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I know this question is asked a lot in other subreddits, but I want to hear it from here: what's the most interesting, thought provoking fact you know? | The Romans had tacky shot glasses shaped like gladiator helmets. | [
"Once, for example, he strode into our seminar room apparently deep in thought, then turned around and walked back out. We could hear him pacing up and down the hallway. Finally, he returned and apologized. \"I've been struggling to solve a puzzle\", he explained. \"I know it's not our topic for today, but I hope y... |
why does a dishwasher seem to slowly loose the ability to clean over a few years, but a washing machine works the about the same until it breaks? | You’re more likely to have food particles left on plates than you are to have dirt and debris on clothes. The food particles and other stuff likely caused a clogged filter. Your washing machine also has a filter FYI | [
"Washing machines perform several rinses after the main wash to remove most of the detergent. Modern washing machines use less water due to environmental concerns; however, this has led to the problem of poor rinsing on many washing machines on the market, which can be a problem to people who are sensitive to deter... |
How are quantum computers actually implemented? | In superconducting quantum computing one typically uses Josephson junctions (superconducting tunnel junctions) to make anharmonic resonators that act as qubits. Junctions are made by litography like classical CPUs. Such qubits are prepared by microwave pulses that correspond to rotations on the Bloch sphere. Entanglement between qubits is generated by variable coupling (in the simplest case adjusting current through a Josephson junction changes its inductance and thus coupling). The Junctions are almost purely reactive so no loss is associated with them. Readout is usually done by reflecting a microwave pulse from a coupled microwave resonator and then determining the phase of the reflected pulse (which depends on the state of the qubit). Losses etc. limit the coherence time within which one has to do all the operations. The actual arrangements tend to be a bit more complicated, but that's the general idea. One gets pretty far with the experimental side of things by just doing classical circuit simulation. Understanding the many particle behavior between readouts maybe no so much. | [
"A quantum computer is a computation system that makes direct use of quantum-mechanical phenomena, such as superposition and entanglement, to perform operations on data. Quantum computers are different from digital computers based on transistors. Whereas digital computers require data to be encoded into binary digi... |
how does sentience arise during gestation? | The fertilized egg has different genetic material than either parent, so at that point it would be considered a different living creature.
Your other questions are more social questions, insofar as the rights of the unborn are concerned, which don't have any objective answer. | [
"Electrical brain activity is first detected between the fifth and sixth week of gestation. It is considered primitive neural activity rather than the beginning of conscious thought. Synapses begin forming at 17 weeks, and begin to multiply quickly at week 28 until 3 to 4 months after birth.\n",
"Fertilization ma... |
why do 3d movies hurt my eyes? why do i have issues when others don't? what's going on with my vision? | I have a similar issue. I asked my eye doctor and was told that the astigmatism is what causes the headaches and such. Something to do with how the eyes shift to focus. I can't go to 3D movies because I get wicked headaches. | [
"There are two primary effects of 3D film that are unnatural for human vision: crosstalk between the eyes, caused by imperfect image separation, and the mismatch between convergence and accommodation, caused by the difference between an object's perceived position in front of or behind the screen and the real origi... |
Is it likely that our current model of fundamental particles is unadvanced? | It will grow; that's a near certainty. Pretty much any extension to the Standard Model includes new particles, and we know that the Standard Model has to be extended.
For one thing, it doesn't include gravity. This isn't a big deal in everyday life, but when energies get high enough - like they were right after the Big Bang, or near the center of a black hole - the issue gets forced, and our present theories of physics don't give sensible answers. So there *must* be something new appearing by the time you reach those absurdly high energies, and these almost always bring along new particles.
There are also reasons to expect new physics "on the way," in order to answer other theoretical issues. Take, for example, the [strong CP problem](_URL_0_). Our theory of quarks, quantum chromodynamics, has a free parameter which experiments suggest is very small or zero. But this is unnatural - quantum effects should generically make this parameter larger than that. One popular solution is the Peccei-Quinn theory, which predicts new particles called [axions](_URL_2_).
Another thing that should happen at higher energies is that two of the fundamental forces - the electroweak force and the strong force - should unify into one, and that would also require new physics with new particles. [Supersymmetry](_URL_3_) is one popular candidate for this, and that would at least double the "periodic table of particles," because it postulates that all particle species come in pairs, and so far we've only ever observed one half of each pair.
Neutrinos were predicted in the Standard Model to be massless, but experiments show at least some of them do have a very small mass. This might be a sign of new physics, with new particles.
