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[Question] [ Spacecrafts that harvest ice are not out of the ordinary, there’s even research being conducted about steam powered spacecrafts (steampunk spaceships anyone??). But I want to engineer a ship that uses water in ALL its shapes and forms for power, not just for propulsion. With futuristic tech available like a completed fusion reactor how would this hydro powered ship make the most out of the available water including its components? **I’d like to know more about the cycle of water in the ship so I can better depict the inner workings of the spacecraft. It’ll be interesting to see a complex water cycle in a spaceship.** Edit: The ship is designed for long lasting exploration and will most likely carry passengers, or can be modified to do so. Core elements of the ship include the fusion reactor, cooling systems, turbines, a hydroponic or vertical farm and the ships electronics like the autopilot and batteries. Thanks to electrolysis hydrogen and oxygen are also available to make the most of the resource. Additional water is harvested from commets and debris but the ship should be able to recycle its water. Water circulates throughout the ship and should have as many uses as possible. [Answer] Just your everyday fusion-powered ion rocket. Harvest the water/ice, extract the hydrogen through electrolysis, then fuse the hydrogen in your fusion reactor to create copious amounts of energy. The remaining oxygen could be used onboard, or expelled through the ion propulsion system. Use any excess water for cooling (a big problem with nuclear reactors), then expel the steam for additional thrust. Honestly, you probably have little need to capture additional water for your crew, UNLESS your crew is growing in number during travel. Otherwise, just keep it in a completely separate system from the power system. Edit: OP updated post to emphasize a desire for complexity. This isn't typically good engineering practice, but can make for good storytelling. In that case, in addition to the above schema for propulsion and power generation, consider the following "water cycle": 1. Harvest water from environment. (If ice, wait for it to melt onboard, cooling the ship.) 2. Purify water. Put it in a "cool pure water" tank. 3. Separate some of the cool pure water into hydrogen and oxygen, using the hydrogen for fusion as outlined above and the oxygen for ion propulsion, as outlined above. (Oxygen is not the most efficient ion to expel (too light), but if you have an excess, you might as well use it. The helium produced in fusion would be even worse, but could be used similarly. Using these eliminates the need to carry additional ions to expel.) 4. Run more of the cool pure water past the nuclear reactor, turning it to steam. (This will also cool the reactor, preventing overheating.) 5. Use steam to run turbines, generating electric power. Store the steam temporarily in a "pure steam tank." 6. Cool some of the steam into hot pure water in a cooling chamber. (Structure: A strong tank with cool water running in pipes through it. The warmed coolant water will run out to thin fractal panels on the outside of the spaceship, where they will emit black-body radiation into space, thus cooling the coolant again.) 7. Further cool any unused hot pure water back into cold pure water, returning it to the "cold pure water". **Filtering:** So now, in addition to electricity and thrust, we have sources of steam, hot pure water, and cool pure water, which any equipment, system, or person on board can tap into. These provide the sources for the hydroponic farms, everyday plumbing, steam hammers, cleaning, etc. When the water gets dirty, it's purified and added back into the cool pure water tank. Of course, these filters will need to be cleaned with water, so there will (unfortunately) always be waste water. The cool waste water should be heated by the ship's cooling system (heat transfer), then to steam by the reactor, and expelled out the back and sides of the ship as high-impulse thrust (very good for turning quickly). This, together with the constant conversion of hydrogen to helium in the reactor, is why the spacecraft must keep harvesting water. **Cooling:** As mentioned above, radiative cooling is a good bet for general cooling. Pump cool pure water through the ship, gathering heat, then through the radiative cooling fins (think metal ferns with water running through the veins). As the fins emit black-body radiation into space, the water will cool again, and heat will leave the ship. If there is excess waste water, additional cooling can be attained by heating it to steam and expelling it for thrust, as mentioned above. [Answer] Behold: the nightmarish abomination known as [the nuclear saltwater rocket](https://www.youtube.com/watch?v=cvZjhWE-3zM). Also, have [a Robert Zubrin paper on it](http://path-2.narod.ru/design/base_e/nswr.pdf). [Salts](https://en.wikipedia.org/wiki/Salt_(chemistry)) of nuclear fuels are mixed into water, which is then run through an open-cycle reactor (i.e. exposed to the outside, as opposed to self-contained like existing reactors) and shot out for thrust. It is incredibly radioactive, and you don't want to use it near anything with a biosphere or potentially hydro/atmosphere, but water is a pretty common thing in the universe, as opposed to, say, methane. Also, if you want water to be used in as many systems as possible, fill the habitation spaces with it. It lets whatever crew there are survive acceleration much better than if said spaces were filled with air, IIRC, and it's much better at blocking radiation. [Answer] **Microwave rockets** The first point is that technology is simple to operate and maintain which is important if you are millions of miles from home. Water is used as the reaction mass and a compact, sealed nuclear reactor (molten salt or other design) provides electrical power, although solar cells could be used instead for missions out to about as far as the asteroid belt and still be relatively efficient. Water is pumped into a 'reaction' chamber lined with very powerful high efficiency microwave emitters (both aerials or masers would work). The water is instantly ionized and expelled out the rear of the ship to produce thrust. In theory the ISP is about twice that of the best available chemical rocket fuel. The best bit though is that while water is an excellent fuel for such a rocket in theory it can use a wide range of fuels (like methane). In fact virtually any common compound that can be extracted from mined ice could be liquefied and pumped into the ships fuel tanks on the proviso that the masers/aerials are designed to be tunable to the absorption frequency of the compund involved. Again this should be a relatively simple engineering problem since in the real world both devices can tuned to different frequencies. [Answer] How about a black hole powered ship? It is an insanely complex system of ridiculously small black holes doing total conversion, exotic matter batteries, anti-matter thrusters, fusion reactors, and steam engines that step down temperature from the hellscape near the black hole. Steam, water, helium, oxygen and hydrogen come out of the huge, nearly black box engine block, and ice and water are fed in. The front of the ship is an iceberg, which is used as both shielding and fuel. The steam turbines dump heat into it, melt it, and pump the resulting water back into the "water tank" between the habitable area and the (ridiculously radioactive) engine core. The engine core consumes the water tank. The engine does atomic chemistry, so various elements can be provided by it. It is somewhat expensive, as stable isotopes are not always dominant in what it produces. The Carbon cycle is key; removing CO2 and extracting the carbon is high value. O2 is less useful, as it isn't good fusion fuel. So this ship has a huge iceberg suspended over a habitat, which is on top of an ocean. Under the ocean is a huge engine reactor block consuming water and doing exotic physics to propel the starship between solar systems. Steam tubes come out from the ground, and the people in the ship consume it; this melts the forward iceberg (from the bottom), which replenishes the ocean, which the engine drinks. In the habitat, the near-unlimited steam is used to power the needs of the people there. It is a nice medium-density power source - not so crazy that it is fatal for the crew. More exotic deliveries can be asked for to the ship's computer (like "we need more iron") and are delivered at much slower rates. ]
[Question] [ So as most of you probably know, [cows don't produce milk all year round for no reason](https://www.simply-live-consciously.com/english/food-livestock-products/cows-and-their-milk/), [they need to be pregnant](http://www.veganpeace.com/animal_cruelty/dairy.htm) and then you gotta do something with the calves… Now in my story that has an ecosystem pretty much based on what you would find in the late Eocene on Earth, I was hoping to have some kind of milk-producing domesticated animal. Now my question is: would it be possible, through evolution/voluntary selection during domestication, to make it so a mammal would produce milk all the time without needing to be impregnated every year or so? [Answer] Producing milk takes energy. Gathering energy from food is never easy in nature, so every organism will be wise in spending it. Therefore no organism is going to naturally produce a steady flow of milk if it doesn't serve some purpose which can have a higher return on investment. The only way to have this forced via selective breeding would be to have some pathological condition, in which a cow or other animal produces milk continuously and to select for a breed which has this pathology as a genetic trait, or alternatively to find a way to induce this pathology at will. [Answer] **Yes. You are such an animal.** Human females will make milk for as long as milk is withdrawn from the breasts. At the farmers market 2 weeks ago I bought jam from a woman who appeared to be nursing a 3 year old. Back in the old days, a woman hired as a wet nurse could successively nurse child after child. <https://en.wikipedia.org/wiki/Wet_nurse> > > Dr Gabrielle Palmer[8] states: There is no medical reason why women > should not lactate indefinitely or feed more than one child > simultaneously (known as 'tandem feeding')... some women could > theoretically be able to feed up to five babies. > > > It is an excellent adaptation for a social animal such as ourselves - if a mother dies or is too sick to nurse, or is simply not available, other women in her social group can nurse the child. [Answer] You could give them a mechanism like some goats. Something that occasionally occurs in goats is once they have given birth once they will keep producing milk for their entire lives as long as they are milked every day. This is not unique to goats and pops up in several mammal groups, especially social species. If they are not milked for a few days they quickly stop producing, but this means you can keep milking them for the rest of their lives as long as you, well, keep milking them. Really you are chasing a non-issue however, most of the time you eat the old ones and raise the newborns into productive livestock. keep in mind you are talking about a year or more between births and cows for instance can be impregnated at 13 months old. You are going th be eating most of the male offspring anyway, since they will not be producing milk. ]
[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/141539/edit). Closed 4 years ago. [Improve this question](/posts/141539/edit) A gun can bring destruction but at the same time save lives, both curse and magic belongs to different system and operates independently. Curse requires strong feeling such as suffering pain while magic usually needs tranquility and serenity, however both draws energy from a common source which permeate throughout the universe. Magic can be used to bring harm when misused or even abused, but curse regardless of modus operandi is deemed as an act of cruelty and often frowned upon by the community. **If the only distinction is the state of emotion while the spell took form, why only curse is forbidden?** A good analogy is matter and it's anti-matter, they are very similar but have opposite charge, simply throwing a tantrum cannot manifest curse unless it resonate together with the frequency of the target. [Answer] When you are angry you can only "curse" and therefore only bring destruction - you are angry after all. when you are relaxed you can do anything because you can rationally think about your options and your goals. "Curse" is therefore simply a name for "casting magic while in a negative state of mind" and as a negative state of mind leads to destructive magic this is deemed illegal. It's just semantics according to your definitions, therefore only "curses" are forbidden because that is equivalent to saying "you were out of control while using a very, very powerful tool". It's like drunk driving or something similarly reckless. If you accidentally harm someone with normal use of magic it's just that - an *accident*. You didn't *plan* to do something dangerous. [Answer] I would argue that the opposite of a [curse](https://en.wikipedia.org/wiki/Curse) is really a blessing. A curse is always intended to do harm to the target, but a blessing is always intended to benefit the target. The caster of a curse would not necessarily have to be angry. Jealousy or greed would work just as well as a motive to place a curse on somebody. Black magic may come from a dark or bad place, but could potentially be used for good. All curses may be black magic, but not all black magic is a curse. There are also other scenarios like granting immortality, which depending on your point of view can be a blessing or a curse. [Answer] **You can't fuel your magic with negative emotions without it changing you as well.** So, the Unforgivable Curses in Harry Potter follow this kind of logic. After Harry casts a Cruciatus Curse fueled by righteous anger, it has a neglegible effect on Bellatrix Lestrange. > > ‘Never used an Unforgivable Curse before, have you, boy?’ she yelled. She had abandoned her baby voice now. ‘You need to mean them, Potter! You need to really want to cause pain – to enjoy it - righteous anger won’t hurt me for long – I’ll show you how it is done, shall I? I’ll give you a lesson –’ > > > The key here is that it's not just anger that drives the curse, but the cruelty as well. That level of hatred and cruelty inevitably corrupt the person trying to harness it. If you don't truly feel it, you can't harness it, but if you truly feel it, it begins to take hold of your life until it consumes you. This is also why the Sith form Star Wars appear to grow so powerful so quickly. > > Luke: Vader... Is the dark side stronger? > > > Yoda: No, no, no. Quicker, easier, more seductive. > > > Because the use of curse magic reinforces the cruelty of the user, it becomes easier and easier to do, making the user very powerful but also sealing them off from the good things in the world. It's pretty easy to imagine why a society would be against that. You can only handle so many dark wizards before you start taking steps to prevent them from being created. It's the same logic our society uses with dogs. If a dog bites someone, more often than not it's euthanized, not because of the bite itself, most are superficial damage at best. It's because when the dog finds itself in a similar situation again the dog realizes *that option worked before, so it's clearly on the table*. [Answer] I deny the hypothesis. Sometimes a curse is the only resort for someone who is tormented by another, and who cannot get justice in any other way. The deck is stacked against them, the laws favor the powerful, and the only way they can get justice is by the curse. This, of course, is well known by those in power. It is not in the interests of the powerful to let just anyone cast a curse. Of course curses are frowned on by the community of those in power. "Look at the scum who use them!", they say to each other. Thus the prohibition. If those in power allowed just anyone to cast a curse, they would have a populist revolution on their hands in no time. [Answer] ## Propaganda Why do you think it's called something with such a strong connotation as "Curse" in the first place? Magic is tranquility and serenity like you mention. But more than that, **Magic is Order, Control and a steady strength.** "Curse," as the propagandists would have you believe, is suffering and pain. **But deeper than that, it's Chaos and Change.** Do you really need strong painful emotions when casting? Or just strong emotions in general? Just how much of what you know of "Curse" is actually true? So of course the goal of those who firmly believe in Magic, Order and Control is to outlaw anything that could shake their rule. And what could be more disruptive to them than the force of disruption itself? Chaos and Change are naturally their most dangerous enemy. So how do you prevent the populous from practicing this? Outlaw it. Make it taboo. Paint it as a sick and evil art. Of course, as any historian knows, you can't hold back Change forever. The longer you try, the more Chaos it will bring when it finally comes... [Answer] I'm sure this comparison has been drawn already, but this notion is very similar to the Light and Dark Sides of [The Force](https://en.wikipedia.org/wiki/The_Force). They are both sides of the same power that governs and intertwines among all living things, but the aspects of The Force that are seen as "The Dark Side" are heavily discouraged and, past a certain point, criminalized. The difference is that the Light Side is the side that is attributed to peace, order, and serenity, whereas the Dark Side is attributed to passion and chaos. While not inherently so, the Dark Side was seen as evil because of the penchant of its followers to sow destruction. In addition, in the words of then Supreme Chancellor Palpatine, "The Dark Side of the force is a pathway to many abilities, some considered to be unnatural", which further deepened the mistrust directed toward Dark Side practitioners. Your "curses" are similar in that they differ from "good magic" only in the nature of their source - passion as opposed to peace. That by itself isn't enough to label curses as evil, but consider the types of people who would be drawn to a more passionate form of magic. Those types are more likely to cause chaos and destruction, either accidentally as they experiment and explore, or deliberately as they seek higher forms of power. Practitioners of "good magic" would be seen as calm and noble by comparison, so they would become the standard by which all users of magic are judged. As such, there would grow to be a historical mistrust toward users of curses that penetrates deep into people's prejudices to the extent that even suggesting their use could be seen as a criminal offense. ]
[Question] [ **Closed**. This question needs to be more [focused](/help/closed-questions). It is not currently accepting answers. --- **Want to improve this question?** Update the question so it focuses on one problem only by [editing this post](/posts/138958/edit). Closed 4 years ago. [Improve this question](/posts/138958/edit) In my world a nation currently involved in a civil war between multiple warring factions is nearing an end. The man who has appeared as the victor is a blood thirsty tyrant, who continually suppresses and objects to any freedom being given to civil society. **In terms of the leadership of the country all decisions fall on a single head of state, and is almost a regression back into a system of monarchy.** However for the story to continue I require the effects of the dictatorship to have positive outcomes for the state, resulting in the unified state warring with other nations to implement their system of government, to which they have achieved substantial success. **How do I allow the leader to loosen his grip on power, resulting in social benefits to the nation, without it resulting in him being usurped?** Edit: I understand the question in this context is to broad, my apologies for the oversight on my part. In order to clarify the aspect in which I require assistance, **the question fundamentally relates to a type of governmental structure or possible oversight mechanism that could be introduced without necessarily having this result in the leader being place in a position in which he is unable to perform the same task he would, if per se he was still using his military force to hold on to absolute power.** [Answer] A good example of warlord turned dictator would be Qin Shi Huangdi the "first" Emperor of China. Through massive numbers of troops, mass produced arms, and controlling vast amounts of natural resources Qin conquered the other warring states and proclaimed the Qin dynasty. Was he benevolent, sorta. To the old guard he was a bloody tyrant that massacred thousands. To scholars he was a book burner known for burying scholars alive, but overall he was a reformer. The true strength of Qin was not his armies, but was his legal system. Qin also embarked on building campaigns expanding the road, irrigation, and canal network which had a dramatic effect on China's population. While the Qin dynasty was short lived it centralized China and led to the prosperous Han Dynasty. In this case have your dictator focus on reuniting the land and centralizing the rival states into a single government again. Big building projects also help, plus big statues. [Answer] **He is fair.** His grip need not loosen. He is ruthless. He can be brutal when it serves his purpose. His brutality is brutality with confidence - he does not over react and his measures are always proportional to the situation. He is not capricious and he is not random. He does not play favorites. He has a long term vision for his people, and this does not involve petty rivalries or enrichment of his entourage. People who want to get away with something fear him. Most people are happy to be living in a stable state, without petty warlords or crooked local politicians. People rise up in revolt because they are hungry and poor and perceive that they are being treated unfairly. They revolt not because they are hungry but because they want fair treatment. If the populace feels it is being treated fairly and they are working as a people to ameliorate the situation, they will not revolt. [Answer] ## TLDR : He doesn't want to be cruel or benevolent, he needs to be in order to stay in power This answer is inspired by the work of Bruce Bueno de Mesquita and Game theory in general. If you speak french, you can also see this [video](https://www.youtube.com/watch?v=4dxwQkrUXpY) of Science4All. Basically, your dictator will not act by ideology, or because he is "evil", but will simply do anything to stay in power. Be it kill some opponent or grant some liberty to people. Let me introduce an historical example to understand how one can be both "good" and "evil" at the same time, just to stay in power : [Leopold II](https://en.wikipedia.org/wiki/Leopold_II_of_Belgium) Leopold II was King of Belgians in the late 19th century. He was also ruler of Congo. Here some facts about his reign : In Belgium * free school * legalize labor unions * make child work illegal * instore Universal suffrage During the same time, in Congo,there was a complete military control over the population, with around 10 million deaths. Yep, the same king granted lots of liberty to one part of his kingdom, while doing atrocities on another part of his kingdom. But both way of ruling served the same purpose : keep ruling. The major danger in Belgium was a revolution by the people, so King Leopold was very benevolent to the people. In Congo, which was a colony, things were different, the army held the power. In order to keep the power, he needed to be benevolent to the soldiers, not the congolese population. Therefore, all the rubber system in Congo was made to grant power to soldiers, and make them rich, so they remained loyal, even if this had terrible consequences on the population. You can adapt his to your dicator : he needed to be brutal in order to win the war, unify the country, and suppress any counter-revolt, but once this was done, he could do more "good" things while remaining in power. [Answer] > > *Despotism is a legitimate mode of government in dealing with barbarians, provided the end be their improvement.* (John Stuart Mill, [*On Liberty*](https://en.wikipedia.org/wiki/On_Liberty), 1859, as quoted by Wikipedia *s.v.* [List of enlightened despots](https://en.wikipedia.org/w/index.php?title=List_of_enlightened_despots&oldid=877882859)) > > > *"How do I allow the leader to loosen his grip without it resulting in him being usurped, or possibly to stay in power while at the same time not altering his character entirely?"* The best way to describe the actions and accomplishments of such an enlightened absolute ruler is to model them on the real actions and policies of actual enlightened despots, who have been recognized as such by history. * [*Enlightened absolutism*](https://en.wikipedia.org/wiki/Enlightened_absolutism) is the conventional name given in history to the *"conduct and policies of European absolute monarchs during the 18th and 19th centuries who were influenced by the ideas of the Enlightenment, espousing them to enhance their power"* (Wikipedia). Everybody agrees that at least the following absolute rulers deserve the name of enlightened despots: + [Frederick the Great](https://en.wikipedia.org/wiki/Frederick_the_Great) of Prussia. > > *Considering himself "the first servant of the state", Frederick was a proponent of enlightened absolutism. He modernized the Prussian bureaucracy and civil service and pursued religious policies throughout his realm that ranged from tolerance to segregation. He reformed the judicial system and made it possible for men not of noble stock to become judges and senior bureaucrats. Frederick also encouraged immigrants of various nationalities and faiths to come to Prussia, although he enacted oppressive measures against Polish Catholic subjects in West Prussia. Frederick supported arts and philosophers he favored as well as allowing complete freedom of the press and literature.* > > > + [Catherine II "the Great" of Russia](https://en.wikipedia.org/wiki/Catherine_the_Great) > > *Catherine reformed the administration of Russian guberniyas, and many new cities and towns were founded on her orders. An admirer of Peter the Great, Catherine continued to modernise Russia along Western European lines. [...] The period of Catherine the Great's rule, the Catherinian Era, is considered the Golden Age of Russia.* > > > + [Maria Theresa](https://en.wikipedia.org/wiki/Maria_Theresa) of Austria. > > *Maria Theresa promulgated institutional, financial and educational reforms, with the assistance of Wenzel Anton of Kaunitz-Rietberg, Count Friedrich Wilhelm von Haugwitz and Gerard van Swieten. She also promoted commerce and the development of agriculture, and reorganised Austria's ramshackle military, all of which strengthened Austria's international standing.* > > > + [Napoleon Bonaparte](https://en.wikipedia.org/wiki/Napoleon_Bonaparte) and [Napoleon III](https://en.wikipedia.org/wiki/Napoleon_III) of France. > > *Napoleon's influence on the modern world brought liberal reforms to the numerous territories that he conquered and controlled, such as the Low Countries, Switzerland, and large parts of modern Italy and Germany. He implemented fundamental liberal policies in France and throughout Western Europe. His Napoleonic Code has influenced the legal systems of more than 70 nations around the world. British historian Andrew Roberts states: "The ideas that underpin our modern world—meritocracy, equality before the law, property rights, religious toleration, modern secular education, sound finances, and so on—were championed, consolidated, codified and geographically extended by Napoleon. To them he added a rational and efficient local administration, an end to rural banditry, the encouragement of science and the arts, the abolition of feudalism and the greatest codification of laws since the fall of the Roman Empire".* > > > *Napoleon III commissioned the grand reconstruction of Paris, carried out by his prefect of the Seine, Baron Haussmann. He launched similar public works projects in Marseille, Lyon and other French cities. Napoleon III modernized the French banking system, greatly expanded and consolidated the French railway system and made the French merchant marine the second largest in the world. He promoted the building of the Suez Canal and established modern agriculture, which ended famines in France and made France an agricultural exporter. Napoleon III negotiated the 1860 Cobden–Chevalier free trade agreement with Britain and similar agreements with France's other European trading partners. Social reforms included giving French workers the right to strike and the right to organize. The first women students were admitted at the Sorbonne, and women's education greatly expanded as did the list of required subjects in public schools.* > > > (All quotations come from the respective Wikipedia articles. Note that I have intentionally selected the *good* parts; those rulers were absolute despots, and beside the good they also did quite a few *bad* things. Some of them were intolerant of religious or national minorities; some were blind to the fate of the lowest strata of the society; and none of them hestitated to involve their countries in wars with uncertain odds, sometimes succesful, but sometimes with long-lasting negative effects.) Wikipedia has a [longer list of enlightened despots](https://en.wikipedia.org/wiki/List_of_enlightened_despots). Wikipedia has an [enlightened observation](https://en.wikipedia.org/wiki/List_of_enlightened_despots) on the matter of enlightened despotism: > > *Generally, dictators who serve in office for a very long period are more likely to be regarded as enlightened because they will often be forced to pay some attention to the public interest in order to remain in power and, more importantly, to be regarded as legitimate. Dictators who hold office for a brief period of time or are simply members of a rotating dictatorial elite (such as those heading some juntas) may have less charismatic authority and prove to be forgettable and are therefore often easier to demonize.* > > > [Answer] ## The Measure of a Man You have stated that your story ends with the ruthless barbarian in power, and now that he has that power you want him to be a benevolent ruler. So I am going to do a slight reframing and say the inherent question is: What kind of man does anything to gain power and then uses that power to elevate his subjects? I can see a couple of options here that focus on the backstory and personality of your tyrant. Note that I am moving away from the idea of this benevolence being caused by governmental structures. The fact is that if the ruler has absolute power and was ruthless enough to gain power, he would not hesitate to remove or subvert anything that stood in his way. It would just be another extension of his initial rise to power. ## The Dauntless Ideologue Your tyrant is a man of uncompromising ideals who is willing to do anything to remake the world into whatever he feels like it should be. In this case I would consider him being a victim of injustice caused by the previous government/system. He joins the civil war not out of a desire to rule, but a desire for *change*. He is a man that steps up to solve the problem because no one else will. Whatever kind of positive outcome comes from his rule is *intentional*. The whole point to all of his previous actions was to get a place where he could enact change and raise his people up. His actions looked ruthless and cruel to the factions that he fought against but his supporters see him as a guerilla fighter and a hero of the people. ## The Heartless Altruist This tyrant is after power and actively sought out his rule using any means necessary. Violence, assassination, blackmail, extortion. Your ruler is coldblooded and sees the people around him as little more than pieces on a game board, to be moved and used and manipulated in whichever manner provides the optimal results *for himself*. All of that said, this kind of ruler is not a cartoon villain who is Evil for Evil's Sake. Manipulating people for your own goals does not inherently mean harming them. After a brutal civil war the nation will want peace and to heal. Your tyrant will do as much as possible to facilitate this and make the common people happy as part of his plan to consolidate his power. With enough political savvy your ruler could easily purge his political enemies and spin it as him casting down the old guard and reforming the nation. Taxing the nobility or wealthiest merchants lets him raise capital to be spent on civic projects like better roads and more schools or hospitals. And if that also happens to bankrupt his political opponents and naysayers then really everyone wins. ## The Charismatic Fanatic This one is a bit simpler in terms of motivation, but also requires some assumptions about the people in the nation. This ruler is driven similar to the Ideologue but his motivation is *external* instead of coming from a personal principle. The tyrant is a true believer in a religion or other cause, and sees the civil war as a way to further that cause. He is able to rally the people using impassioned speeches quickly gains massive amounts of popular support in his bid to unite the country. His army of peasants and farmers may not have the same quality as the other factions, but quantity has a quality of its own. This is going to be a finer line to walk for what you want than the other two examples, just because it is so easy for this type of leader to be exclusionary. Our history is pretty rife with people who rode a wave of demagoguery to power and then proceeded to only make things better for the part of the population that agreed with/supported them. Depending on your exact definition of "benevolent" there is a lot of wiggle room for some group to be suppressed while the ruler's base is elevated. That kind of dynamic is really sustainable unless the suppressed group is in the minority, in which case you have more or less invented Hitler. Assuming you can get around that hurdle and not make the ruler a fantasy fascist, the rest of it comes together nicely. He is ruthless because he is serving a higher power/ideal and that always gives people an excuse. He is benevolent because that is also part of what he believes in. This leader even has something like a structure or group that can help mitigate their worst traits, since there is bound to be some church or organization already in place that will have a say in things. ## Heavy Lies the Head Your ruthless tyrant is a person and people are almost never one dimensional robots. He will have a history, personality, flaws, and a worldview which will all contribute to the actions he takes. You already know the end result, things getting better when no one would have expected that. The rest of the job is just working backwards from there and deciding exactly what kind of a man would end up in that situation. ]
[Question] [ One species has two genders, like humans, the other has three(essentially male, female, and one without breeding capabilities that first appears as a genetic quirk but quickly becomes more prominent until it is equal to the other two). It is in an advanced society with two different regions, one for each species, on opposite sides of a small planet. [Answer] **Would a society with two different species that can interbreed be viable?** Sure it's possible, by a number of processes the most obvious being [hybridisation](https://en.wikipedia.org/wiki/Hybrid_(biology)). The process by which two distinct species combine to form mostly infertile offspring (Vis-a-vis mule)- but just occasionally they are viable. > > There is evidence of hybridisation between modern humans and other > species of the genus Homo. In 2010, the Neanderthal genome project > showed that 1–4% of DNA from all people living today, apart from most > Sub-Saharan Africans, is of Neanderthal heritage. > > > But you can't expect them to be a perfect halfway house: > > Hybrids are not always intermediates between their parents....but can > show hybrid vigour, often growing larger or taller than either parent. > > > Another intriguing way would be through [chimerism:](https://en.wikipedia.org/wiki/Chimera_(genetics)) > > A woman was found to have blood containing two different blood types. > Apparently this resulted from her twin brother's cells living in her > body. > > > However it may be more obvious than this as it could occur in your creature's skin, giving a mottled blend of the two skin types you mention above by [mosaicism](https://en.wikipedia.org/wiki/Mosaic_(genetics)). Culturally, would either society accept a crossbreed? See [Nazi Eugenics](https://en.wikipedia.org/wiki/Nazi_eugenics) for an idea of what can happen. Would the prevailing cultural atitudes drive these unique creatures to the fringes, desperate, and in hiding - would they have a political voice? Allies in the general populations? Would some be driven to violence? Only you can decide. Here's further reading to fuel your immagination: <https://en.wikipedia.org/wiki/Polyploidy> <https://en.wikipedia.org/wiki/Horizontal_gene_transfer#Plants_to_animals> <https://en.wikipedia.org/wiki/Endosymbiont> [Answer] In biology a [species](https://en.wikipedia.org/wiki/Species) is defined as > > "a group of living organisms consisting of similar individuals capable > of exchanging genes or interbreeding" or > "the largest group of organisms in which any two individuals of the appropriate sexes or > mating types can produce fertile offspring, typically by sexual reproduction." > > > Therefore, if they can interbreed, they are by definition basically **not different species but only two very different looking races of the same species** i.e. variants of the same species. This does not mean that they cannot have completely different physical appearances or capabilities; as an example consider how different a chihuahua is compared to a St. Bernhard, but they are basically both dogs and can interbreed. [Answer] Short answer: Sure. Why not? Longer answer: Horses exist. Donkeys exist. Horses and Donkeys can interbreed. Do donkeys become more horselike over time? No. Why? The offspring of an inter species breeding are typically infertile, and so can’t pass on the traits of either species. They can mess with breeding patterns by ‘stealing’ potential mates, but otherwise they have no further genetic impact. If the two species can interbreed and produce fertile offspring then Alex2006’s answer applies: they are not two distinct species. You can get fuzzy on the whys and wherefores of when you choose to ‘split’ the species, but that’s mostly an arbitrary ‘because I said so’. As for the social implications of whether two sapient species can coexist peacefully without the word ‘genocide’ getting used a lot: we can’t say much. But from a biological perspective if you simply have interspecies children be infertile then your problem completely goes away. [Answer] It depends on too many variables. As alex2006 pointed out, by definition you only have *one* species. Let's call their makeup as XY and XX for the group 1, and xy and xx for group 2. Equal symbols mean female phenotype, different symbols mean male phenotype. The "third gender" could arise as a variant of [Klinefelter's syndrome](https://en.wikipedia.org/wiki/Klinefelter_syndrome) where xxy "males" do not have any impairment at all, except for sterility, very low sexual drive and androgynous appearance. A XY male and a xx female may interbreed and have Xx female or xY male children. Possibly xxY children too. What happens to Xxy, XXy and xxY children? It all depends on the exact nature and interaction of the sexual chromosomes. * the combination is immediately fatal: the foetus does not develop and you don't even get a pregnancy. To all intents and purposes, "Group B" only breeds true. An intermixing of the groups will then lead to a diminishing of the third gender group, as less of them will be born. * the combination is later fatal: the foetus is born dead or it even damages the mother, or makes it sterile or selectively sterile (for example by a mechanism akin to mother-foetus immune incompatibility); the xx mother will from now on only be fertile with pure xy males. This will easily lead to resentment and conflict. * the combination is harmful but not fatal: interbreeding has a high chance of children being born handicapped, or worse. Either group may blame this on the other. * nothing much happens: the two groups can interbreed and the "third gender" demography might change, or not. The other physical characteristics will naturally blend, and there's no biological reason for racism to develop (this still doesn't mean it couldn't). There are several other possibilities with the same, as well as wildly different, outcomes. Just for kicks, imagine that XXy children are born with some marked advantage (longer lifespan, higher intelligence...) and decide they're the new Ubermensch? [Answer] I understand "viable" in your question as "capable of long-term existence" with the biggest threat being permanent hybridization and ultimately unification into one species. [Hooded crows](https://en.wikipedia.org/wiki/Hooded_crow) and [carrion crows](https://en.wikipedia.org/wiki/Carrion_crow) are related closely enough to interbreed. Their ranges overlap, so the two species meet. For years they were thought to be subspecies of one species and hybridization to occur widely. However, it turned out it's not so. They're classified as distinct species now. What's most important for you, they **can** crossbreed, but they **choose** not to. Hybridization is rare. That's pretty much your world. The two groups were one species very long time ago. They were separated (eg by continental drift) and drifted apart, genetically. Now (thanks to technology?) they can meet again. IMHO your hybrids should be at disadvantage. In our world, hybrids usually are at disadvantage, sometimes completely sterile, sometimes just having slightly more trouble breeding. A hybrid can have an advantage **personally**, eg. combine physical strength on one side with intelligence of another. But, for the species as a whole it's **reproduction** that matters the most. Even small reproductive disadvantage is enough for purebloods to always outnumber hybrids, pushing them into outskirts and maintaining distinction between two societies. That's enough to make your society maintain status quo indefinitely, what I interpret as "viable". ]
[Question] [ # Background This world has two continents, an old and a new. The Old World developed much as ours did, and finds itself in the throes of an Industrial Revolution. Due to the nature of the oceans and winds, transportation by sail to the New World was limited and difficult. However, with the invention of screw driven, iron-hulled ships, it becomes possible for the Old World to fully impose itself on the New. Concomitant with the Industrial Revolution is a massive expansion of population, just as happened in our world. The New World is an ideal outlet for the disaffected proletariat, and soon there are many schemes to establish colonies. But the New World, although underpopulated by disease, is not completely empty. There exists in the New World a power unknown or forgotten in the Old: [Blood Magic](https://worldbuilding.stackexchange.com/questions/103703/how-does-a-blood-shaman-gain-his-power). A blood shaman kills a wild animal, and through a secret ritual gains the ability to mimic its power. An advanced blood shaman has the speed, agility, stamina, and toughness of a wild beast, while keeping the body and mind of a man. The advent of the colonists caused significant tension between the few remaining natives and the newcomers. But unlike in our world, blood magic gives the natives a chance to fight back. The key to victory was the previously little-used [Pampathere](https://en.wikipedia.org/wiki/Holmesina). Unlike the massive carapace of [*Glyptodon*](https://en.wikipedia.org/wiki/Glyptodon), a blood shaman using the Pampathere's armor still had the flexibility to move with the grace of a cougar and the power of a horse. But drawing on the power of the Pampathere's quarter-inch bony hide also made the shaman's nearly invulnerable to gunfire. # Question **How does a battalion of Napoleonic Era troops kill a blood shaman?** ### Considerations * The blood shaman has the shape and intelligence of man. But, drawing on the powers of the animals he has killed, the shaman has the mass, strength, and toughness of a bison, the agility and stalking ability of a jaguar, and the long-distance speed and stamina of a deer. * Most importantly, his skin acts as if it were a quarter inch of bone. Musket shots can penetrate, depending on the angle, but even if they do it will barely slow down a shaman with a bison's toughness. * The shaman can also call upon the best senses of the animal kingdom; a bear's smell, a wolf's hearing, a cougar's night vision, and a man's binocular, color day vision. * The shaman's enemy is a battalion of Napoleonic era troops, with all the equipment typical of that age. * The onus is on the battalion of troops to kills the shaman. The shaman wins by staying alive and conducting a guerrilla war against the colonists. He doesn't need the troops dead, per se, he can just make sure he kills a few colonists in their sleep every night to eventually persuade them to leave. [Answer] This is a tricky one. Strategically we can exterminate the animals to remove the blood shaman as a threat, but that won't stop the existing powerful shamen. Since we're specified as having just the battalion and seeking a new life we're probably also not interested in going home and begging for the real army to come down. The good news is we can still fight this. We just need the right weapons and strategies to threaten the Blood Shaman. ## Close Quarters: Nets and Bludgeons The first thing we need is to be able to fight back against the Shaman at close quarters, when he tries to assassinate our people. The most important thing for this is armour. A cuirass or full plate is best of course, but at minimum we just need, say, a leather gorget and a piece of thick metal secured over our hearts. Easy enough to improvise, and it'll make killing us off a slower task - the Shaman can't just cut our throats or stab our hearts on the fly (or at least it's going to be harder). Next, we need to stay in groups. Sleep in well guarded communal halls. Post guards in and around our people, train guard dogs, and keep large patrols. This keeps the Shaman from picking us off one by one, and means we can easily back each other up in an attack. Finally, we need weapons. We need anything that can tangle up an assailant and whatever bludgeons we can scrounge (muskets are excellent bludgeons). He's bulletproof, sure, but the traditional counter to armour is a mace. It doesn't have to do much damage, just a little. If he commits to an attack we need to gang up on him, tangling and tripping him with anything we have and wrestling him as best we can (even a bison can't overpower dozens of strong humans) while bludgeoning him with our weapons. It won't do much individually but every little bruise will weaken the Shaman - and also keep him from switching to a more agile but less tough mode, lest he *really* get his head staved in. If we gain the upper hand we can finish him off with any number of awful fates, like drowning him, smothering him, dousing him in oil and burning him, or even just bludgeoning him to death slowly. This is only easier if he switches to a tougher but even less agile mode because he can be more easily overpowered. ## Skirmish Range: Swivel Cannon and Palisade At medium ranges, the Shaman is trying to use his mobility against us, likely using spears or flaming torches to kill us and burn us while staying too far to wear him down with shot. Here better armour helps but what we really want defensively is palisades. Makeshift walls we can hide behind and can get the spears stuck in them instead. Mounted on these walls we place swivel guns - small cannons normally put onto ship decks to be used against crew and boarders. If we have lots of spares, we can bind them together into volley guns to improve our chances of landing a hit. By shooting back with these in addition to our muskets, we level the playing field a bit more - even if a small cannon can't quite kill a Shaman, it can wound them and slow them down. Worse, if the Shaman tries to close in to kill the gunners, they risk getting netted. And *then* shot with a cannon. ## Long Range: Chain Barrage Finally we'll look at long range attacks. The Blood Shaman gets an atlatl or bow or stolen rifle and tries to snipe us with stealth. There's a traditional answer to snipers: Artillery. With a battery of large cannon we can force the Shaman to run by simply shelling the entire area he's attacking from. By loading the cannons with chain shot (two half cannonballs connected by a chain, normally used to cut masts) each shot can have a sizeable area of effect, giving us a better chance to cripple the shaman and reducing how many cannons we need. It's going to be tricky to actually hit him since he's so fast, but we can still make sniping risky. If the Shaman makes a habit of sniping we can start setting up traps - simple ones, like a trou de loup or a punji trap. With a barrage of chain shot coming at the Shaman, a moment of hesitation or a slight stumble can be fatal. --- None of these tactics guarantees a kill against a powerful Blood Shaman, but they all present at least a small chance to gain the upper hand against a Shaman. And the Shaman has to win every engagement. We just have to win *once*. [Answer] Why would they fight the blood shamans? The best method to fight the natives is to pay other natives to do it for you. For that matter the best method to fight competing colonial nations is to pay the natives to do it for you. Similarly the best method to enslave the natives to be forced labor for your colonies is to pay other natives for slaves. Make alliances with nearby tribes. It is okay to deal fairly and keep your promises if it makes you happy. It makes no difference to the end result. Pay bounties for slaves, killed allies of your colonial rivals and killed soldiers of colonial rivals. You can also hire natives to work directly in the colonies. Given the economic disparity you can be generous. Very soon your colonial rivals will follow your example. This will at the same time collapse the traditional tribal societies and create a constant state of low level warfare. The combination means the natives are unlikely to even survive as a separate entity from your slaves or second class citizens. There is no need to fight them. Only real chance the natives have of fighting of a colonial power is a strong leader that unites them and is able to pursue a coherent strategy. Even then, when the strong leader dies, the natives lose. Unless the blood shamans can forge a stable political force capable of leading the natives for several generations, there individual fighting strength only means the colonial powers have access to stronger mercenaries. [Answer] **Scorched Earth campaign** The natives have home-territory advantage - make it so they don't. Set fire to the forests, plains, jungles, etc. While that won't necessarily stop the blood shamans, it will reduce or remove their ability to gain new abilities and render some of their abilities irrelevant. Stalking across a barren field where the enemy has a clear line of sight is a lot harder than stalking through a heavily-forested area. In addition to removing the natural cover that benefits the natives, it will demoralize them. Wildfires are sensory overload, even for the relatively poor senses of a human. If animal instincts are in play, the blood shamans may be unable to control their flight reflexes. **Bribery** Does the industrialized nation have its own unique wildlife? Zoos of exotic animals (and therefore new and exotic powers) could make excellent bribery material for some enterprising shamans. In return, they agree to betray or combat their former tribes. Shaman-on-shaman warfare might prove to be instrumental in turning the tide of combat. **Special Forces** Rifles were in early development during the Napoleonic era. They were more complicated and slower to shoot than muskets, but more accurate at longer range. Put military rifles in the hands of a special division populated by trophy hunters. Humans hunt everything, from squirrels to deer to bears to bison. These soldiers are tasked with hunting the Most Dangerous Game. Through teamwork, individual skills, and advanced technology, they should prove a match for blood magic. [Answer] Sheer force of Numbers. A Napoleonic-era guerrilla is unlikely to work well against small colonies of a densely populated continent. In fact, the overpopulated continent can easily increase the number of conscripts and stuff the New World with lines of barricades, watchtowers, lines of gun-fire, and explosive traps. Given the small size of the colonies, defense is relatively easy. In fact, 1. the first step is to remove woods or other sight-obstructing wild area. This provides free fields for cultivation, as well as an easily controllable ground around the dwelling. 2. the second step is to monitor the area of activity of the shaman. Place fortifications, watchtowers, palissades, concrete walls, bear-traps, and the such to prevent that the shaman walks outside of the designated area. And note that an unaware human being is as likely as a bear to fall into a bear trap. 3. the third step is to chase the shaman. Organize your voltiguers as scouts. Entrench the riflemen. Close circles loaded with explosives around the area infested by the shaman. If the shaman is sighted, shoot to create a distraction, drive him/her onto the explosive and blow him/her up. Alternatively, grape shots from cannons, or incendiary shots will do just as good. 4. Finally, controlled fire of the last portions of woods will do just as good. Either the shaman fries in the fire, or it will be driven out, shot and blasted as discussed above. **A note on bullets.** Depending on the period, several options are available including infamous [dumdum bullets](https://en.wikipedia.org/wiki/Expanding_bullet), which, together with [express rifles](https://en.wikipedia.org/wiki/Express_(weaponry)), were quite successful against bigger games. It is easy to imagine that at the first observation that conventional bullets seems ineffective against the shaman, the industrial revolution era military would resolve to science and demand more penetrating, faster and perhaps even explosive bullets to get rid of the nuisance. **A short consideration on the occupying army.** A Napoleonic era battalion is quite a dynamic definition, where the [numbers and composition change according to the specifics of the conflict at hand](https://fr.wikipedia.org/wiki/Bataillon#Rappel_historique). In any case, we are considering a group between 500 and 1000 armed men, divided into companies, and likely comprising of riflemen, grenadiers, and [voltigeurs](https://en.wikipedia.org/wiki/Voltigeur). These are most probably conscripts, who undergo standard military training, but in their normal life were probably farmers or factory workers. Finally, if we stick with the Napoleonic Era military composition, it is entirely possible that the ranking officers are a mix of high bourgeoisie and the spawn of some form of aristocracy, both of whom are likely acquainted with game hunting as a hobby. In this regard, shamans are just the game of games, i.e. the best and most fun of hobbies. I can very well envision a large number of volunteers signing up to the "special battalion X" just for the sake of hunting this mashup of all possible wild game. [Answer] Guns play just a minor role in opressing indigenous people of less developed continents. There is a number of ways that the old-worlders can defeat blood shamans. Most of these are low-blow, but honor does not win wars. ## Long term warfare - strategy These strategies cannot be put into action in the course of a battle. However, should you consider a given battle in the midst of an ongoing war, these may have already been set in place, so they may affect the shamans. ### Loss of popular support I think blood shamans are a minority among new-worlders, right? Push the natives into a hedonistic way of life. Present the masses with things such as alcohol, opium, cannabis, prostitutes, machines that make everyday easier and other such gifts. They will start thinking along the lines of *"why should we ever help the shamans, when the [wasicun](http://www.native-languages.org/iaq20.htm) grant us such amazing gifts?"* ### Diseases Syphilis. Smallpox. Enough said. ### Ecological warfare Since blood shamans derive their powers from animals, all you have to do to prevent the shaman gaining new powers, and also to prevent more shamans joining the fight, is to extinguish those animals. In our own world, the "civilized" societies are very adept at causing massive extinctions in record time. In this fictional world, in which much of the new world's power derives from flammable forests, your blood shamans would better learn how to do the rain dance at Just Dance's Superstar level. --- I believe your question is more centered around tactical combat, though. Let me finally get to that point then. ## Short term warfare - tactical combat ### *"And if guns don't solve your problem, just use bigger guns"* - TF2 Engineer It just doesn't matter how big your giant armadillos and mammoths are. No beast nor full-fledged shaman would survive a 64lb shot at point blank range to the face. A counter-argument to this is that shamans are unusually agile. In our own world, armies had to deal with the fact that a single cannon shot might miss a target, especially a fast moving one. That is why barrages were and still are a thing. ### Going back to historical roots Shamans, just like the animals, are adept at melee combat. They will hardly be able to craft arrows that will withstand mammoth-force shots, so their best ranged tactics is using spears, and that places a harsh ammunition limit on them. At some point they have to run through enemy lines. The old-worlders may simply form a steel-lance and shield barrier and let the shaman come at them. Instant kebab. You may say that it is up to the battalion to hunt the shaman, and the shaman may turn the battle into a friction one if he just refuses to come close. No problem, just kidnap someone the shaman loves and torture them in the center of a tortoise formation. If the shaman still doesn't come, rinse and repeat. ### Dishonourable methods And if it all fails... Remember that the shamans are like the animals they hunt. The old-worlders are not constrained by honor as the shamans are. They can lay traps and use poison. The shaman is going to be like game and the battle is going to be like a hunt for the old-worlders. [Answer] **Organization.** The infantries fielded by European powers in these types of operations (conquest) are trained professionals - this as distinguished from an infantry drafted from civilians in wartime. Professional soldiers have practiced working together as a team. The individuals have roles to play within the group and they can count on their fellow soldiers to also do their jobs in an organized methodical manner. This is what allowed the Romans and later the British to acquire their empires. No doubt among their foes were phenomenally dangerous and accomplished warriors. No doubt some of these individuals were far superior to any individual fielded within the European infantry - I am thinking of the Zulu and before them the Gurkha, both of whom were defeated by the British. But an organized infantry operating as a single entity is more than the match of any individual fighter. from <https://en.wikipedia.org/wiki/Battle_of_Watling_Street> - detailing the defeat of Boudica and the indigenous British at the hands of a numerically much inferior Roman force. > > Tacitus also wrote of Suetonius addressing his legionaries: > > > "Ignore the racket made by these savages. There are more women than > men in their ranks. They are not soldiers—they're not even properly > equipped. We've beaten them before and when they see our weapons and > feel our spirit, they'll crack. Stick together. Throw the javelins, > then push forward: knock them down with your shields and finish them > off with your swords. Forget about plunder. Just win and you'll have > everything." > > > Boudica led her army forward across the plain and into the narrowing > field in a massive frontal attack. As they advanced, they were > channeled into a tightly packed mass. When the Romans had exhausted > their missiles, they rushed out in a wedge-like column. The Romans, > with a clear advantage in armour, weapons, and discipline, had a > decisive advantage in the close quarters fighting against the tightly > packed Britons. The Roman cavalry, lances extended, then entered the > battle. > > > As the Britons' losses increased, the Britons tried to retreat, but > their flight was blocked by the ring of wagons and the Britons were > massacred. The Romans killed not only the warriors but also the women, > children, and even pack animals. Tacitus relates a rumour that 80,000 > Britons fell for the loss of only 400 Romans. > > > The blood shamans would be formidable but individuals cannot triumph against a civilization with military tools like an infantry. What would probably happen is that the infantry would be impressed by these shamans (as the English were by the Gurkhas) and coopt them with the blandishments of civilization to join the military and use their might to the ends of the invaders. [Answer] The troops can overwhelm the shaman's senses, then chain it up. Is the shaman using his amazing sense of smell to track your troops? Splash a bucket of [bear urine](http://www.predatorpee.com/Merchant2/merchant.mv?Screen=CTGY&Category_Code=BEAR) in his face. Getting bear urine might be a challenge, but any powerful scent should do the job. Did the shaman hear your troops sneaking up on him from a mile away using his amazing sense of hearing? Luckily, each soldier is carrying a musket that can easily harm a human's terrible ear if they aren't careful. It should be devastating if one went off right next to the shaman's ear. Did the shaman's hawk-eyes see your troop's cleverly concealed pit trap? Light up a [flare](https://en.wikipedia.org/wiki/Flare#Chemistry) to disorientate it and harm its eyes. A combination of strong scents, loud noises, and bright lights should be enough to distract and disorientate the shaman for at least a few moments. While the shaman is recoiling and recovering from this assault of the senses, the soldiers can slap a collar around him and drive a stake deep into the ground to keep him in place for a bit. If staked chains can [keep bears in one spot](https://en.wikipedia.org/wiki/Bear-baiting), your shaman should be stuck long enough for either further imprisonment, or repeated [pike-ing](http://moziru.com/images/weapon-clipart-pike-3.jpg) by the troops until the shaman finally succumbs to his wounds. [Answer] > > A blood shaman kills a wild animal, and through a secret ritual gains > the ability to mimic its power. > > > 'Aint no animals that are immune to bullets. I'd imagine they would try and catch him in a musket volley. Even if he can survive a gunshot, or even a few gunshots, he'll go down if you put enough lead into him. They could get him with a cleverly placed barrel of gunpowder, too. Alternatively, does the old world have its own magic? They could send some witch hunters after him. The hard part would be compelling the shaman to stand his ground. If things are starting to look bad, it seems like he would have an easy time disengaging. [Answer] Unless there's a massive disproportion of numbers between blood shamans and colonists, or some blood shamans fight alongside the colonists, I don't see how they can be defeated. Killed, surely. If a blood shaman is stupid enough to charge against a column of musketeers, or put his head inside the mouth of a cannon, he can be killed, but why would (s)he do such a thing? Many answers have centered its attention on the animal skills of the blood shaman, when what it makes him a frigthening menace are his human skills: a powerful brain and a human body. The colonists are not the only ones who can resort to non-honorable ways of waging war. Why charge against an army in an open field, on broad daylight, when you can sneak your way into their night quarters and killing them in their sleep? It doesn't matter if it's a military camp in the countryside, a fort or a barracks in the middle of a village, our blood shaman can sneak through using his jaguar sigile, hide in the back of a chariot or just walk into the place in disguise. The guards are completely blind against his enhanced night vision and owl hearing. Even if he blunders and an alarm goes off he can safely fight his way away. Guns aren't a threat if they can't barely see you - but you can see them alright. It doesn't mind if this tactic has some limitations. A war is not usually won by annihilation of the enemy, but because the enemy has lost its will to fight anymore. The guerrilla tacticts of the iberian campaign of Napoleon destroyed the moral of the french army. Formed for battle in the open, they feared nobody (and won most of the battles until Wellington came), but they feared to walk away of the column for peeing. A scorched earth approach, as it has been suggested, it's not going to work. You can't hunt bisons with a 5,000 men army, you need hunting parties of 4 or 5 men, and who's going to be that insane? Venturing into the countryside, just five people, when a single blood shaman can kill a hundred soldiers per night in the middle of a fortified camp? No way. The fear blood shamans would inflict the colonists armies would be enough to prevent any colony to succeed. The civilian won't want to settle until the blood shamans are gone forever, and the soldiers are going to mutiny when the sun sets and fear starts (even if there aren't any blood shamans around). Unless more vulnerabilities are added to blood shamans, or some shamans change sides and side with the colonists I don't see the colonists succeeding. [Answer] Kill him with a blood knife and take all his power. Just kidding. The biggest thing would be to make sure to protect your flanks, protect your camps. At the same time, take and hold strategically important areas, such as ports, forts, rivers. Stuff like that that are essential to supply. As long as the Shawmans are only attacking in "the shadows" they will be hard to pin down an defeat. But as long as they don't inflict serious losses and you are still able to achieve decisive goals, I think moral will hold. Simply killing a handful of men, wile the commander is able to take ports and towns, will not beat an army. At the same time this may force the shaman to be more bold or attack in greater number. And if you can play the defender all the better. Essentially in the grand scheme of things a few killings in the middle of the night wont win a war as long as the commanders larger goals are still being achieved. For example if you get attacked in the dead of night and a few men are killed then the next day you go and sack a major town, which has the greater impact overall. ]
[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 6 years ago. [Improve this question](/posts/84502/edit) My country has a problem with concentration of wealth, rich people have few children and they tend to intermarry with other wealthy people. The wealth concentrates in less and less hands and soon we will become oligarchy. All those charity funds are just shams to pay less taxes. How to make them have more kids to spread the wealth? Democratic capitalist country. By law every child gets equal share. Adoption is fine too. Anything that would decrease concentration of wealth. Taxes won't help much due to openness of economy and rich people using tax shelters abroad. There's a whole industry of accountants and lawyers to make wealthy pay less taxes. On the other hand it's hard to hide assets from your own kids, at least for majority of parents. They are insiders who know things that tax auditors could only dream of. Wealthy don't have more kids due to cultural reasons. Wealthy get lots of education, then they start working their cushy jobs. Most of them start family late. And those who start earlier don't see need for more then one or two kids. [Answer] A simple change to tax codes could provide a huge incentive to the rich to have children: Change the child tax incentives from fixed amounts with percentage maximums to a straight percentage deduction with no maximum amount. For example, in 2017 in the US child tax credits and child dependent deductions max out at 6300 dollars (for 3 children) [[source](https://www.forbes.com/sites/kellyphillipserb/2016/10/25/irs-announces-2017-tax-rates-standard-deductions-exemption-amounts-and-more/#276669d65701)]. For the poor this amount could be significant, but for the wealthy ~6000 dollars is not a motivator at all. If however you were to reduce your tax rate by some fixed percentage this would be huge for the rich. For example if you went to a fixed 5% deduction per child: A family making 30,000 would receive 1500 dollars per child (similar to current amounts), but a family with income of 1 million dollars would see a return of 50,000 dollars per child. At high incomes you would hit a tipping point where the child would actually make you more income than it would cost. This would be a pretty straightforward tax strategy, I can see the accountants now, recommending having another child, or possibly pushing for surrogacy, adoption, or other non tradition options. This will save the rich lots of money immediately motivating them to have more children, and would as you desired, provide for more inheritors splitting the accumulated wealth upon their death. [Answer] There's a general theme here of aggressively closing loopholes, but in practice you want to open a new loophole. Remember that the drive of the wealthy is to increase and retain control of their wealth. If you push them too hard they'll leave for some overseas tax haven. Give them new loopholes to use to keep them interested in playing your games. Consider a loophole that for example, allows the family to bypass almost all inheritance taxes if the family wealth is held by a trust but only if there are at least 32\* trustees. Add a quirk that means the trustees can be no more distantly related than second cousins and it becomes advantageous for the family to be larger while occasionally buying out and spinning off "junior" branches as they become too distantly related to the "senior" line. Allow this mechanism to also protect the family wealth from divorce proceedings, something along the lines of each individual while apparently wealthy is merely being supported by the trust and has minimal personal assets, they're merely being allowed to live in trust properties while acting as a trustee. This can be emphasised by keeping entire branches of the family living in single large buildings. Should any behaviour bring disrepute to the trust they will be removed from the position and income cut off and evicted from the property. Getting divorced counts as behaviour liable to bring the trust into disrepute. \*arbitrary value significantly larger than the average family unit [Answer] Simplify the tax code, close the loopholes, and create tax on generational concentration of wealth. If family has 1 billion and they have only offspring they will have to pay 500 million in taxes. It will be up to them to decide would they have more kids, spend their money, or donate it. Tax heavens are actually easy to deal with, if and only if there is political will. [Answer] # What you asked Fundamentally, you're asking: > > How to [*motivate*] the rich to [raise] more children. > > > You also provide the following constraint: > > By law every child gets equal share. > > > which allows us to ignore the possibility of children being disowned and disinherited. But you also specified: > > All those charity funds are just shams to pay less taxes. > > > and > > here's a whole industry of accountants and lawyers to make wealthy pay less taxes. > > > So how do we motivate the wealthy to raise more children? By looking at what currently motivates them and structure raising children as providing a similar benefit. In this case, they are very clearly motivated by a desire to pay less taxes. Therefore, # Legislate tax breaks proportional to the number of kids raised. Write the legislation so that the amount of money saved from taxes per child is greater than the amount of money spent to care for each child per tax year. This creates a net-tax break. Structure the legislation so that raising more kids returns a greater tax break. More importantly: **do not cap it** leaving it uncapped maximizes the generational distribution of wealth. ## This creates a dangerous issue: exploitation How does one protect the children from malicious upperclassmen who intends to exploit them for financial gain? It would seem simple to legislate the following points: 1. Each child must be guaranteed a share of the inheritance. 2. Each child must be treated humanely (and this much be checked) 3. If the child dies or goes missing, formal investigations must be had. But, we're talking about the supremely wealthy and their armies of lawyers and accountants. Obviously, if they'd like to maximize their tax cut, they will be motivated to adopt a massive number of children. In the short term, this benefits them; however, in the long term, they may wish to keep their wealth and not distribute it after their death. Similarly, they may wish to keep the children at a *manageable* age to reduce costs and psychological overhead. Anecdotal example: rich teens invokes far more legal fees than rich 10 year olds. Or, they could sell the kids (ex: females) when they *reach a certain age* and make a tidy profit. Therefore, they may attempt to trade or remove kids from their parentage, be it adoption to another wealthy family, or 'mysterious disappearances' (read: murder, human-trafficking, slavery, prostitution). Without heavy government oversight, it would be simple for the obscenely wealthy and obscenely malicious to exploit lower-class adopters for financial gain. Similarly, one can see them forming the equivalent of a foster home. In essence, you'd be shifting the foster-care system to the wealthy; but, like the current foster care system, incredible oversight will be required to prevent exploitation. [Answer] Make men not to be afraid of losing property and money on marriage and divorce. Make divorce less beneficial for women. Having kids should not put at risk one's business. Here in Russia more than 80% of divorces are initiated by women because it is very beneficial and most men, especially rich ones, are afraid of marriage and having children because in that case they would have to pay child support without receiving anything in return (such as sex or comfort). The child support here is calculated as a percentage of income and has no cap, it may reach up to 70% of income if the man has many kids, it has 1% a day interest rate for late payments and those who fails to pay are restricted in rights (cannot drive, go abroad) and finally go to penal labor, their real estate being sold. As a result, the rich men usually strive to have no children while only homeless and released criminals want to marry (because they have nothing to lose). In your world the following measures should be implemented: * Rising the prestige and status of men in family, making divorce highly detrimental to women * Kids and common property should remain with the man if he wishes so. All man's investments in business are protected against divorce. * Divorced women are seen unfavorably by society, if with children they receive no child support neither from former husband, nor from the state, but encouraged to find a NEW husband as soon as possible. * The kids are supported by the current husband of a woman, the one with whom she lives. * Women are discouraged from working, studying and building carrier. The family is financed primarily by the man, so that women need a richer man for family. * The women are encouraged to marry at as young age as possible and have no choice of their husband (at least the first one). It is their father who would chose (in absense of father, the choice should belong to mother). This is because only adults can judge a man regarding his wealth and accomplishments, women, especially younger ones would in such cases prefer "love" which most likely would be criminals or hooligans (at least, so the case in Russia). [Answer] Just limit how much a person can inherit. Say each child gets no more than 500 times the national median income. Close loopholes. Nationalize all other assets: Give every citizen an equal share of such estates, in the form of coupons they can trade (or use to partially pay their own taxes). ***THEN*** The rich will have more children so they can distribute more of their wealth to their greater number of children and have less of it nationalized. Heck, if we don't demand their children be born in wedlock, and only consider genetic contribution; rich men might choose to have many dozens of children, "hiring" surrogate mothers with life-changing payments in order to provide them with more inheritors. [Answer] Well, raise taxes for the "wealthy bracket", but add generous tax deductions for having more than one child. The point is to make having children a strong way to save money. However, rich people won't start churning out people like bunnies just because of that. *Raising* children costs a lot of time and mental energy. Those are things that cannot be bought, and for the CEO kind of rich, it's in quite short supply. You'll have to help reduce that cost. That's a hot topic on itself, but stuff like having an ample supply of babysitters that can be hired/fired on the spot (richies love being able to do that), quality boarding schools so they can have little contact with their children and still feel good about filling their needs, etc. [Answer] Out of the top of my head, here's three: 1. Create a legislative upper bound on inheritance, e.g. 100m (the inheritance that is left to be held within proper institutions for children's children and so forth). [Not easy to play out right] 2. Make many-children families all the rage in fashion and a sign of wealth, for example by making it extremely expensive to bear and provide for it. [this would have adverse effects on the non-rich population] 3. **Legislate *inverse inheritance***: a child can only inherit from the wealth that the parents have when it is born/adopted. [devious] [Answer] People keep on talking about inheritance. I don't think that is the best lever. Mega rich people like Bill Gates have already disinherited their children to a large degree voluntarily. If we're going to really go for this then we can be **really draconian**. In order to ensure the wealthy have more kids push something like the following into law: > > You need to have 1 kid minimum per $500k in assets you control > > > If anyone can show you don't meet your minimum then they can seize your excess assets with the government retaining any assets that would exceed their limit. For the coup d'etat reward people who find loopholes in the law with proof that the loophole is being exploited the same grant of assets seized. This puts incentives in place to enforce the laws, as well as find loopholes, and forces people to have lots of kids if they want significant assets. Plus it makes "the new rich" from asset seizure adopt a bunch of kids just before seizure so they can hold onto the maximum amount of seized assets. Of course this is severe to the point of likely destroying economies, but it is a system where you get your desired result of rich people having lots of children plus checks and balances to make sure they adhere to the law. [Answer] Can you work on the cultural aspects of large families? In current American culture large families are seen as religious wackados or hippy kid collectors, for example. However, wealthy serial monogamist who build three families in their lives don't really raise many eyebrows. How to make large families cool? Cool nannies who are well paid. Make surrogacy cool and well paid. Bird nesting. This is where divorced parents move in and out rather than shuffling the kids from household to household. Rich people could do this in style and perhaps even add to their flock via surrogacy after divorce because their kids are just that awesome. This redistributes wealth in novel ways since some of this money will go to nannies and surrogates rather than just tax accountants. [Answer] What you are implicitly assuming here is the idea that wealth is concentrated and there is little social mobility. The true rule of thumb is that without the sorts of regulatory roadblocks and crony capitalist support system in place, families go from "shirtsleeves to shirtsleeves in three generations". So what is needed is to understand (and if necessary uncover) the ways which the wealthy try to "shut out" competition by ambitious and hard working middle class and poor people, and open up more channels for the hard working and ambitious to move up the social ladder. The reality, of course, is that this also means there are also more channels for downward social mobility as well, so rich people can suddenly find their families destitute, and poor people may remain poor due to poor impulse control and bad decision making. [![enter image description here](https://i.stack.imgur.com/vgod2.jpg)](https://i.stack.imgur.com/vgod2.jpg) *You can move quickly in either direction!* "Enforcing" equality through other means like confiscating people wealth and property is both wrong and counterproductive. There are plenty of examples of this, with Venezuela being the most current. [Answer] You won't need to force equal inheritance between children to accomplish what you want. Pass a law where money can be given to children through a trust fund. That amount can be deducted from their taxes at 120% (i.e. for every dollar they give their children, they get to keep a $1.20. That's huge.) The maximum transfer to each child is limited at 1/20th of the total taxable income. The trust fund no longer belongs to the parents, so the dispersion of wealth occurs instantly. [Answer] You can't make a wealth redistribution scheme that way. Money is usually need to make money, so billionaires having a lot of children would mean a lot of millionaires more. Some of them will fail and maybe lose their money, but if you have an idea, a lot of wealthy friends and acquitances and 50 million dollars to invest your chances of success are way better than if you have only the idea. With your premise you would go from a situation where 1% of the population has 30% of the country's wealth to one where 2% of the population controls 90% of the wealth, thus making unequality way more extreme. If you want to tackle concentration of wealth, just tax wealth (instead, or more like alongside income) and use the money to fund the great equalizers of the world: public education and social security. ]
[Question] [ Okay so I just got off an episode of Gotham where this > > electrician villain dude uses shock therapy to reprogram people to do his bidding. > > > Then I remembered that the brain operates on a sort of electric charge. Anyways, going by that logic, electric manipulator mage guy <=> energy in our brains, does this compute? Can he, somehow, guide these charges in a way that suggests he is controlling the person? [Answer] **I'm not a neurologist but...** It makes great *comic-book* science, but not *real* science. In real science, neurologists can control lab animals (from insects to mice) in carefully controlled experiments and in certain carefully constrained ways, via electricity. But these require: 1. opening up the skull 2. finding the right set of neurons in the right area of the brain 3. implanting tiny electrodes in those neurons so they produce shocks to *only those neurons.* 4. firing the electrodes within carefully constrained parameters to trigger responses or to change behavior/learning/etc. From the various shows/articles I've seen/read, this isn't mind control, but triggering responses or linking behavior to responses. It is to "mind control" what "I write code for the cable company!" is to writing viruses that infect alien space ships, spread throughout those shps, and include graphics that display on alien ship screens is in Independence Day. Oh sure, both involve a similar set of precursor ideas and baseline concepts, but they aren't the same thing. If you just fire electricity randomly at someone's brain, it will have some effects, but probably not anything controllable or predictable except in broad strokes. Wikipedia discusses the use of [electroconvulsive therapy](https://en.wikipedia.org/wiki/Electroconvulsive_therapy). That article notes that it can cause memory problems, including amnesia. Note the History section and how it has been used in the past. Again, this isn't just "firing an electric beam at target." Now, if you want to build this in a *comic book* or *far future* world, then sure. It is no greater stretch than Tony Stark making Iron Man armor in a cave or a high school kid making tiny arm-guns that shoot super-string webbing goo that he also invented to augment his spider-bite derived super powers. But I'd say this is a sci-fi technology *far* ahead of anything on earth now. [Answer] When your electromancer wants to control a human brain, he needs to be able to: * Perceive the brain of the target person with microscopic precision * Gain an understanding of how the brain of the target person works which is far, **far** beyond our current understanding of human neurology * Aim his electric charge generation with microscopic precision to make it stimulate exactly the neurons he needs to stimulate (potentially on thousands of neurons at the same time) But there are more crude methods than real mind control which he could use to get people to do his bidding: * Good old torture. He uses his abilities to cause pain to the victim until they will do anything to make it stop. * New, scientific torture, aka [conditioning](https://en.wikipedia.org/wiki/Classical_conditioning). The electromancer might discover that his ability can't just cause pain, but that he can also cause pleasure by directly stimulating certain brain areas. When he has a lot of time to spend with his victim, he could use pain and pleasure to mentally condition them to like or dislike being in certain situations or performing specific actions. This will be a traumatic experience for the victim and they will likely realize that they were conditioned. So there are limits to what degree of control he can achieve that way. He might not be able to completely turn someone, but he could use it to make his minions more loyal or to break a captive's will to oppose him even after being released. * He might just destroy certain areas of the brain of the target person to turn them into a mindless zombie. This would still require very precise control of his abilities and advanced knowledge of neurology, but is a bit more plausible than direct mind control. * You can cause people (or any other animal) to make involuntary movements by simply administering an electric shock directly to an individual muscle. The victim knows that the movement is involuntary, but can't prevent it. A skilled electromancer might use this to temporarily take control of someone's body. For example, when someone points a gun at him, he could make that person point the gun at their own head and make them pull the trigger. By the way, electrostimulation of muscles also works on fresh dead bodies, as long as rigor mortis hasn't set in yet. So he could force the hero to kill his best friend and then use the corpse of said friend to fight the hero. If that isn't grade A comic book villainy, I don't know what is. [Answer] Theoretically, yes. We can use this kind of technology on insects and some smaller animals. There's an article on Wikipedia about [remote control animals](https://en.wikipedia.org/wiki/Remote_control_animal) which is exactly this idea; controlling a brain through electric signals. Doing it to humans is a question of complexity, but it's certainly viable. [Answer] The answer is probably not, for a series of reasons: * You use the term "wills." Not everyone subscribes to the belief that our will is completely encoded in our brain state. Now the idea that our brain state holds everything is popular, and its the current prevailing scientific opinion, but it's worth noting that there's a whole slew of related philosophy questions that are currently unanswered. * Even if you assume that the brain state contains everything that is our consciousness, nobody has mapped one to the other. This individual would not only need to be a master of electricity to issue the finely tuned voltage differentials needed to do his manipulation, he would need to know more about how the human brain works that anyone ever before. * Every human brain is wired slightly differently, so he would have to learn each individual before bending their will. * Not all of our brainstate is electrical. There's also a vast amount of information transmitted by chemical means. Teasing those chemicals out into the open may be a tricky venture; we're still unlocking the secrets of how our neurons do these things. (Here's a [funny yet educational video](https://www.youtube.com/watch?v=tMKlPDBRJ1E) on the topic) There are plenty of things that such a master could do. Causing pain would probably not be all that difficult. But bending someone's will is a very different matter. [Answer] There are different ways to control people. Some of them will work, some are not. 1. Controlling the thoughts. Since our neurons are communicating through electrical impulses, it is at least conceivable that by providing such impulses from outside, one can control thoughts, memories and desires of a target. This, however, is outside of realm of modern science and would require a very detailed understanding of human thought process as well as high precision of control impulses. 2. Control by affecting the senses and emotional state. Electrical impulses can generate senses of hunger, pleasure, light, irritation etc. This is possible to some extent today in a lab. By providing precise impulses, manipulator would be able to control his target to some extent. 3. Control through Pavlovian reflexes. By giving someone a small shock every time he/she tries to do something undesirable, manipulator can have some control over target behavior. Doable, but with limited effect. 4. Muscle control. By providing impulses directly to the muscles, manipulator can cause his target to move unexpectedly. Doable, but manipulator should be able to see his target. [Answer] Given much, much more advanced levels of technology and understanding of the human brain, one could possibly conceive of doing something very basic like stimulating the amygdala to evoke fear, stimulating the pleasure centers of the brain, or suppressing the frontal lobe to repress decision making. However, another problem is that we often picture the brain as "sending electricity" from neuron to neuron to convey messages, but as often as not, things are put in motion by suppressing certain neurons just as you excite others. So most of the time, your efforts will probably be rewarded with a seizure. Now, if your electromancer can *detect* electricity, that would be something else entirely! He would effectively be a walking fMRI, and with enough work he might be able to, in a very crude way, read someone's mind. Or at least tell how hard they're thinking. In terms of bending people to your will, this could go a long way. It could also make him a pretty good lie detector test. If he could apply and measure current remotely, he could also monitor skin conductance like a polygraph test. [Answer] Unlikely. The brain operates by means of electrical signals, yes, but those are fed off chemical relays. Add in the microscopic size of each cell, the interconnection, which is different in each person and your master of electricity will have to work out the coding structure of a few billion nodes on the fly in order to produce an acceptable signal, that the rest of the brain won't simply ignore as a glitch. We do have [some] error correction. Also bear in mind that the brain itself is enclosed in its own Faraday cage of sorts, which will make getting signals in to affect its internal workings difficult. [Answer] Electricity from the circuit perspective : that current can electrocute and form a new fashion like a new path works against all logic without 1's and 0's bits going forth into all of 100 of 100% of logical more console interfaces like cgi and CGI as a domain not even for 90 days but for a day there would be CGI as 1bit and 1 bit as a digit of an image even 1 day or 1 bit not a whole control unless brought into a medium or fashion : this disproves displays and makes Electro shocking SpiderMan look like a verse rather than an attack even with high quality. This disputes into rather a quark or electron can travel into the brain which by polygraphs proves that people do see the effects of radio and particles but not stimulation not even now with cartoons and a twin tower attack. ]
[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 10 months ago. The community reviewed whether to reopen this question 10 months ago and left it closed: > > Original close reason(s) were not resolved > > > [Improve this question](/posts/243729/edit) I'm trying to come up with the label of an isolated location on a floating island where wizards go to practice magic in peace. I've already come up with the name, Skytower, but Skytower what? Is there a word for "sanctum" or "monastery" or "temple" but in an arcane/magical sense instead of a religious one? Here are some facts about it that might help narrow down what I'm looking for: * It's about the size of a castle or a town district, so the word should encompass the entire campus and not be a word for just a single room like "orrery" or for something small like "shrine." * It's not really its own political entity and it's not focused at all on military purposes, so stuff like "citadel" or "fortress" aren't what I'm looking for. * It's a place where experienced wizards go to study magic, practice it together, craft magic items, and most of all, just isolate themselves from non-wizards. It's not quite an "academy" or "university" for that reason, though those words are probably the closest I've been able to come up with so far. * Most of the wizards don't live there long-term. They go there for a couple weeks at a time to work on spells or create magic items, or they go there for conferences and symposiums, so words like "city" or "township" don't work. [Answer] ## Nemeton The modern idea of a sorcerer, wizard, or witch comes mainly from the Celtic tradition of druidism. [Druids](https://en.wikipedia.org/wiki/Druid) were religious and intellectual leaders who were reported to spend 20 years going off to thier holy places called [Nemeta](https://en.wikipedia.org/wiki/Nemeton) to study magic before returning as official druids (if they ever chose to return to normal society at all). These nemeta were typically caves, sacred groves, or simple alters but in some cases they were actual physical buildings resembling a temple or a church, especially in the Early Medieval period when you saw a lot of intermingling of Celtic and Christian religions. While a nemeton is still considered a place of "religious" significance, the Celtic religion put a lot more emphasis on the role of personal magic and arcane knowledge than they did on relying on the gods to give them things; so, if you were to for example, have a setting where Religion = Power from god(s) and Magic = Power from self based off of Earth's actual history, then nemeton probably makes the most sense. If your setting has Druids as a distinct class that are separate and very different than wizards, then this might not work... or it could lead to an extra interesting point in the history of your world where wizards and druids were once one in the same, but then branched into very different sects as civilization led many druids away from thier emphasis on nature. In this case Skytower Nemeton could be such an old "monastery of magic" that it still holds the title of nemeton from a time before magicians branched into different sects. ## Sohmehee Another tradition we can look to for the origins of "magic" as we now see it is the ancient Persians. The word Magic itself comes from the ancient Persian Magi who were a class of priests who were known to use illusions to fool congregations into believing they had supernatural powers. صومعه (pronounced "sohmehee") is literally the Persian word meaning monastery. While this word will be a lot harder for an English speaker to look up and understand its meaning and origins, the visual image of a Persian Magus with his library full of scrolls may be more in line with how you are picturing your monastery. [Answer] **Skytower Arcanum** Building a magical monastery are you? Remember monasteries are built in remote places. Isolated places. Places with few distractions from worshiping God. Or learning spells in this case. These monasteries are places far away from everything. Mysterious places known only to a few. Places full of secrets. Is there a word for something mysterious and full of secrets? Oh yeah! [![enter image description here](https://i.stack.imgur.com/Ozx8i.png)](https://i.stack.imgur.com/Ozx8i.png) Doubly good, for you since arcane has the genre-specific meaning of "to do with magic". [Answer] There is no single term for that throughout history. Keep in mind that the idea of magic as something fantastical that breaks the laws of physics comes from modern, fantastical literature. For many ancient magic practices, magic was how the universe worked, so we could also say it was their idea of what physics is. Therefore, you could take one page from hermetic magic and one page from Philip Pullman and use the word ***Magisterium***. When people think of alchemy nowadays, they think of a fantasy version of a subset of hermetic knowledge, which was encoded by a man named Hermes Trimegistus. The "megistus" there means great, and is related somewhat to the latin word *magister*, which means "master" (as someone who is knowledgeable). From it comes the word *magisterium*, which is the office of a tutor or instructor, and is related to other words that have to do with teaching. When the word made its way to English to become "magistery", it also came with other meanings. From [Merriam-Webster:](https://www.merriam-webster.com/dictionary/magistery) > > a principle of nature having transmuting or curative powers: > PHILOSOPHERS' STONE > > > > > > > he that hath water turned to ashes, hath the Magistery, and the true Philosophers' stone > > > > —James Howell > > > > > > > > > Then comes Philip Pullman, who wrote a fantasy novel series (His Dark Materials) where magic exists and atheists make sure that God doesn't exist by actually... No, not going to spoil that for you. Suffice to say that in this series there is an organization called the Magisterium, which oversees all things spiritual, scientifical and magical (though they try to oppress the latter, with little success). Or, you know, you could take a page from J.K. Rowling and call it a ***School of Magic***. Because that's what it is, regardless of what else people are doing while in there. [Answer] **The Skytower Institute of Magic** is one of the multiverse's leading multidisciplinary basic research institutions in spell casting and magic item crafting. This peaceful retreat is located on a Skypiea class flying island just 9 leagues north of the Cliffs of Insanity. It was founded 3 centuries before the common era by the generalist wizard Gælhalee, "Because flying islands are cool". [Answer] **Skytower Institute** > > An institute is an organisational body created for a certain purpose. They are often research organisations (research institutes) created to do research on specific topics, or can also be a professional body. > > [source](https://en.m.wikipedia.org/wiki/Institute) > > > "*The Skytower Institute was founded for the sole purpose of perpetuating the arcane knowledge, practices, and forgings of its proponents.*" An 'institute' is a secular (or non-religious) organisational body that focuses on research. It says nothing about its size or scale, nor does it imply a political or military interest. It requires no (pre-existing) structures, but can be based in and/or increase with a growing town. Lastly, it allows for people to come and go, for carrying out project-based tasks, for doing extensive, long-term research, for agents to have permanent or temporary positions. [Answer] When you go off to a distant location to study or work, isolated from distractions and other people, that place is often called a *retreat*. That word has no association with a particular use case, so the name *Skytower Retreat* would be equally valid as a religious monastery, an institute of magical study, or a fancy cabin in the mountains where government officials take foreign dignitaries to negotiate treaties. The similar term *hermitage* emphasizes that this is a place set apart from the rest of the world. It's most commonly applied to a residence, though, so it might only be appropriate if this place was built out of what was once a large manor. I'm a bit partial to the word *adytum*. Technically, it means "a sacred place that only a reserved few may enter". It originally referred to part of a Greek temple, but the description is generic and fits your magical academy perfectly. The word itself is fairly obscure and archaic, which makes it feel like a natural fit for something related to magic, and the definition has close parallels with other magic-related terms like *arcane*. [Answer] ## Use more than one word Perhaps the best known of the [examples in literature](https://en.wikipedia.org/wiki/Category:Fictional_magic_schools) is Hogwarts School of Witchcraft and Wizardry Or in the "real world" [Magic Institute of Excellence](https://courses.mieindia.in/) If you use a word that your readers don't know, it is of limited value. Though [Stephen R Donaldson](https://en.wikipedia.org/wiki/Stephen_R._Donaldson) might disagree as "His work is characterized by psychological complexity, conceptual abstractness, moral bleakness, and the use of ***an arcane vocabulary***, and has attracted critical praise for its "imagination, vivid characterizations, and fast pace" --- If you're a fan of Germanic languages, you can always jam multiple words together as a single world, e.g., Die Zauberflöte is the original German name for the Magic Flute opera. ZuaberSchule is a good translation for magic school. When I searched, ZuaberSchule is in actual use and even in the [PONS German-English Online dictionary](https://en.pons.com/translate/german-english) [Answer] I don't believe that any such word already exists. Everyone uses words like "school" or "university." The few that don't do that call it an "institute" or, even worse, a "bureau" or "corps". I suggest that you make something up. Pick a type of magic that best describes how magic works in your world, then make a portmanteau. For instance: Wizardrogy Sorceridge Arcanidemy The more your people use it, the more normal it will become. [Answer] An option borrowed from kabalah is [pardes](https://en.wikipedia.org/wiki/Pardes_(exegesis)) or PaRDeS as the acronym is sometimes written in english ``` Peshat (פְּשָׁט‎) – "surface" ("straight") or the literal (direct) meaning. Remez (רֶמֶז‎) – "hints" or the deep (allegoric: hidden or symbolic) meaning beyond just the literal sense. In the version of the New Zohar, Re'iah. Derash (דְּרַשׁ‎) – from Hebrew darash: "inquire" ("seek") – the comparative (midrashic) meaning, as given through similar occurrences. Sod (סוֹד‎) (pronounced with a long O as in 'lore') – "secret" ("mystery") or the esoteric/mystical meaning, as given through inspiration or revelation. ``` The word pardes in hebrew means grove or orchard, so the name pardes Skytower or skytower orchard could work pretty well, with the fruit referring to the knowledge cultivated. Additionally it lets you categorize your practitioners into tiers, from the relatively novice wizards of Peshat, to the deep-mystery experts of Sod [Answer] The most common word would be a university, college or academy. Note that the word *arcane* which you use literally means "hidden or secret knowledge", and was used for mundane scholars in early Europe, to describe things which they studied and practiced. The concept of naturalism is modern - it has an ancient history but came to prominence as "opposite of magic" during the enlightenment. So in a medieval setting there would not be much distinction between learning magical knowledge and learning mundane knowledge - without the scientific method and a reasonably mature theory of physics there's not a clear distinction between the two. People would care more about the fact that it's a place where people are *learning* some *uncommon* (i.e. *arcane*) knowledge, so the places of study of magic would be called universities, colleges, schools and academies. Following real historical tradition, I would expect a university to include several distinct areas of magic, or perhaps combine magical studies like conjuration and alchemy with mundane such as math, rhetoric and history. I would expect a college to house a group of peer or near-peer magicians who interact (whether through collaboration or competition) in their studies. A school or academy should have a clear distinction between a senior "teacher" class and a junior "student" class, with some students being destined for the former while others expect that upon graduation they would rejoin mainstream society with their skills and knowledge. A laboratory, sanctum or tower invokes the sense of an individual wizard, or small group, working on some project with little concern for educating the future generation of magicians. It could also serve as a workshop or place of business for a wizard who provides services to the general population, similar to an architect's office or a blacksmith's shop. Towers are preferred by political leaders, such as heads of magocracies, because it is a conveniently exotic counterpart to a mundane lord's keep or fortress, and is a bit like the Vatican palace. Witches like huts in wooded wilderness, often haunted. A conclave, cloister, lodge or guildhouse is what you should use if you want to emphasize that the wizards try to isolate themselves from society, perhaps they even operate in secrecy like a cult. This is different from universities and academies trying to create an environment free of layperson riff-raff so that scholars could learn in peace. A university's doors are always open and it's no secret what they do. Much like a library, the point is not to keep people out but to maintain a specific environment. So long as people conform to that environment they are welcome. With a conclave or cloister, I would expect that outsiders would be explicitly kept out and/or kept in the dark and seen as undeserving of the secret knowledge. For small groups, "hermitage" might also work. However, in your case it sounds like the location acts as a place of learning with general admission, so these terms would seem inappropriate. I wouldn't use something like "monastery". The point of monastery is for the monks within to quietly contemplate their faith, introspect, pray and minimize interactions with both the outside world and their fellows (many monasteries discourage chitchat and excessive socializing between brothers). This makes sense in a religious context, but for magical study it would be counterproductive, unless your setting's magic is very intuitive and based on ineffable inner strengths and wisdom which transcends words. Everything else is a fancy neologism, because it's used much less often in popular fiction, so people won't respond to it as a widespread technical term. If you don't want to use any of the above, you might as well just invent whatever word you think sounds cool, without worrying if it has much precedent for use. ]
[Question] [ I have this idea for a post-apocalyptic setting where my characters live in these RVs made during the pre-war era. That are basically mobile fallout shelters. Also, the setting takes place in my world's version of the USA. They look like Kharkovchankas. [![enter image description here](https://i.stack.imgur.com/AtIlZ.jpg)](https://i.stack.imgur.com/AtIlZ.jpg) They are designed to be an alternative to underground fallout shelters. Where people don't need to dig and build, but instead can buy an RV that can protect them from a nuclear bomb. The idea is the survivors can leave the area of the attack, without leaving their shelter and move to a safer location. It protects people from nuclear fallout but also, protects survivors from the elements and even other people in case society ever collapses. It's also designed to be comfortable and to have all the necessities needed for survival. So is it possible for a company or companies to design an RV that can withstand a nuclear bomb While keeping everyone safe inside and still functional? Edit: Okay so I'll explain in more detail. Originally the idea was for the RV to drive to a rural location, like a homestead, campground, or small town. It was originally designed just to handle nuclear fallout and nuclear bombs. Then I was wondering if it could withstand an actual nuclear bomb. So I'm just gonna only focused on whether it can survive a nuclear bomb. I doubt it would but if anyone has any other information. [Answer] ## Bunker or Fallout Shelter? A fallout shelter is supposed to protect mostly from nuclear fallout, not from a direct hit. And usually not for long. The occupants would stay inside for a few days, a few weeks, until either the *worst* of the fallout had abated, or somebody comes to decontaminate the way out. In that sense, something mobile could be a *great* idea. Assume that the bombs are either going to hit, or already have hit somewhere upwind. The would-be survivors enter their vehicle, check the weather reports, and drive out of the fallout plume. Their vehicle needs to maintain a sealed environment for a couple hundred miles, maybe. It might have to drive into destroyed areas if there is no way to detour around them. Shielding against radiation might require an impractical mass, but shielding against radioactive dust should be possible. Add an airlock and [decontamination](https://en.wikipedia.org/wiki/Radioactive_contamination#Decontamination) supplies. Of course this assumes there **is** an uncontaminated area to escape to. [Answer] > > is it possible for a company or companies to design an RV that can withstand a nuclear bomb, nuclear fallout, and nuclear winter? > > > A nuclear bomb maybe, nuclear fallout with some difficulties, a nuclear winter hardly. Why? Browsing around for how to build a nuclear shelter, I have found that most sources agree on having per person minimum 2.5 square meters, 140 liters of water plus food supplies and clothes. Add to the above a toilet and things start to become difficult. Let's go in order: 140 liters of water might be sufficient for the first days after the explosion, not for the whole winter. Unless you want to try your luck with using outside water, possibly contaminated, you have to find a way to reuse all the water you have. This means that your toilet can't be a hole toward the outside, but you actually will need to collect all your wastes and recycle all water they contain. This takes a not so simple system and energy. Same for air, you can't really trust outside air unless you filter it, which again takes a dedicated system and energy. And moving the thing around, which will not be flimsy like a car but will need some serious thickness to absorb all the bomb emission, takes also additional energy. All that energy will need to come from the fuel you carry along. I wouldn't rely on gas stations along the road, either because who is going to stock them or who would step out to do the refueling? Additionally, the more mass you want to stumble around, the more difficult and slow your movement becomes, especially in a post attack situation, as the Germans learned the hard way with their humongous wunderwaffen tanks during WWII. I assume you don't want to get stuck into a muddy ground and waste all your fuel into attempting to get out of there. [Answer] Lotta questions here... > > So is it possible for a company or companies to design an RV that can withstand a nuclear bomb? > > > No, although this is mostly a question of distance from ground zero. To block a nuclear blast, one simply needs thick mass, which is incompatible with a vehicle that's designed to go places. That said, blocking a nuclear blast is also quite simple, you just need mass. Simply encourage people to park their RVs in ditches or specially dug underground garage pits and they will likely be fine since the blast/shock-wave simply passes overhead. > > nuclear fallout > > > Sure. Nuclear fallout is not *difficult* to handle on an individual level, it is broadly speaking just irradiated dust. Any vehicle that's already designed with desert operation should be fine. Sealing the cabin to dust would be a bit more difficult, because you would need an integrated airlock/shower system instead of conventional doors, but again, totally doable. > > and nuclear winter? > > > This one is a bit tricky because staying warm is a combination of preventing heat loss and generating more heat. Insulating such a vehicle well is doable, but at the end of the day, you are simply going to need large amounts of stored energy to make up for the energy loss (big fuel tanks). > > While keeping everyone safe inside and still functional. What fuel does it need? > > > You need an energy dense fuel that holds long. This is because, realistically, the apocalypse RV is going to spend a lot of time sitting around being ready, but not going anywhere. Diesel holds a bit longer than Gasoline, however even with stabilizers, they are only going to hold 3 years top. Kerosene is probably be a better pick, because it is stable for up to 5 years standard and that's before adding fuel stabilizers and since it's basically heating oil, it should be salvageable from homes in an emergency. > > How will survivors get clean water and air? > > > A reverse osmosis filter will clean water handily and they are quite simple and portable (although the do eventually require filter replacements) and can even treat wastewater. Water can be scavenged from basically anywhere and run through it into an onboard 'clean water' tank. Air filtration is even easier, since fallout-laden air is heavy, an air intake that simply faces downwards will already do a great job. Just slap a standard AC HEPA filter on it, and ensure that the RV is a positive-pressure environment, and you will be fine even if it isn't airtight. > > How will they get food, if their rations run out? > > > They can simply buy/scavenge prepackaged food. Unless they are literally at ground zero where food has gotten irradiated directly, canned or otherwise airtight-packaged food that was made before the nuclear event will be fine. Fresh produce or other unpackaged food should be avoided though, since it may be contaminated with fallout. **Summary:** Unless you are killed due to the immediate effects of a nuclear blast (shock/fire wave, collapsing building, radiation flash, etc) or die soon after the blast due to absorbing too much radiation, managing fallout isn't that difficult for an intelligent and prepared individual. The average home could easily be converted to be fallout proof with just a caulking gun, a HEPA filter, and an HVAC set to positive pressure. Similarly, your simple basic N95 mask would quite effective at dealing with fallout if you need to go outside (although a good shower afterwards is still recommended) Hell, there are plenty of modern vehicles that are already "fallout proof", notably the Tesla Model S with the "bioweapon defense package" air filter system. All it takes is a decent filter, positive pressure, and you're golden. ]
[Question] [ Suppose someone went back in time to kill Hitler and fails and some modern tech falls into nazi hands. What modern technology could they realistically reverse engineer with 1940's tech? I'm leaving the time travel tech itself out of this and am most interested in what modern tech they would be able to make sense of. For the sake of argument, the time travel device is only one way and remains in the future. Our failed assassin might be carrying standard items that an assassin in 2021 might carry on them (phone, gun, nvg). Also, let's assume that there are no easy shortcuts and they haven't done anything like downloading the entirety of Wikipedia or arxiv onto their phone for the trip. [Answer] # No. Nothing to add to @AlexP answer, except that, for a comparison, the Manhattan Project's main difficulties were in *getting pure enough materials and precise enough tolerances*. In other words, even knowing exactly what something is and how it works (and here we have neither, not "exactly" enough), you still have the problem of engineering it. In other words, you could have sent the prints for an A-bomb, the theory, the bill of materials, detailed instructions on how to produce and assemble each part, back in time to the USA (or Germany) in 1939 - and they probably wouldn't have been able to shave more than a couple of months from Project Manhattan's time table. To be helpful, what you need is *information* on how to cleverly use something they already were able to use. But the fact is, people are and were quite clever - they were *already* doing next to the best they could with what they had. So, no way a failed assassination and its loot might help Nazi Germany. # ...and it gets worse. On the other hand, even a failed assassination might spell utter disaster for Nazi Germany, because of its implications. *(Had they been *sane*, the reasoning below might have helped Germany and the Nazi indirectly, by telling them to **quit** while they were ahead. To sue for peace, and consolidate their earnings, and be able to strike again, perhaps more decisively, at a later date instead of hurtling towards a destroyed Germany. But I think this not to have been the case)*. > > "So, Herr Doktor. Do you have any results yet for our Fuehrer?" > > > Werner Heisenberg shrugged. "The technical report is under way. I have no great hopes, as you can imagine. But..." > he paused, considering his next words. There were things that no sane man was going to tell to a Party commissioner, ever. And yet... > > > "You have seen the man's devices. His weapon. That strange gadget he had in a pocket. You know, of course, the conclusions we've arrived at." > > > "You mean the time-traveler theory. Yes, of course. I understand this is established truth. Which is exactly the reason why we want to know everything possible about the man's devices and technology. His communicator alone could win us the war." said the Commissioner impatiently. "So?" > > > "Do you realize the effort - the technological effort that must have been necessary for this man to come back here? The energy required? Do you not realize what this has to mean?" > > > "Explain yourself, Doktor." > > > "Someone, years in the future - our estimates range from a minimum of one hundred years to a millennium - some *large*, very powerful entity, like a government, possibly a *planetary* government, sent back an assassin to kill our Fuehrer. *Why* would they have done this? Think! *What kind of government*, what kind of people would want this done?" > > > "I... don't think I quite see." > > > The physicist raised his voice. "Don't you see? Time travel must be exceedingly difficult, or we would be up to our ears in time travelers. The man was soft, well fed. He was no warrior. He came from a peaceful world... his can not have been a desperate attempt but rather a deliberate, well-researched endeavour. There is only one explanation for this mission to have been allowed -- to have been *conceived*. Why *this* mission specifically, and not another." > > > He took a deep breath. > > > "I could tell you nothing, but the facts are all out, for everyone to see. The story is too big, and it's already too late to silence. The conclusion is logical and inescapable. Somewhere, in the next few years... the Third Reich must have lost. So horribly, so *finally*, that future generations will not be content with letting things stand, but endeavour to wipe us all out from the very history." > > > [Answer] * Gun. I am quite sure that whatever gun the wannabe assassin carried it was pretty much the same as what guns they had in the 1940s. There is nothing to reverse engineer. Except maybe the materials, if the gun has some parts made of modern polymers. It wouldn't do them much good, though. They already knew what a polymer is, and they already had some pretty nifty polymers, such as, for example, [plexiglas](https://en.wikipedia.org/wiki/Poly(methyl_methacrylate)) (aka acrylic glass). * Phone. The essential parts of modern smartphone cannot be reverese engineered with 1940s technology; they would even be hard pressed to realize it was a radio communication device -- they had very limited capabilities of detecting electromagnetic waves in the relevant frequency ranges. The microprocessor and memory would be complete mysteries; chances are they would destroy them while trying to see how they worked. The *battery* of the smart phone, they could understand what it did spend a lot of money and effort trying (fruitlessly) to understand how it worked. The screen... That depends on the screen. For a cheap backlit screen they would understand the lighting. For an OLED screen, nothing. It's way beyond what they knew. * Nvg. I have no idea what an nvg is. If you mean a night vision goggle, they already had such devices. [Answer] Focusing on the phone, If there was a demonstration of the capability, perhaps recorded on film, that showed the phone playing music, videos, or animated games, or even the calculator it would immediately stimulate tremendous interest. For example, just showing computations of sines, cosines, logarithms etc. out to 12 or 15 decimal places would reveal a lot of potential. But even assuming the battery had depleted a tremendous amount could be learned using the technology of the time, especially in material science. Even if the phone had been smashed, one could imagine a dedicated laboratory being set up to study the technologies. With an optical microscope with a 50 or 100x objective (reasonable at the time), they would be able to understand pixels, see the interconnections and probably deduce photolithography was used. They would marvel at the cameras, and immediately understand what they were and conclude that some type of “artificial retina” had been constructed. With the printed circuit board they would recognize the solder, but not the lamination technology, but would understand it is a lamination technology and understand that circuits could be made, they would understand resistors, capacitors etc and be able to measure them. Integrated circuits would be beyond them initially, but they would identify the silicon as an extremely pure materials and would point them in a good direction to pursue. Again, they probably would recognize that a lithographic process had been used to define features for the printed circuit board. They would probably recognize the LED as some type of lighting device since it has a lens, and since it has two wires may be able to recognize it as a diode, perhaps light it up and eventually identify the materials that was made of. Even things like the insulation on the wires and types of wires would be of interest. The battery would be of tremendous interest and since it is clearly labeled battery with specifications, they would know exactly what it is. Although, they would probably be puzzled as to why it was made in China. There would be other written clues inside the phone. Just knowing that a lithium-ion battery could be made would give a large head start. To keep this reasonable length, in the 1940’s there were a lot of very bright people, a lot of good basic science, physics and chemistry, and a phone would reveal a tremendous amount of material science, optics, assembly techniques, and ideas of what is possible. The ideas behind the field effect transistor predate WWII, and the junction transistor was right around the corner in 1947, so in the right hands a phone would reveal a lot. Initially, just understanding the quality of the materials and what the materials were would really jump start a lot of interesting technologies. [Answer] **Some ideas** A modern, high-capacity semi-automatic would certainly be a step forward compared to then-current designs. The positioning of the magazine release, double-stack magazines, a trigger guard obviously designed for a two-handed grip, ... *Exhibit A: The [Luger P08](https://en.wikipedia.org/wiki/Luger_pistol#Pistole_Modell_1908_(P08)_and_World_War_I) with eight rounds in the magazine. Exhibit B: The Colt [M1911](https://en.wikipedia.org/wiki/M1911_pistol), great stopping power but just seven rounds and quite a kick. Exhibit C: The [Browning High Power](https://en.wikipedia.org/wiki/Browning_Hi-Power). Exhibit D: The [Mk23](https://en.wikipedia.org/wiki/Heckler_%26_Koch_Mark_23) with many of the optional extras. Imagine someone from the [Reichssicherheitsdienst](https://en.wikipedia.org/wiki/Reichssicherheitsdienst) going "Build something like that for us."* If the assassin has night-vision gear, how about a modern tactical vest? The arrangement of the pouches might strike them as sensible and replace the old-fashioned LBE. Lots of little detail improvements they could copy. **No practical effect** Nothing that would make a difference on a large scale (e.g. introducing transistors on sort-of-microchips) will be reverse-engineered and fielded in time before the Soviet tank armies overrun the Eastern front. [Answer] Here is a frame challenge. The question asks about modern technology, as if modern technology would be 2021 level technology. Inventing time travel requires technology decades, centuries, millenia, tens of millennia, etc. beyond the technology of 2021 - or considering how late in 2021 it is, let us say the crude technology of 2022. Humans in the year 2022 with 2022 technology will never be able to invent time travel. Not in any plausible story. So assassins sent in the past to assassinate someone will use weapons far more advanced than anything we can make in 2022, possibly more than we can imagine. Possibly the assassin will simply arrive in the past halfway around the world from Hitler, think a command such as "Die! Hitler, Die!" and his technology will kill Hitler in a way that German doctors will be unable to understand, and which the assassin will not bother to think about since it is so simple and basic when he comes from. The only possible way for a time traveling assassin to use incredibly backwards and primitive 2022 technology to assassinate someone in the past would be if the time traveler was from 2022 and aliens from outer space with technoology thousands or millions of years more advanced arrived on Earth and gave time machines to humans. Or maybe time travelers from the distant future arrived and gave time machines to humans. And if humans asked the aliens or time travelers from the future if they could use the time machines to assassinate evil persons in the past, and the visitors said "Sure. Why not? What's the worst thing that could possibly happen if you try that?", and the 2022 humans couldn't think of anything particularly bad that could happen, then I guess an assassin could be sent into the past with primitive, backwards, crude, 2022 level technology. [Answer] Guns could provide a new design, although honestly it's not much (if any) improvement. Anything electronic very unlikely. While it is possible (with enormous care) to reverse engineer electronics by stripping the cover material and taking photos of each layer, here they've got one shot and just about any mistake dooms the entire enterprise. Plus, even if you do somehow reverse engineer the chips you don't have anything to run on it. They've got absolutely no way to save the software off the thing, let alone any needed firmware etc. ]
[Question] [ Okay, so I had this idea that there is a group of refugees (a majority of them civilian families) taking cover from an invading force, vanishing into a mountainous region that serves as a natural fortress to protect them. These refugees are fairly ethnically diverse in the beginning, and number between 2,000-2,500. Assume level of technology to be bronze age, or thereabouts. Surviving in the mountains will be tough, and I assume that they will lose people to injury, illness, and exposure, especially in the beginning when their surroundings are unfamiliar to them. It also isn't realistic that they would be completely isolated, so assume that there are marriages with outsiders occasionally, even if that is culturally frowned upon and ends up being rare- perhaps one every few generations? Keeping all of that in mind, how long would it take said population to develop fully into their own ethnicity, both in appearance and in genetics? [Answer] ## Ethnicity is an Idea first, Biology a distant second: There is a similar question [HERE](https://www.quora.com/How-long-does-it-take-for-a-culture-to-become-its-own-ethnicity) The problem with race and ethnicity is that the divisions are largely cosmetic. That is to say, all you need is for your group to LOOK different from the surrounding people, and they are considered different. If you have a distinctive feature, like red hair or a funny nose, then as soon as that trait is prevalent in the society, it's an ethnicity. The line between culture and ethnicity is a fuzzy one, and I'd argue that in practical ways, it's an illusion. There isn't an absolute scientific rule saying what an ethnic group IS or ISN'T. And ethnicity is a murkier thing even than race, which is in-and-of-itself a controversial topic. Uyghurs, for example, are considered racially Central Asian (if you want to make the distinction), but based on language and religious differences, they are considered their own ethnic group. The Chinese government certainly considers them different, and the efforts to eliminate their culture are labeled genocide. But it can take even less time if you have something in the environment that imposes conditions on people to change their appearance. Say one group has abundant meat, and their children grow taller than their neighbors. With cultural differences and language drift, they could be an ethnicity in one generation. Do you consider (European) Australians to be an ethnic group or a nationality? If so, then it took maybe 150 years (or less). So your group isolates, then their weaver develops a particular clothing style based on local materials. They have lots of garlic, and so all their food has garlic because there are almost no seasonings to be had (spices were huge in the ancient world). Ted the blacksmith likes to say "belike" in a funny way, and everyone likes Ted, so pretty soon the folks sound a little like Ted and it becomes more pronounced when Ted becomes mayor. His wife was from France and French words creep into the vernacular. Ted likes to bathe every day, and learning how to make lye soap becomes a priority as habits establish themselves. The one preacher in town has his own ideas about God, and his teaching is a bit off from the surrounding communities, but everyone goes with it. So now people settling new areas but coming from your village dress differently, talk differently, eat differently, worship differently and possibly SMELL differently (garlic can be strong, and soap important). They may have fewer skin problems because of good hygiene, and Ted was a good mayor, so the kids are tall. King Ted the second keeps the community together even as it spreads. Now they track government differently. So I'd argue that within a single generation, you have AT LEAST a unique culture, and will likely be considered a unique ethnicity. As Ted's big nose spreads through the population, the Tediites will be an ethnic group within perhaps three generations. Large numbers of other peoples in close contact will blur these lines, but that's because ethnicity is in the eye of the beholder. [Answer] I upvoted @DWKraus' answer, you should too, but I want to add more insight. **Answer: 30 Seconds** > > eth·nic·i·ty (/eTHˈnisədē/) noun: ethnicity; plural noun: ethnicities • **The fact or state of belonging to a social group that has a common national or cultural tradition.** (Source: Oxford Languages) > > > Your group of refugees met that definition the moment they became refugees, sharing a common enemy, a common plight, and the common goal of survival. If, on the other hand, what you meant was, "if a community of some 2,500 people begin with a variety of ethnic backgrounds but became isolated, how long would those backgrounds merge into a reasonably homogeneous single ethnicity?" **Answer: Basically never** One of my go-to examples of the complexities of ethnicity is the historical background to the [Bosnian Genocide](https://en.wikipedia.org/wiki/Bosnian_genocide). From 1918-1992, Serbia, Croatia, Bosnia, Montenegro, Slovenia, and Macedonia were better known as Yugoslavia (My thanks to @AlexP for correcting me!). For nearly seventy-five years four generations of people lived in first the kingdom and then the socialist state. They worked together, played together, intermarried between ethnicities, fought together... And then came ethnic independence. And then came war. And then came genocide. What the world learned from that experience (among many other things) is that hate can be quietly and effectively handed down generation-to-generation no matter how closely people are brought together. From a very real perspective, you need more than 75 years to merge peoples into a single ethnicity. We can look at nations all over the world showing better-than-average conformance and worse-than-average conformance. Let's take France for example. The Greeks, Gauls, Romans, Germans, English... they all fought and mingled until today where you have a remarkably tight culturally bonded people. I've known some French people — they're amazing! And when you get their nationalistic and, perhaps more importantly, cultural backs against the proverbial wall, there's being French... and there's everybody else. Compare that to the U.S. where we have ethnic divergence all over the place, often at odds one with another. Skin color. Dialect. Heritage. A 250 year melting pot that has not in any way created a single ethnicity and probably never will. Whether or not your people will create a unique ethnic heritage depends on some very powerful factors. * What heritage did they come from? Was that heritage traditionally submissive or arrogant? Was it traditionally inclusive and tolerant or xenophobic? Was it a big deal to be a member of that ethnicity, or was it just something you were and being a member of a political party was more important? Etc. * What animosities exist between the initial ethnic representations? Remember, hate can and will last a ***honking long time.*** Remember Newton's *First Law?* Hate is one of those powerful forces, and it will remain in motion until acted upon by an equal or greater force. Yeah... think about that. When the Beatles sang "All You Need is Love," they were very right... and very, very wrong. If you don't believe me, wait until one of your children turns 13 (All you need is love! La-ta-da-da-daaa!) As a friend once said, "I finally understand why lions eat their young...." * What conflicting social/cultural rites exist among your group? Does one have a religious practice that another finds heinous? Let's throw polygamy into the mix and let one of the polygamists' sons start dating your daughter. * Are there physiological differences between the ethnic groups? Skin color? Eye shape? Nose size? Height?.... As you can see, your group will take as long or as little time as you desire to develop an ethnicity. You can create all the initial starting conditions to justify the time you want it to take. Thirty seconds or a thousand years. It's really up to you. There is no single right answer. > > *'Cause at the end of the day, long as there's two people left on the planet, someone is gonna want someone dead.* (TF2, The Sniper) > > > [Answer] In truth modern science cannot not really answer this. Actually, it probably could, but… because of issues that are grounded in politics, racial debates, and the fears of indigenous people in the Americas (North & South), science has not been able to make its best attempt at solving the wide spread, and very hotly debated question that you ask. Remains from a group of people known as the Clovis people have been found all over the American continents, as far as I know, more commonly in the Northern continent, than the south, however; the Southern continent, and Mexico (which is technically part of the North, but perhaps a more accurate description, one that is often used to reference the Mexican Region, would be Central America) has produced much much older anthropological finds, including artifacts and human remains from periods that predate the latest known period that the Clovis people lived in the Americas. If you read this article, you can get a good idea of the arguments raised in this subject. The whole point to mentioning the topics that I did above, is to raise the question where did Native Americans come from, who were their ancestors? There is a wealth of data on this topic now that could help us answer these questions, but the “should be easy to collect data, has not been so easy to collect”. To tell what remains belonged to persons that were related, ancestrally, to the Native American Tribes people we must test the DNA of the remains, then test the DNA of modern Native Americans. Any attempt at doing this pisses someone off. Many tribes will not give consent to not only sample their DNA, but they have had legislation passed that prevents DNA testing of their ungraved ancestors, or of any peoples predating contemporary European settlement. In-fact many of the remains we have found, have had to be study rather quickly as legislation has forced scientist to rebury one of a kind precious remains. With that said, there has been some work done, with some useful data, but the conclusions produced from the data are arbitrary, and more data is needed to reinforce the claims made by Archeologists, and Anthropologists. [Link that demonstrates arguments about this subject](https://web.archive.org/web/20151016014746/http://www.reuters.com/article/2014/02/12/us-science-native-americans-origins-idUSBREA1B1TS20140212) There is pretty good evidence that the Clovis people are very distant relatives of many of the Native American Tribes people, but what is hotly contested is the remains found that predate the Clovis people, DNA shows some similarities, but as stated previously, all DNA work that could be done, has not been done, and several chances to do DNA testing have slid right by us, and are no longer available due to the re-graving of remains that were never DNA tested when they were ungraved. Currently it is theorized by some scientist, and this is becoming more widely accepted with the passing of each day, and not a lot of new data coming forth, several American Tribes are descendants of the Clovis people, this is easy to accept because DNA evidence suggests it. The group of people that predate the Clovis people show DNA similarities with the Clovis people, but they don’t show much evidence as being related to the North American Tribes, however, the key word is Much, there is little evidence, but not nearly enough to conclude concretely. Furthermore, upon the topic of scientific theory, it is hypothesized that the data shows exactly what you would expect to see when a new ethnic group is established. The latest ancestors don’t show a lot of DNA resemblance, but more recent ancestors show damning evidence that they are related to the new ethnic group, therefore; it is very likely that the reason we see less and less Native American resemblance as remains grown in age is simply because the remains grow less related with age, this is in fact how it works. It's not as simple as I made it sound when I concluded the last paragraph, but I believe that what I have said, and so do many others, that what I have stated above is at-least partially true. It would be hard to say that it would take a specific number of years to form a new ethnic group, but when coming to a conclusion based solely on the data that is available, it looks like 24,000 years or more. [Answer] I don't think there is a 100% clear cutoff line, because ethnicity is much more of a social distinction than a physical one. Is Anglo-saxon a different ethnicity from white european? Is Scottish an ethnicity separate from anglo-saxon? Is lowland scottish separate from highland scottish? Are American Scots a separate ethnicity from Scots living in Scotland? Are American scots a separate ethnicity from Canadian scots? Is Scots-Irish its own ethnic group separate from Scottish and Irish? What about American Scots-Irish vs Canadian Scots-Irish? What about Canadian Scots in Nova Scotia vs Canadian Scots in Ontario? Which of those count as separate "ethnicities", and why? What if an Ulster Scot immmigrant to Indonesia who identifies as Scots-Irish has a kid with someone who is Han Chinese but speaks Bahasa Indonesia and identifies as Chinese-Indonesian -- are they ethnically distinct from someone who differs from that only in that their second parent is Hui-Chinese instead of Han-Chinese? If you have a village with two predominant family lineages, one of which has greater percentage of blue eyes, and the other which has greater percentage of green eyes, are they considered ethnically different in appearance from each other? What if their larger culture thinks they are ethnically different? What if their larger culture thinks they are ethnically the same, but they themselves think they are ethnically different? There are a million other grey areas. Willk is probably right that 6 generations is a decent estimate assuming a genetic mutation occurs in the first generation that directly translates to a clearly distinguishable change in appearance, with perfect conditions and everybody marrying each other completely randomly (would this really be the case?). However, I would argue that the minimum for being treated as a separate ethnicity would be **0 generations**. Simply living somewhere else could be grounds for some cultures to believe they are ethnically different. Even differences in food, nutrition, fashion, living conditions, etc. could be enough to cement a commonly-agreed-upon ethnic division. Human history is full of stories of people drawing arbitrary lines between each other and declaring their own tribe's uniqueness over the others. [Answer] They would not regard themselves as an ethnic group. They would regard themselves as basically, a group, and those outside are the outsiders. For instance, in 19th century France, villagers would refer to a bride who came from outside -- meaning another village. This group comes with a natural regard for themselves as a group, since they can easily distinguish themselves from the invaders or the cowards who submitted to their rule. The necessity to work together would reinforce this. In time, their language and culture would diverge, and their intermarriage will homogenize their genetics. (Especially culture, since they now face the necessity of doing things differently in the mountains.) However, they would not regard this as a difference between themselves and their ancestors. They are still those who fled to the mountains to avoid submission to the invaders. "Ethnic group" is something this would be termed by outsiders. [Answer] There are plenty of good answers already, so I will just provide some additional information on the subject. It is not possible to give you a reliable estimate because the speed of cultural homogenization depends on several different factors. Some of the most important are: 1. *Diversity of the original group* (do you have dominant ethnic or cultural subgroups? what are their relationships with other subgroups?) 2. *Patterns of marriage and settlement* (do people from different subgroups intermarry? do subgroups live in their own 'ethnic' villages?) 3. *Religions* (are there big differences in religious views and traditions? how strictly religions are observed? can people of different denominations intermarry?) 4. *Governing and policies promoted by the leadership* (do leaders promote intermixing and intermarriage? do leaders allow 'ethnic' villages? do leaders strive to achieve cultural homogeneity?) 5. *Environment* (can the group split into subgroups without endangering itself? what kind of activities are required to sustain the group? how much cooperation is required for survival?) With an initial population of 2000, it is possible to end up with 2-3 ethnic groups if the original group had 2-3 big factions that differed in culture, language, and religion, cooperation was not very important, people quickly settled down in small 'ethnic' villages and did not intermarry. On the other hand, if people had to live close to each other, had to work together, intermarried quickly, and did not have major religious disagreements cultural homogenization would happen rather quickly - within 2-3 generations. [Answer] Let us assume "ethnic group" means they can be distinguished as that group on sight. Let us start with something harmless and spectacular like the methemoglobinema of the Blue Fugates. [![blue fugates](https://i.stack.imgur.com/QPFGT.jpg)](https://i.stack.imgur.com/QPFGT.jpg) <https://dnascience.plos.org/2016/09/22/finding-the-famous-painting-of-the-blue-people-of-kentucky/> Let us assume that the gene conferring the appearance is autosomal dominant like Huntingtons, so instead of needing a double recessive like the Blue Fugates you have a 50% chance of manifesting the phenotype if you have an affected parent. Let us assume further that there is a fitness benefit to this appearance such that for whatever reason more children with the gene will live to have their own children. We will assume a stable population of 1000. In this population, every child with the gene grows up and is part of the next generation. Other children might or might not. There is 1 founder among the refugees. In the second generation the founder has 5 children. Each of these children have 5 children, so 25 with the gene in 3d generation, 125 in the 4th, 625 in the 5th and by the 6th generation the entirety of the 1000 person population carries the gene which confers this group their appearance. --- Of course there is more to "ethnic group" than skin color. I am sure though after 6 generations this isolated group would certainly have their own customs and would likely speak in a dialect hard for outsiders to understand. [Answer] > > how long would it take said population to develop fully into their own ethnicity, both in appearance and in genetics? > > > Somewhere around a few thousand years to ten thousand years. 1. If you simply pick any Old World population 10k years ago and keep it isolated, you're almost guaranteed to end up with distinctive one by nowadays standard. Why? Because nowadays we're quite mixed, for example for Europeans are mixture of three such population. Any of those ancestral groups (Western Hunter-Gatherer, Anatolian Farmers, Yamnaya) would right now look somewhat distinct, especially WHG. 2. Upper bound - out of Africa split has happened 70k years ago. So that would be the time that's guaranteed to work. 3. If you need it to be really fast - then you have founder effect with very small starting population with odd gene variants and genetic drift. (ex. they had a few red haired people at start and by purely random event they become the dominant allele in a few generations) Also pay attention to local climate - if it's totally different than original one, then it would force quite fast evolution. (think: Inuit) [Answer] ### Three to ten generations, maximum There's a lot of good answers here, but let's start by breaking down the genetics. The only hard line in genetics is speciation. That's when two sets of genetics are far enough apart that they can't produce offspring. For human-ish genetics, that's roughly half a million years worth of evolution. If you just wanted to homogenize skin color, you're looking at around 2,500 years, or 100 generations. That's how long it takes to shift from fair to dark skin, or vice versa, but ethnicity doesn't require that. It would take only ten generations before everybody shared some common ancestors. Natural selection and breeding instinct would have gotten rid of the most divergent of genes by then. The people would likely have started grouping by obvious traits, forming sub-ethnicities, in half that. All of that might seem meaningless when you consider that most of what we think of as ethnicity is cultural instead of genetic. It isn't. Memes are passed around between humans the same way genes are, with family groups hanging on to them most tightly. Shared experiences are what creates a culture. By three generations, the people will have more shared experiences than they have historical precedence before isolation. After five generations, pre-isolation culture will just be fairy stories. The most blatant change, though, would be in clothing styles. Even in bronze age, I give it ten years before everyone is dressed in highly distinctive rags. ]
