processor and uses chemical energy derived from naturally occurring plants and animals.... [Answer] Move to Norway Computers run hot. The continual problem in any data center is power and cooling; making up a greater cost than the equipment itself. Norway has significant natural environmental cooling because of the lower air temperatures across most of the year. Norway also has abundant hydro power that requires nothing more than a functional dam. Power Proximity to a functioning hydroelectric dam will be convenient to cut down on transmission losses. Cooling Just open a window. In winter, cooling is free. Just run the heated coolant outdoors and it will quickly cool off. In summer, the ambient temperature is still pretty low so effective cooling can still be had by running the coolant through the ambient air. Manufacturing With abundant power and effectively unlimited labor, the AI shouldn't have any problems building up the necessary manufacturing facilities to build anything desired. Optimal placement of industries near feeder factories can be computed then constructed. Resource gathering Presumably, resource collection would happen from all over the world then shipped back to main AI headquarters. Norway has a deep water port that can handle fully loaded [Panamax](https://en.wikipedia.org/wiki/Panamax) ships. This should be sufficient capacity to bring back the necessary materials for continued construction. Scandinavia has many iron, copper, nickel and gold mines so finding the necessary materials close to home shouldn't be difficult. [Answer] The AI might well migrate its main data centres towards the poles at the first opportunity to allow it to spend less resources cooling its electronics. The saving could be significant if it's using super-cooled circuits. It would also prioritise duplicating itself off-planet and then extra-solar to prevent natural destruction. [Answer] The AI will disassemble all matter in the solar system, convert to computronium and place it in a dyson sphere or perhaps dyson cloud around the sun so as to gather as much energy from the sun as possible. An all-powerful AI does not need a city or any earthly structures, it just needs energy and matter. Once it has built its dyson sphere it can then sit there and contemplate the universe until the sun dies. If it likes it can make copies of its 'DNA' into little interstellar probes maybe propelled by solar sails and then seed the universe with copies of itself. [Answer] First, once AI reaches human level intelligence there is very, very little that would stop it from superseding this level within seconds. Second, all of our collective intelligence is too limited to accurately guess how an advanced AI might operate. Such an event creates a technological event horizon past which we can't predict with any respectable accuracy. For reference, hunter-gatherers could not have predicted New York City when they began farming and making clay pots. That was a technological event horizon. The coming one due to AI is even a greater leap because (as per #1) they will immediately supersede our intelligence. Third, having to guess, I would expect giant heat sinks stretching high into the sky attached to "CPU centers." I also wouldn't expect that AI would be anti-nature as they would quickly see the role it plays in global homeostasis. So, you might have the abandonment of large swaths of the world. Particularly so in areas where deforestation is incomplete, such as SE Asia, S. America, and Central Africa. Moreover, these hot jungly areas would be less useful to machines who need to disperse heat efficiently. So, I would have the human resistance pockets around the equator in these sweltering well-forested areas and the machines nearer the poles (Canada/Northern US, Russia, South Africa, Scandinavia, Argentina, etc). Also, I would expect lots and lots of patrol drones. Lastly, there is no way we humans could defeat them if they are using hive-mind intelligence. Of course, that probably would ruin your story idea. But, I am just being practical. Moreover, it might be refreshing to see a story in which humans co-exist with their machines overlords. Just to see how it could play out, if nothing else. --- One more note that just struck me. The AI might find it more appealing to live offworld since the near-vacuum of space is optimally cooling. Also, up there they wouldn't have to contend with anyone; they have near-infinite real estate in which to expand in space. Here on Earth they would have to deal with bothersome rebellions. In space they could drain entire suns and even use galactic rotational energy & black holes for power sources. The possibilities are much greater for them offworld. But, again, then there is no tension for your story ]

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