There is a huge amount of very strong experimental evidence that the majority of the matter in the Universe is [dark matter](_URL_1_) which is not described by any of the particle species in the usual Standard Model. This new matter is heavy and abundant, but doesn't interact via the electromagnetic force so it doesn't emit light. Since we observe the Universe using light, this makes it very hard to spot - so far we've only noticed it through its gravitational effects. This new dark matter particle (or particles) may be something I've already mentioned, like an axion or a supersymmetric particle, or it might be something else entirely.
Along the same lines, the accelerating expansion of the Universe could be a sign that the Universe is filled with an exotic new [dark energy](_URL_5_), or that gravity is described by a theory besides Einstein's (which is the present gold standard). The simplest explanation - called a cosmological constant - doesn't introduce any new particles, but pretty much every other solution (both dark energy and modified gravity) does.
Finally, there's a lot of evidence suggesting that the Universe, very shortly after the Big Bang, went through a period of hugely accelerated expansion called [inflation](_URL_4_), driven by some new exotic energy which would also have at least one corresponding new particle, called the inflaton.
---
**tl;dr** Almost certainly. We know our current theories are incomplete in one regard (because gravity doesn't fit in with the rest of physics), and there is reason to believe in a few other possible extensions at lower energies. All of this new physics should bring in new particles. | [
"The currently accepted theory describing elementary particles and their interactions is known as the standard model of particle physics. This theory provides a unified description of three of the fundamental forces of nature: electromagnetism and the strong and weak nuclear forces. Despite its remarkable success i... |
How did the astronauts that have landed on the moon manage the descent to and especially ascent from the surface? | The [command service module](_URL_3_) was inserted into orbit about the Moon, it didn't stay in one place.
The [lunar lander](_URL_1_) was equipped with at least one rocket propulsion system to slow the descent, and more engines were used to produce the thrust necessary to re-enter lunar orbit to rendezvous with the CSM.
The ascent had to be timed to be close enough that final adjustment before docking with the CSM could be handled by small thrusters (named reaction control thrusters I believe) that could provide fine control over the craft's orientation and speed.
The rockets used to lift the ascent portion of the lander from the Moon shouldn't have had much of an effect on anything except directly below the craft since there is no atmosphere to carry shockwaves or blow wind. You'd see some small effect where the reaction mass actually impacted the surface but much of it would scatter off so quickly as to have no discernible effect on larger objects as the lander gets further and further away. You can see in [this video](_URL_0_) that quite a bit of lunar regolith is being displaced by the descent stage as the engines are being fired quite close to the surface for a long period of time, contrasted with when the craft lifts off the thrust doesn't appear the kick up nearly as much.
There were multiple different types of fuel on the lander but the bulk was stored near the bottom-half as [this image](_URL_2_) depicts. | [
"At 64 hours into the flight, the crew began to prepare for Lunar Orbit Insertion 1 (LOI-1). This maneuver had to be performed perfectly, and due to orbital mechanics had to be on the far side of the Moon, out of contact with the Earth. After Mission Control was polled for a \"go/no go\" decision, the crew was told... |
what is a luxury tax as it refers to sports teams? how does signing potential free agents possibly impose the tax on a team? | It is a sort of soft cap. A hard cap like football is you can’t spend more than x amount of money on player salary . A luxury tax is a soft because you can spend more than the cap but at a penalty. If you spend more than x amount of money you will have to pay a penalty of a certain percentage for every dollar you go over the amount ultimately making signing players over the cap even more expensive. This money in some sports is given to teams with lower payroll. It is meant to make up for some teams being in smaller markets. | [
"A luxury tax in professional sports is a surcharge put on the aggregate payroll of a team to the extent to which it exceeds a predetermined guideline level set by the league. The ostensible purpose of this \"tax\" is to prevent teams in major markets with high incomes from signing almost all of the more talented p... |
What would it be like to be on a planet in a Quasar galaxy. | I am in a group that studies quasar host galaxies. That is galaxies with a quasar in them. This is an active field so things are always changing but this answer will be my best guess considering current research.
Lets only consider disk galaxies. In that case most of the emission from the quasar will not get into the disk. The high energy radiation will be mostly blocked by a region of thick molecular clouds around the quasar. At the distance of Earth it would probably look impressive in the night sky. But probably have no greater significance for life. | [
"BULLET::::- 1991: The novel \"The Singers of Time\" by Frederik Pohl and Jack Williamson visits a parallel universe totally covered in Dyson Shells, where only the farthest quasars are visible (already covered, but the light from them is still traveling). They were constructed by a formerly biological race that sl... |
why do some martial artists yell in movies and at demonstrations? | There are many reasons. Exhaling tightens the diaphragm and tenses the body, making strikes more powerful and protects the body from counterstrikes. This is why UFC fighters always make that "tsss" sound whenever they throw a strike.