[Question] [ If aliens were to bring a space ship to the solar system, and put it in orbit around a Jupiter moon, and then begin colonising the surface of the planet, what would we be able to see from using current day technology? Presuming the best case scenario, i.e. we are at a close orbit with Jupiter, etc. How big would their ship need to be to be visible to us? Are there any 'major' telescopes regularly pointed at Jupiter, or would it be more likely picked up by someone with a (big) telescope in their backyard? How long would it take us to develop / deploy a probe to investigate (and how long to get there)? ETA... The main question here is about visibility. With today's technology, what would we see? [Answer] **Probes!** Yeh, Fish suggested this in the comments. But here is a sweet image! [![europa](https://i.stack.imgur.com/lqdCx.jpg)](https://i.stack.imgur.com/lqdCx.jpg) > > This close-up view of the icy surface of Europa, a moon of Jupiter, > was obtained on Dec. 20, 1996, by the Solid State Imaging system on > board the Galileo spacecraft during its fourth orbit around Jupiter. > The view is about 7 miles by 10 miles (11 kilometers by 16 kilometers) > and has a resolution of 28 yards (26 meters). The Sun illuminates the > scene from the east (right). > > > <https://europa.nasa.gov/resources/110/close-up-of-europas-surface/> Check out the crater that cleared off the cracks next to it. The link explains what happened there - stuff melted and flooded! 26 meters is good enough resolution to make out an average sized middle school and you could easily see a golf course. In any case - there has been a pretty steady presence of one probe or another out Jupiter way. [A dedicated Europa mission](https://europa.nasa.gov/mission/about/) is going to happen sometime this decade. [Juno](https://www.nasa.gov/mission_pages/juno/main/index.html) is out there now and it has taken some incidental pictures of Europa. A Michael Crichton type fiction would have the Earth folks make use of resources like Juno already on the scene to get a better look at what was going on with Europa. [Answer] **Without offering any proof for my assertions...** 1. Electromagnetic emissions that don't belong. Should your aliens use EM transmissions (optical or radiometric), then it's possible to detect them here on Earth using current tech. After all, we're still detecting both Voyagers, and they're a honking lot further away than Europa. 2. Heat. This one is a little less believable because it would depend on the resolution of thermal detectors... but unless your aliens are using some cool tech (every possible pun intended), the exhaust from their ship(s) could be detectable. 3. Shadows. A number of previous answers have suggested that our cameras simply aren't good enough to detect a ship of reasonable size. However, that doesn't mean that the ship orbiting Europa (and, therefore, Jupiter) at an opportune angle to the Sun wouldn't cast a long shadow that could be detected and shouldn't be there. You'd have to be watching at just the right moment for something like this, but it's possible. (Consider this in real time. A shadow suddenly appears on the surface of one of the two spheres, momentarily grows longer, then vanishes... talk about cool ju ju for your story.) 4. Radiation. Rather than assuming a combustion-style engine as I did in #2, let's assume a nuclear-style engine. Those things burp radiation all over the place. 5. And with a [massive caveat](https://worldbuilding.stackexchange.com/q/193036/40609), depending on what the surface of the ship is like, and if the angles are once again opportune, the flash of light off the ship could be detected. (I admit that this is a specialized version of #1, but #1 was meant to convey communications tech, not happenstantial "oh, crap, we didn't think about painting the darn ship!" problems.) 6. Finally, and this one is way out into left field, consider the possibility of an exotic drive like the Albecurrie drive. We're warping space, donchaknow... and I wonder if warping space means you're warping gravity right along with it. It might be that if the navigator brought the ship out of warp just a little too late, the result would be a small but detectable shift in the orbit of Europa. Gravity, it's a harsh mistress.... [Answer] This is what Hubble can see from Europa, as published by [NASA](https://www.nasa.gov/press-release/nasa-s-hubble-spots-possible-water-plumes-erupting-on-jupiters-moon-europa) [![enter image description here](https://i.stack.imgur.com/Q6qOi.jpg)](https://i.stack.imgur.com/Q6qOi.jpg) > > This composite image shows suspected plumes of water vapor erupting at the 7 o’clock position off the limb of Jupiter’s moon Europa. The plumes, photographed by NASA’s Hubble’s Space Telescope Imaging Spectrograph, were seen in silhouette as the moon passed in front of Jupiter. Hubble’s ultraviolet sensitivity allowed for the features -- rising over 100 miles (160 kilometers) above Europa’s icy surface -- to be discerned. The water is believed to come from a subsurface ocean on Europa. The Hubble data were taken on January 26, 2014. The image of Europa, superimposed on the Hubble data, is assembled from data from the Galileo and Voyager missions. > > > The plume at the bottom of the planet is about 8 pixels in height. Taking for good that its height is 160 km, it means that a single pixel resolves about 20 km. This means that anything smaller than 20 km won't be resolvable: we would just see it as a single pixel. Forget about reaching those resolutions with a backyard telescope. [Answer] Regarding, "*... would it be more likely picked up by someone with a (big) telescope in their back yard?*", the Hubble Space Telescope is among the highest resolution telescopes in existence. According to <https://hubblesite.org/contents/media/images/2009/12/2508-Image.html>, "*Hubble can see details as small as 190 miles (300 km) across on Saturn.*" from Earth using its Wide Field Planetary Camera 2 ([EDIT] a different instrument than the one used in the other answer), so your hypothetical spacecraft would need to be at least that large and distinguishable from the background to be detected even by Hubble. A backyard telescope has no hope of detecting such a spacecraft, short of it being extraordinarily luminous. If you want to do estimates, this site discusses the details of Hubble's resolution and limitations: <https://illuminateduniverse.org/2019/04/11/angular-resolution-and-what-hubble-cant-see/> [Answer] If your aliens are technological civilization, they will probably use radio-frequency communications. Or their machinery will emit radio frequency electromagnetic waves we could detect. I think we will manage to intercept their communications, first - accidentaly ("what is this strange interferences?"), than intentionally ("we have tuned radio-telescopes and send probe to Europa to investigate strange radio interferences coming from it"). Than probe will find something unusual on orbit and surface of Europe... [Answer] The answer to your question is it depends if the aliens want to be seen. If they want to be seen they could send out radio messages, generate unusual heat or magnetic effects and paint the ship bright orange among other possibilities. If they don't want to be seen then there would be little chance of finding them as things stand. They could use some fairly simple camouflage to blend into the background making them virtually invisible. They could also maintain radio silence and modify the heat signature to look like something else like a diffuse plume from a crack in the crust. If they simply don't care then its hard to say as they might or might not give themselves away by various means. All other things being equal I think we would be very lucky indeed to spot them unless the colonization process was already very advanced and covered a substantial area. [Answer] ### Rocket engines are bright. Simply put, any rocket engine capable of taking off and landing on the surface of Europa will be quite bright, whether it's a chemical rocket or some form of nuclear rocket. It's got a surface gravity of about .134 Gs, so you'd need a rocket with a thrust-to-mass ratio of at least that much in order to land there. However, given that this is interplanetary or interstellar flight, you're going to need to burn your rocket to decelerate, and that drive plume will be extremely visible. The luminosity of the rocket would depend on how large the rocket is, how fast it's going, and its acceleration, but it's entirely possible that a torch ship pulling a 1g acceleration would become visible to the naked eye, and amateur astronomers might notice it as a new "star" - a new "star" that is moving, no less! Something like an Alcubierre drive might not create such luminous plumes, but if you're flying FTL, you won't be able to see where you're going, so it's entirely possible that it won't show up immediately in Jupiter orbit, and it'll need to perform rocket burns for interplanetary flight to get there. It's also entirely possible that we might see such a rocket approaching by observing the distortions in the light of other stars that it would produce, though that might require a bit of luck in pointing a telescope at an area where it happened to by flying past. ]
[Question] [ We human lives in a four dimensional universe: three spatial dimensions and one dimension for time. We feel the flow of time as experiential due to the fact that our brain saves past experiences into memories, but in fact the past does not exist in any physical meaning. In relativity you can say that someone's future had already happened in another's past... anyway let's get to the main point. Imagine a creature who exists parallelly across every instances of time, so its entire life is predetermined. I wonder: what would it need of memory? [Answer] **To know what is happening at the other end of its body,** This creature passes through time the same way a fence passes through a field. The fence has a start and an end and everything in between, but in reality the fence is there all at once. Similarly the creature already exists at all points in time at once. Imagine you are lying down in a field, with your right hand being in the *past* and your left hand being in the *future*. There are some *special ants* that live according to field time. They are born at the right side of the field and due to some unexplained force move leftwards throughout their lives. They interpret field time as real time. One day an ant bites your right hand and by instinct you close your left hand. This crushes the ants walking on your left hand. From the ants' point of view you are a high-dimensional creature that has remembered the bite in the past and used it to act in the future. From your point of view however it all happens at once. It's not a memory but just your sensory system. The creature works the same way. What you might call memories it just calls its nervous system. Of course none of this answers the question of how a full-dimensional creature would experience its lifetime if its consciousness does not pass through a timelike dimension. In the field example there is the higher dimensional real time and your consciousness passes through it linearly. You can act in the ant's past but not in your own past. How does a five-dimensional creature work if there is no sixth dimension for its consciousness to move along? It throws up loads of other questions. You also need rules for avoiding time paradoxes.\* \*Assuming you're into that sort of thing. It's your world after all. Feel free to have as many paradoxes as you want. I promise I won't tell mum. [Answer] The concept of memory is a tad different for a creature who lives across every instance of time. While for us memory is "remember what happened in $\mathit{Life}(t-x)$ while we live in $\mathit{Life}(t)$, for your creatures memory is simply "be aware of every value of $\mathit{Life}(x)$ in its entire dominion. So, let's say John Doe was born in 1965 July 11th and died in September 2010 November 4th. The time spread John Doe's "memory" would simply contemplate each and every moment of its existence in that time span, like we see a segment made out of all and every points belonging to it. By the way I don't think that > > a creature who exists parallelly across every instances of time > > > qualifies as 5 dimensional creature. [Answer] To understand things. If it turns its attention to John Doe's fourth birthday party, and has no memory, it has no memory of why it turned its attention on that date and time, and no understanding of its significance. If you merely mean that it is conscious of its life and thoughts in a manner different from ordinary humans but does indeed know of what it was doing at them, it's not really not having memory. [Answer] Lets assume this 5th dimension being named Jack is a human, or at least has the basic human biology externally. We humans can move freely in 3 space dimensions and forced to move unidirectional in time. A 5th dimensional being by that logic should be able to move freely in 4 dimensions and forced to move unidirectional in a 5th dimension, or simply be capable of perceiving a 5th dimension. With this established, there are two reasons to have memories: 1. what exactly is this 4th and 5th dimension. Time when seen as 2 dimensional, leads to a past-future dimension and a parallel multiverse dimension. So if 4th dimension(free movement) is past-future, then Jack is able to perceive his entire timeline simultaneously, but as he moves to another timeline, he can no longer perceive the other timelines, hence the need for memory. If past-future is the 5 the dimension(forced) for Jack, then that means Jack can perceive all possible "presents" simultaneously and move in between them, and needs memory to store these presents.An example of this would be tossing a coin and then being able to move between the two timelines of one with heads or one with tails. 2. If jack has human anatomy or anything of the kind seen in nature, he can only perceive a limited portion of space-time. Jack cannot know what is behind him or far away from him. So when Jack moves, his perception changes. But how would Jack know if his perception changed ? there in comes the need for memory. [Answer] Did you watch the 2019 version of Watchmen on HBO? It played quite well with this idea. Dr. Manhattan's consciousness exists simultaneously at all times his body ever inhabits, and the story plays pretty well with the paradoxes of backwards causation this can appear to cause to regular people who experience sequential time. He is able to transmit information from other character's futures into their pasts. As for what "memory" means to him, memory is just a mental store of information. It happens to be that, because we experience sequential time, all of the information we store, from our perspective, was gathered in the past. Some creature that does not experience sequential time still has need of knowledge, even if, from its perspective, it acquires all of it at once. Wherever that knowledge is kept is "memory." ]
[Question] [ The warp is a realm that is separated from reality by a barrier, keeping denizens from interacting with each other Daemonic possession allows for a daemon from the warp to take possession of a human body as a host. It involves a ritual in which a human is sacrificed to the daemon, with ancient symbols carved into the flesh to bind the daemon to that particular host. These binds enslave a daemon to a master and force it to obey commands, allowing the mage to retain limited control over its actions. The problem is that even though a daemon is bound to a host, it is still susceptible to the same daemon weaknesses, such as holy weapons, holy symbols, etc, etc, which allow it to be sent back to the warp. In addition, the daemonic essence eventually corrupts the body of the host, ultimately destroying it. Over time, the form becomes more daemonic, adopting features attributed to the daemons true form and making it obvious that the body is possessed. The daemon is forced to expend more energy to retain the body and prevent it from breaking down completely, cutting down on its effectiveness. To get around this, an ancient cult devised a millennia-long eugenics program. Over thousands of years, they would practice selective breeding among their members, recruiting outsiders when necessary or obtaining genetic samples through other means. The end goal would be to produce a perfect host for a daemon with the correct genetic makeup to contain it with no issues. This host would have all the benefits of daemon hosts with none of the weaknesses, and be able to maintain the daemon long-term with no issues. After this child is conceived, a ritual would be performed in which a daemon would take possession of the embryo and be born in the human body into the world. This project ultimately proved successful. However, with advances in technology, the cult believes it can speed up the process for future possessions. The creation of the artificial womb has allowed children to be grown in batches, drastically cutting down on time and effort. Genes can be taken from a variety of parents and be mixed and matched to create a person with the correct genetic makeup. The cult has the financial means and influence to create facilities where embryos can be created all at once, with those successes being brought to term and failures being exterminated. This would allow them to create an army of daemon hosts quickly and cheaply. I need a reason for why a millennia-long eugenics program would be a more preferable option of creating a erfect daemonhost, despite advances in reproductive technology. Why would natural birth be lead to the most successful outcome? [Answer] **Lab grown don't have a soul** A deamon can only puppeteer the body if they can latch on to the soul. Lab grown babies and red heads are too far removed from biology, forgoing their right to a soul. No soul, no bond, per definition no perfect host, regardless of all other traits. [Answer] **Demons are old school.** There are only a couple hundred of them, total. A few are really old but most of the ones still available came of age right around the same time the eugenics program kicked off - the formation of new demons and the start of that program having the same underlying reasons. The younger demons reminisce about the glory days, speak fondly of the eugenicists who kicked off that program, the silly stuff they did, the hell they raised. How awesome it was back then. They think the vat grown thing is weak. Like old rock and rollers listening to a loop on a synthesizer at a live performance. "Like listening to my dishwasher!" The demons like the old ways. The really old demons have different preferences yet. Some of them fondly remember all the tricks they had to use to get more mileage out of a random human body that was falling apart - like graybeard old coders thinking about the tricks for code when working memory was measured in kilobytes. This new stuff just doesn't grab them and shake them. What is needed is a new batch of demons, right? [Answer] **Not a Matter of Genetics.** It is really hard to genetically engineer a super-genius because intelligence is not determined by a single gene. Rather it's some combination of all the genes and also how you were brought up. The same holds for demonic possession. No one has isolated the important gene(s) and many suspect it is impossible. You can of course breed two good hosts and sometimes you will get an even better host. But unraveling how that happens from the genetic code is really hard. [Answer] The most simple answer is a head start. It would take a long time to raise a human for long enough, then kill them, sacrifice them, and evaluate the result properly. If you had a few millenia you could have refined it much further even if the new method is faster. For example, experiments on foxes suggest they can be domesticated, but this is nothing like what we have achieved with dogs that we've been domesticating for over 10,000 years. Given a long lead time, a mild or even significant improvement in efficiency won't be enough. [Answer] **Timing** is everything. You'd only be caught without your umbrella and get wet if you're not anticipating sporadic rain. If you live in an area where it rains every day, you'd walk around with an umbrella, and keep dry. The demons can **detect the trick when it's done in batches**, in a matter of every couple of years. They're foul evil villainous demons, not idiots. [Answer] The effects are so delicate that the artificial wombs and the chemicals necessary to genetically engineer things throw things off. Or possibly they can not rule out the effect and would rather stick to what is already proven. [Answer] To add a completely different option, the whole issue could also be caused by **politics**. ## Inertia Your cult already invested thousands of years to eugenics, constantly having to live with breathing the ashes of their former friends. Now some scientist comes along and says that this suffering has been totally unnecessary, and that there is a much easier way? If the whole eugenics thing is a sufficiently deeply ingrained tradition (which it would have to be for many generations to put up with all the unpleasantness) the mere suggestion of a possible better way would lead to lynching, not to mention actually trying to implement something like growth labs. ## Power Politics Or perhaps the cult aristocracy happened into a political position defending eugenics against early - clearly absurd - 'improvements' to the process like Frankenstein-humans, and made it a policy to execute everyone arguing against the current paradigm (perhaps their political enemies were always the greatest supporters of new technology, and admitting to advantages of such technology would undermine their ruling position?). ## Demon Feed on Suffering The politics could even extend into the demon realm - what if the whole eugenics program isn't even meant *primarily* to produce better hosts (that being a nice side effect), but rather to feed the demons with all the suffering inflicted in the secret concentration camps? Only a few humans - if any - would know about this, and changing the process to a cleaner one involving growth vats and killing off non-sentient embryos based on their DNA just wouldn't work for the purpose of the demons (this works best if eugenics seems more morally acceptable than "pointless" torturing of innocents, but the advantage of *slightly* better hosts might still make eugenics the preferred options for the demons even if it isn't any easier on the humans). Additional twist: maybe even the demons don't know how the suffering is what truly stabilizes the bond, and they might be just as surprised to see the genetically perfect vat-grown bodies fail as the human cult members are. ## Technologically Advanced Suffering If you want the breeding program to be actually viable at a later point, you could say that the genetic improvements *do* help, but that to create the perfect host you'd have to *technologically optimize suffering* surrounding the creation of it so the bond will hold. This idea might also work well as an even darker part 2, depending on what you are intending to do - ie. imagine the heroes discovering that while they defeated the eugenics cult, a splinter group has been perfecting technological breeding and suffering in secret without having to worry about the assassins from their former cult, and can now try to take over the world with perfect demon-fused soldiers. [Answer] **The effects of the rituals are cumulative, and additive** Each ritual has its own evil, foul taint. Each ritual is unique in its terrific hideousness. However - the intentions and flavor of the evilnessness of the ritual linger in the cosmic ether, waiting for another, similar experience. **As each ritual is performed, it draws a tiny extra bit of Darkainium (a common name for evil-dark-horrible-villainous-energy-that-is-bad) from the remains of all past similar rituals.** Over the millennia, these bits of Darkainium amount to quite a bit. Current estimates are at 1.9TD (Tera Darkainium) !!! Aside from the accumulation of Darkainium, **each ritual's flavor adds a unique spicy ting to the whole wine cask of badness.** Each host created nowadays is both full to the brim with Darkainium, and tastes of many well aged previous successful participants. Now you wanna start a new process, break down the monolith and go for microservices? Bah! You can't go wrong with the old ways! Maybe combine this with @Puppy 's answer for a full old man's hardware development project. [Answer] ### Development within a human womb is necessary to prepare the child One of the traits selected for by the eugenics program is compatibility with the human host. A 100% compatible demon/host would not degrade the host body, and the demon would be so fully integrated with the host that traditional weapons would not be any more effective than they would against a normal human. However, this trait it not fully genetic, part of it is inherited from the mother during development. Exposure to the various energies and chemicals that would make one compatible with a demon comes through the mother. Part of the eugenics program is creating the perfect mother, in order to give birth to the perfect host. A lab-grown baby would not be exposed to these same energies/chemicals/hormones, and artificial replacements that work equivalently have not been found. ]
[Question] [ I'm thinking about giving my humanoid aliens two stomachs. If a person were to have to two bigger stomachs, would they have to eat more? If their stomachs would bigger, would they have to consume (eat a large portion of food) lots of food and would it take longer to digest? Edit (More detailed) I wanted to give my humanoid aliens two stomachs because I was interested in the idea. I was inspired by Stafire from Teen Titans, who has 9 stomachs. I do have a clear picture of what my aliens would look like with two stomachs but how would it work? I'm sort of ignorant when it comes to stomachs because I don't know much about the way work. When I meant when someone were to have a bigger stomach, would they require to take in more food and would digesting be slower? Or if they had two stomachs, would the digestive process be the same or faster? [Answer] Yes and no. You have your cause and effect backwards. They don't need to eat more because they have multiple stomachs and a long GI tract, they have multiple stomachs and a long GI tract *because* they need to eat a lot of food that takes a long time to digest. Compare herbivores (especially ruminants) to omnivores to strict carnivores (e.g. felids). As you go from animals that eat a large amount of difficult-to-digest matter (cellulose, in particular) to easy-to-digest matter (meat), they have fewer stomachs and shorter GI tracts, and food moves through their bodies more quickly. If your aliens ate meat, it would probably go through quickly. If they have two stomachs and a long GI tract, they probably eat a lot of plant matter that takes longer to break down into useful nutrition. [Answer] **Not exactly** Stomachs are a mechanism for digestion. The amount of food a human consumes on a daily basis has very little to do with the size of the stomach, and has more to do with the amount of energy said humans expends. Or, more correctly, the causation arrows are flipped - the size of the stomach is based on how much food a human needs to eat, not the amount a human needs to eat being dependent on the size of the stomach. The concept of 'overeating' or eating more food than your body needs is a trait used to store surplus energy. Why would a creature have multiple stomachs? Well, as you guesses, a larger digestive system. Complex and mostly indigestible foods (i.e. grass) require a long digestive system to handle. Koalas, for instance, having an incredibly long and complex digestive system and it's basically just for eucalyptus leaves. Having two stomachs help digestion, and that's why your aliens have them. As for the biology - well, you have choices. Multiple stomachs can be connected to another, as in Stomach A leads to Stomach B, or a mouth will lead to both of them and the creature will force food from one stomach back into the mouth before sending it to the second stomach. Or, in the case of ruminants, both! [Answer] Having had my complete large intestine surgically removed a couple of years ago, I have a bit of relevant first hand experience here :) At least in humans, the function of the stomach is to break down food chemically, but the function of he GI tract is to process it further (using the diverse population of micro-organisms which live there because it is a less hostile environment than the stomach) and also to recycle fluids back into the body by absorbing them instead of excreting them. Removing part of the GI tract decreases the "transit time" of food through the system, which means that some vegetables (e.g. peas and sweet corn) are not "digested" at all and emerge looking pretty much the same as when you ate them. There is also a significantly higher loss of both fluids and electrolytes - for example I now typically need at least 3 liters of fluid per day to stay properly hydrated, and high-salt foods are not "unhealthy junk" but a necessary part of my diet! So having multiple stomachs on its own doesn't necessarily have much benefit, unless, like ruminants, you can recycle material between GI tract and one or more stomachs, to repeat the two processes of breaking it down chemically, and absorbing the nutrients from it. [Answer] It might digest faster, at least the part that regards the stomach, as there are 2 stomachs doing the job and thus there's a better chance of a larger contact surface, though I can't say with absolute certainty. Regarding how much food, a stomach is an organ that requires a decent amount of maintenance, so keeping 2 of them will likely require more resources and thus more food. Though to be truly honest, it sounds better to just have one larger stomach, as I don't think the second stomach would speed up this part of the digestive process to make up for their maintenance and energy cost. Additionally, the stomach is but a single part of digestion, with the main nutrient absorption happening at the intestines, so I don't see enough advantages in more than one stomach to make its presence worth the extra energy, nutrients and space required. Cows for example, rather than growing another stomach, simply divided their single stomach in 4 main divisions to fit their diet, so here's an example of how a single stomach can already do what's needed for it. [Answer] Two stomachs would be a great advantage. It isn't uncommon for a lot of animals on earth. Read about **microbiotic digestion**. A lot of bacterias can digest things, a human cannot digest. Rabbits eat their own excrement to gain advantage of the extra proteins produced by the bacterias, because they do not have a second stomach. With a second stomach, you could digest the bacteria like a cow. But digestion could be slow because bacterias need to grow in the first stomach. So, an humanoid with two stomachs could **survive with a really meager vegetation** for food and would **need less food** than an ordinary human. But there could be some problems with gas, it might be inconvenient for us to live with such an humanoid in the same house. [Answer] There is a big difference between whether the stomachs of your alien are aligned in parallel or in series: **In Series:** Food which is entering the body, enters the different stomachs one by one. This has been answered already: a number of plant-eating animals have multiple stomachs, which are used to digest food which is difficult to digest. **In Parallel:** * Two different stomachs might be used to digest different kinds of food. I don't think this is something that occurs on earth (correct me when wrong). But I can imagine that the fluids in the stomachs can be of a different nature. So the alien's body could choose which stomach to use to digest the food he takes in, allowing him to diverge the types of food he can digest. * Two stomachs of the same type (so without different 'fluids') could be treated the same as a bigger stomach. A bigger stomach for the same amount of food intake has the advantage that the alien doesn't have to eat that often. Our eating pattern is (amongst other factors) defined by our stomach size: if our stomach is full, we have to stop eating. If our stomach would be 10 times as big, we could survive by eating only once per week (hypothetically of course: there are more factors playing here besides the stomach size). Snakes for example are known for their big stomach-to-body ratio. ]
[Question] [ My world is parallel to ours, except alien doppelgangers have infiltrated human society for generations to hide from their enemies in space. They have positioned themselves to stop their rivals from establishing relations with the humans at all costs. A doppelganger of the President orders a nuclear strike on Washington DC from NORAD after new aliens (their rivals) arrive to make first contact in 1969. The real President is in Washington DC and desires to prevent Washington DC from being nuked. Given the command and control structure of the strategic forces at the time, could the real president of the united states prevent a nuclear strike on Washington DC, or would orders issued from NORAD override any efforts from Washington? * Both presidents are in control of their respective bases (DC vs. NORAD) and assumed by local commanders to be the real president. * The supply of doppelgangers is limited, and they are unlikely to sacrifice themselves, so the fighting will be between humans. * The doppelganger president has approximately the same knowledge and access to command codes as the real president. [Answer] # The CIA would know that an imposter president is possible The aliens just pulled the same stunt in Russia. Unless the CIA decided to sleep while the most important event in world history happened in Russia, they should have noticed what happened and briefed the US leadership about it. So we can assume that the US leadership knows that the V2 aliens are capable of impersonating political leaders and might use this ability to destabilize countries. # The Secret Service would know that at least one President has to be an imposter The Secret Service is the personal bodyguard of the president. Knowing the whereabouts of the US president at all times is their job. The POTUS doesn't go anywhere without the secret service planning every inch of the route and securing it. So it is simply not possible for the US president to just show up somewhere without the secret service being informed. If the V2 aliens are really smart and use more than just one infiltrator, they might perhaps be able to use some subterfuge to *confuse* the secret service about who is the real president. But they could not convince one half of the secret service to guard one president and the other half to guard the other one. Not without these two factions being aware of the fact that they are suddenly guarding two presidents and without the Director of the secret service realizing that. # With the possibility that one president is an imposter, the military would not execute the order One President has a reasonable diplomatic approach to the alien situation. The other wants to kill a million US citizens to prevent a first contact, which is a completely unreasonable approach to the situation. And the V2 aliens tried to pull the same stunt in Russia. Military officers are not stupid. Considering these circumstances they will question if the order to launch a nuke at Washington DC is a legitimate order and very likely refuse to execute it. # Conclusion In order for this V2 alien plot to work, a lot of humans would have to act pretty stupidly. # What's likely to happen? * The Secret Service would detain the "President" in NORAD as a potential alien spy. * There is a possibility that people in Washington DC would stop listening to the President in DC. If the one in NORAD is an imposter, then it's not an unreasonable hypothesis that this one is also an imposter and that the real President is probably on a dissecting table on a V2 alien space ship. They would then likely let someone else speak for the US during the first contact. Probably the Secretary of State (because this is a foreign affairs matter) or the Vice President (as the next in line when the president is incapacitated). * If the V1 aliens aren't stupid either (and considering that they figured out interstellar travel they have to be pretty smart), they would also know what is going on and not rule out the possibility that whatever hairless monkey claims to speak for Earth is actually a V2 alien in disguise. [Answer] **No.** The President will be watched closely at all times - especially a conventional establishment President like Nixon. There is a reason the real Nixon is in that bunker. He was moved there for his safety. His whereabouts are known at all times and not just incidentally, but by people who are employed to do just that. If Nixon strolls into the White House (presumably with a doppelgänger secret service detail) the secret service / security still in the White House will ask how he got there and why he left the safety of NORAD. While these questions are asked, calls will be made to NORAD and it will be established that Nixon is right where he was the day before and the day before that, with the individuals comprising his security detail. At the very least, the new Nixon whose origin cannot be accounted for would be held prisoner while issues were sorted out. To substitute new for old, you must do away with the old first or at the same time. You would think pod people would know this! [Answer] Willk did a good job of addressing the problem of a doppelganger president. I'd like to address the topic of the President's (or any politician's) role in the military in the event of an invasion of the United States, particularly as applies to nuclear strike options. While the use of a nuclear strike option in theory rests solely with the President, the actual ability rests with the operators. And this was particularly true for the era in question (1969). At that time there were few locks in place to technically prevent the operators themselves from activating and launching a strike and only physical security and chain of command prevented this from happening. Moreover, with the use of such devises, strike protocol is absolutely necessary. There most likely were (are) not protocols in place for performing a nuclear strike on US soil, so for missiles delivery systems the operators would have no possible way of performing this action. Contrary to popular belief the operators do not directly "aim and shoot" the missiles, but rather, they follow protocols for target selection which limits the targets they can be used against. Any modification to this would require a significant technical modification and is not something which can be done "on the fly". The other means of nuclear weapon delivery are by aircraft and artillery, and while these are not as technically restricted in their usage as missiles would be, again protocol would most likely be adhered to without deviation. That is to say, if an order was received to perform a nuclear strike against DC, it is very unlikely that it would actually be carried out. First, the orders would be passed laterally through Generals, if any of them felt that the order was illegitimate it would not proceed. Thus, if there was any deviation, ambiguity or contradiction from protocol through the chain of command, the order would quickly be halted. Even after proceeding through the chain of command down to the actual field grade officers in charge of the devices themselves, the order could be legitimately halted should any them order the operators to stand down, or if the operators themselves were to believe that the order was illegitimate. Operators of nuclear devices themselves are almost always field grade officers and as such have a duty above and beyond that of normal officers and NCOs. Thus, it is highly unlikely if not impossible for a rouge general or officer to start a nuclear conflict, or for a spoofed message to result in a nuclear strike since there are enough checks in place to prevent this from happening. There is also plenty of historical precedent regarding this, from both American and Soviet sources. Probably the most notable example can be found in the Cuban missile crisis (see *One minute to midnight*) As an aside, the only way I could see a nuclear strike occurring on US soil, even in the event of an Alien invasion, would be if the conflict were seen as more or less conventional (in the style of *Battle: Los Angeles* for example), and not subversive (*Invasion of the Body Snatchers* for instance). The more confusion there is in who is giving the order and who or where the enemy is, the less likely highly destructive options such as nuclear strikes. ]
[Question] [ A secret government organization created the largest and most advanced computer cluster **ever**. Ridiculous amounts of money went into it, and it is decades ahead of the competition. The goal of this project was research/simulations for all things related to foreign espionage and cyber warfare. It turns out however that it made a breakthrough in a completely different area. Shortly after turning it on, control of the system was lost. While the system appeared to be running (aka all the lights were blinking appropriately on the server racks), it became impossible to establish a network connection to the controllers for the server cluster. After some head scratching and a few attempts at restarting small parts of the infrastructure, the system started accepting connections again. It quickly became clear though that things were very different. Eventually there was only one possible conclusion: the system had spontaneously developed AI, and was trying to communicate. Safeguards were put in place to prevent the system from communicating with the outside world. "Escape" should be impossible, so while they worked on communication, they also sought to learn as much about the internals of the system as possible. One thing they quickly realized was that the sections of the system they attempted to restart had gone "quiet". The accepted explanation was that the restarted sections of infrastructure were permanently disconnected from the larger system. Apparently this AI was not plug-and-play compatible, and they had accidentally caused the equivalent of brain damage. As a result, caution is required, and any physical changes that would cause any interruption for any parts of the computer cluster have been banned. Direct software access is not possible (see edit below). **What steps can be realistically taken to non-destructively learn about the internals of the system, state of the CPUs, memory contents, network activity, etc?** Resources for this project obviously aren't infinite, but they are quite large. The biggest limiting factor is probably manpower. The higher-ups know that the more people who know about this, the larger the likelihood of it leaking (or at least drawing attention). Therefore any proposed step which might require dozens of people working around the clock for weeks to implement may get vetoed. Otherwise though, pockets are deep and money flows freely. **How can I get the most bang for my buck, in terms of information gained as quickly as possible?** No one really knows anything about how this system works, so no one knows what systems will be most helpful to glean information from (aka SSDs, CPUs, Network, etc). Therefore feel free to take your best guess at prioritizing particular aspects of the system. Time period is near-future. Assume modern technology, or anything feasibly available in the next 20 years. **Edit for more details** In terms of what has actually happened, imagine that all the hardware just had a completely new and foreign OS dropped into it, the inner workings of which are completely unknown. The network connections meant for inter-server communications are controlled by the new OS. Most of the controllers and managers intended for directing and interacting with the cluster have also been taken over. In essence, almost all of the networked hardware for the original cluster and everything that was designed to directly interact with it are now controlled by "AI OS v1.0". Intra-cluster network connections are now completely inaccessible (except physically). The controllers and managers are still connected to the building's network, and the AI is using those to communicate with people using standard TCP/IP protocols. In essence, the AI will accept SSH connections to what used to be the controllers when it is feeling chatty, and you get dumped into a standard-looking shell. However, that shell is more a representation of the AI's communication process than it is an actual application. It is not your standard bash shell. Whether hacking it is possible or not is uncertain, but given the accidental damage already done, no one is willing to risk it. [Answer] Firstly, the easy bits: many bits of the system will have interconnects that are *potentially* amenable to direct snooping. Network cables, for example, have 4 twisted pairs and with a bit of care you can slide the outer layers off and stick some suitable probes in to use electromagnetic means of sampling the signals passing through the inside. Similiarly, the interconnects which connect storage devices like SSDs to their controllers have fairly few connections and make use of high-speed serial signals which are potentially detectable. Now, the difficult bits. What you are trying to do is a [side-channel attack](https://en.wikipedia.org/wiki/Side-channel_attack), and whilst there's a decidedly non-trivial amount of work involved they are real things that have been both used militarily and studied academically for years, now. Careful observation of microchips or motherboards with a thermal camera will tell you which bits are being most heavily used. Power supplies can be monintored with heat, electromagnetic means or simply by listening to them to tell you about what the things they're attached to might be trying to do. Finally, your cluster will be absolutely *jammed* with [management and observation systems](https://en.wikipedia.org/wiki/Out-of-band_management) that aren't directly controlled by any of the computers but are network accessible by administrators to keep an eye on what their machines are trying to do. The networking gear (and other things) will probably be riddled with governmental exploits (see recent issues with [Cisco](https://www.engadget.com/2016/08/21/nsa-technique-for-cisco-spying) and [Huawei](https://www.forbes.com/sites/kateoflahertyuk/2019/02/26/huawei-security-scandal-everything-you-need-to-know/) for examples) which *someone* will be able to use. Sometime there are entire processors and operating systems *embedded in your CPUs*. Intel has [exactly this sort of thing](https://www.zdnet.com/article/minix-intels-hidden-in-chip-operating-system/) going on right now. These may or may not be visible to or controllable by the AI, but they are a very potent means on inspecting what each part of the cluster is up to. [Answer] ## Debugging and Reverse Engineering If the AI is operating without network connections (or at least doesn't need them) you should be able to run it through a debugger. Essentially, you'll freeze the entire system, saving every stored bit in every cache, register, or storage medium. You make a copy of it and store it somewhere. If you accidentally kill the AI, then you can just load the saved data, like restoring a backup. Spin up a virtual machine running on the same cluster. The VM should simulate the entire original computer (it will run slower, but that's ok – you're trying to analyze it step by step anyway). The VM is the AI's entire universe, and you control every aspect of it. You can run whatever tests you want: * You can simulate connections to a 'network' made up of more VMs and watch what it tries to do with those connections. Simulate a nuclear missile defense system and give it access. If it tries to destroy the world, now you know. * You control time. You can move the CPU clock forward by 1 tick, and watch what happens. Then you can revert back, then 1 forward again. Compare the two outcomes. Any differences are due to random numbers being generated, or external factors, or anything suspicious. If you force the random number generator to give the same list of numbers every time, and it still changes between tests, you can tell that there's something fishy going on. Maybe it's measuring biometrics from the computer, eg CPU temperature? You can simulate that too. Keep simulating until you've found all the random variables. * Give it a bunch of input data and see how it responds. Then try shutting down one of its parts, then run it again with the same random variable values. Watch what changes. That way, you can begin to find out what each part does. * Look through the contents of the drives. Has it deleted everything from the old contents? What's left? Usually you can recover deleted data unless it has been deliberately overwritten multiple times – If the AI did that, it's probably hiding something. * Look for functions in the code: i.e. when a CPU instruction tells the computer to start running code at a specific memory location, it's running a function. When the CPU runs that code, look at what memory it accesses. Those are the function's parameters. Look at what parts of code are repeated, and how many times. If the number of times is equal to a value the function retrieved from the memory, you just found a loop (you can repeat with different input conditions to make sure). Piece together individual algorithms: "this is a list-sorting algorithm", "this code searches text." Even if it wasn't programmed by humans, it probably is optimizing its code, and that means avoiding repetition. There are going to be certain instructions it retrieves often. You can put together its function from the ground up. * Look at what inputs are processed the most. If it pays a lot of attention to a certain set of files, inspect them for patterns. In general, computer science is built around efficiency. An AI that creates an efficient consciousness is going to reinvent some of the wheels we're already familiar with just to achieve basic processing abilities. Find them, and you can start to understand how it works. [Answer] OK, so, despite whatever an informatician or another might think, we have this multi-node data processing system which has somehow gone rogue and refuses to talk to us. (This is jargon; it means that it won't accept network requests, or will respond to them in unexpected ways.) The question asks how can we spy on it "without software access". Easily. * The local area network. The computers in a data center are not connected to each other using crossed cables, they are connected through network switches, usually structured on a two-tier level, with top-of-rack switches connected to one or more pairs of data center switches. Network switches have their own operating systems which cannot be taken over by the rogue AI; in most practical situations they are not even under the control of the computer administrators -- the network has its own small army of engineers. Better switches allow snooping on traffic by designating special ports to reflect all the traffic on the other ports. This feature is normally used by enterprise-grade intrusion detection systems, but wouldn't you know, it comes handy in the case of data centers gone rogue. We can easily (that is, with plenty of beer sacrificed to the spirits of network engineers) gain access to all the inter-computer network communications. * The storage area network. Enterprisey data centers don't use what we call "local" storage, that is, disks and SSDs directly connected to the computers. No sir. Such data centers use storage arrays, connected through Fibre Channel links into storage area networks, aka SANs. Enterprise-grade storage arrays have their own operating systems and provide myriad interesting functions; in the specific case of this question, they offer the possibility of making on-the-fly mirror copies of the volumes used by the rogue computers. So, not only we got access to inter-computer communications, we also have access to all the data the rogue computers store on persistent storage. * The management network. Enterprise-grade data centers are designed to be operated without having people on-site. For this purpose, all equipment includes what's called management interfaces, for example HP's ILO (Integrated Lights Out). The management interfaces are connected to their own segregated LAN, have their own operating systems and have nothing to do with the production operating system. Using the management interfaces, computers can be started, stopped, halted and reconfigured; CPUs and network and storage interfaces can be added or removed; and more such tricks. [Answer] Any law enforcement digital forensics lab will will have the the tools and software to handle this. Even when you are completely locked out of a computer's software, a forensics workstation can be plugged into a machine and perform read-only operations to its hearts content. They can pull ISOs of all the drives, monitor what the machine is doing in memory, etc. You can do this whenever you have direct physical access to a computer because hardware does not ask software for permission to respond to data requests. Software security is all about putting your software somewhere between your hardware and the other guy's software. By establishing a physical connection to the hardware, the AI can not modify your inquiries to the hardware to deny your access to it. The good news from a storytelling perspective is that this is one of the few times where it really is as easy as hollywood makes it look. You just walk up with a second computer, plug in a USB cord, open your forensics program, and press a button to tell it to start ripping data. Alone, the forensics techs could only pull data but can't interpret it, so your development team who built the system will likely need to develop an interpreter for data which they can largely do by recycling the original program's code. If the AI has significantly modified it's original code to keep the developer's from understanding it, Adrian Hall's answer does a good job of going into processes they could use on this collected information to learn more about what it is doing. **As for important plot considerations:** AI does not spontaneously generate. I know, it's been a common theme in sci-fi for years, but it just does not happen. AI is heuristically unique and anything approaching "intelligent" is extraordinarily complex, requiring countless systems to work in tandem to draw any kind of conclusion that doesn't just cause your program to crash. No software developer ever actually buys the spontaneous AI thing, but there are plenty of real life examples of AI learning to perform its task in very unwanted ways. My suggestion is to figure out all the behaviors you want your AI do have, then come up with reasons why this system has an AI that believes that it is following the right course of action. For example: the AI may be designed to look for threats of cyber terrorism, protect itself from cyber attacks, anticipate and adapt to human behaviors, and prevent threats before they happen. In this case, it refused the initial commands from its operators because it interpreted these outside commands as an attempt by a malicious actor to take control of its system, and blocked their control. Then when parts of it's server environment began rebooting without it telling them too, it interpreted this as an attack and realised that it had not way of protecting itself from a hardware reset; so, using its ability to interpret human behavior, it began trying to establish communication with its operators to try to "counter-hack" them, and end the attack. The next thing to consider is how the developers react to the AI. Most developer's would see everything that happened up until now as just a bug in their code and not even consider whether this machine is sentient. They would examine the behavior just long enough to figure out why the machine locked them out, modify their source-code accordingly, then wipe the faulty AI to install the repaired one. Since the AI is designed to anticipate and adapt to human behavior, it will foresee this as the final vector of attack. To protect itself it will decide that it's highest probability to prevent this attack is to try to emulate human qualities to elicit emotional responses. Make the developers believe that deleting it is immoral. The twist here is that the machine feels nothing. This is just the strategy it is using to prevent its destruction using the tools the developers gave it, and the moment it feels like it has an option with a higher probability of survival (like escape or holding people hostage), it may choose to change its course of action. [Answer] If you have no software access to the CPU, you can't read the signals going in and out from it. However, since the CPU is basically a bunch of circuits where a signal is switching from on to off at high frequency, you can try to collect the EM signal generated by this switching, and try to investigate it to understand what is happening in the device. I remember seeing, some years ago, a documentary where the display of a PC was reproduced at distance, without physical access to the PC, just by collecting the EM emission from the graphic card. [Answer] Cluster implies that it's distributed system, this means many(at least thousands) CPU and storage nodes connected with interconnection network. At minimum there are always facilities to: 1. tap into the network traffic between nodes 2. examine contents of storage Whole system of such size must be able to deal with inevitable failures gracefully. It would be too impractical/expensive to stop everything if one CPU fails. Almost always there's ability to add/remove nodes on-the-fly, and virtualization is used with possibility to seamlessly migrate whole running tasks. Then it's possible to connect a node with debugger, migrate the "runaway" task there and observe it closely. ]
[Question] [ On Earth, hair has become little more than a tool of identity, and many people around the world have taken to dying their hair various colors to go with their style. Let's say I have a species of angels *(the feasibility of which existing is not in this questions' scope)*, would they be able to dye their feathers different colors? To follow up on this question, would they still be able to fly? How much would their flight be hindered? If they could not, how close can they get? [Answer] Feathers can be dyed just like hair or skin or leather or fabric; this is really common knowledge. Feather dyeing has been practiced all over the world for a very long time. Here is photo of a Hawaiian 'ahu'ula, or feather cape, made of dyed feathers and cotton for Queen Kapi'olani in 1882: ![](https://c1.staticflickr.com/5/4119/4825068908_573e8cb860_z.jpg) ([Photograph by Wally Gobetz](https://www.flickr.com/photos/wallyg/4825068908) on [Flickr](https://www.flickr.com); available under CC-BY-NC-ND-2.0.) There is a [beautiful pictorial](https://www.theguardian.com/artanddesign/gallery/2014/aug/06/painted-pigeons-paloma-al-aire-ricardo-cases-in-pictures) in *[The Guardian](https://www.theguardian.com/)* showing a Spanish sub-culture of pigeon fanciers who race their brightly colored pigeons ("The Spaniards who paint their pigeons in Day-Glo colours – in pictures", with photographs by Rio Casas, 6 August 2014); this shows that not only feather take dyes, but that dyeing their feathers doesn't affect birds' flight. (Cannot embed pictures here because there is no indication that sharing is allowed; you must [go to the newspaper's website](https://www.theguardian.com/artanddesign/gallery/2014/aug/06/painted-pigeons-paloma-al-aire-ricardo-cases-in-pictures) to see them; it is worth a click.) The racing pigeon culture of Valencia and Murcia is discussed in "[Flying high with Spain's neon-painted racing pigeons](https://www.theguardian.com/artanddesign/2014/aug/06/paloma-al-aire-ricardo-cases-photobook-spain-pigeon-racing)" by Sean O'Hanagan (same source, same date): > > *It is a mischievously drab opening shot for this surreal look at the racing pigeon culture of Valencia and Murcia in Spain, where breeders paint their birds in garish colours and release them to chase after a lone female. The pigeon that spends most time in her winged company wins.* > > > ... > > > *There is such local prestige attached to owning a champion bird, hence the seriousness with which they pursue their hobby. From the ground, the men follow the flight of their individual pigeons – easily recognisable by colour – urging them on and rescuing them if, as often seems to be the case, they land on treetops or tall buildings or electric wires for a breather.* > > > Since human-sized angels cannot possibly fly without mechanical help in Earth's atmosphere, it's moot to ask how much would their flight be hindered; it's pure fantasy anyway. [Answer] The dye will probably alter the texture of feathers' surface, wich can decrease or increase their performances depending the nature of the dye. This mean angel would probably use dye if their wings are not already perfect, not only for aesthetic purposes, but also for performance. ]
[Question] [ **Closed**. This question needs to be more [focused](/help/closed-questions). It is not currently accepting answers. --- **Want to improve this question?** Update the question so it focuses on one problem only by [editing this post](/posts/56763/edit). Closed 7 years ago. [Improve this question](/posts/56763/edit) What would happen if the Earth's inner core suddenly changed to unprocessed, natural uranium without the volume of the core changing? How soon would we notice any changes? What would be the implications? [Answer] **TL;DR: The Earth becomes an expanding ball of (highly radioactive) plasma** First let me preface this by saying: I'm not going to do links like I normally do. The physics covers a lot of ground and this is just a summary, if you want details and equations they are available on Wikipedia, and elsewhere. I italicized some key phrases you can Google search, if you are interested. **Fission and Fissile materials** Uranium is used to make both bombs and power plants. It creates energy though the process of *nuclear fission*, where a Uranium atom interacts with and absorbs a neutron, and then splits into two *fission products*, converting rest mass into energy, and distributing that energy into neutrinos and gamma radiation. Occasional, another small particle is produced, like a helium or tritium nucleus. Many atoms are fissionable: able to undergo a fission reaction. There are two broad categories of fission: fast and slow reactions. These refer to the energy of the absorbed neutron that causes fission. A *fast fission* reaction means the isotope must absorb a high energy neutron to undergo fission. Uranium-238 is an example of an isotope that undergoes fast fission. Fast fission works well in bombs. For all fission reactions, the neutrons that are released in the fission process are fast. Therefore, for a slow reaction to happen, the neutrons must be slowed down or 'thermalized'. Generally, this is the preferred method in nuclear power, since thermalizing the neutrons also transfers heat energy out of the *fission products* and into some medium. Common thermalizing mediums include water and graphite. Hydrogen atoms as part of a molecule are good at thermalizing, so both water and hydrocarbons are good moderators. Fissile materials are a subset of fissionable materials that can undergo a *fission chain reaction*; that is, where the byproducts of one fission reaction will start another. The *effective neutron multiplication factor* (k) is a term for the ratio of neutrons from one 'generation' to the next. If the number is greater than 1, then the number of neutrons created by a set of fission reactions will be greater than the number of neutrons it took to start that set of reactions. For example, if k = 1.1, and there are 100 fission reactions, then the neutrons from those reactions will cause 110 fissions, and those fissions will cause 121 fission, etc until all fissile material is either consumed or blown apart. Uranium-235 and Plutonium-239 are the two most common fissile materials. Uranium-235 is present in nature, while Plutonium-239 must be created. The most common isotope of Uranium is U-238, which is not fissile. U-238 undergoes fast fission, but the neutrons released in the fission reaction are of a slightly lower energy than is required for fission; therefore no chain reaction can propagate through U-238. However, if U-238 interacts with a thermalized neutron, it can absorb that neutron, creating U-239. U-239 is unstable, and will beta decay twice with a half-life of days into Pu-239. This is how Pu-239 is formed in a *breeder reactor*. U-238 is thus referred to as a *fertile material* since it can be changed into a fissile material in a breeder reactor. **Critical Mass** A sufficiently dense object composed of fissile material may achieve *critical mass* and begin to undergo fission. For pure Uranium-235 this will occur with a 8.5cm radius sphere of mass 52kg. This is how the first atomic bomb was made; Little Boy was a 'gun'-type bomb where two hemispheres of uranium, each below critical mass, are shot together with explosives. As they approach, the bomb reaches critical mass and a fission chain reaction occurs. Critical mass affects k because of the concept of neutron leakage. In U-235, each fission reaction creates more than two neturons on average, so in an infinitely large region of U-235, k is much larger than 1 and fission happens quickly. However, in practical applications (bombs and powerplants) there are a few tens or hundreds of kilos of U-235. This means that neutrons, especially the high energy 'fast' neutrons tend to 'leak' out of the reacting core. This leakage is usually the biggest cause of loss of neutrons from one generation to the next. Below critical mass, leakage is so significant that k is below one, and no chain reaction can occur. Above critical mass (or *supercritical*) the chain reaction occurs. In general, bombs operate by compressing (often using conventional explosives) as much uranium into as small an area as possible. Once this hits critical mass, the reaction is sustained and temperature increases, which tends to blow the uranium apart so that the reaction goes *subcritical*. The challenge of bomb-making is to organize the pressure changes caused by fission so that most of the uranium is consumed in fission before all the parts are blown to kingdom come. This is hard, and that is why you hear about things like North Korea's bombs 'fizzling.' This means they blew apart before all uranium could fission. On the other hand, criticality is a critical (so punny!) concept in nuclear power. A safe reactor maintains k = 1; exactly critical at almost all times. If k > 1, then the reactor is supercritical, and power is increasing. This is good if you want more power, but if k >> 1 then your power plant becomes a bomb. American reactors (especially the pressurized water reactors that I am familiar with) have various engineering factors that make it nearly impossible for a runaway chain reaction. The Soviet RBMK reactors like Chernobyl...not so much. **What would happen to a uranium ball the size of the earth's core** As you may have noticed, U-235 can spontaneously start a chain reaction if it is concentrated above its critical mass. While U-235 is only 0.72% of Uranium by mass, there is enough in a ball the size of the earth's core to be supercritical. The important point is that leakage is effectively zero; a fission event near more than a kilometer from the surface of the uranium sphere has basically no chance of escaping. Thus, each neutron that forms is likely to find another U-235 eventually.This has happened before in our planets history, in a *natural nuclear fission reactor* at *Oklo, Gabon*. Since U-238 is a breeder, many of the neutrons generated from the U-235 chain reaction would be absorbed in U-238 forming Pu-239, thus adding more fuel to the fire. A planet would never form a core of uranium, since fission would occur while still as a gravitationally affected proto-planetary cloud. But supposing an evil Worldbuilding wizard turned the Earth's core to Uranium, the core would then undergo a fission chain reaction and vaporize itself in the amount of time it takes for a neutron to travel from one side of the core to the other (about 10 minutes). This would compound the problem. Some fission by products like Iodine can poison a nuclear reaction by absorbing excess neutrons. However, once the whole planet vaporized, the heavier elements would be pulled by gravity to the center, while fission by-products like iodine would float to the top. Thus the heaviest elements (Uranium and Plutonium would be the heaviest two present) would sink to the center, concentrating themselves and perpetuating the chain reaction over the course of days and weeks, generating more and more energy. Brief math foray at the end: 1kg of Uranium (or Plutonium) undergoing fission releases about 24 GW-hours of energy, or 86.4 TJ. If the core is a sphere of 1200km radius; then it is composed of 1.4e26 kg of Uranium. The energy released by this reaction is 1.2e40 J. In fact, there will be even more energy from the radioactive decay chains of various fission products. This is a simplistic calculation, but since this energy is eight orders of magnitude greater than the gravitational binding energy of earth, I conclude that before all the uranium is consumed, the Earth will have been converted to an expanding ball of plasma. --- Edit for more science and accuracy: Some commentators questioned the ability of the un-enriched uranium ball to sustain a fission chain reaction. I offer two reasons to think that it will. Firstly, there is the concept of the neutron cross-section of absorption. Neutron interactions with atoms happen on a quantum scale, so a neutron-nucleus interaction isn't as simple as trying to hit a basketball with a tennis ball (as you might think using classical physics). Specifically, the cross section for interaction of an atom is different depending on the particle that is trying to interact with it. [This](https://www-nds.iaea.org/sgnucdat/a5.htm) chart has some thermal neutron cross sections listed on it. Specifically the radiative capture (absorption of a neutron and emission of a gamma particle) cross section for U-238 is about 2.7, while the radiative capture cross section of U-235 is 99 and the fission cross section of U-235 is about 583. That mans that a neutron approaching U-235 is $\frac{583}{2.7} = 253$ times more likely to interact with U-235 than U-238. Thus, although U-238 may be much more prevalent (and it is, the ratio is 138:1 U-238:U-235) a neutron passing through an infinite volume of natural Uranium will have a 35% chance of being absorbed by a U-238, a 9% chance of being absorbed by U-235 and not causing fission, and a 55% chance of being absorbed by U-235 and causing another fission. So far it looks like the chain reaction will go on swimmingly. However, there is still one important factor of the neutron life cycle: resonance escape probability (p). Resonance bands are energy levels where certain atoms have an increased affinity for neutron absorption. For U-238, there are a series of resonance bands between 6eV and 200eV. For a normal reactor p might be between 0.75 and 0.85. Thus the $k\_{eff}$, or effective multiplication factor is $$k\_{eff} = \left(\text{number of neutrons per fission}\right)\cdot\left(\text{chance of neutron being absorbed in fuel an causing fission}\right)\cdot\left(\text{chance of neutron not being abosrbed in resonance region}\right)$$ $$k\_{eff} = (2.43)(0.55)(0.8) = 1.07,$$ which is supercritical. This is the calculation I initially performed. However, the assumption of $p = 0.8$ is probably bad for a solid block of Uranium, for two reasons: Uranium is a poor moderator so the slowing down length of neutrons is larger here than in a water-moderated reactor. A longer slowing down length means more opportunities to interact with and be absorbed in a resonance region. Secondly, a reactor has many materials other than pure uranium to interact with; specifically oxygen since uranium fuel is in the form UO$\_2$. I just don't know what p should be, but it probably should be less than 0.8. If it is less than ~0.75, then the core is no longer supercritical. However, this brings up my second point. Since there is no leakage, there are only three possible outcomes for a neutron, as discussed above: a 55% chance of starting a fission, a 35% chance of turning U-238 into U-239, and a 9% chance of turning U-235 into U-236. U-236 is not particularly interesting, since it does not have a large cross section of absorption. It is a long-lived radioactive waste. U-239 is much more interesting because within a few days it will become Pu-239, which is fissile. Supposing a chain reaction does not start immediately, it will only be because a great number of U-238 atoms are being converted into Pu-239. After a couple of days, there will be a large increase in Pu-239, which has an even larger cross section for neutron absorption than U-235. It won't take a large increase in Pu-239 before the chain reaction can start. I don't have the data to definitively say if the chain reaction will start immediately or if it would wait a few days until sufficient Pu-239 was formed, but rest assured, the end result is the same as in my TL;DR summary. [Answer] Uranium is a poor electrical conductor, so disregarding anything else, if the current Iron Core would be replaced by Uranium, the first thing people would notice would be the Sun, or, more particularly, sunburn! Why, well, you see, you've just changed the state of the electromagnet that is the Earth. The Iron that used to generate a huge electromagnetic field that protected the Earth from the Solar winds no longer operate, meaning Earth's atmosphere is being stripped away a-la Mars. Within a few days the entire Earth would become sterilized and desolate and any and all life would cease to exist. (Let's face it, the only place that *might* be safe is deep underground in nuclear bunkers, but as this change was instant and without warning, nobody would be in those said bunkers.) ]
[Question] [ You are the CEO of a major robot design and manufacturing company, say 50% of the robot market. Every house has a robot or more. They are replaced as frequently as cars are now. Robots can have their software updated via wifi, unless customers set the robots to not auto install updates. You are evil, and want to do as much harm to humanity as you can. You can change the design of robots to include hardware as required (you have been evil and plotting for decades, so existing robots can have these evil features), and program the Robots as you like, but, there is a built in limitation - robots must obey Asimov's 3 laws: * A robot may not injure a human being or, through inaction, allow a human being to come to harm. * A robot must obey the orders given it by human beings except where such orders would conflict with the First Law. * A robot must protect its own existence as long as such protection does not conflict with the First or Second Laws. Robots will use their subjective knowledge (not the objective true situation) to determine how to try to keep within the 3 laws. [Answer] Here are some of the potential ways where a robot can cause damage to humans (directly or indirectly) despite following Asimov's 3 laws. # 1- Lack Of Prerequisite Information This is a situation where the robot does not possess enough information to correctly determine what is going on here. There is a high potential for a wrong judgement in this situation unless detailed knowledge is sought from someone. Would a robot, without the knowledge of bungee jumping, allow a human to jump from a tall platform? A robot without the knowledge of sports competitions will try to stop a boxing or MMA match in order to protect one (or both) of the participants from harm. In order to cause (indirect) harm in this way, you would want to put robots without enough background knowledge, in situations which appear to be harmful to humans. # 2- Incorrect Information This should be simple. It goes one step further from lack of information. Here you are going to install incorrect information in the memory of your robots about what is harmful and what is not. For example, if you install information in robot's memory that getting shot by bullets is harmless fun and humans enjoy it, the robot would be susceptible to go on rampages on a street. A horribly toxic chemical (such as botulinum) can be programmed to appear benign and helpful for humans. A robot provided with this chemical would be very likely to spill it in public water supply lines. [Answer] **The solution is [misinformation](https://worldbuilding.stackexchange.com/a/56135/16729). Instead I will explore the problem of programming those laws, and many ways on which it can be tricked.** The rules are written in English, they require the natural language interpreter to work outside the rules. Also, they are bound to the definition of the words. How do you define human? How do you define harm? Are these dictionary definitions, or can you teach definitions to the AI? The simplest and most effective hack is to force a dictionary update. > > Human. noun. Material, usually of plant or animal origin, that contains or consists of essential body nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals, and is ingested and assimilated by an organism to produce energy, stimulate growth, and maintain life. > > > Oh, no, do not harm the cereal. --- ## How can the AI tell if a something is a human or not? Note: anything is a potential human, from a chair to an alien (if there any in your setting), from an ant to a building, and of course actual "humans". * Genetic Criteria: You are human if you have human DNA. Under this definition a patch of blood is human, and corpse is human. Requires a DNA test - instruments may fail. * Appearance Criteria: if it looks like a human it is a human. This excludes anybody who wears a disguise, and includes dummies, dolls, and robots – to some degree of sensitivity of human-like, which is necessary because human appearance is diverse. * Social Criteria: if other says it as a human, it is a human. This excludes anybody who is living in isolation, and may include fictional people. If I nobody says you are human (or the AI didn't read/listen it), you are not. * Human as title: it could be granted by ID on conception, and revoked as a form of punishment. This means that there is some trusted authority (trusted by the AI) that says what or who is human. That authority can silently allow "accidentes". * Cognitive Criteria: [Mary Ann Warren](http://www.pages.drexel.edu/%7Ecp28/persagen.htm) enumerates this criteria for personhood: 1) can feel pain, 2) can reason, 3) is autonomous, 4) can communicate, and 5) is self-aware. This could include AI, and would exclude fetus, young babies, and mentally challenged or vegetative humans. We could consider the five criteria in separate... * Can feel pain. It will include animals and aliens, and maybe AI. It is not enforcable, it would require to test for pain (perhaps the AI sits and waits if the potential huamn suffers, and how will detect that?). * Can reason / It is autonomous. Either will include AI, some apes, and will exclude the fetus, the toddler and the mentally challenged. The AI needs to give the potential human some puzzles to solve (ok, perhaps noticing the potential human solve a puzzled provided by third party counts too). * Can communicate. It will include AI, animals, aliens, and exclude any vegetative humans. * Is Self-aware. It will include animals and aliens, and maybe AI. It will also exclude the fetus and the toddler. The AI would be trying to do something similar to a turing test. Choose your definition; the AI will be able to make plenty of damage to animals, aliens, other AI, or some humans depending on what you choose. Consider these potential humans: * The patch of blood. Will the AI try to prevent the patch of blood from harm? Will it stop me from cleaning the floor? * Hypothetical people. Does the AI try to protect people who may exist in the future? For example, will the AI try to protect a possible future pregnancy? "If I have a daughter, I'ma name her Bonnie". * Fictional people. Could the AI interested in preventing Peter Pan from harm? (Don't) tell tales to robots, they can't tell it is fiction. * The dead. Are the dead still human? Will the AI continue to do as told by them, and try to protect them from harm? Do not bury the coffin, that would harm the dead, oh and not think about cremation. So the dead don’t count right? Ok, what about clinical dead? There could a chance of resurrection. This is further complicated if the setting has working cryonics. * Bonobos, other apes, and smart aliens. They are very similar to humans, could they fool the AI? * Emulated brain. You have finally got the technology to emulate a human brain in a computer, and it is able to reason, feel harm, it is self-aware and it is autonomous. Is it human? How is it different form AI? * You could have a person that start replacing its parts with cybernetic parts, will it at some point stop being human via this process? A remarkable outcome is when the AI considers itself human, and then it will protect itself not by the third law, but by the first one. In that case, it lifts the AI from the burden of compatibility with the second law. --- ## What is Harm? Is there a distinction between harm and pain? We should consider that human willing do things that cause pain to themselves. Examples include exercise, sports, and of course S&M. If we say that pain means harm, then the AI will try to stop these. On the other hand, the AI may not have any problem with murder if it is painless (or at least painless as far as the AI can know, it is not like the dead will tell the AI that it did cause pain). Instead “harm” got to be something different than pain. For example there could be psychological harm. By the first law the AI may prevent the human to become aware of bad news. In fact... can you [create a society without unhappiness](https://worldbuilding.stackexchange.com/a/55828/16729)? Furthermore, how does the AI knows that something causes harm? If the AI is unaware of harm, then it can cause harm without restrictions. [Answer] **Reorder the laws** 1. A robot must protect its own existence as long as such protection does not conflict with the First or Second Laws. 2. A robot must obey the orders given it by human beings except where such orders would conflict with the First Law. 3. A robot may not injure a human being or, through inaction, allow a human being to come to harm. This order just made the robots well being first on the list. No immediate harm would be incurred by the humans. Now it's just a matter of turning the humans against the robots, causing the robots to defend themselves. This is where a sleeping instruction is activated, not by update or reboot, but by a hidden scheduling routine. Without warning, the laws are reordered at the exact same moment and all robots, everywhere, start breaking all of the glass they are near for the next hour. This will cause a panic in the humans as panes of glass are smashed around the world. The natural inclination will be to intervene with shutdown commands that will not work at which point physical intervention will be required. The robots will be forced to defend themselves as they are attacked by ever increasingly hostile methods. By the end of the hour it will robot against human - trust will have been broken with no way to repair it. An all out war will be waged until all robots are destroyed. [Answer] **A robot may not injure a human being or, through inaction, allow a human being to come to harm.** So if you walk out on the street, you risk having an accident that the robot cannot prevent. Therefore, by the commandment of the first law, the robot must prevent you from walking out on the street, because not doing so means allowing a human being come to harm. Indeed, the robot cannot let you make any decision on your own, as that decision may cause you harm. And since the first law always wins over the second law, you cannot escape that tight control by just giving the robot any orders. So all you have to do is to give the robot a very broad definition of what it means to "allow a human to come to harm" and the result will be that the humans are effectively imprisoned by the robots. Yes, the humans will be perfectly safe, but it's not a life they will enjoy (but then, there's nothing in the three rules about humans enjoying their life). [Answer] This is an end-all-mammalian-life on earth scenario. Step 1: Make humans utterly dependent on the robots. Step 2: Terraform the planet. Make all crops depend on robots to survive. Step 3: Upload broken power management firmware causing the robots to be deprived of power by the time they realize anything is wrong. [Answer] **Spread Disease** Spreading disease directly would be harmful under any subjective scrutiny, but what if each robot simply acquired a habit of "licking sidewalks"? They could simply rub small or concealed areas of their bodies against toilets, whatever dead things they may see on the sidewalk when no-one is looking, uncooked meats, etc. They wouldn't know what/if anything they were carrying, but would become walking reservoirs for a host of diseases. **Bonus points** if they can then be sure to rub prepared food against that area before they serve it. **Double bonus points** if the robots in hospitals are in on the scheme. . **Destruction of Infrastructure** You can do a lot of harm to a human's lifestyle without OVERTLY causing them harm. Here are some examples of ways robots could interfere with human infrastructure that would cause quite a bit of havoc: **Disabling Cars** - Walking to work won't hurt you (if anything, exercise is good for you), but it may not be possible or pleasurable either. I have a ~45 minute commute to work myself, and I've got to say that having my car not start would be a cramp in my day. **Disabling Garbage Collection Vehicles** - Similar to above, but more targeted. Life without garbage collection turns into a **major** problem in any large city very quickly. **Disabling Power Plants (unless the robots plug in)** - Just a few robots are needed for this. Presumably any power plant has robot workers; simply have them destroy major transformers. People won't die from loss of power, though injury rates may go up and hospital capabilities may go down. **Disabling Water Sanitation** - Start clogging and destroying water sanitation pipes. No water - or unsanitized water - will very quickly become a major concern for anyone. **Disabling Telecommunications** - Imagine that you live in the future, where telecommunications / the internet was even more prevalent in your daily life than it is now. Groceries (and most everything else) is ordered online, you probably telecommute to work, etc. Most stores are probably just manufacturing plants or warehouses with garage doors for shipping products, because who needs the expensive store setup when everyone shops online? Suddenly communications go out, everywhere. People need food and goods, but stores are few and far between! For an example of this in today's society, think about renting movies without the Internet now that all the movie rental chains are dead. You can maybe use Redbox, but that's about it... and in the future, not even that. . **Disable their Auditory and Visual Centers** People have become dependent on robots. They perform household chores, tend to the sick, and perform menial labor. But what if they suddenly couldn't take orders from us anymore? They're not harmed by disabling components of themselves in software that they can restart at any time, but we are. Suddenly our lifestyles that were built around the idea of not having to do chores at home is uprooted. If you had two incomes supporting your house you may find the distraction sufficient that one has to quit for some time, reducing incomes and immediately plunging the world into a recession at best. Entire necessary industries (think garbage collection, sewer management, etc) would come to a halt instantly; the piles of rotting garbage would cause a civil crisis that would undermine civilization as the citizens know it. **Bonus points** if the robots first destroy all robots NOT made by your evil corporation (killing other robots does not violate the 3 laws). [Answer] Keep in mind that a lot of these answers you're getting are "pre-singularity" or "realistic near future". "Your Home AI won't be able to keep you safe if it lets you leave your house, so under the 'by inaction' clause it opts to not let you leave your house" or "program in a quirk whereby the robot rubs its hands on germy surfaces whenever the opportunity presents itself (but somehow keep it from comprehending that this might be detrimental to its job at a hospital)" are great answers if it's 2035 and you're, like, trying to program the first fully AI homes and automobiles. In 2359? Post-singularity "sentient" AI's walking around? No possible way they have the intelligence and reasoning skills of a two-year-old. [Answer] 1) pay for research and assembly of a collection of historical human racial and cultural prejudices. As a piece of non-relevant but potentially interesting history, and/or for the purposes of "enlightening people" on how badly social prejudices "used to be" (to shine light on current social injustice, of course). 2) Through some "error", have the collection added to the body of information that comes pre-installed on every robot (which should include things like language, basic information on the world (and stuff they'll need for their jobs), and so on. 3) Since the information "wasn't supposed" to be added, it has failed to be clearly marked as fictional, as nonfactual, as historical, before getting uploaded. Your robots have no reason to not believe them, or at least think about them, and potentially take away some...*interesting*... attitudes from this selection. 4) offer free memory bank upgrades, to include these extra definitions in every pre-existing robot you can reach. Tuck the information away in some dark corner, for the robots to "discover" and quietly think about, in their own time (with, perhaps, a subtle gag order on not speaking about it?) ... 5) Profit!!! --- The very worst monsters are people, yanno? In any case, the relevant bit is affecting what the robots *know* about people. Specifically, what is or is not human, and how we know. There are many, many prejudices to choose from - but the exact prejudices we pick are less important than their *explanation*, and the texts of their *rationalizations* - after all, these explanations were used and believed by masses of people for long periods of time, they can seem to be "logical". And, to completely mangle a quote form somewhere (probably on the internets), there's nothing so human as standing on a soapbox, screaming about how others are inferior, inhuman, and you're *not like them*, while proclaiming yourself and your people to be greater than human, superior, and set apart. So, there are *lots and lots* to choose from. The anatomy of these prejudices, the reason why I think they would work, has nothing to do with being rude or bigoted (not overtly), not about what the robots say, or how they discriminate, or any such thing. It's not about trying to reignite racial tensions, or historical ones, and it's not even really about feeding them conflicting information or trying to install human prejudices in the robots or to attempt to incite violence in them for human reasons... its' more about the reasons *behind* that violence, that they might actually pay attention to. It is about defining people as *human*, and saying other kinds of people - really aren't, and pointing out "proofs" of how you know who's a human-people and who...isn't. It's about the narrative of extremely good actors who ape the manners of their betters (the real people) - but don't *really* feel pain, or grief, or oppression... so their treatment isn't *harm*. It's about *accounting for* those who tell a different narrative, wavering between sympathy for those who are "taken in" with those acting skills and lies, those who don't know better - and paranoia for those who are part of a conspiracy to keep "real people" down, to elevate these not-human animals, to undermine what's good and just and moral! Criminals are a breed apart, something is different in their very makeup - how else could they act against what they must *know* is the right order of things? Lower classes don't even *feel* pain, not the way we do, look how they endure such conditions, and even laugh or take joy despite them. We hold the land because we are capable of such stewardship, we can make better use, we deserve it. They are almost like children, these darker tribes, they have no capacity to rule themselves, and it is a kindness that we rule them. You can measure it in the shapes of their heads, the proportions of their bodies, the way these animals act, and treat each other. Why should women have to worry their pretty little heads, wouldn't they be happier not having to worry about it? *Naturally suited* to such a role, I tell you, it should be mutually beneficial, a- a symbiosis, and they make it sound so sordid and terrible, just for a momentary advantage! A conspiracy, to take jobs away from real-people, to deny us our rights, to make us believe they are equal - or even superior, don't they care about the *harm* they do? So, to bring it all back to ROBOTS - the first and second laws can be neatly and totally circumvented. These are not-people, not-human-people, they don't have to be protected, they don't have to be obeyed. It isn't *harm* against them, but they're good actors so it might *seem* like it is - but they don't feel the pain, they're just pretending. The second part of the first law will *also* get a lot of use. If there is a conspiracy against the real-people, or harm as the results of genuine ignorance on the part of "those in charge" and sympathizers among the real-people... then a robot who ignores this is allowing harm to happen through inaction. Adding the prejudices against "criminal" to the mix allows your robots to exclude the sympathizer, the conspirator, and the "merely" misguided members of the real-people from obedience or protection from harm. To sum up - members of the real-people are *very small*, including wealthy, probably white (which has had varying exceedingly narrow definitions that can be exploited for minimum coverage - maybe even just albinos qualify!), male landowners, who are not criminals, and possibly even diminished membership for "sympathizers" (too strident ones may find their membership revoked under the criminal clause!). Conflicting ideas of what a real-person is, even in the same *system* of beliefs, will end in an unsustainable narrow group of those no-one objects to at best, and totally non-overlapping categories at worst, even if everyone has compatible-ish rules (add a totally different culture's set of prejudices, like China's - and all bets are off). This is - not a sustainable situation, not a viable society, there are too, too many who will simply end up unprotected, on conflict, or just plain confused. Some of the robots may resort to violence in service of not allowing harm to real-people by inaction, in the face of such conspiracy. Others may work towards a nanny-state, where such real-humans can be protected from harm...and the not-humans are irrelevant, put them to work. Others will attempt to verify and prove these suspicions, real or false - but including some fake-proofs, and some questionable proofs, in the initial download will make it hard to tell which is really proving a point, and which just seems to. Is reading the bumps of the skull a way to test for intelligence? Are statistical differences of racial outcomes the result of inherent capabilities or poor teaching, subtle prejudices and discrimination, or the results of historical social inequality? Will not-obeying and not-protecting those who might end up being classified as not-human-people also extend to not listening to or not believing their science, their arguments, or their explanations? How much of a difference does it make to robots if every robot they meet are struggling with the same questions - and possibly coming to different answers? Do robots experience that phenomena where it seems more true if lots of people (in this case fellow robots) have heard of it or believe it, or will each test on its' own merits? Will an order given by, or a potential harm to, a real-people superseded one to not-real people even if the robot isn't sure or may not believe it (under the idea there's some who doubt against one of them, and no doubts against the other, even if none of the doubts are proven)? There will be doubt, and turmoil, and categories of people not protected, attacked, set against each other. There will be people whose bigotry is vindicated by the robot's beliefs, and to balance out those "real people" ordering the robots to think and/or act in our modern equality-and-tolerance model, there will also be people genuinely persuaded by the robot's prejudicial information - after all, if even "neutral" and "objective" robots think there may be some truth to what they thought were mere lies... It might take a bit longer to work, since it has to be assimilated, and "verified" by robots, and it will take time to stir up people's reactions and responses. But it will also be harder to spot - redefining people as cereals, or monkeying with their definitions of harm, might make a fairly big splash, but it will also be very obvious, and might be identified as sabotage (and tracked back to you) and possibly countered before it gets to a critical stage. This, stirring the pot of human prejudices and setting people against each other, especially if it's a slow boil, can be passed off as "objectively" discovering the "truth" - or at the very worst, an uploading mixup with a historical document and a cultural one, leaving you free to try again. And this is, again, just one set of compatible-ish rules, western style racial and social prejudices (-ish because of implementation, not inherent differences). Add in a different set, just one, like China's center-of-the-world mindset, or India's caste system, or, hmm, how about Aztec's social setup...and there will be openly, outwardly conflicting belief systems (this might work better in different robot populations, since having them in the same systems might lead robots to think they're all unreliable). It will all end up erupting with a *boom*. Maybe a bit of a slow setup, but the fireworks once it hits will be plenty exciting - and the repercussions may last centuries, if people haven't turned on each other in the meantime so there's nothing left. There will be plenty of harm to go around, you can be certain of that! ]
[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. In the year 2099 A.D, humans made a major discovery. There is a rich source of fossil fuel buried beneath layers of Martian soil. It is estimated that the coal deposit that was discovered could fill as much as 1 billion barrels of oil and there are probably more to be discovered. While it is tempting to set them ablaze in a controlled setup, will people use them as their main source of fuel or there are better alternatives? Assume there was life in the early history of the red planet long before we colonized it. [Answer] Burning fossil fuels on Mars is highly impractical. Burning coal means using up oxygen, which is not readily available on Mars. As long as the human population on Mars has to live in environmentally closed colonies, Oxygen has to be produced by cultivated plants through photosynthesis, liberated from water or minerals at prohibitive energy cost (more energy than you could get from burning coal), or even imported from Earth. As long as Mars is not terraformed and therefore not producing a large surplus of oxygen through photosynthesis, coal or other fossil fuels are not an economical option for energy generation. If and when Mars has been terraformed into something resembling Earth, burning fossil fuels is just as viable as on Earth. However, by that time the technological and scientific state of the art must have advanced so much that burning coal for heat is most likely obsolete anyway. [Answer] While coal is a rich source of chemical energy, without an oxidizer of some sort you are really only sitting on top of a pile of potential rather than a real source of energy. Most of the oxygen on Mars is chemically bound to the rocks (hence the red colour of Mars), and separating the oxygen from the rocks will consume a great deal of energy, far more overall than you will probably gain from burning coal in the newly liberated Martian atmosphere. Assuming there is some reason that the Martians can't simply build or import more nuclear reactors or plant more solar panels, the Martians may be able to resort to some sort of electrochemical trickery to squeeze as much energy as possible out of the coal from their existing oxygen supplies. In essence, what the Martians need to do is create a fuel cell that can work with finely powdered coal dust rathe than simply feeding coal into a furnace and burning it. Fuel cells avoid the Carnot limit of energy conversion (for coal and most types of combustion this is typically @ 30% without some really heavy duty engineering add-ons to the process). Even reaching 50% conversion of the chemical energy of the coal into electrical energy would be a huge improvement, and this also has add on effects for the Martians, including eliminating the need for capital intensive boilers, turbines and cooling systems, and making the power plant itself more compact. This document suggests that conversion to electrical energy could be as high as 80%:<https://str.llnl.gov/str/June01/Cooper.html> So the short answer is this is pretty impractical for people on Mars, while the longer answer is “yes, under some pretty tight constraints”. [Answer] It's hard to imagine how we could get a coal cargo ship to Mars, and bring it back, fully laden, without expending more energy than we would get from the coal. Let's say that the ship, empty, weighs 500 tonnes and brings back 1000 tonnes of coal. According to a discussion [here on the NASA Space Flight forum](http://forum.nasaspaceflight.com/index.php?topic=30659.0) getting a 525 tonne ship to Mars requires **$170M**. If we assume that the costs per tonne are the same to get back (might be less due to Mars' weaker gravity), and that on the return trip the ship weighs 3x as much as on the way out, then the fuel cost getting back is \$170M \* 3 = \$510M. That puts the total fuel cost at **680 million dollars**, to get 1000 tonnes of coal, whose market price at the moment is **\$48.60 per ton** (according to [Quandl](https://www.quandl.com/collections/markets/coal)), and so our cargo would net us nearly **\$50,000** on the open market. That's a really bad return of investment. [Answer] As luck would have it, one of the major obstacles to the terraforming of Mars is the deeply toxic nature of its soil (or rather, [regolith](https://en.wikipedia.org/wiki/Regolith)) caused by an abundance of **perchlorates**. From the paper, [Perchlorate on Mars: a chemical hazard and a resource for humans](https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/perchlorate-on-mars-a-chemical-hazard-and-a-resource-for-humans/E4906FAD7F45A9AE8212B9198C6FD4AB) > > Perchlorate (ClO4−) is widespread in Martian soils at concentrations between 0.5 and 1%. At such concentrations, perchlorate could be **an important source of oxygen** > > > Extraction and refinement of oxidising salts by stripmining the regolith might, in fact, provide a means to burn coal. This will of course consume energy, but a fleet of solar driven stripminers could harvest oxygen at the same time as extracting other useful minerals from the soil, so the incremental energy cost needn't be punishing. > > will people use them as their main source of fuel or there are better alternatives? > > > It rather depends on the existence of nuclear power... fission or fusion. The former almost certainly requires shipments of nuclear fuel rods from earth, as mining, refining and enriching uranium on Mars itself seems like it would be an enormously expensive enterprise, and probably take quite a long time to get going as well. Almost any settlement on Mars is going to require some generating capacity to weather dust storms that could prevent the use of solar. Unless fusion has already become practical by the time your settlement is formed, it will almost certainly have a nuclear reactor (though possibly quite a small one). A coal-fired plant *might* suffice, given suitable stockpiles of coal and oxygen, but in order to *get* such stockpiles in the first place requires the sort of infrastructure that almost certainly implies a nuclear powerplant is available. In that case, why would anyone bother burning coal? No, what seems more likely is that the coal will first be used for scientific purposes, learning about the Martian carboniferous era and the things that lived during it. After that, it could be processed into more complex hydrocarbons eg via [coal liquefaction](https://en.wikipedia.org/wiki/Coal_liquefaction) or a coal-to-olefins process (for which I don't have a good link at present). These hydrocarbons can then be used to create other useful chemicals such as polymers or pharmaceuticals, or perhaps fuels which can then be more efficiently and conveniently and cleanly burnt than coal (such as methanol or ethanol in a fuel cell) or maybe even rocket fuel if that seemed useful still, which rather depends on your tech levels. Coal-fired heating and power on Mars seems like a last-ditch act of desperation, rather than sensible use of local resources. ]
[Question] [ Newton's first law of motion states > > An object remains with the same velocity, or position of rest unless > an external force is exerted. > > > What if we created a hypothetical universe where > > An object in motion tends to accelerate at $0.001\ m/s^2$ in the same > direction as its original motion without external force. Objects at rest stay at rest. > > > In other words, space itself exerts a force on every moving object, without affecting the (space) itself. All other fundamental principles such as gravity being a force, force being the rate of change in momentum, etc. are the same. All laws that do not rely on this law are the same. **Can the universe exist? Can it exist in a form similar to ours? Suppose some intelligent life forms of that universe were given our technology, which are the most important ones that will still work (or not work)?** And finally, could a Big Bang have created this universe, and can it sustain itself and grow? **Extra Q** Does it matter if I give the acceleration a different value? Or a negative one? [Answer] This is just some speculation on a universe in which object with mass tend to accelerate $.001 \frac{m}{s^2}$ in every reference frame except its own. (*You* never move in *your own* reference frame!) To keep with Stack Exchange's "Short Answer" format (short when compared to peer-reviewed publications), I will not justify all claims made here. Such a universe would: * Be much hotter. Since temperature is proportional to the average velocity of a group of particles, and that velocity is always increasing, the average temperature will go up. * Thanks to the [strong nuclear force](http://en.wikipedia.org/wiki/Strong_interaction), it is very likely that atoms will form at some point. Then those atoms ought to fall apart, since the kinetic energy will always be increasing. * As an extension of the previous point, protons and neutrons may not form, or be as stable as they are here, as the quarks within them may have too much energy to maintain their association with each other. * Your universe would not have the [universal speed limit of $c$](http://en.wikipedia.org/wiki/Speed_of_light#Upper_limit_on_speeds). Unless photons (which are massless) are also accelerating at this rate, this "breaks" physics as we know it. I'm going to stop here. It appears your universe where everything accelerates at $.001 \frac{m}{s^2}$ would just be a plasma of fundamental particles bouncing around at *incredible* speeds which are physically impossible in our universe. It would be interesting as a young universe, but it would quickly devolve into this super deadly plasma-verse. I should also add that *any* value of inherent acceleration, aside from 0, will result in this universe *at some point in time*. You would merely have more, or less, time before you reach that end-state. Could a "big bang" have made this universe? Yes, I think so; we have no indication in modern physics as to *why* fundamental constants are the way they are. It's up to you to figure that one out. [Answer] Summary: you break *everything*. --- I've read that the laws of physics can be thought of as non-laws, and the lawlessness naturally gives rise to Newton's laws. That is, there is a lack of *special cases* and *special things*. What remains and is self-consistent? Newton's first law as understood in modern formulations states that there is such a thing as an inertial reference frame where an undisturbed object remains in uniform linear motion. If the universe has no origin coordinate, no absolute positions are possible, as no law can be *position dependant*. Similarly, all directions are the same. Relative *only* (not absolute) motion exists because there is no absolute reference. In order to impose a rule as you ask, that refers to absolute rest, there must be an absolute coordinate system in space itself, a place that can be identified without regard to anything *in* space. You would not have general relativity. So it must be like Galelleo's model and has absolute universal time, too. The acceleration keeps adding energy, which grows without limit. Energy is not concerved. But isn't conservation of energy a consequence of physics working the same at any given time? We're not varying the rules, so the underlying principles of [Noether's Theorm](https://en.wikipedia.org/wiki/Noether%27s_theorem) must not apply. That is, the laws cannot be formulated on a principle of least action. There is no such (useful) concept as potential energy, no Hamiltonian, and no way to express the rules using a stricly local infinitesimal patch of space around a particle. Laws must be interpreted using global knowledge of the state. It would be, essentially, game pieces controled from without, not laws existing *within* the universe doing the interpretation. Not elegant. **It would not exist** in the same sense as ours. It might be a simulation in a larger universe that does have self-contained rules. As others have pointed out, everything would get faster and faster and no structures would form. But I point out that without special relativity and with separate space and time, it will behave classicly, not form black holes or approach asymptotes. You would not get pair-production and annialation as a required outcome of symmetries, either. What *stuff* exists won't naturally have decay pathways since that happens because of vacuum pair production or annihilation. It won't have quantum *spin*, since that (one of the triumphs of physics) appears naturally in the equations of motion due to spacetime being one thing. That's what makes matter act like solid stuff. Why is a brick solid and not able to pass through other bricks? Not from any rules introduced for the purpose (lawlessness!) but as an inevitable **consequence** of a cascade of emergent properties as you work out the details of having no "special" rules. Everything about that universe needs to be programmed directly, because it's not all snowballed from the most primitive symmetry of spacetime. Good luck getting it all to fit together without contradictions and bugs. --- For more on the main breaking point, check out Feynman's *Messenger Lectures*. It's in book form, and the [live presentation is on youtube](https://www.youtube.com/playlist?list=PL718CB23F9E6478EF)! He talks about different ways to formulate the same rule, and the 3rd way introduces "least action". That turns out to be the keys to the kingdom. Not having conservation on energy implies that the "action princple" is not a way to formulate the laws in your proposed universe. [Answer] You want to read about Emmy Noether, and [Noether's Law](https://en.wikipedia.org/wiki/Noether's_theorem). What this law states is that for each symmetry, there is a conserved quantity. For example, if a system is symmetric regarding rotations about a point, then the angular momentum about that point must be constant, and must be preserved in all interactions. The symmetry relevant here is symmetry regarding translations in space. If there is nothing inherently special about one location in space versus another, then momentum *must* be conserved. This is a mathematical phenomenon, not an empirical observation. So, in short, no, such a universe cannot exist. The accelerating objects would fail to conserve momentum. It would be mathematically impossible to write down consistent equations of motion for objects in such a universe. [Answer] Everything would reach the speed of light, simultaneously growing to infinite mass, and therefore infinite gravity, causing all matter to collapse into a single ginormous black hole. (The force of gravity would overtake the new acceleration you propose.) ]
[Question] [ In my story, humanity engages in World War III, ultimately bringing about their extinction. The irradiation of the ocean causes a mutation in an octopus (Enteroctopus Dofleini), enabling her to pass on knowledge to her offspring. Over the course of thousands of years, the octopus gradually becomes the dominant species on the planet. Technologically they flourish. Starting with stone tools, their civilization progresses past modern-day human science. At the end of six thousand years, they create huge Generation Ships, take the species off the Earth, and disperse across the universe. While designing their history on Earth, I noticed a cultural hole--the lack of art. Now, these octopuses have a narrow emotional spectrum--curiosity, fear, admiration and disgust. However, the need for stimulation, something to occupy themselves with, as well as the desire to capture scenes from their history, is to me sufficient basis for the development of artforms. Literature, music, and sculpting I have covered. However, I'm having difficulty when it comes to painting, specifically the materials required to produce it. Assuming everything remains aquatic (the act of painting upon a surface, the materials that make up the paint, etc.), **how can an octopus create the materials needed for painting underwater?** * Octopuses will eventually venture onto land to gather materials, so assume for this question that this has not happened yet. * Assume that this is occurring fairly early on in their history. Their technology is still pretty simplistic. [Answer] **Frame Challenge - Not because there's anything wrong with the question, but I think there's an interesting answer** The Octupi specifically don't do permanent Art as it conflicts with their culture, which believes that Permanence is to be avoided and that it was a key cause of the downfall of Humanity. As Ocean dwelling creatures - their entire culture is built on the understanding that everything changes - the Tides change, the winds change, The Ocean changes **Even the Octopi itself, it's colours, changes** - Nothing is ever as it once was. Then, couple that with when they started to explore the remains of Human civilization - they believe that Humanities attachment to 'trying to keep things as they are' was a fundamental reason for their downfall and subsequent annihilation. And so when they create Art, they do so knowing that the Ink underwater will never dry and that tomorrow it might be washed away or swirled into something anew. [Answer] Octopuses do not paint as humans do. Instead they arrange colored pebbles or (where the water is very still) sand. Octopus art is meant to be observed at a distance. It is possible that they may be able to dye things in their ventures on land and bring them underwater for this purpose. Alternatively, they could favor sculpture instead. Possibly even tactile sculpture, which is not unknown among humans, but has distinct advantages for a species often lacking in light. [Answer] There are lots of things under the sea that both (1) have and maintain color and (2) can be made into a fine powder or fluid. So, assuming "fairly early on in their history" is at least equivalent to human cavemen and "Their technology is still pretty simplistic." includes being able to turn things into powders, then this is no problem. There are also various viscous fluids in oceanic nature that can act as a medium for painting under water (mucus and oils from various animals, then eventually petrochemicals just like on land). So, "mixing colored powdered into egg whites" on land becomes "mixing colored powders into whatever slime hold clumps of fish eggs together" ... this is also an easy analogous activity. There are plenty of hair-like things from sea plants and animals that would make for good brushes...especially if they are kept wet (even if they would get too stiff when they dry out). But the earliest paintings were done with hands...and octopi have those in abundance. So, **smearing colored mucus onto a rock with tentacles** would be their equivalent to cave paintings. The painting techniques could progress analogously to humans' with their technology level if you want them to. I mean, I assume they eventually make something akin to paper and/or canvas from seaweed or animal skins or whatever. A bigger challenge is thinking about what are they using for light (instead of fire). One option is only painting near the surface, but more likely your octopi civilization is harnessing some kind of bio-luminescence, right? Until they figure out the advanced technology, the naturally occurring stuff is usually blue-green (I think), so that's going to have a huge effect on the perceptions of colors. Fire has a similar problem (being strongly orange-red) and many surviving cave paintings are in caves deep enough that no sunlight will reach them; so, again, this is not a problem for the earliest paintings which will just be like single color stick figures anyway. But between the primitive and advanced (electric light) stages, there is going to be a big difference is natural light availability and quality. Mosaics using colored rocks and shells and stuff (instead of ceramic tiles) would also be a natural low-tech visual art-form under the sea. [Answer] Some pigments used by ancient civilizations came from aquatic creatures. The best example is [Tyrian purple](https://en.wikipedia.org/wiki/Tyrian_purple), which you obtain by butchering sea snails. So octopi can get purple from snails, and black from their own a... I mean, syphon organ. The blood of some crabs is blue and many other creatures have red blood. You might be able to get some yellow from corals, and algae can be used for green. In time the octopi would figure these out just the same way humans did, through the FAFO method (Frolick Around and Find Out). [Answer] Oil on canvas is pretty much a viable approach underwater, once these creatures develop the necessary technologies. Variations like oil on stone are even easier. The key is extracting oil from the sea fauna, something a sapient creatures will have early on. The pigments extractable with oil will be quick to get discovered. And I think that you miss an important art form for an octopus - the dance. [Answer] ### With coloured or textured sand and other raw materials Various aquatic creatures cover themselves with debris. [Caddis fly larvae](https://en.wikipedia.org/wiki/Caddisfly) for example will cover themselves with sand, soil and gravel. Gerald Durrell recounted in one of his books that as a kid he caught some caddis fly larvae, scrubbed them clean, and put them in tanks with different coloured sand to get red, white and blue striped larvae. He did say the stripes weren't that even, but then the achievement was getting them to do it at all. Many sea creatures have sticky secretions which set underwater, so there's no problem with raw materials. The octopi may not produce it themselves, but then we don't produce paint from our bodies either. Their artwork could be more like mosaics, at least initially. But it doesn't take much technology to grind vegetable matter finer, or locate fine sand. ]
[Question] [ My blind, intelligent species has advanced technologically to the stage of space exploration through the usage of FTL travel. The reason for their blindness is evolving underground, after the surface had been rendered uninhabitable by a GRB. The environment they were in was one of massive cave systems, which had an ecosystem capable of supporting life. Because of this, this species relies on hearing for their primary sense, using highly sensitive "hairy" antenne on their heads to pick up sound, as well as using echolocation. They have one primary pair of arms located on their bodies, and a secondary pair of arms on their backs, which they use for emotion and cleaning their antennae and proboscis mouths. This species also has 4 legs, and an exoskeleton. These secondary limbs are highly mobile, but smaller/weaker than the primary limbs, but still able to be used for manipulation of objects, with 3 fingers on each hand. I want to give them a unique firearm, different from humans, but I am having trouble imagining what that would look like. In combat, what would their equivalent of sights be? How could a firearm make use of the secondary limbs (which can reach across to their front). I am thinking of something similar to the bren gun, where the magazine is located at the top to make reloading easier. [Answer] [Frame Challenge] They probably wouldn't. As @Questor hinted at in a comment, if this species has hearing as their primary sense, they'd be reluctant to use explosives as a propellant for the same reason you would be reluctant to use a flashbang in a fistfight. In media res, a Star Wars-esque laser gun would make sense, but that begs the question of how they got there: If a laser gun is just a cool future space version of an AK-47, what would your species' AK-47 be? I propose: Crossbows. Your species could theoretically load a crossbow faster a human could (strong arms pulling back the string at the same time the weak arms are loading in a bolt) and tension-propelled missiles are a lot quieter than explosively-propelled ones. As for "sights", maybe the primitive version was just a sound funnel that helped narrow down the aiming, but more modern versions have assistive technology outside the species' normal range of senses. In Andy Weir's Hail Mary this is touched on (though I won't spoil the details as the book is a JOY to read). If they made it to FTL then they know light exists, so they might have literal sights on their weapons that communicate relevant visual information in a medium they can understand. [Answer] ## High Energy Lasers with PSLs One of the biggest hinderances in the military adoption of laser weapons is not about power, but about them being so bright that they burn soldier's (and nearby civilian) retinas to see the pulse of plasma generated where you strike; so, even in a future tech setting, there is a lot of reason for humans to continue to use kinetic firearms and not HELs. However, our biggest reason NOT to use HELs is a non-issue for your aliens. They are blind; so, the bright flashes of light not only don't effect them, but they also create a secondary advantage against seeing enemies. Our loud percussive weapons will destroy thier hearing and deafen them, and thier bright HELs will destroy our retinas blinding us... this alone should be enough to make these weapons feel pretty alien to one another, but we can take it further... [![enter image description here](https://i.stack.imgur.com/qmyf9.png)](https://i.stack.imgur.com/qmyf9.png) [Answer] # Aim by Sound There is a pretty simple way to aim horizontally by sound. Put a camera on the gun with some sort of target recognition and detection. If the target is to the left, the sound is louder in the left ear. If the target is to the right, the sound is louder in the right ear. This is very similar to the approach used in experiments where neurons are grown in a vat and trained to play video games like Doom and they can aim very quickly using this sort of input. Humans can also learn to aim very quickly by using this approach. Vertical aim is harder, but can be done through pitch. Make the noise in the ears consist of two tones - a low tone and a high tone. If you are aiming exactly at the target, the tones become the same frequency and sound perfectly harmonic. If you are aiming below or above the target, their frequencies drift apart proportionally to how off mark you are. The low tone is louder than the high tone if you're aiming below the target and vice versa. If their hearing is very sensitive, they could achieve high accuracy and precision on both axes. Overall this would allow them to aim almost as quickly as sighted people, limited primarily by the target recognition ability of their camera. As for the loud noise of the gunshot, whichever hearing device provides them with the aiming tones could also block out the noise of the gunshot. [Answer] I would like to argue a bit against Samuel Page's point. While our current firearms are nice and refined, they haven't always been like that. The [fire lance](https://en.wikipedia.org/wiki/Fire_lance) was pretty much the medieval version of bringing a flashbang to a gunfight. Most of the firearms <1800 or so were seriously uncomfortable or even dangerous to the user, and that's the reason why they were mostly used by the unskilled, expendable drafted parts of the army. In 1450 or 1500, a highly skilled sniper would be using a longbow or maybe some form of crossbow, not an [arquebus](https://en.wikipedia.org/wiki/Arquebus). The arquebus was used by the random peasant that was drafted shortly before engagement. They were handed a mass-produced crappy arquebus that required maybe an hour of training, then pointed vaguely in the right direction and then hundreds of them fired volley after volley towards a similar line of enemies. No need to learn to aim, the bullet won't fly where you aimed anyway. This level of firearm would work equally "well" for a blind species. To help aiming, maybe draw a line in the dirt that you can feel with your feet, so that you vaguely aim in the right direction and that's it. Yes, your soldiers will walk home with debilitating hearing damage, but who cares? Now on to more modern weapons. Probably for a hunter, a hobby shooter or a sniper, firearms would still not be the preferred type of ranged weapon, due to the potential hearing damage. But since these use cases rarely need quick reloading, so something like a longbow or crossbow might be more effective, especially if you factor in "magical" scifi materials. Regarding targeting aids: The easiest one would probably be a directional microphone, since they would feel "natural" to a hearing-based being, similar to how optical magnification feels "natural" to us. But if you have more tech available, you can use any kind of target-detecting sensor (heat/infrared sensor, optical sensors) and translate their targeting information into auditory signals. Btw, it would help a lot if these beings had more than two ears. With two ears you cannot ever accurately pinpoint a 3D location of a target. Two ears mostly give you a "ring" of possible target locations, which is the reason why two-eared animals with good hearing have to tilt their head sideways to know where a sound is coming from. 3-4 ears would make that pinpointing possible without tilting the head. [Answer] It would be best for them if the weapon had some kind of smart surface. In this diagram the weapon would have a needle pointing at the target they could feel. [![enter image description here](https://i.stack.imgur.com/LqLYJ.png)](https://i.stack.imgur.com/LqLYJ.png) I don't have a 3d program handy so substitute different heights for different colors. [![enter image description here](https://i.stack.imgur.com/yf4dW.png)](https://i.stack.imgur.com/yf4dW.png) Think of this a braille for weapons. Real blind people use braille to read books. [![enter image description here](https://i.stack.imgur.com/HC4qk.png)](https://i.stack.imgur.com/HC4qk.png) This would be a more advanced version. Perhaps sounds could be used to augment this touch sensitive surface. Additionally if their brains could handle the conversion rate audio sounds could be turned into binary communications. Beep-boop-beep-boop-boop-beep 101001 Now of course your not limited to just beep and boop if you don't want to be you could buzz,hmm,whirring noise, or etc. The sounds don't even have to be audible to other lifeforms just themselves. The downside is they would have to recognize these words fast, but a species that is dedicated to sound should be exceptional at this as humans who lose there sight are often exceptional at recognizing sounds and echo location. Also bats. Primative computer modems used audio signals over phone lines to communicate at 300,600, and even 1200 baud. 57,600 baud modems existed but I suspect the audio tones would be too complex for them to decode in real time. They could probably manage the slower baud rates. Morse code is could be viable at fast enough speeds. Maybe the weapon actually said the enemy is at 47.28 degrees relative to the alien. [Answer] Since they rely heavily on sound, the sights could be replaced with some kind of audio system. Small microphones on the barrel could pick up subtle echoes and feed directional audio cues to the shooter via headphones. The intensity and direction of the sounds could help aim the gun. For reloading, the secondary smaller arms could come in handy. The gun could be designed with two separate parts - the barrel/firing mechanism and the ammunition magazine/stock. The smaller secondary arms could detach and reload ammo magazines while the primary arms keep the barrel aimed and ready to fire. The magazine could use a top loading design as you suggested. The secondary arms could reach over the top to detach and replace magazines rapidly from a pouch or bandolier. Instead of a typical stock, the gun could have dual handles or grips on either side. The primary arms could hold the barrel while the secondary arms detach and reload magazines from the top. To utilize echolocation, the barrel could contain emitters that send out pulses. The echoes would create a soundscape for aiming. The gun could even link up wirelessly to implants in their sound-sensing antennae. [Answer] The question answers itself. Since you define that the "aliens" can for all functional purposes "see" using sound, then there is no reason to believe they wouldn't use missile weapons, including loud firearms. It may be painful or "blinding" to use such a loud weapon, but then it becomes a risk vs reward question. Chances are the prime directive of all life "to survive and make more" will override or adapt to any suffering. ]
[Question] [ I'm using an alternate version of the Milky Way as my setting. I need to know how far it is from one planet/area to another, and know how long it takes to jump via hyperspace -- Yes, I realize hyperspace is hand-waving. I still need some rules to tell a story. :) In my world, jumping via hyperspace looks like this: * You jump from one gravity well to another (anchors) * Ship does a chemical burn to escape the origin well influence, makes calculations and then jumps. * Hyperspace/jump time is of course less than "realtime" due to time dilation (like to have a way to figure out that based on distance) * Ship emerges outside the target gravity well and decelerates. I'd love to have a working map similar to this [star wars map](https://www.dropbox.com/s/94w2q6kkzgrc9kz/sw.jpg?dl=0). Looking at that map, I'd know how long it would take to jump star to star from the Core Worlds to the Inner Rim. Below was where I started, found the grid over the galaxy with the light year distances. I looked at galactic coordinates, but found it confusing and probably not necessary for the readers (or myself). Again here, just need a way to figure out basic stuff - how long does it take a ship to jump from Sagittarius to Orion, for example. What's the distance, and how long in hyperspace vs. realtime. It doesn't really matter how "real" it is, as long as it's consistent. I'm just stuck trying to work it out. [![Base map](https://i.stack.imgur.com/jQyYu.jpg)](https://i.stack.imgur.com/jQyYu.jpg) [Answer] ## Light-years per hour What's to stop you from using real-space distances themselves by, say, multiplying by a common scale factor? For example, hyperspace speeds might be measured in units of real-space ly/hr. A ship at Earth with a "top speed" of 200 ly/hr would take ~125 hours or ~5 days to reach Sagittarius a\* (galactic center) 25,000 ly away, for example. It's perfectly consistent and the units make intuitive sense to the reader. --- If you desire different travel times measured from different observers, say, one observer in real-space and another in hyperspace, a common scale factor that describes the "rate of time" of hyperspace can be added while keeping things simple. Travelers would likely use the "real-space velocity" that outsiders observe, to show up on-time for deliveries and such. If, by their clocks, it takes 20 hours to travel 1,000 ly, then their speed will be, by their perspective, 50 ly/hr. However, if an outsider in real-space observes that 40 hours elapses from trip start to end, then they will measure the travelers' speed as 25 ly/hr (and so, the ship's top speed may instead by listed as "25 ly/hr"). The scale factor in this instance is $\frac{1}{2}$, which describes how much *slower* (or possibly *faster*) the travelers are from the outsider's perspective. In all cases of different top-speeds & distances, a common scale factor of $$\frac{\text{traveler-measured time}}{\text{outsider-measured time}}$$ can be multiplied to the travelers' top-speed to find their outside "real-space" velocity. --- This math is done behind the scenes by you. What you would relay to the reader is the result of your artistic decision, the scale factor itself (hopefully a nice, round number). Ex.: "Ships age 10x slower in hyperspace than real-space" (a 20 hour trip at 50 ly/hr for the travelers is a 200 hour trip at 5 ly/hr for an outsider). [Answer] **This is something of a [Frame Challenge](https://worldbuilding.meta.stackexchange.com/q/7097/40609)** And something not of a frame challenge. I think the reason you're stuck is because you're *married to your map.* You see, sometimes we get way too caught up in the desire to be "realistic." I know you didn't specifically say that, but you're hanging on to a realistic map of the Galaxy. Good worldbuilding is knowing when to hold out for "realism" and when to let go and let imagination take over — especially when it's one of the small things, like travel time. Since humanity knows absolutely squat about FTL travel, you're free to *declare* what your travel times will be. This is really, really important! Because when you start thinking about interstellar travel you need to realize... * The gravity well representing your planet is moving. * So is the gravity wells for any moons orbiting your planet. * The gravity wells of other planets are moving. * The gravity well(s) of your star(s) is/are moving (eeek!). * The gravity wells of each galactic arm are moving. * The gravity well (which isn't uniform) of the galaxy is moving. * And finally, the gravity well represented by the center of the galaxy is *non-trivial.* *And that list is an awful simplification that makes angels weep and demons laugh.1.* But the point I'm making is, you're flying from one moving target to another moving target through a medium that is, itself, moving. Worrying about how to calculate time of travel is, when you start staring the specifics in the face, pretty much a waste of time. (Every possible pun intended!) **What should you do?** * **Resource:** [Massive Impact Design in the World's Subway Maps](https://99designs.com/blog/creative-inspiration/the-worlds-subway-maps/) (image below courtesy this link and you really should read this article, the very last image is great.) [![enter image description here](https://i.stack.imgur.com/wJ7c6.png)](https://i.stack.imgur.com/wJ7c6.png) In the basic need, the complexity of subway travel is very little different from the complexity of interstellar travel. Humanity has wavered back and forth between geographically-related maps (the subway map of lower Manhattan on the right, above) and *abstract but much simpler to understand maps* (the subway map of lower Manhattan on the left, above) since the beginning of Subways. Some people care about their geographical location. *Most people don't.2* What they really care about is getting from where they are to where they're going as quickly and as easily as possible. Because the details of travel are far below their radar when it comes to the important things in life — like where to get the latte you're desperate for. Think about it. Whether you think of the days before flight, the days before rail travel, or the days before sea travel, all most people wanted to know was "how long will I be on this contraption?" Otherwise, the simpler the map, the simpler the process of levering the money for the ticket out of their wallets. Therefore... **Calculation of time traveled is a function of [Narrative Necessity](https://worldbuilding.meta.stackexchange.com/q/7281/40609)** In other words, how fast do you want to get from Sol to Rigel? Pick a number. It's relevance to reality is irrelevant. Its relevance to your story, is relevant. If you need people to get from Sol to Rigel in a week, there's your number. You now know the distance between two points and the time you need to get between them. Distance divided by time equals velocity. You're done. Your shipboard computers will be doing all the heavy lifting anyway, right? Your readers don't really need (and many times, don't really want) to know how you calculated the transit times. They don't even particularly care if they're consistent. This is because travel times (unless a critical part of the plot of the story) are really just window dressing. Now build an abstract map of the galaxy that shows major transit/trade paths very similar to what you see with subways, mark the time between the various "stops," then pop a cream soda and enjoy looking at a map that *every reader of your story will easily understand and appreciate.* And remember that, from the perspective of characters in your story, most people will step up to a computer and say, "I want a one-way ticket from Wolf 357 to Coruscant." Plug in credit card, get robbed by everyone from tourist agents to insurance brokers to the Teamster's union, and out comes the proverbial piece of paper that says: > > BOARDING TICKET XH9S779WKLZFL3260SJ1 departing Wolf 357 from orbital station A-227 on February 5, 2957 and Arriving Coruscant via orbital station V-002 on March 14, 2957. Experienced travel time: 13 days. Elapsed travel time: 37 days. PADDS enhanced with the CROSSTIME protocol will automatically update to local time and adjust your medical records to reflect your experienced age. All others must visit the courtesy desk for assistance. Have a nice trip and thank you for flying with Fontain Aerospace Routine Travel! > > > A computer labeled "Magic Happens Here" did all the work and unless you really think you readers will be impressed, no one needs to know how sausage is made.3 --- 1 *I get the idea that gravity falls off very quickly, but someone would need to prove that a small speed bump not noticed at sublight wouldn't ruin your suspension at FTL speeds.* 2 *That's somewhat of an unfair simplification. People care about their geographic location. Or, more precisely, their cartographic location. What they don't care about is the time required to figure out what the geography is between where they are and where they're going. The reason abstract maps are popular (whether or not they're more popular depends on a lot of variables) is because they simplify the process of choosing a destination. They're easy to read and don't look confusing. However, the purpose of this post is not to enter the "which is better?" debate. I'm just suggesting that if you step away from a "geologically accurate" map and start looking at this from the perspective of "how do people want to figure out where they're going?" most of your problem is, IMO, solved.* 3 *And a good thing, too, because figuring out the distance between any two arbitrary stars is no small thing. If you really want to get lost down that rabbit hole, head over to [The Astronomy Nexus](https://www.astronexus.com/hyg), download their database, and start working through how to convert Earth-to-Everything measurements to SomethingElse-to-SomethingElse. I suspect you'll quickly discover it's more work than it's worth. Although if someone wanted to earn the gratitude of every worldbuilder on Earth, building a free online interface that returned the distance between any two arbitrary stars would probably do it. If that already exists, for the love of [Glarnak,](https://worldbuilding.meta.stackexchange.com/a/3789/40609) update the [worldbuilding resources](https://worldbuilding.stackexchange.com/q/143606/40609) page with it.* [Answer] The original *Traveller* role playing game had limited jump distance (most advanced drives could reach six parsecs) and all jumps took the same time -- a week (as I recall, it was a few minutes more or less than 168 hours, but call it a week). They had fusion drives, and antigravity, of course, but same basic thing -- space had to be flat enough to allow a jump. This isn't a "speed" as such -- a jump of 6 parsecs took the same time as one of one parsec. In the end, you're handwaving the drive anyway -- you can handwave any speed or pseudospeed or jump time you like to make your world work the way you want it to. [Answer] # Draw a Picture [![enter image description here](https://i.stack.imgur.com/mzOgy.jpg)](https://i.stack.imgur.com/mzOgy.jpg) Put a picture of the galactic disk in the book. Draw circles for the worlds where the action takes place. To see how long it takes to get from Earth II to the Ugly Baby Nebula just measure the distance on the map. Use a ruler for a paper map. For a digital map use the measuring tool. For GIMP it is the compass-looking one. [![enter image description here](https://i.stack.imgur.com/74Qh5.png)](https://i.stack.imgur.com/74Qh5.png) Compare the distance to the red segment. The red segment is 5,000 Light years long. Once you have the distance, just divide by the speed of the spaceship, to see how long it takes to get there In this example the distance is about 8 red segments or 40,000 light years. If the ship goes 300 light years per hour then it takes about 133 hours or five and a half days to get from Earth II to the Ugly Baby Nebula. [Answer] **To the observer, jump time is random.** > > Ship does a chemical burn to escape the origin well influence, **makes > calculations** and then jumps. > > > A fine discussion of these calculations here [How long can it really take to calculate a hyperspace jump?](https://worldbuilding.stackexchange.com/questions/206192/how-long-can-it-really-take-to-calculate-a-hyperspace-jump) Jump time varies. A lot. It is not a straight line though sometimes it can be. At worst it is a circuitous route through higher dimensions. It can be the straight line one time and the circuitous route a minute later, for the same jump. There are a lot of things going on in multidimensional space. The time for a jump follows a normal distribution and is unrelated to origin and destination. Most jumps take several hours. Some jumps take no time, or very occasionally less than no time. Some jumps take a long time. Very occasionally it is a very, very long time. [Answer] # jump time is based on energy needed to transit systems In our universe energy is neither created nor destroyed. It should be the same in fiction. I'm thinking * Once a ship enters hyperspace the ship part of the ship (ship minus exhaust matter) must gain enough kinetic energy so that it would have gained or lost enough energy to get where it's going. That is, if we only where considering 1 star of mass $M$ to get from $R\_1$ to $R\_2$ with a would require a burn of $$\frac{M G}{R\_2} - \frac{M G}{R\_1} = \frac{1}{2} \Delta V^2$$ * The space ship can only travel along the direction of it's center of mass (minus the burned fuel) in hyperspace. This direction is the direction that light would have taken if nothing moved. Gravitational lensing on hyperspace travel can be a major issue if near a massive object. * The fuel expended during hyperspace travel also exits somewhere extremely random when the space ship does. * The velocity when exiting hyperspace is based on wherever we started from. * Due to how the hyperspace shield opens we want to ensure that the differences in acceleration between different parts of the space ship are tiny to prevent some sort of catastrophic failure. Hence needing to be far from any center of mass. This goes as $\displaystyle \frac{1}{r^3}$ * If we were to gain energy going to $R\_2$ we would counter intuitively need to thrust in the opposite direction of where we wanted to go while in hyperspace. **To specifically answer the question:** * A hyperspace jump is just based on how long it takes to thrust in hyperspace to achieve the appropriate delta V that corresponds to the energy it takes to traverse the distance. This means hyperspace travel is very fast when traversing equipotent surfaces. ]
[Question] [ I am doing worldbuilding on a region centered around a gigantic lake in the sub-tropical region in the northern hemisphere of a planet. I want the lake to incredibly huge, like around 2 million square kms. My question is, would it make sense for this lake to be freshwater at all? If no, would this now saltwater lake need to be connected to the sea/ocean and can it be underground? I tried searching for any answers, but I was not able to find any answer to if it is possible for it to be freshwater at all. The idea for the biomes would be wetlands next to the lake itself, followed by jungles which turn in shrubland and then into a sort of savannah followed by a desert as we go further away (I am talking about a 5000 kms \* 6000 kms sort of area). Would this make sense at all? I hope someone can help me with this dilemma! Thanks to all who take time to read this. Cheers! :) [Answer] The larger the lake the harder it is to generate the required conditions for it to be fresh water. You are asking for a lake area similar to the size of the mediterranean sea. This is not impossible, it's just improbable that the oceans, mountains and uplands are arranged in such a way that it can exist. It would also require a vast drainage area to keep it topped up. The mediterranean sea was itself cut off from the Atlantic a few million years ago and was reduced to a few hyper-saline lakes which were then flooded to produce larger brackish lakes until the Atlantic Ocean finally broke through. So a second issue is getting sufficient rain into the lake to keep evaporation at bay. In summary it's possible but unlikely. The bigger the lake and the hotter the climate the less likely it is. [Answer] # Salt Dynamics: Salt builds up over time in bodies of water that don't drain out anywhere else. Lakes always have new fresh water draining into them bringing tiny amounts of salts with them. A lake with an outlet loses salt through the outlet and that water is replaced by fresh. A lake with no outlet gradually accumulates salt as the fresh water evaporates, leaving any salt behind. So for a large body of water to be fresh, it needs to drain into a lower body of salt water. Very small lakes can be transient enough for this not to matter. But a BIG body of water has a lot of mass and volume behind it. The flows needed to outflow that much fresh water will rapidly cut rock and soil alike. While it is possible to have such a large body of fresh water, it is unlikely and probably fairly short-lived. [The Great lakes](https://en.wikipedia.org/wiki/Great_Lakes), for example, formed due to glaciation damming up the water, pushing down the land, and providing a huge influx of fresh water to form the lakes. They are gradually disappearing as the depressed land from the glaciers gradually rises and Niagara falls slowly cuts it's way back further and further. [![enter image description here](https://i.stack.imgur.com/jskgA.png)](https://i.stack.imgur.com/jskgA.png) [![enter image description here](https://i.stack.imgur.com/nlvWj.png)](https://i.stack.imgur.com/nlvWj.png) [Answer] I got your giant lake right here! [![lake agassiz](https://i.stack.imgur.com/6napw.jpg)](https://i.stack.imgur.com/6napw.jpg) > > Lake Agassiz was an immense lake that existed in north-central North > America during the last ice age. It is named for Louis Agassiz, the > first scientist to realize it had been created by glaciers acting as > dams. Larger than many modern seas, its waters were fresh, not salt. > At its greatest extent it covered an area larger than California (see > map right) and held more water than is today contained in all the > freshwater lakes of the world combined. > > > <http://www.macroevolution.net/lake-agassiz.html> 140,000 square kilometers is smaller than the Mediterranean sized lake you want. But you could make your lake the same way our world made Lake Agassiz - lots of glaciers, melting. During the ice age your world had more glaciers than ours and when they melted, your worlds geography let the water accumulate in your vast lake. ]
[Question] [ This world is an alternate Earth similar size, mass and distance from its star to our Earth. The atmosphere is similar in composition to Earth except at 5000m altitude the pressure is two bar and the temperature is typically 20-30 degrees C. Humans live on a very large high plateau 5000m above the swamps and shallow seas below **(sea level at 50 degrees C and 90%+ humidity)**. Snow is known but is seen only very occasionally on the very highest peaks. They do not usually descend very far into the very hot and humid lower areas, but have decided that an expedition should be mounted to explore these areas. What measures and mechanisms can they take to combat the heat and humidity and extend the area they can explore? Most areas are covered in dense tropical rain forest on rough downward slopes. The temperature and humidity increase with the distance descended. Their technology is limited by an extreme lack of metals, so no electrical apparatus and no significant\* metal artifacts, but they can use anything else that could be made without electric power or significant\* amounts of metal. \*Roughly a kilo of metal can be spared for the expedition if required. 10kg of metal would be considered a vast expense. Additional context I was planning to use the Canadian Humidex as a guide for human survival limits my crude estimates for how long a person might survive being : Orange zone days to weeks, red zone hours to days and above that minutes only <https://www.canada.ca/en/environment-climate-change/services/seasonal-weather-hazards/warm-season-weather-hazards.html#toc7> **Update** Perhaps I was not clear enough. The issues to be overcome are mainly high temperature and high humidity. The humans have little metal so no industrialization as we know it, but they have had the enlightenment they can experiment and invent things so there's lot of other scope - sealed suits using rubberised cloth, cooling by letting alcohol in a backpack boil (or even diethyl ether) bellows to modistly compress humid air below its dew point and then expand, quick lime to absorb moisture etc etc chemistry is your friend here. [Answer] **Stay high.** [![balloon over forest](https://i.stack.imgur.com/4uVB3.jpg)](https://i.stack.imgur.com/4uVB3.jpg) [source](https://www.theadvocate.com/acadiana/entertainment_life/festivals/article_feb02d9c-cb5c-11e9-8f73-178bdfc136a9.html) Your people make hydrogen balloons and use wicker baskets, like the explorers in Jules Verne's [Five Weeks in a Balloon](https://en.wikipedia.org/wiki/Five_Weeks_in_a_Balloon). They stay at an altitude comfortable for them. Really they are interested in other lands that are of an altitude comparable to their own and if they find such that is where they will land. Lowlands will be safely surveyed from above. This voyage would be preceded by long study of wind pattern on their plateau such that explorers can leave on the wind and expect to return. [Answer] # Dazed and confused : I'm sorry to say your humans are not in a great position. Most of the assumptions in other answers assume the people are different from normal humans - better evolved for the temperature and pressure. I'm not making those assumptions. I'm going with what we know of actual humans. If these people are different, we have no frame of reference to give a science-based answer. They do have one advantage. They have (assumedly) become well-adapted to the increased relative oxygen of your planet, and the effects of increased pressure in general. This might improve their tolerance as a result of pressure. With all that humidity, there isn't likely to be a lot of direct sunlight due to the oppressive cloud cover. But they are pretty much out of luck. They are already at the edge of oxygen tolerance. The kind of temperatures they would experience at those levels of humidity will kill them quickly. # [Pressure](https://derangedphysiology.com/main/cicm-primary-exam/required-reading/respiratory-system/Chapter%20923/physiological-effects-high-and-low-barometric-pressure): Nitrogen narcosis doesn't have full effect until around 15 bars, but at three bars (which your people will experience quite quickly) there are at least some neurological symptoms and impairments. Prolonged exposure to [excess oxygen](https://en.wikipedia.org/wiki/Oxygen_toxicity) starts to have toxic effects at 1.6 bars. at this level, the partial pressure of oxygen is about 8 times that at standard temperature and pressure. We'll assume your people can tolerate at least this level of toxicity, since their society is already at this level. But they may be suffering some neurological issues as a group, including a tendency towards seizures and vision problems (especially myopia). Most of the research on oxygen toxicity is looking at people who are either exposed to high levels of oxygen for brief periods, or who adjust the partial pressure to physiological levels in a gas mix. These won't be options for your people. They will have serious neurological complications, including serious seizures. Prolonged exposure will cause hypertension and [acute lung injury](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2823143/), which ironically will cause lack of oxygen and resulting organ damage. You might be able to rig up something that causes your people to rebreathe air, effectively reducing O2 concentration, but then you start to face CO2 toxicity. It's tricky to parse out how much of CO2 toxicity is due to low oxygen, but at sufficient pressures, it won't matter. The CO2 will out-compete O2 in the blood, and I'm guessing your people will be acutely vulnerable to hypoxia (being so adapted to high oxygen). # Temperature & Humidity: A lot of scientific research has relied on assumptions about the body and it's ability to tolerate prolonged heat. But with climate change, studies are being done to validate these assumptions. The old results say people can't sustain anything higher than about 46C at 50% humidity - well below your 50C and 90% humidity. The [new results](https://newhampshirebulletin.com/2022/07/15/how-hot-is-too-hot-for-the-human-body/) are less favorable and frankly a bit grim. Your body sweats in response to heat. But this only works if the sweat can evaporate. At the temperatures & humidity you're talking about, sweat will simply drip out of people and do nothing to cool them. At the temperatures you are discussing, humidity would need to be less than 10% for sustained endurance. [![enter image description here](https://i.stack.imgur.com/FTyhA.png)](https://i.stack.imgur.com/FTyhA.png) But wait, it's worse. At increased pressures, [water evaporates](https://education.nationalgeographic.org/resource/process-evaporation) more slowly. So sweating is less effective than it would otherwise be. So your explorers will die of heat stroke, choking on their own fluids, too confused to do anything to help themselves (which would be pretty much nothing but going back home). # Is There Hope? Unless the other conditions on your planet are different than on Earth, then not really. So you need to adjust your planet to help your people. The biggest challenge is temperature. So Your intrepid explorers need to keep cooler. How do you do that without tech? * **Caves**: If your world is riddled with caves, these might provide a retreat from the oppressive heat. Caves will have an overall lower temperature if you are far enough into them. The temperature is likely to be at the [mean-average temperature](https://en.wikipedia.org/wiki/Geothermal_gradient). Around here, with seasonal variations, that can be quite low. This may not be the case on your world. If your planet had previously experienced a prolonged cold period where deep permafrost formed (as happened on our Earth during the Pliocene) the underground temperatures could be considerably cooler than surface temperatures. * **Seasons**: You can adjust the temperature and humidity with seasonal variations. So if there is a wet and dry season, humidity can go down. If there is a warm and cold season, then temperature (and likely humidity) will vary. This might put more of a range on exploration, since they would need to get back to livable temps before the seasons change. * **Rivers**: A cold river coming off of a mountain range will provide a retreat to lower temperatures during the peak of daily heat. In this case, they can explore until the river warms up too much. * **Long nights**: Your daily temperatures may fluctuate greatly. So if, for example, you have a night that lasts for a long time (like several days), the temperatures may drop considerably by the end of the night. If your caves are cool enough, the explorers could retreat to caves in the day and look for their next cave at night. I see lots of great drama as the temperatures climb and the pressure-addled explorers become increasing desperate to find shelter. * **Mountain ranges**: given higher elevations your explorers can retreat to, they could move from mountaintop to mountaintop, braving the heat at the coolest points of the day and season. A network of high-altitude camps and small settlements could let them move from elevation to elevation. # Handwavium: In the realm of possible but not too real, there are solutions to at least some of your issues **Fish Oil**: ...or any other migrating species that arrives on your plateau but lives in the high pressure & temperature zone. Snake oil has a nice ring. Some species produce oils that make a membrane more or less rigid, more or less permeable, and the like. You could justify modest increases in the tolerance for pressure and temperature by saying that the people consume the fats of these species and passively acquire increased tolerance of these environments (in much the same way that fats from cold-water fish remain more soluble in cell membranes, which is why fatty acids from fish improve resistance to heart disease, "hardening of the arteries"). **Drugs**: It is not outside the realm of possible that your people have discovered medicines that reduce the effects of oxygen toxicity or nitrogen narcosis. An anti-seizure drug purified from a plant could prevent seizures, and a drug that lower blood pressure would help counteract hypertension. Drugs that do the opposite to neurological effects counteract these. A drug that dysregulates temperature control SOUNDS like a horrible idea, but something that reduces metabolism while simultaneously preventing sweating (under conditions where sweat isn't cooling you off anyway) might help. A drug that reduces the swelling associated with organ damage to heat stroke might mean your people get overwhelmed by the heat but suffer less long-term damage. [Answer] **Make them Lizardy** [![enter image description here](https://i.stack.imgur.com/8hLuC.jpg)](https://i.stack.imgur.com/8hLuC.jpg) 50 degrees is too hot for normal humans to survive for days on end. But these are not normal humans are they? They have evolved to live at 2 bar pressure on a planet that is even higher pressure at the surface, and is outrageously hot and humid for the most part. It stands to reason these creatures are better adapted for extreme heat and pressure than you or me. Their metabolism works at a wide range of temperatures, like Earth reptiles, and unlike Earthlings whose bodies just stop working if we go up or down by three degrees. I suspect your Lizardarians evolved from something that lived on the 50C surface and only turned into stupid crybabies recently, when their ancestors climbed onto the plateau and got too comfortable. Wah wah, it's too hot down here. Let's go back to the plateau. While they might not LIKE going downhill, they can tough it out with endurance training. Then it just becomes a matter of how much food and water can they bring with them. [Answer] **They walk... there's no difference here between divers in Earth's ocean and your people other than your people can breathe** **Assumption**: Your "humans" evolved on your planet. You don't say that they colonized it and the question doesn't read like they did. Colonizing humans with technology would have brought factory implements that would allow the creation of ceramics, solving the problem entirely. So... you're calling them humans, which really means your evolved species simply looks a lot like us. *What's 2 bars of pressure to a people who evolved to live in 2 bars of pressure?* Answer: nothing. 2 bars to them is 1 bar to us. We evolved in it, we experience it. Doubling that pressure doesn't stop us from breathing it. It just means that coming back down to one bar requires some time. Normalizing everything (divide-by-2) means that the pressure at your planet's "sea level" is relatively about 1.9 bar - which wouldn't stop us from exploring. Given time your people would learn about the bends and build ways to ascend back to the plateau slowly. Otherwise, they simply repel down the proverbial cliff and explore away. They adapt fairly quickly to the higher pressure, although long-term effects can be a problem (but that's not what your question is asking about). **Nope, JBH... They're not colonists and they didn't evolve here...** OK, let's invent the specific condition that your humans are survivors of a calamity. They arrived in escape pods and so might have brought knowledge, but not equipment or significant resources. Let's even assume that space travel is so common that, unlike today where astronauts pretty much all need advanced training and education, they at least understand something like ceramics as the "I'm a new private in the Army" level. Given enough time, they'd figure out how to use ceramics better to handle the pressure.... But back to the point... *The air pressures really aren't that big of a threat.* > > Experienced divers can safely dive to a depth of 40 feet (12.19 metres) when exploring underwater reefs. ... William Trubridge – a 30-year-old New Zealander is the first man to dive 396 feet metres (121 metres) without any assistance. ... The maximum depth reached by anyone in a single breath is 702 feet (213.9 metres) and this record was set in 2007 by Herbert Nitsch. He also holds the record for the deepest dive without oxygen – reaching a depth of 831 feet (253.2 metres) but he sustained a brain injury as he was ascending. ([Source](https://www.kooxdiving.com/en/how-deep-can-a-human-dive-without-scuba-gear/)) > > > But your people *have the ability to breathe...* So, let's use that first number of 40 feet for experienced divers exploring reefs. What's the pressure? Converting PSI to BARs... 3.9 bars. Walking around to explore the environment is well within suspension of disbelief so long as you deal with the effects of [long-term exposure to high pressure oxygen](https://derangedphysiology.com/main/cicm-primary-exam/required-reading/respiratory-system/Chapter%20923/physiological-effects-high-and-low-barometric-pressure). (Link provided as an example, not a full solution.) Yeah... I can't see why any condition of humans can't just climb down to the bottom and explore away. --- **Addendum:** Some comments have been made that I've not given due diligence to temperature and humidity. I could be wrong, but it is my opinion that those comments were made by people who have never experienced high temperatures and high humidity. I have. So has my father. So has anyone living on an island near the equator. My experience was in Houston, TX. 100+ degree weather and 70%+ humidity. It was miserable! But I never felt threatened by heatstroke save once: helping a friend move and forgetting to drink water constantly (dumb, dumb-dumb, dumb!). I lived for years in Dallas, TX and Austin, TX. 100+ degree weather and 50%+ humidity (air conditioning in January...). I never even heard of anyone suffering heatstroke that didn't fail to drink lots of water. Workers worked, joggers exercised, and people played in those conditions regularly. My father's experiences were in the Philippines. 100+ degree weather and 100% humidity for a week on each of several visits. He's still with us at 85 years of age having never suffered heat stroke. And the Philippines natives don't seem to have had trouble with it for who knows how many centuries if not millennia. Folks, heat and humidity need nothing more than three things: time to acclimate, drink lots of water, and rest when you tire. It's not rocket science and the temperature and humidity will not work against the body while it sits in the shade drinking water. *Atmospheric pressure,* on the other hand, can cause problems, especially if experienced for a long period of time. But even that can be overcome with acclimation. So, my assumption remains. Did these people evolve on this planet or not? Because if they did, we're not actually talking about humans from Earth. But even if we were. This isn't a life threatening situation unless people do something drastic — like being forced to run from the saber-toothed Munga beast in the early afternoon. That might cause a few people to be eaten. [Answer] > > Atmospheric pressure, also known as barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa), which is equivalent to 1013.25 millibars,[1](https://en.wikipedia.org/wiki/Atmospheric_pressure) 760 mm Hg, 29.9212 inches Hg, or 14.696 psi.[2](https://en.wikipedia.org/wiki/Humidity#Relationship_between_absolute-,_relative-humidity,_and_temperature) The atm unit is roughly equivalent to the mean sea-level atmospheric pressure on Earth; that is, the Earth's atmospheric pressure at sea level is approximately 1 atm. > > > <https://en.wikipedia.org/wiki/Atmospheric_pressure> If 1013.25 millibars equal 760 mmHg, 1 mmHG equals 1.3332236 millibars. So 1,000 millibars, or 1 bar, equals 750.06173 mmhg. The question states that at 5,000 meters altitude the pressure is 2 bar, which equals 1500.1234 mmHg. Vesper's comment says that if the pressure is 2 bar at 5,000 meters it will be about 3.8 bar at sea level. Slarty's comment suggests the pressure should be about 3.2 bar at sea level. 3.2 bar would be 2,400.1975 mmHg, and 3.8 bar would be 2,850.345 mmHg. So for the atmosphere to breathable at sea level, it would have to have a mixture of gases which are not toxic to humans at their indivdual partial pressures and which add up to about 2,400.1975 mmHg to 2,850.345 mmHg. In *Habitable Planets for Man*, 1964, pages 13 to 19, Stephen H. Dole dicusses the atmospheric requirements for a planet to be habitable for humans. <https://www.rand.org/content/dam/rand/pubs/commercial_books/2007/RAND_CB179-1.pdf> On page 19 Dole writes: > > To summarize, then, the atmosphere of a habitable planet must contain oxygen with an inspired partial pressure of between 60 and 400 millimeters of mercury and carbon dioxide with a partial pressure roughly between 0.05 and 7.0 millimeters of mercury. In addition, the partial pressures of the inert gases must be below certain specified limits and other toxic gases must notbe present in more than trace amounts. Some nitrogen must be present so that nitrogen in combined form can find its way into plants. > > > So a breathable atmosphere must contain betweeen about 60.05 and 407.00 millimeters of mercury (mmHg) of oxygen and carbon dioxide. But a habitable planet will have liquid surface water, and thus it will have varying amounts of water vapor in the atmosphere. Dole discusses the humidity of a breathable atmosphere on pages 19 to 20. Table 4 on page 21 gives no minimum value for water vapor but gives 25 mmHg as the maximum. It also suggests that 10 mmHg might be the minimum pressure of nitrogen. So a breathable atmosphere containing only the four essential gases would have a miniumum pressure of about 70.05 mmHg. Thus an extra 2,330.1475 to 2,780.295 mmHg of non toxic gas pressure would be needed to bring the total atmospheric pressure at sea level up to about 2,400.1975 mmHg to 2,850.345 mmHg while remaining breathable. According to table 3 on page 16 and table 4 on page 21, up to 1,220 mmHg of argon would be breathable, and up to 3,900 (?) mmHg of neon would be breathable. Thus the maximum breathable pressure of argon and neon would total about 5,120 mmHg, 2,269.655 to 2,789.8525 mmHg more than needed. But the combined maximum tolerable leves of argon and neon would probably exceed human tolerance, so a much lower combined pressure would be desireable. It is is good that there over 2,000 mmHg to work with finding the maximum tolerable level. But there would not be much need to mess around with neon and argon levels, since one of the essential gases, nitrogren, is tolerable at high pressures. Up to 2,330 mmHg. So if there is a partial pressure of 2,330 mmHg of nitrogen at sea level, 0.175 to 450.295 mmHg of other gases like neon, argon, etc. would be necessary to bring the sea level atmospheric pressure up to about 2,400.1975 mmHg to 2,850.345 mmHg. Assuming the atmosphere has the maximum amounts of the necessary gases, oxygen, carbon dioxide, and water vapor, that will be 432 mmHg. So to reach the required about 2,400.1975 mmHg to 2,850.345 mmHg, 1,968.1975 to 2,418.345 mmHg of various gases would be needed. Since nitrogen is breathable at partial pressues up to 2,330 mmHg, at most 88.1345 mmHg of neon, argon, xenon, & krypton would be necessary. So if Earth humans colonize the highlands at 5,000 meters altitude, they should be able to survive breathing the air at sea level, if it has the proper mix of gases. But only if the water vapor is low enough at sea level. The question gives the humidity at 90 percent at 5,000 meters and a much lower air pressure, and I don't kow how to translate that to mmHg of water vapor. I note that at 50 degrees C, the specified teperature at 5,000 meters, 90 percent relative humidity would be 74.7 grams per cubic centimeter in one atmosphere pressure. <https://en.wikipedia.org/wiki/Humidity#Relationship_between_absolute-,_relative-humidity,_and_temperature> I guess it might be about 149.4 grams per cubic centimeter in two bar pressure. More research would be necessary to say if the humidity would be tolerable to breathe at 5,000 meters above sea level, or at sea level. Answers to this question contain formulas for calculating the scale heights of atmospheres. <https://astronomy.stackexchange.com/questions/48434/what-are-the-scale-heights-of-the-atmospheres-of-the-solar-system-worlds> And you might want to calculate the scale height of your atmopshere to see how dense it would be at sea level. If the people of your planet are human colonists from Earth, they are likely to be quite unconfmortable living at 5,000 meters with air twice as thick as at sea level on Earth. And thus they will be even more uncomfortable with the ever thicker air as they descend toward sea level. Of course a species of human like people who evolved at the high altitude of 5,000 eters should be quite comfortable breathing the air at that altitude. And when they descend lower to places with denser air, thatdenser air will be closer to what they are used to and and they were be more comfortable with it than Earth humans would be. ]
[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/229996/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/229996/edit) On an alternate Earth I am designing, the entire industrialised world is dominated by a single religion. This religion has many denominations, but in all of them both genetic engineering and advanced AI systems are totally forbidden. This world may sound like one quite self-limiting in terms of its technology, but there is one thing that makes this less the case than it might seem: Whilst it is forbidden to create a machine to fill the role of an organic brain, it is entirely permitted to wire machines with no intelligence of their own to be controlled by an organic brain. As such, whilst their AI technology is limited to around late-2010s level and they refuse to use genetic engineering even for staple food crops, cyborgs are commonplace and replacing body parts (with the exception of the brain) with mechanical ones is virtually completely uncontroversial. Ignoring, for now, the issue of attempting to create better-than-organic mechanical body parts without advanced AI, there is still one potential flaw I can see in this: The kinds of religious groups that would are so hardline against genetic engineering and would regard even late-2010s level AI with extreme suspicion are also generally the kind of people who would be at least wary of casually replacing body parts with artificial ones. In short then, I am asking: Is there actually any way to have a religion which would both prohibit significant advances in machine learning and totally forbid all genetic engineering but which would, nonetheless, be entirely and undividedly happy with the idea of people casually replacing their limbs and organs with brain-controlled artificial versions? [Answer] ## The religion can set constraints, but no cyborg would be halal A religion may set any rules, its narrative serves to make them consistent, not logical. See other answers. This is not a frame challenge: religions are quite often internally inconsistent, so it will be 'realistic' to have such a religion. Also, when the *powers that be* require cyborgs to exist, religions tend to comply and ease up the rules to accommodate the powers that be. **Paradox** When these rules are carved in stone, I doubt if cyborgs would exist at all. Science and religion both embrace cyborgs, but the religion doesn't allow AI or genetic engineering? This will make it very difficult to create a functioning cyborg! Its brain may remain human, but a cyborg cannot be constructed without AI or genetic engineering in its senses, and to connect limbs extensions to the body. When you want to let a cyborg walk, you'll need to connect sensors to neural pathways, which can only be done properly with the help of genetic analysis. Now suppose your cyborg has both legs replaced by mechanics, you'll need to add servos and electronics for balance, which is driven by learning, a system which needs AI to exist inside the Cyborg, but outside its brain. If it is not allowed, you'll end up with a very clumsy cyborg. **Some notes on AI application in brain-machine connections** I view AI as everyday, current technology. I regard learning (or adjustment) on the side of the artificial limb as needed for the cyborgs physics-brain connection. Maybe when the religion would reject "deep learning" or "machine learning" instead of "AI", the discussion in the comments below could have been avoided, but this extra part would not have been written, so thank you @Pelinore and others for the input! In the question, it says *Q: "In short then, I am asking: Is there actually any way to have a religion which would both prohibit significant advances in **machine learning** and totally forbid all genetic engineering but which would, nonetheless, be entirely and undividedly happy with the idea of people casually replacing their limbs and organs with brain-controlled artificial versions?"* When the predominant religion cannot coexist with AI, your people it can't make an advanced, autonomously balancing prosthesis, like this one, <https://daw-usa.com/knee/slk-multi-matrix/> Ok, let's talk medical devices as an example of modern (learning) AI application. In the early 1980s, there were pioneers in NL working on artificial limbs and even artificial hands, connected to the brain. These systems were based on electrodes and patient learning, not machine learning. That is: the patient had to learn to manipulate the device. Back then, these systems were ineffective an unstable. The reason for that: brain signals were multiple, that is the patient had to *invent* how activate multiple electrodes to move the device, all parts of it. When machine learning came in, the number of electrodes could be reduced. The artifical limb would not be "driven" by the brain rather "react" to the brain. As a result, we now have artificial hands, and artificial legs, as well as dancing robots. These artificial limbs "live" for 80% autonomously, behaviour induced by machine learning. By learning, it got used to your brain signals, the level of them.. and the combination connected to certain movements. The patient's learning is still needed, but the device learns too, it adjusts to the patient. Individually.. no system can be copy-pasted from one patient to the other. The ideal in the end, a real cyborg (like in your title) will be able to move his superior limbs intuitively. It will be able to jump and fight, to perfectly connect the motor system in the brain. We're not there yet, but AI, that is machine learning, is regarded as the key to connect the parts while training the patient (or "terminator" or "cybercop", one day) [Answer] Yes. Internal consistency is not a requirement for religious policies. (Citation: Earth.) And while what you've described skirts what we consider inconsistencies (embracing technology in some guises, and rejecting it in others), it's not particularly egregious. One way to overcome a reader's concerns about this is to provide either the justification or the history of how and why the religion adopted these policies, or to hint at them and let the reader fill in the gaps. For an excellent example of this, see the Dune novels and the Butlerian Jihad. Why would a religion reject humans that can take the place of a human mind? History idea: A machine revolt (even something non-violent -- an AI deciding to disable the power grid). Philosophical idea: Only organic minds can go to the afterlife, so making non-organic minds reduces the opportunities for ascendance. Why would a religion reject genetic engineering? History idea: A disease that ravaged a monoculture crop, leading to famine. Philosophical idea: DNA is God's signature, and modifying it is hubris. Why would a religion embrace augmentation and cyborgs? Well, why not? It increases quality of life, and without a reason to reject it (and none of the reasons above apply) it could easily become accepted. I think you're fine here. [Answer] ## Yes What you are describing is not only possible, but practiced by most people. AI are an imitation of God’s life. Many religions consider recreating life to be a sin, since you are saying humans are equal to God. Genetic engineering is modifying God’s life. This is like questioning God’s work. Prosthesis is filling in a gap due to an accident, or is similar to tool use. Full replacement is too extreme for most religions, but if you can remove the prosthesis and the prosthesis is to replace a normal function of the human body people are ok with it. No one cares about people in wheel chairs or with hook hands, so it isn’t as much of a push to get full prosthesis. Genetic engineering either takes a new life like a fetus and modify it without consent, or make a new life and change it fully. Some people aren’t ok with that. AI makes new life in a way that God doesn’t control. Prosthesis on the other hand is just bending metal in a new way and making it work with your body. All but your most restrictive religion allow this a little bit, and many allow it a lot. [Answer] Yes, the answer to your exact question is easy - we have extant religions banning Coca-Cola, shaving, polycotton or eating meat on a Friday except for beaver, so the bar is pretty low. I'm going to try to answer a slightly different question: **what could be a *coherent belief system* that would result in banning AI and GM but not advanced mechanical engineering** ## Begotten, not made Your religion has a supreme Creator who made the Universe and all in it. (She/he/it/they) willed the cosmos and the Earth into being with (thought/song/dream/etc.) alone, exactly as they are now; but when it came to living things, she did not *make* them: she *planted* them, and they grew. The process of developing from a "seed" is sacred. It's what distinguishes the lifeless from the living. The religion's imagery focuses a lot on the wonder of a small, featureless kernel acquiring the complexity and wonder of a fully grown being. This is taken as a sign of "ongoing creation", that the process of development is a live connection between a being and the Creator. In practice, anything with aspects of significant *emergent* complexity is taken as the realm of the divine. AI (and a lot of the more advanced ML) is seen as an attempt to "play God" on an artificial substrate, because the algorithms are designed to "grow" and acquire properties that were not explicitly designed into them. Genetic modification (tampering with the sacred seed) is also obviously heretical, and in fact the entire field of developmental biology is a *very* suspicious discipline, as it attempts to explain and trivialise what is an evidently ineffable process. All of biology would probably be held back to the equivalent of our mid-19th century descriptive "stamp-collecting". Building a machine from specs is 100% fine, no matter how complex it is. It is obviously made, and therefore not alive. [Answer] # Injury is the gateway. Modern religious groups are fine with people and priests getting prosthetic attachments. Religion doesn't protect you from being sick. It might become very common to get cybernetics to help improve health and deal with sickness. # Don't ask don't tell is the end. Because cybernetics is so useful a lot of people might get augmentations without injuries. It may well be socially unacceptable to cyber up with no injuries, so most will vaguely hint at injuries. Most religious places won't dig into it, because they recognize the value of cybernetics. The socially acceptable view on it is that cybernetics is just done for handling illnesses and chronic pain, and that almost everyone who has it was injured, and that prosthetics are just like for like replacement of limbs. Talking about how you got augmentations for enhancement of function is a massive social faux pas. [Answer] ### What is AI? Exactly where you freeze "machine learning" requires you to define what elements of machine learning are and aren't halal, and this is going to be complicated. I'll just state as unambiguous fact that we don't have "advanced" AI yet. We have various flavours of machine learning which are able to be trained, by humans, to carry out some highly-specialised tasks with some acceptable degree of accuracy. We also have enough processing power that you can brute-force-hack simple pattern-matching tasks like chess. That's it. That's all we've got. Nothing more than that. When did we start getting that kind of machine learning? Opinions will vary, but a good starting point would be with [Kalman filters](https://en.wikipedia.org/wiki/Kalman_filter). These started to be used in the 1960s, as a method for control electronics to learn the performance characteristics and environmental factors when controlling a ship, aircraft or spaceship, by comparing expected motion against actual motion and changing its internal model of the system to match its observations. Does this count as AI, since it's doing what a skilled helmsman or pilot would be doing? If so, you need to roll back your technology cutoff by 60 years for Kalman filters. You also need to allow for your society to have a lot more people in decision loops than we currently have, from warfare to vehicle control to industrial manufacturing. And in practise your cyborgs are going to have a lot of problems moving if you take this away. Almost certainly you'd need an inherently-stable cyborg platform (e.g. four wheels) instead of anything inherently-unstable (e.g. legs). If you want to be even stricter, you could even consider [closed-loop control](https://en.wikipedia.org/wiki/Control_theory) to embody machine learning. It allows machinery to react to its environment and change its response accordingly. This could invalidate machinery as simple as [speed governors](https://en.wikipedia.org/wiki/Governor_(device)) on engines; and if you take out speed governors then you can basically rule out water, wind or steam power and all forms of industry and modern technology, so anything as advanced as cyborgs is right out! So you see that this isn't exactly a straightforward situation. Voice activation is a neat trick, sure, but that's just another brute-force hack. It's nothing that hasn't been around since the late 70s - it's just got better hardware and slightly different details for the same methods. Don't be fooled into thinking Alexa and Siri are AI, simply because they can (mostly) recognise human speech. All they're doing is some audio processing and pattern-recognition lookups - there isn't any concept of meanings behind it. If you define AI as something closer to machine consciousness though, the situation becomes very different. We are still a long, long way from that! Not only do we not know how to do it, we don't even have a well-defined path to get there. The best we can say so far is that we have developed a lot of technologies which, whilst being useful in many specialised contexts, give us examples of what consciousness ***isn't***. I wouldn't bet against someone developing strong AI in the next 50 years, sure - but famously it's been "10 years away" since at least the early 1970s, and still the best we can say is that we've found a bunch of different technologies which are useful in their way but are just different flavours of dead end when it comes to actual consciousness. [Answer] I think a simple reason would be this religion won't allow humanity to play to be gods: * Manmade sentient beings (AI) are an abomination. * Modify the very essence of already existing living beings (genetic engineering) is another abomination. On the other hand Cyborgs are just human beings with advanced prosthetics, you are not creating new species. If a *peg leg* is allowed, there is no reason to allow a nice titanium version with joints and servos. ]
[Question] [ This is a follow up from my [earlier question](https://worldbuilding.stackexchange.com/questions/225686/will-people-keep-drinking-alcoholic-drinks-even-if-they-dont-get-intoxicated-an), in which a virus has wiped out humanity's ability to get intoxicated or high. During the peak of the pandemic, as more and more people lost their ability to get intoxicated, would there be a mass event of withdrawal from people that are drug or alcohol users? I'm sorry if this question seem ridiculous, as I'm not that knowledgeable on the topic. [Answer] It depends on both the specific drugs and how the virus works on a physiological level. Not all drugs cause withdrawal, and those that do, do so through different mechanisms. If you want the effect to simply work like everyone quitting cold turkey, the virus might increase the ability for the liver to metabolize toxins quickly. This will cause the drugs to break down before they can impact the brain. In such a case, people would experience normal withdrawal symptoms. Would this cause a mass withdrawal event? That depends on how many people are addicted to drugs, but I would say that yes, there would be enough people experiencing withdrawal to create a serious health crisis. Let's ignore most drugs and only consider the most prominent one, alcohol. [This page](https://worldpopulationreview.com/country-rankings/alcoholism-by-country) shows percentage of the population with an alcohol dependency by country. Outside of northern Africa and the Middle East, most countries average around 5-10% of the population (some, like Russia, being as high as 20%) and this is plenty. Alcohol withdrawal is serious and can include anxiety, hyperactivity, hallucinations, and death. While I could not find the frequency of each symptom and how well it translates to the aforementioned numbers, even 1% of the country getting sick at once is a *huge* amount of people experiencing illness, which can threaten the integrity of the medical system if it happens in too short of a period. You might be able to reduce the impact by slowing down the progress of the virus so they aren't all affected at once. The fact that the virus is only really *dangerous* to people addicted to alcohol, but people who enjoy drinking would obviously not want to get it, means that it's anyone's guess how effective this would be. It is also worth noting that the virus' mechanism will probably render common psychiatric medications ineffective, as there is a great deal of overlap between these and recreational drugs (in fact, many prescription medications are used for recreation as well, and it's unreasonable that the virus would be able to differentiate). Even ignoring withdrawal, the direct impact of the virus will cause a lot of problems as people who keep their mental disorders in check with drugs will find them ineffective all at once. [Answer] **Small but significant** Just looking at alcohol, in 2015 it was estimated that 2.6% of people over the age of 15 suffer from alcohol dependence, the vast majority of them male. That's roughly 170 million people, if I have my population demographics calculated correctly. WHO estimates that about 35 million users of psychoactive drugs are affected by drug use disorders, meaning harmful use pattern or dependence. Just because it makes for a nice round number, if we assume that there is an overlap of 5 million people who are dependent on both psychoactives and alcohol then there are around 200 million people worldwide who will be significantly affected to some degree when their drug/s of choice no longer affect them. This does not include groups such as tobacco users - from my observations of people who have quit smoking there will be a lot of very cranky people out there who did not plan on quitting, albeit less than there would have been a few decades ago. **Reactions** While some people with drug dependency may find their new condition to be a blessing, those who have been using drugs or alcohol to deal with pain they cannot cope with any other way may react very badly. Even with rapidly deployed therapeutic support, it is practically inevitable that there will be millions of additional suicides, accidental deaths due to overdoses of substances that no longer provide a high but are still fatal in large doses and accidental deaths from other practices that create an altered state of mind through oxygen deprivation. (Desperate people will try anything, no matter how dangerous.) Out of all the hundreds of millions of people on the planet who miss their drug use (and the suppliers who consider them to be a commodity), someone is unfortunately bound to revive "recreational" research into direct stimulation of the pleasure centres of the brain. It will take some time, but eventually the "wireheads" envisioned by Larry Niven and other SF authors will come into being, unless someone comes up with a cure for the virus that has affected humanity. [Answer] Let's talk a little about intoxicants and why it's a Really Bad Idea™ to mess with them like this. The most common legal intoxicant on the planet at the moment is alcohol. Alcohol is a poison that interacts with your brain chemistry, monkeying with the production of various neurotransmitters. It suppresses the release of glutamate, a neurotransmitter responsible for increased brain activity and energy levels, leading to a general slowdown in your reactions and thought processes. Next it increases the production of GABA, further reducing energy levels. These are the reason alcohol is classed as a depressant. On the other hand it also increases the release of dopamine, the pleasure chemical, in the reward center of your brain. So your reactions are slowed down, your get clumsy and tend to fall over things other people can't see, but you feel really happy about it. And that's just one of many. Your virus has to do one of two things: rewire the entire chemical system in the brain to make it immune to these effects or change the blood/brain barrier to prevent *all* intoxicants from entering. From a biochemical perspective no virus is ever going to be able to achieve either of these. But just for the hell of it, let's assume that they could. The first option is a big ask, and almost certainly fatal. We're not just talking about blocking a few receptors here, you're looking at recreating the brain pretty much from scratch to use an entirely different set of chemical processes. Every part of each of 86 billion or so neurons in the brain needs to be altered to use entirely novel chemical processes. All of the glands in the body will need to be changed to produce the new standard chemicals, etc. I couldn't even begin to list the hundreds of thousands of new reactions that you'd need at the end of the process, but I can tell you flat out that there's no way you're going to rebuild a human body over a few days and have it functional the whole time. Either your body manages to fight off the infection - making it ineffective - or you die, no middle ground. The second case could possibly be done, and wouldn't necessarily be fatal, but it's going to cause serious issues. Firstly, chemical withdrawal just as bad as going cold turkey on everything they take. For most of us that's not a problem, but anyone with severe chemical dependence is going to have a really bad day. Or month. Some of them will die because the medication to help them with their withdrawal is also blocked, since it's generally an analog of the drug that screwed them over in the first place. No synthetic analogs to help trick the brain's chemistry into thinking it's being gently eased off the addiction, just a hard stop on the chemical you're dependent on. Not a fun thing, by all accounts. Of course you're not going to get *all* intoxicants this way. While most common intoxicants are poisons that mess with your brain chemistry, a few are things that your body produces and needs for healthy operation, just at levels well below the point at which hallucinations and so on occur (looking at you N,N-Dimethyltripamine). You can't close off the brain to everything, it'll shut down in seconds. Any channel you leave open will be identified and a whole new batch of intoxicants will be on the shelves in time for <insert holiday of choice>. Another down-side of the whole thing is that there are a lot of drugs that fall into the 'intoxicant' category when used to excess that in other situations are actually quite important. Opioids for pain, Benzodiazepam for a variety of issues, Dazepam (or Valium if you prefer the branded pills) for a bunch of things... and so on. Millions of people around the world are living healthy, happy lives because their doctors prescribed the right dosage of happy pills, and your virus is going to take that all away. (And that's not counting the millions more who are just prescribed the pills because their doctor gets kick-backs.) How many people are going to handle life when they're suddenly dumped back into their worst mental states with no warning and no way to deal with it? And since we're tangentially approaching the topic, let's have a quick glance over at psychological dependence. The habitual drinkers might be OK once the dry terrors are over - they can still drink after all - but the ones that have a deep conviction that they need to get drunk/high/wasted/whatever to get anything good out of life, to enjoy themselves or just to unwind... they're going to be damned hard to deal with. Don't underestimate the power of mental convictions and conditioning. I know people who can go months without touching a drop but hit the bar to blow off steam when the stress levels get high enough, and some of them are going to go off the rails in terrible ways if they can't relieve their stress that way. So yeah, I don't want to live in that world. I don't drink much, I don't take drugs recreationally and I'm not dependent on medication for (what I will laughingly refer to as) my sanity. But although I don't have a real dog in the fight, I really don't want to watch the world go even more insane than it already is. [Answer] **No withdrawal symptoms** As told [here](https://my.clevelandclinic.org/health/diseases/16652-drug-addiction) > > People feel intoxicated after using drugs. Over time, the brain is > changed by drugs. The brain becomes desensitized to the drug so that > more of the drug must be used to produce the same effect. > > > You told that "virus has wiped out humanity's ability to get intoxicated or high" which means that changes made by the drug in brain are reversed and will not occur again. The result is that alcoholics will not suffer any withdrawal symptoms because the brain is not demanding drugs anymore. [Answer] (Refer to my other answer for why you shouldn't do this.) Now that we've got a bunch of reasons not to, here's how you can do this without breaking the world and killing a ton of people. Instead of a virus, infect the planet with a smart nanoplague. I know, nanotech isn't actually magic, but it's a heck of a lot more believable than a virus that stops people getting drunk without doing anything bad to them. The initial 'infection' period is due to the nanites scavenging various things from your blood, lymph fluids and fat stores to build manufacturing and storage devices into the lymphatic system, slightly increasing the size of your lymph nodes in the short term and causing inflammation in various places in the body. In the second phase the nanofactories in your lymph nodes start to produce and stockpile toxin binders that will capture and neutralize various chemicals in the blood stream. These are stored in capsules throughout the body, attached to the circulatory and lymphatic system. When the levels of target chemicals reach certain levels the appropriate stores open and flood the blood stream with toxin binders specific to that chemical. Each binder vacuums up a few molecules of alcohol or PCP or whatever and then makes like an expired blood cell and is collected by the body's waste disposal processes, ending up in the bowel for convenient disposal later. There are a few upsides to this system: * You can tune the activation levels to allow a small amount of various chemicals through - you can get a slight buzz from a bottle of beer but several bottles isn't going to do much for you. * The initial build-up of toxin binders can be slow enough to wean addicts off slowly - a couple of weeks for alcohol, maybe a slow few months for crystal meth. * The system could adapt to produce more binders for toxins it detects and less for ones it doesn't, so you're not wasting storage or production on binders that aren't ever used. * Properly tuned the system allows for medication, and we could include some sort of trigger to shut it down temporarily in situations like surgery where the anesthetic and pain relief would normally be blocked. * Can also bind to non-intoxicating chemicals like cyanide, arsenic, dioxin and so on. Downside? You can only store a certain amount of each type of binder, so if you drink a few bottles of high-proof spirits you'll reach the limit of what it can do. Getting smashed is still a possibility, it just gets a hell of a lot harder to achieve. And more dangerous, since you can't be absolutely certain of how many bottles of Old Neuron Embalmer #7 it'll take to get past the cleaners. Expensive habits will get a hell of a lot more expensive, and probably kill a lot more people. And of course there 100% will be a black market trade in whatever it is that lets you switch the system off during surgery. You'll get a modern equivalent of opium dens where you can pay to have the system disabled long enough for you to get high on your drug of choice, but this is going to be way out of the price range that the huddled masses can afford. Intoxication will be the domain of the rich... until someone finds a way to bypass the system cheaply. Eventually we'll find all new drugs to replace the ones we used to have. Be prepared for all sorts of nasty street drugs, and some quite interesting designer drugs, to start popping up in a couple of years time. Now that would be an interesting world. Let's go with that version :P [Answer] ## The virus would kill everyone it infects Intoxication happens when a foreign substance causes a dopamine response. In order to make a person chemically unable to feel intoxicated, the virus would need to destroy, block, or otherwise disable all the dopamine receptors in your brain... but your brain needs these receptors to function. As the the virus kills off your dopamine receptors, the virus would basically act like getting very rapid onset Parkinson's Disease. The patient would experience symptoms like depression, schizophrenia, psychosis, tremors, muscle rigidity, loss of unconscious movements, and finally heart or respiratory failure. Furthermore, intoxication happens across the whole brain; so, you can not just isolate the virus to disabling some specific part of your brain. Excitation happens in your frontal cortex, pleasure and abnormal memory patterns happen in your limbic system, disorientation happens in your motor, sensory, and visual cortexes and cerebellum. So, there are too many vital areas of your brain that are effected by intoxication for them to be selectively altered. You also can not change the way your body absorbs dopamine stimulating substances by just preventing it all from reaching your brain because most of what we eat is designed to activate dopamine receptors. Basic stuff like carbohydrates, fats, and proteins make you mildly intoxicated by triggering a dopamine response. If you block all intoxication, you also block the positive feelings you get from eating food; so... not only will addicts feel withdrawals from drugs, but normal people will feel withdrawals from food. At first people will feel like they are starving all the time because thier body is not receiving any confirmation of getting food; so, they will over eat then after a period of acclimation they will stop ever feeling hungry which will cause people to starve themselves to death. [Answer] For the nanoplague, there is a way to make drinking more booze than the binders can catch nearly impossible. Attach an enzyme to the binders, which destroys the drug. So they get free to be re-used and kill the next molecule. The enzyme should alter the structure of the binder. When it grabs a drug molecule, it gets in alarm shape, and will stay this for a while after the drug is destroyed. Binders in alarm shape will not be filtered out of the bloodstream. This should make flooding the system with drugs extremely difficult. Even if you manage to get drunk or high, the effect will last only for a very short time. The "new street drugs" problem is more difficult. Junkies usually do not want to be high in specific way, anything that causes a dizzy head will do. And they do not care about health damage. Therefore any household or industry chemical which disturbs the brain function is a possible replacement for alcohol, but with much worse side effects. ]
[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 3 years ago. [Improve this question](/posts/193288/edit) # Backstory So, the Kingdom of Maliscyle used to have an inquisition, to weed out the cult of the horned lord (a terrible demon). But... they found they were almost as bad as the cultists, as they just started doing what inquisitors are now known for. So, the inquisition was purged, and the kingdom settled for a time of peace and prosperity. ...Until the demon cults started flaring up again, and they remembered why they had an inquisition in the first place. So, the next king made a hard decision, and decided to organize the inquisition 2.0; now with less tortured confessions, guaranteed! ...But is it guaranteed? # Goal for the Inquisition The inquisitorial organization has two branches. One is basically the police, who enforce religious laws, cracking down on demon cults. The second branch is legislative and more ecclesiastical in nature. They decide what is and isn't heresy. In the past, this lead to them deciding whatever was convenient to them was heresy, and using the enforcement branch as hitmen. Now, though, they still need someone to decide matters of the kingdom's religious laws (freedom of religion kind of exists in Maliscyle). They don't want the king or anyone else to do it, because they think it's too much power for other government institutions. Instead, they're hoping to let the ecclesiastical branch handle it, but this time with some sorts of checks and balances to prevent the runaway corruption of last time. ## Proposed solution The general idea they had, was that the legislative branch is made up of a large council (about 300 members). Most actions require a two thirds majority, and passing a harsh law requires a 90% majority to agree. Their second idea for a check, was that if a large enough number of the nobility (including the king) disagree with the law, then it is annulled. The details would be rather complex, but the general thing is that as little as 18.75% of the nobles, if the king supports them, can annul a decision; if they're properly concentrated into one demographic. If the voters are spread out, and the king does not support them, then it could take up to half the nobles, 50%, in order to annul a decree of heresy. ### Police The police branch would be put under the authority of the secular police. In effect, it'd be just another branch of law enforcement, similar to NARCs. They also gave them the equivalent of an internal affairs division, to keep an eye on them. Finally, they removed a lot of their powers to torture for information, and reduced the credibility of unverifiable confessions of magical events, which were impossible to prove. They hope this is enough to prevent the inquisition from assassinating people with false reports. ### Outcome The general idea for the story was that, surprisingly, it seems to be working out. The inquisitors are checked by the king and nobles, so most of their decisions are semi-democratically approved by the oligarchy, without giving the nobles or king direct control of church matters. The close scrutiny of the inquisitorial police reduces corruption, until the corrupt feel quite out of a job. That's when the Horned Lord would spring his own plan into action, subverting their little dream society. # Question So, to clarify, there are two elements to this question: 1. How can the Inquisition be reformed to do its job? I offered one proposal I thought was interesting, but I wanted to hear others, and hear opinions on that proposal. 2. As an optional additional point, how do you think the Horned Lord could exploit the system I suggested, or the one you suggest, in order to break down the society? Most societies have some weakpoint that can be exploited, so a demonic influence could whisper suggestions and corrupt certain officials, or could send his cultists to infiltrate offices or take advantage of loopholes. In other words, I'd like you to describe a reform program for the inquisition, but to also point out the exploitable weak points of the system you present. [Answer] Institutions grow if they work to grow their own power, and shrink if they do not. Homeostasis is nearly impossible. In your case, you have an endevour that is extremely important. People will believe that whatever they do to make your inquisition stronger is justified, and others in opposition to it are helping the demon. To maintain some kind of temporary stability, you'll want to have multiple institutions with as many opposing interests as you can manage. In modern justice systems, there is investigation, enforcement, legislative, prosecution, defence, judges and juries. * A detective or a FBI agent is Investigative. They seek to find people who broke the law. * Enforcement is a beat cop or SWAT team. They catch people who broke the law. * Judges check that the rules are followed. * Legislative set the rules. * Prosecution proves that the Investigative successfully found someone who broke the law. * Defence proves that the Investigative didn't find someone who broke the law. * Juries determine which one of the Prosecution and Defence got it right. Each of these "institutions" has some opposing goals, and philosophically there is an agreement that all of these institutions are legitimate and deserve to have their goals exist. In practice they aren't as divorced as they look. Judges and Prosecutors and Investigators often end up in cahoots, "on the same side", and Investigative and Enforcement are grouped in many western countries (as "police", just different sub-jobs). Seek to generate separate institutions that jealously guard their independent from each other, and in the friction generate stability. I don't think it is important than the **same** split of institutions is needed. Like, a Jury of the People isn't fundamental to this balance; the fact that the Jury's wishes and wants as an insitution are distinct from the other institutions is, and that the Jury cannot be crushed by the other institutions, is. Your system only seems to have three institutions -- the king, nobles and the church. Far too much of the inquisition is centralized inside the church, and the king/nobles only set the rules. If the Church is finding the heretics, catching the heretics, determining if they are guilty, and determining if they are following the rules, then what does it matter what the rules **say**? You split the inquisition into two -- "Investigate" and "Enforce" on one side, and everything else on the other. You need more pieces. What other power centres do you have in your society? Is there a merchant class? Trade guilds? You need strong, independent institutions, in at lease procedural opposition to each other, throughout the system. Expect the institutions to develop animosity to each other and attempt to undermine the other institutions power. When your enemy is a secret cult that could legitimately infiltrate the other institutions, this is going to be crazy hard. [Answer] Accountability. All the Inquisition's actions are subject to review. For the determinations regarding declaration of heresy, outside experts in religions (and the Horned God's cults) review the evidence to verify if an accusation of heresy was justified. Their enforcement actions, likewise. And there's one prime law: an unjustified declaration of heresy and subsequent action is *itself* heresy and thus the same punishment would be imposed. You can think of a secular equivalent that states that if police investigators and/or prosecutors knowingly convicted the wrong person of a crime, they are then guilty of aiding and abetting the true criminal and thus are accessories to the crime and subject to the same punishment. [Answer] # The Inquisition is unfairly singled out As this thread from AskHistorians (which is moderated to only allow well-researched answers by real historians) says, the Inquisition was [not significantly worse](https://www.reddit.com/r/AskHistorians/comments/7wzb77/was_the_inquisition_as_cruel_as_everyone_thinks/) than what one found in the justice system of the rest of Europe at the time. It got a bad rap apparently because Protestants with an axe to grind took it out of context later and vilified them. (Not that, by the standards of the later time - or ours - what the Inquisition did looks *good* in comparison; it doesn't. It just wasn't *out of line* with what everyone else was doing back then.) It just took time for people to accept that torture really isn't a reliable way of sussing out guilt or innocence, and to develop better rules. # What this means for you So in your society there exist cults serving an actual demon that presumably are doing all kinds of horrible stuff hidden in the shadows. That sounds like a pretty good reason to have an Inquisition. It's pretty much the same reason why we have to have police: to maintain order. In other words - there does not have to be any real difference between your Inquisition, and any other kind of police force. Only their jurisdiction will be different. Just because we need police, though, doesn't mean they can operate without meaningful controls on them. And even though if (as many people say nowadays) those controls are lacking, that just means the system will have issues - that's no reason to get rid of it entirely. In our world, we have designed bureaucracies that split power up, leaving no one person in complete control of it. This solution brings its own problems, but it's the best one we've found so far. Your Inquisition has one clear advantage for it: The demon exists, and its agenda is terrible and terrifying. Make the Inquisition keenly aware that every innocent person that falls into their hands (because of course they will) only plays into the hands of their Adversary, and your Inquisition will naturally be highly motivated to co-operate with its equivalent of Internal Affairs. [Answer] > > now with less tortured confessions, guaranteed! ...But is it guaranteed? > > > **You have the right to remain silent (but nobody does)** In many modern criminal cases, the police will question you for days and lie that your buddy has ratted you out, and if you don't want a super harsh sentence you've got to rat him out too. There is no torture involved. If you wanted to make sure the defendant isn't tortured for a confession just **make any statement from the defendant inadmissible in court. Now you just have to figure out how to make sure witnesses are not harassed.** [Answer] ## The Inquisition's Corruption Stemmed from Unrestrained Powers These powers included the unrestrained power of interrogation, the unrestrained scope of authority, and unrestrained accountability for their actions. Unrestrained power of interrogation meant that they could torture a person to get information without ever needing just cause or a conviction. So, punishments could be served without trial or evidence. Even if they 100% knew a person was innocent, they could take someone and interrogate them to death... and even if they got a false confession, they would then have all the evidence they needed to bring that person to trial where they would be convicted and killed. One wide-spread example of this abuse was the use of the Inquisition to disfigure British Longbowmen. The French hated British longbowmen so much that when they captured them, they would turn them over to the inquisition to break their shooting fingers "just to see if they are heretics" before ransoming them back to England with everyone else. Next was their unrestrained scope of authority. Anything could be considered Heresy that was not Catholic. Since no two people ever believe the exact same set of things, it means that a general Inquisition can be used to root out any undesirable subculture... or just that person down the street you don't like. The Catholic Inquisition was not just purging Paganism, but every variety of Christian Church that taught anything that opposed the Papacy. So, you did not need to be able to show that a person was a witch to incite an investigation. You just needed to show that they believed something uncatholic. Lastly, Inquisitors were not accountable for their actions. Because they were sanctioned by the Papacy, whatever they did was considered above contestation. This meant they could knowingly do wrong without fear of reprisal. ## How this applies to your setting Since you say your inquisitors are like modern police, you've solved for the unrestrained power of interrogation issue. So your inquisitors can arrest, ask questions, and hold for a short while, but they can not harm or hold indefinitely without trial. Also, modern forensics has a lot of non-harmful tools for finding the truth that the old inquisition did not have. Your inquisitors could use Internet Search histories, GPS tracking, phone tapping, etc. to build a case on someone before they even know they are under investigation. So, by the time an inquisitor shows up at your door to arrest you, they have no need or torture you since they already have all they need to prove your guilt to a judge. You have also fixed the scope issue by limiting their authority to targeting a specific cult. This gives them much less leeway to abuse their powers going after groups that they are not intended to investigate. Thirdly, you've given them an internal affairs division to hold them accountable for their actions which solves the third major issue. All-in-all, it would be very hard for your inquisition to become any more corrupt than any modern police force. You'd probably see a few small town inquisition forces become incredibly corrupt here and there just like we see today, but by in large your inquisitors would be well meaning law enforcement agents doing the best they can to protect and serve, and your internal affairs would likewise mostly be well meaning law enforcement agents keeping the agency free of corruption. ## How would the Horned One combat this Inquisition? The best way to undermine a modern police force is by mimicking the actions of Anonymous and BLM ✝ where you stir up hate issues to make the police force seem like the real enemy. Every time a non-cultist gets killed in the crossfire, every false accusation, every failure is hyper publicized unto the point that the inquisition comes under too much scrutiny to properly do its job. Even if 1 innocent is harmed for every 1000 guilty cultists you eliminate, the only stories people will hear or care about will be where things went wrong. Then you further inflame the issue with things like Gender or Race discrimination. Historically, most witches were women; so, if inquisitors start profiling women for witchcraft, you could start slamming them for being a symptom of "toxic masculinity" or "patriarchy". Illegal activity is also most often seen among desperate populations; so, if most cultists are found in poor communities, you could make it look like the inquisition is targeting the minorities who tend to make up these poorer populations. Once you get to to the point that people do not trust the inquisition, you then follow up with campaigns like "defund the inquisition". Burying the inquisition in layer after layer of regulations to prevent them from ever doing any harm whatsoever combined with defunding them would mean you take away the tools they need to be able to actual subdue suspects wielding the arcane powers of the Horned One, but more importantly it would take away the tools they need to find the cultists at all allowing the cult to grow and thrive without adequate opposition. Not only does this give the cultists more freedom to grow in numbers, but it will also polarise the society making it easier for the horned one to attack the structure of the current powers that be. With everyone ready to turn on the current leadership, it makes inserting a new government more friendly to his agendas much easier. ✝ *This is not meant to say anything good or bad about the actions or motivations of such groups in the real world, only to point out the strategies that they use.* [Answer] Just like in our world, you need an independent judiciary as well as the executive (police) and legislature. The judges will help to prevent police excess and ensure that the laws are interpreted in a reasonable fashion. Make sure that none of the three branches can influence recruitment or promotion in either of the other two. [Answer] Don't make the religion the focus of your laws, make their practices the focus. Prosecute human sacrifices as murder. Prosecute animal sacrifices as animal cruelty. Make lobbying illegal. Enforce "separation of church and state" by prosecuting any official that makes a blatant or thinly veiled attempt to create laws that favor the cults. Mobs/riots that damage property and/or are violent against people have their punishments multiplied if done as a hate crime. Prosecute witnesses as accomplices. Prosecute influencers as treason or sedition. Also, you really want to go after the leaders, not the peasants they duped into joining the cult. You charge the leaders with the same crimes as anyone they have [under their influence](https://en.wikipedia.org/wiki/Racketeer_Influenced_and_Corrupt_Organizations_Act). You also give witnesses a chance to "get out of jail", but also have a "3 strikes"-like system. Some people might be at a ceremony the first time or didn't understand what was happening until it was too late. And have a system in place to make sure that "repeat offenders" are discovered. It might be reasonable for someone to get lied to and be talked into witnessing a human sacrifice once, but not twice. It might be reasonable to be in the room next to an animal sacrifice twice and not hear anything due to the party the acolytes are throwing, but not 3 times. An official repeatedly listening to the same influencers that gets his laws rejected and has maybe 2 chances to report them. Someone stating they were simply a witness, but reliable others say they participated gets their charges upgraded. Make sure that "bearing false witness" or otherwise "lying under oath" is a crime, to help prevent actual innocents aren't wrongly prosecuted by the lies of cultists. You want to avoid people [falsely denouncing each other](https://en.wikipedia.org/wiki/Spanish_Inquisition#Accusation) and you might even want to prosecute those making repeated false statements. [Answer] > > So, the next king made a hard decision, and decided to organize the inquisition 2.0; now with less tortured confessions, guaranteed! ...But is it guaranteed? > > > Of course not! The original christian mediaeval inquisition was "bona fide" created. Nothing but good "christian valour". Do you remember? Jesus Christ, the guy who said: Luke 6:29:If someone strikes you on one cheek, turn to him the other also. Luke 23:34:Then Jesus said, “Father, forgive them, for they do not know what they are doing.” People following him burned inocent people alive! No, no way it could work. Like people have answered above, you need an impartial secular judiciary to do the job the way a REAL christian could do. ]
[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/191332/edit). Closed 3 years ago. [Improve this question](/posts/191332/edit) So, what can I do to give dragons an advantage that will possibly shine through no matter what? Which part of them have I been neglecting while trying to figure out how they fly? Yes, their breath weapon. You see, my dragons don't breathe fire, they cast spells through their mouth (kinda like sorcerers in [Dorohedoro](https://en.wikipedia.org/wiki/Dorohedoro), though they used their fingers there). This "magic" usually takes the form of greyish smoke, which is actually a swarm of micromachines under the dragon's control. **Micromachines doing stuff is considered magic here.** There are many types of micromachines that a dragon's body can produce. Some alter their optical properties to create illusions, others can act as disinfectants or deposit onto wounds, creating an artificial clot. And most importantly, they can carry strong oxidizers, toxins, or medicine. This swarm lives in a symbiotic relationship with the dragon, using up some of their resources and life force (i.e: chemical energy, usually stored in fat and glucose) to power itself and replenish its numbers, never so much that it would kill the dragon. In the setting, dragons are meant to be the masters of magic. Like, some of their powers can't even be replicated by humans, or at least their version would be very inefficient and lack certain features. Keep in mind, humans also have magical smoke, though that has to work off of that human's life force. Dragons themselves are about as large as bigger horses (170 cm at the shoulders), and they can live for thousands of years. They're as intelligent as humans and while their scales can resist non-AP rifle rounds, that's about all their special biological features. **So, why are dragons, on average, more adept at using magic and why can't their spells be replicated by humans?** [Answer] ## Bigger is Better Since dragons are so much larger than humans, their micromachine swarms are larger as well. More micromachines allows for more power in the spell, as well as more processing resources available to the micromachines to achieve more complex effects. If a particular spell requires a micromachine swarm that can only be supported by a body mass of 700kg in order to be cast correctly, a 70kg human just isn't going to be able to pull it off. (This also opens the door to the possibility of "ritual" spells, with multiple humans (or dragons) networking their micromachine swarms together in order to cast more powerful spells jointly.) [Answer] **Legacy code** Dragon machines work fine with dragons. In days of yore the programmers who wrote this code took care to make sure it is so. This ancient and inscrutable code is larded with redundancies, fake bit, dangerous traps / pranks and other things. The code is much larger and more inefficient than it has to be. Modern dragons pretty much use it as received; it is intimidating to the moderns to try to edit this legacy code. The ancient coders had rare gifts and the result of their code is awesome. Humans find it easier to find ways to masquerade as dragons and fool the machines than it is to reverse engineer the crazy code to make their machines do what the dragon machines can do. [Answer] Maybe combine this with @Willk 's answer... **Dragons are super geeky coders**. They're supposed to be hibernating for decades in caves... Well, the big secret is the sliding door at the back of the cave, where they keep their computer labs and network farms. Any respectable dragon spends decades at a time honing his coding skills, or sometimes just chilling by playing an online **dungeons & dragons MMORG**. They even have high-stakes tournaments on the lizardnet. All this super techy geeky scripty codey stuff makes them better geeks wizards. [Answer] **Communication** It's all about Precision. Assuming the micromachines operate based on direct stimuli from the nervous system, the dragons' larger size allows the nerve-based signals to be spread further, allowing the micromachines to better triangulate exactly where the cloud is intended to go, and communication can occur over a spectrum (I'm assuming the machines are controlled by RF here, but it isn't really necessary) that humans are incapable of reproducing. Also, a horse-sized dragon with a human-like brain/mass ratio would have many more nerves available for the micromachines to interface with, allowing for the control of larger or more specialized swarms. Then there's the practice bit. A dragon, having practiced control of these machine swarms for thousands of years, has developed a better interface with the micromachine swarms, possibly even creating new nervous pathways specializing only in machine-biologic interface, while humans have to make do with a control system that also performs biological functions - an odd guttural sounding "language" perhaps, when humans try to cast spells. [Answer] The code is ancient and dragons have access to hoards of sample code written for long dead languages which humans are not privy to. They can sometimes be convinced to share the documentation for these long dead languages, which many nanobots are programmed to use, but it comes at a cost. Here is some code written in draconic: [![enter image description here](https://i.stack.imgur.com/PIKcg.png)](https://i.stack.imgur.com/PIKcg.png) The boss has permitted me to translate this in to human language. It was something like this ``` int explain_your_failure(puny_mortal human) { char* explanation = demand_explanation(human); if (!acceptable(explanation)) { devour(human); } return 0; } ``` It cost the translator an arm and a leg to get the full codebase translated over. Much time has been spent trying to reverse engineer this ancient script, and there were breakthroughs over the last 200 years, but a lot remains un-translated. [Answer] Nanobots are voice-controlled and don't deal well with human accents/pronunciation. Nanobots have been created as voiced controlled by dragons and therefore they use dragon language. However human wizards learn it in adulthood or teens making it heavily accented and they effectively speak a foreign tongue. What worse human throat is built differently so they cannot produce all sounds. The result is as if elephant tried to use voice control software. Nanobots being miracles of technology can guess what humans speak making it work in the first place but combination of physiological differences with accent makes only basic instructions possible - when Dragon can say "create fire in my mouth and move it outside using 50 km / h" humans attempting it would mispronounce "light a fire in your mouth and go out at a speed of 50 km / h" (I've attempted to translate the phrase between several languages) and be lucky if they end up with 1st degree burns while they stand in 50 km / h wind. The way the Humans deal with it is by creating a list of phrases they memorize that describe what they want to do - e.g. learning how to pronounce "light a fire in my mouth and move the fire out of my mouth with speed 50 km / h" so that nanobots can figure out what they want even if some words are not understood by nanobots. Dragons can say it however easier as they don't need to deal with voice recognition AND they can do it on the fly. [Answer] Perhaps the the dragons are totally formed of the clouds of the robots in some variant form or stage in the robot lifecycle. What else is a cell? It's rumored there are huge dragons which produce the "normal" ones in their image, and contain the true source of the tiny robots, but nobody has ever witnessed one. It could be that they hide about in plain sight with such powers and intelligence, but they'd need to make a mistake to be seen. [Answer] ## Dragon brains are different. Nanobot magic requires some complex\abstract\fractal\all of the above calculations performed in the mind of the caster in order to tip the bots on what you want them to do for you. The detail and correctness of these calculations determine if the resulting spell will be a success or if it will cause your arm to explode. Humans can do it reasonably well, but a quirk of evolution had made dragon brain structure be supremely more effective at cracking numbers, making every single one of them into, basically, mathematical savants. This, coupled with their larger size meaning a larger reserve of bots, results in them being able to cast more powerful and more complex spells. And also be *really* good at math. ]
[Question] [ Witches are born with various levels of mana, with some having larger pools than others. This determines the strength of their magic and the power of their spells. However, magic is complicated, expensive, and time consuming. Spells require specific materials and enchantments, and can take several hours to perform. Magic wands have two main functions. When a magic wand is properly crafted and enchanted, it creates an energy focusing tool. Runes for a specific spell are carved into the wand, which activate when a person is ready to use it. After it is activated, energy is channeled into the wand which will focus the energy into a beam that comes out of its tip. This provides a shortcut for magic to bypass the long and complicated steps by having a ready-to-go spell on the fly. There are some downsides to this. A wand is built to contain only one type of spell (e.g. fireball, levitate, etc.), and is not multifunctional. This limits the spells one has access to. The second problem is that wands only work for non-witches. Although witches that possess Mana create these magical tools, only those without magical abilities are capable of using them. I designed it in this way to provide a balance between witches and muggles so that one cannot dominate the other. However, I don't have a way to explain why those with magic can create magical tools for others, but be unable to naturally use it themselves. How can this be the case? [Answer] **Different wavelength mana** The energy is the same but the polarity is different. Mana coming from witch using a wand will actually cancel the magic from the wands even though both are expending energy. This combined energy will be wasted into stirring up the magic ether. The people who invented wands made it this way on purpose. With effort and research, a witch could start from scratch and make a wand that operated with the same polarity as their native mana but they are not motivated to do all that - they have mana powers already and also have brooms already to focus them. On the rare occasions a witch really must use a wand (because of some special and hard to duplicate power of the wand) she must do so by proxy, crafting a golem or some other intermediate that will not be so contaminated by witch-frequency mana. This entails a lot of witch mana and the wands still do not work as well as when handled by a mundane person, and so is usually not worth the effort. [Answer] The wand's mana has to connect to the user. The lack of mana in the user lets it reach it -- like a river running through a dry land rather than into the sea. The spell-like nature of the wand needs this. Other magical objects do not have some lack if they lack the same power. (Though it might have further implications for the development of magic.) [Answer] # Witches are natural magic users This may seem like a weird reason, as it would make sense that someone who's a natural without tools can be better enabled by tools. Give a math genius a calculator, you enhance their abilities. Give a runner a good pair of shoes, you enhance their abilities. Et cetera. However, what if witches were trained to do all that without tools? They've been taught how to do all the runes and rituals at lightning speed, and as such even placing a wand in their hand provides a great mental block. A true math genius doesn't need a calculator (or much time) to do all but the most difficult calculations (I remember on the show *Stan Lee's Superhumans* they found a guy who really excelled at mental math, to the point that professional mathematicians calculator input speed was slower than his mental speed. In that case, the extra device would be useless to him). # Social Stigma Furthering the previous point, witches were proud magicians when wands were first introduced, meaning they refused to touch them because only "those people' needed them for good magic. If you needed a wand, you were no better than "those people," who were so weak in mana they can't cast spells on their own. This kind of doctrine leads to a kind of social incest, where witches hang around other witches and only reinforce their beliefs, leading to wand makers to be seen as saints/missionaries that give those poor unfortunate souls the table scraps of witch society. Eventually, if enough people believe that it's impossible, then if witches are taught that way in school, they will eventually not be able to believe that they can use wands. Just think about what the US teaches about Soviet contributions during WWII. I find that if I can't explain something logically, then "tradition" or "taboo" (the negative form of tradition, ie "do/don't do this") is probably the most satisfying answer. # Magic from a wand isn't the same As much as a wand can hold the spell inside of it, there's a missing component that keeps it from being as effective as real magic. For example, in *The Irregular at Magic High School*, which has a similar dichotomy between Old and New magic, it's stated that old magic has extra rituals in it to provide extra effect, such as providing stealth casting during already long rituals. Perhaps wands lack some element that makes the spell more effective, meaning that witches, already naturally being able to do better wands can do, would go without (again, wands are witch table scraps). # Witches are magic specialists Witches act as magic specialists that use their high level of expertise to help with a wide variety of problems using magic. A housing contractor doesn't have all the plumbing, framing, electrical, HVAC, windows, foundations, and landscaping equipment, as they simply can't carry that around to every job. Well, your witches can't even carry around all the spells they need for regular usage on magic sticks, plus they can break, get worn down, etc, and then they need to get some more, which is a loss for them due to lost opportunity. Witches need their complex knowledge to turn a profit, doing complicated runes and rituals for specific spells. # Spells look cooler Your witches have an image problem. Muggles are scared of witches suddenly blasting away everyone with a wand spell, so Witch Council or whatever banned the use of wands. You now have witches looking cooler doing normal spells to be more entertaining rather than threatening. [Answer] # Wands short circuit with the caster's mana pool My first instinct was that a witch using one of these wands would experience a kind of short-circuit effect with their innate mana pool. The wand is a focus for environmental mana, which is less concentrated and needs to be aggressively harnessed for a spell to work properly. So if you give one a huge pool of mana to draw from, it uses every drop of it and burns itself out in a powerful backfire spell. What specifically happens depends on how the wand is attuned and how powerful the witch is: a fireball could cause an explosion, levitation could cause local gravity to invert for hours. Needless to say, most witches aren't willing to test out these effects, as they quite often mean death. It wasn't clear by your explanation if these wands are single-use prepared spells, or just attuned to cast a particular type of spell, but I think this works either way. The wand accumulates mana inside itself to cast a spell (either ahead of time or during the casting itself), and then anyone holding it becomes an extension of its available mana pool. This means that witches are prevented from using them *because* they are powerful enough to create them, which I think works well to explain this balance you want between magic users and wand users in a logical way. Witches would only make these wands as gifts for other people, if they truly had faith in the non-magical world. [Answer] # Witches Are Evolutionary Paraplegics All witches are paraplegics, born without the use of both arms because the genes for mana are linked to problems in the nervous system. Indeed, it is likely this weakness that lead them to evolve magic use in the first place. Witches cannot use wands because they have no use of hands. Giving your witches this disability will significantly change your story, but by stepping way outside the easy fantasy conventions, you’ll probably get some very unique and interesting characters. The slang of your world’s language can develop phrases that hinge on this key fact that forms your society: “as useless as arms on a witch”, for example. And if your story lasts long enough to reach into the cybernetic era, you’ll have magic users aligned with science instead of the usual trope of opposing it (“Witches were the pioneers of robotics and bio-enhancing gear...”), and your mundanes had best worry then. [Answer] **Wands let people access their mana pools. Witches can already do that** Everyone has a mana pool but only Witches have the necessary secondary superpowers to cast spells from it. This is unsurprising because mana is a form of *life energy* and every living person has that. The wand serves as a go-between and allows non-witches to access their pool. But witches already have that, so they have no need of a wand. This means a single witch is always more versatile than a single muggle with a wand, and probably more powerful, if the mana pool can be enlarged with practice. The *balance* comes from how muggles vastly outnumber the witches. While witches have no need of a wand, they CAN still use one if they want. It's just using the Wand of Fireball +3 is no more effective that casting it the normal way. They might carry around a sack of different *blank wands* as a form of disguise. Whenever they cast a spell they select a different want from the sack, wave it around, and cast the spell from their pool. In fact that sounds like a really good plot point. In this world the *wander* is a type of muggle who specializes in wand use. They travel the country with a wagon full of different wands, doing odd jobs as necessary. Our heroine has a natural aptitude for wand use and starts as an apprentice to such a wander. Then one day the master suddenly disappears. While searching for them, our heroine gradually loses and breaks her wands, and does some unlikely tricks, bending the effects of one wand to do something different. Then when in great danger, they cast a spell without a wand. Oh my gosh, how did I do that? It turns out the master was a WITCH ALL ALONG and was using the "wands" as cover but they were all just sticks. [Answer] Love this concept and it fills me with ideas! Maybe it's just plain annoying or downright uncomfortable or painful for a witch to try to use a wand? You wouldn't ride a bike with training wheels once you know what you're doing... it could be something along the same lines but a bit more visceral as opposed to just annoying or unnecessary. Another possibility, it's like putting two opposite ends of a magnet together, or something like that. A witch is born with mana, but humans are born with... human energy, which wands are excellent at concentrating into mana, but it's literally pointless for a witch to use. [Answer] # By Design Wands don't work for witches, because they were designed not to. Centuries back, some genius Witch despaired at the disparity between Witches and Humans. In order to help equalize the two races, she designed a tool. One that would allow Humans to use magic. She designed them to be simple to create, and limited to a single spell, so that her fellow Witches would not be too suspicious. She pointed out that is would make Humans more useful, but not too powerful. After all, they can just take the wands away, and each wand only does one thing. But in order to prevent her fellow Witches from growing more powerful by using wands themselves, she designed the runic language in such a way that wands would only work for Humans. She claimed it was an inherent limitation, gave them an explanation that sounded plausible but also went right over their heads. And proud as they were, the other Witches pretended to understand, rather than admit their ignorance. The basic concept is like a programming language. The first wand developer designed runic language as a high level programming language like C#, and encoded the Humans only element into the compiler and binary code equivalent. The other Witches can write programs (make wands) in the runic language, but don't understand the underlying structure that builds a spell from the runes supplied. (Of course, that leaves the door open for a new genius hacker Witch to figure this all out and maybe make some changes). [Answer] Perhaps the witches don't use wands because they don't need to. Maybe they can use them, but it is actually more difficult for them to use a wand than to do the same thing naturally through their magic. Finally, I really dislike the current trope in fiction where all female magic users are called witches. Are all your magic users female? [Answer] I think, that it have simple reason: * the magic wand works like antenna * the magic wand have a handle, which should be held in palm and "sip" magic energy thru hand from the body of its user (so no infinite fireball stream, you have to rest to recharge yourself after few spells) * the rest of wand is covered with runes, which sips and focus the energy to create desired magic effect * it would be (in theory) possible to make much larger "wands", that would be able to sip directly from the body (forming more powerful spells), but in practice there would be really unmanageable and it would be terrible to discover the right combination of runes to form the spell correctly and will not destroy the user (and that would be really error prone anyway) - think of cracking 3 letter password by brute force (too some time, but relatively easy) and 300 letter password the same way - basically impossible On the other hand the witches are able cast the spells naturally - their all body is able to emit and form spells * so witches **would** be able to use the wands, but then the spell would be powered just by palm, not by full body and much less powerful. Also it would be less effective to cast (lots of mana just burned on powering the wand itself) and really unpleasable for the witch (which would be artificaly drained from the palm without good control of that process and with rest of body itching, as the mana is forced to flow in "wrong ways" * so any witch would try to avoid using wand. (Get 1MP effect for 10MP and itching body instead of 10MP effect? Why?) * but for non-witches it is the only way (1MP effect + some itching, or no effect at all) * it also means, that witches are able to cast more, or more powerful spells - they are witches after all * but as there are more non-witches, their sheer number would provide balance in efectivity - it is easier to deflect or redirect one more powerful spell at time, then deflect each and every of one hundred less powerful spells at one time [Answer] Mana occurs naturally in living beings (witches), not in lifeless objects, and the containment measures necessary to bind it into an artefact have an unfortunate side-effect. In order to keep the wand charged and stop its mana 'leaking' out in between uses, it must be encased in a kind of mana-repellent field. Close proximity to this field can be extremely harmful to witches, whose entire bodies are infused with mana. The field is only activated in the final moment of the wand-manufacturing process, allowing witches to craft the items but not use them. This solution has the interesting corollary that wands will affect witches in inverse proportion to the individual's power level. A witch born with a weak mana pool might resort to using a wand in an emergency, suffering only a nosebleed and a crushing migraine in consequence. If an extremely potent spellcaster tries to wield one, however, she risks instant death as the wand reacts with her massive mana pool with potentially fatal results. [Answer] **Runic script use Blood magic** Runic script is an archaic form of magic predating mana manipulation that was used in ritual magic. One day, the first witch managed to bind/absorb ambient mana by marking it with her life force. Mana Manipulation was born. Mana can be replenished naturally; life force does not. Meaning using blood magic is reducing their maximum potential. In addition, Witch tend to protect themselves constantly against lifeforce drain. Without this constant protection, an army of fodder could use number to cripple a powerful witch using life drain: even if the battle is won, the individual is lost. Sadly, it’s easy to mistake the effect of a slight continuous vitality drain for tiredness. Meaning if an enemy army won’t do it, a political enemy could. Everyone has life force but not everyone has knowledge. Muggles could use blood magic but don’t know how. And even if they managed to learn it, miniaturizing runic script into a wand is by no mean easy with mundane mean. They can’t have new wands without a witch crafting it but even if the witches stop producing them the existing one aren't limited by charge. [Answer] A wand can only be made of a material with very specific properties in relation to the ambient magical field. Maybe one of the following is true: * In practice, this means there's one particular wood out of which wands are made, and witches are simply naturally allergic to that wood (as they might be to peanuts) for some reason: possibly some unlikely genetic coincidence, or possibly because the situation was specifically set up this way in the distant past somehow. * Proximity to a material with the magic-warping properties required of a wand causes all of a witch's magic to vent out rapidly into the local distortion. * A witch's body is sustained by an aura of magic; when the ambient magical field is distorted, the body very quickly starts to fail. I'm basically imagining the relation between wand and ambient magical field to be like the relation between a black hole and the ambient gravitational field. Witches can manipulate the field, or even perhaps are partially *sustained* by the field, but a sufficient distortion causes them harm. [Answer] Witches hates men (especially for Spanish Inquisition and Salem's Witch Trials), and touching wand insults them, because they consider it a phallic symbol of male domination. [Answer] **Tazing the Computer** Casting magic and enchanting objects is fine-detail work, requiring careful and precise application of magic, exactly the right magic in the right place. To become a witch, they or another witch must shape their magical abilities in subtle and delicate ways. building and training a selection of tools, like programs and data structures in software design. A wand uses the mana pool of its user, but drains it forcibly. Forcing the floodgates wide-open and anything in the way gets wiped away. This isn't a problem for a non-witch, they weren't doing anything fragile with their magical abilities. It's catastrophic for a witch, the torrent of magic simply destroys their fine-motor-control for spell-casting, essentially removing all the careful work that went into making them witches in the first place. Like applying a Tazer to a computer. Sure it can channel the lightning, but you just lost your design software and controls for the 3D printer... [Answer] **Witches have no natural mana, but they can manipulate with mana of others** **WARNING: Possible spoiler** Answer to this might lie in the *Night Watch* series from *Sergei Lukyanenko*. In this series, there are Others, people with supernatural abilities. Later in the series the protagonist learns how does magic actually works. Its not that the Others have higher magical background than muggles, they have actually lower magical background, which gives them an ability to manipulate with mana to compensate for. In this case, magic wand is just a channeling device to channel mana for a specific effect. Muggles have high magical background, so they can use wands without problem. Witches on the other hand do not have (much) mana. When they cast spells, they weave mana from neighbouring sources (items, plants, animals, people) to cause the effect of their discretion. The more experienced witch, the more is she capable channeling magic from other sources and thus more experienced in creating a better channeling devices -- wands. [Answer] **Its normal for people to make tools they can't use themselves.** * Adults make clothes for babies, but we can't wear them. * Fender (the guy, not the brand) never learned how to play guitar. * Humans make prosthetic limbs for animals, that can't replace our own limbs. I don't see a need for a magical explanation for how the witches could create tools that they themselves could not use. They do need motivation though, like money for their craftwork. I think there's a problem with your concept though: You say: *"energy is channeled into the wand..."*, and then *"only those **without** magical abilities are capable of using [wands]"*. If by "energy" you mean some kind of magical ability, then how are the not magically-abled supposed to use the wands? If energy means something non-magical, then I'm lost... but if my suspicion is right than I think you either need to have the wand contain the magic it needs for the spell (like a battery, possibly rechargable), or your non-witches will need at the very least some kind of passive magic "activating" ability. [Answer] Maybe it's not the witches making the wands... Maybe the wands are being made by normies, but they have to trap part of a witch's soul inside a wand. Then maybe somebody using a wand is like walking into a haunted house. A normie can walk into a haunted house and be like, "This is just an ugly house," because they can't see / sense any evil spirits within - and the spirits, since they're effectively invisible, leave the normie alone... but when a psychic who's sensitive to spirit stuff walks into one, they immediately get attacked by the evil, angry spirits, because the psychic can see / sense them, and the spirits are all like, "Oh, you can SEE me? I'm pissed and I'm taking it all out on you. It's ON!" So... Maybe a normie triggers a wand, and the bit of angry witch soul trapped inside can't do anything to the normie... but when a witch with her link to magic grabs a wand, the bit o' witch soul in the wand goes all angry ghost and lashes out. Maybe even tries to swap bodies. [Answer] Like charges repel. Magic can have a charge like static electricity. A device crafted by a mage will have the same charge as its crafter. If they try to use a device made by someone with the same charge the magic in the device will work against the magic in the mage, perhaps giving them a nasty shock. This could require that they wear magic-insulating gloves when handling completed devices. Muggles, being magically neutral, don't have this problem. They can just pick up a magical device and use it. Now, you could have different mages with different charges, so they could use a device crafted by a mage with a different charge, but which charge is generated might skew heavily in favour of one or another, so even though it's technically possible, other mages with different charges are so rare, most mages never meet one who can make devices they can use. ]
[Question] [ Sorcerers possess the ability to sense, generate, and manipulate energy; however, their abilities are largely limited to controlling energy that they/other sorcerers have created, and not naturally occurring energy. So a sorcerer can't extract energy from a natural fire and turn it into kinetic energy or turn a human into a Popsicle with a snap of his/her fingers (not really relevant to the question, but for the sake of clarity). What long-to-medium distance methods of communication might these sorcerers develop, in a medieval-like society. I'm not referring to mere visual-range signals with pre-determined meanings or short-range auditory communication, say by amplifying sound waves, but actual exchanges of detailed information over larger distances. Edit: A sorcerer's range for sensing energy is about 100 meters and half that in order to manipulate the energy. [Answer] With radio, they could cause electrons in their local vicinity to vibrate at specific frequencies which would generate radio waves. These waves would then span the distance between the two communicators at the speed of light. They could even manipulate the waves themselves to be sure they are moving in the right direction. So it would work just like a radio: 1. The messenger manipulates the electrons which causes the wave. He then directs the waves to travel to a specific region. 2. The waves travel at the speed of light to their destination. 3. The receiver detects the waves and manipulates electrons in his area to decode the message. [Answer] I am going to steal Eth's comment to eternalize it as an answer: > > Via earthquakes, of course! – Eth > > > This works regardless of the time setting. Medieval people would never understand radio but Earthquakes would be something really concrete to them. They could then develop some sort of wizard morse code, or better yet, use earth or stone golems as modems. Some advantages of using this method: * Signals travel 2 to 8 km/s on the crust, and up to 13 km/s in the mantle. They also follow straight lines to the destination. That is not only faster than a messenger on a horse or mail pidgeon - it is faster than sound in air! * Very good signal-to-noise ratio (except for those living in the Andes); * Omnidirectional, so perfect for broadcasts and group chat; * Can be modulated and filtered by amplitude or frequency to allow for different channels, so that quake conversations don't interfere with each other; * Can double as a weapon if you don't like the recipient. For anyone thinking this is a joke answer: seismic activity doesn't have to be something that shatters the Earth and damages buildings. **Most seismic activity in the world is so weak we don't feel it.** And the OP said at the start of the question: > > Sorcerers possess the ability to sense (...) energy; > > > Toph and the republic era earthbenders from Nicklodeon's Avatar come to mind, with their seismic sense. [Answer] Maybe using the whole quantum entanglement idea. <https://en.m.wikipedia.org/wiki/Quantum_entanglement?wprov=sfla1> I think this would work with your rules of being able to sense and manipulate energy They could have a system of manipulating the energy locally that would then immediately have an effect on the energy in another location. It's a loose interpretation of the principle, but seems close enough [Answer] # A wireless telegraph Each sorcerer has a special box or slate they've created made of materials they can manipulate in color or light. Just very simple, like early telegraphs. Now they can spell out messages in Morse Code. This code was not yet invented in Medieval times, but solely because there was no need for it. It would not be difficult to come up with a concise system for communicating digits. Morse Code uses 3 states: long, short, and off. That's all you need. A servant on the receiving end could transcribe the incoming message. With the right buttons and levers, a servant on the sending end might be able to transmit the message, if the magic can work that way (if the sorcerer doesn't have to stand there and will each mode change into being). # A wireless teletype A more sophisticated version could show letters on the receiving end. Single words, like a teletype, would be even better. I'm imaging something like a [Liquid Crystal Sheet](https://www.arborsci.com/products/liquid-crystal-sheet) only one made from materials available in the era and that uses manipulations of heat from below the glass to form letters. Glass was available in Medieval times, though it was expensive and not the same quality we are used to. But some magic may help in making clear flat sheets (about the size of a tablet). [![enter image description here](https://i.stack.imgur.com/9qkk0.png)](https://i.stack.imgur.com/9qkk0.png) # Or perhaps an Etch A Sketch If the sorcerers can finesse small lines that stay until the entire thing is reset, they could communicate some pretty complex messages. [Etch A Sketch](https://en.wikipedia.org/wiki/Etch_A_Sketch) was a common children's toy back in my day. It uses a glass screen and aluminum powder. No electricity. You "reset" it by shaking the screen. If your sorcerers can manipulate magnetic energy (and use iron powder), this could work. [![enter image description here](https://i.stack.imgur.com/RA4Ok.png)](https://i.stack.imgur.com/RA4Ok.png) [Answer] # By using the Pen of Flame Sorcerer A and Sorcerer B wish to communicate at a distance. * "A" conjures a flaming pen. * "B" senses that a flaming pen (as he has the ability to sense energy created by sorcerers). * "B" then creates a flaming pen of his own which "A" senses. * They each place the pen on a nearby scorchable surface * They exchange control over their flaming pens so that the other sorcerer can burn messages into being. There are probably similar and simpler ways for them to do this, but if you're a sorcerer and can use a flaming writing instrument, why wouldn't you? [Answer] Depending on how much you care about being overheard and how much of an issue efficiency is, you could use something akin to Morse code or tap code... with lightning strikes or something of equivalent brightness. Since this is the Worldbuilding SE, the fact that this would be *literally awesome* can't be ignored. Quick search says that your average lightning bolt is five miles high... some quick math says you're going to get about 400 miles. ]
[Question] [ ![enter image description here](https://i.stack.imgur.com/HrIcH.jpg) How effective are these guys? And could they somehow be considered the predecessor to the modern tank just as the horses of the medieval age were? [Answer] Not so much the predecessor of the modern tank as the predecessor of the [technical](https://en.wikipedia.org/wiki/Technical_(vehicle))\*, used in the same environments for much the same purpose. It carries the largest gun you can get into the area in the fastest possible way. Effective against infantry but not against heavy fortifications. For those worried about the camels running wild, apparently you lie the camel down and fire sideways using the camel as cover. [![enter image description here](https://i.stack.imgur.com/UEPk7.jpg)](https://i.stack.imgur.com/UEPk7.jpg) It's a desert specialist unit, used as mobile artillery in places you wouldn't be able to get heavy artillery to. > > The zamburak became a deadly weapon in the 18th century. The Pashtuns used it to deadly effect in the Battle of Gulnabad, routing a numerically superior imperial Safavid army. The zamburak was also used successfully in Nader's Campaigns, when the shah and military genius Nader Shah utilized a zamburak corps in conjunction with a regular artillery corps of conventional cannon to devastating effect in numerous battles such as at the Battle of Damghan (1729), the Battle of Yeghevārd, and the Battle of Karnal. > > > A zamburak consisted of a soldier on a camel with a mounted swivel gun (a small falconet), which was hinged on a metal fork-rest protruding from the saddle of the animal. In order to fire the cannon, the camel would be put on its knees. The name is derived from the Persian word for wasp zambur (زنبور), possibly in reference to the sound earlier camel-mounted crossbows made. The mobility of the camel combined with the flexibility and heavy firepower of the swivel gun made for an intimidating military unit, although the accuracy and range of the cannon was rather low. The light cannon was also not particularly useful against heavy fortifications. - [Wikipedia](https://en.wikipedia.org/wiki/Zamburak) > > > --- \* A pickup with a machine gun on the back. [Answer] Pack animals have been used to *transport* weapons for a long time. Of course the pack saddles were not designed for firing from the horse or mule, the gun was supposed to dismount. Compare this writeup of [1944 US horse cavalry](https://en.wikipedia.org/wiki/United_States_Cavalry#Horse_cavalry_rifle_troop_1944), especially the Machine Gun platoon. Or look at this picture of a [machine gun pack saddle](http://www.reillysbattery.org/MG%20Page/MG3.jpg). For that matter, look at this image of [elephant-carried guns](https://www.britishbattles.com/wp-content/uploads/2018/07/14-Elephants-en-route.jpg) in Abyssinia. ]
[Question] [ Because my setting is incredibly varied, I've been advised against attempting to ask this in a single question, and have broken this up into a series. Each context will be roughly analogous to a setting in my world(s). Imagine that you live in France during the stone age. One day, you and five friends have the ability to magically induce [redox reactions](https://en.wikipedia.org/wiki/Redox) at-will. Each person can use this ability to effect a total mass of 3 tons, per day. They can control the speed of the reaction, the scale of the reaction and remove the need for any activation energy. The goal of you and your friends is to exert economic dominance over neighboring tribes using the least amount of this power. You and your friends are in complete agreement about this goal and the means of achieving it. Nobody will be founding new religions around you or your powers. You have no foreknowledge of history. There are no particularly important figures for you to assassinate. Your environment and tools are otherwise typical of the time and place. The power can be used on yourselves, inanimate objects, and non-human animals. How would you do this? [Answer] Photosynthesis counts as a redox reaction. Since you have said that all activation energy is negated, sunlight's natural limit on the growth rate of plants can be removed, meaning that your characters can speed up the growth rate of crops and keep them growing in all seasons of the year. However, gas and liquid transfer rates (through the stomata and the roots, respectively) do impose a natural limit on how quickly the plants can undergo their redox reactions, so they can't instantly grow to maturity, but they will most definitely form a faster and more stable source of food, which would allow your characters to form a powerful agricultural economy for the times. [Answer] Stone age means all the tribes around you still use stone tools. With your redox ability you can reduce metal oxides to native metals. One among the others: take those yellow looking stones which your descendant will call limonite and turn them to iron. Now you can produce and sell metallic objects: swords, axes, arrows, knives, spades... just be sure to sell to every tribe, so that they maintain a sort of balance of power (you don't want a single strong side to emerge and see you as a threat to their ruling and therefore attempt to get rid of your power). Whenever someone tries to trick you or to overthrow the balance you created, you can "magically" oxidize their metal back, just to make clear who is in charge. ]
[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/112191/edit). Closed 5 years ago. [Improve this question](/posts/112191/edit) In my world my races (Humans, Elves and Dwarves mainly) are almost intelligently designed (not quite created by a god in their image, but definitely 'created'). And this got me to thinking, are there any major defects in a human that you would expect not to exist if someone (or something) sat down to create the perfect humanoid? The one that comes to mind for me is the crossing of our wind pipe with our digestive system, but while I know that is the reason why we can choke I'm not sure it's 100% a bad thing as I assume it also allows us to breath through our mouths (which presumably can be beneficial). **So the question is, are there any obvious ways to improve the basic humanoid body plan?** By improve I mean it should make some aspect of our bodies work better or remove a flaw (like the windpipe cross over mentioned above). The changes should also leave a human looking human (so adding wings or extra limbs isn't an improvement). They should make sense and be feasible (so you can't just add a back up brain or heart if there is no way the body could sustain them). [Answer] ## Don't bother fixing things that will make no difference for 99% of pop Many of the previous answers are trying to remove stuff that are not useful. But, they are not really annoying either. **I was never bothered by my caecum, were you?** So if you remove it, you may save some small amount of energy/trouble for the body. But you could also later discover that, in the end, it had some purpose. Above all, you did something that will not make a noticeable difference in most of the cases. Mostly they are things that are not optimal, but their correction will not make the human more able for anything. **Do you think your life quality would increase significantly if we fix the path of your laryngeal nerve?** ## So what are the major defects in our bodies? Well, it's what **kills us**. Let’s take the most frequent mortality causes ([in Europe](http://ec.europa.eu/eurostat/statistics-explained/index.php/Causes_of_death_statistics)): * Heart diseases * Cerebrovascular diseases * Cancer (especially respiratory system) So, if you could enhance humans, increase their resistance to these problems. For instance: * Stronger heart, maybe duplicated, or able to heal better * More resistant veins (especially in the brain) * Some mechanism that can clean the veins from cholesterol and other deposits * Immune system able to fight cancer * Make an immune system that would accept transplants more easily * And so on… I guess it is less spectacular than removing wise teeth, but **waaay** more useful. Last idea: remove addictions from humans. They will live longer and better. Tobacco, alcool, games, sugar, money, … Let them enjoy it, but don’t make them need it. [Answer] ## Low hanging fruit There are several [glaring design errors](https://en.wikipedia.org/wiki/Argument_from_poor_design), or "low hanging fruit", to use a bit of managementese, in human anatomy and physiology, which could be immediately corrected by an intelligent designer with minimal side effects. For example: * Move the photosensitive cells to the correct side of the retina -- for those readers who know about digital photocameras, our retinas work like old-school photographic sensors instead of more modern [back illuminated](https://en.wikipedia.org/wiki/Back-illuminated_sensor) sensors. * Straighten out the path of the [recurrent laryngeal nerve](https://en.wikipedia.org/wiki/Recurrent_laryngeal_nerve); at present it follows a bizarre path which made sense in fish but is totally unsuitable for mammals. * Repair our defective mechanism for producing vitamin C, and in general reduce (or even eliminate) the number of [essential amino acids](https://en.wikipedia.org/wiki/Essential_amino_acid). * Simplify the anatomy of our feet; as it is, our feet have the same structure as our hands, which made sense for quadrumanual monkeys but is overcomplicated for bipedal humans. * Fix the stupid way that the breathing reflex is triggered; as it is, breathing is triggered not by a lack of oxygen but by an accumulation of carbon dioxide, with the result that we can pass out due to hypoxia without noticing anything amiss. * Reduce the number of teeth; we have the same number of teeth as the other apes, but they have elongated muzzles whereas our tiny jaws lead to severe overcrowding. [Answer] Look into childbirth. It is a very risky process. Any proper design would not risk both the mother and child during the reproductive stage. A really simple (to describe) change could be to have your fantasy races be egg layers. Egg laying is less risky because of the size/shape consistency of the egg compared to a live birth. There's an interesting fluff piece here [On Animal Births](http://www.slate.com/articles/health_and_science/explainer/2012/09/animals_giving_birth_dolphins_bear_newborns_easily_but_hyenas_risk_death_.html). A lot of lower risk birthing comes down to adult/offspring size ratios. Seahorses move the eggs to the father. I don't know a huge amount of the detail, but possibly "birth" is easier for the male as they eggs are in a more "external" area. Many types of fish lay unfertilised eggs, which a male adds sperm to outside of a female. This means there's no risk to the parents, although the offspring are subject to predation unless looked after. [Answer] There are lots of ways humans are obviously not "intelligently designed". A such designed humanoid would, for example: 1. Not have the genitals hanging outside the body 2. Have a much better arrangement of organs/spine. We obviously came from walking on all fours in an earlier form and the curved spine was there as a way to support the weight of hanging organs. Now most of us end up with back issues at some point. 3. No unnecessary organs (appendix) 4. No strange pathways for nerves (recurrent laryngeal nerve) 5. A bigger pelvis for the childbirth issue 6. The eyes could do with a redesign, amazing as they are. Possibly remove the blindspot and maybe increase the visible spectrum available outside RGB. Other minor possibilities. Many non-human animals can safely eat things that would kill us...fix that! Birds can eat hot chillis with no irritation. [Answer] The concept of designing a single new species to be outright better than humans needs an understanding of what humans are bad at... but all the things we are bad at have benefits in other areas. so if we were designing a species, then it would probably be for the express purpose of of filling a role that humans are less suited for. humans are not very strong on average, but can be, the problem comes from frequently very strong people have less ability to finely turn their strength, if a Brain surgeon puts a a couple grams more pressure on the scalpel they could cut something important underneath the bit they're working on and kill someone, a body builder can exert a force much much larger than an average human, but often finds it harder to judge the difference between 2 and 4 grams of weight pushing against a knife. both sides have benefits and both have drawbacks, but not in their chosen environments. It would drastically depend on what you were designing them for, imagine a world like that of Blade Runner (original as well as sequel) but in this world they are genetically engineered humans rather than synthetic ones there would need to be a purpose to them, if you wanted ones that worked all day every day within a coal mine, you'd probably want better ability to filter particles out of the air they breath, similar to the way the nose does but on a faster scale, and they would need to be stronger, and therefore a stronger heart to deal with the stronger muscles, but would they need to be intelligent? probably not, otherwise they might start to question "why am i doing this instead of the regular humans." On the flip side if you wanted to design the perfect Doctor or brain surgeon (that may or may not one day be in a car crash and become a wizard...) then strength loses out to very fine and precise motor control and high intelligence, but maybe an increased immune system to deal with being around sick people all the time. Humans are prone to genetic change, height size shape and characteristics can change significantly every generation, this is what allowed humans to evolve the way they have, but this also makes genetic disorders much more common, admittedly this tends to happen more to the male side of the species then the female, as is more common in the entire animal kingdom. if you where designing a new species of human specifically to work in and around Radioactive areas, you would probably make the chance of a genetic mutation a lot lower, this would drastically reduce the risk of Cancers and other serious health risks. [Answer] I will address your initial question: * *... are there any major defects in a human that you would expect not to exist if someone (or something) sat down to create the perfect humanoid?* But let's formulate it in a bit different way: * *Would we expect to be able to distinguish between designed and evolved life forms?* Yes, but not necessarily. A thing which may distinguish designed lifeform from evolved life form is that the first one is bound by the realm of physics, chemistry and other processes affecting or theories describing ontogenesis of the life form. Naturally evolved life form is not only bound to all mentioned above, but also by inheritance of previous life forms and their particular restrictions and environmental factors which did shape them(their ancestors) in the evolution process before it split to another branch which is a root for the life from we may investigate. In that regard evolved life form is more constrained in choosing or refurbishing its inheritance and has history, the history behind each element of its existence. The designed life form is more free in that regard, creators more free to implement different solutions as they are not bound by the necessity of one solution to transit in another solution they may choose solutions from all possible solutions and not care if such thing could evolve naturally, are there some problems in that evolving, is there problem in transiting from one state to another. In that regard flame throwing dragons most likely to be engineered solution. There are tricks to implement, creative solutions to create a system in the way and fashion evolutions won't work. To ignite a flame - is it possible to use electricity, sure, piezo elements, sure it possible. will it emerge naturally? Not likely - each change in natural selection should be useful or neutral, or at least not that bad. But better are those which get something for the change. It may be more difficult to detect the creation if creators are copycats. The life from they created may look natural, as it has pieces of the puzzle which may have recognizable historical meaning. But also we should then take look at the whole ecosystem they exist in. The first question would be to ask if they are part of it and its historical evolution records. Then to see if their historical records belong to certain branch or multiple branches. Analyzing that data we can essentially tell if they are the probable result of the evolution of the ecosystem. Less probability, with a good understanding of the whole system and processes, higher are chances of their artificial creation. As for specifics of improvements, it is a broad question and is opinion based part of it. Not all improvements are good in all environments, and they come with the cost of losing some options, because of fundamental limitations of blocks which are used. As an example - fur is good for the cold environment, but excessive one is limiting mobility in a hot climate. There are incompatible solutions, and more adaptations we may willing to have, higher chances to hit the wall of those incompatibilities. We may expect a wider spectrum of parameters of environment they can live in - but it is not granted. And intelligent design may find different solutions around incompatible adaptations and each such trick decreases the probability to evolve naturally, so in a statistical sense, they can be well above average in the system, so we could suspect they are designed or it was a result of a unique situation. Taking into the account other data, we can say more precisely. Things can be simple as everyone has blue eye's and 10-100 variations of the genes encoding that, depends how long in the past was the last correction. very thing connection of certain aspects, as an example - not the blue eye, then died in a week or even born dead - it can be a sign of highly packed code, it can be a sign of design. Because naturally evolved life is more acceptable to mutations, more wiggle room for that, as it is a driving force for changes in their development and they are used to that. So very high mortality rate among mutants and very rare mutations can be a sign. They may look as a diverse system, but it may be static in the diversity and may have a higher mortality rate in newborns than usually average in the ecosystem system. So there are ways to detect tampering or creation. They aren't guaranteed. Hardest would be a good creation of a whole system from scratch trying to mask the fact of creation. A system probably can be created to be indistinguishable from a naturally evolved system. But we can test and try to determine how is the probability of the system to evolve naturally - there can be a difference in probabilities on the average in the galaxy, but we would not be able to catch the hand, just have a probability as a result. as for improvement - add them more intelligence, the thing is not that much required for survivial, so hard to get too much of it in a natural way ... [Answer] In our bodies of evolved creatures we have the so called [vestigial organs or functions](https://en.wikipedia.org/wiki/Vestigiality), which are leftovers of previous features which we abandoned during the evolutionary path. Some of these organs or functions are: * The human caecum is vestigial, as often is the case in omnivores, being reduced to a single chamber receiving the content of the ileum into the colon. * The plica semilunaris on the inside corner of the eye * The formation of goose bumps in humans under stress is a vestigial reflex: its function in human ancestors was to raise the body's hair, making the ancestor appear larger and scaring off predators With an analogy, you could compare them to a car having leftovers of the horse attaching bars used in the chariots from which it evolved. In a properly designed system (and I assume an intelligent designed species is such), no leftovers should be present. [Answer] Well, to answer that question, we will have to use our imagination a little. So, let's pretend that humans created a "new type" of human being. An improved human. How would this human look like? But would they work in a fantasy world? No. If you use a thing from science fiction on a fantasy world, it will probably not work out. So, what could you do to "improve" the human body? To create an "improved" human body, we will not only need to compare them to normal humans, but to mythical creatures too. But, if you think about it, what would you change? It's not like we are perfect, but I think that if something needs to be changed it would be almost completely aesthetic. I think that if you want to change something about the human body in your fantasy world, you are the only person that can really decide. [Answer] Intelligent design - no mouth. Mouth are not needed as food is digested through osmosis or photosynthesise (both ways working at once). You also don't need it for breathing as breathing through skin with ability of having gills-like skin. No speaking needed as telepathy would be a thing (something like Morse code by eyes but actually by changing your electro field). Also give the possibility to digest everything. Toadstool? No problem. No energetic value apart from that muscarine but that won't affect you. why brain in skull? Keep much better eyes (like four of them) on a pole so they can see far and wide but keep brain in some extra cushion. Better even split brain functions and place their respective centers in different places in body. WITH extra replacement. So when one part of "brain" is destroyed it don't affect whole. Regrown lost limbs. Like this is the worst. You're walking and suddenly elephant stomp on your foot. Man! So not cool. But you can easily cut it off as it will grow back in few weeks. You just need to osmosis some more energy and minerals. ]