I am also fairly sure that yelling has to do with rituals used by martial artists to "summon chi" to certain areas of their body. It gets adrenaline pumping and (arguably) enhances performance. | [
"Martial arts films contain many characters who are martial artists and these roles are often played by actors who are real martial artists. If not, actors frequently train in preparation for their roles or the action director may rely more on stylized action or film making tricks like camera angles, editing, doubl... |
what do people mean when they blame the "older generation" for ruining housing and the economy? | In general, the baby boomer generation went to college, got married, bought houses and retired from companies they had worked for for many years. Millennials, on the other hand, generally haven't got the earning power to do that. They often graduate college in debt or skip college entirely, generally don't have long-term relationships or have several non-traditional relationships, can't afford to buy houses and change jobs when opportunity arises or circumstance dictates. This is because the cost of college has skyrocketed, the cost of housing has skyrocketed, no one can afford to tie themselves financially to another person because divorce is expensive, and companies no longer provide the cradle-to-grave benefits that they once did since it makes more financial sense to offshore production to somewhere where companies don't have to pay for pensions, safe working environments or living wages in America. Since boomers are generally making the decisions at large corporations, speculating in the housing market, lobbying for insurance companies and by and large were in charge during the time millennials came of age, many millennials blame them for screwing over their generation. Boomers usually respond with "work harder, like we had to do" and ignore the fact that prices and values for *everything* were much, much lower when they were the age of the millennials. | [
"The coming of age of this generation coincide with the economic downturn starting with the collapse of the stock market bubble in 2000. This led to rising unemployment until 2004, the same time this generation was entering the workforce after high school or college graduation. Additionally, in the new economy, whe... |
How does the Foucault Pendulum work if it is within Earth's atmosphere that is rotating along with Earth? | The Foucault pendulum has nothing to do with the atmosphere. The relevant forces are gravity, tension, and the **Coriolis force**.
The Coriolis force is simply due to the fact that the Earth is rotating, so a reference frame fixed with respect to a point on the surface of the Earth is non-inertial.
> then I should be able to hover above Earth in a helicopter and let the Earth's rotation do my traveling for me.
Well the Coriolis force is zero if the helicopter is hovering in place. | [
"When a Foucault pendulum is suspended at the equator, the plane of oscillation remains fixed relative to Earth. At other latitudes, the plane of oscillation precesses relative to Earth, but more slowly than at the pole; the angular speed, \"ω\" (measured in clockwise degrees per sidereal day), is proportional to t... |
why do stripes look wonky on videos? | In real life, spots on a line can be anywhere they want.
In videos (assuming vertical lines on a 1080p video) each spot has only 1080 places it can possibly be. If the line is perfectly straight, they will line up nicely like that, but if not, the recording device will have to choose a spot to put each part of that line, when really it should be between the two points.
for example: If you drew a staircase, and then connected a line to all the stairs, you would get a nice straight line. But if you could only connect every stairs, and had to put the other stairs in one or the other pile, it would look very uneven and weird.
also a bunch of technical stuff with cameras and pixels, but this is the basics.
| [
"Zebra patterning (or zebra stripes) is a feature found on some prosumer and most professional video cameras to aid in correct exposure. When enabled, areas of the image over a certain threshold are filled with a striped or cross-hatch pattern to dramatically highlight areas where too much light is falling on the i... |
in videogames, why is the animation of simple things so damn difficult( kissing, drinking water, playing an instrument, etc? | One of the difficulties with some of those things is that human bodies are soft and squishy.
Models in games are made up of lots of triangles. To make part of the model deform means moving and stretching those triangles. You need a lot of triangles to make it look convincing.
This is why there tends to be a lot more triangles in a character's face than the rest of their body. Faces deform in lots of complicated ways when someone is speaking, so you need a lot of detail to recreate that.
In real life when someone presses something against a part of their body, such as another persons lips, it squishes a bit. Recreating those "squishes" means you need even more triangles. And more triangles means more processing power is needed.
Also you'd probably need some kind of soft body physics simulation to work out exactly how those triangles need to move when something presses on them. However that doesn't necessarily need to be done by the game itself for things like cutscenes.