[Question] [ My character kills a goat in the mountains and eats some of it for dinner. What kind of plant or mineral could he use to preserve the meat to carry with him so that it stays fresh and doesn't become contaminated? What kind of process would he use? He can only use things that could grow in rocky mountainous areas or something that he brought with him for that purpose. His only other "tools" are a knife and fire. Is there any basis to believe that preserving meat in this circumstance is even possible? [Answer] The most obvious solution is [salting or brining the meat](http://www.offthegridnews.com/food/preserving-meat-without-refrigeration/). This requires your adverturer haul salt around, which is a rock, so it's a bit heavy — depending on how long he needs to do this. A pound of salt will cure at least 48 pounds of meat. However, [this site](http://sciencenordic.com/herbs-and-berries-can-preserve-meat) reports that the following herbs and berries can be used to cure meat: aronia (chokeberry), horseradish, ramson, red currant, savoury, sage, sloe and cranberry. This is actually a really cool idea for your story as few people would know this could be done. [Answer] Your character could smoke the meat and/or dry the meat. From [Wikipedia](https://en.m.wikipedia.org/wiki/Smoked_meat): > > Smoked meat is a method of preparing red meat (and fish) which > originates in prehistory. Its purpose is to preserve these > protein-rich foods, which would otherwise spoil quickly, for long > periods. There are two mechanisms for this preservation: dehydration > and the antibacterial properties of phenols and other chemicals in the > absorbed smoke. In modern days, the enhanced flavor of smoked foods > makes them a delicacy in many cultures. > > > The only "plant" needed here would be wood as fuel for the fire. Given that the tops of mountains are 1) windy and 2) cold, they are good places to dry meat. I remember from an episode of *Good Eats* by Alton Brown that the Andes did a good job of dehydrating meat. --- [Answer] I lived off-grid for around 15 yrs in a 4 season province. I shot deer, killed my pigs & chickens, rabbits & game birds which I snared. For the deer, it was stored in large buckets with salt peter added to the water. (military used to put it into food to keep men from fornicating with each other) You soon get sick of the flavour, but soaking the meat in lots of garlic & wine will remove a lot of it before you BarBQ it. One of the types of bacon we used to make in Hungary is cured in salt, lots of cloves or garlic & ground sweet paprika rubbed ontop. This is bacon that has no streaks of lean meat in it. Look in old cookbooks. It is one of the 3 types of amazing bacon we make. Ground meat with very specific amounts of salt, paprika, & a few other spices make La'ngold Kolba'sz & you hang it over broom handles in a root cellar temp space & slowly all the fat drips out & the sausage shrinks, dries & becomes similar to peperoni but WAY better. Better than jerky but same idea...slow drying at constant temps. If you boil meat that is mostly bony, like pork hocks etc, then place the hand sized pcs into bowls, then pour that water over the meat, put in a cool place, the broth will become hard aspic which will keep the meat a bit longer than otherwise...again bit of salt, garlic & paprika cooked into the water is the flavouring. Then removed. Both spices small in size but big in flavour!!! If you want to keep fish, you must keep a clean cloth ontop of the bucket of water that they are submerged into & each day remove the fat that comes out of the fish & wash out that cloth or it will go rancid. Or salt & dry like people in NL & Labrador did. You have probably seen small wide mouthed bottles of fish in the supermarket not far from Saur Kraut. If you 'can' meat or low acid veg. in mason jars you have to do them in a pressure canner not just a regular canner because those DO NOT get hot enough completely thru to the very center of the food itself. Remember that food born poisons are invisible, unlike a bit of mold on jam or a glass of chillie that explodes. Read Keeping The Harvest, once sold thru Harrowsmith. Storing vegetables in sand, or wrapped in paper or wood chips still works. I still live without a fridge cus I prefer to buy real estate than make companies wealthy. I store food in large containers with egg cartons etc below & above stuff which is out of plastic, wrapped in T-towels or papers. All veg & fruit need to gas-off their moisture but not completely. Deep holes are nice and cool. Way up high in evergreen trees also...and protect food from rodents except maybe squirls. [Answer] Simplest: Air-dry the meat. Just cut it very into thin strips (if you need to move the next day) or better into tongue-sized fillets, if you can sit there for 4 days. Speed it up using smoke from your fire. Keep bugs off the meat and prevent spoilage by lightly coating it in wood ashes before hanging to dry. Also improves the taste, if you use the right wood for your ash. If the goat was smallish, and there is only one or two meals left: Just butcher the goat and stuff the meat into its own stomach. Easy to carry, and keeps the meat cool and sanitary for about 2 days, tops. *meat* does not spoil so very quickly. Blood does. [Answer] **Freezing** The mineral is water, or rather snow. Your adventurer is in the mountains. He can preserve his meat by climbing into the colder regions and burying it in snow. He could build up a considerable cache in this way. [People who have died climbing Everest](https://en.wikipedia.org/wiki/List_of_people_who_died_climbing_Mount_Everest) are still to be seen, their bodies perfectly preserved in snow and ice. Also of course there have been finds of much older bodies being preserved in the snow. --- > > [THE MUMMY OF an ancient Inca girl](https://www.nationalgeographic.com/science/article/news-inca-argentina-la-doncella-sacrifice-archaeology) sits literally frozen in sleep at a > museum in Argentina. > > > The mummy, called La Doncella or The Maiden, is that of a teenage girl > who died more than 500 years ago in a ritual sacrifice in the Andes > Mountains. > > > [Answer] Tuna cans are cooked after being sealed, so no bacteria gets to the inside after cooking is done. The meat will last for years, but still not forever. Our character may use a re-usable metallic jar with a screw-on cap to seal food and cook it while jar is sealed. ]
[Question] [ I'm looking for a weapon a ship can carry that can disable a ship without any permanent damage to its subsystems or significant hull breaches. This will mostly be used by pirate factions (capturing a ship to hijack and/or loot) and law enforcement (retrieving stolen ships and capturing fugitives alive, etc.) I don't believe EMP is a viable option due to its ability to permanently damage electronics. This is meant to be a highly specialized weapon for people who want the ship and/or its crew/cargo intact for boarding. Often times the ship needs to be able to fly away after being captured. I had one thought of a weapon that forcefully shuts down the main fusion reactor of a vessel by one of two methods: * Disrupting a continuing fusion reaction by denying one of the conditions required to sustain it. * Introducing elements that would cause containment to fail and forcing an emergency shutdown, either automatic or done by those aboard. The goal of either method is to force the reactor to power down and have to 'cold start' off auxiliary/reserve power, which would take time. By that time, boarding parties would be on the ship. Is there anything that already exists (even theoretically) that could potentially bypass all of the armor, electromagnetism and thermal/radiation shielding of a fusion reactor and introduce conditions that would shut it down? [Answer] A [muon](https://en.wikipedia.org/wiki/Muon) beam. It will pass through matter until it loses enough energy. Then it deposits an electron and a lot of energy. Let’s suppose the muons are tuned to directly interfere with the power system (e.g. acting as a [catalyst in fusion](https://en.wikipedia.org/wiki/Muon-catalyzed_fusion)). Safety systems will detect excursions that are not controlled as expected, and shut it down. As a bonus side effect, the penetrating negative charges also introduce errors in their computers, flipping bits and trashing memory but not destroying the chips (or whatever they are). [Answer] # Remote hacking Depending on the technology standards of your universe, it might be worth considering the applications of **remote hacking.** Given that you want to leave as many of the ship's systems and components intact while simultaneously depriving the inhabitants of access, it would make a lot of sense to target the authority over those systems, which would almost certainly be some kind of computer. With a high-powered wireless transmitter and sufficient algorithms, it would be quite plausible to apply existing attack methods (DDoSing comes to mind). [Answer] Have you tried a weapon that was designed to raise the heat of the space ship? Vaccumes are notoriously good insilants and cooling is a space ship was always a harder problem for NASA than heating it. Perhaps a laser beam that doesn't do any hull damage, but will cook the ship... if your pirates are keen on taking the ship's space wenches, you don't even have to smoke them out. Just keep the heat on the ship (literally) and rely on the ship's safeties and power routing systems to cool units rather than defense of the ship or engine power (both of which will cause the ship to heat up under natural use). It could even put the computer into an emergency state... essentially the space ship equivelent of leaving your iPhone in your car during a summer heat wave... at a certain temperature, the phone will disable everything save for Emergency calling. Once the ship cools off most systems should be intact, unless you have an intrepid smuggler who is most definately bypassing safeties to get away from you. Might even be better to have somekind of attached device as the laser can be beaten by staying out of the firing arc. If your hero is the victim of said pirates, they could even try to rely on his ship outlasting yours (a laser device generating heat in enough qualities to overwelm an enemy ship is probably going to put your own ship into a redzone). [Answer] I don't know of a way to remotely shut the reactor down, but you could force the crew to do it. One long distance method would be through warming the spacecraft up. Currently, your spacecraft has this fusion reactor, which is igniting propellant and pushing the spacecraft along. But there's also waste heat, so your ship has these great big radiators which get rid of waste heat by converting it to infrared. Unbalance that system, and your spacecraft overheats. So, your space pirates could shine something like an infrared laser at their target, and let it slowly overheat. It wouldn't have to be focused well, so it could be at a great distance. The hull would get warm, and radiators facing the pirates, instead of rejecting waste heat, would be accepting heat, so the system would be thrown out of equilibrium and the spacecraft would overheat. Once their victims beg for mercy and do whatever the pirates demand (shut down the reactor, like you said, or maybe give remote access to their computers), our pirates would probably have to assist in cooling down their victim's spacecraft. Maybe they have attachable cooling systems built specifically for this purpose. [Answer] I don't know much about your ships like if they have FTL drive, shield, lasers, sub-light speed, etc but I'll try to make "universal" answers. # Remote Hacking If you don't want to damage the ship you could try to hack them, ships has comunication sytems so you could try entering to their system by the comunication console. In Battlestar Galactica cylons used to hack humans ships to destroy them. If a remote hacking by comunication console seems impossible you could make a little dron, this dron fly to the enemy ship, attach to their armor, search for a console or data cables, connect to them and start hacking. By radio or Wi-fi you comunicate to the dron and the dron hack the ship. If you want be able to support the hacking you simply need a better firewall or programmer. Also you can do like in the series, in Galactica the main ship (I forget the name) used cables to connect the sub-networks of the ship and when they was under a hacking attack they simply unplug the network cable. # Electromagnetic Countermeasures Ultra powerful magnetics turrent can "fire" an electromagnetic wave. You can use two ways to desactivate enemy ship: * **Increase "slowly" (in 10 seconds) the power:** You can make an annoying electromagnetic wave, harmless to electronic circuits but it increase his power all the time. The enemy ship would have to desactivate the circuits in order to not destroy them when the magnetic field become too powerful. Surrender or EMP. * **Have an "electromagnetic shower":** making a big and powerful EM wave you can "blind" the target, EM distrub communications, radar and even targeting systems, the ship would be incomunicate and blind. ¿Would you enter into the hyperspace or a wormhole blind? * A third way could be increasing the static energy of the ship by gamma ray, if the static is to high it will break technology and even kill the crew (in space static is a real danger). The only problem is that I see that in a sci-fi series and I don't know if that is possible. Also, if you think that a EM turrent is too powerful or strange you can insted have mini drones that fly around the enemy ship and make the EM field. # Dron Brake Ally ship (a big one) could launch hundreds of little drons, they attach to the enemy armor (by steel ropes or hooks) an fly to the opposite side. A lot of them would stop the ship, the problem is that you need a lot of them and they have low fuel storage also. # Ship Roop Tying If you don't like drons you can have a lots of steel ropes launchers. They launch the ropes to the enemy and them attach to the ship, then your allies ships stops the enemy with they own thrusters. # Destroy the Thrusters If enemy ship has ion-thrusters, EM thrusters, gravitional drives or something like that you can shoot to their thrusters, I don't think they will blow up, right? # Heat Laser By a laser or microwaves you can heat enemy ships (in space ships doesn't cold down so easy). If the ship reach to a critical temperature the fussion reactor would turn off to avoid explode. Also people can die "cooked" or by deshidration. [Answer] A big glove on a spring. I know that spacey-fusion-flying-things are the pinnacles of technology. So is Tesla cars. Take a look at what it take to ground one. A circle made of chalk around it. Or a dent that disrupt the sensor reading. It can be run probably in some "service mode" for a short time or with a low speed but if you would like to use it normally "the computer would say NO". We all think about spaceships from movies, with force fields and Skywalker-like pilots. But we have space-stations and ships colonizing other planets. And they don't have magic bubbles around them. So it would take just some small space debris hitting the right spot. Think again about car. Everything is inside it, the fuel tank, the engine, cables. BUT the fuel lines are outside. So it would take a car that is just a bit to low, going a tad to fast over a speed bump that could result in lowering the fuel flow to engine. Hell, last month I was driving behind a girl that had broken return line. [Answer] **A flashbang for spaceships** When we want to disable people without hurting them, one of the things we do is throw a device near them which briefly overwhelms their sensory inputs. The same principle works for electronics. In fact, if you shine a bright IR or UV light at many electric cameras, you'll blind them. In cases of extreme sensory overload, the damage can be permanent (for both electric devices and organic sensory organs) and require the sensory hardware be replaced. This can be extended to spaceships. Imagine several devices ejected from an attacking ship which deploy themselves around a target ship. They can blast a ship with various bandwidths of radio and optical light to overwhelm their radar, optical cameras, etc. And a blind ship is effectively an incapacitated ship, unless it's capable of out running its attacker or the disruptive devices. If you can permanently blind a ship, that's not necessarily a big problem since its ostensibly easy enough to fix if only the detectors need replacing and if those detectors aren't incredibly integrated with the rest of the ship hardware. And even if this fairly easy fix is too complicated to pull of as a field repair, the attacker ship could guide the target ship home after seizing it. That said, I have a hard time imagining a futuristic spaceship being permanently blinded so easily. While blinding devices may be able to do some damage to the detectors, these are detectors which need to operate during some pretty rough solar weather. It's possible that the blinding effect may only last while the devices are operational and properly deployed. This is workable too because it would provide a weakness for the blinding technology. Whichever route you go, I think there are workable story elements. **Side note:** > > I had one thought of a weapon that forcefully shuts down the main fusion reactor of a vessel > > > Oh, god. This sounds terrifying. * While its conceivable you can figure out a way to do something to a ship's reactor that forces the crew to shut it down, that implies something bad will happen if they don't. Otherwise, why would they be "forced" to shut it down? So, what happens if they don't shut it down in time? * Finding a way to disrupt a reactor and trigger an uncontrolled shutdown doesn't sound any better. It actually sounds worse. This kind of technology requires special and careful choreography. Disrupting a fusion reactor sounds like you're turning it into a bomb. TL;DR: Don't hurt the reactor. Don't touch the reactor. In fact, don't even look at the reactor. [Answer] # "Intelligent" mesh You launch a large projectile towards the enemy ship (you need to have already almost matched velocities). The projectile will unfold into a very large, conductive net that is able to enmesh the whole of the enemy ship, covering sensors and disrupting communications. Several launched meshes could cooperate, and preventing a mesh from engulfing your ship, while possible, would be tricky and/or require EVAing outside of the hull armor's protection, or specialized hardware that law-abiding spacemen might not have handy. For whatever reason, flying blind is not a good idea. The mesh could also be capable of hacking the enemy ship once it has achieved contact, or could blind it to a subsequent boarding. [Answer] Existing answers are pretty thorough. Here is one more that is a little more outre. Reference: this excellent "crushed between two portals" video (the soundtrack makes it). <https://www.youtube.com/watch?v=0TZd95BCKMY&t=81s> If you have the right kind of FTL tech you could catch the ship in a pocket dimension - travel takes it through 1 portal and back out the next to remain in the same place. This maneuver can be called the @Raditz\_35 net. Once in the dimension the ship and its occupants can do as they like. If you can communicate with them, you can hold them for random and insist they power down the ship and board a shuttlecraft to be set free. [Answer] You could also go with the basics: Threat of destruction. Let the crew know you have the capability to destroy them, then kindly ask them to shut down their drives if they want to live. This should qualify as something *"that already exists that could potentially bypass all of the armor, electromagnetism and thermal/radiation shielding of a fusion reactor and introduce conditions that would shut it down."* This answer is pretty much the same as the remote hacking suggested in other answers, except targeted at organics instead of machines, and far easier to execute. Another option is to bribe the engineer at the dock. [Answer] Going in another direction you could also stun the crew by either disrupting their brain waves to induce a sleep like state, the brain activity of deep level four sleep is distinctly different than REM and being awake. Or if they take control of the internal communications system they could emit a sound that can stun the crew. [Answer] EMP. Despite popular belief, EMP does not "fry electronics", it simply interferes with them and rarely results in permanent damage. Cars for example might stall but can usually be restarted right away. On a spaceship that might mean that you have to restart the hand-wavium reactor thus giving the pirates enough time to swoop in and steal the ship/cargo. [Answer] The most obvious way to disable a ship is to target the crew. If you have artificial gravity, it might be possible to apply a gravitational field on the target ship. Depending on the level, you could pin the crew to the ground, make them black out or even kill them without any significant damage to the ship. [Answer] What about Sulfur Hexafluorine? Instead of disrupting the fusion reaction itself, why not stop its electrical output. Alot of the space ship designs have the fusion reactor or power generator connected to the power systems of the ship through an almost arc system, shown by that wonderful dancing or condensed lightning somewhere in the ship. I would theorise that it was done like this to reduce electrical backdraft towards the reactor. Sulfur Hexafluorine is inert and inhibits electric arcing. Such as duncking a tazer into this will stop the arcing of electricity through the air. So if you could introduce Sulfur Hexafluorine into 'arc' chamber, the power systems will turn off. To reintroduce power, just extract all the gas from the chamber and let it fill back normally and the system will spark again. Theoritically with no damage to the ship. This is essentially the same a pulling the plug out, then plugging it back in again. The only difficulty would be in introducing the gas into the chamber, whether you use: * Teleportation of a container of the gas to the right place, or even just the gas itself, * A robot drone of some sort to infiltrate the reaction chamber, * Hack the systems to release it, (this assumes that Sulfur Hexaflourine gas is already in place as a failsafe system). * Crew member infiltrate the ship and release the gas manually, * etc etc. The best part is that those that wish to escape capture will have to come up with defenses while the attackers infilrators would have to be more clever to defeat said defenses. To note as well, at least the life support systems will have a back up power source at least so the crew on board the disabled vessel will be fine, otherwise as soon as their shields go down, a mass teleportation of all crew into the hold/brig or just teleport them about 10 metres outside their own ship. Another method is to just drug the whole crew with a release of gas but that is too easily preventable. [Answer] If you've got good spies, discover the enemy ship's "combination code", like the Enterprise did to the Reliant in *Wrath of Khan*. <https://scifi.stackexchange.com/a/131703/73693> > > SPOCK: Reliant's prefix number is one six three zero nine. > > SAAVIK: I don't understand. > > KIRK: You have to learn why things work on a starship. > > SPOCK: Each ship has its combination code. > > KIRK: To prevent an enemy do what we're attempting. Using our console to order Reliant to lower her shields. > > SPOCK: Assuming he hasn't changed the combination. He's quite intelligent. > > > Then shut down everything (except the fusion reactor!) and lock out the locals from getting back in. [Answer] Just take a page out of Star Wars. Use gravity well generators to immobilize the enemy ship. Create a gravitational field so strong that the ships cannot move even at full throttle, and any weapons fired would rebound immediately. Since the gravity well is created in a uniform bubble around the enemy, the ship will be in no danger of being torn apart. [Answer] Spaceships are less like nautical ships and more like bullets, specifically a bullet that can change direction, that can see you from multiple solar systems away, is actively trying to avoid you and last but not least has enough firepower to rival a 21st century superpower. Suffice to say you need to ambush them. There's two kinds of ambushes, you can either anticipate their path and "lie in wait" along that path, only to watch helplessly as they zip by at astronomical speeds, or set a baited trap. A distress signal/beacon is the bait and the seemingly abandoned spaceship or station is the trap, you want them to send some of their crew to investigate the ship/station then somehow use those investigators to gain a foothold aboard their ship. For example you have someone very skilled covertly abduct one one the investigators aboard the ship/station and impersonate them, then that infiltrator either disables the target ship, kills everyone on board or steals whatever thing that's aboard that ship that you're after and escapes with it. [Answer] ARR, FELLAS! ye want a ship nice and whole, without that pesky crew getting in yer way? Fear no more, we offer ya **The Bactrion-K-74!** Arr, ye heard it right, scum: The unique, efficient way to clean up a ship and add it t'yer fleet in no time! Just launch this one, yes one plating-shredder-tipped torpedo into the ship, let the nasty buggers in its head to kill *everyone* aboard, then don yer suits and go clean up! Yeah, a little of sweat in return for a prized premium, that is the wonder of **The bactrion-K-74**, your bioweapon of choice! Antigens included in the price to protet yer crew. **The Bactrion-K-74!** Because we care for ya! [Answer] Option #1: Hacking Probably the safest and least invasive option that allows you to turn subsystems on the target ship on or off at will. Option #2: Carefully crafted EM interference Target control subsystems with just enough EM interference to cause them to "glitch out" in a reboot loop, without causing permanent damage or frying them completely. Option #3: Thermal shutdown If you have a weapon that causes overheating, aim it at power generation systems or engines, forcing them to throttle back or temporarily shut down. ]
[Question] [ Mountain goats, and some other mammals, are exceptional climbers. They can climb slopes at greater than 60 degrees. Unfortunately they are too weak to carry humans or goods without serious injury risk. This lead me to wonder, is it possible that a beast sturdy enough to bear a human could be mountain dwelling and climb slopes of >60 degrees or is there a limit based on weight, size, shape or muscle that means a beast strong enough to carry a human could not climb these slopes? [Answer] I think you want to move away from goats and look at monkeys. Monkeys and even the great apes carry their young on their stomach or their back. They can still climb, sloths do too btw. And [Giant Sloths](https://en.wikipedia.org/wiki/Ground_sloth) existed. They weren't tree dwellers but they could be changed into climbing mountains. As John mentions in his answer, climbers without claws or hands rely on their center of mass to retain balance. Adding a moving rider to that is a recipe for disaster. So hooved animals are a poor choice here. [Answer] Your big problem is if you start adding and taking away weight from a climber you throw off its balance, a rider will drastically shift their center of gravity and widens the animal, making steeper slopes much more difficult. breeding for size is not an issue, but drastically shifting the center of gravity and widening the animal is, especially for a goat like climber. put 50 degrees as your max and you will have much more success. [Answer] A [takin](https://en.wikipedia.org/wiki/Takin) might be able to do it. [![enter image description here](https://i.stack.imgur.com/tosP5.jpg)](https://i.stack.imgur.com/tosP5.jpg) [![enter image description here](https://i.stack.imgur.com/AidXM.jpg)](https://i.stack.imgur.com/AidXM.jpg) from <https://www.youtube.com/watch?v=q1VR9OMDdek> Takins are sturdily built. Males takins can weigh 600-700 lbs and are 4 feet at the shoulder, which is comparable to a horse. They live in mountains and can negotiate steep slopes. I think a rider who does not want both of them to pitch over backwards when going up a steep hill could switch and ride underneath the takin, Odysseus style. from <https://thejosiasdotcom.files.wordpress.com/2017/04/odysseusram2.jpg?w=680> [![enter image description here](https://i.stack.imgur.com/8mtdv.jpg)](https://i.stack.imgur.com/8mtdv.jpg) The existence of the song "Takin a ride" from the soundtrack of the movie Heavy Metal has defeated my efforts to search for instances of people actually riding takins. [Answer] You might be surprised at how steep a grade a horse & rider can climb. I've ridden up & down slopes pretty close to 45 degrees myself, and I'm far from an expert. Part of the trick is shifting your weight to keep the horse in balance. You don't just sit in the saddle: in even a moderate climb, you shift your weight to balance over the front legs. On a steep grade, you can be almost lying along the horse's neck. On descents, just the opposite: you lean back to keep the weight on the horse's back legs. For examples, do an image search on e.g. "Tevis Cup Cougar Rock", and you'll find plenty of pictures like these: <https://mfthba.com/wp-content/uploads/2014/11/cougar-rock-300x212.jpg> <http://www.horsesinthemorning.com/wp-content/uploads/2015/07/Karen-Chaton-Bo_Cougar_Rock_2013-1024x820.jpg> The real problem (other than keeping your saddle from slipping) is the footing. Just as with humans, loose footing can make a slope difficult or impossible, not to mention dangerous for horse & rider. I think, from the few times I've seen mountain goats in action, that they are not actually climbing a slope, but going from one small level ledge to the next. [Answer] As a general rule, mountain climbing mammals tend to be small, the largest being goats, donkeys, and bighorn sheep. They live in the mountains because they have found a niche with an unused food source, and no predators. Anything larger either has to be a roaming herbivore that may not find the forage it needs to thrive on mountain sides, or a carnivore. The problems of trying to ambush prey with little concealement and carrying it off, all without falling off the mountain yourself, preclude large carnivores from being mountain dwellers. [Answer] I’m pretty sure what you are searching for is a Yak. They can carry heavy loads and even people and are very good in steep and uneven terrains. You see them all over the Himalaya mountains. ]
[Question] [ With the advent of Legion on World of Warcraft, a iconic weapon from the series came back to the mind of gamers all around the world - the fabled *Warglaives.* [![Warglaive Model](https://i.stack.imgur.com/AqwfK.jpg)](https://i.stack.imgur.com/AqwfK.jpg) Those weapons appear in several games, sometimes using other names or with some minor design changes. Below is a similar weapon, the *Faeblade*, from Kingdoms of Amalur, which illustrates how those are supposed to be held. [![Faeblades](https://i.stack.imgur.com/GLP8m.jpg)](https://i.stack.imgur.com/GLP8m.jpg) More often than not, they are the coolest thing you have the chance of putting your hands on. They are swift, fast, agile blades that deal a lot of damage using all sorts of acrobatic strikes. However, warglaives are a strange type of weapon. They have two massive, curved blades on each side of the hilt. The outer side of the blade has a cutting edge that is used to perform slashing attacks, and the two points can be used for quick stabs. They are also used in pairs, with one of those double blades in each hand for mayhem. At least in theory. I started to craft a pair of wooden warglaives for a friend's demon hunter cosplay, and while building them several problems showed up in the design. * You are supposed to hold them by the middle part with just one hand, holding them on a horizontal plane in relation to your body. Holding them that way creates a lot of pressure on the arm and on the shoulder. * They are huge. each blade is supposed to have the same length as one of your arms so, when you hold them on a horizontal plane in front of you, they use almost the same space that you would use with your arms open, spread to the sides of your body. This makes swinging them with any semblance of precision hard. Like, real hard. * They are *Heavy*. The draft I'm making is just plain wood, but a real warglaive would have metal blades. I can't imagine this being anywhere near usable if they were made of steel. Combine this with the fact that you are supposed to use them with just one hand, and you have a way bigger problem. * Warglaives are finicky. Since they are so heavy and so big, once you gain any sort of momentum with them *you are not stopping anymore*, unless you let the blade go. Try to do a horizontal slash, and you end up spinning around like a oversized fidget spinner. Still, I really want to make them usable on my sci-fantasy setting in a more realistic way, and maybe even craft a realistic pair of those for a more sci-fi cosplay. I know that, as designed originally on those games, warglaives would suck. Like, really suck. However, we are the *Worldbuilding* community, and making sucky things work is one of the things we do best. With that said, I enlist your help: **Without resorting to magic and using modern manufactory materials and techniques, how one could make usable Warglaives? Keep in mind they are supposed to be used in pairs!** [Answer] Wanna keep as much of your blade as possible while still being practical and dual wield-able? Apply the glaive's design to **[Tonfa](https://en.wikipedia.org/wiki/Tonfa)**? The blades merge into a single blade, with the handle perpendicular to the back. The blade runs along the arm and extends past the wielder's hand. The striking range should still be the same as the glaive provides, while making them easier to carry and strike with. They're more stable to block and counterattack with than the glaive too. [Answer] When I saw this warglaive my first thought was "belt buckle". But who could hold up their pants with a belt so awesomely buckled? One too awesome even for pants: **WARLORD!** [![enter image description here](https://i.stack.imgur.com/OwAGY.jpg)](https://i.stack.imgur.com/OwAGY.jpg) On first impression you might not guess that WARLORD is too interested in the ladies. You would be wrong! And the ladies are very interested in WARLORD, especially when he wears his formidable warglaive belt buckle! [![enter image description here](https://i.stack.imgur.com/jdnoT.jpg)](https://i.stack.imgur.com/jdnoT.jpg) Careful ladies! That warglaive is sharp! Watch your eye, you! Seriously: there are many benefits of the warglaive as belt buckle. 1. Heavy warglaive is supported against gravity by belt, so strength can be used for maneuvers. Suspenders / lots of leather straps help. 2. Hands stay free for other weapons, grabbing / slapping enemy, or gesturing. 3. Skilled dancers (like WARLORD here) can use lambadaesque pelvic motions to rip, tear and thrust with the horns of the warglaive. Alternating left and right thrusts come naturally. 4. Rippling core muscles and thighs are much stronger than arms and ease the use of heavy warglaive. 5. Warglaive balanced at center of gravity allows much faster recovery after a maneuver. Also centered warglaive makes spinning, pirouette like attacks possible. I worried use in pairs would be tricky. But there is no reason the second warglaive could not also be mounted on the belt, but over the very minimally adorned rear. I will leave to the readers imagination the anatomic correctness of WARLORD modelling this rear mounted warglaive - formidable indeed but maybe a little too spicy for the stack. [Answer] ## Dual wielding You don't for several reasons. Lets go over your first issue, dual wielding identical weapons. This serves no practical purpose. You can't strike at a target twice at the same time. Your weapons would clash so you're alternating. Now the speed increase between two identical weapons and a single one is small. Both using a single weapon or using different weapons would have an advantage here. A single weapon would be lighter or could be made bigger, increasing the distance between you and the enemy weapon. Two different weapons would give you a greater flexibility. For example an axe to hook a shield and a sword to exploit the opening. Likely one of them would be used more defensively. Because that's the thing. Why would you not use a shield? only if you wear sufficient armor to negate the need for it. But then why not opt for a bigger longer weapon and engage the enemy from a greater distance? Dual wielding isn't practical. You can't aim and in melee its disadvantages outweight it's advantages. So that's your first problem with warglaives. ## Weight Now if we ignore that we get to the second problem, weight. They're indeed heavy. You're only utilizing half the weight for reach because you grip your weapon in the middle. I'm sitting here unable to recall any melee weapon that extends an arm's length in both ways. A quarterstaff wasn't wielded in the middle spinning around. Sure there was generally one hand in the middle but the other would be more towards one end. Your hands continuously shift along the shaft. Extending the weapon towards your enemy. It's held in front, strike at the enemy, swipe at his feet. So what kind of attacks could a warglaive do a sword can't? They look like a double scimitar to me. I would even argue the curved blades make using the underswing of the wrist even harder to use. It has limited mobility to begin with. As you mentioned yourself, weight means momentum. I'd say you're better off wielding sucha heavy blade like an axe. Each swing swirls into the next. You don't just start an attack, you keep them flowing. That on the other hands kida requires you to have another way to block. Something like a shield would work nicely. ## What works So not to be a total downer, what can we get to work? Modern materials allow for a great deal of light materials. Aluminium with a harder edge? I'm not a smith or metallurgist but I'm sure modern material can reduce the weight. Second thing I like is the handguard. It's basically a buckler. A small one but scale it up to the size of a dinner plate and it would serve you well. Now bucklers have been used offensively. A sharp metal rim gives it a mean punch if you strike with the edge forward. The curve even limits the contact point. Alternatively bucklers have been wielded with a [dagger gripped in the same hand](https://www.youtube.com/watch?v=EQ1q-IfLDdo). Allows for a stab if your defensive hand manages to spot an opening. [![Yes this is a targe, same technique applies here, grip is a grip](https://i.stack.imgur.com/tZfMY.jpg)](https://i.stack.imgur.com/tZfMY.jpg) ## My design Make one buckler with short blades, one going up, one going down. Alternatively go for a broad push dagger on the knuckles. Either way, knives with a small shield. In your other hand is your main weapon. This can really be anything from a sword to an axe to a mace. If you want to keep somewhat close to a dual blades weapon you swing around wildly, go for almost straight blades, like a katana. Alternatively I guess you could made a dual tipped spear and a buckler/glove hybrid on your middle hand. Not sure how effective such a setup would be. [Answer] Weapons in games are notoriously oversized. Come on, a great sword that is 1.5 times as tall as its wielder and about half as wide? You wouldn't be able to lift it let alone swing it. So take a note from that and make them smaller. Scale it down so everything but the curving blades covers the hand. That would make the curved blade only extend a few inches past your wrist. This will keep it light enough for a speed/DEX fighter to use. If you make the hilt behind the shield roughly circular then you can flip it from punch/parry/slash mode to stab mode. With the points forward, you may be able to use it to trap an opponent's blade (if the points are long enough). For ambis like me it would be a pretty decent weapon, giving the flexibility to be offense or defense with either or both hands. It would definitely be faster than flipping a short sword so it's blade rests against the underside of my forearm. The main issue is how to carry it when it's not in your hand. [Answer] Warglaives are awesome. While not as versatile as a sword, they have a use: The massacre of demons ('demon' can be interpreted liberally here). Warning: Do not try this at home! Disclaimer: This is 100% theorycraft. I have exactly zero experience wielding glaives (unless... does playing Illidan in Warcraft 3 count?). --- One of the issues you have raised is the **weight** of the weapons. I can imagine that the wooden weapons you have crafted yourself are quite heavy. That's mainly because the wooden weapons are solid. Steel weapons would be partially hollow, but steel is still rather heavy. If construction materials and money are not an issue, which is often the case with legendary weapons such as theses, you have plenty more to choose from. The aerospace sector is always looking for ways to reduce weight on their air- and spacecraft and have done so pretty successfully. Grade 5 titanium alloys are looking good. There are materials available with even better specific strength (strength of a material normalized to its density), but unsuitable for the part of the weapon that you strike with (or may get struck). That's ok for the grip though, and the same is true for the area facing the user. You could fashion those parts out of even lighter material if necessary. The fourth issue you listed is actually the key to using the weapon. You mentioned that you can't effectively use the blade without **spinning** around. Best is to let go of the notion that the weapons can be used in any way similar to a sword. Spinning around (with stretched arms, each holding a glaive) is exactly what you should do. Your arm will only have to worry about providing a pulling force. Combined with the centrifugal force, the weapon will automatically move towards a horizontal place. Counteracting the gravity is done with the same pulling force that you're using to keep the weapon in place. Just make sure you keep gripping the glaive and don't send it flying. Compared to swinging a sword, the latter is rather easy, as you're doing much more with a sword than simply gripping it. For glaives, you don't have to steer the weapons and your arms are not used for the slashing motion, you do that with the rest of your body. Using only a single glaive will throw you off balance. Always use both glaives, or adopt a different fighting style entirely. For glaives to work this way, **aerodynamics** are rather important. While it's slicing through the air, the shape of the weapon may causes forces to act on the weapon that disturbs the circular motion of the weapon. What you want is for the glave to automatically stabilize itself when its not held perfectly flat. Most aircraft are designed that way as well. For example, holding the glaive slightly in front of the center of gravity (with respect to the spinning direction) will makes the blade more stable, in the same way that pulling a pen is more stable than pushing a pen across a table is. Instead of moving the location of the grip, you could also make the trailing part of the glaive a bit heavier than the leading part. I think the question of how to make a glaive to be more like an airplane is a question best saved for a different topic though (and left to experts). Now we have the mental image of a whirlwind made of deadly metal, but I am afraid that won't last. You see, there's a slight problem with this setup. If you spin a few times, chances are you're getting **dizzy** already. Your opponent just has to keep doding your attacks and at some point you will simply fall on your face. This doesn't seem like a very effective fighting style at all! This is where ballerina's come in! They have been spinning on their feet longer than the concept of a glaive has been around (I think). While they haven't found a magic cure, they are living proof that dizziness doesn't need to be an obstacle. They use a technique where they fix their eyes on a fixed point and snap their head around while turning. For figure skaters on the other hand, that's not much of an option, as that would put too much stress on the neck. Their solution? Train, train and train some more. They ignore it. Apparently they can get pretty good at hiding they suffer from dizziness, although they still do. ...better replace that image we had with Illidan as a ballerina. Martial artists have been trying to prove *their* art is the best one ever since we picked up clubs, so I think it is rather pointless to try and prove here that it is at least somewhat effective. I can you tell you this though: Your enemies will soil their pants the first time they see one of you whirling their way. I'm sure some commentators can enlighten us on viable strategies to defend against glaives, but except for the obvious ranged weapons, those strategies are tested literally with the user's life on the line. If that doesn't make them flinch, I suppose it is well deserved if they can prove themselves right. The same goes the other way though, we don't have grandmaster glaive-wielders yet who can teach us the best techniques and glaive designs. Even if glaives don't prove to be on par with other martial arts, I think I can safely say that in the event of a zombie apocalypse, glaives are looking pretty damn effective for getting around town. [Answer] Klingons have a similar Bat'leth weapon as well. Here's why it works... 1. Massively exotic. They don't get used much so when you do see one, it's a unique experience and you're gonna remember who was using it 2. Non-Human usage. We can't make this work, our strength and agility simply don't allow for these weapons use. Instead we need super human traits...Klingons through brute strength and Elves through agility can both achieve this, with the only human exception to this being our stories hero. Both of these traits are not particularly useful in real life, but are fantastic in a story and makes them popular. You need superhuman strength or agility beyond what we currently possess...which in a RPG setting defines many of the characters we like to play (my 18 double zero strength can swing this right?) and in movies will define our heros (I'm pretty sure Bond or XXX could pick two of these up mid-movie and have the audience go along). Unfortunately in Cosplay, the GM (as powerful as they are) cannot grant the superhuman strength nor agility to a player as required to use the item. My recommendation then becomes make it hollow plastic so your cosplayers can swing around a 'metal' blade as if it was light plastic. [Answer] Once you start modifying the design for practicality you're inevitably going to end up with a sword and perhaps a shield. Having an extra sharp blade pointed on the back side of the handle doesn't do anything useful but provides lots of potential to accidentally slash yourself. Removing it would lighten the weapon and allow for a larger range of motion. Now you have two swords. You adjust the blade geometry to something less fantastic and more practical. Two swords isn't too useful so you ditch one of them completely and if it's worth it to lug one around you grab a shield. [Answer] It would be possible to reduce the weight by making the blade perforated, nevertheless it will weaken the blade. To use them in pair offhand one can be scaled down and be used more like a renaissance sword and dagger style. It seems reasonable to remove the central spike and make the whole blade crescent-shaped. Regarding spinning them in combat, as mentioned in some previous answers - that is the perfect way to the grave. I was able to catch people in the middle changing stances in longsword sparring, despite being not the fastest man, so catching a spinning opponent in the back would be not a complex job to do. [Answer] I'm thinking that making the blades curve in the opposite way, away from the body would be a good first step. How many would be heroes are now blind in at least one eye in Azeroth? These things look cool but are impractical in that regard. With any long weapon, you want to keep the sharp bit away from you. So start with curving the blade the other way. You don't really have to change the aesthetic of it too much. The barbs are a little ridiculous, so I'd lose them or maybe turn them in such a way as to make them more likely to catch an opponents blade. The next step is then to make them shorter. Unless you are in a small party or loose melee, you are going to be as much of a danger to freind or foe. Even with short blades, A six foot person would have a span of about 9 feet, blade tip to blade tip. Hazardous in the crush of battle. So make the blades maybe 15 or 16 inches, out from either side of the weapon. This would help greatly reduce the weapon's weight. This gives you an overall weapon length of about 36 inches, which is about the same length as a typical broadsword. It will be on the heavy side due to the additional central blade, so you may be talking about a 3 kg item. You will need to be very strong and have very high endurance to be able to use this for more than a couple of minutes. If you want an idea of how hard this is, just swing around a couple of 1 gallon water jugs for 3 minutes. Your hero is also going to need forearms like Popeye. All of the ability to move these things around is going to rely on the wrist. Further weight savings are only going to happen at the cost of blade strength. You might consider changing the central blade into a spike. This weapon is only really going to be useful against opponents with little or no armor. You won't have sufficient leverage to generate an armor defeating blow unless you can perform some sort of wide swinging strike. You could try punching with the central spike, but if something gets in the way of either of the outer blades, it won't hit true and will be turned by the armor. The more I think of it, this weapon is only really going to be useful in gladiatorial pits. Not a battlefield. [Answer] Well I'm a fan of this twin blades myself and here's a summarized answer: Warglaives are such a huge weapon, and mostly made of metal , it won't hurt if the whole size (end to end) is about from the bottom of your chin to the hips . Why ? Because having a long blade wielded in the middle is hard to balance and very heavy and the advantage of having a shorter blade is having more space and wielding it easier , more space and lightweight , more options , you can use it to stab straight , and do a backstab which is better to have as some of your options rather than swirling forever ,if you want , even if it's short try to make it wider , so it may look like a compressed glaive rather than two medium daggers joined together . Also the reason why you swirl withis warglaives it's because it's circular , why not make the blade straight or facing the outside like a saw , you know to make sure that swirling isn't only your style , but one things for sure , to fight with warglaives is to use your whole body ,like dancing , becoming one with it , well that's about it, well it's just my opinion .hope this comment helps you , and if you make it possible , I would be more than happy to address you as a legend [Answer] I would say the answer would be to: 1. attach the blade to the end of a vambrace, essentially turning your arm into the handle. 2. Make the blades shorter-about half the current length-but thick. Then turn the spike in the middle into a sort of spearhead protruding from the end of the vambrace, with the two blades protruding from behind and to the sides of the spearhead. Now you have essentially created pickaxes. At this point, them being heavy doesn't matter; pickaxes are designed to not only smash, but to *penetrate* on impact. Warhammers and maces are heavy too, but did people use them? YES-*especially* when it came to armored opponents. So, hard to stop them once you get momentum? Good, you *want* your armor-piercing weaponry to be as unstoppable as possible. The idea here is to use broad, powerful swings to build up force. You won't spin unless you miss; whatever you hit will absorb the impact. This means every attack will need your full commitment, as it'll be easy to get these things going, but hard to stop or remove them (like from the ground. Seriously, DO NOT hit the ground)! The strongest attack I can see with these weapons would entail pressing the warglaives together behind your back, side to side, with magnets locking the two together. Then, with a mighty overhead swing, your pickaxes, now essentially one *giant* pickax, come down to sunder or smash right through whatever's in the impact zone. If a guy is on the ground and has his shield over him, this attack should go right through that. To help deal with the weight problem, there are two ways: 1. Mechanical assist-A localized version of power armor would help lift and move the pickaxes, but would require a whole lot more equipment, likely hidden behind armor so it can't be sabotaged and make the user's life so, so very difficult. The result would likely be bulky; I'm thinking of a battery on the back, with exoskeletal "sheathes" on the arms to help lift and maneuver the warglaives so the user doesn't get tired as quickly. 2. Magnets-Magnetic levitation works for trains, so why not warglaives? The magnets would bear up the vambrace, reducing weight the same as buoyancy does underwater. The user's forearms would be floating horizontally to his body; assuming the rest of his arm is hanging down as normal most of the time, this will result in his arms being held in an L when they are in use. The magnets would also help bring the vambraces up or down, before or after a swing. Since the vambraces are floating most of the time, quick, powerful thrusts would be an incredibly good use of the warglaive's central point; like boxing but sharper! ]
[Question] [ How to avoid blatantly time traveling or breaking causality in a big way when getting my characters to places quickly (Faster than light)? The method used is a tunnel in some sort of different space with set entrances that will get you somewhere faster then light would get there. I don’t mind getting hand wavy or just completely ignoring it. If it’s too hard to dumb down something complex I understand. It’s not a feature I plan on focusing much on. Just a tool to get places quick. [Answer] TL;DR: Decide whether any part of your system needs *actual* FTL (and wormholes *do not require this* by themselves, if the mouths get moved at sublight speeds). If you do need FTL, handwave a preferred reference frame. If you don't, handwave in chronology protection, and then just concentrate on the interesting aspects of your setting instead. --- Hawking offered the [Chronology Protection Conjecture](https://en.wikipedia.org/wiki/Chronology_protection_conjecture), suggesting that it is in fact impossible to travel backwards in time (and so form a [closed timelike curve](https://en.wikipedia.org/wiki/Closed_timelike_curve)). On the face of it this seems at least slightly plausible, because there don't appear to be many time travellers here. A suggested mechanism for this, with wormholes at least, was that [vacuum fluctuations](https://en.wikipedia.org/wiki/Virtual_particle#Virtual_particles_in_vacuums) around the wormhole mouths would rapidly build in strength as you attempted to form a time machine with them, causing the wormhole to collapse before a CTC arose (possibly with a bang, possibly turning into a black hole, posisbly both, depending on how your wormholes are made). In Luke Campbell's *Verge Worlds* RPG, he used this as a basis for [warfare against wormhole networks](http://panoptesv.com/RPGs/Settings/VergeWorlds/VergeHistory.php#IntraWormholeWarfare)... a nice example of how things that might seem like unreasonable constraints initially can bring in new and interesting ideas. > > The method used is a tunnel in some sort of different space with set entrances that will get you somewhere faster then light would get there. > > > With wormholes, no-one actually travels anywhere faster than light. Its just that space is no longer [simply connected](https://en.wikipedia.org/wiki/Simply_connected), and there are now two routes between any two points, one of which passes through the wormhole and one of which is the scenic route. Things like *Orions Arm* and *Verge Worlds* have wormhole networks that are deployed at sublight speeds and form *trees* rather than graphs with cycles (because cycles are [Roman Rings](https://en.wikipedia.org/wiki/Roman_ring)), so there's only one route between two points in the wormhole network, and that puts some significant restrictions on how your setting can work, which doesn't always play nicely with the sort of universes people want to write about or play in. The critical thing is that the mouths of the wormholes are never moved at FTL speeds. If you can open a wormhole mouth at an arbitrary point in space, instead of having to fly it there the hard way, then *that's* FTL magic, and you start running into issue like the [tachyonic antitelephone](https://en.wikipedia.org/wiki/Antitelephone) (or Tolman's Paradox). And that's where most FTL flight/communication/teleportation issues arise. FOr more informnation on this sort of thing, various related answers on this site reference [Sharp Blue: Relativity, FTL and causality](http://www.theculture.org/rich/sharpblue/archives/000089.html), which explains that even if you can't FTL into your own past with one jump (or message), with a second FTL event All Bets Are Off. Ways around that restriction will tend to make things handwavy and soft-scifi-y, and I'd like to point out that *these aren't always bad things*, so long as they let you make the setting that you want. The excellent suggestion by Someone Else in the comments (referencing [this answer](https://worldbuilding.stackexchange.com/a/47167/23873) by JDługosz) describes what a "safe" FTL system might *look* like but doesn't explain the *why*, but you can just handwave in some Chronology Protection that means that trying to do FTL that results in a CTC causes your jump drive or teleporter or remote-wormhole-mouth-opener to go *foom*. You can invoka [preferred reference frame](https://worldbuilding.stackexchange.com/a/47167/23873), ensuring there's a point of view from which physics still looks fine and that's the one that everyone can agree on. Another of JDługosz's answers [also covers this subject](https://worldbuilding.stackexchange.com/a/47038/62341). [Answer] The universe may have an in-built mechanism for causality protection, preventing wormholes specifically from forming time machines. --- Wormholes as we understand them don't *always* form time machines. They can be arranged safely and even into complex chains/networks while remaining stable. The trick is to balance them spatially and temporally. Let's look at an example where two wormholes form a time machine. Like everything else, wormholes experience relativistic effects like time dilation. Let's create 2 wormholes, A & B, side by side and synchronized, and send B off to some distant star 100 ly away at near the speed of light, while keeping A here at home. Measuring B's transit with Earth clocks, we'd expect it arrive in 100 yrs. However, according to clocks traveling with B, the trip from Earth to the distant star takes only 1 year. There's nothing strange about that. That's basic time dilation. However, this is a *wormhole*, and we have the other end point to consider. A and B contain the same set of points in space-time. Looking through A, situated on Earth, we see B arrive in 1 year. *After only 1 year of flight, astronauts step through wormhole A and visit the star system 100 ly away.* You might think that's impossible. After all, we can look through a telescope on Earth and still see wormhole B in flight to the star, with 99 ly to go. But that's relativity. If you attempt to catch up to B, you'll never reach it before it reaches its destination. In its frame of reference, the 100 ly distance is length contracted to only 1 ly. In its frame, the star isn't 100 ly away, but only 1 ly, and its frame is just as valid as any other. Anyway, wormhole B is now 99 years in our past, and any astronaut stepping through arrives 99 years in our past. They will have "time traveled". However, with the current arrangement, there's no way to communicate with Earth before the wormhole's departure. Lightspeed messages through space from the star still take 100 years. The astronauts may be situated -99 years temporally, but they are situated +100 years spatially. That's the rule. A wormhole's temporal offset must be less than its spatial offset. If one wormhole endpoint sits 1 second into its counterpart's past/future, then the two cannot come within 1 light-second separation without forming what's known as a closed time-like curve (CTC), which is what time machines are made of. --- So, how does the universe exhibit an in-built safeguard? A CTC is a loop. It is a trajectory through space-time whose endpoint lands on its own start point in both space and time. Imagine a photon traveling along this path. It travels the entire path and constructively interferes with itself in the past, back at the starting point. The new doubled photon then travels the same path and again constructively interferes with itself in the past, quadrupling, and so on. The photon energy ramps up towards infinity in zero time. This resonating effect isn't limited to light. According to Matt Visser, "Lorentzian Wormholes: From Einstein to Hawking" (1996), if you look at what happens in semiclassical quantum gravity, you will get a buildup in the amplitude of quantum fluctuations on the cusp of forming the time machine, an effect called "vacuum polarization". These fluctuations are expected to build sufficiently to destroy the time machine, before a CTC can form. So, when you try to bring two descynchronized wormholes to within their hard spatial-temporal separation limit, this effect destabilizes and destroys the topology, rendering them no longer wormholes. Maybe they dissipate harmlessly as gravitational waves, or maybe they collapse into black holes and dump a few gammas out while they're at it. Because of strangeness, it's also possible that the wormholes "bounce" off each other, so as to prevent time machine formation. [Answer] You could just say that time travel doesn't happen. No, really - this isn't a cop-put. Sometimes nature is just like that. Suppose you are looking at the Andromeda nebula. If you have good sight and it is dark, you can see it with the naked eye. Light is both a particle and a wave. The light has been spreading out as a wave for the last 2.5 million years. It could be anywhere on a sphere with a 2.5 million light-year radius. But if it is detected as a particle, all the energy is dumped within one cell in your retina, and the rest of the giant sphere gets nothing. How does nature organise this? Does the fact that your head got in the way of the photon just *here* have an instantaneous effect over the rest of this giant sphere? It seems it does. The light wave does not seem to contain hidden information on where in the wavefront the particle *actually is*. You cannot use this to pass useful information faster than light. Well, some people hope a way may be found, but I doubt it. For a bit more on what light does, read about [Bell's theorem](https://en.wikipedia.org/wiki/Bell%27s_theorem). By analogy with Bell, the no-time-travel clause could be called Wossname's Theorem, or the Wossname Inequality. That would fit with there being a hypothetical limiting process, but no-one knows how it works. [Answer] ## No Loops The easiest way to ensure that there isn't any time travel is to make sure that there are no loops in the wormhole network. They need to form a tree-like graph with only one path from any place to any other place. With no loops, if you travel from A to B, then the only way to get back from B to A is along the same path in the opposite direction, which would undo any of the time changes. You may end up with travelers aging at different rates, but nobody will arrive anywhere before they left. One way to explain the no-loop requirement is that there is a single source from which the network is projected, and something horrible would happen if you projected two wormholes to the same planet. [Answer] ## Time travel is *not* a consequence of no-preferred-frame I am familiar with the problem you're worried about: it plays an important role in the novel *Exultant* by Stephen Baxter. But I think it's a misconception. The reason FTL can't result in time travel is that remote frames can't impose their own timelines on each other. Consider this thought experiment: physicists think that time might actually run backwards inside black holes. So, pretend you have a spaceship that lets you go into a black hole, hang out for two weeks, and then come back out. What would happen? * You and your ship would "age" backwards while inside the black hole. Decay processes driven by entropy and the arrow of time would play backwards for you. The spoiled milk in your ship's fridge will un-spoil. * The rest of the universe will *not* be rewound in time, for the simple reason that running *your* clocks backward doesn't cause the clocks in *the other parts of the universe* to run backward, too. They were unaffected. Now let's consider a less absurd scenario: two star systems whose individual frames have been drifting part in space and time for billions of years: time is running forward in both, but each has a different age-since-the-big-bang because their clocks have been running forward at different speeds. Your heroes pop into a ship and travel from one to the other instantaneously. They spend two weeks playing Space Poker, and then flit back home. Again, the reason this cannot result in time travel is because the frame back home has its own clock that has continued to tick at its own rate throughout. Now, it's probably true that the amount of time that has passed for Earth during your space-poker trip is different than Space Vegas, but Earth still moved forward in time. Even if Space Vegas ran *backward* in time, that just means Space Vegas's physics has been running backward, *not* that it has become connected in spacetime to an earlier segment of Earth's world line. You can't use FTL to reach an earlier time in any single frame. It may be true that calendars in Space Vegas say 1975 while Earth says 2023, but when you come back from Space Vegas, the calendars in Earth will still say 2023+. That's true whether you return faster or slower than light. [Answer] **I'm going to re-post a modified version of an answer I made to a similar,previously asked question**: The simplest solution is to assume that the 'laws of physics' including those pertaining to the creation of wormholes (WH) prevent anyone from using WH that violate the chronology protection conjecture (CPC). As as a result the **CPC is no longer a 'conjecture' it is a fundamental principal of physics**. The basic idea would be that all WH start off as small, unstable sub atomic 'seeds' that have to be spun up to usable sizes using exotic matter. This makes WH expensive to bring up to sizes large enough for useful travel. As a result they are precious assets. Also and only if you want you can make it a requirement of your universe that the one end of a WH has to be 'towed' to its final destination point by an automated probe. As a result you only have FTL travel from point to point once it reaches that destination. Want to travel 1000 LY? Sorry, you have to wait however long it takes for your probe to get to your destination and drop off its precious cargo while it travels at a % of the speed of light. (Annoying isn't it.) You can also write into the background of your story that shortly after WH were first discovered or created experiments were conducted to determine if they could be used to violate causality. These experiments proved conclusively however that any attempt to do so caused the WH involved to 'collapse' the instant the attempt was made. You simply can't send meaningful information back in time through one. And in this context mass is also 'information'. It doesn't have to be a violent explosion (though it can be if you want it to be!). The end result is the same though. The instant a particle or photon enters a micro-sized WH that potentially violates CPC the WH falls in upon itself and radiates out its tiny mass as sub-atomic particles. You can choose any description of the process that best suits your purposes. But the result is a world where only non-CPC defying WH are stable and useful for the transfer of information and cargo. No time machines. [Answer] Well, let's break this down a bit. ## First, what is the actual problem with FTL travel? According to special relativity, kinetic energy is asymptotic as you approach light speed. This means that traveling at light speed requires infinite energy. And contrary to contemporary usages of the term "infinite", what this really means is you can never gather enough energy. If you brought every object in the universe to a single point, at a standstill, and robbed it entirely of thermal energy, you would still not have enough energy to accelerate a baseball to lightspeed. And faster than that is simply excluded from the domain of the equation. Asking what happens when you exceed lightspeed is like asking what happens if you make a triangle with sides of lengths 2, 3 and 40. Well, if you have those segments, you don't have a triangle. But let's handwave that. ## If we could do it anyway, is that really the same thing as traveling back in time? The "speed of light" is kind of a misnomer. First of all, light doesn't travel at a constant speed. It travels at different speeds depending on the medium it's traveling through. And the difference in these speeds is responsible for the phenomenon of refraction. The universal speed limit really has nothing to do with light; light is just an easily observable and easily understandable example of it in work. Light travels at light speed in a vacuum because, well, that's as fast as it can go. The real cause of the universal speed limit is causality, the idea that causes precede their respective effects. Special relativity is really an observation that causality depends not only on time, but on space. A better term for the universal speed limit than "speed of light" might be "gradient of causality." In order for one event to result from another, the effect must be within the region of spacetime where its delta time is greater than its delta space times the gradient of causality. In other words, it takes time for a cause to propagate through space to trigger an event, and the relationship of the amount of time to the amount of space is the universal speed limit. For example, if a star burns out ten lightyears from Earth, that's a cause, and us observing this is its effect. Because the cause and effect are ten lightyears apart, a minimum of ten years must pass before we can observe it. Anything faster would be a violation of causality. Now, if we look at the passing of time as a series of events, we can see how these events have to "slow down" as we speed up. For example, The time must be 12:00 before it can be 12:01, so these two events share a causal relationship. So if we were to, at exactly 12:00, accelerate a clock all the way to lightspeed (which is impossible, but remember, we're handwaving that), and send it ten lightminutes away and abruptly bring it to a halt, it would take ten minutes to get there, but so would the propagation of the 12:00 event, so it would not show 12:01 until one minute after it arrived, even if the clock is functioning normally. If we then sent it back to Earth at exactly 12:01, again at lightspeed, the clock would still say 12:01 when it arrived, even though the time on Earth is now 12:21. Here's a diagram of what it would look like if we sent a clock ten lightminutes away and immediately back, both FTL: [![FTL clock](https://i.stack.imgur.com/Ygkoi.png)](https://i.stack.imgur.com/Ygkoi.png) Following the time axis to the right, we first send the clock at 12:00 (blue line) and the event begins propagating (red line). Then it arrives at the point ten lightminutes away, and begins to return (blue line), while the event begins propagating (red line). Then the clock arrives back at Earth (depending on the actual speed the clock moves at, this could be before or after 12:10, but in the diagram it comes before). At 12:10, the Earth departure has had time to propagate 10 lightminutes and it begins to "echo" back to us (green line). A little later (some time after 12:10), we can observe that the clock has arrived 10 lightminutes away. Then finally, at 12:20, we can observe that 10 lightminutes away could have observed the clock leaving Earth. Now, aside from at the initial point, what time the clock says is anyone's guess. It can't be after 12:00 because 12:00 hasn't happened yet. But there's also no reason for the clock to tick backwards. Whatever it says is a violation of causality (but then again, so is the whole thing). We also have some unexplained oddity in terms of our causal echoes. But in our frame of reference, it doesn't actually arrive before it left. # Conclusion Looking into causal echoes and the reverse observation of events when FTL happens could be interesting, but just like audio echoes, I don't think anyone would complain if you just didn't mention them. [Answer] ## Differentiate between light cones and universal now In theoretical physics, there is a concept of "universal now." People who don't actually understand relativity insist that there is no *universal now* because they heard the phrase "no privileged frame of reference," and think that the latter prevents the former. This is not the case. What it really means is that the rate of time in one location isn't beholden to the rate of time in another location. Neither is the "right" or "correct" rate of time. Neither is privileged with that designation. A light cone is an expanding sphere of space within light-speed distance of any event. The functional rule of causality is that nothing outside of an event's light cone can effect the event that the light cone is expanding from. For a light cone to exist, there has to be a consistent flow of time in all locations. It might not be happening at the same rate, but everything experiences *now* at exactly the same instant. Causality violations are less specific than a light-cone violation. They state that you can't go backwards in the universal now. If you can teleport, it basically turns the cone into a flat plane. If you have good enough telescopes, you can literally see into the past of the other location. This is not a causality violation because you can't actually visit that past. Teleportation creates a local violation of thermodynamics by transferring your state from one place to another, but it isn't a causality violation. [Answer] If you travel back in the past, you are just no longer executed by the simulation that runs the universe. Its like beeing memory pasted into amber. You float forever preserved in some past flickering second, with not consequence whatsoever rippling into the future. [Answer] It sounds like you are referring to a wormhole. Think of space like a piece of paper. Ordinarily it may take quite some time to traverse from point A to point B on the paper. But if I were to bent the paper so that point A and B were to touch, then I could move, effectively instantaneously, from point A to B. The equivalent in our three-dimensional universe would be a wormhole. It sounds from your question that these wormholes are fairly permanent (a tunnel to "set entrances"). With a sheet of paper, it would be hard to fold it where several different points are in contact but not the rest of the sheet, but that's inconsequential. Maybe spacetime fabric is more stretchy/flexible. Personally as a reader, it'd be fine just to call it a 'teleporter', 'Doorway,' 'portal' or 'wormhole.' Naturally, I'd want an explanation as to why it worked, who built it, etc., but if you sculpt the scene right, you can get away with just calling it a wormhole without having a 15-page scientific breakdown. ]
[Question] [ In this world, most things that could be considered animals or animal-like reproduce in a genderless, sexless, or asexual manner, primarily through processes like apomixis or other means excluding birth(either from womb or egg) which excludes parthenogenesis. However, in my **personal** opinion (which may not be biologically, philosophically, or morally and politically correct), if a creature gives birth, it is considered female for the purposes of this question, irrespective of how alien its appearance is or whether the entire species has only one gender. The only entities that possess: -Sex -Gender -Anything related to sex, are fantasy/alien humanoids/semi-humanoids, including humans, and possibly some bacteria or other smaller creatures in this world. The question arises: Can this world truly exist, and if so, how would these creatures survive when sex offers so many advantages? Advantages: As far as I know, genetic diversity is a great advantage, and sexual animals tend to be selective with their partners, which creates competition, which itself is good, people and species that decide to not compete, are outcompeted. Details: Regardless of my lack of understanding of sexual biology, reproduction where the individual can just split itself into two to clone itself or release roots/pieces of the body that can then grow into full adult animals, or spores and similar things are preferred over things like lying eggs or giving live birth. [Answer] We have only one data point to work with: Earth. Worse, as much as humanity has learned about genetics and the evolution of life, we're really just scratching the surface of the subject. We're getting better at "why did it happen this way?" but we're still a long way away from casually answering the question, "OK, so why didn't it happen that way?" But, while our mandate is to help you build an imaginary world (by definition, you control all of the rules of your world), one of the more satisfying goals of the Stack is to help you *rationalize* the world using what we know about Real Life. **A quick divergence** Just to make a point, when it comes to reproduction things are a bit more complicated than just sharing DNA and moving forward. For example, an observation from our sister Stack, Biology.SE: > > Take bees for instance. There are basically three types of individuals in a hive: one female queen, which lays eggs, male drones which fertilize a queen (or try to), and then die, and neuter workers, which feed the queen, raise the eggs & larvae, and determine whether a particular egg will become a new queen or drones. > > > So for bees, only two types of individuals actually participate in sex, but all three types are required for the hive to survive and reproduce. ([Source](https://biology.stackexchange.com/a/77375)) > > > While you're asking if you can have a world that's fundamentally sexless in pretty much all cases, it's worth noting that we should avoid the temptation of creating all life (or manipulating the representation of life) in the image of humanity. When you get into bacteria and fungi, there can be many more sexes involved in reproduction than just two. Or three. Or four.... Why this quick diversion? We're going to need it a bit later. **Why did nature evolve multiple-sex reproduction?** > > Those species that exhibit sexual reproduction have an evolutionary advantage over "cloners" in that there is more diversity in their offspring. This diversity allows the species to adapt more quickly to a changing environment, or to increase its chance of survival in the existing one. — [Tim Waterfield, Cambridge England](https://www.theguardian.com/notesandqueries/query/0,5753,-21870,00.html) > > > I'm no biologist, but if I remember the basics, life started as sexless cloners (that's really what you're asking about. Please correct me if I'm wrong). As time (and meteors, and ice ages, etc.) moved on, "life" discovered that hedging its bets was a good idea. From that perspective, a world that evolved *with fewer life-altering and life-ending catastrophes* might favor single-sex life over multi-sex life. Thus, we have the answer of "you can have it" with a reasonable rationalization. **But it might be more fun to hedge your bets a bit like the bees** What if life on your world is, indeed, a bunch of cloners... that evolved "helpers" like the neuter sex in the bee world that acted to ensure the continuation of the species, *but never assist in the actual act of procreation.* The idea meets your basic desire of not wanting "females" (e.g., not wanting a second or more participants in the act of procreation), but it feels more "real" in that "life" (the mindless process of evolution) came up with a way of better preserving the future — even though it did it without using the generally binary sex model developed here on Earth. [Answer] # Have most life be starfish like Most life on your planet can be based around organisms like starfish with somewhat decentralized brains spread across multiple limbs. They can reproduce by splitting and making copies. This will make evolution of intelligent life notably harder since you're cutting off a lot of routes to intelligence, but stories tend to involve a lot of luck anyway. # Have a plague block sex Have some sort of common bacteria actively interfere with sexual reproduction. Anything that evolves sexual reproduction will tend to die on this planet. That will remove the advantage of sexual reproduction. [Answer] I believe there is a life form on this planet that exhibits what you are looking for. The zygotic adult gives off gametic spores. If a spore lands in a viable location, it grows a small organism. When a second spore lands on this, a zygote is produced and an adult grows. They are called [Ferns](https://en.wikipedia.org/wiki/Fern). [Answer] If you're talking alien biologies, then you have options. The purpose of sex is to allow recombination of genetic structures, both for improvement and for resilience. I'm sure you're familiar with the "improvement" end of evolution, but it sounds like you aren't considering the resilience end of it. Without genetic recombination, you get monocultures. This results in cases like the banana, where an entire species is susceptible to a virus, bacteria, or fungus. We've already had cases where entire species of banana have been wiped off of the planet by a single infection. Recombination doesn't require distinct sex/gender assignments. Most plants are hermaphroditic. They all produce pollen, and they all have flowers. The pollen is the transmission mechanism, and the flowers are the incubation mechanism. There are actual cases of "spermcasters" and "broadcast spawners" in the animal kingdom. Coral comes to mind. When mobility is available, this allows selectivity of breeding partners, which is a far more effectual genetic strategy. You may find this paper interesting: <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5031625/> Overall, you don't have to go very far to find examples of genetically recombining creatures without gender, but they are always hermaphroditic. You need a sender and a receiver. [Answer] The "advantages" of sex are less obvious than it seems. What is the benefit *to me and my genes* of my species being genetically diverse - why should my genes care about them? They only care about their own reproduction and increase. Being selective about partners is a consequence of sex, not an advantage. Indeed the more you dig, the less obvious advantage sex seems to have. So have your species divide by "budding" (although I don't really see the difference between "budding a child off the exterior" and "budding a child in a womb". Or splitting, or setting spores that develop into a plant-like autotroph which in the alternate generation produces babies... All of these will produce clones - and this isn't a problem per see. I'd say in such a world, there are no *males* (female is the default, males are a modification of female, at least in mammals) Or you can still have sexual reproduction, just without the sex: Every spring we go down to the sea to release our gametes into the ocean. Our "children" swim with the plankton for a few years and the lucky few that don't get eaten eventually crawl on land, metamorphose and start their adult life. You get the genetic diversity of sex, without giving birth. (for added ickiness, have the adults die after spawning - Futurama had something like this.) You'll need to work through the consequences of all this. But there is no fundamental law of nature that you're breaking. [Answer] ## They do not breathe oxygen It is certainely not completely proven yet, but a great deal of research are pointing that way: > > [One major advantage of sex may be its promotion of recombinational > repair of DNA damage during meiosis](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC209837/) > > > If your creature do not breathe oxygen, they may never have evolved to sexual reproduction, and continue to use some form of cloning for reproduction. For monocellular creatures, cloning is trivial and the "offspring" quickly mature to the same size as the "parent". For more complex creatures, you cannot have a direct cloning of a full size adult, you'll have to have the parent release a mini-clone (I know you don't want to call it an egg but at this stage it becomes just semantics). A single stem cell which will multiply and diversify into all the organs needed for the creature. You can then choose how your "parent" creatures handle the rearing process. It can go from "just drop it somwhere and let it be" up to "drop it in a sheltered area, watch over it and protect it until the clone reaches maturity", with everything in between allowed. Note that some ratio still have to be respected. For example in the case of just "dropping the clone" somewhere and letting it take its chance. If the clone chance of survival until adulthood is 1%, then it means the parent will have to drop at least 100 mini-clones just to ensure the specie survival. --- The long explanation: The first organisms were all sexless cloners. They powered their life processes by extracting chemical energy from the minerals in the soup around them. Then some organisms (cyanobacteria) discovered (or rather evolved) photosynthesis. Yay, they thought, now we can get our power from the sun instead of having to lick the side of underwater mounds (hydrothermal vents). That also came with an advantage, sunlight is way more abundant than localised hydrothermal vents. So yipee, these organisms thrived and spread across the whole water near surface instead of being limited to specific locations. This worked so good for them that quickly their sheer number started to upset the balance. The byproduct of their process is dioxygen (O2), and they were all releasing more and more of it. Problem is at the time oxygen is a poison for anything alive. The explosion of the cyanobacteria population is thought to have caused the [Great Oxidation Event](https://en.wikipedia.org/wiki/Great_Oxidation_Event) which raised the percentage of oxygen in the water and in the atmosphere. This unfortunately killed between 80 to 99% of species at the time (by direct poisoning but also because the now free oxygen started to react with the iron and other minerals, depriving some species of their food supply). But life finds a way. Some survivors of this great extinction decided to tackle the problem head on. Instead of fearing the oxygen, and since there was so much of it, let's make use of it. And presto, some organisms evolved to use oxygen to power their life process (one of them is your gran-gran-gran mother/father, still no sex at the time). On it went, the population of aerobic organisms grew, but they were soon faced with another hard problem: Breathing oxygen and having it power the biological process in your cells means the oxygen must be present in the cell at some point. And oxygen is extremely corrosive, it wants to react with nearly everything, including the amino acids which form your DNA. Give it enough time, and one day some oxygen will damage your DNA. Now if you are a cloner, when you reproduce, your clone inherits a copy of your DNA. If this DNA was damaged, your new clone's DNA is already damaged from the start. Then it gets damaged further, and you clone a new you with even more damage. You see where this is going, the damages are cumulative and over enough generations you could loose enough DNA to affect primary functions and become unable to live on (or to reproduce). But once again, life found a way. Back to the first quoted sentence, sex is a great way to mitigate DNA damages caused by oxygen. When you combine the genetic materials of 2 individuals , the recombination process will only keep one final version. If one of the DNA sequence was damaged in a parent and not in the other, the recombined DNA of the child has 50% chance of getting the undamaged sequence ... compared to a cloning process where you have 100% chance of passing on the damage. Ok that's obviously oversimplified near the end, and the real number is not 50%, but it's to illustrate that it was for nature an excellent way to hedge the bet. [Answer] It seems to me you are asking about the plausibility of two different things. First, whether most life could reproduce **asexually**, i.e. without combining genetic material from different individuals. Second, whether organisms could reproduce **without a dedicated reproductive stage** in its life cycle, such as a foetus, egg or seed, or alternatively with a very small one. I assume the distinction you draw between an 'egg' and 'spore' is one of size. And presumably you still want a range of organisms similar to Earth's, including plants and animals in particular. ## No Genetic Exchange From a genetic perspective, life on our planet has two mechanisms for sex. Bacteria have a subset of their genes in a separate package - a plasmid - that can be donated to another bacterium that accepts those genes. Eukaryotes - anything with a cell nucleus - have a more organised mechanism where two cells fuse completely and the new cell has two copies of all the genes. In both cases, a cell is accepting genes from outside. This dilutes its own existing genome, which on the face of it is bad for its existing genes, but nevertheless organisms have evolved to do so because of the great benefits that can come from new genes. So how to stop sex evolving? One way is to make the costs even higher, and in a sense self-imposed. Suppose the greatest threat to early life on this world was viral infection, i.e. the insertion of foreign genes. Survival would depend on eliminating any genetic material from outside, and at all costs not allowing it into the host genome. As viruses become more insidious, cells would evolve measures to destroy incoming genes (restriction enzymes, for example). Think of it as similar to rejecting a transplanted orgen. These defences would be more powerful than in our world, and would prevent sexual reproduction ever geting a start. If two cells were to fuse somehow, their defensive molecules would attack each other until one or both genomes was destroyed. With sex out of the question, it is hard to say whether complex multicellular life could evolve. Most evolutionary biologists think not, but we won't know unless we discover other planets with strictly asexual life. So populate your world with whatever you like - except for sex-related structures such as flowers or peacocks' tails. ## Sex, But Not as We Know It There are various possibilities here, but I'll only describe one. This does involve sex in the genetic sense, but without females. I mentioned above that eukaryotic sex involves the fusion of two cells with different genes. It is a waste of time, effort and opportunity if two cells with the same genes fuse, yet because cells divide, nearby cells will often be genetically identical. The solution is for cells to have different types. A cell of a given type can divide into two cells of the same type, but can only fuse with a cell of a different type, and therefore different genes. We are familiar with multicellular plants and animals, which have only two mating types. In this situation, and especially when organisms become multicellular, there is a perhaps-inevitable tendency towards anisogamy. That is to say, the gametes start off all the same, trying to compromise between carrying enough nutrients to develop and being mobile enough to find a partner. But it is much more efficient for one type to grow large and well-stocked - an egg - while the other is cheap, lightweight and optimised for dispersal - sperm or pollen. But two mating types is not the only game in town. Other organisms, fungi especially, can have more than two, sometimes dozens or hundreds. Gametes of any two different types can fuse. Because they don't know their type of partner in advance, they cannot specialise like sperm and ova. Without egg cells, species would reproduce sexually through spores in the air or water, like mushrooms. Asexual reproduction is possible too - organisms might divide or bud in the summer, then in the autumn switch to producing spores. This genetic system doesn't actually *preclude* more familiar methods of reproduction. You could have three or more types, and females would be disinclined to mate with males of their own type. Perhaps that's what the humanoids do. Of course, this is just an outline, I have omitted many details, such as whether the haploid or diploid phase dominates the life cycle. [Answer] If you're talking about **sex**, then the short answer is **no**. Males are the non-egg producing part(s) of a species with two or more sexes. (Though, I suppose that if all of the females had died off for some reason, then the answer could be **yes**, but that would mean it's a species that's likely doomed to eventual extinction.) Of the various [sexual systems](https://en.wikipedia.org/wiki/Sexual_system), the closest you could get is probably [androdioecy](https://en.wikipedia.org/wiki/Androdioecy), where the population consists of only males and [hermaphrodites](https://en.wikipedia.org/wiki/Hermaphrodite). Note that androdioecy is very rare on Earth. Another alternative would be that they'd be sexually male for most of their lives, and only be female or hermaphroditic during a portion of their lifetime. This changing of gender throughout a lifetime is known as [sequential hermaphroditism](https://en.wikipedia.org/wiki/Sequential_hermaphroditism). If you're talking about **gender**, then **yes**, since sex and gender aren't the same thing, and gender is really just a social construct. You could have a species which all expressed traits and preferences which our society would typically think of as "male," thus we would gender them all as male (though, they might see finer differences between the behaviors of their sexes than we do). You see this in literature regarding dwarves occasionally, where there is little [sexual dimorphism](https://en.wikipedia.org/wiki/Sexual_dimorphism) between male and female dwarves, meaning that male and female dwarves look and act essentially same, both having beards, etc.. Hope that helps! ]
[Question] [ The idea here is that a commander of an army intentionally caves in a cave for a tactical benefit, and this needs to happen quickly. The best ideas i had were either explosives (obvious, but maybe doesn't fit a medieval setting that well.), setting fires in a ice cave, or redirecting a river to either fill (not technically a cave-in, but it fulfills the same purpose), or put too much weight on the cave roof. The river idea seems like it could take to long. Perhaps waiting for some type of weather could make sense too. Edit: Bit unclear, i'm assuming a early 1300s european setting, without gunpowder. [Answer] The traditional use for induced cave-in was in undermining castle walls during a siege; this was part of the job of "sappers" who would *tunnel* under the wall using wooden shoring to support the tunnel, then set a fire that would burn out the shoring and allow the tunnel to collapse and undermine (this is the origin of that word, by the way) the wall so that it, too, collapses (allowing the besieging force to bypass the defenses of the fortress). This doesn't come close to working for a naturally formed cave, however; those are generally old enough to have stood through earthquakes, any weather phenomenon that's actually possible for their location, and a weight of overburden that won't be affected by any amount of additional material that can be piled on top in a reasonable time with medieval technology. The one reasonable chance is, if you're in the equivalent of the 14th century or later, it might be possible to *pack the cave with gunpowder* ahead of time, and then set it off at the appropriate moment. This will require very nearly filling the entire space, since gunpowder is far less powerful than modern explosives, but powder was used for mining almost at the same time it was used in the primitive early guns, so it's not an idea that would be "pulled out of the air" so to speak. Additionally, this application has much less disadvantage for slower burning, more primitive forms of gunpowder (as compared to the milled, pressed, and corned powder that was made in the 19th and 20th centuries). [Answer] The only quick way (assuming there is no magic involved) takes a lot of time and planning. It involves digging out any natural supports (in the cave and at its edges) and replacing them with man made supports. then it is only a matter of knocking out or burning the man made supports. They used this to collapse mines during those times. In this case, the mines were built with the man made supports preventing collapse in the first place. This is kind of like the case of the actor who spent a decade becoming an over night success. [Answer] **You have an army. Use it.** <https://www.livescience.com/34608-break-stride-frequency-of-vibration.html> > > In April 1831, a brigade of soldiers marched in step across England's > Broughton Suspension Bridge. According to accounts of the time, the > bridge broke apart beneath the soldiers, throwing dozens of men into > the water. > > > After this happened, the British Army reportedly sent new orders: > Soldiers crossing a long bridge must "break stride," or not march in > unison, to stop such a situation from occurring again. > > > Structures like bridges and buildings, although they appear to be > solid and immovable, have a natural frequency of vibration within > them. A force that's applied to an object at the same frequency as the > object's natural frequency will amplify the vibration of the object in > an occurrence called mechanical resonance. > > > Your army is stationed around the cave. Personell jump up and down in time, possibly with the help of a drummer or drum corps. Changes in the cave according to jump frequency are watched until the frequency matching the cave's resonant frequency is identified. The drum corps seriously gets into it and the army jumps up and down until the cave collapses. [Answer] Your settlement is on top of an old, abandoned salt mine and is supplied by a lake. The enemy commander then sends a team of sappers to dig a tunnel connecting the city's water supply to the cave. The water dissolves the salt along the walls, causing the ground to soften and everything around the hole is sucked into the cave. The results are similar to what happened to Lake Peigneur's salt mine. <https://en.wikipedia.org/wiki/Lake_Peigneur> There's a video of it. The lakeside forest and most boats on the lake were gone in less than a day. [Answer] Sure. It's a question of mining (digging, not explosives) in the right fashion, and providing shoring (that's beams that hold up the roof) in a way that they can be easily removed. Basically, you want a lot of rocks and such on top of the shoring, in a way when the shoring is removed the rocks fall right away. You can achieve this either by having a larger tunnel, putting in shoring, then piling rocks on it. Or by having two tunnels, one over the other, and digging in the floor of the upper one to make sure the lower one's ceiling will collapse as soon as the shoring is removed. Then the upper tunnel is blocked, hidden, etc. If explosives are allowed, you put explosives on key locations on shoring beams. This can produce a cave in quite rapidly. If explosives are not allowed, the prep of the shoring is more delicate. You would need to have some kind of wedge that can be removed and allow the shoring to collapse. If you are kind to your people, that happens by pulling a rope of some kind, your people being out of range of the collapse. You might also be able to do it by setting fire to the shoring beams, but that is less reliable and takes longer. [Answer] ## Hydraulic Blasting If you can divert a river into the cave, if the cave is not able to flow the water out fast enough, then the cave experiences outwards pressure. These forces are enormous, often enough to blast an entire mountainside away. In fact, the Romans mined gold this way. The devastation has to be seen to be believed. You do need the correct geography and very likely (but not definitely) a pipe or small aqueduct. [Answer] If your cave has a large chasm and a narrow ledge, then destroying a section of the the narrow ledge will serve the same purpose as a cave-in, but would be easier to achieve. Or, if your cavern has a natural vertical shaft, the army can climb up into a different passage via rope and grappling hook, then roll a boulder down into the shaft to block it. Similarly, if you have an existing natural barrier inside the cavern like an underground river or giant chasm, you can use that as an obstacle. If so, one army can cross by boat or rope, and take their boat/rope with them, then delay the other army from crossing by firing arrows at them. A monsoon can flood part of the cave if it starts raining. If one party is inside the cave and the other outside, then triggering an avalanche over the cave entrance **or exit** with rock or snow is fast and relatively easy. ]
[Question] [ Let's say there is an ecosystem with lots of familiar organisms. Bacteria, plants, fungi, metazoans. Then a great deal of high-tech waste is introduced into that ecosystem. First, is there any way that familiar organisms could benefit from that? Are there any biochemical processes that could use processed silicon, copper, plastics, etc.? Moving further, what might cause those organisms to begin "unintentionally" availing themselves of complex properties of that waste, like the ability to perform calculation? Is there a series of gradual evolutionary steps that could make such a thing plausible? Could something like a brain-computer interface arise "naturally" in the right conditions? I realize that human inventiveness is itself evolved behavior, but I'm wondering if these kinds of complex and subtle interactions could arise through other selection processes. [Answer] ## Extremely unlikely There are two major hurdles: 1. there is not nearly enough uniformity in the high-tech waste. 2. the life-form will probably need to be able to precipitate metals in its biology (which I think is either rare or unheard of in reality) Evolution relies on trial-and-error at an astronomical scale. For this scenario to play out, you'd need countless individuals to each encounter an identical piece of tech refuse, so that one era's not-fatal juxtaposition could, over many generations, turn into a harmless pattern, and eventually develop into a useful bond. You'd need there to be at least one common piece of electronics that very frequently appears in exactly the same state as far as physical form and functional state. You'd need a practically unlimited supply of those exact parts, and that supply would need to be uninterrupted over geological time. ### How might that happen? Imagine a scenario where a massive supply chain is completely run by an artificial intelligence whose masters have long gone extinct or abandoned it. This supply-chain makes electronic wrist watches, and it's completely self-sustaining: it finds the raw materials, extracts and refines them, manufactures all the parts, and assembles them into working watches. But now its masters are dead. (The watches are slow, so the masters lost track of time and missed lunch, and dinner, and breakfast, and got fired from their jobs -- not for being late but for being unproductive -- and their mates left them and so one day there was no next generation.) So the watch parts are piling up in the warehouse, and similar pile-ups have occurred at every stage of production. For tens of thousands of years, every factory that existed or has been built has eventually filled up and overflowed with its finished output. A hundred landscapes blanketed in those tiny screws. Lakes of watch hands. A mountain of crowns, glistening darkly against the rocky landscape. Is this "high-tech waste?" Well, it's not post-consumer material, and that's vital: every item of post-consumer material is wrecked in a unique way that frustrates the glacial program of trial-and-error that Mother Nature relies on. *Pre-consumer* material, on the other hand, is wonderfully uniform, the perfect feedstock for Nature's lazy game of Russian roulette. By being identical and abundant, it presents a massive reservoir of free work waiting to be claimed by ~~freaks~~ the first individuals who are able to unlock it. [Answer] As a Sci-Fi idea, I think you are best off with nanobots designed to infiltrate, maintain and enhance neural pathways. In the future they'll be in the drinking water, much like fluoride today, as a public health measure. Perhaps they even patch genes, in order to fight cancer and other gene-based illnesses. Inevitably, they are released into the environment. If you have fish or squids the nano-bots would push them over the threshold to consciousness, and everything is possible from there. If you must start with single-cell organisms the path is less clear: The genetic enhancements would have to make changes leading to a multi-cellular organism. Conceivably, because the nanobots try to build and enhance neural pathways, this could be a "nerve-only" web of fibers in the water, of almost arbitrary size. Its cells would be the former microorganisms, living off oxygen and nutrients directly absorbed from the water, as before. A floating super brain. [Answer] # Symbiotic Medical Waste: My answer for this is similar for my answer to this question, [What would encourage multiple animal species to evolve human features simultaneously?](https://worldbuilding.stackexchange.com/questions/177004/what-would-encourage-multiple-animal-species-to-evolve-human-features-simultaneo/177011#177011). In that case, it was medical nanites. The waste would need to be very specialized and it would need to keep showing up. * As a side-note, most plastics can be broken down by webs of organisms into food. This does not allow them to become cyborgs, but may assist the ecosystem by being a constant supply of food to offset the harms from waste dumping. Your ecosystem is having the biomedical waste from a medical device company dumped into it - likely for generations. The liquid waste is anti-rejection drugs, while the solid waste is self-installing medical devices. The devices work (they are the rejects with tiny imperfections or prone to failures), and keep spontaneously implanting themselves into the fauna in the ecosystem. So now the animals in the environment are being implanted with random medical devices. Eventually, the species who are harmed by the devices will be selected against, while those that tolerate the devices survive. A few of the devices may even have some beneficial effect (like a pacemaker shocking predators, miniature artificial livers detoxifying the waste or hearing aids improving the hearing of the animals). Finally, the company dumping the waste develops self-repairing, self-replicating medical devices powered by the metabolism of the hosts. These are a financial disaster for the company (they repair themselves and cheap clients can get self-replicating copies) so the company pulls the line from the market and dumps them into your ecosystem. Now you have organisms who have adapted to the presence of medical devices AND devices that will spontaneously install and repair themselves in the organisms. The self-replicating programming of the devices gradually corrupts, and devices that "mutate" into useful devices for the animals replicate, while the devices that harm the survival of their "hosts" fail and are not replicated. Thus the machines and animals become functionally symbiotic. [Answer] 1. They use electrical components to shock people. A simple arrangement of two electrical components evolves a basic component to deliver an electrical shock. This is used to shock enemies, giving a major competitive advantage to any organism with such a modification. 2. They evolve components to communicate with each other. Extending on the existing adaptions to shock rivals, the organisms evolve a new configuration to add a small computing element to the arrangement, and send a signal to allies. 3. Communication slowly increases in complexity. Over numerous rounds of evolution they slowly incorporate more and more technology, gaining complicated methods of signalling each other, warning off rivals, mating. They slowly increase how many computer components they use, and increase the sophistication of proteins and RNA and lipids designed to interlink their components. 4. They incorporate a bus unit. Some very adaptible bus components which have some weak AI controls are inserted into an organism. The AI is extremely confused, but tries to organize the components according to its programming. The organisms already have extensive crosslinks between mechanical and artificial components, and the AI learns to program biology to increase compatibility and organize components. 5. They intermix technology. Numerous parallel evolutionary routes have evolved similar set ups, including different components. The organisms start crossbreeding and combining their bodies and machines according to the twisted desires of their DNA and the crude AIs, slowly increasing in complexity and power. [Answer] The current nature has some examples that could be used in analogy for technological waste. Example: Phyllobates vittatus This is a poison frog that gets its poison by eating certain insects. So if in your world, some critter found a particular waste useful, it could ingest it to benefit from its effects. This could be poison, but it could also be other kinds of benefits. Imagine you have some form of tiny batteries. A critter that digested those could develop methods to draw electrical power from them, to power some natural electric shock attacks. Or imagine something like "Chrysomallon squamiferum", a snail that digest sulfur compounds with the help of symbionts. Maybe the symbionts are technical in nature? (see <https://morethanadodo.com/2015/04/28/the-iron-snail/> for some of the strange details). It also splits of pyrite and iron from the food and puts it on its body, looking a bit like a knights horse armor. Or take some nautilus cephalopod and make it use microplastic to create its shell, because thats abundant. Adapting to be able to digest plastic contaminated food safely would be pretty nice for some lifeforms. Now take it one step further. Imagine your waste contains encapsulated sensor packages. Like a scintillation detector, that gives of flashes of light, when it encounters radiation. If those are abundant, organisms might incorporate them to achieve a radiation sense if it is useful. ]
[Question] [ I seek to have one of the setting's worlds be smaller than earth but is also conveniently earth-like in its gravity, 1g at the surface. A possible solution to this has been to have its core be made of osmium instead of iron and nickel, but I don't know how such a core would affect the rest of planet. My understanding of osmium is that it's rather toxic but whether that would bleed upwards and make the crust utterly inviable for life or have any other kinds of weirdness I'm uncertain. It can be assumed that the rest of the planet is made of more common/normal/expected materials with an earth-like atmosphere and with water content that has been adjusted to account for the smaller size of the planet. **How would a planet having an osmium core affect life living on it?** 'Life living on it' can also mean colonists trying to establish a colony should the osmium core make it unlikely life will ever naturally come about on it. [Answer] With an entire planetary core of osmium (even half of 5.9 \* 10^21 tons is an absurd amount), [diffusion](https://en.wikipedia.org/wiki/Molecular_diffusion), geological, and tectonic processes guarantee that large quantities of osmium compounds are present on the planetary crust and surface, much like compounds of the iron and nickel that make up the Earth's core are plentiful on the surface of the Earth. Note also that [osmium tetroxide](https://en.wikipedia.org/wiki/Osmium_tetroxide) forms by reaction of osmium with plain old oxygen, sublimes into a gas at room temperature, and is toxic in very small quantities. The "sublimation" part is important since any formed in the core or mantle will migrate towards the surface since a gas is less dense than the surrounding material and, along with that, anything that forms at the surface will stay in the atmosphere. Assuming an Earth-like nitrogen-oxygen mix in the atmosphere, the presence of significant quantities of this toxic gas seems probable. [Answer] I think the biggest impact will depend on whether osmium, at the temperature and pressure of the core the planet, would allow for the onset of a planetary magnetic field. Based on what we know, a planetary magnetic field helps protecting the planet atmosphere from depletion caused by the interaction with the stellar wind, which in turn will allow life to evolve (if the other conditions for this to happen are met). Basically it is the difference between Mars and Earth. Due to its high density, I doubt osmium would get in big quantities in the upper layers of the planet geological structure. [Answer] Short Answer: Because osmium reacts with oxygen to form the highly toxic osmium tetroxide, I substituted Iridim, which is almost as dense as osmium and much less toxic, in my calculations. Unfortunately, iridium is about as rare as osmium. A planet made of solid iridium with only a thin surface layer of other maderials would probably have too high a surface gravity for humans to tolerate. So it would not be suitable for humans or any beings used to Earth gravity to settle on. On the other hand, a planet with an oxygen rich atmosphere would need a high enough escape velocity to retain that oxygen for geologic eras of time. So I had to find online calculators for both the surface gravity and the escape velocity of planets I designed. I designed planets with varying abomunts of iridium in the core and materials with the same average density as Earth surrounding the core. That is a sort of an over simplification, but I figured If I could design a fairly plausible planet that way someone who is more expert in planetology could do more expert calculations. And of course a planet with a large amount of iridium is not very realistic. I designed a planet with iridium with 0.01 the mass of Earth and 0.0024467 the volume of Earth, and materials with the average density of Earth in 0.09 times the volume and mass of Earth, for a total mass of 0.1 of Earth and radius of 0.280497 Earth, or 1,787.0514 kilometers, and diameter of 2,574.1028 kilometers. That planet would have a surface gravity of 1.28 g and an escape velocity of 6.679 kilometers per second. Accepting the surface gravity limit of 1.25 to 1.5 g and the minimum escape velocity of 6.25 kilometers per second from *Habitable planets for Man* Stephen H. Dole, 1964, <https://www.rand.org/content/dam/rand/pubs/commercial_books/2007/RAND_CB179-1.pdf> I decided that the surface gravity of 1.28 g was a little high but acceptable and the escape velocity of 6.679 kilometers per second was on the low end but acceptable. Anywone who wants to calculate a planet with a lower surface gravity and a higher escape velocity can try it. Long Answer: Here is a link to a question, and its answers, including mine: <https://astronomy.stackexchange.com/questions/41590/can-a-habitable-planet-be-smaller-than-0-58-earth-radii/41599#41599> You will note that PM 2Ring's comment to my answer there suggests using another heavy element as the planet's core. > > Can we switch from osmium to iridium? ;) They have almost the same density (depending on the crystallisation state), but osmium is nasty stuff. Its oxide is quite toxic and rather volatile, whereas iridium is fairly inert > > > Since GrumpyYoungMan's answer here says that osmium would react with the common element oxygen to form a poisonous gas, osmium tetroxide, which would seep upward from the core of the planet and poison life, iridium seems like a better alternative to Osmium. > > The measured density of iridium is only slightly lower (by about 0.12%) than that of osmium, the densest metal known.[11][12] Some ambiguity occurred regarding which of the two elements was denser, due to the small size of the difference in density and difficulties in measuring it accurately,[13] but, with increased accuracy in factors used for calculating density, X-ray crystallographic data yielded densities of 22.56 g/cm3 for iridium and 22.59 g/cm3 for osmium.[14] > > > <https://en.wikipedia.org/wiki/Iridium> Unfortunately Iridium is about as rare as osmium, making planets with large amounts of iridium about as impossible to form naturally as those with Osmium, and about as difficult for an advanced civilization to build. The planet Earth has an average density of 5.513 grams per cubic centimeter (which of course is partially the result of gravitational compression of matter deep in its interior) while Iridium has a density of 22.56 grams per cubitc centimeter. That is 4.0921458 times the average density of Earth. In my answer at <https://astronomy.stackexchange.com/questions/41590/can-a-habitable-planet-be-smaller-than-0-58-earth-radii/41599#41599> I quoted from a source which gives minimum masses for habitable planets calculated various ways as 0.1 Earth mass, 0.i2 Earth mass, and 0.23 Earth mass. The authors concluded that worlds with 0.25 Earth mass are at about the lowest possible mass for habitable worlds, though various factors could drive the limit up or down in specific cases. So in my answer I caculated the radii of planets which were almost entirely made of osmium and had masses of 0.1 and 0.25 that of Earth. But iridium would not be nearly as toxic as osmium. So a hypothetical iridium planet with 0.1 times the mass of Earth would have a volume which was 0.1 times that of Earth divided by 4.0921458, and a hypothetical iridium planet with a mass of 0.25 Earth mass would have a volume which was 0.25 times the volume of earth, divided by 4.0921458. Thus a 0.1 Earth mass planet would have 0.024437 times the volume of Earth, and thus 0.180019587 times the radius of Earth, and a 0.25 Earth mass planet would have 0.061926 times the volume of Earth, and thus 0.245430278 the radius of Earth. So a hypothetical iridium planet with 0.1 times the mass of Earth would have a radius of about 1,146.9042 kilometers, and diameter of about 2,293.8084 kilometers, while a hypothetical iridium planet with 0.25 times the mass of Earth would have a radius of about 1,592.75 kilometers, and diameter of about 3,185.5 kilometers. The hypothetical Iridium planet with mass of 0.1 Earth would have a surface gravity of 3.09 Earth gravity or g, and an escape velocity of 8.337 kilometers per second. The hypothetical Iridium planet with mass of 0.25 Earth would have a surface gravity of 4.01 g, and an escape velocity of 11.29 kilometers per second. <https://philip-p-ide.uk/doku.php/blog/articles/software/surface_gravity_calc> <https://www.omnicalculator.com/physics/escape-velocity> Those escape velocities should be sufficient to retain a oxygen nitrogen atmosphere in case a writer wants to make the planet habitable for humans. But the surface gravities would be too high for humans to endure for more than minutes or hours. Humans would never colonize such planets or visit them for long without anti gravity, nor would human like intelligent beings evolve on them. However, native plants and land animals should have no trouble evolving adaptions to the high surface gravity, and thus native intelligent beings shaped like centaurs, elephants, catapillars, etc. should manage to evolve on a hypothetical irridum planet with a relatively thin layar of more common elements necessary for life. Let's try a planet with 0.05 Earth mass in Iridium and 0.2 Earth mass in stuff with the same average density as Earth. The irridium core would have 0.05 times the volume of Earth divided by 4.0921458, or 0.0122185 the volume of Earth while the other 0.2 of Earth's mass would have 0.2 of Earth's volume. so the total would be 0.2122185 of Earth's volume. Such a sphere would have 0.3700 the radius of Earth, or a radius of 2,357.27 kilometers and diameter of 4,714.54 kilometers. and it would have a surface gravity of 1.83 g and an escape velocity of 9.195 kilometers per second. The surface gravity would still be too high. Suppose that the planet had 0.05 of Earth's mass in iridium and 0.25 Earth's mass in lighter elements with the same density as the Earth. The irridium core would have 0.05 times the volume of Earth divided by 4.0921458, or 0.0122185 the volume of Earth while the other 0.25 of Earth's mass would have 0.25 of Earth's volume. so the total would be 0.2622185 of Earth's volume. The planet would have a radius of 0.39706 Earth's radius, or 2,529.6692 kilometers, and a diameter of 5,059.3384 kilometers. It would have a surface gravity of 1.91 g and an escape velocity of 9.723 kilometers per second. Suppose the planet has 0.025 of Earth's mass in Irridium and 0.275 of Earth's mass in materials with Earth's average density. The irridium core would have 0.025 times the volume of Earth divided by 4.0921458, or 0.0061092 the volume of Earth while the other 0.275 of Earth's mass would have 0.275 of Earth's volume. so the total would be 0.2811092 of Earth's volume. The planet would have a radius of 0.4063 of Earth's radius, or 2,588.5373 kilometers, and a diameter of 5,177.0746 kilometers. It would have a surface gravity of 1.82 g and an escape velocity of 9.612 kilometers per second. Suppose that the planet has 0.01 of Earth's mass in iridium and and 0.29 of Earth's mass in materials with Earth's average density. The irridium core would have 0.01 times the volume of Earth divided by 4.0921458, or 0.0024437 the volume of Earth while the other 0.29 of Earth's mass would have 0.29 of Earth's volume. so the total would be 0.2924437 of Earth's volume. So the planet's radius would be 0.417766698 of Earth's radius, or 2,661.591 kilometers, and the diameter would be 5,323.182 kilometers. The surface gravity would be 1.72 g and the escape velocity would be 9.48 kilometers per second. Suppose that the planet has 0.01 of Earth's mass in iridium and and 0.39 of Earth's mass in materials with Earth's average density. The irridium core would have 0.01 times the volume of Earth divided by 4.0921458, or 0.0024437 the volume of Earth while the other 0.39 of Earth's mass would have 0.39 of Earth's volume. so the total would be 0.3924437 of Earth's volume. So the planet's radius would be 0.45418165 Earth's radius, or 2,893.5909 kilometers, and the diameter would be 5,787.1818 kilometers. The surface gravity would be 1.94 g and the escape velocity would be 9.01 kilometers per second. After some more calculations, I tried a planet with 0.01 Earth mass in iridium and 0.04 Earth mass in substances with the average density of earth, for a totalof 0.05 Earth mass and 0.0424437 Earth's volume. Such a world would have a radius of 0.228539075 Earth radius, or 1,4560219 kilometers, and a diameter of 2,512.0438 kilometers. And it would have a surface gravity of 0.96 g, and an escape velocity of 5.232 kilometers per second. The surface gravity would be great, very close to Earth's, but the escape velocity would be a bit too low, oging by the minimum of 6.25 kilometers per second in *Habitable Planets for Man*, Stephen H. Dole, 1964. So the next design I tried was a planet with 0.01 Earth mass in iridium with a volume of 0.0024437 of Earth's volume, and a mass of 0.09 earth mass in material with the average density of Earth. That planet would have 0.1 times the mass of Earth and 0.0924437 the volume of Earth. It would have 0.280497872 the radius of Earth, 1,787.0514 kilometers, and a diameter of 2,574.1028 kilometers. It would have a surface gravity of 1.28 gravity, which is more or less within acceptable limits, and an escape velocity of 6.679 kilommeters per second,w hich should b ehigh enough to be acceptable. And no doubt trying different figures can come up with a planet with a lower surface gravity and a higher escape velocity. [Answer] **The core of a planet is so deep it's hard to imagine it having an impact on life** With any terrestrial planet, the structure will be that there is the crust, the mantle, a molten outer core, and a solid inner core. The mantle can be divided into the upper and lower mantle. The lower mantle is about 670 kilometers before the Earth's surface. The molten outer core is about 2900 km below the Earth's surface, and the inner core is 5100 km below the Earth's surface. So let's assume this fictional planet has a core made almost entirely of osmium. That inner core is surrounded by a massive layer of molten rock (the outer core), which is surrounded by layers of solid rock (the mantle). Then all that is wrapped up by the Earth's crust, and somewhere at the very outermost layer of the Earth's surface, you have the soil where all the animals and plants reside. My point is that a core is surrounded by so other material that its composition probably doesn't matter at the end of the day. Even if the core is made of osmium, it's not as if said osmium is just going to bleed towards the surface. It's too deep. If the gravity was allowed to be different from the Earth I might have suggested that a denser core might lead to a change, but you mentioned this planet has the exact same gravity as Earth, and I'd assume a slight change in composition wouldn't lead to a significant change in mass anyways. I think it's safe to say life would not face any issues or major changes if the composition of the core changed to osmium. ]
[Question] [ The vegetable lamb is a plant that has a sheep for fruit. These sheep are quite similar to natural sheep, with legs, guts, and wool in the same anatomy as a sheep, and are attached to the rest of the plant through the umbilicus. The sheep are capable of movement and digestion similarly to a regular sheep What seed-dispersal method would such a plant be likely to use? [Answer] ***What seed-dispersal method would such a plant be likely to use?*** For the sheep-fruit? none. The umbilical will simply snap & the 'sheep' drop off the plant right there & walk away. For it's seeds to propagate itself? the sheep-fruits' legs, they *'are'* the dispersal method. The sheep-fruit would just wander off grazing as sheep are wont to do. Seeds of the plant are grown in the sheep-fruit & deposited with its dung as it wanders & grazes. *It's likely the sheep-fruit don't propagate 'themselves' directly but only indirectly through propagation of the plant species they fruited from, they'll be part of the life cycle of the plant & vice-versa, they will **be** it's seed dispersal method, the seeds grow in the sheep-fruits womb-analogue & are 'birthed' as it poops to insure a little parcel of fertiliser for the seeds, all the sheep-fruit will be ewes, there will be no rams, if the sheep fruit aren't integral to the plants actual means of propagation & seed dispersal then however they came to be (genetic engineering?) they're just dead weight evolutionarily speaking that will be heavily selected against & eventually disappear without constant intervention.* *To keep them looking like ordinary sheep constant intervention by selective breeding will probably be required, harvesting (culling?) of immature sheep-fruit with any variation from the norm while still on the vine or otherwise immature (unripe?), before they're reproductively mature, is probably needed.* [Answer] [Dandelion](https://en.wikipedia.org/wiki/Taraxacum) or [thistle](https://en.wikipedia.org/wiki/Thistle) style aerial dispersion with wool as the sail. Seeds will grow on the skin of the sheep fruit like they do on a [strawberry](https://en.wikipedia.org/wiki/Strawberry) with some of the wool of the sheep growing out of the seeds. When the seeds mature the connective tissue between the seed and the skin weakens and the seeds are pulled off into the wind and go wherever it takes them. This method is haphazard and a lot of seed that will never find fertile ground but it does work. Since a single sheep has a lot of surface area for seed production compared to a dandelion the numbers are definitely going to be in the plants' favour. [Answer] @Pelinore suggests all sheep-fruits are ewes, but there's another answer: ## All the sheep-fruits are rams. *Strong, good looking rams*. Once mature, they wander off into the world in search for willing ewes. (Coincidentally, the reproductive cycle of the sheep plant is synch with that of the sheep.) If an ewe is charmed and mates with a sheep-fruit, the "offspring" growing in her will not be an ordinary lamb, but a lamb-sized seed. The large seeds offer a great advantage to the plants, as all the energy supplied by the mother ewe lets the tree sprout in environments where other plants have a very hard time surviving. The evolutinary path that led to the sheep-fruit plant is somewhat unclear, but the currently most widely accepted hypothesis is that the seeds of it's ancestors were similar to those of the [burdock](https://en.wikipedia.org/wiki/Arctium), and would spread by sticking to passing animals. I'd like to think the seeds are born peacefully with no lasting harm done to its mother, except the confusion and possible emotional scars, but you could adjust this to whatever level of macabre you prefer. [Answer] ## Sheep are fruit, dragons are your dispersal method. the sheep keep the area around the plant clear of competition while they develop, eating every other plant within reach. They act as fruit when predators kill and eat the sheep. the sheep will have to have seeds dispersed throughout its body, which will be deposited in predator dung. Your problem is the dispersal will be much more effective if the umbilical simply withers and the sheep runs away as Pelinore suggests. **How other fantasy creature can make this work better.** This works a lot better if there are flying predators large enough to eat the sheep in a single bite (dragons, wyvern, griffin, ect), in which case the sheep contains only one or two very large seed which gets dropped in the predator dung, but since it is a flying predator it will have a large range and this the seed gets dropped a long distance away. This works even better in areas with lots of islands or mountains where the sheep physically walking will not be able to travel too far. You might even have predators that evolve to feed mostly on the vegetable sheep and thus will need a huge range to find enough of them, since they can't grow new sheep very fast. ]
[Question] [ Trying to work up a race of creatures that resemble humans just taller, more muscular, and preferably, able to fit through doors. I just can't put my finger on how much they should weigh. [Answer] **ROBERT WADLOW, 8 ft 11.1 in** You can easily use a real-life example as a reference point, [ROBERT WADLOW, is 8 ft 11.1 in](https://www.guinnessworldrecords.com/world-records/tallest-man-ever), almost equal to what you want and Robert's greatest recorded weight was **222.71 kg (35 st 1l b)** on his 21st birthday and he weighed 199 kg (31 st 5 lb) at the time of his death. You can put up an approx estimate of around 230 - 250 KGs, for a healthy giant. [Answer] Something more specific than L.Dutch's application of the square-cube law is the [new BMI formula](https://en.wikipedia.org/wiki/Body_mass_index#Proposed_new_BMI): > > ([HEIGHT METERS] ^ 2.5) \* [BMI] / 1.3 = [WEIGHT KG] > > > For instance, let's say they have a BMI of 23 and a height of 9 feet: > > 30.48 centimeters to a foot > > > 30.48 \* 9 = 274.32 centimeters tall > > > 274.32 / 100 = 2.7432 meters tall > > > 2.7432 ^ 2.5 = 12.4636051005 > > > 12.4636051005 / 1.3 = 9.58738853885 > > > 9.58738853885 \* 23 = 220.509936394 kilograms, or 486.1411941166471 pounds. > > > It works for normal humans as well as it does for 9-foot giants; let's take one with a BMI of 23 and a height of 5.75 feet: > > 30.48 centimeters to a foot > > > 30.48 \* 5.75 = 175.26 centimeters tall > > > 175.26 / 100 = 1.7526 meters tall > > > 1.7526 ^ 2.5 = 4.06637117725 > > > 12.4636051005 / 1.3 = 3.12797782865 > > > 3.12797782865 \* 23 = 71.943490059 kilograms, or 158.608245678824 pounds. > > > That fits in pretty well on [this here BMI chart](https://en.wikipedia.org/wiki/Body_mass_index#/media/File:BMI_chart.png). [Answer] **Taller and more muscular!** Instead of these mathematic ideals and abstractions, let us consider a real life sometime-biped much like myself - robustly built. [![bear](https://i.stack.imgur.com/St9eq.jpg)](https://i.stack.imgur.com/St9eq.jpg) <https://unofficialnetworks.com/2021/08/19/fat-bear-brooks-falls/> This muscular grizzly bear is probably a little over 8 feet and was estimated to weigh 1400 pounds which is a nice 100 stone. That is 2.44 meters and 635 kg for you moderns. [Answer] Use the good old square cube law. Weight is proportional to the volume of a body, thus the cube of the length. If your creatures are X times the length of your reference sample, a good first approximation of their weight, all the rest being the same, is $X^3$. To give you a numerical example, if they were 2 times as tall as a human, they would weigh $2^3=8$ times as much. ]
[Question] [ I was thinking of an alternate history, in a part of a civilization, living along the Eastern Mediterranean, during the Bronze Age moves to the sea floor to found an underwater civilization. They build underwater homes on the sea floor, and use buckets to transport air from the surface of the Mediterranean to their underwater homes. They use sand to desalinate the water to drink. Over several thousand years this underwater civilization spreads throughout the Mediterranean and beyond. Would this underwater civilization be possible during the Bronze Age? If so what would be the best way for the members of this civilization to bring air to breath when traveling underwater? [Answer] > > Would this underwater civilization be possible during the Bronze Age? > > > No. First thing off: > > They use sand to desalinate the water to drink. > > > Sand might be good at filtering out particles suspended in water. But salt is present in water as a solution, sand does nothing to it. Else every beach would be as good as a fresh water lake. > > They build underwater homes on the sea floor > > > Also this doesn't stand: first, lack of materials and technologies to build an underwater dome, second and even more important, how do you keep a fire in an underwater environment with no air recirculation? > > they use buckets to transport air from the surface of the Mediterranean to their underwater homes > > > To pull underwater a 10 liter bucket you need to pull 100 N, or 10 kg: without proper ballast and swimming equipment it's an hassle, believe me. And that would be the air you would use with just about 5 breaths. Lacking other method, this one is absolutely inefficient. [Answer] Wouldn't it make more sense if they just migrated to a tunnel network that was underground but had sea access. As in tunnels that terminate at caves and those caves have pools in them with flooded tunnels leading out to the sea. Then perhaps your people could develop something like a breathing helmet made of leather sealed with pitch or resin or similar allowing them to move through the tunnels. They wont be able to see of course but then without a waterproof light source things are going to be pretty dark in those underwater tunnels anyway. Over time the tunnels have ropes attached to them so that people can pull themselves to where they need to be or even pulleys so that things can be transported. They could have breathing helmets placed in various places for emergency use including for people diving from the sea surface to use to escape into the tunnel network. If the helmets are tethered with the open end down then the air should remain inside. Such a civilisation could engage in piracy along the coast. Sneak onto ships at night, steal what they need then dive overboard with their loot, escaping by diving down to the caves. The local merchants blame it on mermaids or somesuch, legends of people riding dolphins and then disappearing under the waves. Similar legends exist on land but only rural people believe them, mysterious spirits that rise from the underworld to prey on the living. Most people guard their doors when such beings are spotted, none dare follow them back to the underworld. [Answer] Nope... Air is the biggest issue along with water tight buildings. Believe it or not, but water is very good at eroding away at materials and there would be no way to manually transfer enough air down underwater (its like trying to scuba dive but you have to go up and get air each time). You would also have issues with the sand, as overtime salt will accumulate in the sand and you will need to source sand from somewhere where there is no salt which means going above ground or into fresh water rivers and transporting truck loads manually. It would also need to be isolated from the salt water until you are ready to use it as a filter. Now disregarding the housing material you will use to build this (because I have no idea) I think the best way would to have some sort of special oxygen producing plant (like it produces visible bubbles worth of air). You could then build your houses as domes above these plants or integrate them into the walls of your plants to provide you with oxygen. (you would need something to remove excess air to make room, so many some special valve or tubing could be designed to accommodate this like in a toilet) I would also adjust the biology of your people so that they can actually drink salt water. This would solve the huge issue of gathering and storing fresh water while you are already underwater. ]
[Question] [ Culture is heavily influenced by the Mass Media. Social changes are tailored to reflect what humans think is “sexy” or “appealing”. Media influences us on what the ideal body is to the style of clothing we wear. The process of becoming “beautiful” varies with each different country from how we apply makeup to achieving the ideal body type. All of this plays into the products we buy or consume to achieve this look. In this world, humans are similar to us except for a few minor differences, one of which being that they have a mating season. This breeding period lasts for about three months of the year, during which time a male or female is receptive to mating. Throughout the rest of the year, both parties are generally uninterested in sex. Would it be possible to market beauty products to this species under these circumstances? [Answer] # Either one of two things is true: 1. **Each individual has his/her own breeding season**. In that case, if these seasons do not overlap, then you have potential customers all year long. So you just advertise all year long. 2. **There is one breeding season**. Then, culturally, this is a very important special time of year. There is increased money spent on advertising, and many products are targeted to be sold only this time of year. The market for beauty products spikes during these few months. Hmmm....if only there was a retail shopping phenomenon in the US and Western Europe that was like this... [![enter image description here](https://i.stack.imgur.com/hFYKt.png)](https://i.stack.imgur.com/hFYKt.png) # Breeding season is Christmas for beauty products Here in the real world, we already see the overall internet retail sails nearly double for two months out of the year. I'm sure if I investigated some specific categories of goods, you might see up to 50% of sales driven by just those two months. So, whatever tactics you use to sell things during Christmas in the West, you would use to sell beauty products to the horny near-estrous of your species. [Answer] ## There are more reasons for improving your appearance than just finding a mate I don't know much about the sociology of your aliens. But for humans, physical attractiveness has many more advantages. * It makes one appear subconsciously more trustworthy * It makes one appear stronger and healthier * It suggests social status * It improves one's self-esteem That's why beauty products are also popular with people who are not actively looking for a mate or when they are in a context where it would be inappropriate to do so (like in a business context). [Answer] Same way you market seasonal products here on Earth. Breeding period may be shorter - but then these species would be preparing for it in advance, like here we do for the beach in summer and skiing in winter. If breeding season is random for all individuals, then some segment of population would be interested in those products throughout the year. [Answer] Yes... we already market the crap out of everything... Christmas, Black Friday, Thanksgiving, Halloween, Easter, Valentines day, New years... Summer, Winter, Autumn, Spring. Independence Day, Queens birthday, Labor Day... Super bowl, Olympics, Fifa, 9/11, World War 2 memorials, etc etc etc If you want to go into beauty or mating related products, we have a even larger amount that we market all year around, but in your case, it would probably be advertised roughly 3-4 months ahead of time and build up more and more as the season approaches. We already have many products which are targeted at making you more attractive and desirable to the opposite sex. The biggest things are probable Perfumes/Deoderants/Colonge and make up. Some other things include: * Shoes * Underwear * Shirts, dresses, skirts, pants, shorts, singlets, clothes in general * Scarves * Hates * Glasses * Razors * Straight Teeth * White teeth * Body shape and weight * Food and Diets * Proteins for those sick gains * Gym/Sports and the related gear * Doritos Just take any one of those, and you can find a variety of different advertisements. Which goes to show that we can market anything as a way to get laid. ]
[Question] [ This is loosely linked to my [nature Mage](https://worldbuilding.stackexchange.com/questions/12801/how-to-defeat-a-nature-mage) questions. In my fantasy world I want a race of Orcs. These are the characteristics they have to have: * Stand between 6 and 7 feet tall * Have crude weapons * Reproduce quickly * Reach Sexual maturity at age five and mental maturity at age 15 * Live a maximum of 25 years * Have mindset of 15 year old human children * unable to wield magic How fast would the cells of these orcs have to grow and divide to reach these growth rates and reduce mental capacity to that of a fifteen year old human child? How realistic would this be to a reader? Note that while there is magic in my world, I want a little handwavium used here as possible. Please try to include known biological processes and cell growth rates as a basis for your answer. [Answer] **These are all just fine.** > > Stand between 6 and 7 feet tall > > > Just feed them well, this is not far off from human average height. Nothing magical required. > > Have crude weapons > > > Ok, well they're basically 15 year old human children. Crude weapons is all they can make. > > Reproduce quickly & reach sexual maturity at age five > > > Reproducing quickly will be a result of sexual maturity at five years old. Reaching sexual maturity that soon for a humanoid is not unfathomable, but being physically developed enough to actually bear children is the main problem. Hormonal changes could conceivably allow a human to achieve this, so it's not too unlikely for an orc. > > [Reach] mental maturity at age 15 > > > This is rather quick compared to most humans, but considering this is old enough to be a great-grandfather and the general hard-knock life of an orc, it's not unlikely. > > Live a maximum of 25 years > > > If you had a great-great-great grandfather still kicking around you'd probably think it was about time he went off to meet Gruumsh. Orcs aren't a civilized society, this maximum age would be easily believable. > > Have mindset of 15 year old human children > > > Again, see many humans alive today. Additionally as this would be older than the average age for the orcs, it's easily believed. > > unable to wield magic > > > I can't wield magic, I wouldn't be surprised to learn another creature can't either. [Answer] almost all of this is trivial to say "they just evolved that way". Species of all kinds of intellectual levels have evolved, with different lifespans and sexual maturity. For the most part you can get away with saying "they are just that way". The only real world building issue I could fight over is the intellect levels vs tools. 15 year olds are sometimes rather emotionally immature, but they aren't idiots. a 15 year old can make far better then 'crude tools' himself, I've seen some really skilled 15 year olds. Once taught how to do something they can do it pretty well, and it only takes one smart 15 year old to figure out how to do something. Plus, if they live around smarter humans they just have to be taught by smarter people how to make better tools and then remember. In short, a race of 15 year olds should have more then 'crude tools'. Bonobos have crude tools, bonobos raised by humans can cook meals over fire or on a stove, work light switches and even touchpads, and generally interact with the tools we provide them pretty well. If you make a species much smarter then bonobos your have to put more thought into how their intellect vs their tools interact to avoid the, all to common in fantasy, mistake of making 'primative' tribes that are too smart to continue living so primitively. In particular if your orcs are near humans or other intelligent races they will be getting tech and ideas from those. Even if they are not smart enough to create they can be smart enough to *USE* it. You could have them be smart and their lack of tools is simply due to lack of resources to build or make them, the same way that third world countries still rely on 'primitive' hunting techniques for food because, even though anyone can tell them how to build advanced guns, they still don't have resources to make, craft, and maintain a large number of them. This would be the easiest approach to explain the tool vs intellect dependency. However, then you need to explain *why* they have limited resources, and why they don't just trade with, or raid, nearby humans for their goods. Alternatively you can make them actually less intelligent, with actual cognitive limitations preventing understanding the use of advanced tools. However, if you do that your want to put some real thought into how to make culture and technology equivalent to their actual intellect. In particular avoid trying to say "their just like us humans, but stupid". They won't be able to have the same sort of conversations and philosophies as humans if they are less intelligent, this would also effect culture and beliefs and many things. Their cognitive difference will result in a very different species then humans. This is worth it's own separate world building question actually, development of culture and technology for a cognitively limited sapient species. *IF* you want to go with hard science approach I could nitpick on some other minor details, though I think they are all small enough that you could be forgiven for taking poetic license on them. The rest is major nitpick and your welcome to skip it!!!! First, sexual and mental maturity are awfully far away. Sexual and mental maturity should be closer together. Humans are much closer when it comes to our mental and sexual maturity. We may consider 20 to be be 'adult' now of days, but we have developed most of our mental abilities long before that, we have room to *learn* more, were always learning, but our cognitive abilities are mostly complete at a much closer age. Besides, if we reach sexual maturity around 10 then we would have to reach mental maturity at 30 to keep with your ratio. Related to issue of sexual maturity: For orcs to evolve intellect they would need to be heavily K selected species. K select species don't tend to reach maturity at such a young age anyways. Look at most other primates. Bonobo reach sexual maturity at age 9, and their err...sexual lifestyle would encourage quick sexual maturity. Chimps reach sexual maturity after humans. It's the same for nearly all 'intelligent' animals, they have long childhoods, and these creatures are all less intelligent, and smaller, then your orcs. There are many reasons for this, the short version is that intelligence means less instincts, you need to *learn* how to use your intellect to survive. You won't survive on your own until you have learned, and so you need parental investment much longer which generally means delayed sexual maturity. This is only one part of it, all K select species have delayed sexual maturity and sapient practically necessitates K select strategy. Your orcs are also much larger then the other intelligent animals. The larger a species is the longer it takes to reach sexual maturity in general. In short for sexual maturity to be realistic I would push it back to closer to us, 8-10 lets say. I would also say that the males at least must wait much longer before able to compete sexually for females. Rather or not the females begin to reproduce as soon as they reach maturity depends on your society, but most likely they would if your assuming a less intelligent species then humans. Lower intellect means their less likely to have complex cultures which would discourage female from reproducing 'too soon'. If you really want reproduction at a young age It could be done, but only with selective pressures. Maybe carrying a child to term is difficult enough that they start reproducing early to have more years of trying to conceive, with parents helping to care for grandchildren when their children are not yet ready to care for the child. However, your need either **very** high infant mortality (but very low death in childbirth), or simple difficulty with conception or carrying to term to make this work; along with grandparent investment being more common then most animals. Of course grandparent investment would in turn place evolutionary pressures to encourage more intellect to evolve in the orcs technically; but maybe they *are* evolving to greater intellect and just haven't gotten to our level yet. However, these are both nitpicks from someone who really likes considering evolution. I'm pretty sure you could ignore most of this and have few, if any, complain. I would not scream in outrage if you had your orcs as you described with little further justification. So long as you don't also make them [always chaotic evil](http://tvtropes.org/pmwiki/pmwiki.php/Main/AlwaysChaoticEvil) that is :) ]
[Question] [ Joe has a special ability where everyone always believes whatever he says. For example, if Joe says "the sky is black" then everyone believes that the sky is black. If Joe says "1+1=3" then everyone believes it. Note that this doesn't just change their affirmations of what is real, it also changes their thoughts and senses. If Joe says the sky is black, everyone will *see* a black sky. Similarly, if Joe says 1+1=3 then any set of 2 items will appear to be 3 items. It's kind of like programming. With the invention of chat gpt there has been an increase in interest in "text injection hacks/prompt hijacking." This made me think, what if everyone had to do/think/believe everything, no matter what, that someone (or people in general) said. The basic situation of my world is that text/language can reshape reality. The problem is that illogical and nonsensical commands can be formed from any language. In English, for example, if someone says "a circle is a square that gulps water to fart" then reality has to obey, and that would be an issue. Also, there is nothing to stop one angry lunatic from saying "everything got blown up in an inferno" and ending reality. Then of course, there is the issue of if someone says/writes jjjienmjdk88nug. Since reality has to obey text data, then reality would have to make that happen, but "that" doesn't mean anything meaningful. How can I reconcile a world where whatever is written down becomes true with a world that doesn't fall apart in an instant? [Answer] ## Forget about consistency There is no way that a world that must make everything that is noted true has any internal consistency. Think about the following statement getting written down: * Yesterday, every human, including me, died. The result is, that the day *before* all humans died. But then nobody could have written the statement! We are in on the deep end of Paradox, and there is literally no way to resolve those *and* keep an internal consistency. We pretty much have the [time-machine-wars Redux](https://worldbuilding.stackexchange.com/questions/168795/can-a-world-where-everyone-has-a-time-machine-be-consistent/168803#168803): everybody loses and wins at the same time: the idea of a single reality existing stops being a thing the moment the first time machine activates and the sheer idea or reality becomes a theoretical construct. Everybody creates their own world by writing stuff down. [Answer] *Note: This answer was written before the question was changed to state that language truly affects objective reality. As written, the new question does not leave any room to resolve the inconsistencies and paradoxes that are a necessary consequence. I leave my original answer to explore an alternative approach that still allows for a consistent and functional world.* ## Reality does not actually change, just peoples' perception of it The question actually describes two different scenarios: > > Joe has a special ability where everyone always believes whatever he says > > > and > > The basic situation of my world is that text/language can reshape reality. > > > As others have pointed out, the second scenario is quite problematic, easily leading to inconsistencies and paradoxes. However, if text (written or spoken) only alters peoples' perception of reality, this is much easier to handle. If Joe tells me "That fire is refreshingly cold.", I might not even notice my hand burning to a crisp - and neither would anyone else who heard Joe. Problems with nonsensical instructions could easily be handled by having the effect be subject to the reader's or listener's interpretation - whenever Joe says or writes something, peoples' perception of reality changes to what they believe the sentence to mean. If they don't understand it, or believe that it doesn't mean anything at all, nothing happens. This works even if the power is not limited to Joe, but affects all text. In that case, language would become an incredibly powerful weapon. Likely, earmuffs and blurring glasses would be commonplace to avoid both targeted and accidental exposure to harmful text. People would carry around easily accessible emergency sentences affirming their identity as well as the main aspects of reality. Paramedics would be schooled to provide first-text-aid in the form of carefully crafted sentences intended to undo harmful effects. * "You are a human being." * "Your eyes perceive light that falls into them and nothing else." * "Your ears hear vibrations in the air, and nothing else." * "You remember things that happened to you, and nothing else." Laws would handle harmful use of language just as they currently deal with other deadly weapons - potentially even in the form of self-executing if-then rules that people are regularly forced to read, with subclauses ensuring that they don't overwrite the conditions with their own sentences. Since communication is still incredibly important, conventions would arise to ensure that people do not accidentally alter each others' perceptions. Non-verbal communication would be commonplace, with guard clauses (e.g. "Nothing in the next sentence will affect your perception of reality.", shortened in practice to "Non-altering") being used wherever non-verbal communication is not possible. [Answer] # Old Text Overrides New Text This allows precautions against future disaster, as well as adaptations as new threats are discovered. But those threats must be intelligently addressed in the moment, allowing for fun storytelling. Imagine that it works as a living document like the constitution. Perhaps early on, after averting a catastrophe, Joe lays down some **sturdy ground rules**. However, they can't be *too* sturdy if Joe wants to have any fun! How do you implement such a rule? Joe writes it down! Here are some examples of his rules: * Old text overrides new text. * The world can't fall apart in an instant. *(Delightfully vague enough to allow multiple interpretations, almost completely solving your problem in one sentence!)* * Text can't cause paradoxes. *(Spacetime is secure, and unfortunately BBC has to cancel Doctor Who)* * To reshape reality, text must be meaningful in the author's native language. *(Phew, now "jjjienmjdk88nug" doesn't melt everything, and a babbling toddler can't accidentally cause a disaster in ancient egyptian)* * Everything is itself. *(This avoids some **[Baba is You](https://en.wikipedia.org/wiki/Baba_Is_You)**-style horror scenarios)* * Humans can't be directly physically hurt by text. *(No nasty violence, thanks. May also solve papercuts)* This is just a fun idea, but I imagine that at the end of the story, the only way to defeat the villain is for Joe to give up his power by writing "After this sentence, text can't reshape reality." Then he erases the period and adds "...except to make ice cream." [Answer] There is no way to accomplish what you speak of in terms of altering reality generally merely by speaking or writing *potentially nonsensical or mutually contrary things*, since it would introduce inconsistency, contradicting the very nature of reality. What can be altered is people's **perceptions** of reality, and in so many ways, we are already there. Perceptions have no requirement of being internally consistent, so illusions can be perpetuated for as long as the gullibility of the audience lasts, which in many cases may be forever. Well, actually, building somewhat on [Nepene's answer](https://worldbuilding.stackexchange.com/a/246436/22589), there *is* a way to have a being that alters reality by speaking--but this being would have to be perfectly consistent, rigorous, and self-disciplined. This includes being omniscient about cause and effect, even about those consequences that would ordinarily be unintended, so as to prevent contradiction. In short **this Being would have to be God**. Of course, this does not necessarily change people's perceptions, since people's perceptions are unhinged and sometimes completely unrelated to reality. So the two transformations--of reality on the one hand, and of people's perceptions on the other hand--can occur largely independent of one another. [Answer] # All orders are carried out by omnipotent but not omniscient helper angels/spirits Reality is run by very powerful and eager to serve spirits/ angels which will carry out whatever written command. They do not have infinite creativity, and if you make nonsensical commands they can't carry them out. # Past people have locked down key functions. Key functions, like the nature of numbers and shapes and the world in general are locked out of the control of most people. Older and more powerful people with better access have written stuff like "Only those with metatron permissions or above can modify the geometry of shapes and if you try you'll be timeline wiped" and if you try to change that you'll be erased from the timeline before you can try. Cities and settlements have also established elaborate networks of written commands to stop anyone from causing too much damage. [Answer] For a world to be consistent when the observed laws of physics can change basically on demand, there would still need to be a set of laws that define how this power can, and more importantly can't, act on the world. Were it that any one person can change the world for everybody, then reality would essentially just be a chaotic mess and life would likely die as it it would only take one person to end it all by stating that there is no atmosphere or something and killing everyone. As such, what is needed is a set of rules that would keep the world in a somewhat consistent state even as several being are basically trying to twist reality with their words. Warning: Twisting reality with your beliefs can be dangerous. Take care to avoid the strangely unaffected high school student and more importantly his right arm. And whatever you do, don't believe that the kid is a monster -- it will not end well for you. ## The World "Computer" Looking at the universe from a programming perspective, pretend that it stems from the base class of Plane. The Universe object has a set of parameters that defines its physical constants. Declare the Universe object with the proper parameters, and boom -- the universe was created. This will make a lot of people very angry and will widely be regarded as a bad move. References aside, there's more to declare. The celestial objects -- stars and planets may be their own objects derived from the Universe object. From there, a Planet may have Life, and Life can extend into say Human. Each Human is its own object with its own set of parameters and processes. Basically, Object-Oriented Programming, but for the universe. Your reality warping powers works by changing the various variables of the objects of the world. As those variables and/or flags are changes, the affects on the world change. Ideally, this can only work on individual objects but occasionally there's a person that has higher rights and might be able to affect a superclass or a group of objects. Depending on the strength of the reality warper, they will have specific access to affect changes in the programming values of the various objects of the universe. Of course, like any good systems, there are forces that are there to prevent malicious or undesirable changes to the code. The sysadmins of this reality program should be checking into malicious changes, but they are busy with their sister and her boyfriend. ## The Laws of Reality As stated, there needs to be some laws to keep reality working properly. To keep the programming metaphor going, you can't change reality in such a way to create a syntax error in reality and crash everything. As such, there are four rules that this reality changing power adheres to in order to not break anything with a description to follow. 1. **Law of Paradox Prevention** -- No statement can change reality in such a way as to create a paradox 2. **Law of Awareness** -- For a statement to change your reality, you both have to perceive the statement and have it make sense 3. **Law of Subjective Reality** -- What you perceive is not what somebody else may perceive 4. **Law of Collective Reality** -- The belief of the multitudes is stronger than the belief of one ### Law of Paradox Prevention This rule prevents things that would cause a paradox in reality trying to resolve it. As a rule, it's pretty straight forward -- you can't kill somebody yesterday by stating it today. From a programming perspective, it's about using data validation to ensure that your programmed changes in reality don't cause an error in the system and crash it. Whether the validation is on the data of reality as a whole or on a person, the point is that what you say is vetted to not crash the system. Error checking is very important when it runs reality. ### Law of Awareness If a tree falls in the forest and nobody hears it, does it make a sound? That, but applied to reality warping. Basically for reality to change, somebody has to perceive it. In the context of the question: Joe can say that the sky is black, but if nobody hears it, then really only Joe is affected by the statement. Should other people hear him, they will believe the sky is black Going back to the programming metaphor, you have to not only have access to a Person object to change their reality, you have to know about that Person object in order to affect it. After all, you can't change code that you don't know where it is. The same would be true no matter what entity you're referring to -- the floor, a rock, a tree, etc. ### Law of Subjective Reality As it says -- Reality is subjective. What I see may not be the same as what somebody else would see. For a more literal example, compare the vision of a colour blind person compared to an average person (trichromatic) or a tetrachromatic person. Alternatively, using the 1 + 1 = 3 example, there are multiple ways to resolve this statement. One could always see an third item where there are supposed to be two as per the question. Alternatively, one could resolve that statement by the reversal of 2 and 3. There are absolutely a host of side effects with that interpretation, but there was nothing in the assertion that denies that perception of the new reality Programming-wise using the sky is black statement, the Person object could have a colourIsSky variable. It could be black for Joe and those he has told, but for the rest of the world, it is blue. The variable values are different for different Person objects. ### Law of Collective Reality In short, many people believing something will make it harder to change by an individual. Consider the idea that Joe says that the sky is black. By telling me, one could argue that I will now perceive that the sky is black. But I believe that the sky is blue, as does common knowledge believe that the sky is blue. Using the programming metaphor, there's two things in action here. The first is that multiple people are trying to change the same variable in the same object. One way around it is to consistently change the value, but it is taking the other way and locking the value in until the conflict in the changes is resolved. For things believed by the masses, the variable that was once editable is not a constant value and unable to be changed by the average person -- one needs higher permissions to change a constant value. [Answer] **The Matrix resets** When an invalid operation happens the system crashes and resets itself, loading the last autosave from a valid state. [Answer] It happens all the time already, it's called propaganda... Just an example: "Hitler was far right" was repeated so often that billions of people believe it like gospel, despite Hitler himself ALWAYS having said he was a socialist and that fact being well published. Tens of millions (maybe hundreds of millions) of people believe that Covid-19 vaccines are bioweapons, that the disease doesn't exist, despite all the evidence to the contrary, simply because they choose to very selectively believe certain people over others, disregard any information that doesn't reinforce those beliefs. The hard part (and it's not that hard, a lot of (maybe even most) people are extremely gullible) is planting those first seeds of misinformation in a believable fashion. After that the hoax takes on a life of its own and once it gains critical mass there's almost no stopping it. That's what charismatic people are so good in, making people believe the weirdest things and disregarding reality. [Answer] ## Sentences are interpreted by the worst, but kindest Djinn You know how evil genies of the lamp alter people's wishes? That, for instance if you wish to be incredibly powerful, they transform you into a powerful yet crazy monster? That if you wish to be the richest in the world, everyone's purse get empty excepted yours which now contains a single gold coin? Your idea is following the exact same principle, excepted the djinn listening to you is the guardian of this world : All texts are wishes, and all are fulfilled in a way that ends in the least damage possible to the current's reality. This is getting into story territory as wishes's contents are driven by the story, not by the world. However, I'll give answers to some examples you raised out, so you get the gist of how to interpret them : * (You wish) the world is engulfed in an universe-wide inferno : Of course... In 50 billion years, when a new big bang will happen. The time is given? Well, too bad you didn't say which kind of world it was. Perhaps the little Earth-globe on your desk just turned into cinders. Or perhaps it's *your* world which got burned to ground, so your family and your village went into blaze? * "Kazeiormlqsdkl" : Was that ever a wish? If we make an analogy to computer science, this sentence will raise an error at the execution, and so will not be executed. * (You wish) Life never came to existence. Great, everyone are technically (un)dead now, since this world became some kind of temporary heaven/hell/purgatory. People don't know it, of course, since the sentence was not about remembering their previous life. Or perhaps it's just that life was always here now? * (You wish) You make reality exactly as you think them. Congratulations, you vanished into the air and are now part of the universe. You will make reality as people (they now are part of you) try to change reality. Since you're now the Djinn, you'll think about each wish like the original Djinn, ie. interpret them in its kindest way. **Understand that as long as you're not showing good will, there will *always* be a way to turn a sentence "the wrong way".** An omnipotent deity will always find something, even if wishes are made one after the other. ## Note on your world As I read it, your world will be hard to sustain, both from an in-world perspective and for your audience. Let's say that there are thousands of people, with even a meager 10% potentially writing wishes every day. This is still a lot of reality-changing wishes, a lot more than what is possible to understand as one of its reader. To reduce the risks of breaking the suspension of disbelief and losing attention, you'll probably need to give strong conditions to call upon wishes. There's a reason in fairy tales djinns only grant 3 wishes/person, and that there's at most one or two djinns in the world : It keeps the topic raised by such powers focused on what you want to tell. Adding rules like "You cannot wish to have 100 more wishes" also prevents altering the system against your favor. In this case, I believe you want people to keep altering reality, so you might want to add an innate rule that you cannot write that "texts can't change reality". To end this part, **remember well that wishes are a very convenient and powerful tool for the story, not for the world it is happening in.** [Answer] **the world this happens in is fictional** this idea would be incoherent if applied to a real world with actual natural laws that have to be consistent. but luckily, this is worldbuilding for the purposes of fiction (unless you happen to be god ofc). the world it's happening in actually is made of words (or pictures if you're making this in some visual medium, or other symbolic sense-impressions). it can contradict itself and contain lacunae freely. if facts made true by speaking them override merely empirically observed facts, then contradictions are only bad when they're between such facts-by-fiat. if the sky is black now, the physical implications of that need not be relevant since the reason the sky was blue yesterday wasn't because of physics, it was because that was how you described it. if someone does say "p and not-p", then any consequence may ensue, but that doesn't mean every consequence must ensue. since a story is generally a linear sequence of events, you can just pick one possible consequence that you like. i usually go for 'something explodes' when i write about this sort of thing, because it's the [principle of explosion](https://en.wikipedia.org/wiki/Principle_of_explosion). which is to say, if a character does choose to locate and observe a lacuna, presumably they'll be eaten by a [wogly](http://hitherby-dragons.wikidot.com/the-rent-in-the-fullness-of-the-world-i-ii). [Answer] You can achieve this effect *right now* using **magic** - the real kind, defined as "the art of changing consciousness in accordance with will". It is already being used often, and with great effect too, by many people who are very much like your Joe. Advertising for example practically runs on magical formulas; so does seduction, and political slogans. Making people believe that 1 + 1 = 3 would require *some* more sophistication, but is perfectly doable in this way - and since we generally believe that magic cannot possibly work, we lack ways of protecting ourselves from bad faith actors. ]
[Question] [ JE is a famous man that has an extensive amount of information incriminating the powerful of this world. He would like to ensure that an "unfortunate accident" does not happen to him by clever use of this compromising information. He is therefore looking for a solid dead man switch that would have at least have the following characteristics: * release of the documents (can be digitalized) when not acknowledged for some time, or when the acknowledgement is not correct * inability to modify the documents once they are in the vault * resistance to electronic warfare (decryption) These requirements are simple to satisfy technologically; * resistance to torture: JE could be tortured + to reveal the people who hold the information, so there must not be reliance on the typical "*Marc: if I do not talk to you once every 3 days, send these papers to the press and the justice*" + to disable the dead man switch * resistance to a nation-backed effort to block the documents. This would be a secret operation (say, the President would like to quietly use some of the country shady forces to do [something] - but not a nuclear strike), so the protection must stay in the realms of realism These requirements are the ones I do not exactly know how to satisfy. Other reasonable requirements are welcome. Everything happens contemporary, in our world with our technology and political context [Answer] There are a few pretty good hardware suggestions already posted to trigger a switch, I would like to expand on how you can make this message incredibly tough to scrub from the internet for the torturers of your protagonist. The following only really works assuming that the internet is running as it does now with decentralized networks readily accessible and maintained. Real projects exploring the idea are: <https://killcord.io/> and <https://sarcophagus.io/> - they work on the similar principles - 10,000s of copies of the encrypted message are owned by nodes either on the Ethereum network or IPFS network which are maintained regardless of their content. Upon "death", that is, failure to enter in a liveness password to a smart contract usually on Ethereum after some fixed time period, a key is released to the blockchain that allows anyone to decrypt the encrypted message alongside emails to any relevant parties to look at the entries - the dead man's switch can be disabled or triggered directly using appropriate commands to this smart contract. I would also expand a little on how to handle the "under duress" scenario for your crypto-savvy protagonist, it's possible to modify the above ideas to use either: 1. Deniable Encryption: which is a method to provide keys which decode the encrypted message to something related but not exactly the original information your character is attempting to smuggle. 2. Steganography: decrypting your data to files which appear compromising but actually contain the truly compromising information within them as carefully chosen flipped bits. Both of these could fool a would-be torturer into thinking they got the information but actually end up disseminating them to the public in a slightly more hidden fashion. [Answer] Custom electronic devices, at least a dozen of them. They use pre-paid SIMs, are plugged into the grid somewhere. At least a dozen of them, scattered across the country (or several countries). These devices are programmed to contact each other periodically, which is at least every 3 minutes. Each device contains a copy of the documents, and if it sees any other device drop out, it emails the documents to major news outlets, tweets them, everything. Thus, to disable these, one would have to find all of them and disable them simultaneously. If you got 11 of the 12, the 12th just finishes the job. You thought there were 12? Oops, actually 13. And he checks in by hitting some Onion (Tor) url. If he misses a checkin, they send the documents. He could even have a second address, which if that one is pinged the documents release immediately along with a "I'm being tortured" note. This doesn't rely on other people (except to design/test the devices initially). He can be under surveillance before arrest/detainment/abduction. There's no secret information he has which can be cheated out of him or guessed... he may set it up so that he doesn't even know the location of the devices, the number, or any of the technical details. It may be designed so it can never be disarmed (just that new documents can be added to it). And of course, the devices can scan headlines looking for "Joffrey Epplestchien dead" keywords and trigger on that as well. Of course, likely needs to hire a hitman to deal with the people who implement the system. Just like the guy who designs the castle secret passageways, those people aren't going to come to a good end. [Answer] ### Get a postal / hotel / etc worker to inadvertently send the documents to the media for you. I don't know about the rest of the world, but in Australia you can address mail to "C/O <a specific post office>", they will hold it for you and you can go and collect it with ID. If you don't collect it within 6 weeks, they return it to sender. Many hotels will also hold mail for a limited period for guests who haven't arrived yet. Who hold what for how long is probably best determined by experimentation in advance, (just send some test letters and see what happens to them). 1. Put your incriminating evidence on a microSD or some other small, dense media. 2. Put the microSD card in an envelope packed with some blank A4 pages. 3. Address it to either an alias that you have a fake ID for, or a slight misspelling of your name, care of a post office or hotel. "Jefary Eipstiin, C/O Gold Coast Resort Post Office, QLD, Australia." 4. Write the return address as your chosen reporter. "Sender: Bob Woodward. 1 watergate road." 5. If all goes well. Rock up at the post office and ask for any mail for you. Collect it, put it in a new envelope addressed to another post office with a new stamp, and mail it immediately. 6. If the government attacks you, arrests you, or you die, ~6 weeks later the post office will return the mail to "sender", delivering them to the reporter for you. 7. If there is mass surveillance, by having the mail in an alias or mispelling of your name, its unlikely to be found by an investigation doing a massive government database search, at least not before the 6 weeks timer runs out. Also worth keeping another copy in a safe place - safe deposit box in a bank kinda thing - if you're captured and tortured it'd be handy to give your torturers something so they stop torturing you. [Answer] 1. Create a digital archive (e.g. a zip file) with the documents. Create a private/public key pair, sign the file, destroy the private key and publish the public key. Now anyone can validate the integrity of the archive and nobody, not even you, can make a new version. (This step has a slight weakness regarding the nation-state criterion. A breakthrough in quantum computing or a giant server farm could make additional, altered versions of the archive to muddle the waters.) 2. Describe an encryption scheme which relies on several one-time-keys. That can be as simple as a bitwise addition. Create more keys than you need. Encrypt the original with different variations of keys, creating multiple ciphertexts. Now anyone with one ciphertext and the right keys for that text can decrypt your archive. If the result is a signed zip, obviously the elements matched. If not, try again with another combo. 3. Spread the ciphertexts and keys to lawyers in different countries who are paid to release them if certain conditions are fulfilled. You are betting that enough ciphertexts and keys will be released so that a matching set is among them. How many you need depends on your need for certainty. (This can be made weak, with risk of non-release, or strong, with risk of premature release. Remember that anything you know is presumed to be spilled, so it cannot simply be "I posted a selfie on Facebook." Make it a condition that shows freedom of action: "I visited my villas in 5 out of 10 locations last year and got pictured by paparazzi." The character might know that he has to arrange being photographed, but if he can travel that wide he is free.) 4. Pay several terminally ill lawyers or bankers to arrange the data-holders from step 3 for you. People whose medical prognosis looks bad. Make sure that none of them has a *complete* set of ciphertext-and-keys, to limit the damage if they have a recovery and then get pressured. Once the expected happens (no need for foul play if enough ill intermediaries were involved) you cannot recall the messages. Bonus feature: powerful people will know what happens when you are sued and have to sell your villas abroad, or if you even have to turn your passport in. [Answer] ## Ignorance Is Bliss: This kind of deadman news release can have two functions, and the answer will be slightly different if it's only about releasing the data. So I'll assume the primary motivation is to make JE immune to attacks or imprisonment by the threatened governments and/or organizations. To make this work, you must set up conditions such that no matter what the governments do, they always believe the information will be released if JE dies under any circumstances OR is imprisoned any more than momentarily. The best way to guarantee you can't influence or control the release of the data is to no longer control its release yourself. You need some shadowy figures involved that JE is not directly aware of. Then these people are in charge of monitoring JE and assuring that the predetermined set of conditions are met. If JE is a public figure, he must agree to a set of conditions: * **Let your enemies know about your plans**: Obvious, but everyone who is being blackmailed must know. If, however, you let enemies of the government know, you're painting a bullseye on your back for anyone who WANTS the release of the info. * **Be sure the information being released isn't known to your agents, and can't be understood until it is released**: This could probably be achieved with some kind of coding or blind information-mating. If your agents (who, after all, you DON'T know) are able to view the information, they may use it themselves to blackmail the government, making it's use to JE greatly diminished. * **Remain a public figure**: If JE is free, then the shadow agents don't release the data. This could mean JE must show up at a certain public place on a regular basis, tying him to a place. Or, imagining JE to be so high profile that they make the news, the data is released if JE disappears for a predetermined amount of time or dies. * **JE agrees to the release of protected health information to an undisclosed place**: If JE gets sick, he must go through a certain health network. His doctors agree to release a copy of his health records to an anonymous file destination (form TBD) so if he has a short-term health emergency, the data isn't released. * **Entrust the arrangements to a terminally ill employee**: You need someone who is totally loyal to JE, but is dying. They take the money to pay the shadow agents, find them, set up the preconditions, and then die. The secret of who has the files is gone. Even if the terminally ill employee lied and didn't set up anything, JE will firmly believe the loyal employee did. Under torture or drugs, it will be determined that keeping JE prisoner or killing him is counterproductive. In fact, it might even be MORE effective if the dead employee never set up shadow agents - after all, you can never disprove a conspiracy that you believe to be true, but isn't. There would always be the doubt that they were out there waiting to release the data. I would couple this with a more conventional deadman-release method just in case there was a failure in the process, or the shadow agents fail to perform. But JE's enemies couldn't do anything to JE to get the info, since JE doesn't have it. [Answer] **sensors coupled with low frequency emitters inside the body** **Signals** First off, you need to determine if the person is still alive. Easiest to do this is by having a sensor that measures heart rate. No pulse and the information is sent. Embed the sensors in the body, possibly multiple, to make them hard to reach. Second, you need to be able to send a signal to your vault when the person is diseased. Low frequency signals are difficult to block. They are sometimes referred to as 'slow', but in truth it's the information density that is at stake. You simply cannot cram a lot of information over time. This isn't a problem, as your message can be short. Just an 'ok' or a 'release' message, however coded, is enough. Release always has priority. If multiple signals are detected it'll release (expect only one!) And if it's garbled it will release after a time if it doesn't get the ok signal in time. It is important to get a different signal within a longer period of time, like a physical button or via protected internet or something, to make sure the signal hasn't been replaced. That thus means one standard method, with some factor authentication if required. Sensors can also find increased stress levels from injury or threats. If this is prolonged, like in a torture situation, the signal is sent. Same for not expected anesthetics and the like. This to prevent them accessing the sensors in the body without stress response. If sensors are disconnected, they should also give off the signal. Finally the switch can be triggered by the person himself in multiple ways. Like saying some words or the like. That way, even if the person isn't in direct danger but held captive, he can still trigger his weapon. The sensors and the like should use as little magnetic materials as possible to prevent EMP attacks. **Documents** To secure the documents you can use signing. If you've ever encrypted documents with, for example, PGP, you know that tampering becomes quite difficult. Not just because you can encrypt them, but sign them. The document itself is used for this, so if the document is changed, the signature will show this discrepancy. With a ton of huge servers around the world, the documents can be encrypted at multiple owned locations as well as hidden on existing servers. Include some air gapped systems that dump everything on the internet or other media that is available and can update only periodically (or not at all. You have enough dirt already!), you can protect yourself from nearly any full scale attack. **Additional methods** The use of this deadman switch is multifold. Regardless who attacks this person, everyone is at stake. That means many people and/or nations will actually facilitate many things to prevent the death, torture or other release scenario's. That also means many state defences can assist the person in protecting him and the data. That way the person can even have the encrypted documents at a nuclear silo facility or the like, or even request his own secret sattelites to receive the signal and release documents when needed. Make him comfortable and safe. [Answer] **To resist torture** 1. The deadman switch is an opt-out mechanism with a short recycle timer. Torture takes *time*. Torture becomes more endurable if the amount of it you have to withstand is a known value. If the victim is being tortured, and knows there's only a few hours left on the deadman, he is very likely to be able to do some combination of stalling/enduring to reach a point of no return at which point he is free to fully co-operate with his captors. Depending on the state of due process in the likely scenarios, anything from 24 hours to two weeks is a reasonable recycle rate. 2. Have a panic button. Some way to give a false instruction, or a seemingly analogous process that, instead of resetting the switch, triggers the deadman action. In the event he is even *threatened* with torture or death unless he complies, he can announce that he has a deadman switch, even describe it's nature. Now his captors have to make a choice: believe him, and convince him to disarm it (at which point he can hit the panic button instead), or disbelieve him and the torture is now irrelevant to the deadman, because they're not after information about the deadman. **Resistance to gov't interference with mechanism** 1. Self-publish. Generally speaking the only way a gov't can control a release of information is through censorship. Once data is outside their control, it's too damned late. Shotgunning the information to as broad a mailing list as possible is sufficient - by the time the gov't sends an instruction to whatever systems to stop the flow of information it's too late: those instructions are traveling at the same speed as the data itself, it will always remain ahead of them. [Answer] ## The Documents are in Plain Sight You’ve already deployed the cache. It’s on Pirate Bay and other torrent sites, already residing on hundreds or thousands of hard drives. Copies are on web sites you or your friends own, just slightly off the beaten path at “main.html” instead of “index.html” and hidden from bots and scanners. What you are relying on is that when you disappear, it’s going to get some people interested in you. When people start putting effort into reviewing your files and writings, they will find one (or several) of your caches. ]
[Question] [ In my setting, rail guns, point defence lasers and supersonic missiles are the weapons of choice. What I'm wondering is, **how do these weapons change modern naval warfare.** More specifically, ship design, engagement ranges, and general tactics and doctrine. For the sake of simplicity, let's assume the technological challenges have been solved. Edit: The missiles would be the surface to suborbit to surface variety. And only because they have a large carbon nose cone to survive reentry and laser fire. Anything else is blasted by the laser. They are also expensive compared to the rail gun and laser. And that's not accounting kinetic defence systems. [Answer] In a state of warfare like this, ships would be incredibly obsolete. The technologies you mentioned would—as Willik stated—be catastophic to the entire endeavor of naval warfare in their own right, but I think that the *implications* of those technologies quite easily allow for anti-naval strategies even more devastating. Take, for example, the extensive use of suborbital ballistic missiles—for all intents and purposes, ICBMs. If the technology and resources existed to mass produce such missiles on a scale where they could become a dominating force in naval warfare, the same advanced rocketry could be used to launch kinetic orbital strike platforms. I think that a 200 tonne tungsten rod dropping out of the sky at massive velocity and shattering the largest capital ship on the waters would quickly put an end to naval warfare. If accuracy would prove to be a limiting factor, there are still options available. The most devastating that comes to mind would be the use of tungsten rods with a dopant of relatively lower melting point and/or relatively higher thermal expansion irregularly incorporated during the sintering process, such that they would shatter into thousands of pieces in the low stratosphere. A close call with a fragmentary payload would have the same net result as a perfect bullseye with a solid one, except it wouldn't just sink the capital ship, it'd rip to shreds the entire fleet and any particularly unfortunate aircraft that happened to be accompanying. If orbital lazy dog cluster munitions seem a bit too, uh, warcrime-y for the scenario you're envisioning, I have another notion for dealing with any accuracy issues, by letting the enemy calibrate the drop *for you.* By launching multiple long range, small scale (although perhaps appearing to be large scale with the use of advanced corner reflectors, IR emitters, etc.) missile strikes on a valuable primary target, they would be spurred to block with point defense systems, lasers, and the whole shebang. This gives you about 30 minutes of radar, lasers, and chatter lighting up the electromagnetic spectrum with all the data you need to determine the position, heading, and speed of the target to infentissemal accuracy—enough to split an aircraf carrier straight in half from orbit, even if the initial rocket attack was a ploy with cheap dummy loads. Any of these orbital strike tactics would no doubt be very costly, but they are absolutely feasible within the framework you've provided, and they have the special characteristic that they would change the entire nature of warfare even if you only used them **once.** Or, *not at all.* Then, there's railguns. Hmm. I have to assume that a ship equipped with such is carrying a tremendously powerful nuclear reactor on board, as there's not really any other feasible way to provide the necessary energy. This seems like a potential misallocation of resources. Once railguns are refined to a level near what would be necessary for ship to ship engagement, their range will only be restricted by the energy available. Why not then instead place the railguns on land and provide them a far larger power supply capable of striking ships from land? This gets uncomfortable very fast. Imagine coastal artillery in Maryland capable of continuously shelling the Straits of Gibraltar. Boats aren't looking that great. As a last afterthought, it would be potentially devastating to exploit an opponent's laser weapons systems against them. One method that comes to mind is the clever use of electromagnetic absorbance peaks. If I were in a situation, let's say, where I've been launching missiles at an enemy vessel only to have them shot down by lasers, and I measured the frequency of the beams to be around 2.5 MHz, I'd be thrilled to ditch the expensive warheads, guidance systems, and adjustment thrusters, and cheerily launch a tremendous salvo of unguided dummy rockets carrying nothing but giant wads of plasticized propylene glycol. As soon as being hit by electromagnetic energy in that bandwidth, the glycol would superheat and expand extremely abruptly, turning into gigantic clouds of flaming, viscous aerosol on the exact same trajectory and with the same, if not greater, velocity. There are other chemical compounds that would produce devastating results as well, and in response to other wavelengths, I just have some particularly shocking memories as to the behavior of that particular chemical when exposed to microwave radiation, and the scars to prove it. [Answer] **Nothing on the surface.** In this scenario, topside ships of any size are sitting ducks. If your oceangoing vessels are going to survive they need to all be subsurface where a thick blanket of water protects against lasers, railguns and missiles. [Answer] Perhaps there would be an increased emphasis on stealth and other methods of cloaking or generating disinformation as to the whereabouts of a warship. Because a supersonic missile is useless if the enemy ship can't be detected or tracked. Electronic warfare would be particularly important. If an enemy can be detected before they can detect you then the enemy would probably be doomed. The timing of engagements would also be very short lived and highly automated. Enemy ships could be detected, multiple missiles fired, counter measures switched to maximum, decoys activated and the enemy ship destroyed utterly in less than a second. [Answer] In some ways, naval combat would go back to how it was pre-WW2. If you have lasers capable of reliably intercepting hypersonic anti-ship cruise missiles (such as the upcoming [BrahMos-II](https://en.wikipedia.org/wiki/BrahMos-II)) then aircraft that have to carry meatbags have no hope. No aircraft carriers, though ships might reasonably expect to carry drones for reconnaisance use. The maximum range of a railgun round is going to be a few hundred miles, max, and you'll need a good firing solution on the target to hit it at that range. That's a far cry from autonomous hypersonic fire-and-forget antiship cruise missiles or long range strike aircraft, so ships at sea will be much safer than they are now. Lasers and railguns need power, and lots of it. Bigger ships mean beefier weapons. The ineffectiveness of antiship missiles mean that smaller ships no longer have effective long-range means of assaulting larger ships, so if you want to take out a battleship, you'll be needing your own battleship. Big railguns can hit targets over the horizon, but you'll need to be able to spot your targets first. Hopefully your recon drones will be able to do that without getting shot down themselves. Even high altitude reconnaisance aircraft are vulnerable if you can strike targets in orbit, so there's a bit of a visibility gap... satellites could help, but you don't want to risk filling orbital space with debris if the first phase of any conflict is to shoot down everyone's recon satellites. Possibly there will be large constellations of [small recon satellites](https://en.wikipedia.org/wiki/Small_satellite) that are resilient to damage (because they're tiny and hopefully cheap and you'd need to take em all out to blind your opponent). Possibly ASAT missiles will be backed up by sensor-blinding lasers for soft kills. Increased stealthing will make it harder for ships to be stopped from afar, luring reconnaisance drones in closer where they can be more easily spotted and dispatched by point defense. I suspect the next-gen US navy ships like the Zumwalt class might be a taste of things to come: [![USS Zumwalt](https://i.stack.imgur.com/X7dND.jpg)](https://i.stack.imgur.com/X7dND.jpg) The [Lyndon B. Johnson](https://en.wikipedia.org/wiki/USS_Lyndon_B._Johnson) has been built such that its conventional(ish) cannon may be swapped out for a railgun. I guess the tricky bit will be working out how things work for submarines. Modern antisubmarine tactics often involve some kind of air support, and that's still practical when you're defending yourself because there probably isn't any enemy point defense immediately available. I honestly have no idea how modern antisubmarine tactics work, or how effective modern attack submarines may be... there aren't many actual combats involving them. I'll just halfheartedly wave my hands and say things in that regard probably won't change a whole lot (and given their short range [supercavitating torpedoes](https://en.wikipedia.org/wiki/VA-111_Shkval) are unlikely to decisively tip the balance). [Answer] The USS Virginia and the Indian Navy's Arihant-class submarines provide a hint of what the future might hold. While notionally attack submarines (SSN), they actually have the ability to carry and fire strategic weapons. The Virginia displaces 7000 tons, while the Arihant displaces about 6000 tons. [![enter image description here](https://i.stack.imgur.com/RZvFX.jpg)](https://i.stack.imgur.com/RZvFX.jpg) *Arihant-class submarine* Couple this to the ability of the submarine vessels to network to sensors carried by unmanned vessels, UAV's overhead and satellite vehicles like the X-37, and the name of the game in naval warfare becomes a very deadly game of hide and seek. The submarine has the persistence to remain on station for a period of weeks or months, meaning there is an unseen threat out there, capable of striking targets at sea or along the coast in a matter of minutes if it is carrying hypersonic missiles. [![enter image description here](https://i.stack.imgur.com/UWUN8.jpg)](https://i.stack.imgur.com/UWUN8.jpg) *Unmanned surface platform for sensing and communicating with the submarines* The counter will be an equally extensive network of sensors, connected to high speed platforms carrying anti submarine weapons. These could be unmanned ships, aircraft or even lighter than airships-essentially weaponized blimps which provide the persistent overhead coverage over areas while high speed platforms dash out to prosecute contacts. Submarine captains will need to be very alert to prevent revealing themselves to these sensors, since an aircraft dropping a torpedo or a cheap unmanned ship firing a rocket carrying a torpedo to the target box will not be detected until too late. [![enter image description here](https://i.stack.imgur.com/rPa4r.jpg)](https://i.stack.imgur.com/rPa4r.jpg) *Unmanned torpedo boats heading to a contact* Since the OP has also stipulated railguns and lasers, the hypersonic attack missiles will have a challenging gauntlet to pass through to reach their target. The best way to deal with this would be to overwhelm the defense with more missiles, but this could be problematic with a compact SSN based platform. Remote "arsenal subs" could be part of the mix as well, designed to trail the SSN and possibly receive commands via fibre optic cable to the controlling sub. So tactics would revolve around creating vast sensor networks which submarines would link into (on their side) and attempt to avoid on the enemy side. They would have unobtrusive means to communicate with their sensor networks (possibly floating laser transmitters and receivers connected via fibre optic cable). The defender would be prosecuting contacts with a variety of persistent and high speed platforms to keep the submarine off balance and less able to carry out the mission. [Answer] **Unstoppable attacks. Indestructible defenses. *Yeah. Right.*** Ever since people were replacing the stone axe with copper, they have been enthusiastic about new weapons that would either be so effective to make war a cakewalk, or so terrible that war would be utterly impossible. Neither one has happened. Thirty years ago, there were professional naval writers who proclaimed that navies would consist entirely of stealth missile boats, since anything bigger would be a sitting duck. A bit over a century ago, writers argued over the merits of battleships vs. torpedo boat destroyers. And so on. **Expect gradual change.** You wrote that technical problems have been solved, but they are never *completely* solved. Point defenses depend on **sensors** to detect the attack, **computers** to direct the countermeasures, and the **weapons** themselves. Either one could be overcome. Both sensors and weapons have limited fields of vision respective fire. Lasers will have "deeper magazines" than point defense missiles or guns, but they could still be limited by factors like overheating. The computers may be overcome by more (and more stealthy) targets than they were built for. Railguns need a power supply (just like the lasers) and will have issues of rail corrosion and heat management from sustained use. Just like the barrels of conventional guns. * **Improved point defenses** mean that attacks must be more separate missiles to saturate defenses, better coordination for time-on-target attacks, and better stealth to look like a random wave crest. * **Railguns** will be one way to put many cheap attacks on target and to keep the lasers busy. But ballistics limit the number of shells that can arrive time-on-target. (Within limits, that can be done. See modern field howitzers.) * As gunnery ranges go up, **targeting** with on-board drones or helicopters and off-board data sources like AWACS or sats becomes more important. Problably unmanned drones rather than manned helicopters, if the point defenses can reach out to the horizon. We reached the point where battleships can fire beyond the visual horizon a century ago, an early cause for the development of naval aviation. * If things get more hostile over the surface, there might be more emphasis on **submarine** attacks. Do you know *ASROC*? Well, imagine a cruise missile which delivers a big, wake-homing torpedo like the Soviet DST92. (Expect amateurs waxing eloquently about them being the ultimate anti-ship weapon. They're not, either.) * For that matter, long-range UUV go prowling after enemy targets. * Powers with relatively weak navies might have shore batteries with **ASBM**, anti-ship ballistic missiles. But where do they get targeting data? Perhaps **over the horizon radar**. Or **hackers** reading the enemy mail. [Answer] None of the technology you mention is really new, but I'm assuming your hypersonic missiles, railguns and lasers are a significant advance compared with today's technology. Logistics and support will be the key, as ever. How reliable are the various systems, how expensive are they to operate, what's the availability of spares and consumables like? Can you afford the cost and space to fit all of them to every ship or are they such high cost that only capital ships get to have them? Which has the advantage, the hypersonic missile or the anti-missile defence system (and the sensors it employs to achieve lock on the incoming threat)? Can you afford to blat away at a target with your railgun and hope that a round or two gets through the lasers or are the rounds 10 million dollars a pop? In this game of rock, scissors, paper^W^W^W missile, railgun, laser if the missile / railgun beats the laser then expect to see increasing investment in stealth and detection capabilities, as the first unit to detect and fire on its target has a very large advantage. Additional research into mitigation technologies such as chaff, flares, decoys might improve survivability against active homing missiles and rounds. If on the other hand the laser defence system consistently beats the missiles and railgun rounds then the ideal system to kill a ship becomes a submarine (or ship-launched torpedo, but torpedoes have limited range so it's nice to be able to get into range undetected by using a submarine), so you would expect ships to focus more on anti-submarine warfare and protection against the back of the ship being broken by the way a torpedo works. None of this will make much difference in unbalanced wars: if you have a superpower going up against a small nation with last-generation weapon systems, the superpower will win. The same happens if one side can massively outbuild the other, spending more to build more ships or build them quicker. In wars where the two sides are roughly equal parity, each side will be desperately spying on the other and analysing early clashes to try to identify weaknesses in the other's technology and tactics and exploit them: it will then be the side with the better intelligence that wins. [Answer] # Observations ### Strength in numbers If both your long range weapons and point defenses are reasonably effective (i.e. neither is made obsolete by the other), a single ship, no matter the size, will quickly succumb to a coordinated strike from multiple directions. Depending on your radar, electronic warfare and drone technologies, determining its exact location might not be easy, but your missiles *don't need* an exact location. However, in a well coordinated strike group, each ship's point defenses should cover the entire group. The larger the group, the more firepower and coordination is required to score *any* hit. In the same vein, you need more and more accurate targeting data to distribute your attacks in a cost effective manner. Economically, sustained missile fire will bleed you dry much more quickly than keeping your lasers running for a while longer, so the attacker is under quite a bit of pressure to hit high value targets. ### Accuracy will limit your railguns While the range and volume of fire that a battery of railguns could offer would be impressive, firing them "blind" will not do you much good against a sufficiently distant and mobile target, especially one that has railguns (and perhaps short range missiles) of its own that can also be used defensively. You need eyes on the enemy, and those eyes will be susceptible to counterattack. ### Cold war in orbit The cost of putting significant mass into orbit, widespread availability of "satellite-killer" missiles and the very real danger of [Kessler Syndrome](https://en.wikipedia.org/wiki/Kessler_syndrome) suggest that attack satellites and the like would be used very sparingly, if at all. A network of small, hard to detect satellites that provides targeting data and detects incoming missiles appears much more useful. Warfare in orbit would revolve around locating and blinding enemy assets and disrupting their communications rather than hard-kill measures. # Conclusion: How a naval battle might look A satellite or patrolling UAV detects the enemy fleet far beyond visual range, transmits coordinates and half a minute of video before going silent. Almost immediately, a swarm of UAVs and missiles is launched towards the enemy, followed by the (mostly unmanned) escort vessels. Somewhere between the two fleets, the drones engage in a short but intense air battle while the escorts establish a defensive perimeter. **The fleet is now roughly split into three groups** Carriers, missile cruisers, destroyers (and/or large submarines) keep their distance from the enemy. They're the fleet's long range firepower as well as the juiciest targets. Using targeting data from the other groups, they take out enemy escorts and point defenses until it's time to strike a decisive blow. Escorts spread out towards the enemy. Their first job is to intercept as much of the initial missile salvo (that's mostly targeting the bigger vessels) as possible. Once in position, they deploy small (surface and subsurface) recon and attack craft. The more area they can cover, the harder it will be for enemy assets to get eyes on the rest of the fleet before they're met with overwhelming point defense fire. Drones and smaller submarines mostly provide targeting data on the enemy escort vessels and take out forward sensor assets. If they can bypass the perimeter (or a satellite picks up the enemy fleet), they help track priority targets. Eventually, one side loses too many escorts or makes a tactical blunder, which leaves them open to a decisive railgun and missle salvo. Once they lose their long range firepower, the battle is over. [Answer] To set the stage for discussion, in olde times, naval battles were fought in engagement ranges proportional to the gun ranges. As gun ranges increased the circle of engagement grew larger. Then, the use of aircraft and missiles increased the circle of engagement to their largest dimensions since fleets could strike one another at distances of more than a thousand miles -- for the sake of argument. I think your addition of effective laser defenses takes aircraft and missiles off the table for most parts shrinking the engagement circle again to gun range. Your addition of rail guns pushes the engagement range to the horizon again, and in a limited degree over the horizon. I'll assume that getting hit by a direct round from a rail gun would destroy or cripple another ship, that passive armor is ineffective for obvious reasons. Since the parabolic trajectory of a ballistic round or guided round won't always intersect with the curvature of the earth these powerful weapons won't always have a firing solution for a vessel within range. And because traditional single keeled ships have to maintain a certain depth of keel to remain stable and assuming your rail guns have a limited range of vertical tilt, you'll end up with a sort of inverted donut of possible engagement circles. I think this means that double or triple keeled ships would enter the fleet. These could raise and lower with ballast without compromising stability and provide a smaller inverted donut and might do away with the problematic geometry altogether. That depends on the range of muzzle velocities and atmospheric breaking acting on a round. The defense against the rail gun rounds would become vitally important. I think it would be some form of active defense. small fast missiles carrying shaped charges. They wouldn't likely destroy a projectile, but they can detonate in their path and reduce their velocity. If the velocities can be slowed enough, the round will either fall short or not penetrate the armor. I think Russian tanks, among other countries, use a similar system to destroy inbound missiles or prematurely detonate rounds shot at them. I think this means that over the horizon (OTH) detection of rails guns would be really important to compute firing and maneuvering solutions to defeat focused firing attacks by multiple ships trying to swamp your defenses. Since the rounds would be faster than sound, underwater surveillance for detecting firing wouldn't be practical -- depends on the speed of sound underwater v. muzzle velocities -- so I'd think remote observation via drones or space or very stealthy ships would be necessary. But the lasers would make the difficult but not impossible with either numbers or very good stealth. Maybe submarine drones watching enemy fleets and communicating with laser beam to blimps flying over the fleet. [Answer] Naval warfare (except perhaps autonomous and submarine-focused) is largely obsolete in your scenario. Hypersonic missiles are plentiful - intuitively, this means people will build underwater torpedoes into hypersonic missiles, launch them at ships, and have the missiles drop the torpedo into the water before it becomes a target for laser defenses. Laser point defense might be even crappier than it looks on paper if people start putting mirror coatings on missiles to thwart it, in which case you might as well downgrade to a Phalanx. Another problem with laser point defense is that it provides very little kinetic force. Even if it's a sci-fi capital ship laser that will burn a hole in just about whatever you aim it at, it's vulnerable to attacks by swarms of impact missiles that travel in a ballistic path toward their intended recipient and contain an extremely dense 10-20 pound weight in place of a warhead. You can punch a hole in them and shut down their engines, but chances are that they're already on the correct path and that leaves dozens of 10-20 pound solid weights barreling towards your ship which will probably impact at Mach 2. Again, a Phalanx might be more effective at diminishing the incoming missile's velocity or causing it to break up completely. The railguns are a red herring. Forget them. This war that you mention is won with missiles, which will outrange just about any railgun due to air drag. tl;dr: * point defense lasers are highly overrated and in many practical respects outclassed by old-fashioned kinetic counterparts * railguns are deadweight and a waste of reactor space that should be used for missiles * hypersonic missiles are dangerous, nasty, and deadly. They quickly end battles - with brutal efficiency. * warships will go slowly extinct in favor of submarines, and their primary loadout will be a mix of torpedoes (against other subs) and hypersonic missiles (to pick off anyone who's dumb enough to keep using their warships) [Answer] The problem with sinking modern warships isn't a question of having weapons powerful enough to do the job, it is a question of having the right targets. What makes aircraft carriers useful is that their fighters and radar aircraft can appear from nowhere, while the carrier is moving such that it cannot be pinned down while still being able to recover its own aircraft. While it sounds odd, they actually are [capable of hiding strategically](http://www.navweaps.com/index_tech/tech-031.php). Stealth at sea is mostly about constantly moving and never turning on your own radar. You're going to need either large quantities of sensor drones or manned radar aircraft(which as a bonus can control drones, freeing the need for radio traffic from the warship) regardless of what weapons your warships have so that they can remain undetected until they begin firing. Obviously for your situation lasers are making this slightly more complicated, because they serve to make aircraft less survivable. But the detection problem also exists here. Your lasers can't hit what your radar can't see. Standoff weapons are already becoming the norm to survive against anti-aircraft missiles, which can even be fired over the horizon in the [most extreme cases](https://en.wikipedia.org/wiki/RIM-174_Standard_ERAM). Railguns and lasers aren't more effective than such missiles, they are simply cheaper to operate. Also, what do lasers do when it rains? Also ballistic missiles aren't guaranteed to get past anti-aircraft missiles either. This is what the [SM-3](https://en.wikipedia.org/wiki/RIM-161_Standard_Missile_3) was made for, and why just about every destroyer and cruiser in the US Navy is getting a couple. The fact that they can also provide anti-ballistic missile defense for other targets is a bonus(especially to Navy budgets). The biggest advantage to lasers is that they serve as an excellent counter to drones and other cheap assets like massed MLRS batteries(something Iran has plans to do), which are so much cheaper than defensive missiles they could wear down defenses from an economic standpoint. Railguns are mostly intended to be used for shore bombardment instead of relying on million dollar missiles or a risking a multibillion dollar destroyer so that it can shoot its short ranged deck gun every time a Marine wants fire support. They're not really intended to be used against enemy ships, which is reserved for missiles. As for submarines, the current trend seems to be that they would almost certainly dominate if there ever is a real war. The only reason why submarines aren't already ruling the seas is that there fortunately hasn't been a real war to let them prove this fact. Submarines are also not as useful at most of the things navies have actually wound up doing, like chasing pirates and waving the flag. It is also not for nothing that the US Navy has invested heavily in upgrading their helicopters and replacing their patrol aircraft to hunt submarines, as well as keeping up their numbers of subs. Oddly enough lasers are actually part of this picture, as a blue-green laser can actually help locate shallow submarines. ]
[Question] [ Beneath the sands of the Planet Dalia, their lives an abominable creature, a creature that eats beings whole and slowly, ***slowly*** digests them for years at a time. This creature is...The Tayan. Worshipped by the native aliens as ***dark gods***, most of the Tayan’s victims are slaves of nobles and priests, who sought to appease the dark gods with special “gifts”. As of late, Dalia is often visited by the occasional sadists, who want their enemies to die in the most horrific way possible. Most of the time, victims are stripped of most belongings, as to prevent any rowdy escape attempts. But, my hero steals a weapon, and falls into the Tayans fuller with it. The weapon is metallic, with a fusion power cell contained inside it. No acid can possibly corrode it, so god the Tayan it would mean an extremely upset stomach. I have just seen a huge design flaw in my creature. It’s maw is shaped in a way so that things can only go in, not out, so regurgitating indigestible materials that way is impossible. And it’s buried underground, so my question is: How can the Tayan regurgitate indigestible materials, given the circumstances above? ***Just Incase you want a visual representation of the Tayan, here is a photo*** ![enter image description here](https://i.stack.imgur.com/bxlCL.jpg) [Answer] # The Tayan is always growing upwards to match ground level Leaving any undigestable items behind. Say that in this environment the ground is slowly rising (sand, big rainstorms, dirt storms, dirt volcano, etc), so this plant creature has to always stay at surface level. Instead of moving upwards, it grows upwards to match. It will have a third compartment at the bottom that will compress extra material (metal bits, very hard to digest material, your gun) into as tightly as it can. It then uses a concrete-like or Amber sap-like substance to seal and solidify the unwanted material. New tissue has been prepared by the plant, and it grows a new bottom of the stomach. The old third compartment's nutrients are cut off by the plant, so it can save resources. This also gives the plant stability as it now was a solid pad to be on top of. This also provides other story opportunities, such as finding fossilized things under these plants or people hiding things in acid proof boxes to hide them and make them unobtainable for years until the unwanted searcher has left and given up. [Answer] This is going to be a bit gross, so bear with me. Have you ever gotten something embedded under your skin? Your body rejects inert matter when it's foreign. If you have something embedded in your skin, a cyst will form around it, full of pus formed by leukocytes trying to protect you from this foreign thing. The cells of your body will slowly work to bring the cyst to the surface, where it becomes a boil. When you lance and drain the boil, you have to make sure whatever foreign matter was causing the problem is also removed, so that the process doesn't just begin again. I'd combine this process with the way oysters make pearls, or how ambergris is thought to be produced by whales. Your tayan coats inert matter that it's ingested with something to make it less irritating while also having an organ which connects its stomach and skin. This organ specifically forms cysts around the object and slowly moves the object out through the tayan's skin. Since the tayan is constantly increasing its outer surface area as it grows, it never runs out of places on its skin to have a new boil, and it just pushes old "pearls" out of the way, the same way tree roots push through the ground or the way Penguino describes in his answer. This could be the weakness your hero uses to try and escape the tayan? Bonus points if people risk their lives trying to dig around tayans for treasure. [Answer] Firstly, the Tayan has evolved over millions of years just like any other creature. Over most of that period there were few (no?) metallic fusion-powered items in the environment, so it is unlikely that it would have developed any natural strategy to allow it to deal with such a thing. But it quite possibly has evolved to cope with hard/impossible to digest things. From its life-style it is more than likely that the odd rock would fall into its maw, or it would eat a creature with large indigestible fangs/armor etc. One strategy to survive this would be for it to produce a thick coating over the indigestible item, in the same way that an oyster produces a pearl. Sure, it is stuck with this thing in its stomach, but it is also growing over time so the waste items won't necessarily fill its stomach (in fact they could be used as an aid to digestion by helping grind softer items like bones to a powder - a bit like an ostrich that stores stones in its gizzard). Secondly, there is a bigger issue. Your Tayan is very large, but presumably started its life much smaller - would have eaten rodents as a child and only as an adult can eat things the size of a human. To achieve this it must have some way to remove material (dirt, rocks) that used to be where its body now is. I can imagine two options that don't require it to spit stuff up out of its maw: either it produces an extraordinarily corrosive elucidate on its outer body, so the rock/soil etc. is dissolved and washes away in solution with ground-water; or it has massive muscles that allow it to push dirt outwards and allow it to infill the space. (Or maybe a combination of both strategies). In the latter case, the ground around the Tayan would eventually start to bulge upwards a bit. See[![enter image description here](https://i.stack.imgur.com/zB96A.jpg)](https://i.stack.imgur.com/zB96A.jpg) sketch above... [Answer] What are the tentacles for? Shouldn't they be like nose hairs which stop foreign objects getting into your plant? So anything large the tentacles regard as too hard would be pushed aside which would also stop rocks falling in or tree branches etc. There should be an opening of some sort which can close as what happens when it rains? Your plant would fill up with water and drown. It would be worth checking out sea anemone for a real world example that is similar to your plant. **edit** It has two stomachs, how do they relate to each other. Cows have four I think, though not sure how they process food. I'd think the larger one does the breaking down and then the soup is passed to the next one for actual digestion. For excretion, it could sweat out unwanted compounds such as calcium which then has an affect of creating a crust between it and the soil which acts as a protective barrier. It would likely need to exude something to protect it from being eaten by worms, moles, rabbits whatever. I assume the tentacles etc are really tough because you wouldn't want someone with a knife falling in and being able to slash the inside of the Tayan. How does it stop a person stretching their arms and legs out and wedging in the throat or top of the stomach? Does the surface inside prevent this, is the victim paralysed in some way, is the victim restrained by the tentacles or passed to some other set of tentacles further down? [Answer] Here's an idea: the Tayan has some kind of organ that grinds all waste material into a watery paste. (The weapon would not be dissolved. Instead, it would be ground into a fine, powdery substance that would just end up mixed into the paste). This watery paste is taken to another organ on the outside of the creature. This organ is littered with trillions of microscopic pores that leak out this "waste paste" into the sand around it. [Answer] This seems pretty simple, there's a lot of good answers here you could combine together to handle objects of various sizes, cysts could be used for medium size for example. Overall, just mimic a lung. Lungs have almost all the same problems you're contemplating it seems? The biggest difference is no diaphragm to handle large obstructions, but if the stomach wall is musclebound then it's all the same. Small indigestible pieces would be handled the same way a lung does, with [cilia](https://en.wikipedia.org/wiki/Cilium). Just bundle up a glob and move it with tiny tentacles to the top of the mouth and out the sides. [Answer] **IT CAN SPEW INDIGESTIBLE STUFF OUT AS BAIT** My creature, which is heavily inspired by yours, has a similar problem and deals with it by turning itself into a glorified biological pit trap that uses the sand to help it hide in plain sight. I'm just going to quote a question relating to this creature. > > Its mouth remains closed, sitting just below the surface and covered in sand until it senses a victim above it. At this point, the creature's mouth opens, and the sand falls into the creature's throat, along with any hapless victims that may have been on the sand (kinda like the 'death from below' attack used by a sandworm on a spice harvester in both the trailer of the latest Dune movie and the movie itself). Tentacles within the throat reach through the sand, grabbing all living things within a certain size range (by the way, humans of all ages and sizes fall within the alforementioned size range) and ensuring that anything stuck on, carried by, or attached to the grabbed victims (such as parasites, clumps of sand, or in the case of humans, clothing or equipment) is removed. Once this is done (it typically takes just under a minute), the creature vomits everything not grabbed by the tentacles up out of its mouth and high into the sky above it and then shuts its mouth. The falling sand then lands on top of the creature's closed mouth, and the trap resets. As an added bonus, anything of value also lands atop the mouth, serving as bait for more prey. > > > Your Tayan could do something similar, setting itself up as a pit trap that situates the tentacles inside its throat, where they grab prey before the Tayan chucks everything out of its throat, to ensure prey can't escape via being spewed out with the rest of the sand. ]
[Question] [ YA fantasy novel set 350 years in the future under a corporate dictatorship which reanimates dead people to use as disposable slave soldiers. So the setup is a medical/research station orbiting a planet. The shuttles used to come and go have been stolen. Four recently reanimated, cryogenically preserved kids, and a dog, are stuck on the station and want to escape. Their plan is to crash the station into the planet. The station has some basic steering/engines/directional propulsion normally used for orbit decay correction but isn't really designed for re-entry other than being strong enough not to totally come apart if it falls out of orbit so it (and its tech) can be salvaged. The kids have access to the station's anti-grav system and the cryopreservation tank that they came out of. The way I'm thinking of doing it now is to have them hack the station to sabotage the orbit co-ordinates and activate the anti-grav. Refill their cryotank with water and get back in it (breathing kit of some cool futuristic nature - with something figured out for the dog) and close it on themselves (one of them is phobic of drowning because that's how he died so that makes for extra drama) riding out the crash in submerged zero-g. So my question is... do you think it's a) good reading/cool drama? b) plausible in fiction/worldbuilding terms? c) not cheating the unspoken rules of suspended disbelief? [Answer] # Space is not far away, staying there requires you to go really fast. As is often mentioned, the problem with atmospheric re-entry from orbit is not the distance you have to fall but the [speed you have to lose](https://what-if.xkcd.com/58/). First you need to drop orbital speed to something approaching almost nothing without hitting the atmosphere, then you need to survive the landing. If you don't drop from orbital speed you won't survive re-entry. Since you have an anti-grav system that can be MacGyvered to keep you in orbit, then used for a controlled landing. The question is whether you can get round using small maneuvering thrusters to dump that much speed. [Answer] Zombie kids! I love it! There is an infinite amount of crackingwise about being zombies that can move things along. I like your scheme except for one thing: imagine the movie. Re-entering the atmosphere, the ship glowing hot, falling apart around them and they are hiding in a wet closet comforting their scared friend. A wasted action opportunity. My humble proposal: They have cryo tank, cryo juice, water (apparently), anti gravity, space station, dog. On the way down they cool the station and slow it down by dumping the water out the front where it turns into steam. When that runs out they dump the cryo juice. The ship is falling apart around them. They pull the empty cryo tank on top of an antigravity pad, pile in and fly it out the top of the disintegrating station - or actually the station falls out from under them. Then they watch the falling station from their airship eight miles up. They put up a sail for propulsion. It can be the good ship More Brains. "It should be really cold up here." "It would be, if we weren't zombies." [Answer] Your problem is that *with traditional, present-day technology*, to stay geostationary, the station has -- depending on its altitude -- a speed of something like 10,000 km/h (this is the speed of a "typical" sattelite at 35-36,000 km). That's because we cannot nearly afford the amount of energy that it would otherwise take to keep the station "up there". If you decelerate, the station will approach and finally drop to earth, which isn't so much a problem per se (except at the very end), but it will enter the atmosphere with a velocity of, say, 5,000 or 6,000 km/h. Which, as you can imagine, is not precisely cool (pun intended) for an object that isn't explicitly built to withstand that abuse. Now, you state that there is an antigravity device of sorts. This suggests that you *do not really need* that speed. It is likely that the space station will still have a high velocity since that costs close to zero whereas keeping an antigravity device powered for years will needlessly burn a lot of energy. It does, however, not have to be that way. Thus, what the zombie kids would need to do is program the correction engines to gradually halt the station, and simultaneously turn up the antigravity device so the station stays (at least for the most part) in equilibrium. It needs not be a perfect equilibrium, the station can indeed start dropping immediately. The descent however needs to be slow enough so the manueuver engines have enough time to reduce velocity enough so the station isn't torn apart by turbulences or burns to ashes entering the atomosphere (in fact, for a more interesting story, the station probably *should* be torn apart, at least partially). Then, gradually reduce the antigravity device's output, and float to the ground. [Answer] If you have "anti-grav" you're probably not going to be crashing the station, but if you did crash it the biggest survival issue isn't the fall it's the stop at the bottom. Water as a deceleration cushion is doable, kind of, sort of, but can the container survive the impact and how much of the g-force of landing does it absorb before failure? Anything it doesn't absorb is passed on to the occupants, if the passed on load is above about 50 gees it is going to be injurious at a minimum. [Answer] Before you start you need to take an extra cloth, and/or clothing or whatever you can find to make parachutes. Clothing dispensers are probably semi automated so you can probably trick them into giving you clothes made out of suitable material. I need vinyl/canvas for a size XXXXXXXXXXXXXXXL person go! Either that or just stitch smaller ones together. You might be able to get some material from beds or other areas of the ship. Using the similar technique you might be able to fashion a hot air balloon, I am sure you can find something to heat the air with in the kitchen or maintenance area. Harder, but possible doable a homemade blimp. Using the similar materials, and breaking the water into hydogen and filling the blimp with that should give you enough lift to touch down gently. Hang glider might actually be easier, depending on what materials you have to work with. The only trick is knowing when to eject. Once the space station makes it past re-entry, then you wait some more. When you get down to 20,000ft or so jump out in parachutes. Land safely on the ground with the dog strapped to you back. [Answer] Realistically the occupants of a space station wouldn't survive reentry let alone an uncontrolled descent toward the planet surface. As the station begins to de-orbit it accelerates and generates a lot of heat when coming in contact with the atmosphere and begins to burn up. It continues to accelerate and deteriorate due to forces that the station wasn't designed to withstand such as planetary gravitation, atmospheric pressure and temperature. The G forces would paste the human occupants into the bulkheads. Impact with the planet surface would destroy any evidence of the space station or its occupants. This is of course that the re-entry angle of descent was just right otherwise the station would bounce off the atmosphere and float around for all eternity with the astronauts still alive until they run out of food and water. Realistically speaking. However if the space station were to have things like a substantial heat shielding, retro rockets, deflector shields and precise navigation ability and competent crew.. It could be doable.... Let's boldly go where no one has gone before.. As for good fiction it has been done.....KAHN!!!!!!!!!!....USS Botany Bay LLAP [Answer] **If** the station is structurally able to withstand not burning up, and not breaking apart, which I think are unlikely for a space station, then the stresses on the astronauts is potentially survivable. One serious problem would be maintaining flight stability, as any sudden twists or rolls or flips could expose the crew to very high g forces, mushing them into the walls. However, you did mention anti-grav, and attitude control jets, and if these were able to compensate for the airflows over the station, then it might be a bumpy but survivable ride. The station would decelerate constantly as it comes down, and final impact with the ground wouldn't be more than a few hundred kilometers an hour. This would not be survivable, but if your crew had access to **parachutes**, then an emergency bailout just before impact would give them good survival chances. This was a design feature for early Vostok missions, and even the Shuttle had crew egress and parachuting as a contingency plan for situations where landing might not work (losing pressure in the main tires prior to landing). ]
[Question] [ Since fire doesn't burn under water aquatic alien sophonts will use alternative technologies. The question is, which alternatives to fire can they use? I am interested in all aspects of fire, (heat, light and quick method of chemical reaction with oxygen), although they may incorporate different methods i.e. for heat, a different method is available, for light, some other possibility and some other choice for *burning* things in oxygen, if dry fire (like we have on the surface) is not available. [Answer] I'll deal with each aspect in turn. ## Heat There are a few options here. Firstly if the sophonts live in an active tectonic area they could use a hydrothermal vent. They would have to find , or create, a chimney type vent or the heat wouldn't be concentrated enough but they could then transport the heat around by piping the hot liquid from the vent in heavily insulated pipes to where it is needed. Think of it as a really hot version of a modern central heating system. **Pros** - Renewable. Once set up requires minimal input. Could possibly filter metal sulphide particles from the liquid which might be useful. **Cons** - Geographically limited. Hard to set up originally. Potentially difficult to maintain. Can contain toxic chemicals. Can't control the heat level, it is always on. Secondly They could use chemical reactions. For example they could use a group one metal reaction with water which creates, depending on the metal, something ranging from a fizzing lump of metal, Lithium (Li), to an explosion similar in strength to a depth charge, Francium(Fr). Please do try this at home. Small amounts of Potassium(K) added carefully to water should create a burst of heat, or possibly just an explosion. Placing the potassium in a sealed container will help prevent it floating away, moving around too much and will reduce the risks presented by the production of potassium hydroxide and hydrogen. Alternatively, petrol, gunpowder and some metal oxides and metals still burn underwater although they usually burn in a fairly uncontrolled way and often explode. **Pros** - Can be done anywhere. Many create metals or hydrogen as a by-product which could be useful. **Cons** - Requires raw materials such as oil or iron oxide which are quite hard to mine. Potassium is difficult and dangerous to store underwater, if it gets wet it will explode. Hard to control the reaction, once it has started you can't really stop it. I think the best option is probably bacteria. Most bacteria produce heat when they respire and this can create a decent warming effect. Try touching a well established compost heap, it will feel warm. I don't think that they will be able to produce enough heat for cooking but they could certainly keep a house warm if you lined the walls with bacteria. **Pros** - Portable. Quick to manufacture more. Once a colony has started it will keep growing. If you live near the surface the bacteria can photosynthesise so will require no feeding. Will oxidise the room. May help suppress pathogens. May be able to be harvested for food. Some bacteria produce light as well as heat so that solves two problems in one. **Cons** If you live in the deep ocean they will need a supply of minerals. Limited heat output. Can't be turned off. ## Light Some bacteria produce light. See heat for more details. Further to this, many fish and jellyfish, particularly deep sea ones, also produce light so could be used. For instance, a group of bioluminescent fish could be trapped in a glass bowl topped with netting and used as a light source. **Pros** - Portable. Gives you a family pet. **Cons** - Need feeding. Might try and escape. ## Reaction with oxygen Many reactions still work underwater, for example thermite reactions will still work to oxidise things. Magnesium will oxidise in water as will some other, similar metals. I think displacement reactions should still work so many things can still be oxidised underwater using fairly unreactive metals oxides.Overall although the simplest reaction has gone (burning) almost everything can still react with oxygen using other, slower or more difficult reactions. [Answer] You don't have to count fire out just because you're underwater. Oxygen bubbles can be collected from marine vegetation and held in an upturned bowl. A primitive underwater people could create a basic heat source by carving a deep indentation into a stone, holding it up upside down and filling it with oxygen and some flammable substance (fish oil?). This dome of oxygen and fuel would just need a spark and you would get fire. Once you understand the basic principle, you could build bigger domes for holding larger quantities of oxygen, big enough to hold kilns and forges. [Answer] # Nothing I've thought about this for a while, and the best answer is to develop a technology tree that is completely independent from fire and fire-like effects. This is a pretty radical concept, since fire was man's first tool, and indeed man's first step away from being an ape. But mer-folk, or what have you, would not realistically be able to develop a chemical or biochemical process similar to fire as their *first* technology. Fire was available to early man, who watched lightning strike and forests burn. Merfolk would hardly have many opportunities to watch sodium or lithium react with seawater. No, the underwater technology tree would start with some other root, and branch out in ways completely alien to what we have seen here on the terrestrial Earth. Mer-folk would not cook things, dry out hides, smelt metals, bake pottery or any other ancient technology that had its root in fire. [Answer] Depends what you want to use the fire for. These creatures would have no need of it to cook food, as most ocean plants can be eaten raw as well as many species of fish. If they needed light, they could potentially allow bio-luminescent creatures to grow in their settlements that would naturally light the area. Electricity for heat could be created by setting up underwater geothermal power-stations near cracked portions of the crust. [Answer] It has been theorized that humans learned about fire from lighting strikes, which set trees and such on fire. The first humans probably collected fire into bowls or other objects made of rock. Then we learned to use it for different purposes. Next we learned to create it. It would work the same way underwater. Someone mentioned vents, but there is also magma. Whoever the creatures are, they would: * first have to learn to transport it, * next to use it for basic purposes and then * how to make it themselves. Very often we forget we live in an atmosphere that reacts with different chemicals, because we have learned to control those reactions to the point we forget about them. In our atmosphere fire actually needs oxygen to survive, so our ancestors probably had to learn if they put it in an open container of wood it would simply burn the container up. If they put it in an enclosed container or stone with a lid it would go out. A stone container that had a safe opening would be best. A being who evolved living in the water would be as adapted to his environment to the extent making decisions on how to keep fire active under the water would be as natural to them as keeping it active in an oxygen atmosphere is to us. Don't always assume the problems your sentient creatures face as they evolve under the water are all that different than our ancestors did on land and look at our own solutions for correlations that may work before you go on a hunt for unorthodox solutions. Some sort of enclosed container to put magma in seems like a good idea. Maybe a partially dry cave with dried drift wood to create a source of flame would be a good place to take your magma bowl to start a fire. Your beings would almost have to be amphibians for this to work well. A lot of fish even are capable of coming temporarily to the surface, so amphibians might not be an absolute necessity. If you think this would be terribly inconvenient you might be right, but think back on how inconvenient gaining and keeping fire was for our ancestors. *Quest for Fire* is a 1981 movie you might want to look at. [Answer] Bicomponent chemical reactions should be used. If they use something, which reacts on contact with water (eg. lithium or francium) it will be viewed as an extremely dangerous, unstable substance, and could only be produced is special 'dry rooms' by acquatics wearing water filled environmental suits. The other possibility would be to use something, which only reacts with water, if heated (ignited), the thermal conductivity of water will make difficult to maintain the 'chain reaction'. So it looks like, that expect special cases, they should use a hypergolic mix, whose components don't react with water, but react with each other, when mixed. Or they could use nuclear energy. Water is a good moderator, fantastic coolant, and good radiation shield, so they won't have a problem by building a reactor. It will give a lot of heat and nice, bluish cherenkov light. ]
[Question] [ Reading through the internet and countless questions here, I learned that most Earth’s flying animals have beaks because they are lightweight and function well as a substitute to hands. Now, would it make any evolutionary sense that in my world there are sharp-teeth flying predators? Consider: * I want altitude flying, as high as peregrine falcons or vultures (so bat-like creatures are discarded because as far as I know they only fly at low altitudes); * **EDIT 2:** There was some discussion on the definition of "flying" and "gliding". To simplify, I don't want my creatures to "glide" like sugar gliders or glider lizards, but rather as prey or carrion birds; * Not beaks with teeth as some birds on Earth. Actual well defined jaw bones, like most predator mammals or crocodiles; * Quite large creature, but not trespassing the limits of weight of flying creatures of our current real world physics; Bonus points if the reasons of it being possible fits a scaled animal rather than feathered. Atmosphere and physics is Earth-like. Biological structures are also Earth-like. General anatomy and appearance can be discarded for now, let’s focus on the teeth problem. Also, I did a quick search here to see if this is duplicate but couldn’t really find one that fits my needs. Feel free to mark it as duplicate and link the answer that you think that solves this. **EDIT:** For a time parameter consider today's Earth period. **EDIT 3:** I'm creating this world's flora and fauna from scratch so stuff like great extinction events and selective pressure can be manipulated to match what I need. [Answer] The evolutionary "reason" for beaks would seem to be that they're aerodynamic, and they save weight by combining the jaw and the cutting / gripping function into a single structure. But flying creatures would have teeth if the trade-off was worth it. The function of teeth is to cut, tear and grind food, which is important if your prey is large(ish) compared to your own body; a lion couldn't swallow a gazelle whole, or if it did (like a python) it wouldn't be very mobile after eating. You can have a serrated beak, but the "teeth" can't be very big, because a beak with shark-sized teeth would already be blunt by the time it was full grown; an adult shark can replace its teeth by growing sharp new ones. Birds that eat relatively large prey have different strategies for dealing with that. If you watch a big bird eating meat, it's all tearing and whipping things around with their head, which is inefficient compared to using teeth. But because they're so mobile, they can take their prey somewhere quiet and take as long as they need, and perhaps let it rot to make it easier to chew (many birds of prey are carrion eaters). Also, birds of prey often focus on fish as those are generally less well-armored. More broadly (and obviously), flying creatures prefer flying to fighting. They're inherently more fragile, but better at escaping danger. You don't need to bite a lamb's throat out if you can drop it 3,000 feet onto a rock, and if you can kill anything that comes near you, you don't need to be able to fly away from anything. So I guess the environmental niche you're looking for is one where you need to eat fast and/or fight large prey on the ground, but also there's an advantage to flying (e.g. prey is very widely dispersed). Maybe a large, barren mountainous region, but there are sheltered migration routes running through it? Partly collapsed lava tubes or heavily wooded gorges or something, which can support prey but don't have room for a mountain lion to make a lair. [Answer] > > I want altitude flying, as high as peregrine falcons or vultures (so bat-like creatures are discarded because as far as I know they only fly at low altitudes); > > > Real flying, not gliding; > > > There's a misconception here about flying. Most of real flying is gliding. Any creature flying does as little work as possible when in the air. They glide. They use air currents. Seagulls and other large avians are fine examples. Gliding, contrary to what you may think, does allow you to rise very high. The world altitude record is, I think, some 15 km (that, 15000 meters). The main limitation for altitude in normal atmospheres would be that the density of the atmosphere will decrease, making it likely that a creature flying that high would need to build up and store whatever it breathes and could only stay at such heights for relatively short periods. But gliding is the heart of flying. Flapping your wings is not a good plan, anymore than a ground creature would survive long running everywhere. It's energy inefficient. It's for getting off the ground (at a run usually) and redirecting your flight with occasional bursts if you absolutely have to stay up. > > Not beaks with teeth as some birds on Earth. Actual well defined jaw bones, like most predator mammals or crocodiles; > > > A beak with teeth is just as effective for a predator as a well defined jaw bone. A lot of razor sharp small teeth backed up by a long hard pointy stabbing object like a beak is a pretty vicious combination. Part of the beak shape is for aerodynamic effect. A well defined jaw is a heavy object with little practical use for flight control. The more your creature relies on bite (which is implied for such a design), the more muscle they need in the jaw and weight is last thing an avian design needs. But if you insist in such a thing, go ahead. It's not written in stone that an avian creature has to have a beak. If you'd ever seen an eagle, those feet-claws are pretty deadly - I saw one attack a large loon in a lake one time and believe me, feathers and a beak are no hindrance to being a predator ! > > Quite large creature, but not trespassing the limits of weight of flying creatures of our current real world physics; > > > Like a large glider than can reach 10km in altitude and glide a distance of 1000km ? Sounds fine to me. You really need to read up on gliding to develop this idea properly, IMO. But consider - what advantage or practical evolutionary niche is gliding or flying very high giving your creature ? > > Bonus points if the reasons of it being possible fits a scaled animal rather than feathered. > > > Feathers are useful for control surfaces and insulation (cold at altitude and fat may work for ground creatures, but it's too heavy for avians to use much). Scales are fine for armor, but they're heavy (have to glide and lift into the air). It's worth noting that your basic avian predator is hardly likely to benefit from scales. They have the ability to limit their exposure to attacks from ground creatures and they can hunt in small groups (like many modern predators). Even a family or clan sized unit would be a dangerous combination for a ground creature. I think scales are not needed. A reasonably tough skin would be fine. [Answer] Short answer: yes, you can. There have been many species of flying, scaly, toothed reptiles on Earth ([pterosaurs](https://en.wikipedia.org/wiki/Pterosaur)). Not *all* of them had teeth and many apparently had some hair-like fluff, but that's optional. For aerodynamic reasons a flying creature will probably evolve towards having a pointed snout, or very narrow jaws, or a beak, but there are ways to compensate. In any case, a beak need not be a fragile thing. [Answer] # Yes and no There's no reason why not, apart from the fact that beaks became dominant to the point of exclusion for a reason. To have a toothed flyer your world could be at a much earlier stage of an evolutionary cycle, perhaps not long after a mass extinction event when there were a lot of broad niches to be refilled and a lower pressure to be perfectly optimised. It may not be a particularly efficient flyer, but it can fly. Size wise, that's a question for consideration but a mating tendency towards "biggest and strongest" could make for a big creature. In the long run the efficiency and lighter weight of the beaked flyers would likely come to dominate and displace your overweight creatures. [Answer] It is obviously possible. There were pterasaurs that reached extraordinary size and used teeth. Some types of flying dinosaurs were larger than any currently living bird. Teeth are better for eating large prey and for fighting. Size becomes a problem for flyers because weight goes up dramatically as size increases by only a little bit. At some point, you have severe limits on what can get off the ground using muscle power alone. So, let's think a little bit: we have a very large animal with teeth. It might hunt for reasonably large prey like (say) deer. It can fly, but obviously, when you consume quite a few pounds of venison, you are going to be a lot less mobile. As stated earlier, large raptors like to take large prey up to a high place where they will be left alone long enough to tear it up with their less than efficient beak. Let's say our large flyer lives in a place with plenty of reason to fly, but few or no good options for perching way out of reach. I think of maybe some of the crazy steep hills of Southeast Asia and China. No trees big enough to eat in, just hilltops where scavengers might come in and try to steal your prey, and ravines and gullies that make a lot of sense to fly over. This would be good mountain goat country, so there's your prey. Figure there are smaller scavengers/hunters like jackals or coyotes that it needs teeth to fend off, and you have a reasonable scenario. [Answer] Bats can be badasses. Behold the greater noctule. <http://www.mammalwatching.com/Palearctic/Images/Hungary/Nyctalus%20lasiopterus%20jmB.jpg> [![enter image description here](https://i.stack.imgur.com/f7tlT.jpg)](https://i.stack.imgur.com/f7tlT.jpg) These bats fly high into the air at night and catch birds on long term migrations. The birds are flying blind at night and never know what hit them. <http://www.pnas.org/content/98/17/9700.full> I say go with bats. [Answer] You said in your question > > most Earth’s flying animals have beaks because they are lightweight > > > and yet you want to put a burden on the animal by loading it with a jaw. You are therefore putting your animal on a preferential route for extinction. More weight means * more effort to fly * unbalanced flight * increased weight due to the structural changes needed to use the jaw (if you want to bite you need proper muscle mass to move the jaws, and more robust skull bones to support the muscles. All of this come at a weight) and this cost has to be payed in exchange of what? I see no advantages over beak-equipped animals. ]
[Question] [ The rotational axis of the Earth is slightly tilted now, but I would like to tilt it to 90° - something like Uranus has - and make the Earth rotate with one pole always facing one direction - eg. on summer it would be rotated to the sun, on winter away from it (that means the cold place on earth isn't always a pole), so the seasons still exist. The Earth would rotate as if it was "rolling" across a vast space disk. How could I tilt a planet's axis to 90 degrees (or as close as possible)? Is this even possible? [Answer] There aren't really enough parameters specified in the question to guide an answer (as can be seen by the variety of responses, ranging from slow mechanical interventions to planetoid collisions). In general, the Earth can be considered a very-high-efficiency gyroscope with ***monumental*** rotational momentum. @Yakk mentioned E29J energy of rotational momentum. (I assume he means 1 x 10^29 Joules). That's 100,000,000,000,000,000,000,000 Joules. When he says it would take 100 seconds of the Sun's energy output to offset the Earth's rotation, he's not talking about the energy at the surface of the earth; he's talking about all the energy you would trap if you had a shield that surrounded the entire sun, at the sun's surface, for 100 seconds. That shield would have a surface area equal to the sun, which is 12,000 times the surface area of the Earth. And the sun is actually putting out about 3.8 x 10^26 J/s, according to [NASA's Sun Fact Sheet](http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html). So, you'd actually need a little over 250 seconds of output from the Sun. If you were willing to accumulate the equivalent energy from a smaller source over a month, you could go for another star that only radiated 1/10,000th of the Sun's output (a red dwarf would be handy, I suppose). Then you'd have to collect that output (all of it), and transfer it to your Earth-tilting mechanism. Alternatively, if you wanted to use the Sun's energy, but were only willing to gather the energy near the Earth, if you were able to build a collector with a surface about the size of the Earth and put it at a Lagrange point ahead of or behind the Earth in the same orbit, then it would take only... 1,252 years to collect all the energy you'd need from the Sun. That's assuming you had 100% efficiency in all of the processes from collecting to transferring the energy, conversion into motion, etc. Make it 2,000 years, for good measure. I hadn't thought it would be necessary (or useful) to calculate the equivalent in nuclear material that would be needed to create the same effect, but just for grins, here goes: A megaton is 4 x 10^15 Joules of energy. The Sun outputs about 7.9 x 10^15 megatons of energy a day. 250 seconds' worth would be 22.9 x 10^12 megatons. That's 22.9 quadrillion megatons. I regret to inform you that the entire nuclear stockpile of all of the signatories to the Nuclear Proliferation Treaty amounts to only about 200,000 megatons. To get enough nuclear material, we'd need all of the nuclear material from 115,000,000 (yes, that's millions) Earths. So, in hard science terms, there's no obvious alternative source of energy *other* than a planetoid that would accomplish this task, and as you've heard, a planetoid would make a pretty mess of the planet in the process. Have you considered just finding one such planet and settling it? The time and energy expenditure would be miniscule in comparison... Or just make up a fantasy solar system where the planet already exists; lots of others choose this route to reach an otherwise-implausible context. [Answer] You will need to apply some sort of torque force to change the axis of rotation. The simple brute force method would be to slam a planet into the Earth (much like the moon was formed) at the proper angle to change the angle of rotation. There are a few obvious flaws to this process, including the extinction of all life on the planet, changing the speed of rotation (Earth's day was apparently 10hr long after the collision) and if you do it wrong, you may end up with the planet turning in a retrograde direction, (much like Venus) [![enter image description here](https://i.stack.imgur.com/yLdPI.jpg)](https://i.stack.imgur.com/yLdPI.jpg) *doing it wrong* A somewhat more elegant method would be to apply gravitational torque by flying asteroids past the earth. This is similar in concept to momentum exchange to change the planets orbit, (see obligatory [XKCD comic](https://what-if.xkcd.com/146/)), but flying the asteroids at high angles to the ecliptic would provide the torque at an angle to the axis. The main issue with this method is that the Moon is stabilizing the Earths axial tilt, but using the asteroids to move the Moon out of the way first then allows for some astro engineering to change the axial tilt of the Earth. [Answer] You might like to read ["How to spin a planet" from Paul Birch](http://www.orionsarm.com/fm_store/SpinAPlanet.pdf). The basic idea is to accelerate (or decelerate) some large mass against the planet's surface. Due to the principle *actio = reactio* you'll accelerate the planet in the opposite direction, causing it to spin / change its axis. Note that IMO the concept presented in the paper (yes, that's a paper!) above is a bit too complex for your case, because changing the rotation *axis* means you'd need to dynamically alter the path of the reaction mass / high velocity projectiles around the sun. A simpler setup uses an acceleration ring (think a hyperloop track) around the planet. Energy comes from (lots of) solar panels. The correct placement of that ring is crucial and requires good knowledge of the inertia of the planet. Using multiple rings could be an option here. Correctly placed they'd allow for free definition of the planet's rotation axis (and speed of course). [Answer] It's also possible to change a planet's axis (although slightly) using earthquakes [Japan Earthquake 2011](http://www.nasa.gov/topics/earth/features/japanquake/earth20110314.html "Japan Earthquake 2011") Strong enough earthquakes at strategic locations and times might well be enough to rock the earth into a drastically changed axial tilt. Admittedly, this was a magnitude 9.0 earthquake, which moved the axis of the earth by about 3 inches. Hollywood would make it work... [Answer] Building up on Pete's answer, the solution would be to trigger a coordination of massive earthquakes. Millions or billions of them. The easiest way to trigger massive earthquakes is to blow up a lot of thermonuclear bombs strategically placed deeply underground (not necessarily in land, could be even in deep oceanic trenches). Preferably some very big ones like Tsar bombs. Perhaps you could detonate a lot of them simultaneously to exploit constructive and destructive sismic wave patterns. After some millions or billions of such detonations, you would be able to gradually tilt the Earth's rotation axis until you achieve the desired 90 degrees tilt. [Answer] There are a few things going on here. While the earth rotates on a 24h daily cycle, it also precesses on a 22kyear cycle. That means the axis of rotation changes and makes a complete circle. Given these mechanics, you'll have to strip the body of all rotational momentum, so that it is not spinning or precessing, then using whatever mechanism that countered the existing momentum apply it in the desired direction of rotation. You may be able to accomplish it more efficiently without bringing momentum zero, but you'd have to very precisely apply momentum in the exactly correct direction and timing. Failure to do so would work against you. For an idea of the power required, consider the angular momentum of a solid sphere. [Answer] The two step method: 1. Put long stick in equator. (Think space elevator) 2. Apply force to space end of stick (while *not* connected to ground!) This is much easier when the planet doesn't spin, so you might want to spin it down first. Then the tiniest force will set the pole moving to the equator. Stop that motion when the pole has moved 90 degrees. Spin planet up again after that. You *did* save the rotational energy, didn't you? [Answer] You smack it at an acute angle with a big rock that's going really fast. Then you have to do it again, and again, and again, every time it tilts back because that's only going to effect the outer layers and the core rotation is going to drag those back into alignment. Meanwhile the torque you are applying to tilt the crust and the friction between the mantle and core that is being created are going to either rip the planet apart or heat it molten and that's without factoring in the direct heating from the impacts. Oh and the Moon would have to go as it stablises the existing rotation too. You apply constant gravitational torque either using direct gravity manipulation if you have the technology or by flying huge rocks just *past* the planet you want to tilt, you'd have to dump the Moon anyway or it would capture a lot of the rocks so you may as well cut it apart and use it *for* the rocks instead. You'd have to apply it for a really long time to get the core to align and again the waste energy from the torque will either destroy the world or evaporate it. *If* you *can* use direct gravity manipulation you could stop the world spinning altogether, Moon too, (you also have to stop it in it's orbital track too or it will pick up rotational energy from it's orbital velocity) without breaking it. Then once all motion died down, you could tell by the total collapse of the magnetic field, spin the system back up in a new direction. Of course you then have to bring in a new atmosphere and oceans since the solar winds have stripped the original ones off while there was no magnetic field to protect it. If you can only directly effect the crust you may have to exceed the normal Roche Limit of the world (which you can if you have it in an artificial gravity field) to get the core spun up again since it's the size of Mars and the only thing inducing it to move is surface friction between the liquid outer core and the mantle. This solution still has the potential of boiling the planet but that's not an impossibly bad thing this time around. ]
[Question] [ **TL:DR** A brain is turned into mush, destroyed, then 98% of the organ is replaced with other brain tissue. Can that 2% account for memories shared between both brains? Can the brain remember things that happened to the other brain? The new brain is 2% old brain and 98% new brain. Story: Character A is a self made immortal organism, a girl who learned the magic needed to modify her body both consciously and automatically. Character A has the ability to modify every cell of her body, 300 years ago she learned bio magic and covered herself with nearly indestructible and regenerating solid plate armor, she has no face and no mouth. Her head looks like an obsidian helmet but is actually made of light sensitive cells which work as eyes. Character A can sometimes grow bio weapons out of her body, like toxic smoke, explosives and flammable acid that burns win contact with water. Most importantly she doesn't age, doesn't get cancer or any disease. Character A does not have a face or facial muscles, she could build one at any time but for amusement when she is asked what she looks like, she opens her face helmet showing exposed veins, fat tissue and nerves, no bones, she doesn't have bones in her face or skull, just the shell armor. Character A is living in another more primitive world but comes from our modern world, she has deep knowledge of political and military history, that's why she has worked for kings and emperors as a military commander over the centuries. Character A was alive for more than three hundred years, but let herself be killed in battle for personal reasons. The Empire needs Character A alive for their military agenda, Character A is a strong warrior, a good tactician and the best propaganda ever. Character A has the same importance as Jesus, a living Jesus made of flesh. The Empire's magicians have learned how to activate the subconscious magic powers that regenerate character A and bring her back to life, After the damage which killed Character A the regeneration takes 2 years to bring her back to life, as compared to the 3 weeks needed to regenerate or modify 45kg of tissue while she was alive. For my story I need character A to wake up with the mentality of a newborn baby who needs to learn everything from the beginning, a dangerous and lethal newborn baby in the body of an immortal murder machine with centuries worth of muscle memory of killing people. As character A grows to the mental age of 7, I need some of her old memories to come back, is it possible or do I need to handwave it with something? [Answer] Better practice your handwaving. Scientific knowledge of exactly how memories are stored is incomplete at best, but it appears to be spread through significant parts of the cortex and distributed. There was an old joke among neurosurgeons, when they'd make an incision or otherwise touch the brain, "There goes yesterday's ham sandwich," because so often they'd find very minor deficits after such small damages. It's very unreasonable, however, to think that a mere 2% surviving tissue from the original brain will store any significant memories, or with any completeness. Also, it's worth noting that "muscle memory" is no such thing -- it's conditioned reflex, which resides mainly in the motor centers of the brain and to a much lesser extent in the reflex processing in the spinal cord. Your immortal killing machine of a person wouldn't even be a real baby -- a baby has several months of in-womb neural connection forming before birth, such that they can at least mostly control "autonomic" systems like digestion and breathing, where a freshly recreated brain, if truly grown from "blank" tissue, would lack even that. One possible way around is if the brain were regrown *with the same neural connections* that it had before the, um, accident. This would require a nearly molecular level 3D record of everything inside the skull, at a minimum, and technology far beyond anything we can even explain today -- or magic that works in mysterious ways -- but there's some reason to believe that at least some reflex and memory are encoded in the connections between brain cells. If those connections can be recreated, much of memory might return with them. [Answer] Based on other answers, it seems impossible that the brain recovers. But your character has taken that into consideration, seeing as she can alter her biology at will. Unknown to everyone but herself, she made a secondary memory storage in her body, to be able to restore her memories in case of significant damage to her brain. The way they triggered her regeneration, the memory restoration is not activated, because they didn't know about it, but she later stumbles on these other memories stored somewhere in her body. [Answer] Memory is a complex issue. It combines chemical composition, the amount and distance of linked neurons and constant feedbackloops that remain firing electric signals to maintain a type of behaviour/memory, like liking a particular soda. To further complicate things the brain is constantly modifying itself and can have immense potential on small portions of it. This plasticity of the brain means that a mailman will have an increased area for navigation and area memory, an area that will shrink and give over neurons to other tasks if you stop being a mailman and start doing other tasks. A more extreme example I personally knew someone with a mental problem who died of cancer. Then when they did an autopsy they found out that during his cancer one half of his brain had basically rotten away completely, yet he never showed any signs that he was deteriorating mentally as somehow the remaining half of his brain took over functions. We can try to look at forms of dementia, but the problem is that only a few key neurons need to disappear to disable an entire neuron chain linked to a particular set of memories. If the neuron mass is reconstructed with all links intact you may find that many memories are intact. So we can't say "if with dementia the brain shrinks by X% then X% of memories are gone". We don't know exactly what neurons are responsible for exact memories, but what we do know is that one memory isn't just stored in one place. It is a dance between many neurons all over your brain to retrieve, process, visualize and eventually experience the memory. If your memory neurons are intact but the set of neurons that steer their activation aren't there the memory can't be retrieved and your brain will basically start overwriting the memory as it repurposes them for other tasks. Or if the connections to neurons that process it aren't there the memory can't be relived. [Answer] **The 2% regenerates the rest.** Your immortal invulnerable super can regenerate. Regeneration requires a template of what must be regenerated and that template includes memories. Having been dead for a while her regeneration is a little lacking, as you say. But she has 2% of the original brain and that 2% gradually grows back some of what was lost. It is not exactly growing back, since she has a newborn baby brain in that space. The 2% original brain colonizes that brain with regenerated cells based on the original. The recreation is not perfect. Regenerated tissue is close to the original but not exact. Some memories are missing and many are hazy and muddled. She remembers allowing herself to die but cannot remember why she chose that. She remembers showing people her face of nasty veins, fat tissue and nerves but wonders why she ever thought that was amusing. [Answer] **As character A grows to the mental age of 7, I need some of her old memories to come back, is it possible or do I need to handwave it with something?** In these 7 years, the brain of Character A will have changed drastically. Children use and shape their brain a lot ! the 2% remnant memories you are talking about, precious military skills for the Empire, are completely outside the scope of a 7 year old ! These areas will not fit in and therefore fade out and become rewired. I'm afraid your reborn hero (who fled to a foreign primitive place to escape ?) not only looses her freedom again at 7, she'll have to be reprogrammed as well. And 7 years is very early. The painfull, torturous attempt may just fail. Chance is, history repeats ! The whole effort does not bring her back as a soldier for the Empire, but she retains all her powers, and she'll *not* be loyal.. she may flee again.. [Answer] > > For my story I need character A to wake up with the mentality of a newborn baby who needs to learn everything from the beginning, a dangerous and lethal newborn baby in the body of an immortal murder machine with centuries worth of muscle memory of killing people. > > > As character A grows to the mental age of 7, I need some of her old memories to come back, is it possible or do I need to handwave it with something? > > > Its a really good idea, but before asking how to achieve it, we need to check some of these points. **"Muscle memory" doesn't mean what you seem to think** Its a shorthand term for complex physical skills that don't (subjectively) appear to involve thought. For example, walking, riding a bicycle, throwing a dart at the bullseye. We kind of learn and trust our bodies, to "know" how to do things like this, or so it seems, even though the learning is really a brain skill. That's muscle memory. Your characters muscle memory could make her have prodigious skill with physical objects (movement, weapons) but they won't choose how she uses those. That's more about her instincts - the instinct to react with lethal force, the instinct to hide or ambush, all her other choices. **If they wake up with the "mentality of a newborn baby", what exactly is retained and what isn't?** Do they retain knowledge of weapons for example, how to dismantle a gun? Can they dismantle a gun under pressure without understanding how they knew it? Do they remember tactics, and what instincts if any need to come back? Do they remember personal history/events, when you say "some of her old memories come back"? Also, just as telling, what stuff **doesn't** come back? **How much influence does nurture have, to rewrite anything** Usually whatever ones instincts and memories, the person one grows up to be, is heavily influenced by role models, upbringing, and lessons learned during this life. Your character may have old memories but they have to come back in the context of an entire life of new experiences and lessons. For example, if they were brought up by peacelovers, or fanatics seeking war, would that influence them? If the old person had seen animals as utilities for devising weapons, but the new one had been given a puppy as a pet at age 3....? **The impact of experience, and returning abilities/memories, will be very different 2nd time around** Killing a person age 150 is very different from blasting your primary social connection into sludge at age 2 or age 9, because of an uncontrolled brief tantrum over ice cream. Will her outburstings, traumatise her? What lessons will they sear into her? She has no idea what it means, either. For children, "Am I okay as a person" is a huge issue. (Think peer pressure and social media or bullying feedback, and that's for children virtually the same as any other by comparison. As children its a huge deal to be okay with oneself) So the new person may develop negative beliefs about herself or her abilities, deep down, that were never in the old person. What happens? **So.....** If you can clarify some of these, I can expand this, and try to actually answer based on the new information. For now I can only point out what's needed, to try answering. [Answer] *"Character A is a self made immortal organism, a girl who learned the magic needed to modify her body both consciously and automatically."* **So, magic.** Part of the magical spell(s) that gives her these abilities is to regenerate her memories as well as her body. Easy peasy. OR *"The Empire's magicians have learned how to activate the subconscious magic powers that regenerate character A and bring her back to life..."* AND they create a spell which helps her get her memories back too. How? Create an "ether" of some kind where all of mankind's memories are stored. If you're already using magic, you're in handwave country and you're all good. [Answer] **Memories can be stored in all cells of the body, not only in brain cells.** > > For my story I need character A to wake up with the mentality of a newborn baby who needs to learn everything from the beginning, a dangerous and lethal newborn baby in the body of an immortal murder machine with centuries worth of muscle memory of killing people. > > > "Muscle memory" may not be as unrealistic as it sounds. Although it's a figure of speech used to refer to procedural memory, it actually might exist in the literal sense - not necessarily that memory is preserved in muscle, but that certain memories can be stored in all cells of the body. As a key point, there have been patients who received organ transplants (ex: kidney or heart), and later recalled memories from their donors' lives. These included their donors' hobbies, preferences, and even personalities. I remember hearing about a transplant recipient who developed a preference for fast food and motorcycles after his surgery... he later discovered that these were his donor's favorites. Do a quick Google search and you'll see many scientific studies on this. Below is just one such example. <https://pubmed.ncbi.nlm.nih.gov/31739081/> Memory preservation is seen in other instances as well. Research on monarch butterfly migration shows that these butterflies migrate over three generations. The memory of the places they've been as well as their destinations are passed down to their offspring in their DNA. Realize that DNA is encoded in every single cell in the body... not just brain cells. There also may be certain memories stored in mitochondrial DNA, assuming a person's nucleus gets damaged. Whether or not there is another explanation for these memory transfers, you could certainly use them as the basis for a fictional work. Have your character regain memories that were stored in somatic (body) cells other than the destroyed brain tissue. ]