This is far too expensive for most games, both in terms of processing power and amount of work/money needed to do it. So most games don't, and just settle for an awkward "wooden" look when characters interact with things. | [
"The player animations were created using a new animation process called Real Motion Control, which involved motion capture. Game designer Sam Player explained the concept behind this process: \"The reason everything always ends up looking choppy in [most motion capture] games is that the machines can't store all t... |
why don't we have jungle bears with green fur? | Mammals only have 2 types of pigment in fur/hair: eumelanin (black/brown) and pheomelanin (red/orange). Combinations of these pigments give a wide range of colors, from black to light brown to auburn to orange to yellow blonde. Absence of these pigments results in white, and in icy habitats, bears with little or no pigment are more likely to survive long enough to mate. No combination of these 2 pigments can create green (or blue or purple), which is why no mammals have green fur. | [
"The black bear is much smaller than the brown bear. They are found in larger numbers on the mainland of Alaska, but are not found on the islands off of the Gulf of Alaska and the Seward Peninsula. Black bears have been seen in Alaska in a few different shades of colors such as black, brown, cinnamon, and even a ra... |
what does your computer do when it "shuts down"? | Software can often store information in temporary places. When you go through a shutdown/quit/exit process, it's not just stopping that program, it should also be reverting any of those file/directory locks and bringing the 'temporary' information back to a 'permanent' state.
When you just pull the cord out of the back of your computer, these programs don't get a chance to do that properly. However, computers do crash so developers have learned to store some of temp info in a permanent location just in case. For example, if you have a Microsoft Word document open and you pull the power cord out, the next time you start Word it will say something like, "Microsoft Word didn't shut down correctly. Would you like to continue working on any of [these] recently opened documents?" | [
"Normally, when the computer is shutting down, every mounted storage will undergo an unmounting process to ensure that all queued data got written, and to preserve integrity of file system structure on the media.\n",
"In Microsoft Windows and ReactOS, a PC or server is shut down by selecting the Shutdown item fro... |
How'd the Dutch rise, colonize, and build one of the biggest navies in the world while they were constantly fighting the Spanish? | And where did most of the wood come from to build their ships? | [
"In the Dutch Golden Age, spanning much of the 17th century, the Dutch Empire grew to become one of the major seafaring and economic powers, alongside Portugal, Spain, France and England. Science, military, and art (especially painting) were among the most acclaimed in the world. By 1650, the Dutch owned 16,000 mer... |
what is newton's concept of absolute space? | You may be having this problem understanding it because you've grown up in a world that has known Newton was totally wrong about this for several generations now. Relativity and quantum mechanics are familiar to you, and the complexities that come with them.
Throw out this complexities and think of the universe like a five year old. The entire universe, for Newton, was literally how a five year old sees their house. It is stable, unchanging, objective, and knowable. A clockwork universe. If you know the gears, you know where everything is going. It was a primitive view of how things worked.
Think like a man who had nothing but math to figure EVERYTHING out on his own. He got some things wrong. How he got them wrong was how a math genius would get it wrong: he thought everything was set.
Now we know everything is relative and nothing is clockwork. It's all quantum probability. | [
"Later scientists pointed out (as did Newton) that the laws of mechanics were the same for all observers that differed only by uniform translation; that is, all observers that differed in motion only by a constant velocity. Hence, \"absolute space\" was not preferred, but only one of a set of frames related by Gali... |
If gravitational waves propagate not instantaneously, but instead at the speed of light, does that mean gravity waves can interact with and influence other gravity waves? | Yeah, sort of. You can get [interference](_URL_1_) of lots of gravitational waves. You won't really get a refraction, explained well in [this post](_URL_0_).
Pulsar timing experiments, among others, are looking to detect, among other things, a stochastic background of gravitational waves, which comes from a superposition of waves coming from lots of supermassive black hole binaries in merging galaxies. | [
"In general relativity, a gravitational wave is a space-time perturbation which propagates at the speed of light. It then curves slightly the space-time, which changes locally the light path. Mathematically speaking, if formula_1 is the amplitude (assumed to be small) of the incoming gravitational wave and formula_... |
In ancient Rome what was the difference between a freedman and a citizen? | Many scholars argue that part of what made Rome great was its relatively lenient policies regarding manumission, that is, going from slave to freedman (whose children would then be full citizens) was a great motivator for slaves to be quiet, content, and productive. R.H. Barrow in his work, Slavery in the Roman Empire, went as far as to say: “The full opportunities for civilized life could only be fully used in freedom, no doubt, but slavery was an apprenticeship.”
Now as you can imagine, depending on the type of slave, his odds differed greatly depending on location, job, master's favor, etc. A slave in the tin mines in Britannia was likely doomed to an early grave whereas a slave who managed his Master's shop had much better odds.