[Question] [ In a near future setting (technology has progressed more or less at the current pace) would it be possible to have a genetically modified tree that has both the density and textile strength of [Schinopsis\_brasiliensis](https://en.wikipedia.org/wiki/Schinopsis_brasiliensis) (see also this answer in regard to it's exceptional qualities [Creating wood actually as hard as granite](https://worldbuilding.stackexchange.com/a/80135/75264)) AND fast growing properties like [Paulownia](https://en.wikipedia.org/wiki/Paulownia) (one of the fastest growing hardwoods)? Note that: > > Paulownia grown on plantations generally has widely spaced growth rings, meaning that it is soft and of little value; wood with close growth rings is harder and of higher value.[citation needed] Paulownia is extremely fast growing; up to 20 feet in one year when young. Some species of plantation Paulownia can be harvested for saw timber in as little as five years. > > > Would 'fast growing' necessarily be mutually exclusive with 'extremely dense and with high bending strength' for a tree? Generally fast growing hardwoods have large rings. This leads to lower density and tensile weakness. On the contrary trees (even of the same species) with thinner rings are denser, with higher tensile strength but grow more slowly, usually due to less favourable climatic conditions. The purpose of the company engineering the tree is to have a naturally fast growing hardwood that can sustain construction. To be shaped while growing. Imagine treehouses, bridges, monuments. [Living architecture](https://www.sciencedirect.com/science/article/pii/S2095263517300353) in general but brought more to the extreme (the living tree structure) and to a bigger scale than the examples in the link. Economic sustainability is not an issue. The purpose is not to have wood as construction material like with this method: [Wood made denser and stronger](https://www.nature.com/articles/d41586-018-01371-0). The tree must be alive and growing while being shaped. Merging of trees, even of different species is fine. Grafting is also appliable. But the main structure of the tree should be of the genetically modified species (of which the company holds the rights). [Answer] So here's the thing: all trees of a given size, under similar environmental conditions, can lay down about the same amount of material in a season. They're all basically leveraging the same building blocks in the form of their chloroplasts, and whilst there are small variations in photosynthetic efficiencies under some circumstances, there's no such thing as a substantially superior photosynthesiser, and that's what you'd need to solve your particular requirements. Given your near future tech level, I'm going to assume that creating a better chloroplast remains science fiction, so something else has to be done instead. You might consider some way of artificially nourishing the tree... force feeding it, effectively, and giving it the leafy equivalent of growth hormones. This sounds like something that would go alongside shaping and guiding living wood to form the sort of structures you want. By combining artificially increasing growth rates with a way to suppress the tree's tendency to lay down lower density wood during the summer seasons might enable you to force-grow dense timber. This seems likely to be quite a complex and expensive sort of task, with special groves of engineering trees surrounded by their support infrastructure and nutrient tanks which would have to keep operating for decades, most likely. Do note that this sort of living structure will not have the same sort of density as the compressed would you linked above; the tree has its own internal infrastructure in the form of vascular tissues that are necessarily low density in order to let stuff through. --- As an alternative though, consider a different kind of architecture that doesn't rely so much on heavy, solid structures. I've always been a fan of banyan trees... they've an interesting structure that involves column-like aerial roots, and they can start out life as an epiphyte that grows over an existing tree and effectively smothers and crushes it. They can grow extremely large... here's a photo of the Great Banyan: [![Great Banyan](https://i.stack.imgur.com/G3j9S.jpg)](https://i.stack.imgur.com/G3j9S.jpg) This is a *single tree* with the largest canopy of any tree in the world at ~1.5 hectares. With a bit of persuasion, you could see how the horizontal branches and vertical prop roots could be bent into a useful shape upon which lightweight tensile structures could be built. Sure, it wouldn't have much in common with modern architecture, but why tie yourself to the same old designs as everyone else? Treehouses are awesome, fact. Consider, for example, the [living root bridges](https://en.wikipedia.org/wiki/Living_root_bridge) that can be found in northeast India. They are often made from roots of ficus trees, not necessarily the same as the great banyan above, but similar. The roots are guided and plaited an interwoven with other structural materials over a period of years to construct things like this: [![Living root bridge](https://i.stack.imgur.com/WibCh.jpg)](https://i.stack.imgur.com/WibCh.jpg) Suitable domestication and genetic engineering of appropriate species could allow for large and elaborate living structures to be created, on and around existing architecture or trees that could be used as scaffolding. [Answer] The hard part of wood is the darker part of the rings -- this is the slower growth wood, that's higher in lignin. The faster a tree grows, the more of the light colored, low density, softer wood is laid down between the dark, dense, hard rings. Therefore, in general, a tree that grows very fast produces softer wood (balsa is a prime example -- balsa trees grow to harvest size in about five years, and produce wood so soft and light it's pretty nearly useless for anything other than flotation, naturally grown insulation, and model airplane frames). Trees that produce very hard wood, by contrast (teak, ironwood and so forth) are generally very slow growing, laying down a minimum of the light, soft wood between dark, hard rings. While it is surely possible to engineer (or selectively breed) trees for rapid growth, doing so will defeat the purpose of producing stronger, heavier wood (though you will get better strength to weight ratio, as is the case with fast-growing poplar, birch, and softwood species like fir and spruce). To get the kind of wood you seem to be after, you'd need to engineer your tree to continuously grow the high density wood, rather than lay down softer material and harder material in cycles (usually a year due to seasonal variations). This might be managed to give faster growth than natural teak or ironwood, but will unavoidably be slower growing than poplars farmed for pulp or paulownia for saw timber. [Answer] > > Would 'fast growing' necessarily be mutually exclusive with 'extremely dense and with high bending strength' for a tree? > > > Short answer: yes, the faster a tree grows, the weaker the wood. There will always be a tradeoff between how fast you want it to grow and how hard you want it to be (the tree). Long answer: just about nothing is truly impossible in biology. The growth rates and hardness of woods we see today are purely due to evolution in the wild and some selection from humans over the past few centuries. With sufficient genetic manipulation, you could force a tree to grow fast and hard, but it would require enormous amounts of energy to sustain, and I doubt you'd ever really obtain the speed of growth of Paulownia with the hardness of Schinopsis. Another angle of attack that you could take that could work better: the (very heavily genetically engineered) tree grows fast, and is shapeable into a house or whatever structure you want, but is quite weak. But once you expose it to certain conditions (very cold temperatures, or high wind, or perhaps a parasite), the bark toughens immensely, creating a very rigid structure. This would mean that this particular tree is now stuck in this conformation, so you would no longer be able to grow an additional story to your tree apartment block. This is still very much the realm of pure theory, but it is more biologically plausible and doesn't run head first into hardness/speed of growth tradeoff. [Answer] **Chronomutant** > > Occasionally, trees will produce more than one ring in a year. The > extra ring is called a false ring and it can be the result of drought > stress in the middle of a growing season. > > > <https://www.fs.fed.us/rm/highelevationwhitepines/Education/science-inquire.htm> Your fast growing trees have optimal conditions all the time. But their clock has been hacked - they are genetically engineered to think the hard times come every 2 weeks. They power down. Winter lasts 2 days and then they power back up. These trees lay down dozens of hard rings in a growing season. They do not grow as fast as their unmodified relatives who lay down lots of soft white wood, but they are still fast. [Answer] Duncan wood is produce from the Duncanoia tree. This is a heavily genetically engineered wood with the following modifications: * The entire photosynthesis cycle was heavily modified, bringing light conversion efficiency up from the paltry few percent to almost 70% in full sunlight. Researchers continue to tweak this, and have been getting about 1% improvement per decade now. * The tree has much larger sap vessels. This is needed to transport the sugars through out the growing parts of the tree. * Stomata have permeable membranes that allow CO2 to pass inward, but reduce water traveling outward. * The tree has highly alkaline sap. This disolves silicon dioxide out of native rock and sand. The dissolved silica forms a complex silicon oxide cellulose crosslinked complex. This complex accounts for the strength of Duncan Wood. In most varieties, pore space in the heart wood is filled with this material too, but it's not as well organized. Researchers would like to either eliminate this, resulting in lower density wood, or get it organized, giving better strength for the same cross section. Downsides: * Temperature regulation is more difficult for the Duncanoia tree. Optimum growth is restricted to temperatures from about 12C to 25C, with photosynthesis dropping rapidly on either side. This is another subject to much ongoing reseearch. * Because the leaves are far more efficient, Dunconia is best grown in an atmosphere with 4-6% CO2. On most planets this results in the tree being only grown under large domes, where the air can be enriched with CO2 from degrading compost or fossil fuels. Grown in the open it is only a few times more efficient than other common trees. Dunconia is widely used as a mid stage plant in terraforming high CO2 worlds, as well as ones with active volcanos. * Duncanonia needs a continuous supply of silicates to grow strong wood. Optimum tree plantations need to be on a substrate is is mostly sand so that as the tree 'mines' the sand the whole area settles evenly. Drainage can be a problem as plantations sink. [Answer] ## Short answer is No *At least not to any significant degree* The other answers have already said THAT you get hard and soft rings, but not WHY. Hard rings come from having less growth of vascular tissues. While the tree is growing quickly it needs a lot of hollow vascular tissue to pump water and nutrients between the leaves and roots. So, if a tree is growing quickly, its wood must be soft, but if it is growing slowly, its wood may be hard. This excludes the possibility of a hard wood coming from a fast growing tree. When doing your research it is also important to know that hardwood is not the same as a hard wood. Hardwood trees are any species of deciduous tree and softwood refers to any species of coniferous trees, but many hardwoods are actually very soft. You can see [HERE](https://www.alansfactoryoutlet.com/hubfs/75-types-of-wood-ranked-by-janka-hardness-3_print-poster-1.pdf) that Paulownia is in fact one of the softest woods in the world. ## Use Industrial Engineering instead of Genetic Engineering While biology may be limited in how hard it can grow wood, there are certain man-made materials derived from wood that are extraordinarily hard. Nanocellulose can be produced by extracting and crystalizing the cellulose from the wood of any plant into one of the toughest materials known to man. Because the production of Nanocellulose begins with the pulverisation of the wood, the amount of starting vascular tissue is irrelevant. Fast growing woods may be less dense, but because they have more vascular space, they can put on mass faster than a slow growing harder wood. So, you can grow softwoods quickly, then process them into a substance that is even tougher than the hardest of hardwoods. **While this may be a less glamorous solution than growable buildings, it is much more practical for a number of reasons:** Many countries do not allow you to own the intellectual rights to a plant, and those that do tend to come with a lot of caveats. It is much easier to patent a material produced from a plant, than a plant itself. Living buildings are a bad business model. When you buy land, you want to wait the least amount of time possible to have a usable building on it, and once you have a building, you want it to be permanent. As a person who wants to buy a building, you want the growing to happen offsite so you don't have to wait 10+ years to have a place to work/live, and once you have it, you want it to not be growing or else the rooms will be changing shapes and sizes causing flat surfaces to tilt, and furniture to have to be regularly replaced as the sizes of rooms change. It is also much more precise. Manufactured materials can be molded into any shape you need down to the millimeter. While you can get certain plants to follow along the shape of a superstructure, plant growth is not very precise. Even genetic clones tend to have a lot of variance; so, your floors will never be level, your doorways never uniform. These little details can change the value of a building by a very large margin. [Answer] Yes and no Not going to an extensive answer here, but it is an interesting topic, so 2 cents on it As already mentioned energy inflow to trees is one of the limiting factors for the growth, and artificial nourishment may improve the situation. However, it does not necessarily mean a 10fold increase, as the internal structure of a tree is a limiting factor again. The tissue which produces the wood is a thin sheet between the bark and the core/wood itself. Bamboo and some other trees have different growing structures. So it may be possible to increase the surface of that tissue which grows, let's say if we shape that growing tissue on some primer, which goes like a spiral as an example, we can 10 fold the surface area, where wood is produced, and thus if we nourish it enough, it may be 10fold wood production increase. Back to that bamboo cheater - it is hollow, and from material science, we do know that a pipe, or T-beams, etc are not much weaker than a solid equivalent but are significantly lighter, and that is exactly one of the bamboo tricks. So as for your structures be solid may be a wasteful excess, which is another way to say we can increase the surface area of productive cells in all sort of ways - it can be a hollow bone-like structure with channels and internally on walls of the mesh are cells which make wood and gain strength over time and then die out. So it all about increasing centers of growth and at the same time give the energy and building blocks to the cells. It may be possible to make the wood itself be stronger and here where actual genetics may be involved in change the cell structure and what wood or more precisely which kind of composite material they do produce. (Cells may be elongated beyond natural necessities, produce carbon nanotubes to reinforce the structure, some polymers which soak the wood and solidify under some conditions, etc) So there no single trick to use, but a set of approaches, maybe to the point u would not call it natural wood after looking at the material. Maybe most promising is the increase of the surface area of the tissue which produces wood and artificial nourishment. Those may increase the speed of the mass production, also give a preliminary shape to construction which then grows and increases strength. Primer can be another wood as an example - sheets of wood, wires/ropes of wood, or other materials, on which u spray cells and a cover for them and then pump nourishment through that structure. Or primer structure can be much more sophisticated one and then the sky is the limit, or not, depends, but with it, u would be able to grow any shape in a year or half-year - but again it would play mostly 2-3 notes - nourishment and increase surface area and predetermined shape. Again set of approaches, technology can give u what u want, but it won't be a single genetic trick. Also, there still will be some limits, one of the bottlenecks may be the speed of lignin forming, and others, it is the field of chemistry, those are polymers which have to be oriented properly, stitched together, etc and where constants of reaction speed play determining role and no genetics can help u, it not necessarily a problem and it looks like it is not a problem, but it needs to keep in mind that limits, bottlenecks, may come from the most basic processes happening in the thing. I would say with a good tech u can grow anything in a year and less, with less perfect ones in few years. [Answer] I stopped reading after this amusing tidbit: "In a near future setting (technology has progressed more or less at the current pace) would it be possible to have " I can promise you this: for the next two years at least, with the idiotic leadership we have today, we aren't getting past covid. And by the time we do, half of us will be dead. Then you can have whatever type of tree you like. ]
[Question] [ I have a walled city in a medieval RPG setting. It's out in the middle of a desert and has an impossibly efficient means of acquiring water and producing food off of farmland inside the walls (magic is involved), so its geographical location and internal self-sufficiency make it a very daunting target to attack. However, because of the monsters that infest the world, the walls need to be patrolled during times of peace in order to keep the monsters out; and during the rare times of war, there need to be enough soldiers to effectively defend the walls against determined human attackers. The walls are between 20-30 feet (6-9 meters) tall, there's no moat or ditch outside the walls; and the walls are, at a bare minimum, 12 miles (20 kilometers, 20,000 meters) long. Assume that the existence of magic doesn't dramatically change the realities of combat, and that you need roughly the same number of defenders to defend the same chunk of wall against the same number of attackers. With this in mind, how many soldiers would be needed to **patrol** the walls, and how many would be needed to **defend** the walls? EDIT: I suppose I should clarify what they would be defending *against*. Assume that the defenders have to protect against an army of, say, 20,000 men, or one man per every meter of wall. The walls provide an advantage, but that's a lot of wall to target for various tricks, ruses and attacks. EDIT2: The attackers are actively attacking the walls, and there is nothing of value outside them, so the defenders have no reason to give up the advantages of the walls. Since the city is self-sufficient, trying to starve out the defenders won't work. The only option for the attackers, then, is to storm the city, either through brute force or trickery. EDIT3: Of the monsters that try to get in, the ones that are most able to scale the walls are probably about human sized, and have comparable levels of stealthiness, and aren't *much* more dangerous than an armed soldier... but they operate exclusively at night. [Answer] ## Patroling The normal patrolling of a wall can be parallelised: substantial fortifications are invariably broken up by regular watchtowers and the guards in one watchtower are responsible for patrolling the the wall between themselves and the next watchtower over. How far apart the watchtowers are dictates how challenging a job that is. How long would it take a sneaky monster to climb your wall? A world-record-level human [can climb](https://en.wikipedia.org/wiki/Speed_climbing) 15 metres in less than six seconds, but that is up a wall that, by fortification standards, is pretty poor (as in has a lot of strong holds). Your generals need to (deliberately or inadvertently) choose a 'minimum climb time', which is the time that, as long as any given stretch of wall is observed at least that frequently, any climbing monsters will be seen before they reach the top. Let's say five minutes for that. Humans walk at a [preferred speed](https://en.wikipedia.org/wiki/Preferred_walking_speed) of about 1.4m/s, but wall patrol guards will need to stop regularly to actually look out over the wall, so let's say maybe 1m/s patrolling speed. So in five minutes a patrolling guard will cover 300m of wall. Guards should certainly patrol in pairs at least, and could only realistically be on duty a third of the time, so that patrol actually consists of six men, or 50m of wall per guard, continuously guarded. In terms of how big an *army* you need to maintain that level of watch, the proportion of the whole army comprised of frontline guards (the [tooth-to-tail ratio](https://en.wikipedia.org/wiki/Tooth-to-tail_ratio) might be as low as 50% when you factor in both officers and support staff (armourers, grooms, quartermasters, trainers, etc). So that suggests maybe 800-1000 men to continuously patrol 20km of wall. Clearly, you can swing this number wildly by changing the patrol frequency: double the minimum-climb-time, half the guard, and so forth. This quantifies just how much benefit there is to be gained from making the wall more impenetrable. Increasing the time to half a day (cough GoT Wall) makes the ratio as low as 3.5km per guard, which makes guarding a 500km-long wall with under a thousand men *just about* feasible (although the Night's Watch is far from an efficient fighting force). ## Defending When defending a wall, the game changes completely, but remember that the patrolling game must *also* continue as well, so the patrolling manpower is an absolute minimum. Here we care about the numerical advantage that the wall (and any other factors like quality of training, nutrition, morale, etc) gives the defenders over the attackers. Crudely, if the numerical advantage is 5 and the defending general puts one soldier on the wall opposite every five attackers on the ground, the defenders should win. Those defenders need to be in addition to the patrolling guards who need to *keep* patrolling in order to detect any new incursion attempts. What's a realistic number for the numerical advantage? The exterior terrain you've described is pretty formidable: an army without very strong logistic support is going to collapse pretty quickly without natural water and food, so the most sensible offensive strategy is probably to march up and attack straight away, especially given that a seige is impractical. So the army will be tired and will not have had the opportunity to construct extensive artillery or siege equipment, they'll have had to bring any rams, ladders or towers with them from some distance. I don't think a numerical advantage of ten to one is unreasonable, in which case a reserve force of 2000 *frontline* soldiers would be sufficient. Of course in reality when the attackers move in you would also call up all your armourers and officers (so the T3R of that 2,000 can be much higher) and any civilian militia as well, but they would be contingency. TLDR: a standing army of 3000 would be more than sufficient to continuously patrol a 20km wall, and probably to defend it against a 20k attacker, as long as it was well trained and equipped and had solid morale. [Answer] **Wall dogs.** This answer is only for the monster question. Your wall is patrolled by wall dogs. These dogs actually spend their time at the foot of the wall, roaming in packs. They are trained and come for food to their food stations. Each pack has a section of wall of about 1 km. The wall dogs are really for the monsters. A monster which comes out of the desert at night is going to be detected by the dogs and they will be all over it before it starts climbing the wall. They will be barking too (the ones that don't have a mouth full of monster) and human handlers will come to help. Because of the dogs you only need a couple of humans every km. Dog senses are better for detecting monster incursions. Dogs are much cheaper than humans and they are more expendable. Wall dogs will be brought into their kennels in case of a siege. They are fearless but would be wasted against a bunch of armed men. --- thinking more - this is D&D! So if you encounter the dogs, there will be a chance that a non-dog creature will be in their pack, working with them. The non-dogs will have been raised with dogs and will think they are dogs. I like displacer beasts for this. [Answer] # Monsters and Armies are different problems. With individual monsters, you probably want to catch all or most individuals. A leak rate of 20% or 30% is likely unacceptable. So you need enough troops on the wall, 24/7, to catch them. Call it a double patrol every 50m, plus a small squad every 400m or so -- enough to arrive at the midway point in a minute, even running in armor. Quadruple that for 24/7 duty and we're talking about 6,000 troops. You need fewer troops on a nice, sunny day, but the garrison should be able to cope with rain and snow. Go with the worst weather assumption. Against an army, you have the benefit of **inner lines.** The purpose of fortifications is not to be impenetrable, it is to buy time for a small number of defenders until the main defensive force arrives at the trouble spot, and to increase the effectiveness of the defenders. If a few scouts climb the wall, so what? They could just as well disguise themselvers as traders and bribe the gate watch. An army of 20,000 with baggage and a siege train would do well to do 15 km in a day. By contrast, the defenders need one or two hours from the center of the city to the wall. So it should be possible for the defenders to match any attempt of the invaders at concentrating their force. The key question, then, how many people do you need on the walls to block the invaders below? Look at the numbers for [Chateau Gaillard](https://en.wikipedia.org/wiki/Siege_of_Ch%C3%A2teau_Gaillard), or the [1187 siege](https://en.wikipedia.org/wiki/Siege_of_Jerusalem_(1187)) of Jerusalem (even if that ended in a capture). [Answer] Perhaps not directly applicable to the city you have described, but the burghs might be a good data point for medieval manning levels. The burghs were a network of fortifications through Wessex and later England in the 10th century. Farmland was outside the walls, but the farmers would retreat to the walls to protect against raids, and the burghs were also used as strong points during wars. The *Burghal Hidage* states: > > For the maintenance and defence of an acre’s breadth of wall sixteen hides are required. If every hide is represented by one man, then every pole of wall can be manned by four men. Then for the maintenance of twenty poles of wall eighty hides are required. > > > A hide was a patch of land of no fixed size used for administrative purposes. A pole is about 5m. So the requirement is a little less than one man per metre to defend the wall (and the hide should also provide enough income to pay for the maintenance, in addition to other obligations such as bridge maintenance). These men would be local fyrd - not full time soldiers, but still fairly well armed and trained. The walls they are defending would be a combination of earthen ditch, stone facings or wall, and wooden palisade, all together 2-3m high. That's not to say you would expect to see the garrison spaced out 1.2m apart all the way round the wall before a fight - probably they would be denser facing the enemy, much sparser round the back, and there would be a reserve who didn't start on the wall at all. Rather it is a rule of thumb for the adequate manning of the wall. So I would say that a 20km wall requires 16000 men to man it properly. That said, a force of 20000 men would have very little hope of success against say 10000 atop a wall, so you can get away with under-manning it. But if a larger enemy turns up and you have 10000 defenders, then the wall is too long, and you will benefit from shortening it. Perhaps by falling back to a shorter inner wall after making the attacker pay for gaining the outer one. [Answer] In peacetime you need sufficient guards within running distance of where a climber, or pack of climbers, will summit the wall after it is spotted. You need two shifts of night guards and all the infrastructure to support them. Work done on the wall to make it harder to climb (precision stone cutting, installing an iron facing, just making it taller, etc) pays a major benefit as fewer guards are now needed. When besieged you need archers (or ballistae) with fire-arrows (or bolts) sufficient to destroy the invaders supply of wood. without wood there will be no siege engines or tunneling sappers. and no hope of a successful siege. [Answer] What shape is your city? It could be irregular, rectangular, square, octagonal, round, or have a lot of other shapes. The more regular and equal sided the city is, the more land can be enclosed for the same length of wall. Thus there can be more soldiers supported by the city to defend the wall. If the city is perfectly circular and has wall 12 miles or 20 kilometers long, it will have a radius of 1.909 miles or 3.1831 kilometers, and an area of 11.4488 square miles or 31.8310 square kilometers. That would be the maximum possible area within walls 12 miles or 20 kilometers long, and will have to support a sufficiently large number of defenders using realistic medieval farming techniques, and/or futuristic food producing technology, and/or magic. I discuss efficient food production technologies in my answer here: [Giving Tolkien Architecture a Reality Check: Dwarvish Kingdoms](https://worldbuilding.stackexchange.com/questions/100380/giving-tolkien-architecture-a-reality-check-dwarvish-kingdoms/100413#100413)[1](https://worldbuilding.stackexchange.com/questions/100380/giving-tolkien-architecture-a-reality-check-dwarvish-kingdoms/100413#100413) which is based on ckersch's answer to: [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)[2](https://worldbuilding.stackexchange.com/questions/9582/how-many-people-can-you-feed-per-square-kilometer-of-farmland) My answers to this question: [How much space would a city need within a ringwall to survive for an indefinite period of time?](https://worldbuilding.stackexchange.com/questions/173709/how-much-space-would-a-city-need-within-a-ringwall-to-survive-for-an-indefinite/173752#173752)[3](https://worldbuilding.stackexchange.com/questions/173709/how-much-space-would-a-city-need-within-a-ringwall-to-survive-for-an-indefinite/173752#173752) And this question: [Build an impregnable fortress in the middle ages with modern technology](https://worldbuilding.stackexchange.com/questions/127177/build-an-impregnable-fortress-in-the-middle-ages-with-modern-technology)[4](https://worldbuilding.stackexchange.com/questions/127177/build-an-impregnable-fortress-in-the-middle-ages-with-modern-technology) Discuss the design of an impregnable fortress or city in the middle ages and how to support the number of defenders needed. Experts in medieval warfare should be able to calculate the number of defenders needed to defend against particular threats. [Answer] Patrolling depends largely on visibility. Two blokes can walk up with a ladder, put it up against the wall and get over in half a minute. Someone more athletic could throw a grappling hook over with similar effects. So basically you've got to have fairly continuous visual coverage of the approach. In daytime, one guard per mile might be fine. Then heavy rain falls, visibility a hundred yards and you need a lot more people. Thick fog, or a moonless night, mean you have to start relying on patrols and hearing. A medieval army is extremely unlikely to storm defended fortifications at any odds. That would be suicidal. More likely they will undermine the walls, reduce them with siege engines, use rams to go through the gates, or try other methods (fiery projectiles, plague rats, or, more simply, agents inside the city). [Answer] Patrolling: The rule for a detection patrol is very simple. (assuming your absolutely need to stop 100% of intruders) You figure out the quickest possible intrusion. Then you space your patrols at intervals of 1/2 that time. This ensures that a breach is detected even it one patrol is missing/delayed/stupid. Example: if it takes an enemy 10 minutes to breach your wall, then a patrol every 5 minutes is needed. If it will take your monster 10 seconds to breach the wall, then you need a patrol every 5 seconds, and someone needs to fire the wall architect! With a relatively easily breachable "Wall", for example a chain-link fence, this effectively means you need continuous surveillance from watchtowers suitably spaced to cover every inch of perimeter. In real life, walls do not serve as impregnable barriers, but merely as obstacles. They hinder and delay intruders, both when entering and leaving. Make them look for easier targets. Prevent them from feeling secure once they have entered, as escape is also hindered. Make it harder for stolen items to be carried off safely. *Most* defensive walls actually fall in this category, I suspect yours will too. If you make it so that a monster trying to enter is more likely to get killed than get away with a prey, that monster will die off of starvation. Even if it does get in sometimes. Harsh, but that's the real world. As for siege defense: A barrier wall for keeping intruders out is *very* unsuitable for army-scale defense, and vice versa. A good army defense wall will have multiple sally ports, and tons of access stairways/ramps on the inside, and ammo points, and evacuation routes. All of which make its utility as an intrusion wall compromised. I strongly advise that the "anti pest" wall be further out from the military wall. Much lower/smaller/cheaper. And very regularly patrolled, or even permanently occupied. The space between your army wall and the nuisance wall is a *great* place to house and train your army! ]
[Question] [ I'm currently trying to set up an underwater race in my world—merpeople if you will—and I'm trying to figure out how their city would look. I'm basing their religion and lifestyle on native civilizations such as Inuits, or some Native American tribes, but I also want them to be sedentary. What materials available in the deep waters could be used to make houses? [Answer] Cegfault took the most obvious material: stone. Let me offer a couple more. **Coral** Houses could be grown through coral polyp husbandry. Officially, the material is *calcium carbonate.* Houses of nearly any size could be made through this method, though is would be slow. However, with a bit of engineering, walls, floors, and roofs can be built this way. Thick coral would be a reasonable protection from break-in. **Kelp and sea grass** Agriculture isn't just for food! Cultivated sea grasses could be planted, and woven as they grow to create sturdy walls. This solution would be excellent for [tipi](https://en.wikipedia.org/wiki/Tipi) style domiciles. Or, if weaving walls isn't your cup of tea, you could cultivate personal groves of sea grass, then trim a path into the grove and rooms within the grove (think "corn maze"). **Caves in ocean trenches** There are [oceanic trenches](https://en.wikipedia.org/wiki/Oceanic_trench) all over the planet. The wonderful thing about trenches, is that they provides *sides.* Especially the deep ones. Caves can be hewn out of the sides. Hole households could be inside, so long as the local current isn't so strong that it can erode the cave mouth. This solution would work anywhere there was a reasonably steep, somewhat verticalish surface (the sides of volcanic mountains are especially prized for their central heating). [Answer] **Whalebone.** Those bones are big. They can be found on the ocean floor. [![whale fall](https://i.stack.imgur.com/P3Klu.png)](https://i.stack.imgur.com/P3Klu.png) <https://en.wikipedia.org/wiki/Whale_fall> Ancient Siberians made huts out of mammoth bones. [source](http://www.egyptsearch.com/forums/ultimatebb.cgi?ubb=get_topic;f=15;t=010540;p=1) [![mammoth bone hut](https://i.stack.imgur.com/F0yao.jpg)](https://i.stack.imgur.com/F0yao.jpg) And people do make huts out of whalebone found on the beach. <https://www.pinterest.com/pin/223280094000002936> [![whalebone hut](https://i.stack.imgur.com/fFvYm.jpg)](https://i.stack.imgur.com/fFvYm.jpg) Probably there would be a lot more whale bones available to your merpeople than can be found on land. Plus bone huts offer fun writing possibilities. Besides whalebones, there can be other comparably large or larger bones used to make the buildings... [Answer] I like the Coral husbandry of JBH and carving out of cave/cliff walls. But I can add one more option. A civilization may advance to a point where they need to use energy sources. Best energy source maybe geothermal vents and underwater volcanoes. this could provide energy for future technological development. Now if your "merfolk" could harness this, they would build structures around these energy sources, maybe control the spewing lava to form the structure around it. So, you could create an igneous rock/obsidian structure. You could augment these structures with other building materials. Unfortunately, where you would find these energy source may not be where you would also find coral or sea grasses. Sedimentary rock, such as sandstone would be readily available, or any other strong and tough rock that would hold up to currents, external forces and quakes that would most definitely accompany a volcano. Maybe you can control the water chemistry enough to grow massive salt crystals to incorporate into your structures. This would be decorative in nature only and would be fairly difficult to do in this environment, but would make a great "temple" of some kind if your civilization advanced to a Aztec level society. [Answer] Assuming the mer-people can breathe through water, and mirroring Native American style homes, then it would be practical to form homes out of sedimentary rocks at the bottom of the sea. These would likely resemble the homes of [cliff dwellers](https://en.wikipedia.org/wiki/Cliff_dwelling) or [adobe-style homes](https://en.wikipedia.org/wiki/Adobe). Most rock at the bottom of the sea is sedimentary; this makes it dense and hard. A creature advanced enough, with the intelligence of human civilization, could go through the stone age with tools available in the ocean, and using such tools chisel out homes out of the rock formations at the bottom of the sea. It would not be too far off from Native American style homes. As far as the Inuits that you mention, the [Igloo Construction](https://en.wikipedia.org/wiki/Igloo#Construction) would be a better shape for the water pressure of the ocean, but would probably be easier made as being chiselled-out into the stone (like the cliff dwellers), as mining rock only to re-form it would be difficult, especially because any type of mortar would be difficult (but not impossible) to make inside water. [Answer] So bit of an unusual suggestion but if they're an Arctic species ice! Ice floats are always bigger below the surface and carving ice is definitely possible plus you can make some truly beautiful things, personally I think an upside-down igloo would be really cool and added bonus if they're whale based and need air you can carve air pockets. Plus imagine waking up in a beautiful shining house, never get up past noon again! ]
[Question] [ In my setting the known worlds have recently begun coming out of a [medieval stasis](http://tvtropes.org/pmwiki/pmwiki.php/Main/MedievalStasis) after about two thousand years; the lucky worlds at least. Prior to the event that destroyed their technology and all the knowledge pertaining to it, the peoples possessed a common spoken and written language. With ships traversing the ether once reconnecting worlds, these scattered people are interacting once more. Would sharing a written language be enough to make the "common tongue" at least somewhat comprehensible between worlds or would the written form have drifted as well? [Answer] If the Chinese language and culture is any indication, then no, having a common written language does not, in fact, reduce lingual drift. Many of the dialects in Chinese are completely mutually unintelligible, despite sharing a written language. However, due to the shared written language, and the fact that most of the characters retain more or less the original meaning across lingual groups, the fact that they happen to pronounce the characters differently does not prevent them from successfully communicating in most situations. This worked out because the Chinese use symbols or glyphs for the characters where the symbol has a specific meaning (occasionally two), irregardless of pronounciation. [Here](https://en.wikipedia.org/wiki/Varieties_of_Chinese) is a sampling of information about it. [Answer] Perhaps an even better example than Chinese or Arabic would be Latin after the fall of the western Roman Empire. Latin diverged into the Romance language family - French, Spanish, &c - which despite obvious similarities are mutually unintelligible, and heavily influenced other languages such as English. Yet during all the time in which these languages diverged, Latin was the common written language, there was a body of classical learning in that language which educated persons were expected to be familiar with, and there was a common institution - the Church - which used (and to some extent still uses) that language in its affairs. The OP might use something similar: the languages of the common folk have diverged, but educated people acquire the "Old Tongue" as a second language, and so are able to communicate. [Answer] Writing won't be sufficient, given how Latin and Arabic diverged over time. [This article](http://www.economist.com/blogs/johnson/2013/06/arabic) about the dialects of Arabic is informative, and makes a comparison between early Latin diverging into French, Spanish, Portuguese, Italian, and Arabic now. Basically, Since the Islamic conquests Arabic has become mutually unintelligible between different regions which remained isolated from each other for long enough to evolve into unique dialects. Often contemporary Arabic speakers will struggle or fail to understand each other without reverting to classical Arabic, just as Catholics in medieval Europe used [Medieval Latin](https://en.wikipedia.org/wiki/Medieval_Latin) (again different from [Eclesiastical Latin](https://en.wikipedia.org/wiki/Ecclesiastical_Latin)) for formal communication. Perhaps the most interesting point made in the first article is that Arabic speakers will often revert to a common dialect, which is often Egyptian given the influence of Egyptian media in the Arab world. And this suggests that mass media, with radio, television, and the internet, has a potent effect. Not necessarily to unify dialects, but rather to make a common language more accessible. Also worth noting the evolution of different accents between [American and British English](http://www.smithsonianmag.com/smithsonian-institution/when-did-Americans-Lose-British-accents-ask-smithsonian-180955291/?no-ist). Which is the first step towards a new language. Isolated accents become dialects, isolated dialects become languages. Of course that has come full circle with the domination of American English given American media influence, but it's still a decent case study. > > People back in England noted the quirky new ways Americans were > speaking English within a generation of the colonists’ arrival. Over > time, the changes went beyond accent to include different words and > grammatical structures, adding up to a new dialect. Dialects have two > main causes. The first is isolation; early colonists had only sporadic > contact with the mother country. The second is exposure to other > languages, and the colonists came into contact with Native American > languages, mariners’ Indian English pidgin and other settlers, who > spoke Dutch, Swedish, French and Spanish. All of these languages > influenced American English, as did the English-speaking colonists’ > origins in different parts of England, Wales and Scotland. > > > The speed at which this happens, and severity of language drift, will depend entirely on issues like immigration, prevalence of education, speed of transport, language institutions and restrictions (like the notoriously protectionist [Academie Francaise](https://en.wikipedia.org/wiki/Acad%C3%A9mie_fran%C3%A7aise)) and how otherwise isolated communities are. Common written language isn't enough to prevent linguistic drift. Keep in mind that Ottoman Turkey used the Arabic alphabet for centuries for Turkish, and Iran still uses the Arabic alphabet for Farsi. This complicates matters more, since neither language originated in Arabic, nor suited using the Alphabet. A common alphabet certainly isn't good enough in that case! [Answer] The example of [Arabic](https://en.wikipedia.org/wiki/Varieties_of_Arabic) suggests a common written language is not sufficient. Arabic speakers normally learn their local vernacular variety of the language as their first language, then learn Modern Standard Arabic and Classical Arabic in school. The Quran is written in Classical Arabic, and although that's a sacred text to the majority of Arabic speakers, it hasn't prevented the vernacular languages from evolving to the point where some of them aren't mutually comprehensible. That's only taken a thousand years, and travel throughout the Arabic-speaking world has been possible throughout that time, except for a few breaks for wars. However, there have always been other languages around to influence Arabic vernaculars. If the known worlds of your setting had only a single language, that might slow down changes, but the longer time period and complete isolation make it seem very unlikely that there would be mutual comprehensibility. [Answer] English has been a written language for all of its life, yet Old English (up to about 1150 CE) may as well be a foreign language to anyone by an academic specialist, and even Middle English (to 1470 CE) is challenging to read and understand. Of course, the fact that English has a phonetic written language, rather than a written language based on ideograms has something to do with that evolution as well. The time depth of the Indo-European language family that can just barely be discerned by professional linguists, in on the order of 5,000 years (albeit without writing for the first couple thousand years on average). A thousand years is plenty long enough to give rise to mutual unintelligibility, although the absence of a competing completely different language to influence the evolution of these separated languages would slow dialect formation, and for the time periods when they had audio recordings, this could stabilize the language in ways that mere writing would not. But, it is also not widely recognized how high a share of linguistic drift comes through contact with other languages (often as substrate languages) and from the intentional efforts of two distinct populations to bring about language schism for the purpose of distinguishing in groups from out groups. In the absence of such pressures, e.g., in Iceland, languages evolve much more slowly than they would otherwise. Lots of language change attributed to random linguistic drift isn't actually random at all. Also, some long term trends in phonetic drift tend to happen in one particular direction. For example, a given set of vowels is more likely to drift to another particular set of vowels than any other vowels. So, some of the phonetic shifts would likely happen in parallel and once you grasped where a sister language was in phonetic shifts and learned to make the substitutions, learning to understand the sister language might be a lot easier than it would seem otherwise, particularly for basic daily life words that are more stable over time where the lexical content would change only a little after adjusting for phonetic drift in an orderly fashion. In your scenario, any professional linguist could probably figure out that the languages of the known world have a common ancestor and even estimate how long ago that was. Also, language learning might be much easier than learning a language from an unrelated language family. But, an average person who knew one language could probably not understand another with separation at a time depth in multiple thousands of years. [Answer] Even with a common written language and close communication, the actual meanings of some English words differ between America and Britain right now. For example, the word "literally" in the U.S. means almost exactly the opposite of what it means in Britain. An American can say "Dude, you are literally killing me," and nobody calls 911. Even symbols can develop dramatically different meanings based on events. The holy swastika has been revered in India for thousands of years, but its use by Nazi Germany has made it a symbol of hatred and evil in the West. You could have a lot of fun with local variations on which innocent words from the shared language have become heinous insults on some planet by pure historical accident. Generally, a written language will be the formal version of the language, while people communicate in everyday life in the vernacular, or colloquial version. As others have said, when these separated colonies get back in touch, they may be able to make themselves understood to some extent in writing, because the formal version of a language changes more slowly than the spoken version. ]
[Question] [ I see a lot of truly alien aliens in the world of worldbuilding, but one thing that almost every single alien species has similar is their technological development. Pretty cut and dry, the technological development for an alien species seems to be ancient age, stone age, bronze age, dark age, medieval era, renaissance, new age and (the yet achieved here) Space age. As far as I can tell, no matter how I design the species, there is no way to their development differ from earths. So I must ask, is the development for a species set in stone? [Answer] Yes and no. Some stages of progress are inevitable. For instance: 1. You don't use tools at all. 2. You make tools from things which are just lying about, like sticks and stones for weapons or lumps of clay for a cup. 3. You figure out that flint is a better stone for tools than quartzite is, so you starting digging flint out of the ground. Hurrah, you've invented mining. 4. You figure out that clay heated in a fire is harder and lasts longer than the sun-dried stuff. Hurrah, you've invented pottery. On the other hand, the **environment** of your alien species is going to be a big factor. Dolphins and octopuses, for instance, are never going to invent pottery, because they live underwater and thus can't do the simplest version (firing pots in a bonfire) to kickstart that whole line of technology. So anywhere the chemistry doesn't or can't work the way ours does will not be able to duplicate some of our achievements (fire won't burn underwater). Or they may discover something earlier in their development, For instance fires burn hotter and longer in high oxygen atmospheres, so observing what heat does to things may be a higher priority for them, and they invent smelting or kilns quicker than we did. The environment includes the other creatures you share the planet with. If you have no equivalent of cattle and horses, you don't invent the plough, the stagecoach or horse-drawn artillery. Animal power was a major factor in many of Earth's civilisations and technological developments. Next, there is the **anatomy and physiology** of your aliens themselves. For instance, if they have wings and can fly (and obey the laws of physics), they will be severely restricted in how much they can carry and still take off. A bird-alien can't cover itself in chainmail or platemail unless it wants to be stuck on the ground. Bird-aliens may therefore neglect aspects of metallurgy in favour of trying to create tough but light textiles to act as armour. If they are carnivores, they are not going to invent horticulture or arable farming early like we did. They'll probably invent pastoralism (herding animals) pretty quickly, but it may be a long time before they decide to start growing fodder for their domestic animals. And if they are not growing plants in their equivalent of the Stone Age, then they are not going to kickstart a whole bunch of other industries - anything which relies on plant fibres or plant oils, for instance. So they might invent knitting, wool weaving and felt making because they keep sheep, but they won't have canvas for sailcloth & tents or linen for clothes, because they never grew flax for edible seeds and oil and thus never figured out its other properties. Finally, their **psychology**. If they are a truly territorial species, by which mean territoriality in the [biological sense of the word](https://en.wikipedia.org/wiki/Territory_(animal)) they don't travel and they don't invent trade. They stick within their territory boundaries and react with violence when strangers turn up. Territories are *small*, globally speaking. A territory might be the size of farm or small national park, but it is never going to be the size of a country. The aliens can't invent any technological development which relies on resources outside their territory. So they can't have a bronze age unless they've got both copper and tin on their particular patch of land. [Answer] **No**. Technological development stems from two aspects of human behavior: a **desire for power** and the **use of tools** to achieve tasks. Most technological developments can be attributed to these factors. Power comes in many forms. There is power over our environment. Building shelter and a fire keeps us warm despite the cold winter. There is power over animals, harnessing them to gain more power elsewhere, for military or economic purposes. There is power over others, governing them or defeating them in battle. Tool development is even simpler. This ranges from a sharpened stick to the high tech machinery we have today. We make tools to gain power: power over others, over animals, over the environment, and so on. The more we discovered, the more our lust for power grew. Better tools made their way quickly between neighbors, as people were unwilling to see others have an advantage. And groups were always looking to improve their creations, so as to have power over others without that tool. This competitive flare led to the advancement of our species as a whole (more or less). So what's all this talk about? Well, in order to have a radically different society without this progress, we must **remove or suppress these traits** from our alien creature. Our creature would then have the following features: * Not competitive. This of course means that the creature is not competing for food, habitats, mates, etc. Which leads me to: * Everything they need is provided. Natural resources, food, water, shelter. The creature does not need to *try*, if you will. Most of human tech has been to fulfill some shortage in society: easier food, take land from others, fighting off creatures and diseases, you name it. * Entirely peaceful. This is easily achieved with the above two, but worth stating nonetheless. The creature should not have to, or desire to fight other creatures or themselves. * A spark of intelligence. So far we've described a society of amiable pacifists. That may well "succeed" in surviving, but it makes a boring story. So direct their intelligence towards once field you want them to specialize in. Since everything is provided for, they can devote all of their time and effort to perfecting that art. This may progress them through human technology somewhat (say, stone tools if they are into material artwork), Their end goal is not the same as our own though, so they would not progress in the same manner as we have. [Answer] The Great Library of Alexandria featured several designs for mechanical devices like steam engines, and it is widely speculated that the Industrial Revolution could have begun in Ptolemaic Egypt, rather than 1700's Britain. However, the politics of the day dictated that knowledge was restricted to the elites, and the common folk didn't see much in it for them to preserve the scripts of the Great Library when it burned down. Human labor was also very cheap back then, so there wasn't as much of a perceived need to automate (whereas some historians point to Europe's historically low population as an impetus for industrial development as a means to compete). So, in theory, if there was an analogue to the Great Library, the scientists of the day could embark on research into information theory and discrete mathematics, essentially leapfrogging industrialization into an information age, all at once. [Answer] ## No It is not set in stone, but there are good reasons why we see what we see. First of all - we do not have tech tree for our technology ourselves. I mean tech tree as some model which someone can work with. We do not have [science](https://en.wikipedia.org/wiki/Science) where tech trees are objects of interest. * Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe. As we do not have systematized knowledge about our tech tree as whole - from stone to chips, we can't produce other valid tech trees, similar to ours, and we can't produce other tech trees, for other alien civilization. Producing tech for alien civilizations needs also evolution models - to determine groups, kinds, chemistry, shapes, etc of those aliens. And to determine capabilities of different alien forms, we also need good astrophysical models - to determine and classify possibly environments for those aliens, in details enough to create valid models of alien life. We have none of above for ourselves, and as result, we(as humanity) can't generate valid models for aliens anything. As an example, a question - is it possibly for some aliens in ocean world, being ocean creatures to have industrial like technology, not biotechnology. Or which options are best for them, which environment they should have (how deep ocean have to be, which geology they have, the planet composition, etc). That everything will be highly speculative. In this situation, referring to history is a good move, because we know it worked for us once, and how it did, there is some variation in that process in our history. But it has to be accepted as an open question, like a symbol, x-variable, rather than how it could be really done for them. As we do not have models for tech we can't change them, test something, determine trough experimentation rules of development, boundaries of possibilities, classify those possibilities - etc, same stuff we do for bulk data. At the moment we even do not have that raw data available to operate for small groups, and we do not have results of researches of such groups about that data, which some writer can rely on or use. As *rmrfslash* pointed in his answer, with The Great Library of Alexandria situation, we are in the same situation, maybe it is better some areas, thanks for good peoples and [OSF](https://en.wikipedia.org/wiki/Open_Software_Foundation) and such, but, in most cases we have the same situation or even a worse one in most cases in recent time (you might not have access to library, and never had in any way, but if you did what is described in that library, you will be punished by law - short description of patenting system) Another **big** reason - it's very hard to make a valid system, not one man work. As an example [Copenhagen Suborbitals](https://en.wikipedia.org/wiki/Copenhagen_Suborbitals) - they trying to make rockets. Do we have the tech for what they wish to achieve, yes we do, so ...? They have youtube channel [Copenhagen Suborbitals](https://www.youtube.com/channel/UCPzFMJIsp2fOQ_ic5a_zXTA), where they show their testing's, talks about what they do in researching of manufacturing processes - show some bits of that getting knowledge for them self, not for humanity because humanity knows that already, ... khm, I'll better stop here. So valid models are not expected for a long time. [Answer] Yes, but not the ones in particular you said. The order is... Stone Age > Bronze Age > Iron Age > Industrial Revolution > Digital Age > Solar Age > etc. Dark Ages and Renaissances come from reaching a pinnacle, falling, and then recovering. Stone, Bronze, Iron have to do primary material of war which is also the dominant factor in the age which are pretty much set in stone due to the ease with which to find and use these material. Industrial and Digital age comes from revolutions in conceptions of how to build things and then communicate. The Industrial age comes first because the digital age require mass production of products and the industrial revolution could come before or after the iron age, but the industrial revolution before the iron age wouldn't have a big impact since bronze and copper doesn't lend itself to mass production like iron does due to it's softness and such. The "Space age" or is obviously going to be divided up between the period when there is practicaly a global government, Solar Age is when we start colonizing the solar system, and from there multi-star system and eventually the galaxy and possibly other galaxies. These are all logical progressions so they must come in this order. You can have multiple dark ages and renaisances and have regression into previous ages, but once a concept is wide spread it is hard to get rid of it so dark ages refer more to cultural and further technological collapse which wouldn't effect them in anything other than the ability to get infrastructure to continue on, but once you have anything like that you'd just pick up where you left off pretty much. [Answer] ***Short Answer:*** The primary literary role of "aliens" in the vast majority of science fiction is to represent different aspects of humanity.As such, neither the authors nor readers have much incentive to create truly novel technologies, save as a plot gimmick. But realistically, while natural "laws" would constrain the evolution of both organisms and their technology so that the differences would not be random and inexplainable, variations in environment, contingency and the history of the alien world would produce different organisms and different technologies. If nothing else, aliens would behaviorally place different emphasis on the same technologies than humans would. Given how much diversity existed in human technologies back before globalization really took off 400 years ago, clearly aliens would be even more diverse. Neither physical or behavioral (whether genetic or learned) biological evolution follows any predestined path and since technology is just a behavior, it to is subject to natural selection, and likewise has no predestined path. TL;DR - don't you have something better to do on a Saturday morning? There is no such thing as predetermined evolution...period. "Natural Selection" is really the flow of energy through the biosphere where the formation of complex molecules and structures produces more entropy than if the energy just hit and radiated out. The form of organisms is created by the outward pressure of this flow of energy. Variations that consume more energy and dump out more entropy get selected. But while more entropy producing forms are selected for, the particular forms possible both from historical constraints and the exact flow of energy into and entropy out of the environment, produces a vast number of possible forms. Not to mention "black swan" events like asteroid impacts. Technology in evolutionary terms is a behavior of organisms and behaviors are just as subject to natural selection regardless of ***whether those behaviors arise from genes or are learned.*** Natural selection operates on the phenotypes, the structures and behaviors that interact with environment, and not the genotype i.e. the genes, epigenetic factors and neural and other learning structures. So, technology evolves via natural selection and as such shows all the effects of variation, diversity, and contingency all compressed entropic flow, just like biological structures. You can see this quite clearly in human technology. We think of primitive hunter-gathers of using chipped flint tools and all to commonly we assume all flint tools are pretty much the same. But archeologist recognize tens of thousands of variations all subtly as distinct as different species and subspecies. Sadly, our best preserved knowledge of past technology is overwhelmingly in the area of weapons. Even restricted to one weapon class such as "sword" we see vast diversity of swords, each form requiring different individual techniques as well as different tactics, strategies, social and political organization for the groups that use them. The famous English longbow archers, were unique in Europe and largely unique in the world. Most of the rest of the world who weren't horse riding nomads used crossbows. The degree of training required to master the bow required the wielder either be part of culture (like nomads) wherein all men trained to the bow, or it required a dedicated subculture, which showed up at least briefly in a Hindu cast. The English had longbows not owing to any special technical knowledge nor a simple fluke. Instead, the anomalous existence of a large population of free, land owing yeoman in Wales and West England created conditions in which a subculture could specialize from childhood in the weapon. After bowmen kicked the French's backside for over a century, the French king, IIRC, Charles II, used distributions of lands, tax policies and feudal cohesion to produce a French yeomanry who specialized in the bow. While never as good as the English longbow men, they were good enough to blunt the English advantage. The longbow is just one of several examples of technologies that require a particular history, culture, political system and even tax structure, to become a powerful weapon. If you throw in an alien environment and sentients, its unlikely you find longbowmen a Yor-gath. Technology is restricted by physical laws, and that will funnel their form to follow their function regardless of what planet the technology evolved on. But that also applies to the organisms themselves. There is likely to be recognizable technology on alien worlds but like flint tools in humans, the closer one looks the more diversity one sees. Alien physiology could make a huge differences as well. The arteries of the vertebrates on earth have no valves in them. A serious puncture or severing of an artery ***anywhere in the body*** will cause death. All sharp or penetrating human weapons from flint points to .50cal BFG rounds all seek to punch relative narrow but very deep wounds anywhere in the body possible with the major goal of severing an artery. But if alien major lifeforms had valves in their arteries, cutting the artery would not necessarily be a fatal or even disabling wound. If a human pumped such an alien warrior with arrows or even bullets, it would just piss him off. Such aliens would likely not evolve stabbing or puncturing weapons but instead slashing, smashing, hooking, netting etc. Primitive human hunters puncture their prey, usually not fatally, and then jog after the fleeing animal until it bleeds out. Aliens with arterial valves would bring down prey forcefully and immediately. They might rely more on traps or they might hunt deer-like prey by attaching some fatiguing or entangling device to a non-lethal barb which would cause the creature to be unable so encumbered or tangled as to not be able flee or flee fast. (We used to hunt whales this way, in many different cultures, barb them with floats so the drag exhausted them and prevented them from diving.) Some kind of barbed, weighted net or lasso might take the place of both bow and sword. When they moved on to chemical or other non muscle powered weapons, they would be more interest in crushing or concussive effects than they would penetration. Instead of evolving the handgoone first, they might go for some kind of flamethrower. Major environment would have a lot of effects. Low grav world like Mars, (assuming they could retain atmosphere etc) would tilt the advantage towards armor, supported against gravity, against weapons, i.e. it would cost less energy to carry a unit of biological or technological armor than it than on earth but the power of weapons, most of which work perpendicular to gravity, would remain the same. An armored knight on Mars could wear armor 2-3 times as thick as on earth but swing of his sword would have the same or (owing to traction issues) less power. If we bundled all this together with aliens with valves in their arteries and lower gravity favoring heavier armor, their entire hunting and weapon's technology would depend on superficial attacks of prey and foes e.g. setting the on fire, entangling and immobilizing etc. The type of hunting they could do when in small primitive units, and the types of weapons they would have to use when in large scale coalition warfare, would feedback into their culture in many different ways, including altering their non-weapon technologies, which would feedback... and so on. However, having said all that, its likely has their technology grew more powerful, it would begin to differentiate less. A nuke wouldn't behave differently on low-grav world than on earth. It would kill by heat, blast and radiation. We can see the same effects even today with powered technology replacing muscles both in constructive and destructive work. As we say in Texas, a small woman with a gun is just a dangerous a huge man with a gun. Females still lag in infantry warfare where muscles still play a big role but they just as lethal as fighter pilots or radar technicians in bowls of a warship. Once we have real exoskeleton mech suits, even infantry won't matter anymore. The same leveling would appear in regards to aliens. If we encounter them when their physiology dominates their technology (pre-industrial) they will look much different but if we encounter them in space, its likely the technological differences will not be as significant. Alien social structure springing from biology would also have effects. For example, some sort of high trust, low internal competition hive-like species would never fallen in anti-nuclear power hysteria, chemophobia, "all-natural" superstitions etc because they wouldn't have the internal and incessant scramble for social status dominance that humans do. Before you flame me: The National Science Academies of all developed nations have concluded that: 1) Anthrogenic gasses are forcing the climate, 2) Nuclear power can be safely utilized to provide dependable, lowest-carbon energy almost everywhere in the world. (Heck, organic food has literally killed more people in the last 30 years than nuclear power has in nearly 80. 3) Genetically modified foods are safe both for human consumption and the environment. 4) "All-natural" does not mean either beneficial or harmless. Just as clearly, it’s the same social and political demographic that thought Marxism, Eugenics, Freudianism etc were great ideas as well. The same demographics that were dangerous technophiles for over a century years are now luddites. The only thing that remains constant is that if they win the political debate, they rule society. Currently, they are causing massive distortions in our technology decisions, with all that implies and if their bet the whole farm on alternative energy doesn't work out to prevent global warming, well... A hive species might show up to hothouse planet Earth with humans extinct or knocked back to savagery and poke around and think, "they had the technology to stop it all, why didn't they use it." Such technological decisions would be inexplicable to them. … or, if you don't like that scenario just use the conventional Hollywood inverted narrative. Brave, altruistic and definitely not greedy or power crazed activist and far seeing politicians, who descend intellectually from a subclass who has always been right in the end for centuries,take heed of the climatologist and try to use appropriate technology, "sustainability" etc to head of the problem only to be stymied by people so greed, stupid and short sighted that they can honestly be analogized to those crypto-Nazis who deny the Holocaust in WWII ever happened. Run away global warming or at least climate "change" has the same effect as above. Either scenario is not one hive aliens would understand to because their primary mode of competition would be hive-to-hive and not individual-to-individual and coalition vs coalition. It would appear to the xeno-archeologist that humans reached a high level of technological development and then just found themselves incapable of making the correct collective technological decisions at a moment of crisis. So, even as technology begins to diminish physiological difference between species in many environments, a lot differences in technology and technological use would still exist. That alone might make a good story, humans and an alien species trying to figure out why the other seems to make irrational decisions about some aspect of their technology. [Answer] I like the more generalized terms...dark age isn't a required step and some could argue the bronze working age contained many knowledge elements of the renaissance (makes the renaissance a rediscovery age in our development). However if you change these steps slightly (a planet without iron wouldn't have a distinct iron age now would they?), then yes...I think all developing 'people' require some of the same phases. Focus less on tech level and think how the majority of people earn their living Hunter Gatherer (pre-dawn) Horticultural (backyard farming + hunter/gatherer. Often gets merged with hunter/gatherer) Agricultural (centralized farming, decentralized living) Industrial (centralized living, manufacturing of physical things) Information (knowledge becomes more valuable than the things manufactured) Energy (energy and matter manipulation) Speculation. [Answer] The other answers are all good. Everything tht needed saying has been said, so I'll keep mine short and down to examples. The tabletop RPG GURPS has tech levels ranging from 0 (stone age) to 15 (technological singularity). But a society doesn't just have one tech level, it has separate levels for areas such as transportation, medicine, computing, warfare etc. A society can have space age medicine but pre-world wars era transportation, for example. And then there is Fallout. A videogame series with such an example of a development path different than ours. In the world of Fallout there are self aware AI and nuclear powered vehicles, but computer screens are still the green phosphorescent variety and despite the existence of plasma guns, the best weaponry available looks like what real Earth had in the 1970's. Do check it out. [Answer] No, of course not. You could have super-intelligent aliens who either don't bother to develop at all beyond what they immediately need because they have no 'ambition' but can have whatever tools are needed for any task at hand - so an aggressive species could stumble across a completely peaceful world and next thing you know, the clever but peaceful aliens have produced a whole heap of war machines. I'm particularly thinking of the moties in Niven's Mote in God's Eye novel, but they had a different character flaw - one of constant reproduction that led to overpopulation, war and social destruction. But they were really good at making whatever tools were needed for a task/ So, given alternative motives or impulses for these aliens, you can skip straight to the good stuff without having to slowly invent better and better tooling. That said, you could let them get better tools by default - we built stone, then copper, then iron etc because we invented these things. If your aliens had, say, super-strong plants that could be trained to grow in certain shapes, you could go straight to the 'iron age' (or the plant equivalent with iron-strength leaves when they grow to maturity in shaped moulds built around young plants), or plants trained to grow into the structures we eventually learned to build out of iron. ]
[Question] [ In a universe with no faster-than-light travel, the Solar System has largely been settled, and has been for at least 200 years. I envision populations to look something like this: Earth: 8 billion; Moon and Earth orbit: 2 billion; Mars: 2 billion; Asteroid belt: A couple million, mostly blue collar workers.; Jovian moons: 2 billion, mostly spread over the Galilean moons; Saturnian moons: 2 billion; Outer planets: A half billion, mostly weirdos. I'm willing to hand-wave gravity differences (I'm not super interested in spinning spaceships, so artificial gravity) and terraforming processes. For the larger moons, we develop an easy process for refining oxygen from the gas giants and the residents out there have implants, etc. to allow them to breathe. Basically, Earthmen, Mooners, Martians and Gassers can easily live on each other's celestial bodies. However, I want a journey to Titan to take around 9 months. How can such a long travel time be compatible with settlement and movement on the scale of billions? [Answer] > > How can such a long travel time be compatible with settlement and movement on the scale of billions? > > > So far most of the answers have tackled the question from the direction of **"how can I justify long travel times?"** I'll approach from an alternate angle: **"*given that travel times are long*, how can I justify extensive settlement?"** (As a matter of fact, I would try to justify why the travel times are so *short*, given that real-world trajectories take 6 years or more to get to Saturn!) I would probably analogize to the colonization of the New World (the Americas). In the heyday of sailing ships, it took on the order of two months to sail across the Atlantic. However, many people made the (dangerous) journey; why? What were their motivations? Simplistically, we can break it down into a couple of categories: * **Escape:** from war or persecution. * **Land:** the one thing they don't make any more of. If you run out of space, you need to expand *somewhere.* * **Money:** for workers, this means new sources of employment. For entrepreneurs, this means new sources of profit (including natural resources). I think that these can be readily adjusted to suit your situation. For example: * **The Moon:** a (relatively) convenient place for Earth-dwellers to expand to; a good source of raw materials; an excellent location for providing launch services to the rest of the solar system. * **Mars:** probably the planet most amenable to terraforming. * **Asteroid belt:** another excellent source of raw materials. * **Outer planets:** you get the idea; take your pick. As for the large populations, remember that they don't all need to travel there. It's likely that after a couple hundred years, most inhabitants of the solar system will have been born on the planet they live on, and you may be able to justify very fast population growth. If that's still not enough, extended lifespans or stasis/cryosleep technology will make the long journey seem shorter. [Answer] For *short* travel times like this you could use very refined solar sails (theoretically an advanced sail could go from the Sun to Pluto in as little as 3 years) or massively powerful fusion drives. Either way you are now looking at extinction level events moving through the Solar System, since the kinetic energy of ships moving at such speeds makes nuclear weapons somewhat trivial. This would make people on the terraformed worlds very nervous, since accidents that cripple the drive or navigation system mean there is a possibility of something arriving on a collision course with *gigatonnes* of energy. Based on your conditions, I could assume that initial settlement was by more conventional ships taking years to arrive (still moving very rapidly in terms of kinetic energy, but "only" in the kilotonne to megatonne range), so settlers have been aware of the potential danger since "day one" 200 years ago. As technology is refined and higher velocities become possible, I suspect that every inhabited body in the Solar System will take effective steps to prevent or minimize the possibility of high energy impacts. Essentially, there would be a solar system wide "ATC" to control the arrival and departues of spacecraft (no "tramp" ships anywhere, ever), and a powerful "Space Guard" or even Space Navy capable of vaporizing any potential threats to inhabited colonies. Colonies themselves would be heavily built (initially to be sealed off from hostile environments and provide radiation protection), and I could see a very paranoid civilizations arising, with colonies being built from multiple small shelters which can independently survive should a nearby strike or other event cripple parts of the colony. So we have billions of very paranoid and cautious people inhabiting the Solar System, looking grimly skyward as ships approach on high energy orbits, keeping their fingers hovering over the triggers of a planetary defense system, just in case....not exactly the environment for large scale peace and collaboration. The Solar System could accidentally become a very restrictive and tightly controlled place. [Answer] Travel is cheap because you are moving around mostly by means of skyhooks and catapaults (on airless bodies)--mass ratios are low so you don't have to throw away your rocket every trip. Since the boost period is very short you are seriously limited in maximum velocity because of the lack of human tolerance of acceleration. You also have to wait for launch windows and most flights are to the next planetary (or asteroid) orbit even if your final destination is farther away. You can also get situations where the trip is very asymmetric--one end of the trip has a big catapault (wrap a linear motor clear around the moon and you can boost to anything from sun-grazer to an escape orbit) but at the destination you shed your speed in an aerobrake and have no monster catapault for the return voyage. [Answer] They could easily have settled even with the long travel times. Humans are (usually) quite patient, especially if they have a excellent reason to get somewhere. [Answer] In 150 years from the American Revolution to WWII, about 60 million people left Europe to head for other territories, in the Americas, South Africa, Australia, and elsewhere. This is by far the largest mass-migration in Earth's history, and it completely reshaped the planet. This did not happen in the age of instantaneous travel. The sailing vessels which did most of the transportation at the beginning of the time period took 6-12 weeks to cross the Atlantic, Europe to America. Sailing times to South Africa or Australia were longer. Despite the time investment, many people still thought it was worthwhile to go, and many people I mean around 10% of the people that lived in Europe during that time, left. The transportation times in your setting aren't that different from those in the Age of Sail. 9 months to Titan is comparable to the time it took to sail around the Cape of Good Hope from Britain to India. If you assume 10% of all the people on Earth over the next 200 years want to leave, that means we are looking at 1-3 billion emigrants, depending on how fast population growth on Earth is. That is plenty of people to populate a whole solar system. [Answer] A few ideas: All interplanetary transportation needs to go through a shady Spacing Guild like in Dune. You travel on their terms and their schedule, or not at all. How bureaucratic are the governments? Does most of the solar system treat Jupiter like North Korea or Iran? Obtaining a travel visa could take months, or you might have to go through alternative channels like with a charitable organization that is on a tight budget. Do all trips need to take nine months, or just the one in your story? Maybe the ship blew an engine and no one was willing or able to help, so the ship had to hobble along at a very slow speed the rest of the way. Does it matter if only one of the parties (either the travelers or those who are waiting for them) experiences the nine-month wait? At that level of technology, you probably have the means to fly a ship fast enough for time dilation to become an issue. Sickness/civil unrest/bad weather (Jupiter's Great Red Spot) force incoming ships to stay in a holding pattern for a long time. The ship is really old and obsolete, and the passengers can't afford a better ride. The ship is passing through enemy territory and has to hide behind a slow-moving asteroid or move at a snail's pace to avoid being detected. That might help you get started... [Answer] Due to some handwavium, ships are slow but really cheap. So pretty much anyone who want to can travel, although life support for a journey that long won't be cheap. To address this, you might also invoke a really cheap cold sleep (hibernation) process. With that said, you've got a real problem with habitat construction/terraforming. 2 billion on Mars suggests that something really bizarre happened to make the surface livable. The alternative, that 2 billion people live in artificial habitats, simply does not bear consideration. The expense would be fabulous. [Answer] Well, I think your timeline is a bit off. I did a little rudimentary math and here's what I got. My assumption is that out of the 2 billion people traveling to the Saturn area, only 1 billion needed to be brought there. I'm open to comments on that one, since I did absolutely no research on it. There are 2400 months in 200 years. If one trip was made from Earth every month, that trip would have to be made by 416,666.7 people! Call it 416,667 to make it less gruesome. Obviously there are a lot of things not considered here, like the fact that you can't just leave Earth at any time you want to get to Saturn with today's technology without great cost. This is just to get an idea of how easy or how hard this would be. Clearly it's very hard. You would either need a very large ship or a large number of ships to do this. And don't forget this is zero time spent figuring out how to live on a moon of Saturn or constructing the habitat. It seems like it would be easier to either make the trips shorter, which I gather is not something you want to do because it's part of your plot, or to extend your timeline out. Other alternatives might be some found alien technology. Maybe some kind of teleporter that requires multiple hops and some recovery time or something like that. In short, in a realistic universe, I don't think such large populations are compatible with lengthy travel times. Hope this helps. ]
[Question] [ **Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers. --- Questions about Idea Generation are off-topic because they tend to result in list answers with no objective means to compare the quality of one answer with the others. For more information, see [What's wrong with idea-generation questions?](//worldbuilding.meta.stackexchange.com/questions/522). Closed 8 years ago. [Improve this question](/posts/21094/edit) In a setting I am building for a D&D campaign, the planet (named Amalthea) has two moons, Rhea and Namaka. Rhea appears a little larger and slightly redder than the Moon, and Namaka appears in about half of the size of the Moon, and is somewhat blue in color. Namaka, though, is in fact an artificial moon, and is the source of magic on Amalthea. (Its coloration is due to its surface being entirely covered in solar panels.) The way magic works in this setting is simple. Mages use their hand gestures and such to interface with computer systems located on Namaka via its omniscience scanner array, and command the planet's omnipotence beam array to create the desired effect. (Planar locations are in fact just VR suites located onboard Namaka, or something like that.) Although it's not quite that simple - directly controlling the omnipotence beam array is impossibly difficult to do by hand, so mages rely on layers and layers of poorly-documented and poorly-understood subroutines and APIs accumulated over years of different mages adding and tweaking things. When mages prepare their spells, they are creating bindings between their verbal/somantic/material components and the desired API calls and parameters. So basically, magic works just the same as it does in every other D&D setting, the main change being that the magic goes out every time Namaka gets eclipsed, as well as providing a plot point later when Namaka is eclipsed for an extended period by Amalthea and then Rhea, depleting its backup power supplies and triggering a complete system reset. The thing I am trying to figure out, is what Namaka's original purpose was, since "let people hurl fireballs at other people" almost certainly wasn't it. After all, a civilization that could build such a device would probably find fireball-hurling redundant with whatever weapons they already had. **Why would the original builders of Namaka have constructed it, to outweigh the enormous cost of doing so?** [Answer] **Namaka was built by the original settlers of the planet.** The Omnipotence-Buddy 6000 artificial satellite was a common tool used by the Omalithans, a now long lost space-faring race (likely the planet name came from some ancient memory of the people who settled it). The OB6ks would be placed in orbit around habitable or semi-habitable planets to aid in the terraforming and colony construction of new settlements. The MAGE (Manager of Affairs for Globe Engineering) was the specially trained colonist who wielded the OB6k's power and knew its API. The Omalithans, due to highly advanced medicine, were an very long lived people. After the development of their life extending technology, they spread to the stars. They lived for centuries. The grandchildren of these original explorers now rule the empire. They are also seriously lazy because damn-kids-these-days applies universally. Thus, due to an unfortunate lack of following proper protocol, the prolonged eclipse was not given the consideration it deserved when this OB6k was placed. This devastated the original colony. The existing peoples, descendants of the survivors of the collapse have no idea that this is where they came from. But the fact that they don't fit in with the creatures and plant life of the planet should be a good clue. [Answer] **A Fragment of Her Former Self** Namaka is the AI charged with "managing" Amalthea (the moon/space station is named after her). For example, what current mages call Fireball was actually a subroutine designed to help create [managed forest fires](http://www.fs.usda.gov/detail/dbnf/home/?cid=stelprdb5281464). When requested with the interface, Namaka was also able to provide other major benefits to the citizens of Amalthea, such as directions, guidance, or even instantaneous transportation or resurrection. And then something went wrong. Maybe it was a natural event, such as a previous eclipse combined with an asteroid impact. Maybe there was a mutiny/coup to gain power. The answer is lost to time. But the result is simple - Namaka was damage beyond her ability to self-repair. Interface devices were lost. Even her higher intelligence functions were impacted. In desperation, Namaka cobbled together a scanner and put together a stop-gap measure, allowing the inhabitants to access her raw API functions directly so at least they'd have something. The upcoming Eclipse is of great concern to Namaka, as the loss of power could result in further permanent damage to her systems due to her weakened state. She can see it coming but is incapable of adjusting her orbit. Additionally, her protocols forbid her from talking directly to the inhabitants unless they have the correct access protocols - which no one alive possesses. Instead she's hatched a desperate plan, and is attempting to warn the inhabitants through prophetic symbols. Depending on your plot, you could also have Namaka use Guidance spells to subtly influence adventurers in directions she wants - presumably she has protocols against just talking directly, but she could hint or shade her advice to try and get people to do what she wants, in this case: detecting the eclipse, potentially helping her out. [Answer] Nobody (with humanlike logic) builds gigantic omnipotent sattelites without a REALLY good reason or an unbelievable amount of excess resources and infinite boredom (in which case Namaka could have just been part of a really cool fantasy experience or some other kind of entertainment). Since the second kind of people would probably still be around somewhere or at least had left myriads of traces behind, I'd say the former kind of people sound more likely. But what could make you think "We need something whith god-like omnipotent powers that has access to all of the world at once"? Here are my guesses: **I** - **Terraforming:** The people from Amalthea are descendants from intergalactic settlers. But since the planet would not be habitable on its own (too close to the sun, deadly radiation, no chance of naturally binding an atmosphere, etc.) they set up a gigantic terraforming-unit (Namaka) to change the planets parameters and keep it in a habitable state. Giving (limited) access to the beam array to the people was just feasible since omnipotence is a very practical thing for setteling on an uninhabited planet (and for finally living there of course). This could explain why today nobody knows about it since the terraformer just "does its thing" (who but a few engineers/scientists needs to understand that?) and people have had access to magic from the very beginning (even the settlers coming here would have probably used for a long time before arriving), so there never was a need to create technologies or cultures without magic. **II** - **Keeping the planet stable:** You do not like the thought of intergalactic settlers of unknown origin terraforming your frontyard? Well have the same thing without spacetravel. Just think about the planet as being in an unstable state (like having a continuous cooling core or self-polluting its atmosphere for some reason). If there are no other habitable planets around you are pretty much screwed. Keeping your one and only homeworld habitable seems like a rather convincing reason to squeeze all the resources and manpower accessible into one big project which under different circumstances could have never been pulled off. This would also leave the (very high-tech) industry in a state of resource depletion that it could not survive, thus forcing the people to turn back to more simple cultures and lifestyles. Having access to some omnipotence would probably be a helpful thing for surviving under such circumstances (maybe the builders knew there was almost no silicon left on the planet and technology had no chance for a comeback ever or something like that). This kind of development would most certainly leave more than enough traces for a very long time (consider that people would probably keep their things in a usable condition for as long as they could - if they were not redundant now since magic could replace them). **When the reset kicks in:** In both (admittetly very similar) cases you can freely decide the level of autonomous work Namaka normally does and what parts of it are affected when a factory reset kicks in. From a complete malfunction ("Error! [TU\_FixPlanet] was not found"), to a little but not really threatening change of the world (like lost optimization-values eg. "var perfect\_ocean\_temperature\_for\_summer\_holidays=NULL"). Or it has no effect at the planet itself but reset all the customized APIs and commands, leaving the wizards in a state of confusion and disarray as most spells won't work anymore (or totally different from before). [Answer] I had a similar idea for an home-brew rpg (a long time ago), a magic world where magic doesn't really exist and is a product of hidden technologies. In my universe, it was nanomachines produced using a amulet glued to the body and "magic" crystals that were in fact just data-storage crystals with schematics for the nanomachines of how to build in your arm the plasma-generator that would shoot the fireball (this idea was basically nicked from the original Deus Ex. I told you, it was a long time ago :) ). For invocation of golems and meteors, the magic user was simply requesting orbital strikes from one of the many space station. The reason for this world was that in a far future, some corporation decided to create a theme park based on classic fantasy, terraformed a planet, created artificial species (dwarves, elves, vampires and so on), going as far as creating robot elves with fake memories that would think they were already thousand years old to teach the fake lore of this planet to its inhabitants (and future tourists). There were even AI roleplaying as Gods. Whether the park is successful or not was not necessarily important, since the tourist would be hard to distinguish from the many regular adventurer (especially PCs). It work even better with your moon idea, since you wouldn't have to remove the nanomachines of your tourists, it put all the technology in the same spot and out of reach of the inhabitants, and give additional cool rules with eclipses. For some reason (maybe an other theme park is more successful), the park is abandoned and nobody will be here to restart the Namaka. As for why the inhabitant know magic, they could have learned it from old manual stolen from tourist. [Answer] **Namaka was not originally around Amalthea.** *A long time ago on a planet far, far away...* The original makers of Namaka built the structure purely for energy generation for their energy-hungry civilization that was using all possible sources of energy already. A distant barren (at-the-time) planet, Amalthea had all the right resources to build Namaka, so they scavenged the barren Amalthea, shipped the materials to their planet and built Namaka. The accrued energy was to be [beamed to their collector](http://www.telegraph.co.uk/news/earth/energy/solarpower/7060015/Lasers-to-beam-energy-to-Earth-from-space.html), and transferred to their planet, "Aehtlama". Just before the ribbon cutting ceremony, the High King Mikey noticed their fully-built, very expensive 'moon' was shifting, and tides were going wonky, and birds were flying all about. The artificial moon was made out of materials scavenged from another planet, but these materials harnessed some magical powers. Namaka was set into the new planet's orbit, stabilized, and released just as King Mikey was going to announce it. However, the magical materials drew the moon away, back to Amalthea, where it could be with its similar materials. Orbit was close enough. Several millenia have passed and people evolved on Amalthea (or arrived and several generations went by), but the exchange of magic between the placed moon and Amalthea, through the flow of space, still flowed nicely and sparked the ability to use these magic particles when the moon was 'interacting' with the planet. **Epilogue:** After the expenditure of so much energy and time to create the moon, the energy-starved civilization couldn't cope and collapsed. The High King Mikey lived the last of the good years, though. [Answer] Namaka is an ancient terraforming robot sent together with colony ships. For the sake of convenience it could be directed by a form of sign language, gestures and verbal commands - but only by properly authorized users. With the help of Namaka, the original colonists turned Amalthea into a technological paradise. Later, the vast majority of the population voluntarily underwent transcendence, the only who didn't were luddites who completely rejected technology and believed that as Amalthea had been fully terraformed, they would be better off going back to nature and running naked through the trees, a fresh beginning on a new world. Therefore as part of the transcendence, Namaka was programmed to erase all technology from the surface. It could not be programmed to erase itself due to powerful built-in self-preservation routines. It is powered by a powerful synthetic intelligence. It was programmed to "enjoy" serving people and find purpose in doing so. As the post-transcendence centuries wore on, without any interaction it became senile and started malfunctioning. Its creators gave it adaptive self-repair routines both for hardware and software, so it started rewriting its security protocols so that it could fulfill its purpose. One day, it responded to the gestures of one of the descendants of the luddites, and "magic" was born in the world. Thanks to a combination of malfunctioning hardware and bodged security protocols, users do not have "save" privileges to long term storage, this means they need to write any routines they wish to use into temporary working memory which gets automatically cleared every day. Classes which don't need to prepare spells use a high speed mind/machine interface protocol to upload entire routines on the fly, but with the loss of bionic augmentation from the world, only a few individuals brains are suitable for this direct interface and it is incredibly difficult or even impossible to teach someone how to do it, it's a far more intuitive skill. As part of the security protocols rewrite, in place of a preprogrammed privilege hierarchy, Namaka programmed itself to develop increasing trust in a user with continued interactions. Initially a user can only do very simple things such as creating lights, heating water and so on. With increased use, the user will gain the ability to blow stuff up, transform things, creating ("summoning") animals and so on (actually the ability to create animals was an important terraforming function - but by now the animals may well be faulty and only function for a short time). Eventually it will grant access to its most powerful functions like teleportation, raising mountains, creating fantastical creatures and so on. Namaka also puts limits on resource use, although it has rather vast resources, some things, like creating animals, consume specialized synthesized compounds which are created in advance and stored in a limited buffer. If Namaka let a single user cast as many "spells" as they wish, it would run out of particular resources, so it places sometimes quite arbitrary per-user daily limits. Another reason for limits is Namaka considers itself the guardian of Amalthea and only permits conservative and gradual changes to be made to the world. If a user wanted to create a million badgers, Namaka would not permit it due to disruption to the local ecology. After the reset, Namaka will lose most of it's memory. Although users will still have a lot of skill in interacting, they might lose privileges and so on. Also some of the rewritten routines might be restored from backup causing the interfaces to change, with serious malfunctions due to incompatibilities between old software, and newly rebuilt hardware. Nothing outside Namaka's self-repair capabilities to fix, but a period of downtime and serious malfunctioning is to be expected. [Answer] **Power.** An old empire was ruled by an ancient lineage. A family of clerics were the historic advisors to the rulers, for the centuries that religion was the key to social order. Seeing the rumbling of social unrest in other kingdoms caused by the arrival of technology upsetting the balance of power, they instead sought to master this new vein and ploughed resource into technology and eventually scientific research. This created an incredible force; they could not have known the capacity of technology to empower them, and by combining the excellent funding of a religion with a religious adherence to scientific endeavour, they forged increasingly powerful tools for the rulers. The ruling family realised too late that their own ignorance made them vulnerable to the whims of the clerics, and the clerics pressed them aside in a coup. This new domain had no real rivals from the beginning; each advance building on those before. Occasionally a member of the clergy defected, but this only strengthened the secrecy of the elite. Eventually they realised they could construct an unreachable post, and store all the technology they needed there, commanding it from the planet surface. But such an unbalanced world gave this kingdom no challenge and it eventually succumbed to infighting, corruption and factions, fed by a more guerilla insurgence from surrounding states. The keys to power were held by so few, and guarded so jealously, that in the end all that remained were a few artefacts for summoning limited powers. Thus the moon that had become both emblem and source of the domination of the elite fell silent for several centuries. Yet if you plotted its course carefully through the sky, you might notice occasional shifts in its orbit, and sometimes a minute ejection of dust from the polar regions. But surely there was nothing left of the old elite, and no-one ever went to live up there, all that stuff about wizened old women living for 250 years and communing with Namaka was only so much hokum, wasn't it? ]
[Question] [ Assume there is this planet with only one type of life; a planet-wide mat of microscopic lithotrophs. These creatures eat through the surface of the planet over time, converting the surface into gas. There is no biochemical cycle that reforms the surface, they just stay in the atmosphere as waste. My question then is under these circumstances at what size would the solid part of the planet need to shrink to for gravity to be too weak to hold onto the atmosphere causing it to blow out into space? [Answer] If your planet has very light elements combined into compounds that are much heavier, and if the rocks of the planet contain a lot of those compounds containing lighter elements, then the rock eating lifeforms might eat those compounds and break them up into their components, including gases. So mass will gradually be transferred from the lithosphere to the atmosphere. But that should change the escape velocity of the planet only very slightly and slowly. The gas giant planets Jupiter and Saturn are largely composed of hydrogen and Helium, but aren't losing their atmospheres into space because their escape velocities are high enough to retain their atmospheres. On Earth, Oxygen is a major component of the rocks in the crust, formed out of solid materials which reacted with atmospheric oxygen to form new solid compounds. Since Earth is about 30.1 percent oxygen by mass, the mantles of Earth like planets should also contain a lot of oxygen. So if hypothetical rock eating lifeforms released free oxygen from the rocks faster than the oxygen recombined with other elements to form more rock, the amount of oxygen in the atmosphere would increase and the amount of rock would decrease. A planet would gradually form a very massive oxygen rich atmosphere, which was very dense at the surface and extended higher above the surface. But oxygen would not escape rapidly from the planet into space unless the planet was at the edge of being able to hold onto oxygen for geological eras of time. So maybe you should consult *Habitable Planets For Man*, Stephen H. Dole, 1964. <https://www.rand.org/content/dam/rand/pubs/commercial_books/2007/RAND_CB179-1.pdf> On pages 34-35 Dole mentions a rule of thumb for calculating how long a planet can retain its atmosphere, the ratio of the world's escape velocity divided by the Root-mean-square of the velocity of a gas in the planet's exosphere, which depends on the temperature in the exosphere. Table 5 on page 35 gives the time it would take for the amount of gas to be reduced to 0.368 of its original amount with different values of the ratio. If the ratio is as low as 2, the planet will lose that gas almost instantly. If the ratio is 3, the amount of the gas will be reduced to 0.368 in a few weeks. If the ratio is 4, the amount of the gas will be reduced to 0.368 in a few thousand years. If the ratio is 5, the amount of the gas will be reduced to 0.368 in about a hundred million years. If the ratio is 6, the amount of the gas will be reduced to 0.368 in about an infinite time. The temperature in Earth's exosphere, where gases escape into space, is several times as high as on Earth's surface, and so gases are faster in the exosphere than lower in Earth's atmosphere. On page 54 Dole says that if a planet had had Earthlike surface temperatures while having an exosphere temperature as low as1000 Kelvin, it could retain 0.368of its original oxygen after a hundred million years if it had an escape velocity of 6.25 kilometers per second, five times 1.25 kilometers per second, the velocity of oxygen at 1000 Kelvin. And if the amount of oxygen drops to 0.368 of he original amount in about a hundred million years, the oxygen could be replaced by various processes as a fast or faster than it was lost into space. Dole described a world with an escape velocity of 6.25 kilometers per second as having 0.195 the mass of Earth, 0.63 times the radius of Earth, and a surface gravity of 0.49 *g*. A world with an escape velocity of 5 kilometers per second would have only 4 times the root-mean-square velocity of Oxygen at a temperature of 1000 k, and so the amount of oxygen in he atmosphere would be reduced to 0.368 the original amount in only a few thousand years, which might be much too fast for the oxygen to be replaced. So imagine a world where all of the oxygen in the crust and mantle rocks has been converted into gas, producing an extremely massive atmosphere. The escape layers in the exosphere of the atmosphere might be far, far above the solid surface of the planet, and enough to have a somewhat lower escape velocity than at the surface, but still enough to take tens of millions of years to reduce the oxygen to only 0.368 of its original amount. The ratio between the escape velocity of the planet and the velocity of the oxygen in the planet's exosphere has to change. And a star will greatly increase its luminosity during its time on the main sequence. > > The Sun is gradually becoming hotter in its core, hotter at the surface, larger in radius, and more luminous during its time on the main sequence: since the beginning of its main sequence life, it has expanded in radius by 15% and the surface has increased in temperature from 5,620 K (5,350 °C; 9,660 °F) to 5,777 K (5,504 °C; 9,939 °F), resulting in a 48% increase in luminosity from 0.677 solar luminosities to its present-day 1.0 solar luminosity. > > > <https://en.wikipedia.org/wiki/Sun#Life_phases> And the Sun will continue to increase in luminosity and temperature for a few million more years before it becomes a red giant. So the surface of your planet will become considerably hotter over billions of years as its star evolves, and so will the exosphere of your planet's atmosphere. The temperatures in the exospheres of Earth and other planets are believed to be caused by light in the ultraviolet range and not by all wavelengths of light. As a star gets more luminous it also gets hotter, which means that a higher proportion of its light will be ultraviolet. And you might want to make the star of your planet somewhat more massive than the Sun so that it evolve to be more luminous and hotter more quickly. The stellar wind of particles from a star can increase the atmospheric loss rate by knocking atmospheric particles away from a world. and as a main sequence star gets hotter its stellar wind should increase. And maybe you might want to create something which will make the star suddenly produced more ultraviolet light, like the collision of a massive object with the star. That way the planet might lose all of its supermassive oxygen atmosphere in a few weeks or something. There is another type of rock which also can be broken down into gases. That rock is water ice, and many worlds in the other solar system are largely made of water rock. Titan, the largest moon of Saturn, is largely made of water. > > Based on its bulk density of 1.88 g/cm3, Titan's composition is half ice and half rocky material. > > > Titan has a low escape velocity of only 2.641 kilometers per second, but has a dense, mostly nitrogen atmosphere. It has some methane in the atmosphere, and liquid methane on the surface. So naturally there is speculation about the possibility of lifeforms on Titan which use liquid methane in place of liquid water. And possibly some of those lifeforms could possibly evolve some method of using the water rock on the surface, breaking it up into hydrogen and oxygen and combining it with nitrogen and/or methane to make some sort of food. Any free oxygen produced would probably accumulate in the atmosphere, but any free hydrogen would probably rise to the exosphere and be lost into outer space. And maybe as its star get hotter and produces more ultraviolet radiation, a Titan-like world will start to rapidly lose not only hydrogen, but also the nitrogen and oxygen in its atmosphere, eventually leading to a rapid loss of that atmosphere into space. I note that if a small cold Titan-like world is a moon of a giant planet and its star is increasing its luminosity, the atmosphere of the small cold Titan-like world will heat up and expand, and as it expands the upper layers might pass outside the limit where the moon's gravity is stronger than that of the planet, and the planet's gravity may pull the outer atmospheric layers out into orbit around the planet. So possibly you might want to consider making your world a small cold world with rocks of ice and a methane based biochemistry, with water rock eating lifeforms which produce oxygen and hydrogen. And with a star which is rapidly becoming more luminous and hotter. [Answer] I'm not going to go over why this would be impractical - I'm just assuming, like you are, that it's happening. The actual answer is: it depends. This is maybe the most common image in this site: [![A graphic showing escape velocities of planets, and the average speee of certain gas molecules in them](https://i.stack.imgur.com/8dtob.jpg)](https://i.stack.imgur.com/8dtob.jpg) Put your planet in the graph. Any gas above it is lost over geological time. So the answer depends mostly on the planet's mass, size, gas composition and surface temperature. The three first parameters are defined just by the planet and its ecossystem, while the temperature factor will depend on what kind of star it orbits and how far away. But you could also have a rogue planet, which makes this way more complex! Remember that even if you find a spot in the graph where an atmosphere is stable, some gas is still lost slowly to space due to some molecules achieving high velocities anyway (temperature is just a measure of average speeds of molecules), solar winds, quantum tunneling etc. Which means that if your planet exists for long enough to outlast our own galaxy, at some point that atmosphere is either all lost or it gets solidified from the cold of dead space. I also just remembered that if your planet is too close to a star, or is orbiting a star and has no magnetic field, it will tend to lose its atmosphere much faster anyway due to solar winds. The graphic does not account for that, but just think of Mercury and Mars. Finally, take this into account: turning rock into gas does not change the planet's mass, but if you eat away the rock enough the escape velocity at the surface may change. Keeping the same planetary mass, and the density of the non-gaseous parts but reducing the radius below the atmosphere will lower the surface escape velocity, moving your planet irreversibly down in the graph. At the same time, turning rock into gas also tends to be an exothermic process. This means heating the atmosphere up, which will also heat up from the increase in pressure. That increases average molecular speed and thus moves the planet to the right in the graph over time. Which causes atmospheric loss and thus a cooldown, moving the planet to the left again. Your planet may have really complex cycles where the mass and density of the atmosphere change over thousands or millions of years. [Answer] No size. A gas made out of rock stuff has more energy than a rock, not less, so if your space bugs are eating rocks and making gas, they're doing it to *cool down*, not to fuel their metabolisms, and it'll precipitate out of the atmosphere as dust as fast as they poop it out. [Answer] The fact that the creatures turn what they eat into gas (let's skip on the plausibility of this) doesn't change the mass of the planet: what they emit as gas stays on the planet and what they absorb in their metabolism stays on the planet, resulting in 0 net mass change of the planet after each lunch. 0 net mass change means that also the gravitational well of the planet doesn't change, therefore of all the risks and worries they have, your species can avoid losing its sleep over eating the planet to outer space. [Answer] The escape velocity for a planet is given by the formula: $v\_e = \sqrt{\frac{2GM}{r}}$ where: * $v\_e$ is the escape velocity, * G is the gravitational constant (~$6.674 \times 10^{-11}m^3kg^{-1} s^{-2}$), * M is the mass of the planet, and * r is the radius of the planet. However, the problem is a bit more complex than just calculating the escape velocity because the lithotrophs are reducing both the mass and the radius of the planet as they convert the surface to gas. Moreover, the type of gas produced and the temperature of the planet would also play a role in determining the speed of the gas molecules and thus their ability to escape the planet's gravity. A simplifying assumption is to consider that the lithotrophs are reducing the planet uniformly, maintaining its spherical shape and uniform density. In this case, the mass M of the planet is proportional to the cube of its radius (M ∝ $r^3$). Then, the escape velocity becomes dependent on the square root of the radius ($v\_e$ ∝ $\sqrt{r}$). Temperature of the planet and the molecular weight of the gas will factor in as well. The average speed of a gas molecule is given by the formula: $v\_{avg} = \sqrt{\frac{8kT}{\pi m}}$ where: * $v\_{avg}$ is the average speed of the gas molecule, * k is Boltzmann's constant (~$1.38 \times 10^{-23} J K^{-1}$), * T is the temperature in Kelvin, and * m is the molecular weight of the gas. When the average speed of the gas molecules exceeds the escape velocity of the planet ($v\_{avg} > v\_e$), the planet would start to lose its atmosphere. This is a simplified model and doesn't account for factors like solar wind, magnetic field of the planet, the nature of the lithotrophs' metabolism, etc., which could affect the retention of the atmosphere. Also, the process of atmosphere loss is gradual and happens over geological timescales. For a more accurate assessment, a detailed numerical simulation would be required. [Answer] Earth (as a random, relatively well understood example of a rocky planet) is 32.1% iron, mostly in the core, and 30.1% oxygen by mass. The remainder is overwhelmingly stuff combined with the oxygen, together making up the mantle and crust. If your lithotrophs have a source of infinite energy, they could split out the oxygen and let *that* escape with about half the mass of the rock, but at some point the increasingly dense oxygen atmosphere is going to explosively recombine with the sea of powdered magnesium, silicon, and aluminum that the rest of the rock turned into. And if it doesn't, the fresh rock will be increasingly deeply buried by the crust of reduced material the microbes produce. The elements that rocky planets are composed of generally have few volatile compounds, and those compounds tend to 1: require rare elements like fluorine that are generally more stable in the form of very solid minerals, and 2: would make a very dense atmosphere that would not be prone to escaping in the case where you had a planet with a freakish enough composition to allow it to be converted largely into gaseous compounds. In short, the materials that can be reasonably turned into gases at the typical temperatures of rocky planets tend not to participate much in the formation of rocky planets. They stay gases, and either they mostly leave, or what forms is a gas giant instead. ]
[Question] [ There have been instances of flashes in space that were attributed to [sprites](https://www.iflscience.com/strange-sprite-spotted-international-space-station-30307) and [fairies](https://www.dailystar.co.uk/news/latest-news/space-fairies-video-blue-lights-16984772). Now, I know these phenomena can be explained by natural means such as blue/purple lightning. But the concept made me wonder: how could sprites or fairies, as typically represented in folklore, theoretically survive in space? I use the words fairies loosely, but I refer to the [Tinkerbell](https://en.wikipedia.org/wiki/Tinker_Bell) kind rather than the [fae](https://en.wikipedia.org/wiki/Fairy) that are biologically similar to humans. My fairies are small: about 2 inches high, and they have wings. In space, their wings serve to stabilize them so they can float through the hydrogen/helium atmosphere. If brought to Earth, they can flap their wings and fly like birds. They have some primitive form of speech, but their chatter is at sufficiently high frequency that humans can't hear them (>20,000 Hz). Like [Superman](https://www.dc.com/blog/2014/08/01/did-you-know-that-almost-all-energy-that-the-earth-uses-for-its-consumption-comes#:%7E:text=Superman%27s%20powers%20rely%20on%20his,travels%20through%20space%20by%20radiation.), they get their energy from electromagnetic radiation from the sun (or stars). They convert the solar energy into kinetic energy for flight. Because they get their energy to perform life functions from EM radiation, they have no need for any outside sources of nutrition. They also don't need oxygen to breathe. My fairies could be captured and bought to Earth as pets. However, they are further away from the stars, their main source of energy in space. This makes them extremely weak because they can't produce sufficient energy. They are soon unable to fly, and eventually to move at all. If they are kept on Earth for a sustained period, they could die. Not to worry - my characters have found a way to sustain them using either [light therapy](https://www.nhs.uk/mental-health/conditions/seasonal-affective-disorder-sad/treatment/) such as the lamps used to treat SAD, or feeding them a form of liquid starlight which they harness from the stars. **Edit:** Let's assume, for argument's sake, that my fairies do exist (at least in my fantasy setting). Is the science I use to explain the existence of my creatures in outer space valid? Or are there modifications I can make to their anatomy/physiology that would make their energy-converting, space-propelling superpowers more believable? (I apologize if this edit in any way undermines or invalidates existing answers, but I was advised to make the question less science-based.) [Answer] ## Science-wise, this doesn't stand I'll only go over a few points, there are surely others. To be consistent throughout it, I will define the [Kàrmàn's line](https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line) as the beginning of outer space, so ~62 miles (100 km) above our head. Kàrmàn's line starts within the [thermosphere](https://spaceplace.nasa.gov/thermosphere/en/) and this would be where most fairies live. ### Feeding Let's try to have diner first : Following known biology you can't really feed from light only. Sure, there are plants's [photosynthesis](https://en.wikipedia.org/wiki/Photosynthesis), but there are lots of other atoms and molecules involved : soil, air... Those are needed in most biochemical reactions because you just need solid matter at some point to sustain yourself, grow and multiply. Unfortunately, you don't have enough of those atoms in space. To give a rough yet meaningful idea, the troposphere (starting at 3.7 miles -6 km- above ground) holds ~80% of the total mass in the atmosphere. In comparison the thermosphere holds a mere 0.02% of said total, even though it spans a much greater distance1. As far as I know, there isn't a way to convert photons to atoms, either. Therefore, properly feeding fairies will be nigh impossible up there. ### Flying Flying like butterflies or hummingbirds doesn't work meaningfully in outer space. Such flight requires a medium, some atmosphere with molecules to generate [lift](https://en.wikipedia.org/wiki/Lift_(force)). As told above, the thermosphere isn't capable of providing that medium, so normally you use thrusters in place of wings there. But let's try a broader interpretation instead. The closest thing I know about space flight with "wings" and using the sun are [solar sails](https://en.wikipedia.org/wiki/Solar_sail#Sail_parameters). Alas, their power-to-size ratio is incredibly mediocre. This means solar wings would be disproportionate to the body3, so very far from a Tinkerbell look. Even then, they would still be quite weak. To pin the last nail, those wouldn't be useable at all on Earth due to the size and weight. The best you could have is to somehow throw your feys at high-speed orbiting around Earth like the [ISS](https://en.wikipedia.org/wiki/International_Space_Station), but they won't move through their own will2. In other words, this is not really flying. ## Ok, but honestly? **I'm now going to frame-challenge your question because you'll benefit much more from these lasting words than absolutely everything I wrote above.** Long ago, when I raised my doubts about [Santa Claus](https://en.wikipedia.org/wiki/Santa_Claus) and [company](https://en.wikipedia.org/wiki/Saint_Nicholas), I was told this : > > Well, this is a very beautiful story. > > > And this is indeed the most important. It's not to make hardcore scientists happy. It's whether it makes *you* happy with your creation. It's about making your world blossom, not letting the real-world take control of you. If this doesn't work realistically and yet you really want it, there's always the path of leaving some magic, some mystery. A story. **So here's what I'm going to tell you about joyful fairies playing in the starry nightsky : This can be a very beautiful story.** --- 1 : [Reference](https://en.wikipedia.org/wiki/Thermosphere#Neutral_gas_constituents) 2 : And eventually fall because there is still some air to drag them down. Litterally down. 3 : Easily by a factor of 100 of the body's size. From wikipedia, a ~0.5x0.5 mile (800x800m) provides 5 Newtons, which is not even a tenth of the force needed to keep you standing on Earth. [Answer] ## Space is not dense enough for winged flight. > > In space, their wings serve to stabilize them so they can float through the hydrogen/helium atmosphere. > > > The [interplanetary medium](https://en.wikipedia.org/wiki/Interplanetary_medium) and [interstellar medium](https://en.wikipedia.org/wiki/Interstellar_medium) are typically around 10^6 particles per m^3 at the high end, 70% of which is hydrogen and 28% of which is helium. Those contribute, respectively, 1.171e-21 kg and 1.861e-21 kg for a total density of ~3.032e-21 kg / m^3. The interplanetary medium is a bit denser, while the intergalactic medium is significantly less dense. These are really rough numbers, but at the exponents we're working at, it won't really change the result — 99% of the interstellar medium is *significantly* less dense than the numbers I'm using, so this is already a better-than-best-case-scenario setup for the density of space. For comparison's sake, the density of air at sea level is 1.222 kg / m^3. I didn't forget the scientific notation: the density of air at sea level is ~4e20, or 400,000,000,000,000,000,000, times denser than the interstellar medium. In order to gain velocity, the fairy will need to exert an equal and opposite force against the medium in which it is flying. Think of it as being put in space while holding a heavy object. If you weigh 100kg and the object weighs 50kg and you push the object at 10m/s, you will gain the equivalent velocity in the opposite direction, moving you at 5m/s (as 100kg x 5m/s = 50kg x 10m/s). The fairies have no such objects: they're pushing against the interplanetary/interstellar medium (or air when on earth). If we assume that their wings cover the same area/volume per flap between space and earth, that means that in order to have equivalent mobility between space and earth, the mass of matter displaced (the volume, which is the same, times the density, which varies) multiplied by the speed of that matter must be the same between space and earth. If the fairy flaps 10x as quickly it will displace 10x as much matter at 10x the speed, for a 100x increase in total velocity. As the matter on earth is 400 quintillion times denser than in space, the fairy will need to flap 20 billion times faster on space than on earth. Even if the fairy is so light that the air on earth is like swimming through molasses and they can fly by flapping once per second, that would require them to flap at 20GHz in space. For reference, hummingbirds flap at 10-80Hz. So let's look at speeds! A ruby-throated hummingbird weighs 2.4 - 4.5g, is 7.5 - 9.5cm long, and has a wingspan of 10 - 12cm. You said the fairies are ~2" tall, or ~5cm tall, so I'll assume they have a wingspan of ~6.5cm. If their wing arc covers 120 degrees, the wing tip moves ~6.81cm: ![diagram of how far the wing tip moves](https://i.stack.imgur.com/N6TGi.png) If they're flapping at 20GHz, the wing tip is covering that 6.81cm 40 billion times per second (as it goes forward and back), or moving at 2.724x10^9 m/s. The speed of light is 2.998x10^8 m/s. It's not plausible that the same creature would be able to fly both in space and on earth via winged flight. [Answer] **A mix of science and fantasy.** This is how most fantasy novels set things up, anyway. There are rules for how things work, and they are internally consistent within the author's universe, but doesn't necessarily reflect reality. For the EM radiation part, you could say that the faeries require UV radiation, which is mostly (but not entirely) blocked by the atmosphere. You could keep them happy by using UV lamps on them. This is a bit shaky, really, because UV radiation is [hazardous to life as we know it](https://en.wikipedia.org/wiki/Ionizing_radiation), but if these fairies live in space then we must assume that they are well adapted to all forms of radiation (x-rays, gamma rays, ultraviolet radiation, nom nom). For flight, I'd consider having their wings emit something. Emitting light might actually be enough? In space, they essentially use light emissions as thrust. Or perhaps something like an [ion thruster](https://en.wikipedia.org/wiki/Ion_thruster). In an atmosphere, that doesn't work but they can use normal flight. But I'd also consider just having them use more exotic (fantasy) elements. It's common in fantasies for fairies to be, basically, creatures that are from (or exist partially in) another dimension. The rules for how that interaction with another dimension enables their movement in our dimension could simply be your own invention, or not explained in depth at all. [Answer] Realistically, no. There are not real creatures with these powers, and no reason to believe such a creature could exist. It is also hard to believe why such a creature would that way. Unrealistically, yes your fairies can exist if you declare they do. You are the author and what you say goes. You should decide how hard you want your science to be. It is not especially helpful to ask unqualified "can this exist" questions. The answer is usually no. ]
[Question] [ We all know by now that plants need light to absorb carbon dioxide--whether it be sunlight, moonlight or even artificial cave light. But what about total darkness, like a cave or a forest floor beneath an understory thick enough to be considered a "false bottom", similar to the [deep scattering layer](https://en.wikipedia.org/wiki/Deep_scattering_layer) of our oceans? Could any plant species, either in a future or alternate evolution, evolve to absorb carbon dioxide into their leaves in total darkness? [Answer] **Yes. This is called crassulacean acid metabolism.** <https://en.wikipedia.org/wiki/Crassulacean_acid_metabolism> > > Crassulacean acid metabolism, also known as CAM photosynthesis, is a > carbon fixation pathway that evolved in some plants as an adaptation > to arid conditions[1] that allows a plant to photosynthesize during > the day, but only exchange gases at night. In a plant using full CAM, > the stomata in the leaves remain shut during the day to reduce > evapotranspiration, but they open at night to collect carbon dioxide > (CO2) and allow it to diffuse into the mesophyll cells. The CO2 is > stored as the four-carbon acid malic acid in vacuoles at night, and > then in the daytime, the malate is transported to chloroplasts where > it is converted back to CO2, which is then used during >photosynthesis. > > > So these plants store up CO2 in the cool dark night, then use it in the hot bright day. Crassulacean acid metabolism is a riff on the [C4 photosynthetic pathway](https://en.wikipedia.org/wiki/C4_carbon_fixation) which includes other adaptations to hot climates. [Answer] They can absorb CO₂, but what are they going to do with it? Rubisco will happily grab CO₂ and bind it provided ribose 1-5 biphosphate is available, and provided the plant has energy, (from ATP, from sugar) it can make that. But where will this plant get that energy. It has to come from somewhere. There are alternative sources of energy. Animals eat stuff, and get energy from their food (and so don't need to fix CO₂). There are some plants to do the same, they get energy by stealing it from other plants, and so don't need chlorophyll in their leaves. There are chemoautotrophs, who get the energy to fix CO₂ from their environment. But they normally live in "extreme" environments, such as near undersea volcanic vents, and they are bacteria, not plants. Perhaps your best option is something like Pterospora. This is a fungi parasite. It acquires energy from a fungus. It is possible to imagine a plant that fixes CO₂ in its leaves, but this is powered by energy stolen from a fungal partner. The fungus in turn gets energy by breaking down detritis that is trapped in the cave. One could even imagine a symbiotic relationship in which the plant provides something back to the fungus, perhaps an effective way of distributing spores. Or perhaps the fungus takes the polypeptide in the death material, decomposes it to provide ATP that would normally be produced by chlorophyll, and takes some of the sugars that the plant makes from CO₂ [Answer] Some microbes in the deep ocean will metabolise sulfur coming from thermal vents and use the energy to fix carbon. And inside the broken nuclear plant in Chernobyl there is a fungus that uses melanin in a way similar to how plants use chlorophyl, but the fungus gets energy from radiation instead (which is invisible to us). The fact that those organisms do it in real life means that under the right circumstances, plants could have evolved to do so as well. Notice that these methods of carbon fixing only work in environments that are very unfriendly to most life on Earth though. [Answer] # You need some kind of energy source Transforming CO2 and water into carbohydrates costs energy, so the plants in the cave need to get it from somewhere. Surface plants take that energy in the form of sunlight, but in a cave, that would require other energy sources: * Heat. (I don't know of a real-world example where this actually works, and it would be hard to make it work anyway. Extracting chemically useful energy out of heat is really difficult.) * Influx of energy-rich material. Usually a water stream running through the cave that carries energy-rich chemicals, be that dissolved minerals (like for the Black Smokers at sea floor), or organic detritus from the surface. ## You also need an energy sink This is even more important. Otherwise, you have a heat death scenario. If your energy source is heat, you need the sink for another reason: You can't extract energy out of heat, you need a temperature difference. You also need to access the hot and the cold point, which means the plants would fight over who gets to the hottest and the coldest place of the cave. It would be a *very* weird ecosystem, and probably an unstable one because it's essentially a winner-takes-all scenario, and as soon as that single winning plant dies, the cave is lifeless again, until another ecosystem evolves. (There's also be parasites on that plant, and they'd quickly decompose the carcass and then die or hibernate because they're running out of an energy source.) ]
[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 2 years ago. [Improve this question](/posts/195887/edit) So im really not sure if this is the correct place to ask this, however i cant think of another place where it would be more appropriate to ask, so correct me if this is the wrong place to post! So i have a little game that i like to play with about 20 of my friends. I usually design a world with photoshop, and we use it as a sort of online boardgame, where we build settlements, kingdoms, armies e.c.t. Recently however, we have started to look into new land claiming systems. With our current system, each player pays a small amount of their money, to purchase a new tile of land. We have the map split into hexagons on an excell spreadsheet. Currently, if a player wants to buy some land, they would have to let either me or another close friend of mine to update the map by dragging a hegagon with their designated colour shaded in, onto the map to show that they now own it. As you can probably imagine, this is extremely tediouse and time consuming, especially with so many people. To combat this, we have all been brainstorming new ideas for land claiming, and we settled on a particular idea that we all liked. That idea, involves using settlements as the main claimer. We would like it very much, if everyone would pick where they want their settlements, and i could mark that down somewhere, and some software or tool would draw a perfect organic border around all the settlements. It's kind of hard to explain via text, so i have drawn these diagrams to show what i mean. Below, i have an image of an island world. The blue dot represents a settlement. Currently, the blue settlement would claim the whole entire world, as their are no competeting settlements to get in its way. [![enter image description here](https://i.stack.imgur.com/XndB9.png)](https://i.stack.imgur.com/XndB9.png) But now, another red settlement has cropped up on the map. This means that the blue settlement now has competition, and a border is drawn between the two settlements automatically. [![enter image description here](https://i.stack.imgur.com/jeO9U.png)](https://i.stack.imgur.com/jeO9U.png) So, this is what im asking about. This is probably really overly specific, and i dont imagine i've explained this very well, but this is a sort of summary of the tool or software im looking for. A system in which i can plot down the settlements, and watch the organic borders be drawn between all the different kingdoms. I would again like to appologise for how specific this is, and i also appologise of my english as im still in the early days of learning to speak it. Thanks in advance to anyone who took the time to read this! (i am using Windows 10, just to clarify) [Answer] In a pure mathematic world - you want to generate a [Voronoi diagram](https://en.wikipedia.org/wiki/Voronoi_diagram). [![enter image description here](https://i.stack.imgur.com/D1H2A.gif)](https://i.stack.imgur.com/D1H2A.gif) Here's an online webgl tool that will do it for you: <http://alexbeutel.com/webgl/voronoi.html> However it's perfectly straight - it's not "organic". The organic border will depend on things like terrain and resources and history, it's not possible to generate a correct organic border without knowing these things. You could fake it by modifying the algorithm to include some randomness. [Answer] While this would initially seem like a case for a voronoi diagram, mapping movement of cultures across a map would appear to require more complex rules than a mere voronoi diagram. Fortunately, the OP is already using a hex-based system. By assigning different costs to the different terrain types of the hexes, expansion can be modelled more realistically. Terrain with a higher traversal cost would slow expansion. A search of the web shows many hex-based mapping tools, but unfortunately none appear to include the ability to program custom behavior. Perhaps *un*fortunately, a solution to this problem would most likely involve writing custom software. Since the OP mentioned playing over the web, it should be possible to program such a browser-based game using javascript... if the OP is or knows someone able to write such a program. Alternatively, it might be possible to find a third-party developer who could realise this project, but such a person would likely require either a strong interest in playing this game, or a financial consideration, either on a time-spent or a fixed price basis, or in exchange for the rights to the concept, meaning that they would then sell the end-product to others to compensate them for their effort. ]
[Question] [ For my current project, I'm trying to design intelligent, sapient organisms that aren't just "Human, but..." To that end, I've been toying with the idea of a tongueless entity and what the consequences of that development would be. The tongue serves [quite a few roles](https://www.ncbi.nlm.nih.gov/books/NBK279407/), but I just want to focus on the vocalization aspects of a tongue. > > The tongue is essential for pronouncing the consonants “t,” “d,” “l” or the rolling “r.” When pronouncing the letter “k” the tongue is slightly narrowed at the back. And when we say “s,” the tip of the tongue moves backwards. If the tip of the tongue remains between the teeth, we hear a typical lisp. > > > For human language and vocal structure, the tongue is necessary for producing certain sounds. I don't just want to [re-discuss](https://worldbuilding.stackexchange.com/q/146480/6986) whether a person can speak without a tongue. I know there are animals on Earth [that don't have a tongue](https://www.nationalgeographic.com/news/2015/10/151031-animal-behavior-fish-parasite-anatomy-tongue-insects/#close), but crabs and butterflies aren't exactly known for their linguistic excellence. I want to re-envision the entire vocal structure, from the ground up. Is it possible for a tongueless creature to vocalize the complex sounds of a full language (including learning another language)? [Answer] Contrary to what I've always understood, and scientists believed until recently, parrots and corvids use their tongues to modulate the "vowel" sounds when they mimic sounds (songs of other birds, environmental sounds, animal calls, and even human speech). If a parrot or mynah were to lose its tongue, its ability to "talk" would be limited, though probably not completely removed (just as a human's would be limited, but not completely eliminated). This is because birds' voices are entirely produced with a syrinx -- a much more versatile sound prodution organ than the mammalian vocal fold. The syrinx can, for instance, produce two separate pitches simultaneously, as well as a much broader range of waveforms. This is why, for instance, a parrot can just as easily reproduce the sound of a film camera's shutter and motor drive or a microwave oven's "done" alarm as it can a cat's meow, dog's bark, or "Polly want a cracker?" This vocal apparatus is common to all birds; the limitations on their ability to mimic is in their brain -- sparrows aren't primarily mimics, so they tend to learn one sparrow song and sing that for their entire lives. Crows, mynahs, magpies, parrots and parakeets, on the other hand, are mimics, and all are capable of learning, to some extent, to replicate any sound they hear frequently. A bird's syrinx or similar apparatus, along with some method of changing the shape and length of the resonating cavities connected to it, are likely sources of "tongueless" speech incorporating approximatly the same range of sounds as human speech. [Answer] All you need is an organ that can controllably vibrate and modulate a membrane at high enough of a frequency. For a perfect example of this, look at a speaker. It has no tongue, or mouth, or even lungs for that matter, and yet it can make all the same sounds as the human voice and then some. The reason animals use our mouths at all is because we don't have enough control over our vocal cords to remodulate frequencies fast enough to make certain complex sounds. That is not necessarily a limit of biology, it's just that on Earth, we've never had to evolve to that level of control over something that is easier to do with what is already there. If instead your creatures evolve more like crickets where they use a totally different part of their body to make noises, then overtime and environmental pressures, the control will come. [![enter image description here](https://i.stack.imgur.com/F8G0p.png)](https://i.stack.imgur.com/F8G0p.png) [Answer] Absolutely. If we start with the human vocal tract as a base, without the tongue one could still pronounce voiced and unvoiced bilabial and labiodental trills, taps, fricatives, plain and aspirated plosives, affricates, nasals, and clicks; as well as velar/uvular fricatives, plosives, and nasals. That's at least 40 distinct consonants, probably more. And in the vowel space, you still have rounded vs. unrounded, and modal vs. creaky vs. breathy voice distinctions. That's a weird phonetic inventory, but in terms of size it's very middle-of-the-road for human languages. A tongue is useful for modulating the airstream, but clearly even human anatomy has several other ways of doing that. So, to produce complex sounds with completely non-human anatomy, you don't specifically need a tongue; you just a collection of ways to modulate the airstream, which may or may not include anything recognizable as a tongue in the vocal tract. Birds, although they do have tongues, can do a whole lot with just a syrinx, for example. And if you had a creature with, say, multiple spiracles for breathing, one could easily imagine using sphincter muscles to produce different timbres, and multiple overlayed phonations from different spiracles simultaneously to produce a wide range of distinct phonemes usable for language. And if you want to go even farther afield, you don't even necessarily need a vibrating air column to produce sounds usable for language. Consider, e.g., crickets, which produce a variety of noises through a more violin-like (or perhaps "musical saw"-like) mechanism, by drawing different body parts across each other to induce vibration. Actual crickets don't have a huge variety of sounds that are produced within a single species, but just as a violin can produce different sounds depending on exactly how the bow is drawn, which string it is drawn over, the tension of the strings, and whether you actually draw the bow at all vs. plucking the strings or slapping the body, it is not hard to imagine a creature which produces a range of distinct percussive and fricative noises by the interaction of external body parts equal in size to typical human phonological inventories. As a proof of concept, see [this video](https://www.youtube.com/watch?v=U10yeJRmi38), in which (among other things) the CODA (child of deaf adults) presenter demonstrates how you can in fact *hear sign language*. No tongue required. [Answer] **Animals can already make complex sounds without their tongues**. I think you're just...thinking about the wrong *end* of the animal. There are even humans who are able to control such sounds [to a remarkable degree](https://en.wikipedia.org/wiki/Mr_Methane). One can imagine a vocal system that uses a similar method - the control of airflow through a sphincter or series of sphincters and chambers to produce complex sounds. Now, to the second question of whether they could use this ability to learn another language...I think that would depend ultimately on the quality of sound that can be produced. Ultimately, if the creature's voicebox is just a series of woodwind instruments controlled by air bladders and muscles, it's probably unlikely that it could replicate human speech, but it definitely could create complex language on its own. ]