But on to the details. What made manumission so attractive was freedman were given rights and privileges (legitimate children, transfers of property, marriage, wills, etc.), but along with these rights came responsibilies (obsequium - a freedman's obligations to preform operae [obligated services and inheritance rights] and maintain relations with his former master, the relationship was not unlike the well-established Roman patron-client system). These *operae* could take many different forms, perhaps, if his master fell on hard times, his former slave would be required to put him up. Generally, the conditions of the *operae* would "negotiated" during the manumission process. Although, you can imagine the slave had little leverage in the matter. Former slaves could not be charged in money by their former master, only services, however, if the freedman preferred to give cash he could. It is also important to note that slaves who had squirreled away enough cash to buy their freedom did not have these obligations.
Freedmen, of course, had some restrictions, most notably not being able to run for public office or access to the prestigious priesthoods. Military service was generally a no-go whether it be in the legions or urban cohorts (A general rule, I am sure the Romans broke it if they were desperate enough). Also, punishments in law were more severe for ex-slaves. Their was also a social stigma attached to a freed slave. He was likely a foreign prisoner of war, separated from country, tradition, his family, and even his given name and birthday. Freedmen were endless ridiculed and mocked for these things by the natural born Roman citizens (often jealous of the ex-slaves connections, wealth, or new found position).
However, many ex-slaves also had a host of factors in their favor. Trade and manufacturing were mostly run by slaves or former slaves (tradition forbade good, moral Romans of the senatorial class from taking part, so they sent their slaves to conduct business). Their talents and skills for fabricating goods, importing and exporting, and conducting business served many slaves well in their freedom. The Imperial administration and bureaucracy was, in large part, run by slaves and freedmen. As you can imagine, with these conditions present, some former slaves rose to immense prominence whether by administrative or financial means. Just so some basic searches on Claudius' cavalcade of freedman (Pallas, Callistus, and Narcissus come to mind although I'm sure there are more for other emperors) and their various schemes for power. However, it is important to remember that many of the accounts of these men are horribly biased and are from men of elite families like Tacitus. These social elites, who had so recently lost a tremendous amount of influence in the collapse of the Republic, were wildly jealous of these former slaves and their meteoric rise to power.
That went on a lot longer than I intended, but I hope it was helpful. I, unfortunately, can't really tie it to more modern times, but hopefully someone else comes along and can add to this.
Some recommended reading if you have further interest (my post is heavily based off these readings):
Slavery in the Roman World - Sandra Joshel
Slavery in the Roman Empire - RH Barrow (a bit antiquated, but a good read nontheless)
Greek and Roman Slavery - Thomas Wiedemann (fantastic collection of primary sources) | [
"In ancient Rome they were called , a freedman (feminine: \"liberta\") or an emancipated person who acts for and on behalf of its former master, who became his patron (). During the Empire period and after the judgment of a magistrate they were freed from a . Despite being freed by manumission and acquiring the Rom... |
Have people always thought nature is beautiful? | This is going to answer only a small portion of your question, but I can tell you that literary scholars view the Romantic Movement as making definite contributions to Modern European/American understandings of nature as beautiful. Romanticism rose to its peak alongside the industrial revolution and acted as a sort of artistic backlash to a cultural emphasis on capitalism and urbanization. It frequently invoked nostalgic images of agricultural lifestyle (called pastorals) and emphasized the beauty and power of nature over manmade artifice. It also gave us the idea of the sublime, a sense of terror or wonder inspired by a realization of how small you are in light of nature’s majesty.
While romanticism developed in England as an offshoot of sentimentalism, with the classic examples of romantic works being very English-centric, the movement resonated with, and was appropriated by, pretty much every North American and European culture. There’s a huge amount of romantic literature, art, and music from all over the world during the late 18th and early 19th century. I don’t think there’s any question that romanticism is at least partially responsible for giving us a general cultural understanding of nature as containing a lot of beauty, and I also think that this understanding is a direct consequence of the modernizing process.
To put it in more clear terms, **while people almost certainly saw nature as beautiful before romanticism/modernity, I don’t think they thought of it in the same was as we do now.** The industrial revolution started a long process that gradually removed the influence of nature from people’s day–to-day lives and consequently it became ripe for artistic pastiche and nostalgia. It’s easy to fantasize about living in a log cabin in the woods when you’re commuting to work in a traffic jam every day, and that distinctly modern circumstance gives such fantasies a power that simply wasn’t present for a lot of pre-19th century people who were stastically more likely to perform agricultural labour and live outside of cities. That’s my personal understanding as a scholar of late 18th century literature anyways.
However, romanticism is a little bit outside my field so for better information I recommend [this text](_URL_1_) by Michael Ferber, which comes from the excellent “short introduction” series.
It also has a surprisingly comprehensive and well cited [Wikipedia page](_URL_0_).
Also, I can’t emphasize enough that Romanticism is a highly Euro-centric explanation for why we consider nature beautiful. For example, the 17th century Japanese poetry of Matsuo Basho demonstrates an incredibly powerful belief in the beauty of the natural world almost 200 years before romanticism (or Japan's own process of Modernization) came to be. I assume that every culture has its own unique relationship to artistic depictions of nature and I'm sure you could find many examples that have “always” found it beautiful. | [
"Beauty in nature has historically been a prevalent theme in art and books, filling large sections of libraries and bookstores. That nature has been depicted and celebrated by so much art, photography, poetry, and other literature shows the strength with which many people associate nature and beauty. Reasons why th... |
tabletop rpgs... | I'm sure everyone's heard of Roleplaying in some form or another. It may be more familiar to you based on my guess of your occupation. Tabletop RPGs are just an extension of that.
Tabletop RPGs are just your regular Roleplaying ("acting as someone else") with some board-game mechanics added in for fun and to serve as a mechanic to make things flow better.
Let's use an example: I'm playing a tabletop RPG with my friends. One person is running the game (kind of like a referee). He tells us what's happening. He tells us "Okay, a monster has popped out in front of you and he looks angry." The choice is then up to us what to do. I might say "I'll try to charm him with my good looks" To find out if that works or not, I'll probably roll a dice. If I roll well enough, it will work, and the Referee will tell us how well it worked, and how the monster reacts. The Ref might have already figured this all out ahead of time, or maybe he's making it up as he goes. When things get more in depth, you have a "character" that you're playing and sometimes that character has certain attributes (he's strong, or fast, or knows magic) that are represented by scores, and the scores are used to help in the dice rolls. Typically as you keep playing, you keep the same character and that character gets rewards (new equipment to help him, becomes more powerful, learns more things). Winning or losing all depends on the referee, and the game is about enjoying the adventure you're acting out together.
Essentially, you are taking play acting (improvisational) and combining it with board games (dice rolls tell you how well you progress) and rewards for continued play/success. The great thing is just about everything is controlled and determined by the referee, so you can keep it within the boundaries you need to.
You can make games on your own, but it can be daunting. There are plenty you can buy too. Perhaps go into your local gaming store and ask for a very beginners/kid-friendly rpg. You might even ask at the local store if you can watch some people play a game or two, and I know the company that makes Dungeons & Dragons encourages retailers to run game events once a week to help people connect and play together. (Though D & D might be a bit advanced for beginners) For more advice on getting yourself comfortable with running a game for others, check out information on "How to be a DM" or "How to be a Gamemaster".
For further reference, here's some advanced players playing Dungeons & Dragons: [Penny Arcade plays D & D](_URL_0_) | [
"Tabletop and \"pen-and-paper\" (PnP) RPGs are conducted through discussion in a small social gathering. The GM describes the game world and its inhabitants. The other players describe the intended actions of their characters, and the GM describes the outcomes. Some outcomes are determined by the game system, and s... |
when jumpstarting a car, why is it important to always start with the positive gauge (red) ? | Sometimes, when you make the last connection, a spark jumps from the cable to what ever you're about to clip it to. If you start with the red cable, then the last connection will be made to an unpainted metal part of the car. That way, if a spark occurs, it hits the metal part of the car, rather than the battery, which reduces the chance of igniting hydrogen gas coming from the battery. | [
"The player's car will jump through the air between sections of each race track, during which stunts can be performed. Stunts are an integral part of the game, as much as racing against the clock. As a car jumps between sections of track, the player can make the car spin around any axis: barrel rolls, end-over-end,... |
How much weight can the human foot support? | I know nothing about biology, but as an interesting lower bound, the heaviest [deadlift](_URL_0_) on record is 1180 lb. Adding the weight of the weightlifter (reported to be 275lb) shows that a (extremely strong) human can hold at least 1455lb on two feet, or 727.5lb per foot. I highly doubt that anyone could walk holding that weight, though! | [
"The human foot is a strong and complex mechanical structure containing 26 bones, 33 joints (20 of which are actively articulated), and more than a hundred muscles, tendons, and ligaments. The joints of the foot are the ankle and subtalar joint and the interphalangeal articulations of the foot. An anthropometric st... |
In movies, oftentimes a command given to archers is “fire!” I saw somewhere that the command wasn’t actually the word “fire”. What would someone say in order to command an group of archers to shoot arrows at a target? | To get the simple things out of the way first, “fire” is generally not considered the proper term for shooting a non-gunpowder weapon. Early gunpowder weapons were triggered by applying a fire source, often a slow-burning wick, into the gunpowder via a hole in the side of the weapon. In the earliest examples this was done manually, but from the invention of the match-lock this was done via a trigger. This literal application of fire to shoot the weapon is generally accepted as being the reason why we use “fire” to mean “shoot”. Since bows, crossbows, slings etc. don’t use fire as an ignition system, it’s generally held to be inappropriate to use the term. I’m of half a mind that the colloquial use of “fire” has sufficiently diverged from its origin that I don’t mind when people do, but some people are sticklers for such things. I don’t find the use of the term “fire” in medieval-esque films to be any more jarring than the use of any English term developed post-1400. For example, I don’t find it weirder than the use of the term “crusade” in Kingdom of Heaven, even though nobody during the Third Crusade would have used that term. That said, I’m also not here to degrade anyone for nit-picking things in movies, I’m hardly without sin so I’m not about to throw some stones.