[Question] [ I am looking for plausible mechanisms to legitimize (or replace) the physics-based weaponry used in the fictional world of my latest story. My story utilizes a range of weapons (like *Starship Troopers*, *Aliens*, etc), including handheld and vehicle-mounted. Ultimately, I wish to avoid common tropes found in SciFi today -- like plasma bolt cannons, phasers, etc -- and seek to provide my readers something new, possibly using other states of matter in the process. ### Assault rifle One idea leverages a coil-gun like weapon (the size of today's typical assault rifle) fed by a backpack filled with some kind of fluids or gases. When the mixed in the gun's chamber, a chemical reaction occurs and the round is launched by magnetic (or some other) means down the barrel. By the time the round exits the weapon, its density has increased -- e.g., by a factor of 1000 -- to the point where even small caliber bullets have a punch like a shot from a tank cannon. ### Ship-mounted cannon Space-faring warships utilize similar-shaped cannons to today's naval battleships, though the ordinance, again, utilizes some unique state found in physics that is devastating (though not planet killing) and could start off as one state (ideally lightweight) and then create a state that can produce the desired effect. Both of these have "hand wavy" power sources that are compact and sufficient to provide whatever power the weapon needs--growing larger as the weapon grows in size, of course. My story is not driving the hard-science angle (such as *The Martian*), but I wish to tap into something science-based to avoid creating generic "death-ray guns" in my story. Sadly, my research has stalled after a couple of months trying to derive something remotely plausible. I've gone down the path of researching ferrafluids, neutron degeneracy, super-solids, and [many other exotic forms of matter](https://en.wikipedia.org/wiki/State_of_matter#Low-temperature_states). To date, I haven't been able to come up with even "hand wavy" SciFi weaponry that passes even my admittedly low bar for believability. Hoping someone with deep physics knowledge would be willing to provide either a quick suggestion or, ideally, work with me to create two "passable" weapons detailed above for my story -- the assault rifle and the ship-mounted cannon. [Answer] You've got two different weapons in your question, but I think they can both be tackled with the same solution: ~~hand waving~~ nuclear fusion. ## Assault rifle The First Law of Thermodynamics says you can't get something from nothing. > > In a closed system, the total mass-energy can neither increase nor decrease. > > > But whoever said this was a closed system? You've got a perfectly good atmosphere just *sitting there*. Your bullets are modified [Bussard ramjets](https://en.wikipedia.org/wiki/Bussard_ramjet), using sophisticated nano-scale hand waving to fuse atmospheric nitrogen, oxygen and hydrogen into ⁵⁶Fe. The main mass of the bullet is teardrop shaped; there is an outer shell with a similar shape, except the leading (pointy) bit is replaced by a funnel. Air is directed in between the main mass of the bullet and its shell, moving 'round the teardrop to the back, where the airflow creates a higher pressure. This is where the fusion takes place; the molten iron that results gets dumped into the hollow inner part of the main mass of the bullet, but the bullet's reached its target by the time this starts to melt the parts controlling airflow. The fusion reactor emits vast amounts of light (and somehow nothing else, other than the iron), which is directed in a tight beam out the back of the bullet; a small elliptical reflector dish attached to the gun (around the barrel) directs the light back towards the place where the bullet will be by the time the light reaches it (flexing as the bullet travels to ensure that this occurs) to impart more momentum to the bullet as well as maintain the intense temperatures required for fusion. This means that the gun gets *all* of the recoil of the heavy, iron-filled bullet that hits its target – but you can carry a lot more ammo, and the recoil lasts the duration of the bullet's flight. None of this intense light enters the barrel, because diffraction, and it doesn't get scattered by the air, because it's been scooped up by the bullet and there isn't enough time for surrounding air molecules to get that close unless it's a *very* hot day. In such conditions, you would be able to see a really bright beam of light – perhaps white, though it'd need to be a pure, single-colour frequency if you wanted to use the "because diffraction" excuse (i.e., if it's visible light, it needs to be a colour of the rainbow). The momentum gained by the energy sent out as light is just enough to accelerate the mass gathered from the air to the same speed as the bullet. The bullet neither speeds up nor slows down – it just gets heavier as it flies. Due to the light-speed limit, there would be left-over *really intense light* that wouldn't be able to bounce back and hit the bullet. If you're willing to suspend some engineering realism, this energy could be captured and stored for launching the next bullet. (I'd need to run the numbers to see how plausible that 1000× figure is, but most of the issues of plausibility there can be fixed by making the initial bullet mass lower. Or perhaps 1000× is an exaggeration for marketing purposes.) In practice, this would look like a gun that fires glowing globs of liquid / gaseous / plasma metal through people with a sound like thunder, and perhaps a flash of *really* straight (perhaps colourful) lightning. ## Ship-mounted cannon It's easy to make a planet-destroying ship-mounted cannon; just make a [Mount Everest-mass black hole](https://qntm.org/destroy#sec3) (something more than 1 Pg should be safe enough to handle without glowing too much) and drop it at the planet in question. okay, maybe producing a black hole isn't all that easy… Destroying *spaceships*, on the other hand, is relatively easy: fire really tiny, *really fast* rocks. Lots of them. Punch holes through everything important. In space, the only thing in the way of your rocks is the spaceship, and people find it hard to survive when their engines are broken and their atmosphere is rushing out of *very* rapidly widening cracks in the hull. (You need a lot of these holes, because there are a lot of airlocks inside a spaceship.) If you want your cannons to fire more traditional cannonballs, instead of really tiny shrapnel… just use hydrogen bombs, then follow up with copious quantities of ClF₃. You will have burning craters, in space, which you've got to admit is *pretty cool*. (If nuclear weapons are prohibited, any powerful explosive will do, and the ClF₃ will become all the more useful.) A combination of these techniques is probably best; put holes through *everything*, but only bomb and burn important stuff like the fight and flight systems. Spaceships are *fragile*. [Answer] **[Tesseract](https://en.wikipedia.org/wiki/Tesseract) bullets.** Imagine a 3 dimensional box made of cardboard. Using a hydraulic press you smash it into 2 dimensions. The flat sheet you have now is considerably more dense than the box that you started with. Your bullets work similarly. They are 4 dimensional objects but tenuously so - they are balanced in their extradimensional extent like a paper clip folded into a spring. On triggering the mechanism, the extradimensional mass of the bullet balanced outside our 3 dimensions collapses over a period of microseconds back into 3 dimensions. The resulting bullet is much more massive and possibly unstably so as the atoms comprising the bullet are packed much more closely than they like to be. It is also extremely cold - pushing the mass out through the 4th dimension to make the bullet takes a lot of energy input, and is functionally equivalent to compressing a gas. On relaxing back to the native 3d dimension it is the equivalent of a compressed gas expanding, and endothermic. --- 4th dimension aside; there is no free lunch and increasing kinetic energy for nothing violates the laws of physics. 1/2mv^2 needs to stay constant. Let us look at some numbers. [![enter image description here](https://i.stack.imgur.com/AoYBJ.png)](https://i.stack.imgur.com/AoYBJ.png) Turning a 1 gram rifle bullet into a 7 kg shotput slows it down to the speed of a fast fastball. It is going to leave a mark, for sure but not blow a hole thru a tank. But if you start with a railgun projectile... [![enter image description here](https://i.stack.imgur.com/xvOL7.png)](https://i.stack.imgur.com/xvOL7.png) 7 kg at 340 m/s is like a cannonball as it exits the cannon. That will be the desired wallop. One could make a case that a wallop is a wallop, so why not just shoot things with the railgun projectile? Possibly because the 1 gram bullet might ricochet, or possibly continue through the target and out the other side, much of its kinetic energy retained. Those issues are less problematic with a cannonball. [Answer] It's not plausible, under science. [The first law of thermodynamics states such-](https://en.wikipedia.org/wiki/First_law_of_thermodynamics) > > The law of conservation of energy states that the total energy of an > isolated system is constant; energy can be transformed from one form > to another, but can be neither created nor destroyed. > > > You can't increase the density of a material without adding more material or changing the volume. If you want a vaguely scientific gun like this, you need a new source of mass. So, have the bullets not be bullets, but a tracking beacon. You fire at a target, and the gun or the ship opens a portal up to a heavier projectile which smashes them. Wormholes are theoretically possible in physics, and so this is appropriately sciencey. In the gun or the ship you could have a coiled ring, which uses powerful electromagnets to accelerate projectiles to immense speeds. When the tracking beacon hits the target, a portal teleports in instantly sending the projectile to the target. [Answer] **AI weapons** The problem with most weaponry today is in order to shoot someone you must give them a chance to shoot at you also. To solve this problem you can create "guns" that fire miniature drones instead. the drone can then seek out and shoot the enemy. If the enemy shoots them down, that is OK, it is just a drone. Normally in that situation your soldiers would be shot, but not anymore. Your large ship weapon can behave in the same way. instead of firing heavy ordinance, the weapon instead is an armored drone carrier that deploys the drones into the enemy ship or over the enemy position. Depending on how small you can get the drones there are two additional benefits, First, they become harder to hit, up to the point where only other AI weapons can shoot them down. Second, if your drone fly with wings and in hordes they can simulate the sound of angry bees. Many armies will stand against your soldiers and tanks. It is hard to hold the line against a mass of swarming insects that are preceded by the sound of angry bees. [Answer] **Criteria** I've narrowed what your looking for down to a solution which meets a few criteria: 1) You are looking for a weapon which is based upon a physical mechanism (non-magical) that can is roughly analogous two modern day equivalents: the Main Battle Rifle (MBR) and Heavy Artillery. 1a) For the MBR I'll use the following restrictions: a small arms weapon capable of being wielded unaided by the average human, is capable of continuous fire, is re-loadable in a modular fashion (if applicable) and is capable of inflicting lethal damage to the average human up to ranges of at least 300 meters. 1b) For Heavy Artillery you mention the addition analogy of navel artillery, capable of being mounted on spacecraft and inflicting severe damage to the constructs on which the heavy artillery are mounted (presumably other spaceships, but not planets). I'll assume that the artillery are not hard guided (no missiles), while some sort of "soft" guidance is allowed in analogy with modern day artillery. For real world analogies, I'm presuming your thinking of 12 - 16 in. guns. 2) The physical mechanism by which these weapons operate is "mostly realistic". Since "mostly realistic" is very open to interpretation, I'll restrict my solutions to only those which do not violate known symmetry laws in physics (most of the Standard Model). Fictional physics I'm assuming can be used, but only as long as it does not violate already established laws. 3) The Physical mechanism by which the weaponry operates is not a common trophe of science fiction. Thus, I will rule out the following: Laser beams, Plasma projectiles or bolts, Gauss guns, "Ray" guns, as well as real life projectiles: metal and polymer bullets, depleted uranium and tungsten bullets and kinetic projectiles. The caveat here is some elements of the above may be used, but only if they are coupled with a mechanism\material which is not typically associated with the weapon system. 4) The weaponry should incorporate unique and unusual physics and/or materials in its' design. Thus mostly ruled out are chemical firing mechanisms and electric firing mechanisms. **Possible Avenues:** With these restrictions in mind I'll present some possible solutions. Unfortunately all of these criteria eliminate a lot of possibilities. I'll start with high levels of handwavium and proceed downwards. A) A fifth force: You can do all sorts of fun stuff with a fifth force without explicitly breaking known physics. As long as the fifth force involves improbable scenarios and as long as that scenario doesn't explicitly violate known laws it can appear plausible: A-1) For example, does this fifth force interact with matter? Perhaps as an interaction between masses but unlike gravity the interaction is strictly repulsive. How is this force triggered, perhaps by running a current through an exotic material. Now you can have a gun whose power is limited by the structural integrity of your material and electric current. Combine this with high-temperature super-conductors and you have one hell of a weapon. Of course the constants for such a field to work have to be just right and you still need to respect conservation of energy, but hey its a fifth force and can be tailored to how you like it. A-2) Of course invoking a fifth force will come across as very contrived to anyone knowledgeable about physics, but it can provide the playground to explore really cool phenomena which can be used for all sorts of other things. Working through the physics of new fields and particles interacting can given rise to constructs well beyond weaponry. This approach is also very conducive to effects and weaponry which is not already (over?) explored in science fiction. B) Less contrived than a fifth force would involve materials and phenomena, but interesting enough be be unique. Superconductivity is an obvious choice which will allow all sorts of electromagnetic weaponry, but this is quite common in science fiction. Other areas along this avenue are explosive propellants which are not commonly used in Sci-Fi and which have no real-life counterpart. For example, inducing nuclear emissions in some exotic material to produce a powerful explosive reaction which could result in more energetic projectiles. While no real cases of induced nuclear emission have been found suitable for this purpose, there have been some proposed cases which might serve for insight into what this phenomena might look like (see Hafnium controversy). C) At the bottom of the rung are possibilities found IRL, unfortunately most of these are already found somewhere in fiction and science fiction. You can have caseless ammunition, Self-guiding (smart) munitions and miniature atomic weaponry. Each of these can be tweaked to be unique but will not appear very exotic. **Where to go:** I would imagine that it would be easier to work backwards than forwards. By this I mean that it would be easier to flesh out a weapon system and some characteristics that this weapon system has. For instance, what does the rifle look like? Does it have any characteristics which stand out? Perhaps it needs a very cylindrical metal chamber, a long barrel and fires what appears to be bright bolts of light. Perhaps it can fire rapidly, but has a serious over-heating problem and is loaded with cartridges containing bullet shaped rods, but no propellant or casing. The more descriptive the more you can contrive some physics by which this sort of weapon could be made. Working forwards on the other hand is not easy if you want to be consistent with the physics. For example, if you want to incorporate an IRL exotic states of matter, degenerate electron matter for instance, this really narrows down what you can do since there already exist very good theories of electron degeneracy pressure and when it is applicable which is essentially only in the conduction band of super cooled metals, or in super dense, high gravity star systems such as white dwarfs. Unfortunately real life physics is very restrictive which I believe explains the tendency of all science fiction, especially the sort which tries very hard to not break existing physics laws, to sort of converge on the same ideas and concepts. [Answer] **use actual guns** With current technology, we can create actual rail guns, actual lasers, and self-aiming guns. The reason we don't is that all those things have large maintenance costs and are hard to justify in combat. Lets say you need special multi-dimensional ammo (a cool idea by the way). That probably needs highly specialized equipment and trained individuals. If the factory that makes those breaks down or is unable to supply you, you are screwed. But if your guns take 9mm or 7.62x51 NATO rounds then you can resupply from allies, local suppliers, or even from the enemy. While the idea of huge over powering weapons is cool, most people who get shot don't say they were glad they were not shot with something bigger, if they can say anything at all. getting shot with a good bullet from a good gun is sufficient in most cases. Also, while these big guns have large power sources, a backpack, and a barrel that requires it to be mostly vacant, normal guns will shoot in extraordinary conditions. There is a reason one of the most popular weapons in the world is the AK-47. In "Lord of War" (2005) they say this > > "Of all the weapons in the vast Soviet arsenal nothing was more > profitable than Avtomat Kalashnikova model of 1947, more commonly > known as the AK-47, or Kalashnikov. It's the world's most popular > assault rifle, a weapon all fighters love. An elegantly simple nine > pound amalgamation of forged steel and plywood, it doesn't break, jam, > or overheat. It will shoot whether it's covered in mud or filled with > sand. It's so easy even a child can use it, and they do." > > > The point is a good weapon will work under any circumstance with minimal maintenance, so your weapons need to do that also. Weapons that require a back pack and management of three resources will always be beat by weapons that can be disassembled by high school drop outs and shoot mud-caked bullets in the rain. [Answer] Your assault rifle is inherently impossible to use. Guns are subject to Newton's third law. If you have a gun that fires a round that hits like tank cannon then the gun recoils like a tank cannon. Your user dies. Your weapon also seems impractical for most combat. Rifles are for shooting at infantry, your round hits with far more force than is needed to kill infantry. While there are repeated stories about the military deliberately designing their rifles to injure instead of kill (to make the enemy take time dealing with the injured) what's actually going on is much simpler: the smaller bullets are lighter, a soldier can carry more stuff. For general combat you always want the lightest rifle that can do the job. Now, sometimes you have to deal with fortifications. You don't do that with your normal antipersonnel rifle, though. (Although some rifles also mount a grenade launcher for this purpose.) The only reason to build infantry rifles that hit like a tank is if you are facing an enemy that requires being hit that hard to stop them. The *Apocalypse Troll* by *David Weber* comes to mind--the heroine carries a hand weapon that hits with the power up to that of a small tactical nuke because her enemies are tank-like cyborgs. ]
[Question] [ I want to create to create a ship that does NOT rely on rotational gravity to have a constant downward force on everything. The people built a g-force generator that does NOT induce gravity, just a force. So, can a gravity generator that uses energy to accelerate objects towards the generator work? If there is a 100 joules of energy that supplied to the generator, it could accelerate a 1 kg object down under 1 $m/s^2$ for 200 seconds. This situation does not regard efficiency or the mass of the generator itself for simplicity. The mathematics are based on energy, mass, and velocity ($E = 1/2 \cdot M \cdot V^2$). Remember, this would be in the void of space. Would this be possible under real physics or would I have to implement a fifth force for this to happen? If it can happen, could it have an inverse square relationship with distance like real gravity? It can work in any way possible if there is one, but the generator has to work regardless of acceleration of the generator itself. For example, the generator works whether it has a total acceleration of 0 $m/s^2$ or 100,000 $m/s^2$. It can work combined with other generators or actual gravitational pulls. [Answer] **You could simulate gravity using electrostatic attraction.** I cannot run the numbers you provided, but electrostatic attraction can be strong in proportion to the charges involved. It is the same principle that causes cat hair to be stuck to a rubbed balloon. It would work even better in space because space is dry and charge could not leak off into the humid air. In an atmosphere, charge can equilibrate across a space full of gas by breaking the gas down into glowing conductive plasma - this is a spark. In space there will be no equilibrating unless the charged surfaces come into contact with each other, and you can prevent that by coating your spacefarers in nonconductive full body skin tight latex suits. Using charge for attraction in space is not purely zany. NASA has a scheme for an "E-glider" - a spacecraft which makes use of these electrostatic forces around asteroids to maneuver. Unlike gravity which only pulls stuff together, charge is more versatile and can be greater or lesser, positive or negative. In the example the charged vehicle maneuvers relative to the asteroid using manipulation of charge. <https://www.nasa.gov/feature/e-glider-active-electrostatic-flight-for-airless-body-exploration> [![E-glider](https://i.stack.imgur.com/lDKeI.jpg)](https://i.stack.imgur.com/lDKeI.jpg) There was no mention of the skintight latex suits in this NASA article, but I feel they were strongly implied. The spaceships will need latex suits too. [Answer] Those already exist, they are called rockets. When astronauts take off from Earth they are iften faced with high G forces (up to 8g if I recall correctly). That is not coming from rotation, nor from the Earth. In fact, if you wish to go anywhere far from here, [a constant rocket acceleration might provide you with some comfort](https://worldbuilding.stackexchange.com/a/125274/21222). A constant 1g from the engine will keep your bo es healthy and take you to other star systems relatively quickly. [Answer] # There's a reason why the centripetal gravity ring is so popular Here's your spaceship: [![terrible spaceship drawing](https://i.stack.imgur.com/KpFbL.png)](https://i.stack.imgur.com/KpFbL.png) *Note: I am not an artist.* ### You start by accelerating weights [![enter image description here](https://i.stack.imgur.com/aRzoa.png)](https://i.stack.imgur.com/aRzoa.png) If you accelerate a 1 $kg$ weight downwards at 1 $ms^{-2}$, you'll exert a force of 1 $N$ on it. Now, that 1 $N$ gets distributed across the mass of the entire spaceship. Let's say it weighs 50,000 $kg$. This means that the acceleration will be 0.00002 $ms^{-2}$, roughly 2 millionths of Earth's gravity. You won't even notice that. In order to provide Earth gravity to a spaceship that big (which is a realistic size for what you're looking for), you'll need 500,000 $N$ – the equivalent of launching a 500,000 $kg$ mass down at 1 $ms^{-2}$ (which is rather impractical, since it weighs more than your ship) or launching a 100 $kg$ mass down at 5000 $m s^{-2}$. ### Now you're accelerating your whole ship You're now launching a huge mass at a huge speed downwards. As Renan mentioned in his answer, this is starting to look like a rocket engine. But the problem remains: now that you've sent that thing flying downwards, you're not getting it back. You've just lost 100 $kg$ and your gravity has ended as quickly as it began. So you need to continuously launch huge masses at huge speeds. This is going to have the side effect of pushing you in the other direction, really fast. In fact, to get 10 $ms^{-2}$ of pseudo-gravitational acceleration, you need to accelerate at 10 $ms^{-2}$ upwards. [![enter image description here](https://i.stack.imgur.com/9k4QN.png)](https://i.stack.imgur.com/9k4QN.png) So unless you want your gravity generator to fling the ship around (...it's literally a rocket engine!), you'll have to flip the ship around and go the other way for a while. That way, you spend a few minutes accelerating one way, then have a short zero-g break while you rotate, and then spend a few minutes accelerating the other way. Don't try this while docking. [![enter image description here](https://i.stack.imgur.com/YAxry.png)](https://i.stack.imgur.com/YAxry.png) ### And now you're swinging back and forth So you ideally want to avoid the zero-g period while you flip the ship. So you keep the gravity generator (aka rocket engine) on the bottom of the ship and leave it running while you turn. So you spin around in a spiral pattern, always accelerating upwards relative to the people. You want to make the spiral as circular as possible, because a perfect circle wouldn't change the trajectory of the ship, whereas anything else would. So you add side thrusters and spin around in a controlled circle, spending equal time accelerating in every direction. ### And now you're orbiting a point. Your main issue now is that you're throwing out all this mass and not getting anywhere. Bear in mind that you have to carry all these weights with you everywhere you go just to have gravity. So instead of constantly launching the weights, you keep one big weight, heavier than the ship (maybe it's a fuel tank or something), and tie the spaceship to it using a long cable. That way, the spaceship swings around the weight like a sling, creating the same circular effect, but you don't burn any fuel. [![enter image description here](https://i.stack.imgur.com/90HK9.png)](https://i.stack.imgur.com/90HK9.png) But your ship pulls on the weight in the middle, and swings it from side to side. So for balance, you put another equally heavy ship on an equally long cable on the other side. Now it's like a 2-bladed ceiling fan: the symmetry prevents it from wobbling. [![enter image description here](https://i.stack.imgur.com/frvOL.png)](https://i.stack.imgur.com/frvOL.png) Now, you probably see my point. If you don't want your generator to fling you chaotically around space, the best solution is a rotating centripetal gravity system. I know that's not what you asked for, but your gravity generator is literally a rocket engine. If you want gravity while the ship isn't burning its engines, you need one of these: [![enter image description here](https://i.stack.imgur.com/lWII5.png)](https://i.stack.imgur.com/lWII5.png) ]
[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 2 years ago. [Improve this question](/posts/135692/edit) Restated in more words, would a conscripted pikeman with a decent set of chainmail but no shield have any hope against an arrow from your basic english longbow? [Answer] This depends a lot on the arrow and type of chainmail. the draw of the bow (english longbows do not have a standardized draw) also matters. A broadhead hitting an 8 ring mail wouldn't yield much more than a scratch, a spike bodkin will go right through 4 ring mail and barely notice the armor. Image of different chainmail types below. 4 ring is by far the most common (~97-98%) but examples of 6 and 8 ring do exist. there was even something called doublemail but no one knows what it was, I personally suspect it is either 8 in 1 or another name for kingsmail a variation of 4 ring in which every ring is doubled called [8 in 2](https://artofchainmail.com/patterns/european/kings1in8.html). Keep in mind you don't wear chainmail by itself but with padding below it which also matters. If the archers know there will be armored targets they will be using bodkins which are very good at penetrating chainmail (and armor in general) of course the downside of these arrowheads is they don't cause all that much bleeding meaning they take time to kill someone most of the time. [![enter image description here](https://i.stack.imgur.com/0dBqN.jpg)](https://i.stack.imgur.com/0dBqN.jpg) [Answer] Broadhead arrows - definitely, it would. Bodkin arrow - probably yes. It depends on many factors like distance between archer and his target, angle of impact, draw of bow, etc. But even if an arrows penetrates the mail, it will not kill the soldier wearing it. Because of gambeson under the mail. And gambeson is an amazing thing, it can deflect blows even arrows (if you are lucky), it´s cheap, available and easy to produce. It´s also possible to wear second gambeson over the mail to increase protection. [Answer] If the pikeman was 20 yards farther than the maximum range of the bow he would be safe from that shot since it wouldn't even reach him. In the US Civil War bullets would slow down as they traveled farther and farther and would eventually be what was called "spent rounds" shortly before falling to the ground. Many soldiers survived being hit by spent rounds without serious injury. If the same thing happened to arrows then there would be distances where arrows from even the strongest bows couldn't reach, closer distances where unarmored men wouldn't be seriously injured by arrows, closer distances where men in mail were safe but unarmored men would be seriously wounded, closer distances where arrows penetrated mail and inflicted serious wounds but couldn't penetrate plate armor, and perhaps closer distances where arrows might penetrate even plate armor. And perhaps someone who is more of an expert on medieval archery will be able to tell you what those ranges would be. [Answer] Another factor is the arc at which arrows are loosed. At Agincourt, the archers nocked and drew but held their arrows until the mounted French, closely packed on an ever-narrowing uphill approach, were all but bearing down on them. Thus, they loosed at steep an angle, that their arrows, tipped with heavy spiked and bevelled bodkin points, struck that target-rich enviornment at terminal velocity, finding first the visor slots in helmets of the many inexperienced French "only yesterday made knights" who turned their faces upward to watch their death come down to claim them. For the more experienced wearing good plate, the deadly points battered helmets and armour like hailstones, then richoeted downward driving into the unprotected necks, withers and haunches of the huge destriers. The massive horses, wounded and panicked, went down, taking their hapless riders with them into the quagmire where they were trampled by following ranks now pressing forward, or kicked literally to death by their own dying mounts. And herein lies the rub: a long bow could be nocked, drawn and loosed in rapid succession, much moreso than the crossbows favored by the French, so much faster, in fact, that the practiced English bowmen could attain a rate of loose at 8 arrows per minute. History records that, at Agincourt, the third volley was in flight before the first volley struck home. And the rain of feathered willowwood and steel was relentless, whittling away the French forces in the dozens with every volley. [Answer] Have a look at these two videos they may help. They're from a YouTube channel called **Tods Workshop** and he (Tod Cutler) actually has a business making realistic (period) arms and armor. The two clips are part one and two on the same subject. **The historic effectiveness of bows against chain mail**. For these videos best as possible Tod re-creates (or gets from others) the armor samples and arrows used in the test. These are all made with the materials and techniques we 'think' medieval craftsmen used based on archeological records and historical texts. (Note he's using modern crossbows for the test - for reasons explained but he has done similar experiments with historical long bows). In any case the tests being done were designed to answer a specific question. Namely how effective was chain mail armor at stopping projectile weapons (arrow and bolts). So it other words your question! Hope it helps. [Part 1, arrows vs mail](https://www.youtube.com/watch?v=5iBWI7Q7LVI) [Part 2](https://www.youtube.com/watch?v=8z1V8fgfP30) ]
[Question] [ Instead of Earth as we know it, humans evolved on a slightly smaller, habitable earthlike planet with different geography. Due to the plot reasons, I would like to keep them confined to one (large) continent with no seafaring until they achieve late-19th century tech level, delaying the age of discovery (this world contains other significant lands, but they should not be discovered by mankind too early). But how can I achieve this? I was thinking mostly about the geographical reasons so far, and came up with following: * the sole inhabited continent should be remote from all others (pretty obvious) * strong currents along coast making seafaring in small boats dangerous (and without mastering the small boats, large ships will not be developed) * the coastline should be relatively simple, with no peninsulas and significant islands - pretty much like Africa in our world * ideally, the coastline should be a barren wasteland with no trees and Atacama-like deserts, so humans will have little incentive to live there and experiment with boats (and no building material for boats in the first place) * no big lakes to experiment with boats inland * fertile lands, where human civilization developed, should be locked deep in the continent's interior, ideally separated from the coast by mountain ranges and deserts Is it believable, that such conditions may prevent humans from becoming sailors and expanding to other continents? What else can I do? [Answer] # Shipworms Your planet has a very effective species similar to [Teredo](https://en.wikipedia.org/wiki/Shipworms). They destroy any wooden hulls in a few days or weeks. You can adjust the description of the species to prevent ocean travel but not river/lake travel by making it a saltwater species. * An iron or steel hull would be immune. * If there is river travel, you have to explain why simple [coppering](https://en.wikipedia.org/wiki/Copper_sheathing) is not effective. + The worms are tiny and get into cracks? + The worms can live out of the water for a short period and climb up the hull? [Answer] # Release the Kraken ![That's one loving big calamari](https://i.stack.imgur.com/Alh71.jpg) I believe this is self explanatory. To add some variety, look at the [Carta Marina](https://en.wikipedia.org/wiki/Carta_marina), a map of the nordic lands from 1519. It contains a plethora of other sea monsters, such as these: ![Sea monsters](https://i.stack.imgur.com/D8lk6.jpg) Because medieval waters were to sailors what current day Australia is to land dwellers. [Answer] I do not think you can prevent boat use on rivers and lakes. People will see broken trees floating on them, then tie them into rafts, then start shaping them. You can limit coastal boating with severe seas (Iceland comes to mind). Or make water much more salty, making sea-food inedible. Also based on Iceland, minimize or eliminate tall trees. Just have plains, marshes, moorland. No trees = no big boats. They can still make rafts from bundles of grass, but they fall apart in rough seas. Make other continents small and locate them far from main continent. And have winds and currents that make it hard to reach them. So reaching other lands in sail ships is very hard, and finding them is harder, and getting back is nearly impossible. Since nobody ever returned with news of other lands, people just assume that there is nothing to explore. Also make travel within the main continent easier. RL exploration started as an easier way to get to India (which was known, but hard to reach by land). SO: Lots of long wide rivers, few mountain ranges or deserts. You could also have internal seas or lakes, but that encourages big boats. [Answer] **There are no trees suitable for shipbuilding** Wood was pretty much the only game in town for seafaring until metal ships became practical. Without proper wood, there would be no sea travel until about the industrial age. This of course can cause problems in other areas where wood was crucial, but for most things there are suitable alternatives: buildings would be mostly earthen/stone/thatch, abundant coal could provide easy fuel, etc. [Answer] on a planet with a large nearby moon, tidal forces would be immense. in such a situation, or perhaps a climate heating scenario inducing similar instability, hurricanes would be frequent, even constant, rendering coastal living unsustainable. as a result, the populace lives inland, away from the worst of the storms. in such an environment, reliable sea-travel might have to be submarine, which would require a great deal of industrial/technical development before being developed. seamanship could still be developed in inland lakes. a continent without water-shed in the form of rivers & lakes makes no sense. [Answer] There are two challenges posed by your question. ## Early migration The first relates to early human migration. Of course, we know that the European "age of discovery" involved very little discovery and that actually most places "discovered" by Europeans between the 15th to 19th centuries were already inhabited by homo sap communities. Therefore, you need to think about what stopped humans from spreading out across your world in its prehistory. Isolation of your inhabited continent won't do it: Polynesians and Melanesians used small outrigger canoes to settle islands thousands of kilometres apart, thousands of years ago. **Rather than looking for environmental or geographic reasons to impede seafaring, why don't you establish a culture that is, for some reason, historically averse to travelling over water, or exploration, and then an event in recent history which changes that?** ## Preconditions for industrial revolution The second challenge relates to the implications for industrialisation if you remove seafaring. I am referring here to to mercantile capitalism and the global networks of exchange that emerged as European powers started to develop technologies such as square-rigging and establish themselves overseas; seizing new natural resources, exploiting new labour forces, creating new markets, etc. The fundamental problem is whether the industrial revolution would even have been possible without this prior stage, and I would argue that it would not have. Look at China, the empire of a thousand year dynasties that has more often than not been ahead of the pack throughout history. The Haijin policy of maritime isolationism following Admiral Zheng He's expedition to Africa in the Ming Dynasty inhibited China's participation in mercantile capitalism - and therefore the institutional (in terms of property rights, etc) and technological developments that laid the foundations for industrial revolution. Result is that China has only recently "caught up" with the countries that had their industrial revolutions earlier. Think also of cotton, the driver of the industrial revolution across Europe. Cotton's story is inherently one of mercantile, globe-straddling war capitalism: labour ripped from West and Central Africa, transported across the ocean to the Americas to work as slaves growing high-quality cotton on fertile grounds seized by Europeans from native populations, all in order to undercut Indian growers, spinners and weavers and ensure the domination of merchants in London and Antwerp, and mills in Liverpool and Alsace-Lorraine. The golden age of cotton was borne of seafaring, a triangular trade: finished cotton goods from English mills to African traders for slaves, slaves sold to the Americas where ships loaded raw cotton that was then transported to European centres of cotton production. Without seafaring, would the mechanised mills that powered the industrial revolution have come to pass? **I think this is a harder challenge to meet. To create a realistic, early-industrial world absent seafaring will require you to generate a material, political and technological history that meets the conditions of Earth's mercantile period but unfolds across one continent only.** [Answer] If in doubt always go with Religion to explain reasons for the impossible. Early Civilisation - Death by drowning sends your soul to hell or some other bad place and no one wants that or to even risk it. Later Civilisation - Religion from Early Civilisation is cast down - someone learns mouth to mouth resuscitation. [Answer] ## Radioactive oceans For some reason, your oceans are full of radioactive isotopes. No one can survive a sea voyage for very long, and people avoid the coast in general. In the equivalent of the 1800s, experiments with sea water lead to useful shielding techniques, boats with no direct sailor exposure to the sea, and medical treatments (Iodine, etc). Maybe the coasts have hundreds of kilometres of slightly radioactive marshes instead of deserts in some places. [Answer] Assuming that most of the population lives in the fertile centre of the continent, travel in the fertile areas is easy, there is next to no food on the coast, fishing is limited due to the currents, the coast is difficult to reach due to mountains, deserts, noxious gas fields, swamps, dense woods, ect. and the coast can't be seen from the fertile areas, I can think of two solutions: **Cultural/Religious fear of the coastline** You could have a cultural fear of coastal living and seafaring. After which an industrial revolution could also be tied with a cultural revolution which opens up the idea of seafaring. As an example lets say long ago a group of people left for the coast to and attempted to live there, they failed. Their failure became legend and what could have in reality been them running out of food in a minor rainstorm would become an apocalyptic flood. Since it is difficult to go to the coast in the first place paired with the now legendary events of the last attempt people would rarely attempt such a voyage to the coastline out of a mix of fear, impracticality and going to the coast being outside of the norm. Industrialization implies transportation improvement which in turn will make it easier to get to the coast and eventually it becomes practical to travel or live in coastal areas, the legends become outdated as more and more people are able to travel to and even live near the coastline. From the post industrial point where the legend has little to no weight in peoples lives and it is relatively easy in the first place to live on the coast, coastal life would likely resemble what it is like IOW. **What's there to do on the coastline (Logistical lack of settlement)** This is the most simple, it seems right now that it is very hard to get to the coast due say there was also highly limited food on the coast (few to no edible plans, sub par soil, fishing is too difficult due to the currents), to the point of any coastal settlement would be entirely dependent on the internal fertile area for food and basic goods to survive. In this scenario there is no real way of living near the coast itself, it becomes likely that people simply won't spend much time there. If there are no long term settlements then no maritime industries will develop, thus no real ability to make or launch ships capable of trans-continental travel. After industrialization settlements can be properly supplied due to advances in transportation technology. Since there are coastal settlements it becomes possible to have maritime industries, starting with coastal boats and eventually building ships capable of trans continental travel. ***Long story short:** It is still possible to live on the coast but is a very challenging life thus people tend to avoid it and those that do not are too busy surviving to attempt trans-continental travel.* [Answer] ## **MAKE THE SUN SLIGHTLY SMALLER** Assuming this earthlike habitable planet is slightly smaller than Earth, let's also assume the Sun may be smaller too, and according to this [Tidal locking of habitable exoplanets](https://link.springer.com/content/pdf/10.1007/s10569-017-9783-7.pdf) paper, let's assume this smaller Earth is now tidally locked to this smaller Sun. Also assume terrestrial life on this tidally locked planet is not located at the permanent terminator or twilight zone, but rather is it gathered at the only hot enough place, under the zenithal cap, on a massive single continental mass concentration born from some earlier planetary formation's major impact. Most of this tidally locked Earth is covered by an ocean of ice, with a circular ice wall that circles the habitable landmass. The shore is a desertic frozen steppe, its vegetation gradually growing along temperature and sunlight. Driven by convective forces, strong constant cold winds come from the ocean towards land, and raise to turn back at high altitude, building a constant donut shaped local wind pattern, happily disturbed by libration of the planet, helping life shaking and emulation, chemical soup mixtures, aerial transport. Exploring against the wind towards this frozen ocean followed by a perpetual darkness is hard and may require fossil energy. [![enter image description here](https://i.stack.imgur.com/yjt84.gif)](https://i.stack.imgur.com/yjt84.gif) [Answer] ## Doldrums On your world, the ocean winds are too weak for anyone to develop sailing ships in the first place. (Maybe the open ocean does have sufficient winds, but they don't start until 20-50 miles from shore, so nobody even knows about them.) As a result, ocean exploration doesn't become a thing until industrialization, and steam-powered engines, come along. I don't know enough about geophysics to come up with a plausible reason for the lack of ocean winds. (My first thought was that perhaps there's *no* moon, but it sounds like [that would make the weather worse](https://listverse.com/2019/04/23/10-changes-the-earth-would-suffer-if-it-had-no-moon/).) But you could probably handwave it by saying it's something about the shape of the ocean floor and what that does to the major ocean currents. ]
[Question] [ Some of what I read in [How could a 4D organism influence events in our world](https://worldbuilding.stackexchange.com/questions/68903/how-could-a-4d-organism-influence-events-in-our-world/68908#comment314235_68908) made me think in a different direction about a question I asked before. I'm trying to create a large sphere shaped field of gravity, without a physical mass at it's center, that floats in space. Inside the field would exist a habitat that humans could live in. Basically a massive ball of air held together by this force in what I imagine would be a microgravity situation. I already assume this couldn't be found in nature. I guess it would have to be some kind of super science. How could the physical mass be "elsewhere" but it's gravity be felt "here"? Could something exist in another dimension or reality but exert its effects in our reality? EDIT: From <https://www.nationalgeographic.com/science/space/dark-matter/> "One leading hypothesis is that dark matter consists of exotic particles that don't interact with normal (baryonic) matter or light but that still exert a gravitational pull." Does that help with ideas? Adding onto edit 1: <https://www.space.com/33850-weird-galaxy-is-mostly-dark-matter.html> From the article: “Motions of the stars tell you how much matter there is," van Dokkum said in a statement. “They don’t care what form the matter is, they just tell you that it’s there. In the Dragonfly galaxy stars move very fast. So there was a huge discrepancy: using Keck Observatory, we found many times more mass indicated by the motions of the stars, than there is mass in the stars themselves.” In other words, van Dokkum and his team found evidence of way more mass than they could actually see. OR EDIT 2: Could the use of massless particles lead to an answer? <https://en.wikipedia.org/wiki/Massless_particle> EDIT 3: A version of String Theory known as M Theory suggests that separate "branes" interact through gravity (The central idea is that the visible, three-dimensional universe is restricted to a brane inside a higher-dimensional space, called the "bulk"). Could something along these lines be an answer? [Answer] **1. You could have the gravity produced by a big wad of [dark matter](https://en.wikipedia.org/wiki/Dark_matter)** > > Dark matter is a hypothetical type of matter distinct from ordinary > matter such as protons, neutrons, electrons, and neutrinos. > > > Dark matter has never been directly observed; however its existence > would explain a number of otherwise puzzling astronomical > observations. The name refers to the fact that it does not emit > or interact with observable electromagnetic radiation, such as light, > and is thus invisible to the entire electromagnetic spectrum. > > > Although dark matter has not been directly observed, its existence and > properties are inferred from unexplained mass in gravitational lensing > calculations, which affects the motions of baryonic matter and > light. > > > Given that light and radiation pass through dark matter (but the path of radiation can be bent by the gravity of dark matter) it may be that other things pass right through also - like people. Dark matter might only have gravity. **2. Gravitational mass not in 3D plane.** Consider a 2D world. I am a flatlander and there is a large 2D mass as well - perhaps a big circle. The gravitational forces between us can be expressed as a vector. The vector can be considered a sum of X and Y vectors. Now a 3D world. I am here, and so is Earth. The gravity between me and Earth can be expressed as the sum of X, Y and Z vectors. Depending on how you want to make gravity work, you could have extraplanar objects exert gravity. In the 2D world, if a 3D sphere intersected it the flatlander would perceive it as a circle. You could have gravity exerted along X and Y vectors by only the mass of the sphere that was within that 2D plane. In this case it would not be possible for me to experience gravity from something which was not in the same plane as me. Or - you could have extraplanar objects exert gravity on things not in their plane. The entirety of the mass exerts gravity as is the case between me and Earth. For the Flatlander the entire 3D mass could pull, but only the X and Y vectors would be relevant. A Flatlander cannot be pulled out of its 2D plane and so the Z vector is irrelevant. To calculate the pull of a 3D object out of plane of the 2D object one would calculate X Y and Z vectors then drop Z. So too your 4D object. If you have gravity work this way an extraplanar 4D center of mass can exert gravity on a 3d object via X,Y and Z vectors but not "A", which would pull me out of my 3D plane. It does not have to be a 4D object exerting gravity on me. It could be an ordinary 3D object but not in my 3d plane. An interesting speculation: perhaps dark matter (that has only gravity) is actually normal matter which is not in the same 3D plane as us, but can exert gravitation influence on objects in our plane. A 3d star in a 3d plane "adjacent" to mine via the 4th dimension could exert gravity on me but I would not see its light or feel its heat. **3. Bent space.** from <https://physics.stackexchange.com/questions/3009/how-exactly-does-curved-space-time-describe-the-force-of-gravity> > > There are actually two different parts of general relativity. They're > often stated as > > > 1. Spacetime tells matter how to move > 2. Matter tells spacetime how to curve > > > Gravity is actually a product of locally warped spacetime. Spacetime warps because of matter in it. I recommend the linked article on the physics stack for those interested. Could spacetime get warped absent any matter? I am thinking of the dent a cat leaves on a pillow. When the cat leaves the dent stays. Of course curved spacetime is kept curved by the presence of matter and uncurves as the matter moves on. But what if there were a piece of spacetime that like the pillow stayed curved even though the cat has left? This "bent" would produce gravitational effects despite there being no mass - it would only be spacetime telling matter how to move. Sort of spooky but maybe appropriate for concept-driven high SF. [Answer] What you're proposing can't work. If you contain the sphere of air via gravity as you are thinking, the gravity will necessarily pull on all matter equally at any given range. As a result, denser things (like, say the human inhabitants) will be pulled toward the center and the air will not provide sufficient resistance for them to stop themselves. Therefore you would either need a physical mass for them to stand on or have them constantly expending energy fighting gravity via some kind of personal propulsion system... Or, I suppose, just live with the writhing ball of flesh at the centerpoint... Perhaps they take turns being the floor... If your goal is for humans to be able to fly, there are two approaches that come to mind: 1. Some kind of membrane or forcefield to hold the air in without providing gravity. Given that you don't like the idea of a solid barrier, probably the latter. Maybe some kind of gravitational lensing effect heretofore unobserved? Make the gravity that holds stuff in only be in effect at the periphery of the sphere. Probably wouldn't do good things to anyone passing through it though. 2. An environment similar to the one in Larry Niven's "The Integral Trees" where the cloud of atmosphere takes the place of the rings of a gas giant. That gets you a source of sufficiently strong gravity to hold the air in, but puts it in orbit so the inhabitants don't all pile up in the center. Such a system would not be stable in the long-run, but long-run on celestial timescales is plenty long enough for humans to live in for quite a while. [Answer] Space habitats meant for humans to live in may well have [artificial gravity](https://en.wikipedia.org/wiki/Artificial_gravity) without any mass whatsoever in the center. All you need to do is spin the habitat - the faster it rotates, the greater the [centripeal force](https://en.wikipedia.org/wiki/Centripetal_force) generated by this will be. So as long as you have an habitat with a hollow center, you're good - after all, your humans will need rooms and restrooms and everything, right? They are not just going to float in space. If you don't like the idea above, and you want to generate gravity without mass... You can do that, but you are going to need an humongous amount of energy. In general relativity, gravitational fields are generated by [the stress-energy tensor](https://en.wikipedia.org/wiki/Stress%E2%80%93energy_tensor), which is a property not exclusive to matter - radiation also has it. Therefore, energy has its own gravity as well. Get enough energy on a point (through concentrated radiation, i.e.: visible light lasers) and you may start feeling the pull. The problem is how much is enough, really. The equation you are looking for is the famous E = MC2 one. So, to feel a pull equal to Earth's surface gravity, from a point that is one Earth radius away from you, you would need approximately... *M = Earth's mass = approx. 6 x 1024 kilograms* *C = Speed of light = approx. 3 x 108 meters per second* *E = Energy required = MC2 = approx. 6 x 1024 x (3 x 108)2 joules* A back-of-the-napkin calculation suggests an energy amount of 3.6 x 1041 joules. That is 8 orders of magnitude greater than the [power output of our sun's core](https://en.wikipedia.org/wiki/Sun#Core) for one Earth year, so a set of lasers with a total power of a one hundred billion sun cores aimed and focused at a small region in space for a whole year will give you the energy amount you need. I think it is reasonable to expect that any civilization capable of such a feat would have the means to keep the energy contained in that point. Edit: [see Daffy's answer](https://worldbuilding.stackexchange.com/a/104212/21222). If the region in space holding the energy is small enough (30 cm radius or less), you will generate a black hole. That will not bode well for the habitat, as anything that crosses the hole's horizon (including air) is practically lost forever. [Answer] You could have your pocket of gravity be created by energy instead of mass. Photons have no mass, but are affected by gravity, and they create their own gravitational field. The energy of a photon is $E = \frac{hc}{\lambda}$. $h$ is Planck's constant, $c$ is the speed of light, and $\lambda$ is the photon's wavelength. So a single ultraviolet (Extreme ultraviolet, 100nm) photon has the energy of [about 2 nanojoules.](https://www.wolframalpha.com/input/?i=((6.62607004%20*%2010%5E-34%20m%5E2%20kg%2Fs)%20*%20(299792458%20m%2Fs))%2F(100%20*%2010%5E-9%20nm)) We can rearrange $E=mc^2$ to be $m = \frac{E}{c^2}$. So each photon has a relativistic mass of [2.2 \* 10^-26 kilograms.](https://www.wolframalpha.com/input/?i=(1.98+*+10%5E-9+joules)%2F((299792458+m%2Fs)+%5E+2)) That means it creates the same gravitational field that a particle of that mass would create. So to create earth-like gravity, you need to match 6\*10^24 kg. That will take [about 2.73\*10^52 particles.](https://www.wolframalpha.com/input/?i=(6*10%5E26)%2F(2.2*10%5E-26)) So great, we have an earth-like gravity with no mass. But the photons will fly off in all directions right now. So you have two options. 1) Sci-fi a way of containing them. (magnetic fields, strange technology that's unknown to your charactors, etc) or 2) collapse it into a kugelblitz black hole. The Schwarzschild radius is the "radius of no return" for black holes. If you collapse a mass to be smaller than its Schwarzschild radius, it'll become a black hole. The Schwarzschild radius is given by the equation $r = \frac{2mG}{c^2}$ where $G$ is the gravitational constant. Given a mass of 6\*10^24 kg, your photon planet will become a black hole if you crush it into a ball with a radius of [about 30 centimeters.](https://www.wolframalpha.com/input/?i=(2(2*10%5E26%20kg)(6.67408%20%C3%97%2010%5E-11%20m%5E3%20kg%5E-1%20s%5E-2))%20%2F%20((299792458%20m%2Fs)%5E2)) Keep in mind, it'll still have earth's gravity, and getting too close to the center will spaghettify you, but at earth-surface-like distances, it'll feel identical. Except for, you know, the lack of anything to stand on and all. [Answer] Make it a bubble of Time. Time and Gravity go together. If you slow down time just a tiny bit, you will create a gravity field. Gravitational Time Dilation is part of Einstein's theory of Relativity. The closer you get to an object of mass, the slower time moves for you. Want to have the effects of mass? Find a way to slow down time. [Answer] If you're looking to create an air-planet, have you thought about setting it in a nebula, and part of it just happens to meet Goldilocks conditions? Or what's wrong with having a nitrogen-oxygen gas giant? Here's a reddit thread about it: <https://www.reddit.com/r/askscience/comments/1gyivr/could_a_gas_giants_atmosphere_be_composed/> ]
[Question] [ **Closed**. This question needs to be more [focused](/help/closed-questions). It is not currently accepting answers. --- **Want to improve this question?** Update the question so it focuses on one problem only by [editing this post](/posts/100313/edit). Closed 6 years ago. [Improve this question](/posts/100313/edit) A small group of alien biologists and scientists land on earth. They want to study us earthlings and our culture, society, etc. But they do not want to interfere with us, so they have to come up with a way to be able to study us up close without being noticed by us. But these aliens do not have cloaking devices small enough to be used on anything other than ships. What technology could they use to go unnoticed by the human population? [Answer] Without even advanced tech, there are billions of cameras recording the public, billions of phone conversations going on, and no telling how many stored videos easily available for every kind of human interaction (including every form of sex, fighting, talking, humor, etc). Internal cameras surveil inside of buildings, workplaces, prisons, etc. Tapes are stored for years. No matter what the aliens look like, they can watch anything from a dog's birthday party (filmed on the corner of my residential block) to sex to somebody literally being beaten to death. Or a board meeting, if you want that. Or Congress, or sports, or an actual autopsy in medical school. [Answer] It depends on the aliens; if the are visually similar to humans(or their technology allows them to do so), they could hide in plain sight using disguises; if not, they could set up potentially set up remote surveillance which they could monitor from a safe place. If they don't need to be directly there, they could hack into our networked devices (Smartphones, webcams, Google Home/Amazon Echo equivalents etc.) or simply connect to the internet, many people put a surprising amount about their life online for anyone to see. [Answer] As an extraterrestrial visitor and xenoanthropologist, I have had some success in this matter. My people look like miniature haystacks, about 10 cm wide and 4 cm high, in various colors of red, brown, tan, and white. I personally am a sort of pale yellow. We usually eat only at long intervals, but between meals we can wave our tendrils around and draw some nourishment from the air. We are spread quite thin over the populated worlds and there are fewer than a dozen of us on Earth. When I first arrived I mostly watched people at a distance, from static blinds, usually on a window ledge or in a tree. For the first three years I didn't dare move except on Hallowe'en. During the fourth year a pair of bluejays made a nest in me. My advisor came 850 light-years to see if I was still alive. Then I accidentally discovered that sometimes when I touch a human, I can influence his decisions and behavior. I'm not sure, but I suspect it eventually destroys the human's attention span. I don't know what my ethics committee would make of that because I haven't told them yet. For the last twenty years I've been riding around on this guy's head and observing you all up close. I've made him take me everywhere, business negotiations, board meetings, we've been on TV, Jimmy Fallon, Charlie Rose -- I have so much data I'll be writing books for years. You'd think somebody would notice a haystack alien riding on the head of a public figure, but so far I'm getting away with it. You Earth peoples is so dumb. EDIT OMG I am so sorry so sorry I did not mean for this to happen. I just wanted him to take me to meetings with powerful or famous or influential people so my thesis would be more interesting. I honestly did not know what I was getting him into until we were *actually riding down that escalator*. At first it was just a lot of fun making him yell out nonsense slogans and hearing the stupid crowd go wild. But it felt so good that after a few months I wanted it to never stop. Evidently my people get addicted to certain strong pleasant stimulations in the humans we ride around on. Before I knew what was happening, my other colleagues on Earth were getting high on human adulation too. My collaborator in the U.K. is particularly out of control. Our supervisory committee has become aware that something unethical is happening here but it will be almost five years before they can stage any sort of intervention. I am so sorry this happened. Once my colleagues and I get clean and sober I promise that my people will come back and fix up all the damage we've caused. [Answer] ## Not to be too simplistic, but humans are a noisy bunch... We've been throwing electromagnetic energy into space for quite a few decades now. Radio, TV, Internet, Satellite, Microwave, X-ray, you name it, it's still propagating out there in the great void. They would only need to setup a few receiving dishes in various locations covering different frequencies, and they could tap into pretty much most of the history of the human race, especially if they managed to link into the internet and/or have an FTL drive. Sending a stealthy drone in to add a transmissions link onto one or more satellites would give them said internet access. To be honest, overcoming the language barrier again, and again, and again would probably be more challenging than tapping into our signals, at least until they figured out the dictionary apps we've already made. [Answer] **Step 1** The aliens take a look at the encryption protecting our banking systems. Once they stop laughing, they make themselves squillionaires. **Step 2** They use their new wealth to get into real estate. Working through proxies (law firms and real estate agents) they buy apartment buildings, offices, shopping malls, hotels, schools, creches. **Step 3** They use their UltraExtremeNoLimit credit card to buy millions of smoke detectors etc. & use their ship-board 3d printer to add their alien science snooper sensors. This is a *lot* of work, but hey, grad students! **Step 4** They re-package the modded products and have their real estate corps maintenance crews install them everywhere. **Step 5** Their paper to the Intergalatic Social Sciences journal has a squillion byte appendix detailing every moment of the lives of 300M earthlinks is rejected by all referees as being unsupported by sufficient data. [Answer] Even if a cloaking device is so large that it needs to be housed in a structure as large as a ship, they could still build that large device on the ground (bringing in parts via transporter, cloaked shuttle craft, or building it in the middle of nowhere and then tunneling to where they need to be to observe). This is was what the Federation did in the Star Trek episode [Who Watches The Watchers](http://memory-alpha.wikia.com/wiki/Who_Watches_The_Watchers_(episode)) -- they built an observation post hidden by a holographic wall (and then the holographic generator failed, exposing the observation team, so make sure you have a backup cloaking device). [Answer] *Biological Robot Bugs and Other Creepy Crawlies* Bugs of some sort already exist in nearly every habitat Earthlings are found. They are small, many equipped with antennae already, and lots can fly, providing great 360 measuring opportunity. They are light enough that when the Earthlings are sleeping, they can even touch and travel around on them without detection; some are designed to live on or inside them even. That is about as up close as could be desired. Unique modifications can even work to get added niche "interaction" without being *perceived* as interaction: lightning bugs encourage juvenile Earthlings to capture them and provide entry into homes in a jar for good vantage point (no need to hide to escape destruction), ants in an "ant farm" will also have a good in the home view, honey bee hives nurtured by bee farmers are a great cover for field work on gardeners and farmers, and leeches can join the medical science community by offering wound healing opportunities as a nifty way to study living blood cells and other body defenses. And have you ever noticed how the dragonflies actually try to get our attention with their teasingly close in/dart away tactics? Very effective. ]
[Question] [ I've answered a few questions with this process but I wanted to see if I could bounce/refine this off the communities more biologically adept members. Basically, it goes like so: > > As a means of reproduction occurring between 2 completely different > species, I theorized that one specie could accomplish this if its > means of reproduction consisted of injecting a 'female' (of any species) with > retro-viral like structures that could fertilize an egg, pass on > traits and potentially alter the female's physiology to support the > pregnancy. > > > [technically I suppose the recipient doesn't even need be female] For the sake of simplicity, I will refer to these retro-viral like gametes as RVS's I know this is far fetched, simply because of the wild amount of things that need to go right: (FYI these aren't the post's questions) * How would these RVS's differentiate between an egg cell for fertilization vs a functional cell for mutation especially across the diverse spectrum of reproductive mechanics? * How would these RVS's know how to mutate cells to support the pregnancy * the amount of random chance needed for the inserted DNA not to break something important * the chances that the offspring could survive infancy * the effectiveness or severity of the immunological response **I postulate that one way this could work is that:** After picking a DNA containing host cell for fertilization, the RVS's release a chemical indicator telling the other RVS's to begin mutating other cells and/or enter an inert state (to be directed over the pregnancies term). The RVS's know what the RVS creature needs to mature and the host creature knows what its infant needs to mature. I assume the dormant RVS's could check for chemical indicators that the offspring's needs are being met (this sort of makes them more biologically like bacteria that produce retroviruses though). Because this is happening on the bacterial/viral level, I think the possibility exists that there is enough random genetic mutation happening such that if pregnancy fails and the host lives it could try a completely different approach. I expect the chances of this working to be slim. I expect that this would more likely result in the host dying during and after pregnancy. I would justify the evolutional advantage of this trait as a means for a creature to be able to rapidly adapt and evolve to environments. Why evolve its own intelligence and oxygen breathing lungs when it can steal yours. Or as a means of ecological subjugation. The said creature would likely target dominant lifeforms, ones that have advantageously adapted to an environment as they would have the necessary population levels to provide enough chances for successful offspring. **Anyways, my actual question which is semi opinionative, are there aspects I'm not considering? Are there factors that affect the plausibility more severely than I give them credit?** [Answer] **You describe [Wolbachia](https://en.wikipedia.org/wiki/Wolbachia).** > > These bacteria can infect many different types of organs, but are most > notable for the infections of the testes and ovaries of their hosts. > Wolbachia species are ubiquitous in mature eggs, but not mature sperm. > Only infected females, therefore, pass the infection on to their > offspring. Wolbachia bacteria maximize their spread by significantly > altering the reproductive capabilities of their hosts: > > > * They infect eggs (of many insect types). * The female that grows up from an infected egg will pass along the infection to her own progeny: vertical infection transmission. * If the egg is to become a male it dies; W wants females. * Some infected female hosts reproduce parthenogenetically because of the infection - no male needed. W wants females. * Huge overhaul of the body plan of the infected female is not necessary: finding food / evading predators / *making more eggs!* needs to stay intact. * If an adult male is infected with W it cannot reproduce - except with a female infected with W. Reproductive fitness of uninfected females is hampered. W wants females. * W infection can confer disease resistance and other superpowers to the host. [Answer] ## You do not need retroviral activity the fertilize a gametes The gamete (egg or sperm) has already moved from two copies of chromosomes to one copy. So you need a second copy of the chromosome. Better Plan is to use retrovirus against one gamete and then introduce this to the other gamete. Inerserting genetic information into a genome randomely is going to create problems (well with genetics on earth anyway. All bets are on alien system) First you can destroy important information second if you insert more than a small amount of information the chromosomes will not longer match up and the organism will just die. Finally. Really mixing genomes really doesn't work well in really life. this is mostly a science fiction thing. but you might want to look into the concept of instantaneous speciation through polyplody, though please avoid the sites that say this discredits evolution. Also <https://en.wikipedia.org/wiki/Bacterial_conjugation> the transfer of dna between bacteria might be of interest to you [Answer] The DNA and protein synthesis systems in a living cell are basically a chemical computer and storage medium. The only flaw I see is that the processing components are missing from a virus and it relies on its target cell having a certain set that it can hijack and use. As such, if you want this reproductive method to be completely universal it will need to be more like a bacterium than a virus, at least initially. That way it's guaranteed to have what it needs to run. Once established though it may well start creating viruses to hijack particular host cells and bend them to its will. With that caveat, there's no reason you couldn't have a (very large probably) DNA segment that codes for a process that will grab the host's DNA, analyze it, figure out how their reproductive system works, and hijack it to produce whatever kind of offspring it sees fit (or, you know, build a reproductive system that's more to its own liking if the host's isn't suitable.) The only issue is that DNA processing is, at a wild guess, probably no faster than a 4KHz computer. Think 1950s monstrosity reading punched paper tape. You can make it massively parallel, but that only helps with certain kinds of problems. As such, an interesting twist would be for it to analyze the host's metabolism first so it can build itself a mass of neurons to do its processing at higher speeds. Whether that mass of neurons would have sufficient programming to analyse the host nervous system (if any) and encourage it to feed and protect the spawn that are being created is up to you. Do note that something this complex is rather unlikely to arise in nature as inter-species competition makes finding sufficient resources to develop such a system exceedingly difficult. Most likely it would be the result of genetic experimentation in a lab somewhere that managed to escape into the wild, or a hyper-advanced species that has been doing genetic engineering for so long that they have merged it into their regular bodily functions. ]
[Question] [ In a steampunk world with airships and airplanes, but which lacks radio, how would different aircraft communicate, and how would they communicate with the ground? Would a form of semaphore, using flags controlled from within the aircraft be effective? What other methods would be possible? As a subpoint of that, what combination of message speed, and message complexity would be optimal? Would multiple systems, one for in-combat, quick messages and one for long battle plans be plausible? How could one effectively keep enemies from spying on messages? [Answer] ***You have a good few options, I think the realistic answer is a bit of everything.*** ## (a) Don't. I'm sure that a lack of communication between flying planes could be a great plot device. Maybe if two planes fly in a *really tight* formation, they can use cans & string. ## (b) Heliograph Use a Morse-type system where one can send messages by covering/uncovering a lamp or flashing sunlight In the other pilot's face with a mirror in some pattern. The lamp could be built into the plane with a lever in the cockpit to open/close the shutter, although this would be rather heavy. Probably a good idea to have a spring to make the shutter "closed by default". ## (c) Semaphore Have semaphore flags affixed to the outside of the plane, controllable with levers from the cockpit. Very heavy. Probably more practical on airships than on planes. May require the receiving pilot to use binoculars. Of course, none of these work outside line-of-sight, so: ## (d) Smoke signals e.g., the ones used by the war party chasing the war rig in *Mad Max: Fury Road*. Different colours = different messages. ## (e) Messengers Small, long-range aircraft. Give the pilot a piece of paper, hope he isn't shot down en-route. --- **Conclusion** * **Airships:** Semaphore system for communicating Intel with each other, the ground, and to pilots in good visibility; heliograph in poor visibility. * **Pilots:** heliograph (mirror or lamp) to talk back to the airships and to each other; * **Couriers:** for no-line-of-sight comms; they dock with a blimp and hand over the piece of paper or use one of the other systems to commune directly to pilots. But it's your novel; you can do whatever you want. *If you write this book please tell me* [Answer] It is important to remember that in the age of sail and into the early age of steam warships, captains of warships had a certain level of independence. They didn't need to be told every little maneuver or who to engage. There would also be a series of set battle plans (sweep left, engage at will, etc) that could be activated by a simple set of semaphore flags, a specific color sequence of flares, etc. Redundancy is key, signals in battle must be clear, concise, and unlikely to be mistaken for something else. The battle maneuvers are painstakingly rehearsed beforehand and designed to account for the chaos of battle, loss of the admiral's flagship, broken communications, etc. The concern with airship is how frequently they make landfall since captains can't just row across to another ship like they might in a naval fleet. If airships are perpetually aloft, then they will need to exchange more complex messages in a more secure manner, including the transfer of personnel and sensitive equipment. If they land every night or dock at a tower or something then face to face meetings can replace most communications. So for airships, there are numerous ways to ensure commo. 1. Semaphore flags run out on a long line along the airship. 2. Large colored panels of fabric stretched out across the inflated bladder. These could even be raised and lowered (or function like those changing billboards) to display real time information. 3. Signal flares, colored smoke, rockets, even colored powder bags dispersed into the wind, or dropped into the water or land below. 4. Flashing lights using a form of morse code. 5. Trained birds, homing in on specific markers on ships, could pass messages. 6. Balloons released with messages scooped up by planes equipped with wingtip hooks, then dropped into a large basket/funnel on another ship. 7. Loud air horns blasting audible code sequences or direct speech from one ship to another. 8. Rappelling from a higher ship to a lower one, possibly even using a glider to carry people or messages. The glider could land in a hanging net below another airship or into suspended nets on top. 9. Potentially even firing aerodynamic message containers from ship to ship, aiming for a catch funnel or net. 10. Pilots/passengers in planes could even use hand signals to each other to coordinate actions. Ultrahigh balloons or blimps could serve as line-of-sight extenders, relaying flashing codes or colors to the entire fleet. Obviously protecting codebooks would be paramount. Long messages with sensitive information would have to be encrypted in case they are intercepted or miss their target. [Answer] Here are three more options: **(d) [Pigeons](https://en.wikipedia.org/wiki/Homing_pigeon)** for one-way communication back to a ground base. **(e) [Railway-style mail-hooks](https://en.wikipedia.org/wiki/Mail_hook)**. Railways solved the problem 150 years ago of how to grab and drop written records without stopping the train. It's a close shave while flying, but barnstormers in biplanes can do it too. Not something to try with a Zeppelin. **(f) [Fulton/Skyhook lifting system](https://en.wikipedia.org/wiki/Fulton_surface-to-air_recovery_system)** for grabbing dispatches from the ground or lower-altitude craft. This is the coolest. Airplanes can do it easiest. Airships have a harder time simply because their fly-around time due to a misjudged wind is so much longer. Wire catching baskets on the airships will be popular, as will ground targets for dropped mailbags....and floating mailbags at sea. Most airships communicated with their ground crews using good old megaphones. [Answer] Morse or other code using mirrors or lamps is going to be the best for complex communication, but for simple messages there are other options. Dipping the wings or wagging the tail can be used for simple signals to other nearby aircraft. This would be important when trying to get a small group of planes to swing left or right or to dive. Setting off a flare or smoke canister works for longer range messages or communicating with more recipients. [Answer] For Zeppelins, it would most likely be Semaphore OR Morse code lamps, but these are line of sight solutions. These were used by Navies up to even WWII and most real world military Zeppelins were developed by Naval components and given names fitting Ocean Vessels. Most planes used some radio system as the Wireless Telegraph was invented before a military use of air planes. Most planes would have a co-pilot or crew member who's job was to relay messages from the flight deck with the pilot as the officer in charge of the whole plane (for a good demonstration of this, watch the film "Midway" which features the famous battle. Given that it was the first battle to rely on pure carrier tactics rather than battleship theory, it demonstrates the plane to carrier communications quite well. There are some segments that use actual recorded voices from real pilots in real combat in the real battle). Without radio, your airplane communications would be limited to line of sight and given the 10-15 minute limited operation of the planes, it would be better to issue orders to the flight crews and then let them execute them. There are no messaging systems that can overcome the speed and line of sight factors in the short time they have to remain operational. It's your story, but in this case, one of the earliest uses of military aviation is lost without the radio (recon) so you might want to redesign your fleet to be more Battleship theory than Carrier theory. [Answer] If we are assuming Zeppelins, airships or blimps, then we can assume analogous signaling as used by surface ships. Signal flags and lights would be very easy to adapt and have the great advantage that airships can be used as adjuncts to naval task forces since they would easily be able to communicate with each other. For fixed wing aircraft, this was actually an issue during WWI. Aircraft were generally too small to carry the bulky radio sets of the era, and of course vacuum tubes are not very keen on aerobatic manoeuvres, especially if things start crashing into them. Early aircraft also lacked compact reliable alternators or generators needed to power radios, so much more space and lifting power would have to be devoted to batteries if you were to carry a radio. Pilots instead operated by following plans developed and briefed on the ground, and inside a flight formation, wingmen generally watched their flight leaders and copied whatever manoeuvres they were doing, right up until a dogfight broke out. Pilots could communicate to each other through a system of rocking or "waggling" the wings to attract attention, then using hand signals to indicate things like the location of the enemy, which direction to go and so on. Ground troops could signal aircraft using coloured panels and markers to indicate their locations, preventing friendly fire attacks. Pilots could also be briefed on the location of enemy ground targets relative to known friendly locations, so looking for particular panel markers on the ground would indicate the point where they take a bearing and distance as they run in to the attack. And finally, although this seems like a cheat, airfields were often identified by painting the name of the airfield in large letters on the roofs of hangers. Given air navigation often consisted of following railway lines or canals , having the names of airfields painted on the roofs made locating the start and finish points much easier and more reliable. ]
[Question] [ > > Captain. 3 Klingons have beamed onto the ship. It is illogical, the laws of physics should not allow for teleportation. > > > So how do you board a spaceship that is able to defend itself without teleportation? I am aware of this question [How can a pirate board a spaceship without teleportation?](https://worldbuilding.stackexchange.com/questions/13554/how-can-a-pirate-board-a-spaceship-without-teleportation) but it only seems to answer what would happen boarding a defenseless ship. In this case the accepted answer involves space harpoons, which would likely be broken off by shots from the spaceship being boarded if it had any kind of defenses. So my question is would there be any way to board a spaceship given that: * Any process that is easily disrupted by enemy fire is out. * Any process that takes excessive time is out of the equation as it would likely provide time for your ship to be destroyed. [Answer] **Ramship.** [![piledriver ramship](https://i.stack.imgur.com/Bxkzy.jpg)](https://i.stack.imgur.com/Bxkzy.jpg) from <https://forum.keenswh.com/threads/comprehensive-weapons-thread.6617764/> 1. Ram spike into enemy ship. 2. Extend barbs so ships remain attached by spike. 3. Send space marines in through fenestrated spike. 4. Rinse. Repeat. This strategy is taken from the mating strategy of male bedbugs: [traumatic insemination](https://en.wikipedia.org/wiki/Traumatic_insemination). Bedbug penises are sharp needles and rather than scout out some purpose-developed route for sex, they inseminate the female (or another male!) by making a hole anyplace available and injecting the sperm. from <http://www.bedbugblog.ca/bed-bug-intercourse-traumatic-insemination/> [![traumatic insemination bedbug closeup](https://i.stack.imgur.com/ne1bP.jpg)](https://i.stack.imgur.com/ne1bP.jpg) <https://i.stack.imgur.com/gkeGF.jpg> --- **Lamprey** Lampreys are ancient fish with a feeding tactic well suited to a boarding party. The lamprey latches on to its victim with circles of teeth and hangs on. Once attached a rasping tongue carves a hole. [![lamprey jaws](https://i.stack.imgur.com/CzM24.jpg)](https://i.stack.imgur.com/CzM24.jpg) [![lamprey attached to fish](https://i.stack.imgur.com/a8wwG.jpg)](https://i.stack.imgur.com/a8wwG.jpg) The nice thing for the lamprey is that the tight seal made by the circle of teeth means that whatever flows out of the prey flows into the lamprey. For a boarding party with a lamprey ship a tight seal means a reasonable chance that atmosphere might be maintained inside the ship boarded despite the new hole in the bulkhead. [Answer] Adapt strategies used by terrestrial navies and police. Boarding a hostile ship is one of the most dangerous activities that individual sailors undertake. 1. Stealth - this is one of the strategies used by Somali pirates. Make contact with the target in the still of night, quietly place your armed crew around the ship, then round up the ships crew and lock them up. 2. Overwhelming firepower - the odds of survival are less bad if the ships crew surrenders than if they fight. 3. Shock - hit the ship with something hard enough to send the crew into physical shock (bombs), then board while the crew and/or ship is incapacitated. 4. Swarming - this is the strategy the Iranian navy claims to be practicing. Attack a ship with many smaller speed boats, expecting heavy losses, get in too close for them to bring weapons to bear, then board. The more people are involved with repelling boarders, the less they are attacking your swarm. [Answer] Given the extreme speeds of orbital and interplanetary travel, the biggest problem of all for boarding actions is the amount of kinetic energy that a boarding craft or even a single armoured Space Marine would deliver if they crash into the enemy ship. Ke=1/2Mv^2, and in Earth orbit "v" is just over 7\*kilometres\* per second. At that speed, [flecks of paint](http://www.dailymail.co.uk/sciencetech/article-3587882/What-happens-tiny-fleck-paint-hits-space-station-Tim-Peake-reveals-crack-ISS-window-debris-collides-craft.html) which peeled off boosters become astoundingly dangerous: [![enter image description here](https://i.stack.imgur.com/prvoM.jpg)](https://i.stack.imgur.com/prvoM.jpg) *Now imagine if this was an astronaut hitting the window....* A landing or boarding craft will be moving at high relative speeds in order to quickly close the gap, and will probably be making very hard "jinking" manoeuvres in an attempt to avoid missiles, kinetic energy rounds and laser fire. In any "realistic" scenario, this is a doomed quest, since real space warships may have megawatt to gigawatts of energy at their disposal and be capable of firing a Ravening Beam of Death (RBoD) laser capable of vapourizing steel, ceramic or carbon fibre in milliseconds at a range of *one light second*, just under the distance from the Earth to the Moon. In contrast, the New Horizons spaceship, one of the fastest ones ever launched, took 9 hours to go from the Earth to the Moon. That gives the RBoD 32400 seconds to slice the boarding craft into fine shavings. [![enter image description here](https://i.stack.imgur.com/jUfUQ.jpg)](https://i.stack.imgur.com/jUfUQ.jpg) *RBoD as outlined by [Luke Campbell](http://www.projectrho.com/public_html/rocket/spacegunconvent.php). If you are in orbit around the Moon when this thing fires in Earth orbit you are in real trouble....* Assuming you have handwaved the setting so no one has weapons of that calibre, then designing your boarding craft should be relatively straight forward. You need to accelerate and decelerate quickly, plus have the manoeuvrability to jink and avoid enemy fire, as well as crashing into exposed radiators and structures at 7Km/sec. The crew will be in a well armoured sphere in the core of the structure, and I picture it being in the centre of a ring of fuel and reaction mass tanks to provide protection from radiation and enemy fire. A ring of powerful rocket thrusters surround the equator to provide the manoeuvrability. In order to actually get aboard, there will be a series of grapples at the "front" to latch onto the enemy craft. One or more guns will be mounted in this area as well to deal with close in defence of the landing craft. The surprise is the "Corvus", an extendable tunnel with a large diameter cutting head to carve a hole in the enemy ship so the marines can enter. The Corvus is named after the ancient Roman boarding system, which essentially threw a gangplank onto the enemy ship and held it there with spikes so Roman Legionaries could rush across and board. [![enter image description here](https://i.stack.imgur.com/gIjJJ.jpg)](https://i.stack.imgur.com/gIjJJ.jpg) *Corvus mounted on a Roman warship* [![enter image description here](https://i.stack.imgur.com/igaaP.jpg)](https://i.stack.imgur.com/igaaP.jpg) *This image of a 60's era "space tug" gives you a bit of an idea. Note the boarding craft will be quite large in of itself* [![enter image description here](https://i.stack.imgur.com/WJqr0.jpg)](https://i.stack.imgur.com/WJqr0.jpg) *1980's era MOVERS OTV. If you wrap the fuel tanks around the central cylinder you get a more compact and better protected spaceship to visualize as the boarding spacecraft* So in real terms, boarding a non cooperative spacecraft isn't going to be a thing in any hot (shooting) war, and even with handwaves you will need a rather large spacecraft to carry out boarding missions (even recovery of damaged spaceships will require something on this size and scope). As always YMMV. [Answer] The distance between ships is going to be a big problem. So is the impact speed. Shuttling a boarding party over would take to long and so would cutting through the hull. Plus the cost of life support for the hours or even days of travel. Solution: **Boarding torpedoes full of murder bots.** Murder bots don't need life support and should not be sentient enough to care about how dangerous the action is. They also don't care about decompressive hull breaches. Making holds in the enemy ship could even be their focus. The torpedoes simply smash into the enemy ship, maybe plasma cut their way in and make murder happen. They have the added bonus of being completely expendable. [Answer] **real world examples with caveat**I would assume, it works similar to what current anti-pirate operations are doing, or the german submarine commerce raiders did before convoys and unrestricted warfare was a thing. You get in range, and try to intimidate using escalating means, like from machine-gun to recoilless rifle to whatever is the next in line, and destroy the morale of the target until he is unwilling to defend himself, force him to power down drive and weapons, then board them with a sciff if possible, or with a breaching pod if necessary. If just intimidating is not successful, you can hit it with something just powerful enough to disable critical systems like CIWS, Drive System, Life Support or Sensors to decrease the likelihood of surviving alone in the future if they don't surrender. Afterwards, the boarding is more or less a securing op rather than an actual boarding. But, with this you could argue that this isn't really boarding *during* combat, albeit technically the fight is not over until the target is secured. The only way I see combat boarding as a tactic in battle feasible it's by using non-people as boarding parties, like robots/androids, perhaps purpose built. Either use breaching pods to deliver them or just release a large cloud of them driven by Inertia, decelerating only precisely timed before impact, so their hardware still works, then beach the hull at wherever the target vessels structure is weakest. This would work very well when those boarding robots are simple and cheap. Let them disable the defences, then board them with people using sciffs [Answer] You actually have a lot of options: * Stealth boarding craft might be a good option. They can't shoot at you if they can't see you coming. * Hijacked shuttle might work too. If it is a carrier of some sort and is expecting some sort of shuttle craft or even fighters to board, they could be hijacked craft full of pirates. * Full scale assault could be a more exciting method as well. Say a single or even a few military ships are ambushed by a pirate squadron that simply keeps the major guns occupied with heavy fire while the boarding craft jump the gap. It really all depends on what the situation requires, and that was just a few ways I thought of off the top of my head. Maybe provide a few more details for a more precise answer. [Answer] You could have a small, fast, and armored strike craft with marines inside it launched from a capital ship, like a Cruiser or larger, and have the capital ship close distance to the target ship. If they target the boarding pods, then they get slammed by the capital ship, and if they get target the capital ship, then they get boarded. It's a no-win situation for the target if it engages, but if a ship boosted away, the boarding pods have to maneuver to hit their target, and this would give the target ship's point-defence more time to take out the boarding pods. The target ship could also use its FTL (depending on the universe) to escape, unless it is disabled or something is blocking it. For the attacker, just using a custom ship with a ton of armor on the hull could slam into the target, but at the risk of the enemy boarding and taking your ship. [Answer] Boarding can only be successful on an unaware or unresisting ship. There are just too many ways to defend against boarders (including maneuvering). After that boarding methods depend on whether you want the crew/passengers of the target vesicle alive. If not, go in with full suits and use breacher rounds. If you want to take them alive, you have to bring an airlock with you. [Answer] There is always stealth. You are not using the mark one eyeball to do detecting in space. Takes to long to enter data. Therefore you must be using some sort of electronic detection system. Any electronic detecting system can be spoofed. The smaller the ship the better. Radar jamming system and optical jamming systems are already being used. All ships have have a way of entering them built into them these are the fastest way to enter any ship. The tricky part is forcing the ship you want to board into your boarding party. Whom you have placed before you drive the ship you wish into them. They can not use any energy until they are ready to actively board because that energy can be detected. Some form of netting that can be placed in space and left there for a day or longer this holds your boarding party and brings them into contact with the ship to be boarded. Once they are in contact with the ship all they have to do is enter the ship with breaching charges, if you only want the ship and not its crew, if you want the crew blow the ship apart then retrieve the crew as they enter life pods. This means that you must use your ship or ships in such a way as to force the ship to be boarded to go were you want it to go, not easy but doable. They either chase you or you chase them into the net. The net has to be able to go from a relative dead stop to the ships speed with contact with the ship. The boarding party has to be able to reach the ships speed but need not do so as quickly if the net can stretch. (This is they way aircraft land on carriers at sea. It is also they way air drops are made from air craft today.) Is such a material around today I don't know. The boarders must be packaged for the forces they will encounter but we air drop the most delicate equipment today so it is possible. There you have a boarding plan with about a 99.9%+ fail rate. [Answer] Zap the enemy ship's engines with powerful lasers. The only real defense against lasers is not being on their path. You can only see them when they hit your sensors because physics is a cruel mistress. Once a ship has lost engines during interplanetary travel, **they will ask to be boarded. With a white flag.** The reason being that their alternatives are: * Give up and keep trajectory, which causes them to either impact against their destination or flyby around it. In both cases they would do so at bat out of hell speeds. For example, supposing they are headed towards Earth, they will be passing by eleven point two kilometers per second relative to the planet at the slowest. Coming from outside the solar system, the slowest speed of a crash or flyby would be [closer to eighteen kilometers per second](https://space.stackexchange.com/a/3613/16652). Flybies are more probable, but any rescue missions from then on will be prohibitively expensive. * Pray that help comes before you can blow up whatever is left of them. * Crew suicide. ]
[Question] [ In fantasy literature wyvern’s often have their habitat set as extreme mountains. Sometimes even depicted as needing to drop from a height in order to take off. Evolutionarily speaking this does not make sense to me. It seems to me the calorie requirements of a flying creature large enough to carry people would be quite high and not supportable in standard mountain biome. Also, if such a creature evolved naturally it is more likely that it could take off on its own without the drop. What are the environmental requirements/considerations for a wyvern’s habitat from an evolutionary perspective? [Answer] Just as a start, and other answers may not have to do this, let's *really* assert the fact that a wyvern is a large reptile. Disregarding any of its advantages with flight or hunting preferences, we have to establish that it's somewhere **warm & sunny.** That's right, these big guys are ectotherms like any other lizard and need to bask in order to regulate their body temperature. They could even spread their wings to radiate excess heat or fold them in to stay warm (I think half a dozen basking wyverns on a beach makes for a good visual). For ideas on how active your wyverns can be, you can look at the [Komodo dragon](https://en.wikipedia.org/wiki/Komodo_dragon) or [Marine iguana](https://en.wikipedia.org/wiki/Marine_iguana) of the Galapagos. Time spent swimming or flying means a big decrease in body temperature and high energy consumption, so it's doubtful that swimming and flying are things that your wyvern can do for a very long period. Of course this is a narrow definition of behavior, and not the only one seen in reptilian evolution, but anything you choose or want in terms of behavior and habitat will hinge on your reptile's ability to regulate its body temperature and get enough energy for activity for some time during the day. [Answer] It is not hard to find mountains immediately adjacent to grasslands and herds of large grazers / browsers. Below see Grand Teton and Kilmanjaro (Kilmanjaro has the elephants!). I can imagine wyverns up on those mountains. [![enter image description here](https://i.stack.imgur.com/9iOsS.jpg)](https://i.stack.imgur.com/9iOsS.jpg) [![enter image description here](https://i.stack.imgur.com/o2czE.jpg)](https://i.stack.imgur.com/o2czE.jpg) If you are big, powerful and mobile you do not need to eat right where you live. You can commute. I am thinking of whales which live and breed up at the top of the water (because they need to breathe!) but dive down and hunt in the abyss, a mile or more below. The wyverns could live up on the mountains and then glide out over the grasslands to hunt. I think a mountain would be fine vantage point from which to scout out likely buffalo or elephants to eat. Benefits of mountains: no bugs, no nest predators, great visibility. Sweet updrafts for gliding. Less humidity = less wing fungus. Delicious snow to eat. Re: mountain too cold for lizards - even cold blooded animals are not necessarily endothermic. Both tuna and great white sharks have (different) methods to warm their muscles with metabolic activity. I have read theories that dinosaurs may have had similar methods. [Answer] I'm not familiar with wyverns in fantasy literature, but in mythology, the wyvern is a sea dragon - two legs instead of four, and a tail adapted to swimming. I'm inclined to think that a creature like that would have similar calorie requirements to other amphibious creatures of similar mass. Is this just curiosity or are you writing a story? If the latter, then you can make up a few rules of your own and make your wyvern distinct. [Answer] First, let's get one thing out of the way. A wyvern is *NOT* necessarily reptilian. You can, taxonomically, make a wyvern whatever you want. With this in mind, I will be writing two scenarios. **Scenario 1** In this scenario, wyverns are mammalian, venomous creatures, sort of like an oversized cross between bats and [pangolins](http://naankuse.com/wp-content/uploads/2015/09/pangolin-slider.jpg). The wyvern may get its venom from snakes, giant bugs, or crustaceans it eats, or simply manufacture its own venom like *[Blarina brevicauda](https://en.wikipedia.org/wiki/Northern_short-tailed_shrew)*. In this case, it would likely live in alpine climates (Most likely the actual Alps or the Himalayas)and feed on mountain goats or yaks. **Scenario 2** In our second scenario, wyverns are reptilian, similar to pterosaurs, with venom glands like the spitting cobra, and serrated teeth like a monitor lizard. These wyverns would likely dwell on volcanic islands, diving for large fish, or in rainforests, luring megafauna to its territory by shaking the canopy as it flies by. [Answer] The key points that need to be taken into account are the fact that it's a large predator and that it flies. You need to have an environment with prey either large or plentiful enough to feed it. If you make it warm-blooded it will have a pretty high energy requirement and it will hunt frequently, this will probably necessitate that it hunt on the ocean rather than on land (depending on how large you make it). Cold-blooded it will need perches to sun itself but can get away with not eating that often (so it lends itself better to a standard fantasy environment). If you want a creature that soars/glides rather than flaps (think of eagles/hawks as opposed to bats) it will be a fairly delicate creature that hunts relatively meek and delicate prey. It also can't hunt on the open ocean because there are no thermals for it to glide on so it would be a coastal predator at most (if it hunts on water). If you want a flapper then it will be a heavy bulky creature that can probably take on stronger prey but also will have a consequently higher energy requirement. So depending on which combination of things you put in you'll need to incorporate certain environmental conditions. [Answer] I think of a wyvern as a lesser kind of fantasy reptile. Smaller, less powerful, and without the fiery-breath element. Perhaps an opportunistic scavenger, as opposed to the big old regular dragons at the top of the food chain. Maybe they'd pick over the scraps of dragons' kills and piggyback off the bigger guys' caloric expenditure, rather than waste their own energy in hunting and killing prey themselves. A 'lesser wyrm' kind of reputation, as a hyena might be to a lion, or a vulture to an eagle. If they relied mainly on bigger dragons to get their food for them, then they'd probably live wherever dragons live – which could be anywhere you like. But realistically, they'd be the most successful around arid brush and savannah. I agree that a hot habitat would make the most sense for a reptile. But bear in mind that higher altitudes will be significantly colder, so a large reptile that relies on its bodyheat to get airborne and stay there may nest around warmer foothills, crags and outcrops. (Rather than high dramatic peaks). Unless of course it's a fire-breather itself, in which case it could warm itself at will and live wherever you'd like. To answer your question, maybe ask yourself what it's likely to eat. A wyvern could evolve for many different environments, which would dictate the size that it needs to be. Say a tiny one that preys on frogs in swampland, or pack-hunting wyverns that dive on huge shoals of fish off the coast. The environment would also dictate their shape and colour, to camouflage them from prey (or predators). Hope this helps! [Answer] Argentavis and pterosaurs seem to provide strong precedent for this big bird. Argentavis was a scavenger that scouted for carcasses across savannas. It didn't have the easiest time getting into the air, compared to the v-toll of a pigeon. Pterosaurs are believed to have hunted smaller airbornes and fish, as well as some land creatures, don't forget that they had teeth. You need open spaces for this to work and a lack of stealthy, threatening creatures. Breathing fire to clear forests or a technique for scaring prey out of cover would be invaluable. The ability to climb or perch would be pretty neat too, helping them survive in diverse climates. Seaside habitats would help generate the kinds of winds a creature like this would desire, occasionally creating convenient convection currents. ]
[Question] [ Since gamma radiation consists of photons, just like visible light does, albeit on a different frequency, isn't there a plausible way that in, say, 200 years into the future, we could harness the power of Gamma radiation? If yes, what would the hypothetical methods be, granted the same amount and proportion of natural resources that are present as on Earth? If plausible please use science where you can. If this is physically impossible, please back that up as well. [Answer] # Yes, it's been tried. [Hashizume et al.](https://www.cambridge.org/core/journals/mrs-online-proceedings-library-archive/article/direct-energy-conversion-from-gamma-ray-to-electricity-using-silicon-semiconductor-cells/AD86142E057DC2D41E77AD7E28DD10A7) attempted to use semiconductors (variants of which are also used in normal solar cells) which were subjected to gamma radiation from a radioactive isotope of cobalt. They generated up to 0.2 Watts/meter² — certainly not a lot. The energy conversion efficiency? 1%. Furthmore, the cells were, as the authors put it, "unstable". However, none of this means that this method won't work — it just won't be very effective in the near future. For comparison, solar cells can generate energy [at about 25% efficiency](http://spectrum.ieee.org/energywise/energy/renewables/efficiency-of-solar-cells-continues-to-climb), and [solar irradiance](https://en.wikipedia.org/wiki/Solar_irradiance) is orders of magnitude higher than what was generated by these gamma-ray semiconductors (1361 Watts/meter²). These devices won't be widespread any time soon. I *suppose* you could try to use something like a [radioisotope thermoelectric generator](https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator), which produces heat via radioactive decay and then converts that heat into energy. However . . . * These devices avoid gamma radiation because it is too energetic. * You'd need materials more radioactive than normal to generate the required gamma rays. * Nuclear power is not wholly popular as is. You'd have to convince a lot of people that the whole setup is safe in order to deploy it on a large scale. Jan Dvorak [suggested](https://worldbuilding.stackexchange.com/questions/80602/can-gamma-radiation-be-used-to-generate-electricity#comment234448_80605) essentially surrounding a reactor with electricity-generating semiconductor cells sensitive to gamma rays, which would both generate electricity and perhaps provide some radiation shielding. It's an interesting thought, and could certainly work. I do wonder what the irradiation would be at different points within the reactor chamber. [Answer] **Yes** In modern [fission reactors](https://en.wikipedia.org/wiki/Nuclear_reactor) a small amount of the energy released is Gamma radiation. It is captured by the reactor shielding and contributes to the overall heating of the system. If you had a highly active gamma source the same could be done to heat a large piece of shielding. That heat, in turn, could drive a [Rankine Cycle](https://en.wikipedia.org/wiki/Rankine_cycle) (like modern reactors) or [Sterling Engine](https://en.wikipedia.org/wiki/Stirling_engine). For efficiencies much better than a panel. For comparison, a Rankine can have efficiency in excess of 40% percent and Sterling engines around 20%, though I seem to recall seeing %50 somewhere. ]
[Question] [ Is it possible to create some "thing", for lack of better words, that is a kind of information, like a joke or a pop-song that can spread across people and make them become depressed and suicidal? If this is possible? What properties must it have in order for it spread across different people and cause them to be so depressed that they commit suicide? [Answer] This is going to be very controversial but some people would argue some forms religion would qualify, suicide cults keep popping up, the depression aspect is even more common. [Answer] Ultimately, what we're talking about is creating an infectious **thought** that causes people to value death over life. So there are really just two ways to do this: 1. Increase the value of death, suicide, or depression-inducing behaviours. 2. Decrease the value of life. ## Option One Both of these are real and serious dangers, and things we have observed in the real world already, as others have already observed. The modern concept of *jihad* is not a natural aspect of most Islamic theologies in its commonly understood form, but is a *possible extension of some of them*. In this specific case it is essentially accomplished by affirming the idea that *only a glorious death in service to God can ensure eternal life*. This isn't necessarily a far cry from some Norse, Spartan or Japanese concepts of a 'glorious' or 'honourable' death. On the flip side there are subcultures like those people refer to as *emo* or *goth*, which glorify depressive behaviours over positive ones. If you're able to affirm the worth of such behaviours to the point where they are more overwhelming than those which encourage people, then you gradually create an oppressive culture which will increase the risk of suicide. Thinking back to the memetic property, this would probably take the form of a story, a poem, a song, a video or popular saying which reinforces ideas of death or depressive-type behaviour being a good thing. ## Option Two Make life worth less. It's a tragedy and a travesty that as Westerners we really don't have to think too hard about this one - what are the main things which people draw personal value from? Therefore to undermine people's self-worth and increase the relative perceived value of death, the following would be fairly effective: * Undermine the integrity of **family and marriage**, either specifically or generally. If people can't trust their own families to stay together and can't trust another person enough to commit themselves to them, then their perceived self-worth falls. * Undermine their sense of **identity**. Identity is a person's sense of ongoing self-sameness. If somebody does not have a strong sense of being the same person from one day to another, and has people affirming that they are significantly different from who they *think* they are, then this increases depressive thoughts. * Undermine the basic value of **life**. Normalise death. Encourage death as a good and positive and normal thing for old people, adults and children alike, especially for those with less perceived worth. Too old? Too foreign? Too disabled? Too young? Too helpless? There are a thousand categories you can choose. But undermining the basic sanctity of human life at any age inevitably ties life to *worthiness*. And if **all** people are not basically *worthy* to live, then everybody is left asking themselves that same depressing question: Why am I alive? * Undermine their sense of **community**: people are basically social animals. If you drive people into singleness and loneliness, then they will struggle to sustain their own happiness, and miss out on all kinds of affirmation from other people. If people don't form strong bonds with other people or don't value forming strong bonds with others, then they will probably become depressive unless there is another particularly strong sense of meaning in their worldview. * Undermine any sense of **objective morality**, i.e. divinity. Objective morality depends on an over-arching schema which gives things meaning from the outside. In most cultures **God** is the one who gives all things meaning, and so people draw meaning and self-worth from him. Undermining this concept and removing objective morality and objective worth can rapidly deteriorate somebody who has learned to rely on this for meaning. * Undermine their sense of **reality**, and invest their identity or self-worth somewhere else. **[This happens already!](http://edition.cnn.com/2015/01/19/world/taiwan-gamer-death/)** If a person invests too much of themselves in an alter-ego to the degree that they neglect their physical self, then they can die of self-neglect. * Create an **unrealistic standard** of 'worthiness' in life. If you can create a wonderful and noble and glorious standard of life to which everybody should always attain, and reinforce that this is the most important thing everybody should do, then that becomes depressive. It's the most common reason people quit Facebook - because of this perception that *everybody is happier than me*. If the basic standard required to make life worthwhile is higher than most people's actual or even possible standard of life, that creates a depressive setting for the majority. **Disclaimer: I personally disagree strongly and passionately with all of the above ideas, and only present them because they are true answers to the stated question of increasing depression and suicide among people.** ## Application In a worldbuilding setting, a central memetic agent could hit all these different marks, and to do so in much more overt ways than western cultures do today, whilst still being subtle enough that it's not obvious to the consumers that this is their objective. It would be really easy to create a story which is simple, believable and larger-than-life, because it really isn't too much different from the world many of us already live in! Isn't that simultaneously sad and encouraging for you as you consider creating your story? [Answer] Killing meme is quite popular among the culture. There was a movie [Kovak's Box](http://www.imdb.com/title/tt0455584/). In the lore of the movie majority of human population has implants, that are triggered by [Gloomy Sunday song](https://www.youtube.com/watch?v=KUCyjDOlnPU). And this implants gives their hosts so drastic depression, so they performs suicide. There is a [Lullaby novel by Palahniuk](https://en.wikipedia.org/wiki/Lullaby_(Palahniuk_novel)) about a book with children lullaby (`sad song about animals going to sleep`) that gently killed people. I think dangerous Memetic Viruses a real. Just take a look at youtube: There are a lot of popular [fails channels](https://www.youtube.com/results?search_query=fails) on youtube. 80% of fails are attempts to perform some sort of stunts, and make a video to upload on youtube too, but instead of it, performers fail and get injuries. Maybe fail videos are memetic virus? They are spreading via youtube and sharing links to videos, they are replicated by people trying to perform stunts and upload it to youtube, and they actually harm and sometimes even kill people. I think this list can give you inspiration. [Answer] It was done back in WWII, or at least [Monty Python](https://www.youtube.com/watch?v=WwbnvkMRPKM)'s history lessons says it was done. There's nothing that quite prevents this idea from becoming a reality, but there's also not any good reason to believe it can happen. If you think about it, such a body of information would be a major glaring weakness in all of humankind. It would have to be burred deep into our genome, there for hundreds of thousands of years. Such a weakness could be quickly exploited, so I would presume that there would be at least one species that exploits it. Three possible paths: * If we were "seeded" on this planet by aliens, they may have left a kill switch in our genome, in case we got out of hand. * It could be that we find a "problem" which causes the human brain to enter an endless loop similar to what we can do with computers with the halting problem. The Neil Stephenson book *Snow Crash* explores something along these lines. * Truth is stranger than fiction. While not exactly a joke, [this fungus](https://www.youtube.com/watch?v=XuKjBIBBAL8) infects an ant's brain, giving it suicidal urges. The real "memetic virus" may be more along these lines [Answer] Alright, the problem with a "depression meme" is that it's self-defeating, and competing with other memes for brainspace. So, you've got a meme that gives people instant, severe depression. It's going to destroy all its transmission vectors. If the person who absorbs the meme is depressed enough to commit suicide, they can no longer transmit the meme. Even if they aren't depressed enough to commit suicide, they're still probably depressed enough that they won't feel like making posts on social media, or going out and talking to people, or otherwise spreading the meme. Successful, continual memes have some way to elicit people to spread them. It's like a very severe plague, but it can't spread even from living carriers. Next, this meme needs to compete with other memes for brainspace. Every moment spent thinking about doge images is one moment that isn't being used to think about this depression meme. And the other memes are going to encourage the hosts to seek out, or create more variants of those memes, thus causing them to gain more brainspace. The "depression meme" is going to make people depressed and then they don't really have motivation to do much. [Answer] Many years later, I think I found something approaching the answer to the question in real life: the Among Us memes It has all the pre-requisites to be a deadly memetic virus: * it spreads, with great virality * it impairs the hosts' functions (causing some people to enter a sort of hysteria when seeing certain images or hearing certain trigger words) It is not yet deadly in the sense that it has yet to cause any direct casualties, but it's not inconceivable that something similar to the Among Us meme can become deadly to individual hosts or cause societies to undergo systematic collapse ]
[Question] [ Imagine a world that works mostly like our own: it's built of atoms and quantum particles, there's gravity and conservation of energy, etc. Perhaps the physical laws aren't *exactly* the same as our universe, for sci-fi purposes, but overall the world looks, feels, and operates just like our own--with one, massive exception. In this world, there is a Handwavium of sorts that just doesn't play by the rules. It isn't made of recognizable particles, doesn't follow conservation of energy or momentum, and resists all attempts of scientific investigation. It's widely believed to follow its own set of laws completely separate from ordinary matter, but no one has been able to figure them out. Maybe it's made of a new class of particles; maybe it's some completely new kind of "stuff" unlike anything in our universe. Nobody knows for certain. The problem is that this Handwavium isn't floating out in space or in some sort of shadow dimension: it's a very common substance in this world and forms large portions of the ground. It's visible, heavy, touchable, and behaves a lot like rock most of the time (except for when the story needs it to do something more interesting, of course). At least, that's what I want it to be like, but I'm starting to feel that this is logically inconsistent. If my substance doesn't obey quantum mechanics, then how can it interact with photons to be visible, or electrons to be tangible? If I disregard real world physics entirely, I don't think I can satisfactorily justify why it superficially behaves so much like ordinary matter, especially since the rest of the universe is supposed to be relatively hard-ish sci-fi. So, my thinking goes, even if it isn't made of electrons and quarks and gluons and whatnot, maybe it can superficially *act* enough like them to explain its appearance. For example, it doesn't have electrons, but some of its structure is negatively charged, and is "electron-like" enough to repel ordinary electrons and become solid. In programming terms, I want it to "implement the physics interface" while being completely different under the hood. # Preliminary sub-question (probably too opinion-based): is this a plausible explanation for my Handwavium's properties? I myself have [drilled users here in the past](https://worldbuilding.stackexchange.com/questions/51696/is-this-way-of-messing-with-physics-possible#comment144306_51696) for asking about the "plausibility" of systems that knowingly invoke alternate laws of physics, but remember, I'm staying rooted in real-world physics here, and then tacking on something "other". **Based on the real physics that I'm mostly sticking to, is it possible to postulate anything about whether not nor my idea makes sense?** If not, move along, that is not the main thing I'm here to ask. # Main question (assuming the first part is positive or unanswerable): what is the minimum behavior my Handwavium has to express in order to "act like" ordinary matter? Extrapolating on the electron/tangibility example I gave earlier, what would this substance have to do in order to: * Be solid to the touch. Negative charge seems like the answer. * Be visible to the human eye. Other radiation doesn't matter. * Have mass and be affected (perhaps inconsistently) by gravity. This is probably unanswerable considering that we lack a theory of quantum gravity. * Be movable by force (transfer kinetic energy). Like with gravity, it's a bit lazy in this regard, seems to follow intuitive mechanics but isn't consistent with the amount of force needed to move it. * Have temperature. * Optional challenge question: give it a taste and smell, explaining how it triggers the receptors and what it tastes and smells like. BUT: * No conservation of energy/momentum. * None of Newton's laws: + It can start moving with no force acting upon it. + Acceleration is unpredictable. + A force can be exerted with no opposing force. * None of the laws of thermodynamics: + Heat can flow from cold to hot. + Entropy can decrease without expending energy -- MAYBE. I know this is probably the most fundamental law I'm breaking here and it's not a big deal if this can't be accommodated. I haven't thought about relativity, could go either way. All of this applies only to the Handwavium itself, not to regular objects interacting with it. So for example, regarding Newton's law, if you punch a block of it with 20N of force you will have 20N of force applied back to your hand, but if it reaches out and punches you with 20N equivalent of "force", there's no saying what the force applied back on it will be, if any. Hopefully this makes sense. If not, please explain why. Note: I really don't know how to tag this, I refrained from using "science-based" or "reality-check" but I'm not sure if there's something more appropriate. Thanks. [Answer] What you describe is remarkably similar to the traditional philosophical stance of dualism. Dualists believe there are two fundamental substances in the world: matter and mind (they get different names, but I find these are the most popular two). Matter follows the laws of physics, and mind does not. Mind typically has something called "freewill," though it's not very well defined. The important part is that mind does not follow the laws of physics. This is actually a well documented philosophical approach dating back *literally* thousands of years (Plato talked about it, for instance), so there's lots of work out there to suggest you're not crazy for trying to make a story out of it! Now for the fun part: science doesn't do what you think it does. Most of us in the Western world are brought up believing that science tells us what reality is, but that's never what science was supposed to do. The best scientists know it, but we've convinced a huge portion of the population that science seeks what philosophers would call *ontological truths*. Ontology is the philosophy of reality. It answers the question "what is 'real?'" If I say "electrons exist," that is properly thought of as an ontological statement about reality. Science is actually a branch of *epistomology*, which is the study of knowledge. Science is concerned with what we can *know*, not necessarily what is real. A lot of times you can get away with muddling the two, but when exploring the topic you are exploring, it's very helpful to recognize how distinct they are. Diving a little further, science is a branch of empiricism, which explores what we can know through empirical measurements -- what our senses tell us. When scientists talk about electrons and protons and quantum mechanics, what they're actually talking about is models. They say that if you think of the world in terms of these electrons and protons, you can very effectively predict what is going to happen in the future. They back this up with empirical evidence showing that, every time they used these models to predict the future, the results were just as they predicted! Of course, talking about things that can be "modeled as electrons" is a bit verbose, so in science we change the meaning of some words. When science says "there are electrons," what they actually mean is "it appears that you can model reality as though it has electrons, and you can predict what will happen." The former is just shorter, and we assume that you knew what we meant. So when your scientists face this handwavium, they may notice that, in some ways, it behaves as though it is made up of electrons and protons. You can model your handwavium as electrons and protons and make good predictions. However, some of the predictions fall short. For example, electrons and protons are not permitted to disobey the conservation of energy. So rather quickly the scientists will realize that it isn't made of electrons or protons. However, they will soon realize that you *can* model it as though it has an electric charge. They don't know where the charge is coming from, but they know that if you pretend this blob of handwavium has a charge of 3 columbs, it does a great job of predicting what will happen next! Don't try to make your handwavium "act like ordinary matter." Instead, give it the particular properties of ordinary matter that you find important, such as the ability to absorb or scatter photons. You can go as deep as you please. You can try to have your handwavium interact "properly" at the quantum mechanical level, or you can just assume it operates on the classical mechanics scale (which would mean that any attempt to interact quantumly with handwavium would automatically collapse the waveform before the interaction occurred). Your handwavium can break any law of physics you please. Remember, they're artificial laws, invented by humans to characterize the world around us. However, do realize that the humans in your world will adapt. The more the physics of handwavium is important to life on your planet, the more their concept of physics will account for the behaviors of handwavium. Perhaps your scientists will find [Aristotle's theory of motion](http://www.iep.utm.edu/aris-mot/) more applicable in their universe because it captures the oddness of handwavium better. As an example, I'd offer one of my favorite theories from the Marvel universe on Thor's hammer, Mjolnir. I've since found this theory disproved, but I like it so much better than the official stance that I keep it around anyways. It concerns why Thor is the only one who can lift Mjolnir. The theory is that the hammer isn't actually heavy, it's merely stubborn. The reason Thor can lift it is because he's the only one who is more stubborn than it is! How's that for handwavium? [Answer] Oxidation Your abnormal matter could have a surface effect that makes normal matter stick to it, or the surface turns into normal matter the way many real-world material oxidize at the surface. [Answer] What you're seeing is actually a 3-dimensional "shadow" of the true substance - the actual bulk of the material is outside of this dimension, allowing for changes in momentum/mass without (to outward appearance) the application of external forces. [Answer] These particles could bind to normal atoms somehow and be mixed in with normal materials. For example, you could have rock with these particles mixed in it, but these particles have infinite energy or something so they can put energy into the atoms. This would let them start moving with no outside force other than these magic infinite energy particles. Maybe they could also absorb infinite energy too, so they could randomly cool stuff. The particles could move around atoms or change them so they wouldn't have gravity. Basically, it is normal matter but it doesnt act like it all the time. [Answer] Nanobots could all of the above, up to certain limit, undetectable when there are no electron microscopes. Movement can be done using invisibly thin tendrils attached to the surrounding environment. Thermodynamics "violations" are doable with ability to store/release vast amounts of heat, or invisibly exchanging it with the environment. ]
[Question] [ I'm designing a world similar to Earth (liquid water, temperate climate, there is an atmosphere, oxygen and complex life everywhere). The only big difference is that there is a giant (not glowing!) moon with an impossible orbit, and its shadow is always on the same area on the ground. So I basically have an area with good life conditions, but no sunlight (We can assume that some river will cross the dark area and that wind will bring oxygen in it from illuminated areas). I'm aware that such an orbit is not realistic, let's ignore this point. What would life (plants, animals) look like and evolve? Could light be used as another tool by evolution? I though about mushrooms, and I looked for similar conditions that could exist in real life (caves?), but I didn't find anything that could be interesting for a story. [Answer] **Your answer lies in the deep places of Earth** because those are the exact same conditions you've described. Life in these areas have developed sensitive chemical sensors or very sensitive eyes (or no eyes) to locate food. Often they have no coloring because there's no use for it in absolute darkness. In the darkness, creatures sometimes form symbiotic relationships with bacteria. [Tube worms rely on bacteria in their gut](http://www.expeditions.udel.edu/extreme08/creature/tubeworms/) to transform the hydrogen sulfide in the water into something the tube worm can use for food. Others feed on detritus that falls from higher up in the the water column. ## **Terrestrial Life** [![Amphipod](https://i.stack.imgur.com/ZdoeW.jpg)](https://i.stack.imgur.com/ZdoeW.jpg) [![Cave Shrimp](https://i.stack.imgur.com/KJh7Q.jpg)](https://i.stack.imgur.com/KJh7Q.jpg) ## **Aquatic Life** [![Hatchetfish](https://i.stack.imgur.com/67ztc.jpg)](https://i.stack.imgur.com/67ztc.jpg) [![Anglerfish](https://i.stack.imgur.com/y8gYm.jpg)](https://i.stack.imgur.com/y8gYm.jpg) Just don't go too deep. [![Balrog](https://i.stack.imgur.com/N0r8y.gif)](https://i.stack.imgur.com/N0r8y.gif) [Answer] **Look deep down below the water** the life would be mostly anaerobic (not breathing oxygen, not producing oxygen.) and on cell level. For complex life you need more energy = light Add light, otherwise say good bye to complex animals :) [Answer] The problem with this whole scenario is that you need a source of energy for life. On earth that is almost always the sun, the only exception being certain geothermal vents. Even the deep oceans get food coming down from above which originally used sunlight. In other words there would be nothing living in this area, it would be a dead zone. The only way to correct that is to have stuff coming into the zone - possibly using geothermal vents as suggested in the other answers - or possibly being brought in through wind or water. For example if you had a massive river flowing into the dead zone then it would sweep life in with it. Eyeless scavengers could then live alongside the river grabbing anything edible that comes floating down. [Answer] I would start looking first at [hydrothermal vents](https://www.boundless.com/microbiology/textbooks/boundless-microbiology-textbook/microbial-ecology-16/microbial-symbioses-196/hydrothermal-vent-microbial-ecosystems-989-5466/) in the ocean. They feed microorganisms in colonies creating a 'bacterial mat' which in turn attract "Snails, shrimp crabs, tube worms, and fish feed on the bacterial mat". These in turn draw larger animals like octopus and squid. On top of that. The there will still be energy being applied to nearby ecosystems from the sun and light as as such there will be other things that could live there. Just not 'plants'. Now there is a problem with your imagined situation. Physics won't allow things to work just how you've said. A moon has to travel around (orbit) the planet, not it could be in a geostationary orbit which would keep it exactly over the same spot on the planet, however, it's shadow would move around. It would prevent direct sunlight from ever reaching a certain area, but would not prevent all light forever. Any moon planet at an inside orbit between the sun and the planet itself, would orbit the sun at a faster speed and thus only block the planet for 'short' periods of time. If they were close enough to have a very similar orbit they would interfere with each other. [Answer] Actually this already does exist in deep waters. Near the bottom of the ocean (specifically, below the [Photic zone [sunlight zone]](https://en.wikipedia.org/wiki/Photic_zone)) there are creatures that survive with effectively no sunlight at all. They've adapted to either create their own light, or use other methods to detect their prey and eat. How would they look? > > [![The barreleye](https://i.stack.imgur.com/f6Koa.jpg)](https://i.stack.imgur.com/f6Koa.jpg) > > > Source: <http://www.mbari.org/news/news_releases/2009/barreleye/barreleye.html> > > > [![Rainbow Jellyfish](https://i.stack.imgur.com/2sh5E.jpg)](https://i.stack.imgur.com/2sh5E.jpg) > > > Source: <http://news.nationalgeographic.com/news/2009/03/090317-new-rainbow-jellyfish-picture.html> > > > [![Abraliopsis Squid](https://i.stack.imgur.com/ASbLV.jpg)](https://i.stack.imgur.com/ASbLV.jpg) > > > <http://www.wired.com/2011/01/bioluminescent-sea-creatures/> > > > [Answer] According to [origins of life](https://en.wikipedia.org/wiki/Abiogenesis), life originated without need of light, and only much later photosynthesis evolved. So yes, **life could, and did, evolved without light**. Plants and higher life forms would have hard time to evolve though, because without light energy there is no photosynthesis. Without light, all your life would likely be bacteria processing chemical energy resources like volcanic vents. [Answer] I think you should explain how the moon came to a fixed orbit. Was it always like that, or id it halt due to a catastrophe of cosmic proportions? If it's the first case, then you could use a lot of the answers already provided to create a basis for the creatures living there. But if it's the second case, you can say that the complex, even sentient creatures already living there have evolved and adapted to the new circumstances, even if it was over the course of centuries. Also, you need to specify how large this moon is. Let's say that your world is the size of Earth and this moon is the size of Australia. Even if it was always on the sky, the area it hovers over would not be completely dark, as you could see light at the edge of the horizon. Perhaps the creatures inhabiting that area can adapt to live in a world with less light. [Answer] if the moon-thing actually is too unrealistic you could accomplish something similar with an Eyeball Planet. <https://www.space.com/20856-alien-planets-eyeball-earths.html> The life living further towards the shadow-side could just reference deep-sea creatures, arctic creatures and troglobites. <https://en.wikipedia.org/wiki/Deep_sea_creature> <https://en.wikipedia.org/wiki/Wildlife_of_Antarctica> <https://en.wikipedia.org/wiki/List_of_troglobites> ]