For much of this answer I’m going to be focusing on longbow tactics used by the English during the 14th and 15th centuries. This is mostly due to that being a high point in both the use of massed archery and in sources talking about archery and archers. Archery was a staple of warfare for the entirety of the Middle Ages, and there were huge differences in its role in different periods and regions.
As to what would have been said instead, the answer is kind of impossible for a couple of reasons. The most basic reason is that we don’t have a lot of really detailed accounts of medieval battles and tactics, at least not to the degree of detail that would include the instructions individual commanders gave soldiers under their command. When we have detailed accounts of a battle they nearly always come from chronicles, which are not an inaccurate source but are also inevitably a somewhat romantic view of the events (degree of romanticism does vary substantially). Some of these accounts were written by eyewitness, Jean le Bel’s account of Crecy (1346) is perhaps the most famous, but many were not and in both cases the accounts were often written down years after the fact. This means that while the general strokes of these accounts are usually pretty accurate, we should be a little wary of placing too much faith in the finer details of things like who said what and when. On the occasions when we do get a fairly immediate account from someone with a good reason to be informed of the events, they often look like this:
> Because we well know that you willingly will hear good tidings of our Lord the King and of his affairs in Scotland, we give you to understand that on the Monday next before the Feast of Saint James (July 25th), there came tidings unto the Lord the King where he was staying, six leagues beyond Edeneburg, that the Scots were approaching directly towards him. As soon as he had heard this, he moved with his host towards the parts where the Scots were; and on the morrow the King arrived in good time, and found his enemies prepared to give battle. And so they engaged, and, by the grace of God, his enemies were soon discomfited, and fled: but nevertheless, there were slain of the enemy in the day’s fight 200 men-at-arms, and 20,000 of their foot-soldiers; wherefore we do hope that affairs yonder will go well from henceforth, by the aid of our Lord.
That’s a [letter from the Bishop of Litchfield and Coventry on the event of Edward I’s victory at Falkirk in 1298.]( _URL_0_) It’s not exactly brimming with detail. Official, or semi-official, dispatches in the wake of major battles usually look like this. A quick description of the events in broad strokes, and usually a off the cuff figure for how many enemy dead. Sometimes you’ll get a bit more tactical detail, but I wouldn’t hold my breath for it.
When we can glean more detail on the nitty gritty details of medieval warfare, such as when we’re using chronicle sources, the picture they paint is very different from what you see in most movies. A lot of films show medieval warfare as much closer to early modern or modern conflicts. You can see this in the idea of a designated archer commander ordering his troops when to fire, sort of like how we imagine the tactics of volley firing in modern black powder warfare (how accurate that image is for that time I’ll leave to someone else). There are inevitably numerous differences between each individual medieval battle, so generalisations are going to be a little problematic, but by and large medieval warfare seems to have been structured around a much higher level of preparation, and an inevitable loss of control during the actual engagement. There isn’t a total loss of control, we know from the Battle of Hastings for example that commanders were able to rally fleeing troops and execute complex cavalry movements in the heat of battle, but by and large medieval commanders didn’t seem to expect that their plans would survive contact with the enemy.
In this situation, then, much of the available evidence suggests that commanders could control when their archers started shooting their bows but exerting strict discipline onto their rate of fire does not seem to have been a priority. Whether this is a failure of discipline really depends on what you think the purpose of massed archery was. If archers were intended to release killing blows on their opponents, then arguably a more concentrated and controlled system of shooting was better. If instead you agree with Kelly DeVries assessment of the longbow, that it was a tactical tool designed to demoralize and control enemy tactics, then laying down a sustained rain of arrows was the goal, and something akin to volley fire wouldn’t even have been the desired outcome.