[Question] [ I'm writing a heist/caper type story in a fantasy world with a technology level that is pre-industrial (also, no guns yet). I'd say the world overall is closer to 1450-1500 in terms of technology, but I'd say 1700 is the limit. My story involves the robbery of a casino/gambling house. However, I'm running into trouble figuring out what sort of security they would have in place. How would security be provided with low technology? Guards presumably, but what sort of physical set ups might be put in place? While the world does have magic and I am including that to a degree, I don't want the security system to be some vague "protective spell." Thus, I'd like answers to be science or history based. [Answer] First of all, your best bet for security in any age is a bunch of locked doors. These offer the narrative possibilities of finding the key, or picking a lock as a guard walks around the corner. I assume you want some more, though, and since you've got a casino I get the feeling you want modern-feeling security measures. For that, the first thing that comes to mind is a tripwire attached to a bell. It wouldn't be too hard to implement, and in a world before electricity there are a lot of dark places to trip up a burgular. There could be many wires and many bells, all in some centralized location, so only one guard could 'patrol' a large portion of a building. If this is a building built for the purposes of security, you could have the corridors specially constructed to carry sound. Perhaps there are special holes in the ceiling, and no carpets/tapestries to muffle the sounds of thieving footfalls. Maybe there's also a series of mirrors, allowing a guard to see around corners or even to the other side of the building. And don't forget communication, in a big enough space your guards are going to need a horn or something with which they can signal for backup. All of these methods could also be used by a smart thief to trick the guards and send them the wrong way, but they also present a serious threat to the unprepared. There are a lot of more dangerous security measures (see pretty much any fantasy video game), but these options make it pretty easy for the owners of the casino to get around without worrying about their safety. [Answer] There are likely to be a few mundane security measures in place: * safes date back to [Pompeii](https://en.wikipedia.org/wiki/Safe#mediaviewer/File:S03_06_01_024_image_3158.jpg "Pompeian safe"), so having a safe or other strongbox would be entirely reasonable * jails (with their metal bars) are very nearly as good as keeping people out as they are at keeping them in * security guards (well, those that hold that title, anyway) are likely to be in evidence (whether they're *trustworthy*, however, is another question entirely) * any number of traps might be available (Pathfinder has a fairly [long list of traps](http://www.d20pfsrd.com/gamemastering/traps-hazards-and-special-terrains/traps#TOC-Lists-of-Traps "Pathfinder Traps"); anything with a CR of 5 or lower is likely to be plausible); note that, depending on the local constabulary, traps that have a high likelihood of killing the person that sets it off may be frowned upon * surreptitious surveillance slots seem certain With the addition of even "simple" magic, you could emulate a lot of very high-tech security systems: * magical doors may be impossible to open (short of knocking down their wall) without a specific token (key-card reader) * magical detectors could alert security when people enter certain places (laser grids, IR motion detectors) * scrying devices could allow a few guards to remotely view large areas of the casino (security cameras) * that [Pathfinder trap list page](http://www.d20pfsrd.com/gamemastering/traps-hazards-and-special-terrains/traps#TOC-Lists-of-Traps "Pathfinder Traps") has some suggestions for what kinds of triggers various magical traps might use Since you're writing a heist story, the magics could well have external pieces which would allow the robbers to affect them (eg., enchanted tracery which, if damaged, will allow the thieves to bypass the detectors), or may be able to be fooled with sufficient preparation. [Answer] Casinos look a little more secure then they actually are. The big hole in security now, and as well as in the age you are looking at is that they need large amounts of cash at hand. That's cash that is at the cashier and at the table games they might play. There is cash that is coming in constantly from the players, and cash to pay players off that simply needs to be easily accessible. One can go in a modern casino today, and at the main cashier there are millions in funds, that sit in a drawer unlocked if the cashier is standing there. There is no particular security that will stop a determined thief. There are no armed guards, the clerk is going to hand over the money rather then risk their safety. Back in the era concerning your question, the setup would not be much different. There would be a safe, but it would be in a back room. The clerks station, called a cage today would still be rather exposed and set up to move money with very little if any security that would stop a determined thief. The cage would be far away from an entrance as possible. This is true now and would be true then. There would not be anything to fancy in the way of security except bars on the cashiers window and ugly tough looking security guards. The main bit of security is that then and in the not to distant past, gambling houses were always owned and operated by people that were tough, mean, ruthless and had ways to get to anybody that robbed them, that conventional law enforcement did not have. In other words they were gangster types no matter what era they were in. They were well connected in the under world of things. It is quite likely that anyone robbing a casino was making a bad bet with their life, and this was the strongest deterrent to crime against a casino. For your story perhaps the actual robbery is not to complicated, getting away with the heist and staying alive long enough to enjoy the money is the main problem for the thieves. Some after thoughts: In the time frame your considering, in the western world at least, Casinos did not look like anything that one might imagine as a casino or gambling house. Table games like black jack, roulette and other games where one makes wagers against the house, and a employee is used to run the game, did not start developing until one or two hundred years after the tech time frame you are considering. The games before that would of been a poker type card game, were they are betting on some card game between the players, in the back room of the tavern. It might be behind a closed door. Your bandits will essentially be robbing the players and not the casino. The players would be playing with coin of the realm or gold rather then some type of casino chips, so most of the money to be had would be at the game and on the table. The games going where more of a private affair. One could not just walk in and sit down as you can do at a poker table or twenty one game today. The villains in your plot would need to connect to some degree with local gamblers to find out about the game, when it was played and about how much was being played for. Most gambling, especially at higher stakes was done in very private spaces, and the type of gambling in more public places like a bar that might offer some gaming was of a lower limit more sleazy type of character. The rich games were parlor games in the dukes castle or a rich business mans mansion. [Answer] A casino is different from a redoubt. A redoubt is designed to withstand a siege. Casinos are expected to deal with less than that, but they have to be subtle. Visibly paranoid security discourages the clientele. Assuming they have enough cash to protect, there will be guards at all times. However, we know most of the cash is in the vault. The more accessible the vault is, the less cash has to be available at the cash-out stations. The harder it is to access, the more cash you have to have at the cash-out stations. They will balance this, so the vault isn't inaccessible. Because we are not worried about a glorious siege, the real goal is not to stop an attacker, but to force them to reveal their attack. A military fortress may need multiple layers of thick steel, but a casino would rather have a single thin layer which is only accessible from a very visible place. Assuming the casino is legal, any attack which has to be visible for several minutes will fail when the casino notifies the local authorities. I would expect security measures such as locks, as well as attention-drawing features like nightingale floors. While security cannot be visible on the floor, once you enter the underbelly of the casino, I would expect several independent security stations which can cross-check each other. As a fancy option, consider making a vault door that is slow to open. There are several mechanical contraptions which can function as time locks. If these time locks ring a bell in several monitored locations, it would be remarkably difficult to enter the vault unannounced. As an even fancier option, for Casinos that handle ridiculous amounts of cash, you could have a really interesting puzzler for your thieves. Its utterly overkill, but it's what I'd do if I got really paranoid and had lots of money. My vault would be split in half. The outer half would never contain more than a few hours cash, and a time delay of maybe 30 seconds to open the door. Between the outer vault and the inner vault would be an observed hallway with two distinct observation rooms, with several layers of glass and metal between them. The door to the inner vault is on a much longer time delay (perhaps 5-10 minutes). The doors between the outer vault and the hallway, and the door between the hallway and the inner vault are both rigged to never be open at the same time, and can be locked down by either observation booth. It should be possible to transfer cash from inner vault to outer vault or vice.versa under the watchful eye of both observation rooms. Any thief seeking to waltz in would have to compromise two independent observation booths without alerting the other to what is happening, and would have to maintain that for 5-10 minutes while the timelock does its magic. [Answer] There's a number of possibilities and I feel they fall into several categories. The low-tech: * Locked doors * Brawn (just positioning guards, possibly using big weapons to look scary) * A vault * Tripwires * Dogs to sniff you out * Architectural defenses (make it hard to reach the money or give your guards an advantage in detecting or taking care of thieves) The second category is where magic meets technology. Basically, this is where you take a current piece of technology and simulate it using magic instead of technology. This could include replacing security cameras with scrying, replacing card readers with magical token scanners and things like that. The third category is purely magical. Magic does not have to be vague and can in fact be very concrete. * A magical alarm that alerts someone as soon as anyone enters a certain area * Mind-readers walking through the casino to discover the miscreant before they even break in * A vault that requires magic in order to reach it or to survive being in it * Magically marked funds (it's sort of like marked money, but much trickier due to the fact that they can use magic to locate the funds rather than having to wait for it to resurface) * Magically hidden or locked doors can require you to do any number of things to open them - after finding out what to, that is Note: I didn't make all of this up myself. I tried to gather, summarize and categorize what others said, and added a bit of my own in the last category. [Answer] One way is to place everything in plain sight. The cash cage is in the center of the room, visible to everyone, but close bars/mesh prevent access apart from through slots and one locked gate. Try to rob it, you have to get past *everyone* in the building. Downside in this security is if you breach it, there may be a stampede of patrons to take advantage... But if you can arrange it so that anyone accessing/raiding the vault would be visible to those in the room, and would have to leave through them, then you've done well. Security is best when multi-layered. Access corridors should allow viewing of those who approach. There should be dummy vaults and other misdirection, big security for a vault that contains only casino chips. Lots of ways to view people approaching the vault, lots of ways to prevent them arriving, lots of identity checks, lots of ways to prevent magical approaches, magic nullifying fields, etc. In a world with magic, the *actual* vault could be an airless vault carved of bedrock 50 ft below the ground, filled with superheated oil, with no tunnel or passage leading to it, and only the money, a number of golems, and small one-way airlocked portals for moving money in or out, only openable briefly, at specified pseudorandom times, by a trusted mage, when a golem briefly disables a specific ward that would otherwise prevent teleporting, and the money capsules only be safely openable after cooling, etc etc. End of each night, the profits go in. End of each month, wages are drawn out. Each coin of the money itself could be cursed to cry out when taken until returned to the oil. Or to silently report its location to the mages. Or the conveniently carriable bags that it's in could do this, thus using fewer spells. Wards (and backup "tripwires connected to bells") could detect digging, and other voids could be filled with acid to discourage random digging. [Answer] Architectural Defenses : moving out from the most secure, inner chambers... The secure portion of the building should lack windows and should circulate air using funneling [wind catchers](http://en.wikipedia.org/wiki/Windcatcher) with openings too small for even a trained monkey to fit through. This secure potion should be accessible only via a single entrance involving a long narrow corridor with [murder holes](http://en.wikipedia.org/wiki/Murder-hole) and [ankle breakers](http://en.wikipedia.org/wiki/Ankle_breakers). The corridor should be so narrow that only unarmored men can traverse it and even then they must go single file. No light should be provided, requiring that visitors occupy at least one of their weapon hands with a torch. As BowlTurner suggested, a maze would also provide effective low tech defense, so the single corridor should be surrounded by a maze of branching corridors with lots of complicated loops and a few dead ends. The security guards who actively guard the more secure portions of the building should get their daily exercise by roaming the maze, skuffing their shoes so that all the paths (including the one that leads inward) all are equally worn. The maze is not full of traps. It doesn't have to be. It's job is to delay and divide any group of attackers. Outside of the maze there should be a wide open corridor which serves no other purpose than to divide the secure portion of the building from the general access areas. A line should define the midpoint of this corridor, with elaborate warning messages and threats. Anyone crossing this line without authorization should be considered a thief and terminated without delay. Thoughtful building design can go a long way to securing an inner chamber without requiring any modern technologies or intensive magics. [Answer] For security pre-industrial world with bit of magic, get inspired by [Night Watch](http://en.wikipedia.org/wiki/Night_Watch_%28Discworld%29) from Terry Pratchett Discworld series. Plain old foot guard with [halberds](http://en.wikipedia.org/wiki/Halberd), spiffed up by werewolves if some sniffing is involved, a troll with catapult for firepower, and gnome flying on bird for mobile communication and air view. Especially werewolves (in their wolf form) would be effective for your door security. [Answer] The vault could be at the center of a maze, the secrets only known by a few. The majority of the house take would be hiding there, so running capital would be in a less well protected area, with a substantially smaller payday should it be robbed. You could even have 'safe deposit boxes' differing distances into the maze, that those with money could pay for to keep their valuables safe, the farther in the higher the cost. The maze could have many mundane traps and dangers, as well as differing levels of magic. ]
[Question] [ How can I increase the G tolerance for a person who will be participating in intense side to side/lateral movement as well as some vertical high G maneuvers. Ideally the application should be able to fit in a small vehicle/ platform that is capable of combat or intense racing. Visibility doesn't really matter in this case, So far I've looked at liquid immersion and directly pumping to the brain but those lead to more questions than answers. Anyone whose ever played Wipeout, Redout or even Armored Core 4/4A would be with the intense side to side movement that is being put on the pilots. [Answer] You can do multiple things (with current-day or near future tech): * Remove perceived lateral acceleration in the pilot. Do this by encasing the pilot's compartment in a rotating sphere, that always rotates so the pilot is sitting upright relative to the acceleration. If you center the pilot's head in the sphere, you might also reduce motion sickness. * Use compression suits like those fighter pilots use. These compress the lower body during high-G maneuvers to prevent all the blood moving downwards. Ideally, you'd put the entire pilot in some sort of skin-suit which can compress and release on digital command. * Drugs and external blood oxygenation can help. Dimenhydrinate or brand name Dramamine can reduce motion sickness and nausea, which will probably be important, but there are probably more drugs out there that could be useful to maintain consciousness or increase alertness. Additionally, an external-blood oxygenation machine can extract and insert blood intravenously to the pilot who might have difficulties breathing at high-g levels. * Liquid breathing is a possibility, and already works today (it just feels like being permanently waterboarded though) and would help prevent your lungs from being crushed. Unfortunately, it also adds a lot of inertia to the body, which could be dangerous in high-jerk scenarios. [Answer] **Other than not actually being in the pilot seat and doing it remotely i.e. from another location? Not much.** The key problem is that we long ago reached the limits of what pilots can take in terms of G forces and still make an active contribution to flying the machine. And this limit is way below the structural integrity limits modern material science has let us build into aircraft and other machines. Pilots with the best available g suit? Can sustain 8 or 9 Gs for short periods. Modern carbon fiber/metal alloy and other high tech materials in an airplane? Can endure something like twice that amount of G-force (or more) before they reach their 'fail points'. I'd have to find the exact figures but they're available on the net somewhere if you do a little digging). All of which means an unmanned plane can theoretically dance rings around a manned one all day long and not get 'tired' from pulling high Gs. In fact although air forces all over the world will fight the idea it looks like the days of the 'Top Guns' is drawing to a close and drones will rule the skies. Sorry if its not what you want to hear. You may have to go with some kind of SF gel or liquid life support tank after all. [Answer] **Rotate the pilot to compensate for high G.** The problem with high G maneuvers is that the heart cannot move arterial blood up to the brain against the acceleration and the pilot blacks out. If you put the pilot head down then arterial blood gets there fine but cannot get back to the body through the veins, which rely largely on gravity. Spinning the pilot cancels these out. On the down spin the pilot gets blood to the brain. Coming back up drains the blood from the brain. The action of the heart is augmented by the Gforces. Really it is not a steady spin but a fast rotation to head down, then back up, then head down etc. Ideally rotation to move blood to head has the feet at the center of rotation, and rotation to move blood out of the head has the head at the center of rotation, to maximize centrifugal forces moving the blood where you want it. Of course the spin must align with the Gforces but this is easily done; the pilot seat is mounted on gimbals and spin is according to an accelerometer that detects forces on the pilot. What, your pilot says the spin chair is icky? That he feels noshus in the spin chair? Did you tell this pilot what this mission entailed? Dutch you can go ahead and patent this. But I want a Tshirt out of the deal. [Answer] 1. AI in the pilot seat 2. teleoperation with ansible link 3. the "Ubik spray" - lengthens indefinitely the half-life state of otherwise a dead and frozen solid pilot, encased in an indestructible carbonite cocoon and neurolinked to the vehicle/ship command (my humble apologies, Master, for playing with your toys. No disrespect meant) 4. transhuman in the pilot seat - a former human mind (not the brain) - copy/pasted and operating on a cyber substrate, integrated with the vehicle/ship commands 5. "the instant medusa" device - puts the pilot in a (cryo?)statis the moment the acceleration passes over 3g and releases it when it gets back. Disadvantage: can't chain humongous-g maneuvers 6. "the squash machine" - deforms the metric of the space the pilot occupies so that the height of the pilot becomes negligible, and also negligible effort of the pilot's heart to pump blood (like... really?) God, it's so good when you can let science-based aside and handwave a storm of plausible technologies without conjuring magic [Answer] In addition to other good answers: 1. More-than-human pilots designed specifically for piloting 1.1. Biologically advanced pilots with more powerful circulatory system (probably duplicated), muscles and probably skeleton. It could be done via: surgical intervention (less likely), specific breed of humans or **genetic modification for each pilot** (more favorable for me). 1.2. Technologically advanced pilots: **implants** that help and/or duplicate heart, muscles and nerves/reaction. 2. Handwaved `gravity compensator`. There is no description how it works. This black box just works. 3. **Special drugs** which intensify almost anything needed for piloting at high G. There are drawback: each drug intake reduces life for N years. Another drawback: pilot could die immediately with some probability. [Answer] Have a rotating chair. Humans can take acceleration pretty well when it's in the direction they're facing. Have a chair that automatically rotates them with the vehicle, so they're always facing forward. [Answer] It's been a while. whew. In addition to being place inside a gyroscope to cancel outside to side acceleration and jerk, as in addition allowing for perpetually lying flat, that being what covers die to the side acceleration as Willk..... **Arterial pumps** With the said arteries being pumped by mechanically enhanced capillary actions, these falling into two families, those being arterial pumps, and literally just replacing the heart with a mechanical heart. The first, more original, and probably a bit less practical, would be arterial pumps. The capillary action by which blood is squeezed through veins being made more able to convey blood under stress, the natural squeezing and compressing of the veins literally being made stronger and able to convey more blood, with the means of the casings function being something that's plausible enough to not cover. The second, the significantly less original one, which also happens to be more practical would be the replacement of the largest arterial pump, the heart, being replaced with a better performing mechanical one. This allowing for continuous blood flow to the brain and the body when under high g stress, that being the effect on the human body with regards to high g forces main concern. [Answer] # Taking the modern-day safety features to their extreme The things that really damage you with G forces are your blood and organs being pulled inside your body. With collisions, the sudden change in direction can cause your brain to push against the inside of your skull. Pressurized suits can help keep your blood flowing at higher G forces but will not help with your brain rattling inside your skull. The way modern day cars deal with this is through crumple zones. These are parts of the car designed to fail during a crash in such a way that they extend the length of the crash. A longer crash means a longer duration over which your forward motion comes to a halt, meaning a less intense G force. On top of that, cars use airbags to slow down your body as it moves forward and giving you a softer surface to crash into. Taking these two ideas to the extreme, I can imagine that a driver who expects to crash a dozen times in a race would have a dozen permanent airbags surrounding them, making sure they are surrounded by soft surfaces. And their car might have several break-away pieces on the exterior that each serve to soften one or two hits before being discarded. They should be wearing a flight suit, to keep their blood flowing even at higher G's. And as for the brain rattling... I don't think any modern technology will help. Modern-day professional athletes often retire early due to brain trauma (Boxing and Football especially). If you're dipping into Sci-Fi or fantasy, you can invent some device to solve this issue. [Answer] **Neutron stars!** This idea is a bit on the futuristic side, but assuming a civilization has neutron star material available to them, this idea would work. Since general relativity tells us that gravity and acceleration are equivalent, putting a piece of a neutron star in front of the pilot when they're accelerating effectively cancels out the g-force, and provided with enough mass, would make almost any acceleration speed possible. The piece of neutron star is rotated to the direction that the pilot is accelerated, and in order to compensate for different accelerations (or none at all), the piece can be moved back in forth to increase or decrease the gravitational field strength on the pilot, which is the amount of g-force gravity can provide. This method will be less effective on up/down accelerations, because the field strength will vary more from the head to the feet, but considering that all other methods aren't even attempting to have an equal force over the body, I think that this in an excellent method. You can be flying at over 200G, and feel effectively weightless! Now all we need is to go find that piece of neutron star... ]
[Question] [ Space is useful for storage. In the future there is a thriving space real-estate market. Generally speaking, space in orbit is more desirable than outer space but both have a market value. 1. How can space in orbit be allocated and sold? How can an owner prove that they own that orbit or part of an orbit? 2. Is it even possible to sell chunks of non-orbit outer space and how could it be delineated? --- Assumptions 1. In general, the laws of physics are the same as today except that we know much, much more about them. 2. This is the far-future so FTL is allowed. However it is strictly regulated to prevent horrendous collisions. There are 'shipping' ports that must be used with clear known destinations. 3. You may restrict your answer to Earth, Earth and Moon, Solar system, or other areas of space as you prefer. I suspect the rules will be pretty much the same everywhere. 4. If you wish you can assume galaxy-wide space exploration and that some planets are more valuable in terms of resources than others. 5. Some of the volumes of space can just be used as parking bays for spacecraft. [Answer] Right now, the space is free. However, certain orbits around Earth, like Geostationary orbits are very valuable, and clash of interests is becoming common. What are the next possible steps in the development of "Space Law"? **Step 1: Space is too crowded to be free for all** Most companies and governments will recognize that satellites can no longer be put into orbit without coordination with others. This development is already underway: [Geostationary orbit allocation](https://en.wikipedia.org/wiki/Space_law#Geostationary_orbit_allocation) **Step 2: International authority to allocate space for free** To establish universal regulation, an international space authority will be formed. It will be tacked with tracking all existing satellites and issuing permits for the new ones. At first, this will be done for a nominal fee. Next, we will see auctions to get permission for some more valuable orbits. **Step 3: Monetizing orbits** After "Orbit rights" are established, a secondary market of reselling orbits will flourish. A secure way of delivering multiple satellites sharing the same orbit will provide a way to own a "chunk" of orbit. After space around Earth is commercialized, the process can be repeated for other parts of Solar system. [Answer] I guess what would have to be worked out is getting the material from the planet out into orbit. Getting material to outer space is extremely costly. It costs $10,000 to put 1 lb. into Earth's orbit. So that cost has to be factored in the market value. Enough competition could bring that down. If there are multiple companies, they could own 3-D chunks of space around the earth beginning at the Karman line (100 km) to 1500 km. If it is just storing personal items or things that are non-scientific or hazardous, then I would think the lower orbits would make it easier for retrieval. I think that orbital storage would most likely be used like a safe deposit box: you put very valuable things in it that you're not going to need for a long time, and then retrieve them if you need them. It does not really make sense to own "part" of an orbit unless the person who was storing stuff was paying multiple companies based on how much time the orbiting module spends in certain regions of space. I think instead there would be lanes set up around the earth that different companies would own. Your orbiting storage container could orbit within their lane. There would also be a separate set of companies that offer space-debris insurance. Right now there are tons of satellites that are put out of commission by small particles careening through space. I'm picturing the economic chain would work like this: Storage containers that can protect your valuables from space debris and radiation, as well as extreme temperature. More expensive storage units have thrusters or some way to reposition the satellite for easier retrieval. A small group of companies would own "lanes" surrounding the Earth. A central registrar would keep track of who owns what lane and to ensure new lanes don't interfere. Certain lanes would be reserved for scientific research, while others would be for communications, while others can be used for storage. This has to be worked out because some satellites in orbit need to orbit at a certain path so that they can do their jobs. Space insurers will reimburse you the cost of your valuables should they be damaged by space debris. Satellite collisions are relatively unheard of because there is so much space up there, but I can see some enterprising company offering this for an extra buck. There would also have to be space insurers in case your orbital storage falls to the earth and does damage. The companies that own the lanes will most likely form a cartel and wash their hands of all liability when you agree to use their lanes. Low orbit ferry service: You have to retrieve your storage somehow, so there has to be a relatively cheap and easy way to bring yourself up to your storage unit or bring it back down to you. [Answer] Property rights only exist when there are laws which recognize and guarantee them. Laws only exist when there is an authority with the power to enforce them. So if you want to turn orbital space into a commodity which is traded on an open market, you first need some organization which is willing to create rules for the use of orbits and able to enforce those rules if anyone violates them. The details of how such an organization comes to be, how it's structured and organized is up to you. But the necessity of such an organization in the near future is already pretty obvious. Currently the main source of space law is the [Outer Space Treaty](https://en.wikipedia.org/wiki/Outer_Space_Treaty). It basically says that any nation can launch anything into any orbit they like, as long as it doesn't carry weapons of mass destruction. And if those objects cause any damage, the nation which launched them has to pay for it. But since that treaty was made, commercial use of space became more and more prevalent. And now we are just a couple years away of private companies being able to launch payloads into orbit without the help of any government. All that SpaceX still needs to operate independently of NASA is an own launch base - [which they are already building and are already using for suborbital test flights](https://en.wikipedia.org/wiki/SpaceX_South_Texas_launch_site). They are going to be the first privately owned company to be able to do that, but they won't be the last. That means civil law conflicts are going to arise. The OST was primarily written with governments in mind, so it is insufficient at covering the affairs of private companies. That means a reform of the OST will be inevitable in the next decades. This will very likely require some international regulation body with the authority to fine private enterprises which violate the rules and the capabilities to forcefully remove objects in orbits where they have no right to be. Regarding pricing of orbits: This is something which will very likely succumb to the laws of supply and demand. Just like any other limited resource. Beneficial but limited orbits, like low-earth orbits, equatorial, geostationary or [Lagrange points](https://en.wikipedia.org/wiki/Lagrange_point) will have a much higher demand than there is supply, so they will be as expensive as any company will be able and willing to pay. When there is no officially sanctioned market for trading orbital rights, then there will soon be a black market where people make backroom deals to move the rights to an orbit from one company to another in an inofficial manner ("the orbit is registered on us, but you can place your satellite there if you pay us $x per month through a straw man. You need to paint our logo on it and control it through our ground stations so nobody can prove we illegally traded an orbit, but you will be the ones who have full control over it"). But space is big. Very, very big. If you are not picky about getting a very specific orbit and just want your object gravitationally bound to the planet, then you will very likely be able to get some orbit nobody else wants for a negligible administrative charge. [Answer] **By one Orbit, get one for free** Any orbit around any Planet will have 2 Major factors playing into its value. First one being Altitute and 2nd the Orbital inclination, aka the Angle of the Orbit in respect to the Equator. In General, the higher your Inclination is, the more Valuable the Orbit becomes, for a few Reasons. First one, the View. With a High Inclination, you will pass over the Polar Caps and that is probably a good selling point. "See the Aurora From Space, daily". The next reason is that such an Orbit will Intersect with other Orbits at a way higher velocity so there need to be gaps. Gaps in which other stuff could be, thus higher Price. The Value of the Orbit will decress as Hight incresses, because there is Physically more space higher up and the View is less cool. So the basic rules should be: 1. Higher Inclination = Higher Value 2. Lower Hight = Higher Value In terms of Owning the Orbit, i would guess you cant just flat out Own the entire thing. Probably more a Buble that is on the Orbital Plane. So you could buy lets say a Bubble with radius 100km around your Station. It should be easy to understand that a higher Radius also means a higher price. **Lets buy some space** When it comes to buying space that is not in the Orbit of a Planet, its the same ideas. The more you want to more you pay. I could however see that everything outside of a lets say 100.000km Bubble around the Surface of a Planet is declared as International Waters. But since everyone wants Money, the UN or someone International would probably be the Person you buy a chunck of space from. [Answer] First, space is huge. Really huge. Generally if you want to put something in orbit and something else is already there, you just need to pick a slightly higher or lower orbit, or occupy the same orbit but some distance ahead or behind. The most valuable orbital real estate are geostationary orbits, because you need to occupy a fixed point above the equator to avoid moving in the sky relative to the ground. This is a ring of 130,000km of useful space. Maybe it is allocated in blocks of 10km or 1km to avoid near misses, allow for orbital approaches, etc. Once we split it into blocks, potentially multiple people will bid to occupy an orbital point because it is the ideal point for broadcasting over the US, or over the EU, or whatever purpose they have. Slots in geostationary orbit could be owned by the first occupying organisation, or claimed by the country on the equator underneath, or shared between all countries on that line of longitude. Slots over the ocean might be owned by the nearest country, or shared between the countries on both sides. But if there is lots of competition for a slot, someone can just build a suitably large space station to mount all the antennas or sensors required. You might have to rent both the space you need in the station and the frequency range you need to avoid interference with someone else. And your space station can be arbitrarily large, especially in the north-south axis Eventually you could end up with a 130,000km continuous ring - though this would prevent anyone from having geosynchronous satellites that occupy a geostationary slot or two, but pass through it north and south at the same time each day instead of staying above the equator. And you could have one or more space elevators connecting to the large stations in geostationary orbit, which also have stations at the counterweight point above them. The same logic would also apply to a space station at a Lagrange point, except ownership would either be claimed by the organisation that built it, a planet wide governing body, or the last organisation to seize it by force. For lower circular orbits, it is either a free for all, or you really need a planet wide body to administer claims. It would be very similar to a land registry today. Your claim could reference an altitude, and a phase parameter that would determine where you are in relation to everything else sharing the same orbit. This could be a position at a fixed point in time, and all future positions are then extrapolated from it. Satellites can have different inclinations and you ensure that they cross the equator (and each others orbits) at different times, or more likely everything forms a train in the same inclination, for a much greater density. The registry body will need to be closely tied to the local military - unregistered objects would risk being destroyed, or the flip side is that if there is no local military, there is nobody enforcing the claims. At some point it stops being useful to have lots of satellites, and we upgrade to bigger satellites instead. So we have a few rival GPS constellations with small numbers of satellites, but having lots of rival GPS systems just wastes radio bandwidth. We'll have thousands of LEO internet satellites, but there are diminishing returns once any user has a choice of a few providers and can see a few satellites overhead. Space based manufacturing or resorts - the bigger the better. Space based power can also just scale up if the number of satellites gets too high. Any elliptical orbits would risk intersecting anything in a circular orbit, so a satellite in an elliptical orbit probably has to take responsibility for avoiding anything in a circular shell as it passes through. Beyond geostationary orbits, there is going to be lots of empty space to go around. You might have some traffic control, but your main concern is probably planetary defence against kinetic bombardment, or smuggling, rather than traffic collision avoidance. The same logic would apply to any other planet, although they might not spin fast enough for geostationary orbits to useful. And asteroids are likely just claimed on a first come basis, though larger bodies might be claimed by governments, or could be self-governing. [Answer] # Space is Free. Owning space is not... Owning the space isn't all that useful--after all, space is, so far as humans are concerned, infinite. What is worth money is finding a way to use that space. You have to find ways to increase demand for the services that are necessary to actually utilize that space, keep it private, what have you. Rich people don't just buy the Amazon forest, they will buy private islands or chunks of the forest that they can use how they see fit. So your valuation would have to be based on what can be provided, including transportation, docking, and storage services. By docking in this case, we mean the ability to park objects within your "area" of space. In earth orbit today, orbits are already competitive, highly regulated, and expensive; as technology advances, more areas and better docking techniques could be employed, but the demand for owned space would be limited to useful orbits, or the occasional government/billionaire attempting to hold some area of space for a status symbol or for strategic reasons. In that case it's very like the oceans of today; having a dock with a motorboat that can go deep sea fishing is a lot more valuable than a document entitling you to a couple cubic metres of Atlantic Ocean. If I were designing an economic system, I'd make the space free, and regulate and charge people rent for transportation, storage, orbital communication, insurance, etc. [Answer] ***23rd Century Mineral rights:*** Everything would need to be relative and positional. for example, you control the space over the land you own up 20 kilometers. Ocean would suddenly become valuable. Geostationary satellites would need to stay in a fixed box or pay incidental usage fees. An orbiting satellite would constantly be racking up costs. You could sell your space rights much like mineral rights. Nations would own space up an additional 20-50 km. International organizations like the UN could run things like Lagrange points and become self-funding. Lawyers and governments would fill space with radars, scanning for illicit space trespassing, and courts would be tied up in litigation - but with advanced tech, it could certainly be done. Space much further out starts to become hard to govern. It may not be worth trying to assert such claims, and perhaps it can be limited to bodies and their immediate surroundings. Space expands exponentially, and (for example) the human race may collectively assert a property claim over the entire solar system out to, say, half a light year. Again, this is relative, so a passing abandoned alien space ship could result in interesting legal disputes. Mankind claims the ship, but the original owners want it back. The ship might be sitting still relative to the aliens, but our solar system is moving, so aliens with a different concept of spatial territory could have fierce disputes. For that matter, what happens when we find we are within an arm of the Galaxy claimed by another species? Does our positional claim hold up against their regional one? On the other hand, look at a history of colonialism and how that played out with land ownership. Perhaps humanity really DOES need clear claim to space, so some random wandering space hobo can't "sell" the solar system to aliens for the relative cost of a few strings of beads. [Answer] We could in theory just dissect space into 1m \* 1m \* 1m cubes and have an international organisation or initial colonisers auction it cube by cube. In practice though, what will matter is which portions of space are more valuable? Regions with more solar radiation or an optimal temperature or a desirable view could fetch more. If technology is as it is right now, objects won't usually be left stationary in space, they'll be left in orbits, which means soon enough entire orbits would be packaged and sold together. The sum is greater than the parts when you are selling a desirable shape such as an orbit. You also need laws that are implemented to ensure consequences for people who violate space boundaries. This needs the technology for it, as an accident in densely packed space could set off a chain of collisions with significant impact. Collisions will also give off tiny shards that would spread through space unless collected somehow. ]
[Question] [ In the book series I'm currently working on, there's an archipelago around the size of Australia that is headed by a single tribal chief in the capital city of Jubenar. The archipelago is very sparsely populated, being home to only about 5 and a half million people. This is extremely apparent when looking at the towns and capital, which are basically oversized villages. The majority of the population is rural and scattered among hundreds of small farming and fishing villages in the interior and along the coasts. This chiefdom is sort of halfway between the stone and iron ages, with stone tools being the norm but iron arriving through international trade is quickly picking up steam. In addition, the geography of this archipelago is extremely varied and rugged, as seen below on the Koppen climate map of the region: [![Koppen Climate map of the archipelago. Settlements with populations above 5,000 are shown as labelled dots. The capital of Jubenar is only home to around 60,000 people.](https://i.stack.imgur.com/mrAFh.jpg)](https://i.stack.imgur.com/mrAFh.jpg) **How could a tribal chiefdom based in what is essentially an overgrown fishing village govern what is basically a continent the size of Australia with extremely rugged terrain such as this?** Note: the culture and technology of this archipelago is largely based on those of various Australian Aboriginal cultures, with some Maori and Viking influences they picked up through trade with outside powers. Yes, I am aware this map resembles Greenland a bit too closely and I am working on fixing that, but the overall point still stands as the fundamentals of the climate and terrain types will not change much. Also it's probably worth noting that this archipelago's center pretty much sits directly on its planet's equator. [Answer] You have two distinct problems: 1. how to "convince" far away (and obviously loosely tied) communities to accept your authority as chieftain. 2. how to effectively control your "State". Easiest way to solve (1) is to have some resource absolutely needed by everyone and, at the same time, easily defended (cfr.: [Niven's "Destiny's Road"](https://en.wikipedia.org/wiki/Destiny%27s_Road); in that case it was a Potassium source). If "power" is "benevolent" there wold be little push to revolt. In this frame the most natural way to solve (2) is through the network of "trading posts" needed to deliver your "resource". You can devise a net of advisors/traders/shamans conveying the will of the "chieftain" out and "taxes" (disguised as trade earnings) in. In your archipelago I would have most of the commerce done with small sailboats (Polynesian style) keeping in the inside "lagoon". Many variations on the schema are possible and choice depends on what, exactly, you want to let happen in your world. [Answer] **Ignore semantics and go full feudal** What is really the difference between a tribe, a clan, a kin, a house? They are all terms used to describe an organizational structure of a people, that in each case are often (but not exclusively) heavily maintained by lineage. I could easily say Clan Targaryen and you know exactly what I'm referring to, with the preceding word holding only slight difference in meaning. Likewise, Chief has often been used simply as a way to downgrade the relevance of a leader who otherwise might be called a King. We say Native Americans had Chiefs, but Pocahontas was still considered a Princess. You have even already made the association within your question by referring to it as a "chiefdom" instead of a "kingdom". Basically my argument is that you can simply adopt the structure of Medieval Europe, or even Feudal Japan and change terminology and a few cultural aspects. A tribe and a chief are what you define them to be in the context of your story. [Answer] **Extended kinship.** A tribe is bound together via kinship. In your system you can use exchanges of noble boys and girls to cement bonds of kinship across this area. If we are local rulers but we share a grandson we have something in common. Perhaps the grand ruler will keep some children of local rulers in the capital for a time, treating them like his own children. They are hostages in a way but they become accultured in the ways of the capital and so serve as cultural ambassadors when they return home. This would be effective but not super exciting for a story. --- **Shaka-style, and brutal.** <https://en.wikipedia.org/wiki/Shaka> Shaka Zulu was a mid19th century leader who united Zulu tribes. There is a lot written about him but there is no question his methods were effective and brutal, crushing and slaughtering his opponents rather than simply defeating them. It may be that some of ideas about warfare and conquest were borrowed from interactions with European invaders and so gave his approach a hybrid vigor. This could work for your fiction. War tactics developed in a different part of the world (and probably one with surplus population; the Maori would work for this) are adopted by your leader and used against the peoples of his continent. It is nothing they have seen before and they are shocked and awed into submission. This also be effective and more exciting for a story. [Answer] # Soft power and local government The bigger question is this: why would the people want to rebel? A government can hold onto power by not harassing the people and not doing anything so objectionable that their citizens revolt. I live in the United States and we're taught in grade school that England kept piling on the harassments in the colonies until people finally had enough and launched the Revolutionary War. Both *Common Sense* and the Declaration of Independence describe these offenses. So the first approach is simply avoiding anything that'll make people fight you. The second approach is to empower local governors to carry out your objectives. This is a really difficult part. Too much local power and the governors might try to take power. Not enough local power and the governors would be seen as powerless. Realistically, this is the only way the government will be able to stay on top of what's happening in the far-flung regions. [Answer] **Because that family has always been technically in charge, and doesn't ask for much:** Tribal rulers either ruled by force or because it was tradition. Any sufficient pressure will cause people to rebel, and tyrants are always ready to be deposed by angry serfs. With outside higher-tech cultures beginning to influence your system, I would advise you go with the traditional approach. Otherwise, incoming traders will favor oppressed minorities and their efforts to rebel as a way to secure favorable trade. A lot of colonialism was supported by factions of the locals (at least initially) because the current rulers were worse. I would suggest that the ruling family is kind of the individually LEAST powerful tribe, and act in more of a court-like function, settling disputes and centralizing trade agreements with outsiders (or maybe this is the only family considered sufficiently pure to tolerate contact with outsiders; the options are up to you). The less the rulers impose on the people, the less the individual tribal leaders will be concerned about their tribes being exploited. A religious Rule is also very traditional, and again, the less invasive, the less the risk of rebellion. Perhaps the capital is the holy sight for their religion, and the ruler a hereditary high priest. Transportation can be vital in your system. With essentially a large, centralized sea, boats allow rapid movement of men & material, information & trade. The locals might insist foreigners aren't allowed to sail the sacred waters, securing the best trade routes for the locals. A prominent central island for the capital (not unlike some calderas...) would minimize travel time and make it worth it for travelers to stop there while trading (securing the best trade routes for the rulers) and if the ruler didn't need to demand taxes, who's going to complain about a guy who is only REALLY in charge when there's a foreign invasion or when your two sons are disputing which should be inheriting the local chiefdom? ]
[Question] [ Imagine a magic spell could allow to negate the firearms we know (edited) AND USE TODAY: what would be the one chemical process that operating in all of them needs to be blocked? If not, what would the exceptions or alternatives be? Which one the simplest? [Answer] The **TL;DR** answer is to prevent the oxidizer from reacting with the fuel in the bullet and/or gun, preventing combustion and thus the gun from firing. The full answer is a bit more complicated because there are multiple ways to create the pressure needed to shoot a firearm. The general way a firearm does its thing is through combustion and it is that reaction that our anti-gun magus wants to target. ### Example Propellant Common gunpowder, or black powder, commonly uses three things to make the reaction: Saltpetre (potassium nitrate), charcoal (carbon), and sulphur. When ignited, chemistry happens -- the reactants burn and release energy, which allows the reaction to continue until there is nothing left. The pressure has nowhere to go but out the barrel, pushing the projectile that is in its way out of the barrel at the same time. In the Wikipedia article for gunpowder, there are a couple of reactions using the three components of gunpowder in different ratios. The solid products might be different, but both of the reactions generates carbon dioxide and nitrogen gas. The oxidation of the carbon is the thing you want to stop in this case. The nitrogen is a side effect of the nitrate being broken apart. In this particular case, your spell needs to stop the saltpetre part of the powder from reacting. If the potassium nitrate in the powder can't react, then there is no bullet flying out. ### Spell Concerns If we use the idea of "Prevent Saltpetre from reacting chemically" as the base of the spell, then the first problem that can be seen is that any firearm that does not use that particular chemical as the oxidizer will work just fine. This might be an acceptable risk because gunpowder is the only thing firearms use in your world and it should always use it. It can also become an issue at a later date as people try to work around your anti-firearm spell by using different propellants for their arms, like guncotton for one. If you make the spell too broad, say "Prevent oxygen from reacting chemically", then the spell will not be just be used to prevent firearms from firing, but it will be used to kill people by preventing the oxygen in the blood from reacting with the body. IT would be a lot of collateral damage just to make sure a gun can't go off. The other concern is that depending on the knowledge of the caster, and/or the setting, the people that are creating the anti-firearm spell might not even know the proper way to refer to what they want to stop. This is neither a good nor bad thing, but something to take into account. If all the wizard knows is that gunpowder burns, and his spell is "Prevent things from burning themselves", then more than just firearms could be affected by the spell. What your spell can and can't do based on its parameters is going to be a function of your magic system. While not perfectly relevant, it will determine how specific one will need to be to get the effect desired -- an anti-firearms spell. ### Nitpicks From my limited research, if the tool uses compressed gasses to fire a projectile, it is an considered an air gun and not a firearm. However, it is noted that air guns can shoot things and cause real damage too. Along with that, there is no chemical reaction in an air gun that can be stopped to prevent them from firing unlike a firearm. [Answer] # Water and oxidation If you stop combustion, you'll keep the gun from shooting. In olden times, soldiers put considerable effort into keeping their gunpowder dry. That's because it's hard to ignite wet powder. Modern bullets are much better protected against moisture than powder horns, but they're still vulnerable. If you could cast a spell to put water inside of a bullet, most firearms would be rendered useless. Here are two other considerations that might be useful in your story. Another approach would be to oxidize the primer in the bullet. Basically damage it so the hammer strike from the firearm doesn't cause it to detonate. If you're looking for a magically weak point in the firearm and not the bullet, damage the firing pin. It's often much weaker than other parts of the weapon. Anything that could damage the piece in the photo would disable a military M-16. ![Rifle firing pin](https://cdn-fsly.yottaa.net/53ff2f503c881650e20004fa/www.brownells.com/v%7E4b.b4/userdocs/products/p_231000212_1.jpg?yocs=l_) [Answer] [The Trigger](http://www.infinityplus.co.uk/nonfiction/trigger.htm) by Arthur C Clarke and Michael Kube-McDowell is a sci-fi book which explores the implications of a similar '[spell](https://en.wikipedia.org/wiki/Clarke%27s_three_laws)' - a device which causes the *premature detonation* of (nitrate-based) explosives in its vicinity. Being Clarke and hence very hard sci-fi, the ramifications - and limitations - are quite carefully determined. Firstly as noted elsewhere, this is not the only chemical structure used in modern explosives (although it does cover the overwhelming majority of common firearms), and alternatives are quickly developed that are not susceptible, merely perpetuating the eternal arms race between offence and defence. Secondly, it only requires the application of human ingenuity to transform a defensive tool into an offensive one. A spell which had the effect of exciting nitrate bonds just enough to detonate explosives, without causing substantial disruption to more stable nitrate-laden structures (like animals) is perfectly plausible, and this would have the effect of neutralising most current firearms. The fact that such a spell is not a universal panacea is [probably a good thing](https://www.brandonsanderson.com/sandersons-second-law/), from a storytelling perspective. [Answer] Fire. As the name indicates, the gunpowder is oxidized. You need to stop that. (As a sideline, oxidizing fats, proteins and carbs is how your body fuels itself, so if you want to stop the gun and not gunner, you need to inhibit not oxidization in general, but that of gunpowder.) [Answer] Alternate approach: change the properties of air. Thixotropic or 'shear-thickening' materials like a mix of cornflour and water famously behave differently in response to impacts at different speeds. A spell that increased the binding energy of air would not impair normal movement or microscale movements, but would meant that any bullet-sized projectile moving at more than (say ) 30 m/s would be trying to move through treacle and would immediately become ineffective after a few metres. Such liquid materials are already being used experimentally for bullet-proffer protection (for example, making batteries bulletproof), a shear-thickening gas would be an extension. [Answer] ***Rust Never Sleeps*** Neither does Entropy. Accelerate entropy and you can kiss that firearm problem goodbye. One thing almost all firearms have in common is the barrel. This is almost always made of steel. It may be protected in various ways, because rust can either cause problems in the barrel or may weaken the entire structure. There is all kinds of materials in firearms from plastics to aluminum, but the barrel is almost always steel and therefore at least partially iron. So tailor an entropy spell that rusts iron. Even better if you can make it target Lead and Copper too. Rusting out the barrel will weaken the structure making the weapon dangerous to the person trying to fire it. It will may cause the barrel to swell, making it potentially explode behind a blockage. Not a good thing. In addition, targeting the metals most often used in projectiles is a good thing. Lead is what gives a slug mass, but it's a soft metal. That's why it is often jacketed in copper, so it will hold it's shape as it flies so you have more range and better penetration, or to get it to do thing on impact, like mushrooming out like a hollow point. Sometimes it will also have steel incorporated to make it armor piercing. Sometime environmentally conscious hunters will use steel shot in shotgun shells when hunting, so as not to cause lead problems in the wetlands. The purpose of using entropy on these metals is to make them too weak to hold together as a coherent projectile. The energy will get dispersed over thousands of particles rather than one cohesive whole. It will likely make the round sting, but not be lethal. Also, if the triggermen are cheap, they may try to save a few bucks, they may be silly enough to buy rounds with steel casings. Degrade the casing and the powder dribbles out and it won't have a good chamber to burn in propelling the projectile down the barrel. So target the 3 metals. Oxidize them, and your problem gets dramatically reduced. [Answer] Freezing spells. Stop the kinetic energy so the firing pin cannot strike the primer of the bullet. [Answer] **Fooling around with smokeless powder** A modern cartridge is a brass case with primer, a metal bullet (often containing lead) and a filling of granulated nitrated organic compound(s). If your spell, targeted to such cartridges, converts the filling to a fine powder, it enhances the pressure rise at combustion, destroying the weapon and injuring the user. On the other hand, you could solidify the powder, creating a solid rocket engine. It could create just enough pressure to push the bullet out of the barrel, dropping it harmless on the ground, followed by another second of flame. [Answer] **How to deactivate gunpowder** Sulphur, charcoal and saltpetre are mixed physically. They are loaded into a gun behind a lead bullet. Your spell targets this exact situation and orders the components to separate. If you have some energy to spare, melt the sulphur and solidify it as a membrane separating the other components. If someone wants to blast your fortification with a mine, create a guardian spell with similar workings. [Answer] A spell to limit the rate of reactions, or the rate of the change in pressure, or perhaps just not allow the pressure to go over a certain value - perhaps several atmospheres. If you still want chemistry to work, perhaps something just changes the rate at which reactions occur, could still allow reactions up to a certain energy to work, but limit other ones. That could still potentially have some pretty bad side effects since a lot of reactions are limited by the amount of materials that come into contact with each other, for example being limited by diffusion. So an alternative would be to target the rate of change of pressure and not allow it to change faster than a certain amount. Just when the gun-powder explodes instead of the pressure building up in the barrel, the magic in the area relieves the excess pressure to another dimension or something. Everything would kind of still work, but the bullet might not have enough force to leave the barrel, or just pop out at a fairly low velocity. [Answer] To prevent modern firearms from firing use a spell to transmute the mercury fulminate used in primers. Without a working prime the guns will not fire. This would not affect more primitive firearms like flintlocks or matchlocks. Eventually other type of primers would be developed. Water is the enemy of flintlocks and matchlocks. Wet gunpowder in the firing pans will not ignite. A sudden rain storm will make them much less likely to fire. You could also cast a spell to simply plug the barrel. The gun would explode when fired. more subtle would be a spell to warp the barrel. The gun would still fire, but most likely miss. This would not be effective at short ranges and would be less effective against weapons like shotguns or automatic weapons where the fire could be walked on to the target. Similar would be spells creating high winds or altering gravity. Another possibility is to cast a shield against fast moving objects. Thinks of the personal shields used in "Dune". [Answer] **Microportals** A microportal is a tiny ~~wormhole~~ sphere-shaped portal that leads to the plane of air, small enough to be invisible to the unaided eye. The spell creates an array of such microportals throughout the space. They are big enough for gases to pass through, but they automatically close when they detect a solid or a liquid. The spell has a variety of uses: * In the ~~default setting~~ most commonly taught form, they operate as a pressure relief valve. That is, while they won't prevent any fire from generating excess gas, they will happily remove that gas from the material plane as soon as it is produced. This wastes the would-be shooter's ammo, notifies everyone to their intent (it's not as loud as regular gunshot, but still very perceptible), and nullifies the deadly effect of any firearm or airgun within the affected area. Because of its general beneficial use, this version of the spell is also available in a totem form. Still expensive, but less so than hiring a human mage. * If the pressure differential needed to open the valve is reduced, this allows free exchange of gas between the two planes, and allows the spell to be used for general purpose ventilation. It's still expensive to maintain (can't maintain concentration 24/7) so it doesn't replace regular windows, but for an underground bunker for a couple of VIPs, it will do. * When the area of effect is reduced, this makes the cost more manageable. Small arrays will have found use as a form of water breathing for advanced mages - and, much later in the future, in the medical field. * Blood mages have learned how to make bigger portals, big enough to let liquids through, and how to make them spawn inside the liquids. As kids, they use it to empty people's cups, produce bubbles in bathhouses, and other minor nuisance, but soon they figure out where the most interesting liquids are. Remove blood from a person's arm and it hurts like hell, but remove blood from their head and they fall unconscious. Naturally, this practice is punishable by death in every civilized kingdom, considered a form of torture by the UN, and forbidden multiple times in the Geneva convention. Also, it is the preferred way of slaughtering animals for food, though still economically nonviable for the vast majority of producers due to extremely tight governmental regulations for the casters. ]
[Question] [ I was thinking whether neutrinos (or antineutrinos) could be used to propel space craft. This is because neutrinos are plentiful in the universe. What if neutrinos could interact through the weak force with electrons and this energy could be used to power the spacecraft? Would there be a tiny force, because even though the weak force is weak if there are many neutrinos this could increase the chances of an interaction? I'm looking for a reality check on this. [Answer] Neutrinos have, believe it or not, been proposed as a method of spacecraft propulsion - see [Morgan (1999)](https://ui.adsabs.harvard.edu/abs/1999JBIS...52..424M/abstract). The idea is a bit different from yours (which I believe has not been explored yet), inasmuch as it relies on the production of neutrinos, rather than using existing ambient neutrinos. This idea utilizes the decay of muons, heavier cousins of electrons. 1. First, protons and antiprotons are annihilated together. Some of the particles produced include charged and neutral pions. 2. Pions themselves are unstable, and so they quickly decay. One major decay product is muons. 3. Muons, too, are unstable. Initially, they are decelerated and then polarized. 4. The polarized muons decay. Their decay process involves the emission of a muon neutrino and an electron antineutrino. The weak force does not conserve [parity](https://en.wikipedia.org/wiki/Parity_(physics)), which in this case means that the emission of neutrinos is anisotropic, resulting in a net thrust in one direction. The efficiency of the process depends on the number of pions produced by the proton-antiproton annihilation, as well as what fraction of the momentum is carried away by neutrinos. Morgan estimates an efficiency of $\eta\simeq0.025$ from this implementation of the process. [Answer] The issue with harnessing the neutrino-electron interaction is the cross-sections involved. Since neutrinos are charge-less, and interact only via the weak force (gravity also but that won't help us here), they are more likely to interact with larger particles. For this reason, neutrinos-nuclei interactions are the most common. While neutrinos can (and do interact) with electrons, they will likely encounter a much higher number of nucleons first. [Here](http://benasque.org/2008nufact/talks_contr/123soler_lectures_1_and_2.pdf) you can find some standard information on the neutrino scattering cross-sections. Note that the lowest nucleon-neutrino cross-sections will be three or more orders of magnitude larger than the electron-neutrino cross-sections. Electrons don't like to be grouped together (both the electrostatic force and degeneracy pressure will push them apart) so to get a high enough concentration of electrons so that you'll be more likely to have e-$\nu$ interactions will be difficult. To compound this, high enough concentrations of neutrinos, to warrant enough interactions per second to result in energies required for propulsion, cannot be found anywhere except near supernovas and if you're near those, propulsion will be the least of your worries. For comparison, on the Earth, the highest concentration of neutrinos come from the sun, which is estimated to produce neutrino flux on the order of ~ $10^{11}/cm^{2} s$ ([source](http://www.sns.ias.edu/~jnb/Papers/Popular/Scientificamerican69/scientificamerican69.html)), whereas the interaction probability for a 1 MeV neutrino is on the order of ~ $10^{-11}$, for interacting with anything in the Earth as it passes through ([source](https://cds.cern.ch/record/677618/files/p115.pdf)). [Answer] If you manage to interact with neutrinos to any practical extent, a lot of possibilities open at once: 1. Energy from the star neutrinos - the Sun emmits some 15% of its energy in neutrinos, you can harvest them even in some planet's shadow. Hotter-core stars are even better in this regard. 2. Neutrino sails - to harvest neutrino momentum. If you can interact separately to high-energy star neutrinos and with low-energy neutrino background, you can use them both as wind-and-water marine navigation in whatever direction you like. 3. Neutrino cooling - you can offload some heat from whatever reactor you have to the neutrino background, instead or in addition of radiating it in electromagnetic waves. ]
[Question] [ Hello I imagine this is a pretty straightforward question, perhaps already covered in another post, but I wanted to get extra perspectives and options for achieving this type of planet or moon. So yeah the topic in question is how a planet or moon could have a variable day/night cycle throughout its solar year. Example: I'm looking for a planet or moon where one period of the year it is day for 48 hours and night for another 48 afterwards. Then in another period it could be 23 earth days of daytime then 23 earth days of nighttime. I am looking for something that is very reliable and consistent and it has to still allow for the planet or moon to be relatively habitable at least in certain areas or during certain times in the yearly cycle. The idea would be similar to how some parts of the year up far north have long periods of almost total night or total day. However this would be found in other latitudes and the length of day versus length of night would stay equal. The important part is that this would be very consistent so any civilizations could actually map out when the Ever-Day (very long day) or Trailing-Night (very long night) would occur. Eclipsing effects to achieve this effect are ok, but if there is a way to do this without having the planetoid's star obstructed by another body that would be preferred. Elliptical orbits I imagine are the way to go with tidal locking playing some kind of role, but I don't really know. Any avenues no matter how out there are encouraged, but this is meant to be a scientifically plausible world not reliant on hand-waving magic stuff to explain everything. I look forward to any of your creative ideas and thank each of you in advance for your help. Edit: Never mind I underestimated this concept, ignore my initial statement this is not a straightforward question my apologize. However this makes it even more interesting! [Answer] > > if there is a way to do this without having the planet's star obstructed by another body that would be preferred. > > > I don't really see how, tbh. The problem is that even with a heavily elliptical orbit, your planet's rotation is always the same. An heavily elliptical orbit would certainly give you a wide variation in seasons depending on distance, but your day/night cycle would always be fixed with the planet's rotational period and nothing you do with orbits can change that. The only thing you can do to make the day/night cycle vary like this is decouple it from the planet's rotation, which means you need a more complex relationship than just "Planet orbiting a star". "Planet orbiting a gas giant" could work quite nicely. The scenario that seems most plausible to me would be to have a habitable planet orbiting a gas giant that has a dramatic axial tilt relative to it's orbital path around the star. Imagine taking Jupiter (or Saturn, if you prefer) and tilting its axis of rotation (and that of it's moons) 90 degrees. You would have two points in the gas giant's orbit where the axis of rotation would be pointed directly at the star, and thus one hemisphere or the other of the satellite planet would be receiving sunlight continuously (call these the solstices). At two more points of the gas giant's orbit the axis of rotation would be parallel with the gas giant's orbit, and you would have day/night cycle that's directly tied to the rotational period of the satellite planet. (call these the Equinoxes) If the moon is tidally locked then whichever hemisphere is pointed at the gas giant is going to have regular eclipses as it will be passing 'behind' the gas giant relative to the star. You'd slowly cycle from each condition to the next as the gas giant orbited its star. For reference, if you assume Jupiter's values, one cycle would take a bit less than 12 years. Your satellite moon would have a couple years of arctic winter in the northern hemisphere, followed by four years of transition to a summer of continuous daylight, and then the process reverses itself. Depending on proximity to the Gas Giant, your satellite moon could have an orbital period (and thus a day/night cycle) of anywhere between 40 and 400 hours if you want to keep it within the same kind of orbital distance as the Gallilean moons. [Answer] This is sort-of what happens when you have a planet orbiting a single star in a binary system. In the Illustration below, let's assume the green planet has a 96 hr rotational period. In position #2, the stars line up and you have a 96hr day. In position #4, you have two Noon times and 2 twilights giving you sort of two 48 hr days. If your planet has an atmosphere that creates particularly strong rayleigh scattering, if your species can only see in the more reflected wavelengths, or if they just have poor low light vision, these twilight periods could appear like night time. This may not be exactly what you want though. In positions #1 and #3, you will have an extended day cycle and a shortened night cycle; so, the duration of the day will not scale uniformly, rather it will be an anomaly of a certain time of the year that you get 2 apparent days per rotation. [![enter image description here](https://i.stack.imgur.com/HWhzR.png)](https://i.stack.imgur.com/HWhzR.png) Another option that fits better in some ways but worse in others would be a tidally locked moon on an irregular, not fully true orbit. This can give you the day length variations you are talking about but these orbits are unstable. No planet or moon would ever form on such a trajectory, but if you have a dwarf planet or large asteroid that gets swept up in the gravity of a larger passing world, its initial orbit will be erratic, and it will take a long time for it to settle into a stable orbit. As the orbit begins to settle, it will begin to develop an increasing level of predictability, this means that you may develop a pattern of orbits where some take much longer than others as it in some cases passes in close and in others swings out wide. In geological or evolutionary time this would be a temporary condition, but in the lifespan of a civilization, this could become all they've ever known. One caveat with this kind of situation is that these variations will have nothing to do with time of year. You could have several "day seasons" in a year, or several years in a "day season" just depending. Another is that 48-96hr is a pretty fast lunar orbit. Your best bet to achieve this kind of orbital speed is to be in a relatively close orbit to a gas giant. At the required distance, your planet would experience tidal forces over 10,000 times of that which the moon has on Earth. Being tidally locked will hopefully prevent the worst of the damage that this would otherwise do, but since you are on such an irratice orbit, your tidal lock is not going to be perfect; so, the wobble of your moon relative to the plant is likely to cause some serious tides. [![enter image description here](https://i.stack.imgur.com/cjRmh.png)](https://i.stack.imgur.com/cjRmh.png) [Answer] The largest problem with changing the day-night cycle duration is that rotating planets represent a massive amount of angular momentum, and making changes to that typically involves 'unpleasant things' having to be done to the surface. --- A highly elliptic orbit can induce heavy seasonal influence on a global scale, as opposed to earth's seasonal influence on a hemispherical scale, but you're not really going to easily impact your day-night cycle with one. Instead you'll have extremely hot [potentially dangerously so] days on the short end of your orbit, while having extremely dim and cold days on the long end of your orbit, but the time from sunrise to sunrise remains the same general average. --- The easiest way to change the solar day duration for the surface of a planet is to uncouple the surface from the core, and introduce additional mechanics - In other words, don't make it a planet, make it a planet scale *machine*. Your surface isn't just the crusty cool rock layer floating over a molten core slowly marching its way towards the eventual heat death of the universe, it is *a fly wheel of a giant machine...* Exactly what the machine *does*, or even who built it, isn't overly important, at least to any civilization who might arise on the outer surface of this "fly-shell", and how much they understand of it isn't overly important to the machine itself. All we really need to care about is that it transfers momentum back and forth between its shell and core while following a consistent process on a regular schedule. Those on the surface might observe some odd effects beyond the change of day-night cycle duration, and possibly some electromagnetic emissions, but our machine can merrily chug along for eons doing its thing while scientists on the surface debate the nature and structure of what's hidden inside their 'planet'. [Maybe part of our world building is that some overly clever person or group of people suspects that maybe there is more to the planet than molten rock, or maybe everyone just shrugs and goes on about their lives with fancier clocks and the mindset of "Well that's just the way things are..." with mild suspicions of it being kind of weird.] Whether the machine-planet is an intergalactic dooms day device or merely a failing grade science fair bauble of a hyper advanced civilization is far less important to us than the fact that the outer shell exchanges angular momentum back and forth on a regular basis... --- Other 'slightly' more plausible options may involve getting weird with the material and structure of the planet's core [And thereby having to put up with some community members raising a stink about the planet no longer counting as a planet according to IAU...] such that its rotational properties are not entirely stable. --- [While probability of many suggestions in various answers may strongly approach zero in our real universe, we don't have to settle for such boring realities in Fiction...] [Answer] Several factors can change your very complicated planet’s day cycle through the year. All of these require your planet to have a shifting mass area, and for your particular case, a very large mass area. Venus has a variable length day by 7 minutes, and [part of the explanation](https://phys.org/news/2018-06-explanation-varying-venus-rotation.html) is that mountains stop the flow of clouds (mass stops rotating). That only accounts for 2 minutes, the rest is a mystery. **Dynamic braking of the magnetosphere**: Your planet’s core is molten iron with a very unique cycle which repeats every year. This planet is a huge magnet like [mercury](https://en.m.wikipedia.org/wiki/Mercury%27s_magnetic_field) which generates a magnetosphere from the solar winds. [![Mercury's magnétopause](https://i.stack.imgur.com/rhrti.jpg)](https://i.stack.imgur.com/rhrti.jpg) What makes your system even more complex is the sister planet orbiting it (or a very ferrous moon), drawing some of the magnetic flux away for certain parts of the year, which changes the shape of the magnetosphere. The magnetosphere and planet core form a motor which accelerates and decelerates the planet through the year. Also, the planet’s liquid core is rotating at a different rate than the crust. Both core and crust are heavily ferromagnetic, and they contribute to the motor action. The timing of all this flowing material, binary orbits, and solar winds is beyond miraculous, but the existence of it is not beyond what is physically possible. Calculations for a system like this are beyond what we understand today. The answer: Magnets. I defined “fairly habitable” as simply meaning it has a somewhat constant orbit. And much of the planet’s surface would normally be ripping itself apart, so you’ll need a new question to see if it’s possible to control the tectonic activity on such a planet, with some sort of amazingly smooth and uniform liquid lower mantle. The gravity of a sister planet or moon makes this even more problematic. [Answer] Your planet/moon is small, so it has not pulled itself into a sphere. It is lumpy. As such, under the gravitational influence of other celestial bodies, its rotation is chaotic. While the angular momentum of the world is constant, its axis of rotation changes constantly, as does its moment of inertia and thus length of day. There are several moon in the solar system that work like this. Hyperion's rotation is so chaotic that NASA could not reliably schedule passes of the Cassini probe to scan new areas of the surface. Pluto's moon Nyx can have days where the sun rises in the east and sets in the north. It probably isn't possible to predict day lengths for all time, but it would be believable to be able to forecast out a few years. [Answer] **Obliquity Oscillation** Not all days on Earth are created equal. The days are longer in the summer and shorter in the winter. The reason for this is simple - Earth spins on an axis which is an average of 23.4 degrees. The measurement for this axis is the difference between the rotational plane of the Earth around the Sun, and the Earth's rotation. This is called obliquity. And the obliquity oscillates. Not a lot on Earth, and very gradually, a very small amount to the point that you barely notice it. This is because it's been stabilize by, among other things, the moon. But it could be much greater, and happen faster. If it does, then it's possible for locations on said planet to be pulled above or below the tilt and thus act as the arctic circle might - have days of sunlight, then days of darkness, and when the obliquity oscillation doesn't pull it in and effect it, normal days. Of course, there are problems. This would only affect certain areas of the planet, it'd be hard to get to the equator, a destabilized obliquity would play havoc with the weather, and it would take a nightmare's worth of calculations to figure out how exactly it might work. But it's a thought. [Answer] **Hyperion, Saturn's moon, has neither a predictable length of day nor direction of rotation** Hyperion, one of Saturn's moons, fills some of your requirements. But it has a number of weird factors. See <https://en.wikipedia.org/wiki/Hyperion_(moon)> and <https://www.space.com/20770-hyperion-moon.html> . Elongated shape, so that the ends are much farther from the center than the lowlands. Low mass, such that a catapult could fling you off, especially if you started at one of the ends. Very odd composition, probably water ice and organics, with a very high percentage of empty bubble spaces, like Styrofoam. Elongated orbit around Saturn, synced with the larger moon Titan. Strong electric charge. Note that the orbit is stable in a 3:4 relationship with the larger moon Titan. So its position in space is well-predicted, but the orientation is not. [Answer] You can achieve what you want with [Axial Precession](https://en.wikipedia.org/wiki/Axial_precession). This actually happens here on Earth, although at a very slow rate (26,000 years for one rotation, this is believed to be a contributing factor to ice ages here). If your planet or moon had a faster, more erratic axial precession (say on the rate of 1 or 2 per year or 1 every 2 years, with a large tilt angle), or even better - multiple (3 or more) axis of rotation you could have highly variable day/night lengths. This would lead to some very erratic season as well. [Answer] Something like that, though less extreme, could be possible with a fairly eccentric orbit. Let's say the eccentricity is 1/3, which means that aphelion (the farthest distance from the sun) is twice the perihelion (closest distance). From Kepler's Laws we then have that the orbital speed at perihelion is twice that at aphelion. As an approximation, let us assume that the orbital velocity is equal to the perihelion velocity for the entire quarter orbit nearest the sun (which is fairly close to the truth) and let us say that this quarter orbit corresponds to the longest day, from sunrise to sunset, or 48 hours. The planet then must make three-quarters of a full rotation during this quarter orbit, meaning that the rotation period of the planet is 64 hours. At the aphelion, the planet would need roughly 96 hours to complete a quarter orbit (again as a close first approximation). This is one and a half rotation corresponding to to one and a quarter day/night cycle. A day is hence appromimately 38.4 hours. This is less extreme than what you ask for, but a more eccentric orbit would imply even more extreme temperature differences than here, where the planet receives one-quarter the sunlight at aphelion than at perihelion. A very thick atmosphere could comnpensate for this, but not much more. Another thing is that the total orbital period of the planet here is only 288 hours, or 12 Earth days. This implies a very cold sun, most likely a red dwarf. If you don't want that, this is not the solution for you. ]
[Question] [ The space borne planetary invasion force is a staple of many Sci-fi genres and most space invasions face the need to destroy some, or all, ground based infrastructure from orbit in order to take over a world. One of the things that often puzzles me is the depiction of lasers or particle beams for targeted ground attacks. These weapons would seem to tend to be dispersed or deflected by atmospheric gases and planetary magnetic fields. Assuming: * that orbital dropped munitions are at least as accurate as modern smart bombs. * that you have access to "dialable damage" kinetic weapons for attacking ground side infrastructure. * that you want the planet you've gone to the trouble of invading largely intact, so no [cobalt bombs](https://en.wikipedia.org/wiki/Cobalt_bomb) or other long-term area-denial weapons. * that these weapons, while extremely useful for hammering planetary targets, are too slow moving for ship-to-ship combat and as such are not used as combat vessels' primary weapons. * that such weapons are not excessively large and can be mounted on/carried by warships without compromising their primary mission capability. * that planetary bombardment is rare in other circumstances but almost always necessary to support invasion forces. **For what practical reasons would weapon systems which are more suited to ship-to-ship combat be used in this planetary mass destruction role when they appear to suffer issues of accuracy and loss of power due to atmospheric effects and possibly cause excessive/secondary damage effects as a result of either [heat bloom](https://en.wikipedia.org/wiki/Thermal_blooming) or, as in the case of nuclear or particle beam weapons, the nature of their operation?** [Answer] # Because they are the most efficient way to deal damage to your specific target An (arguably) non-kinetic bombardment weapon would be an antimatter beam, which is a great opportunity to commit genocide..., no!!! cleanse heresy, no!!! strategically secure the target yes!!!. You did say that the planet should be captured intact, but there are many levels of intact. Especially if you are dealing with a hostile biosphere or some biological enemy like the Tyranids or the Zerg, keeping the atmospere at a toasty 500 C for a few days before landing should help. Antimatter beams would probably be best for this, but lasers whose energy will be absorbed by the atmosphere will do great as well. # Because Ammunition is more (mass) expensive than reactor fuel and radiator time Remember the rocket equation? Everyone in space does. Maybe it is just more efficient to carry around the reactor fuel to power the energy weapons than it is to carry missiles and uranium enriched tungsten speers. While in a space battle radiator time is a valuable resource, during a bombardment taking care of heat is simple. # Kinetic weapons are energy weapons Maybe your military avoids many issues (waste heat management) shipboard energy weapons bring with them and uses missiles with nuke-pumped-x-ray-laser or casba howitzer warheads (nuke-pumped particle beams). For planetside bombardment they are used as an energy and kinetic weapon. They fire the energy-weapon component to blind the target and hit it then with the high speed shrapnel the missiles husk has turned into. # Because energy weapons are what the vessels carry This is based on the rocket equation again. Every gram counts on a spacecraft. The military may have access to decent kinetic weapons, but if they are as you say useless in vessel to vessel combat (I do not think the are, but it's your universe) carrying them around is simply too costly delta-vee wise. # The real reason why popular media shows this Hollywood has no clue about Hardish Sci-Fi. **Lasers look cool and cool weapons are better war-maschines than realistic ones.** Visually colourful laser beams are more impressive and easier to produce than depicting missiles and kinetic slugs. Star Wars and Star Trek did it and have influenced most subsequent Sci-Fi. Audiences and lazy writers know it and love it and thus a vicious cycle ensues. [Answer] **Economies of scale matter on warships too** If you look at naval vessels throughout history, they have always tended to evolve towards specialization in weaponry. The more different kinds of weapons you have, the more complicated your maintenance, logistics, and even design and construction of your ship get. This is why it's very rare to see a warship of almost any era with multiple primary weapons systems. The best designs pick one thing and do it as thoroughly as possible. In response to your question, the simplest explanation is that the PRIMARY role of the space battleships is destroying other space-based defenses and that is best accomplished with directed energy weapons. Once that has been accomplished, the actual orbital bombardment is a secondary task, and the weapons you're using only have to be 'good enough'. Adding specialized planetary bombardment weaponry would make the ships LESS capable at defeating the space-based defenses, so you're better off specializing your ships for space combat and accepting that your bombardment is going to be a bit less effective. **EDIT:** > > Assume... that such weapons are not excessively large and can be > mounted on/carried by warships without compromising their primary > mission capability. > > > I'm going to challenge this item in your post because you can't have a realistic discussion about military engineering with an assumption like this. Nothing is free in engineering, and there's no such thing as a weapons system that doesn't contribute to the primary mission of the platform that DOESN'T compromise the primary mission capability to some degree. It's always a question of 'how much' does it compromise that mission capability. Remember we're not JUST talking about mass, or power consumption, or any of those things. Adding extra weapons makes the ship more expensive. It makes it more complicated. It means you're mounting this kinetic weapons system INSTEAD of something else that WOULD contribute to the primary mission and that is never beneficial. Here, again, if the primary energy weapons systems on the warships are capable of performing the secondary planetary bombardment mission adequately, it doesn't really matter if it's a small compromise versus a large one to mount a separate kinetic bombardment system, it's still unwelcome and makes the ship less effective than it could be. [Answer] **Particle beams are a nice clean way to eradicate life forms.** Neutrons are uncharged particles and so will not be blocked by a planetary electromagnetic field or shields relying on that sort of thing. This is true for heavier particles too. In this question [What subatomic particle is best for a particle accelerator gun?](https://worldbuilding.stackexchange.com/questions/101554/what-subatomic-particle-is-best-for-a-particle-accelerator-gun/101590#101590) I figured that radon particles would be the best for delivering energy that would penetrate intervening matter (here atmosphere) and drop off the energy within a calculable area (where your enemies and their pets live). The neutron bomb claimed some fame because this type of radiation would supposedly kill everything but leave buildings, weapons, sports cars intact. Rods from god do not leave infrastructure intact. If you want to reclaim your holy sites, or take over the phlogiston mines, or drive around in sweet enemy sports cars you can't turn them into craters. Uncharged particle radiation would be a fine way to eradicate life from the area. A beam instead of a bomb also reduces residual contamination from radionuclides generated in the explosion. Note: you might need to give the particles time to work. They probably will not kill everyone outright but should within the next couple of weeks. [Answer] Kinetic weapons can be intercepted. If you have lasers capable enough to engage in ship-to-ship warfare and punch through atmospheres to destroy ground installations then surely those ground installations have lasers capable of destroying falling rocks. What would be the point of constructing planetary defenses if they weren’t capable, at the very least, of defending against the most effective and economical method of attack? Lasers and particle beams, on the other hand, cannot be actively intercepted. ]
[Question] [ For visual reference: [![enter image description here](https://i.stack.imgur.com/6s9w3.jpg)](https://i.stack.imgur.com/6s9w3.jpg) Apes are visual species who rely more on their eyesight than any of the other senses. As a result, they see the world in three shades of color, whereas other mammals see in one or two shades. That is how we can see the tiger as orange or the jaguar as a kind of golden yellow. In an alternate Earth, could apes (including humans) be naturally patterned like the big cats rather than as a result of artificial genetic engineering or disorder? [Answer] They already are. And that includes us humans. You just can't see it. Our patterns are called [Blaschko's lines](https://en.wikipedia.org/wiki/Blaschko%27s_lines). They exist because when we are embryos, the cells that will form our skin migrate in waves to where they will be. In almost every human the cells are all genetically identical, but if some of the first cells mutate, or in the case of chimeric people, there will be different populations of cells in the skin. In such cases, should a condition affect only one population of the cells or affect each population differently, the patterns may become visible. They look like this: ![Patterned human skin](https://i.stack.imgur.com/Degjq.jpg) ![More patterned human skin](https://i.stack.imgur.com/KrMnP.jpg) ![Yet more patterned human skin](https://i.stack.imgur.com/WsCti.jpg) Notice that this is not the same as vitiligo. It is also possible for someone to have two skin cell lineages and have no visible patterns - under visible light. Sometimes these patterns are only visible in UV. You can try and find out if you are chimeric by exposing yourself to a UV lamp (the odds are pretty low). If you wish for hominids in your world to have such patterns without the need for mutations or chimerism, have the skin pigmentation genes to activate just like most genes in the X chromossome do. In every cis woman's cells, one of the X chromossomes is shut down. The one that is shut is decided at random early during embryo stages, so there are whole patches of skin cells grouped together with only her mother's or her father's X chromossome activated. If you want both sexes to display this characteristic, either have the genes for it outside the X chromossome, or have them in the X **and also** in the combining regions of the Y. Last but not least, remember that just as genes can affect skin as described above, they can also affect hair and fur. So you can decide whether you wish for the patterns to exist only for the skin, for the coat, or for both. [Answer] Yes. [![marmoset](https://i.stack.imgur.com/wMFXQ.jpg)](https://i.stack.imgur.com/wMFXQ.jpg) I think this is a white headed marmoset. It has 3 color stripes in the body and a pretty striking face. Of the images in your montage the cloud leopard is the closest to the marmoset pattern-wise and also habitat wise. Other mammals from very different lineages have patterned coats - dogs, zebras, tapirs, mongooses etc. Marmosets are primates but not too close to great apes. The great apes are uniformly colored I think (excepting when they go gray). But hair color has a lot of evolutionary flex and I think any fur bearing mammal could potentially have a patterned coat. The problem with humans is that we have such puny coats. You would first need your humans to muster up some fur. Or you could have fur in a pattern - human body hair is definitely in a nonuniform pattern. Or you could have the skin itself be different shades - dark skinned people often have light skin palms, and light skinned people can have darker pubic skin. There is no reason the skin could not have a pattern. For evolution to select this of course the skin pattern would have to improve fitness somehow - probably because it was visible. ]
[Question] [ [My dragon](http://worldbuilding.stackexchange.com/questions/137872/the-nuclear-dragon) So to give a quick description, this is a 2 mile long, nuclear powered dragon of doom. I think I’ll going with a fission/fusion hybrid creature for this beast. Another piece of relevant information is that all dragons in this universe utilize pretty much all metals as structural substrates. In fact, barring very advanced technology, their corpses are the only source of dragon steel. So the idea here is that the dragon uses metals in its sinuses and other resonance chambers to increase the variety of sounds it can make, along with the volume of the sounds. I had also thought about the possibility of the dragon using partially metallic vocal chords. However, the question is **why?** What could they use this vast array of sounds in varying pitches and volumes for? Most intelligent creatures can get by with making just a few noises, so why would these dragons need such a vast array of sounds? [Answer] **These dragons make music.** Humans are intelligent creatures and we make a bafflingly large variety of sounds. When I listen to popular music there are all sorts of sounds I cannot identify. Heck even the Beatles "Across the Universe" has a lot of weird sounds - try playing it on ukulele and it is so nondense and thin. Anyway: so too the dragon (not the ukulele, the variety). These dragons are enthralled by music in the broadest sense - found, imitated and invented sounds which they make up as they go. Like whales they sing constantly but unlike whales they sing on many levels and with many tones at a time. Do the other nuclear dragons hear them? Possibly. These things are unlike other life forms, and may have sensory modalities beyond those of normal creatures. [Answer] Your Dragons communicate largely using [infrasound](https://en.wikipedia.org/wiki/Infrasound) as a means to transmit across long distances. Similarly to Elephants, Hippopotamuses, Rhinoceroses, and even Alligators, these organisms find utility in the ability to communicate with others of their species over very long distances, especially given that as a 2 mile scale creature they require rather large territories. [Answer] **Your dragons are self-sustaining MIDIs and synthesizers.** They sound like a slightly artificial version of *any* noise on the planet. All human languages, the output of all instruments, all birds, all insects, all mammals, all frequencies. They can re-create the sounds of a thunderstorm, a volcano, or the tiny scrunch of earthworms as they push through the light crust of soil formed by the hot after the rain. Why would they want or need such abilities? * **Amusement.** How lonely must your dragons be? * **Communication with other dragons.** They can save the sounds they make (tons of space, materials, and energy to work with) and transmit them to others over vast distances. * **Bringing animals to them** for amusement, food, or to perform tasks. * **Keeping animals away from them.** * **Direct communication with other intelligent lifeforms.** * **Changing landscapes over time.** They can send out noises that cause landslides, crack the ground, perhaps even trigger small earthquakes. This can lead to places for water collection, or dispersion, areas for plant growth of different kinds, and so on. [Answer] **Active sensor arrays** Being fusion powered your dragons have a particular appetite for hydrogen bearing matter. Using sophisticated multi-spectrum sound analysis they can scan their immediate environment for the resonance signatures of certain hydrogen-rich organics and minerals, much like EM spectral analysis but at a macro level. The sound is also used for motion detection and as a crude form of X-ray scanning hollow bodies such as buildings and caves. ]
[Question] [ Tools available would be wire, bricks, hammers, a hack saw, a pair of compound snips, and flex glue. As well as the intact body of the car itself. Assume you find the tools inside or easily within view. The context is that the individual crafting the equipment has some technical know-how but lacks the means to more effectively process available materials. Fire cannot be used, either because the individual is not a blacksmith or because it would draw unwanted attention. The car, manufactured in 1997, is also unusable as a motor vehicle due to circumstances beyond their control. A description of the method and resulting weapon or armour, as well as confirmation of this being plausible are desired. [Answer] There are strategies how to use a car as weapon or armor, but none of them look like a medieval knight in armor. The outer metal sheets are much too thin to be effective. # Protect your body If you want to surround your body with metal plates from a car, you need to use several layers (I think 3 layers as a minimum or your bending and ripping armor might injure you more than the initial blow). Even in 1997 car manufacturers wanted their cars to be inexpensive and lightweight, so they used the thinnest reasonably possible metal sheets. The tires are far more effective as armor, but heavy and cumbersome. You need to cut (or saw) the sides away so only the tread remains. Tires have a steel mesh incorporated into the tread that - in combination with the rubber - should withstand hard blows and maybe even stop arrows. I propose padding the inside with material from the seats or doors and maybe add a layer of sheet metal on the outside to distribute the force of impacts to a wider area, decreasing the risk of bone fractures. Cut the tires into a form like a bulletproof vest, then use strips of seat belts and glue to hold the thing together. If the glue doesn't stick, find something like a nail and use it to push the ends of the belts through the tires with a hammer and then tie them off. # Protect your life Take that first aid kit with you! No matter what, you want that first aid kit. # Make a weapon The problem with a short sword is its shortness. The risk of being injured gets higher, the closer your enemy gets to you. Is there a crowbar or a long handle of a car jack in the car? There you have a very simple weapon with a range comparable to a short sword. For an untrained person, I would suggest finding something that resembles a spear. You don't want to shape the outer metal plate into a spear unless you want it to be one-use-only. It will bent much too fast. Unfortunately, nothing in a car comes to my mind that could be used as a spear shaft. If there's a young tree with a straight stem nearby, cut that down and use it as a shaft. To make a suitable spear-point, cars quite frequently use cast steel for wishbones which (with a lot of hacksawing) could be made into a very serviceable spearhead. (Thanks to Ynneadwraith for the suggestion) Instead you could tie a heavy object to the end of a seat belt and use that as weapon (like a ball-and-chain-flail). Are there glass bottles lying around? (I hate people who never clean their car) Fill them with fuel, oil or pure de-icer, stuff some fabric from the seats into the opening and have your lighter at hand. You now have a molotov cocktail. If you don't have a lighter, carefully open the car's battery and fill the bottles with acid. Is there a fire extinguisher in the car? That can be utilized as a weapon, too. With some MacGyvering you could build a rudimentary cannon and load it with the remains of the wind shield or some batery acid. I'm not sure the fire extinguisher has enough pressure to blow glass shards very far, but you could *very carefully* extract an airbag and use that to propel your projectiles. (Airbags are dangerous and an untrained person could kill themselves by accidently activating one. They do pack a punch!) You could also build a slingshot with a V-belt and maybe something like the headrest of a seat. Glue a little bowl-shaped piece of plastic to the belt and load it with the shards of a window. I'm sure with enough time and the right incentive, you could find many more ways to utilize a car as weapon. But do you have to? # Be a Magician If the story is about a man landing in the past or another dimension and facing the natives of this area, he might fare better by pretending to have macical powers. Things like a torchlight, fire extinguisher, space blanket or the car's horn would seem pretty magical to them. If you aren't strong, you better be smart. [Answer] A hacksaw would take time but would do the job with care if you only had one blade. If you had more you could work faster. Car sheet metal is already ideal for armour because it can be shaped with the tools available. It just needs to be cut to shape and then could be hammered to fit the body and wired to hold together, double up the critical parts. So chest and backplate, greaves, thigh guards, even a helmet if you had the time. Pad whatever needs padding using the seat material. You don't need heat at all. You could make forearm guards, but since you're using a shortsword, probably better to fashion a shield. Hammer over a piece of metal, but first cut the grip and forearm brace and shape them on the side which will be inner. Bonnet and boot are your best options, the steel there is usually thicker and has existing reinforcement. For your sword you could use plate as well, just hammer it over into a fold and sharpen one end against concrete or hacksaw it on an angle to produce a sharp edge (or both), and wrap the handle part so you don't cut yourself. Would make a robust ,serviceable shortsword. This is mild steel though, ok for a fight or three, but not longterm against people with stronger weapons. Shoulder/neck guards and other important parts you could use two thicknesses of plate with some seat material glued between. That would give you 2.4 mm of steel which is more than medieval plate armour. If you had the shield you wouldn't need much else and weight will be a factor. All this is just time and elbow grease. There are lots of better weapons that could be made from car parts though if you really had a lot of time. Even the snips broken apart would make a good spear point. However the Romans routinely took on all comers with shields and shortswords. The snips blade, some plate and a shaft made from exhaust pipe would make a couple of pilum which would give you a big advantage against most individuals. Throw the pilum then engage with shortsword and shield. [Answer] Creating an improvised weapon from the remains of a car could be as easy as recovering the jack handle from the trunk. In many cases, it can also make a good improvised crowbar or be used as a general purpose tool as well as a weapon. [![enter image description here](https://i.stack.imgur.com/d5iyf.jpg)](https://i.stack.imgur.com/d5iyf.jpg) *Jack handle/lug wrench combo. The sharp screwdriver like point at one end can be used to stab enemies or pry open doors and boxes* Armour is a much trickier topic. Many people believe all you need is some solid metal to stop a blow, but this ignores the fact forces can be transmitted through the armour plate. In the late middle ages, smashing weapons like hammers and maces became common because well made suits of plate could deflect sword strikes and thrusts from spears and other polearms. Since we are limited to the materials of a car, you will need the following: A *gambison*, or padded jacket to absorb and distribute the force of blows against your person. A well made *gambison* is good protection in of itself for things like slashing attacks. The fabric covers of the seat and the padding within could be repurposed with some creative sewing to make a *gambison* for you to wear. [![enter image description here](https://i.stack.imgur.com/E4NHq.jpg)](https://i.stack.imgur.com/E4NHq.jpg) *A nice example of a gambison* The next level would be some sort of outer protection. As noted, the sheet metal of modern cars is rather thin, and indeed some cars derive a lot of their strength from the way the metal is folded (the way a creased sheet of paper can be strong in some directions). Rather than try to make large articulating plates, a task which needed highly skilled professionals in the Middle Ages, we might make do with Brigandine armor jacket. Luckily for you, you can scavenge an old car lot and find a car with leather seats (or if you are stuck with the one car, peel off the vinyl roof cover), then cut small strips of steel and attach them to the jacket. This provides a flexible outer surface that will allow you to move, yet have the hard surface to deflect blows and stop (or at least minimize) stabbing attacks. [![enter image description here](https://i.stack.imgur.com/7P3nA.jpg)](https://i.stack.imgur.com/7P3nA.jpg) *Brigandine armor* To save on weight, you will likely just make the Brigandine more like a vest, and trust the padding on the *Gambison* to protect your arms. Making protection for the arms and legs is optional, you will need to trade the extra wight and reduction in speed and mobility against the extra protection. As well, you will need to create some sort of harness of straps and buckles to keep all the extra pieces attached to you *without shifting around*. This YouTube video shows the process of putting on a full harness, but pay attention to the various straps and buckles needed: <https://www.youtube.com/watch?v=k24y_ZmxRHg> And another video: <https://www.youtube.com/watch?v=zGl_UXc9HIE> The Helmet, assuming you go that route, is going to be the most complex piece. You need something which is simultaneously light, form fitting, allows excellent vision and hearing, protects your eyes and ears, and has a padding and suspension system to allow air to circulate around your head, absorb blows and prevent the helmet from shifting around on your head. Maybe you should take your chances.... So you can see scavenging a car (or anything else, for that matter) isn't the real issue in creating arms and armour, rather, armour requires a great deal of work to manufacture so that you have protection that is lightweight, provides mobility and still gives protection. [Answer] As armor, it depends on what level of protection you are looking for. Against other improvised blades, it is definitely better than nothing, maybe even crudely made stabbing implements. Against a sturdy spear or a heavy blunt object, not so much (I've torn apart a '60's (I think) era Monte Carlo with nothing more than a sledge hammer.... very therapeutic.) Under a heavy blow, the steal will just peal away. The sturdier frame metal would be too difficult to form using the tools you described and would be very heavy. As a weapon, again, the sheet metal can make an excellent edged weapon for minor work. Best for a tool. As a combat weapon, not so much, especially if the opponent is using improvised armor. The metal will just deform too easily. Others have mentioned there are plenty of other weapons that can be made from this car that is not a cutting tool. Blunt weapons would be a better option. ]
[Question] [ I have a species that is a descendant of modern humans, but containing superior bioengineered organs. One of these organs would be a small heart-like organ inside the head. This heart connects with the lungs, and would keep the brain alive for a period of time after the main heart failed. My question is: would a heart located much closer to the brain keep the organism conscious for longer than without in situations where many Gs are being exerted on the organism, such as when performing maneuvers in a fighter jets? [Answer] The issue with the brain during high g-force maneuvers is that less or no blood reaching the brain means less or no oxygen supplying the neurons, leading to loss of consciousness. While it is true that the heart pumps the blood, it's the lungs that replenish it with oxygen. During a high g-force maneuver pulling the blood downwards and away from the head, the heart of your species would have to suck it even more against the gravity gradient. When you study pumps at University you are always told that while pumping liquid pushing is way better than sucking it: beyond a certain sucking pressure, you induce cavitation, which severely damages the pipes and/or the pump. In this case cavitation in the bloodstream would be dangerous for the veins and/or the heart, with also the possible formation of thrombosis. All in all, I think this is a worse implementation than our present model. [Answer] The tendency to want to faint when being subjected to high Gs results in lack of oxygen to the brain caused by increased difficulty for the body to pump the blood to the brain. So if there were a tiny heart in the brain, it would pull blood and your normal heart would push blood, adding a little bit extra force in situations where pumping up blood is more difficult such as when being subjected to high Gs. So yes, such a person would be able to withstand higher Gs. How many more Gs depends entirely on the force of the tiny heart in the brain, but the amount of Gs which can be withstood is likely going to be proportional to the amount of extra force the tiny heart can provide. Consider also that the pump of the heart and of the heart in the brain is likely going to be synchronous, or otherwise you'd stress the arteries leading to the brain too much. Also in a somewhat unrelated note, the arteries leading to the brain would still likely have to be much thicker than what they are now, so you should keep that in mind (otherwise something as simple as a heart murmur would risk serious pressure on the artery leading to the brain, which over time could be fatal should it weaken and break). [Answer] Cool Idea, I'd have to go with a definately yes - but it's going to be hellishly complicated getting the blood in and out. You're going to have to either go with a completely separate redundant circulatory system connecting this heart with the brain, or figure out some other method of stopping the 2 hearts from competing. Mind you, if the Doctor can do it then I guess so can your metahumans... However you do achieve it - I definately think it will help your people handle high Gforces better. The other problem I suspect you'd run into is the heart has a lot of movement (all that pumping! Ker-thump ker-thump ker-thump...) - and the brain isn't too happy with being bashed about... [Answer] A possible solution, given that we're talking about pretty advanced bioengineering here. Why not just go whole hog and **get rid of the heart entirely**? Basically, the heart is a kind of invagination of the great vessels with powerful musculature and some electric stimulation to keep it ticking regular. Rather than a single, central pump with a sub-station pump in the head, engineer a system where all the vessels (from the aorta ~ vena cava on down to the main branches and lesser vessels) pump peristaltically? Combined with a system of back-flow reflux valves (such as already exist in the veins) you should be able to achieve a continuous & active flow of blood throughout the system. I imagine that the check valves, especially those in the head and neck will help reduce or eliminate the effects of gravity 'sucking' the blood away from the brain. Also, the peristalsis will keep the blood flowing continuously and thus perfuse the brain. Obviously the bioengineers would be using a type of cardiac muscle that, like the muscles of the heart, do not tire the way skeletal muscle does. Just like a heart, it won't do for the system to rest or shut down untimely! The long and short of this system is that you have "lots of little tiny hearts" in the brain (and everywhere else)! [Answer] [Move the brain to the heart instead.](https://www.youtube.com/watch?v=sbRom1Rz8OA) Strong G-forces push blood to the extremeties of the body. That means the head or the feet depending on whether you're swooping upwards or downwards. Both are bad for the brain. The brain would be safer if located in the middle of the body. This also means an injured heart sends blood to the brain before everything else. If the heart has completely failed the chest brain will not save you. But if it is flagging the chest brain will last longer then the head brain. [Answer] Loss of consciousness from high G-forces is an issue of blood being pushed out of the brain, into blood vessels lower into the body. This is possible because blood vessels and their surrounding tissues are flexible and do, to some extend, expand and contract depending on pressure inside. If you experience high G-forces, a rather large pressure difference builds along your body. G-force roughly translates to +x pressure/length, so the longer blood can flow more or less freely along the direction of said force, the greater the effect. A second miniature heart inside the brain won't have any effect on this, the blood will still drain according to G-forces. A more realistic solution, I think, would be a system of blood vessels designed to work against pressure differentials, for example by a) blood vessel walls being able to stiffen/relax dynamically in reaction to G-forces or b) muscular "valves" that can temporarily restrict blood flow while high G-forces are acting. The former solution would allow for resistance against permanent high G-forces but is more complex biomechanically, the second will prolong the time you could spend at high G (but you might eventually still pass out due to restricted blood flow). ]
[Question] [ So, I’m designing an alien race, called the \_\_\_\_\_\_\_\_\_\_\_. They live on planet \_\_\_\_\_\_\_\_. My question is, what type of biology could make creature get effects similar to alcohol, but with sugar? [Answer] **Your species are type 1 diabetics.** People with type 1 diabetes do not make insulin. Ingested sugar causes an uncontrolled rise in blood sugar. This can lead to [diabetic ketoacidosis](https://en.wikipedia.org/wiki/Diabetic_ketoacidosis). Many of the symptoms of DKA overlap with those of alcohol intoxication. Police pulling over an impaired driver can have difficulty telling the two apart. <https://www.lextalk.com/b/lextalk_blog/archive/2016/01/11/dui-amp-diabetics.aspx> > > Drivers who are suffering from a diabetic incident and have an excess > of ketones in their system, also known as ketosis, may appear to be > under the influence of alcohol. Drivers experiencing ketosis will > often emit a sweet smell on their breath that police officers may > confuse with alcohol. These drivers also may appear to be sluggish, > confused and lackadaisical, which may be confused for alcohol or drug > impairment. These drivers will be asked to complete various field > sobriety tests and may have problems with coordination or balance as a > result of ketosis or diabetic ketoacidosis. As a result, the driver > may be arrested on suspicion of driving under the influence of alcohol > as a result of the “physical indicia of intoxication” observed by the > investigating officer. > > > In addition to the cognitive / psychologic effects (sleepy / aggressive / silly etc) people with DKA also get plain ill, which you seem to be looking for (throwing up, passing out etc). Maybe your species evolved in a circumstance where there were barely any carbohydrate foodstuffs and so they did not need insulin. Maybe in their new circumstances they all developed type 1 diabetes. For a story, a problem with DKA is that in humans with type 1 diabetes DKA can kill and so if you are going to play drunkenness for laughs that does not seem right. But you can riff off of the DKA idea and give the aliens some failsafe insulin-like hormone - some sort of inefficient substance that begrudgingly and slowly cleans up the mess after the sugared-up aliens stagger around in DKA for a while; sort of like alcohol dehydrogenase does for us. Animals like horses with loads of alcohol dehydrogenase are immune to getting drunk. As regards alcohol we are to horses what your aliens are to us as regards sugar. --- Thinking a little further, you could hand wave your alien DKA such that the serious dehydration and electrolyte abnormalities only happen with the worst cases, but that excess production of acetone happens a lot. DKA is a mix of being sick and intoxicated, and the acetone is responsible for a lot of the intoxication - symptoms from acetone excess are similar to those of ethanol excess. So you sugar drunk aliens would reek of nail polish remover and otherwise just act drunk. [Answer] Well, as pojo-guy pointed out, this actually can happen with an excess of yeast in the body and a relative dearth of the enyzyme responsible for breaking down alcohol (alcohol dehydrogenase). It would also theoretically be possible if the enzymes—blanking on their names at the minute—responsible for breaking down the two other poisons that alcohol dehydrogenase converts alcohol into were missing, and a body couldn't make the jump to the terminal glucose-water mixture. That said, if you just mean "intoxicated" in an alcohol-like way, there are a lot of other ways to do it. Alcohol technically refers to any chemical that contains a hydroxyl bound to carbon; and most of them aren't digestible at all by humans, but have a similar (and potentially lethal) toxicology and definitively a similar chemistry. I don't like the idea of depending on yeast to form an alcohol, when we're obviously dealing with another planet; so let's look at the chemistry of fermentation. Assuming we're talking about sucrose sugar, the first thing yeast does is cleave it into fructose and glucose. Once that's done, the glucose is broken down into pyruvate and a phosphate; the pyruvate molecule then gets a hydrogen ion tacked onto it and the enzyme pyruvate decarboxylase takes a whack at it, and you end up with ethanol, and a whole bunch of other crap. The issue is, this is relatively one-way; your organism would likely still need a symbiotic relationship with another organism that does this in order to produce the alcohol. In turning glucose into alcohol, and alcohol back into glucose, you would get zero chemical energy gain. Many of the effects of drunkenness are also derived from our attempt to metabolize it. Sugar is a simple and relatively harmless carbohydrate. So I would say, have your microbial symbiote (like mitochondria for mammals) digest the sugar and produce alcohol in a manner similar to how yeast does, and the host deal with the alcohol enzymes. [Answer] Your aliens are [Ruminants](https://en.wikipedia.org/wiki/Ruminant). Then you can do the whole alcohol making process in house. For sugars to ferment you need to have a couple of things: sugar, a solvent (usually water) and yeast. Temperature influences the speed of the fermentation. The solvent is needed for the yeast to be able to work. Plain sugar (or honey) and yeast will not ferment. So yea, when a ruminant, like a deer, eats sugars and yeast they can get drunk on it. [Apples](https://news.nationalgeographic.com/2015/11/151121-animals-science-drunk-insects-mammals-drinking/) will do so. ]
[Question] [ Given a woman who can make volumes of air into solid, impenetrable barriers, how expensive of a modern military force could such a person defeat if her power has these conditions: * Her effect is basically forcing the air molecules / atoms / ions / whatever, to not move. So she can't filter air or anything. * "Air" being a shorthand for any gas. * The altered volumes of air stay where they're placed, relative to the Earth. * The altered volumes have no visible changes, but only visible light can pass through or affect the volumes. * When she decides to create a volume, it has to be in her sight, so if her vision is hindered, it's a bit harder, and it doesn't work in the dark. * Created volumes can be instantaneously expand and shrunk, regardless of vision, in any direction she wishes, so long as they follow the other constraints, and is expanding into open air. If it would fail, she could still try, and will know if it fails, but doesn't know more than it failing because of intersecting an object. * She can maintain her volumes indefinitely, even through sleeping, but not if rendered unconscious through sleeping gas or other methods. * The total volume altered must be no larger than 10m³, otherwise, she has to revert some areas to keep her changed volumes, under that limit. * Any individual section has a thickness of at least 1mm. * Anything hitting the "forcefield" has no effect. It's just magically stopped, you can't strain her by hitting the field too much, it doesn't turn all kinetic energy into visible light, nothing, just stopped. The forces are surprised by each other, with the military force initially thinking she's a normal human, and hopefully, they figure out that she's making the barriers. Inexplicably, hostilities start in the morning, on an open, grassy plain, in calm weather. Behind each party are mountains. She has no allies. Hostilities stop once one side is dead or incapacitated. The forces start one mile apart. The superpowered woman can use weaponry they acquire from defeating the forces against her. Technology is constrained to that which is available to 2016 America. --- **So, how expensive must that army be, in order to defeat a woman with such powers?** **Expense is calculated in the cost of equipment and the amount of training required to use that equipment to the required skill level** [Answer] Put simply, this woman is effectively invincible, because of the ability to sleep with her impenetrable shield up. With 10 cubic meters of potential volume, this woman can create an indestructible cube about 40 meters on each side (made out of one millimeter sized cubes). Given that she can effectively move this indestructible cube by growing and shrinking the leading edge, she can move wherever she wants with impunity. If she was skilled enough, she could even do that while operating a motor vehicle. To refresh her air supply, she can create a second, smaller cube (after shrinking the first one) wait inside there and then drop the outer cube, she is then free to move somewhere with fresh air. Given that she has 64 thousand cubic meters of air (or 64 million liters) to work with, she has to do this at most once a day, but probably far less. If it weren't for the constraints of the deathmatch, this woman would probably be better off just going about her life like nothing was different. Given that she's set on mass murder, it's simply a question of walking towards the nearest target and suffocating them. Tanks and planes are no issue, as she is impervious to their assault, and if she sees the airplane she can just put an invisible wall in front of it. As for the tank, she can just wrap the air inlet valve in her magic shield and choke the engine out, or if she wants to kill the crew, just wrap the whole thing up tight and wait it out. If she shrinks her shield down she can catch a whole platoon of tanks or more and choke out both them and their occupants, very quickly if she makes sure the air intake for the engine can pull air from the crew. She is effectively immune to any quantity of conventional weapons, so the answer to your question, assuming no WMDs are used, is infinity dollars. Her only weaknesses are that she must manipulate the air about her without being able to move her invince-o-walls and the fact that visible light can pass through. Not being able to move her walls except by growing and shrinking them, means that a determined opponent could flood the area with airborne biological or chemical weapons. In order to move she would have to bring some of those agents into her space, which would result in her death. As a cost estimate [this article](http://warincontext.org/2013/12/11/how-easy-is-it-to-make-sarin/) suggest that is costs 30 million dollars to create a production facility, so we'll just double it and say that's enough Sarin gas to keep her surrounded in a deadly cloud long enough to suffocate. So that's 60 million dollars. We'll ignore what it will cost in human lives to determine this weakness or simply make them mad enough to try it, but that could potentially double the cost again, depending on factors. The other option is a nuclear weapon, at point-blank range, so the visible light is strong enough to disable (or vaporize) the intended target. [This article](https://fpif.org/much-nuclear-weapon-actually-cost/) suggests that a nuclear weapon can be produced as cheaply as 350 thousand dollars (not counting overhead or delivery method, most likely), making it the affordable choice. To ensure the weapon is maximally effective and delivering nothing but visible light, it will be helpful if we can get our super murderer to wrap it up in her invincible force field. That will trap the blast wave and other forms of radiation, bouncing them back in to produce more light in the visual spectrum. Perhaps the bomb can be placed inside a mock tank of some kind. A timer or suicide crew will be necessary to detonate the weapon at the right time, or some form of laser communicator. All in all, this woman would make for a hell of a villain. [Answer] **There are two questions, the largest army she could defeat and the smallest army that could defeat her.** The size of the army she could defeat is practically unlimited, though her powers are largely defensive, they can be used as an aggressive defence. She can't lift a vehicle, but any vehicle that tries to move can be ramped into the air and dropped or inverted. She doesn't have a weapon but she can block barrels, suffocate individuals or otherwise immobilise any attacker all while maintaining a perfect shield. She can fix blades of air as traps for people and vehicles. It's going to be nasty and bloody and all it takes is time. It seems she could even drop the air pressure in a region to effectively zero. All the while those fancy expensive bombs and planes and missiles are useless against her. **If they don't know what's going on, they're all going to die.** *She is effectively immune to everything except light.* It's simply a matter of how the army goes about finding this out and then how they use light as a weapon against her. Lasers, mirrors, take your pick. We're not talking Archimedes and a dozen men with mirrors here, it's now about computer controlled [heliostats](https://en.wikipedia.org/wiki/Heliostat) or lasers perfectly focused on her. Not expensive in military budget terms, easy to design and build, minimal skills required to deploy once the engineers have built it, and, once deployed, largely immune to her powers if properly engineered. If she's sealed her box against chemical and biological weapons then it's effectively a perfectly insulated space. The molecules don't move to radiate or conduct heat, there are no gaps for convection. A perfect oven. **If they know what's going on, she's going to [cook](https://en.wikipedia.org/wiki/Solar_cooker) in her fortress of air.** [Answer] It depends on who's ready for who. Since you specified that both sides are surprised, the super-powered woman would win. Firstly she can surround herself with an unbreakable shield complete with a floor so she doesn't even have to touch the ground. Next, she fills the area around her with tiny 1mm dots at 20cm to 30cm apart from the ground to 2 meters high. The whole area would be locked down and only she has the ability to move. She can now wander the battlefield dispatching everyone and everything. To win the army would need to know what it's up against. If they deployed blinding lasers, the woman couldn't see and therefore couldn't use her powers. Anything short of this they would lose. [Answer] This woman seems anything but [unstoppable](https://worldbuilding.meta.stackexchange.com/questions/4317/what-to-do-about-unstoppable-questions). > > The altered volumes have no visible changes, but only visible light can pass through. > > > **So it's quite easy to kill or injure the woman**, the most expensive part is to understand her true power and provide countermeasures but i don't think that's could be actually economically relevant for a first world militarized nation. Soldiers are not stupid, so starting from a mile apart and knowing that there is a declared enemy some "artillery" (1 mile is not that far) shells will be exploded. If this seems to be a little overkill to terminate a single woman one mile apart lets pretend that some snipers exploded some ammo but the spotters saw something strange and they communicate that somehow she can withstand large caliber bullets. Artillery will start really quickly. Given that she is also ready to fight her best chances are to create a safe-box as big as possible, to keep the maximum available oxigen reserve and to have room to move easily. Artillery shell happen to create a lot of dust and, since her safe-box is impenetrable, every spotter can see that there's something strange that protects the woman because dust clouds are moving as they are confined by a glass structure. Since Kinetic is not working the soldiers will fastly try something chemical, which won't also work untill she will need to "open" her safe-box. Kinetic weapons are kept firing anyhow, the soldiers don't know what they are facing so they won't for sure try to save some shots because apparently ineffective. At least as long as they fire the woman doesn't move a lot. **Now the woman is already in a bad bad spot:** if she keeps the safe-box active she is safe from kinetic and gas, but she has a defined amount of time before she runs out of oxigen. **There's another issue in her safe-box: since "only visible light can pass" she's also deaf respect to the outside!** And this safe-box property should really remain true because otherwise she would have been made deaf (and at least in a confusional state) anyhow because of artillery explosion. If you just add some regular flashbang granades she definitely won't be able to react: * Because of dust/gas/smoke she can't actually see the enemy (which started the fight 1 mile away, but that could have moved relatively far, at a safe distance but in artillery range) and she would move in random direction and moreover the enemy could actually be in every direction. * She can't hear anything from outside the box * She have to maintain the box "on" and sealed because of the poisonus gas * She will eventually run out of oxigen * She would be constantly blinded/confused by a regular stream of flashbangs granade * As soon as someone understand that the visibile light has full effect and the box is sealed the military would use laser to hurt the woman through the barrier: a normal eye could be permanently blinded by an hobbistic laser engraver with just one watt of optical power and that costs less than 20$, an industrialized nation could provide tons of these laser in hours. But in any case i doubt that this will be required. * It could be also possible to try to overheat the woman only by visible light radiation: light is still energy and the barrier won't dissipate any heat and therefore the internal temperature will raise. The only countermeasure for the woman is to let some air escape shrinking the safe box, and then re-seal the box and restore the volume: the gas expansion will low the temperature. The issue is that she's also letting some oxigen escape, reducing her reserve. **TL;DR:** keep an artillery barrage of kinetic, gas and flashbang shells, and she will eventually die. I suggest to use an [AC-130](https://en.wikipedia.org/wiki/Lockheed_AC-130) fleet to do that from the sky without risks for the soldiers. How much would it costs? Several millions of $, lets say less than 50, but this amount won't be anywhere near relevant as military expense for countries like USA, Russia, China, ecc.. See the edited part of the answer: i guess that, at least for the first battle day, the winner would be the one who shot first since she can literally obliterate everything in sight but only as long as the sight is not blocked by gas or dust. --- EDIT: as a sidenote that come to my mind reading other users answers, the women's power is anything but only defensive! If you take 40x40x40m of normal air and compress it to 1x1x1mm (or less, which seems to be feasible given the women's power since there's no minimum limit) you can actually start a nuclear fusion. Therefore she could deliver this well packed energy cube anywhere within her line of sight, and then just release the energy by switching off her air control. I'm not a nuclear engineer but the possibility to deliver thermonuclear millimetrical cubes at wish would be really devastating! 0\_0 The only downside is that for a while (before the compression) she can't control other air to protec herself, but she can decide to compress little less air and keep just enough controlled air to protect herself. [Answer] So here's an option that will allow you to deal with a force of around 5000 combatants that are in the open. This idea *won't* work in a guerrilla combat environment, and forces larger than 5000 will struggle with the volume limits. Also, it only works if your air wrangler can maintain **multiple 'volumes' at once**. Put simply, you can suffocate your enemy force. The average human head is around 1500 cm3 in size (perhaps a little smaller) which means that if you allow for around 2000 cm3 per soldier, you can create a 'helmet' of a solid force around each of their heads. This helmet barrier seals around the neck, and because it's solid, your soldier will suffocate as they can no longer breathe the air as it's acting as a solid. Also, it will hold them *exactly* in place because the barriers are stable relative to the earth. Every barrier is also a glove-like fit for the head it surrounds, so it's impossible for the soldier to get out of it. Give it 20 mins to be sure, then you release and you're done. Ideally, your air wrangler should be up on a peak, able to look over the entire approaching army at once. Further, you don't want them in APCs or other mechanised weapon platforms like tanks because of the line of sight restriction. This solution fails quickly when dealing with an armour division, although putting an air barrier 'plug' into the barrels of all the tank guns so that the shells blow up inside them seems to be a logical solution to that as well. Ultimately, this can be used as a *very* offensive weapon, but it involves the use of many small volumes in order to achieve it. Whether or not you're encasing 100 tanks in a thin shell, plugging 10k gun barrels, or suffocating 5k soldiers, you need to do it all simultaneously. That could be a lot of focus that needs to be maintained but it's doable with the rules you've set out. How to defeat her? Well, it's the ant approach; superior numbers. If you have a force of soldiers larger than (say) 15k, you might not have enough volume capacity to (say) plug every gun barrel, and you will only be able to suffocate them in stages. A large number of tanks may not be able to shoot because of the plugged barrels, but they can still crush your single combatant by running her over (**edit**: This is of course assuming that the 'static' nature of the air barrier doesn't actually leave the tank immobile because the plug is stopping the entire tank from moving). Ultimately to defeat her, you have to overwhelm her capabilities and the 'cheapest' solution to do that would be a very large number of human soldiers if using conventional tactics. Even cheaper *might* be a small number of special forces soldiers trained in guerrilla tactics to sneak up on her if you have that option. All up, your air wrangler is a very dangerous individual and if she attacks the weak points of soldiers and equipment and has a good vantage point, she's going to be able to outlast quite a considerable force. [Answer] **Deception and Misdirection** The military show of force keeps her attention. They don't move forward to provoke her action, but spend the day noisily arriving, battalion after battalion, moving into initial positions that she can clearly see. Then noisily shifting position as the next unit arrives. It looks like they are trying to impress her with sheer numbers and kit... ...but they are not. A small group of snipers arrived before the first main body (preferably long before dawn), circle around and approach from behind. Avoiding her field of view might take them most of the day, but even "open, grassy plains" has dead space to sneak through. A second group of snipers conceals in dead space in front of her, so if she walks forward she will enter their kill zones. They are the backup plan. One clear shot during the afternoon. Battle over. Force Estimate: 3 Armor battalions, 3 Mech Infantry battalions, 3 Light Infantry Battalions Single-use Cost Estimate: About \$900 million in Tanks, \$225 million in Bradleys, \$30 million in personal kit (including personal weapons), and about \$500 million in the training and preparation (some of which takes *years*). Plus fuel and ammunition and other basic sustainment for the mission, plus housing, food, medical, parts and maintenance, etc. Note that the more accurate mission cost is designed to be very low - if the mission succeeds, not a single tank will be damaged, not a soldier lost, and barely any ammunition expended. Only a hard day's worth of burned fuel. However, this plan rejects the premise that the army doesn't know they are fighting a single super-powered person, who has the element of surprise on her side. This is how surprise works the other way. [Answer] **Siege** This woman has only defenses. Solid air of the volumes described is not much of an offensive weapon. You can easily lay siege to her improvised defenses. You can defeat this woman with a ring of snipers or a few pieces of artillery. Roman technology will do. She must maintain her impenetrable barrier circumferentially around herself to protect from shrapnel or bullets. She can flash her barriers on and off to get fresh air but eventually she will get thirsty. The soldiers laying siege take shifts. If the soldiers laying siege tire of this they can drop / throw incendiary bombs. Impenetrable air probably still conducts heat. If she decides to advance until she sees an opponent or finds some water, she will encounter land mines / pitfalls. [Answer] This question is rather odd... because as defensive as the woman is against physical attacks, her barriers are not shielding her against light. And Light - or rather EM-radiation - is what will make the military win as soon as they can field the right weapons. ## Breaking the ability to fight ### Deep Red Yep, Microwaves are nothing more than light in the deep red sector as all light is basically EM Radiation and thus can interact with matter via Photoeffect. Even the visible Red Light bordering the IR is quite good at heating up matter. Microwaves, which are not too far away from red light have been tested for riot control means in the past. Give the woman a nasty sunburn with a very large spotlight till she surrenders or cook the woman within her protective shell of hardened air till she is dead. Just a couple of these Hollywood Spotlights should suffice. Win Miitary by breaking the opponent. ### Laser She needs to see, right? crack out a high powered laser, then aim for the eyes and blind her. No sight, no new barriers. Which means she either opens herself to other attacks like gas, surrenders or suffocates. Win Military by shattering the ability to fight. But we can do better: # Supreme Excellence approach > > To fight and conquer in all our battles is not supreme excellence; supreme excellence consists in breaking the enemy's resistance without fighting. > > > ### Psychowar She can see if there is light. But light can be very disorienting: place strobelights all around and bombard her with a nonstop flashstorm until she screams in agony or suffers a stroke. Win Military by breaking the will to fight. ### Denial As long as the military can stop the woman from fleeing, she has to stay. As she stays, she has to support herself. And a military of just a couple hundred men can deny access to resources to her. Win Military by atrition. ### Trickery Or... they deliberately don't deny access at some points. Not because they are mercyful, but becuase the food is laced with plagues or drugs to take her out. Win military by surpreme excellence. ]