As a case study, let’s consider an account of the Battle of Agincourt (1415) by Enguerrand de Monstrelet. Enguerrand was a French chronicler who wrote a continuation of Froissart’s *Chronicles*, arguably the most influential account of the first half of the Hundred Years War, to cover the period 1400-1444. Enguerrand wasn’t present at Agincourt, he was only about 15 when it happened, but his account is one of the most often cited and while he’s not without his flaws he’s an overall pretty good source. This excerpt begins with Thomas Erpingham, a knight in the service of Henry V who is generally credited with having command of the archers at Agincourt, ordering the attack.
> Sir Thomas, in the name of the king, exhorted them all most earnestly to defend their lives, and thus saying he rode along their ranks attended by two persons. When all was done to his satisfaction, he flung into the air a truncheon which he held in his hand, crying out, “Nestrocque!” and then dismounted, as the King and the others had done. When the English saw sir Thomas throw up his truncheon, they set up a loud shout, to the very great astonishment of the French. The English seeing the enemy not inclined to advance, marched toward them in handsome array, and with repeated huzzas, occasionally stopping to recover their breath. The archers, who were hidden in tile field, reechoed these shouts, at the same time discharging their bows, while the English army kept advancing upon the French.
> Their archers, amounting to at least thirteen thousand, let off a shower of arrows with all their might, and as high as possible, so as not to lose their effect: they were, for the most part, without any armour, and in jackets, with their hose loose, and hatchets or swords hanging to their girdles; some indeed were barefooted and without hats.
“Nestrocque!” roughly translates as “Now Strike!”, but there is some room for interpretation. I’ll leave aside debates about exact meaning, and whether or not this phrase was actually used or if it’s an invention of Enguerrand, and focus on the broad point. The archers are given an order to attack, but not detailed instructions on how fast to shoot or targets. We have a few other relevant excerpts from the battle, you can read a full account [here]( _URL_1_), including one ordering the English advance:
> The English loudly sounded their trumpets as they approached, and the French stooped to prevent the arrows hitting them on the visors of their helmets; thus the distance was now but small between the two armies, although the French had retired some paces.
And one where the archers discard their bows and join the melee:
> The English took instant advantage of the disorder in the van division, and, throwing down their bows, fought lustily with swords, hatchets, mallets, and bill-hooks, slaying all before them. Thus they came to the second battalion that had been posted in the rear of the first; and the archers followed close king Henry and his men-at-arms.
We shouldn’t take these too literally, e.g. the fact that the foot received an order by trumpet, but the archers did not shouldn’t necessarily be interpreted to mean that nobody told the archers to engage in the melee, but overall, I think this shows a battle where there are some very general and straightforward instructions given from command to the soldiers, but nothing more detailed. Nobody is standing next to the archers saying ‘ready, aim, fire’ for every shot. | [
"It is believed to come from the military \"beware before\", which an artilleryman who was about to fire would yell, alerting nearby infantrymen to drop to the ground to avoid the shells overhead. (\"Before\" may mean \"in front of (the gun being fired)\"; \"fore\" may mean \"(look) ahead\".)\n",
"In the context ... |
If cosmic microwave background radiation is traveling to us from a little after the Big Bang, at the speed of light, then how did we get here first? | The big bang wasn't an explosion in space at a point, away from which we're now flying. It was the expansion of *all* of space. For several hundred, thousand years after the initial singularity, the universe was too hot and dense for light to travel. Any time it was produced, it would immediately be absorbed by something nearby. But around 370,000 years after the initial singularity, the expansion caused the universe to cool sufficiently that neutral atoms were able to form. When that happened, light was emitted from *everywhere* in *all directions*. The light we're seeing as the CMB today comes from points that were so far away at that time that their light has taken 13+ billion years to reach us. Light from closer points passed us earlier, and light from more distant points will reach us eventually (except for some *really* distant points from which light may never reach us). | [
"The discovery of microwave cosmic background radiation announced in 1965 finally brought an effective end to the remaining scientific uncertainty over the expanding universe. It was a chance result from work by two teams less than 60 miles apart. In 1964, Arno Penzias and Robert Wilson were trying to detect radio ... |
how do you lift 'with your legs' and not with your back | Basically you want to keep your spine, from the small of your back to your neck, as vertical as you can.
Keep your back straight and your head up, bend your knees to lower yourself until your hands can grip the load. Then straighten your legs to stand up again and walk away with the load.
[Some good images](_URL_0_)
| [
"The pulldown usually uses a weight machine with a seat and brace for the thighs. The starting position involves sitting at the machine with the thighs braced, back straight and feet flat on the floor. The arms are held overhead at full extension, grasping a bar connected to the weight stack. The movement is initia... |
what is political correctness? | In a nutshell, political correctness is a way of speaking, behaving, and expressing oneself that deliberately focuses on having no negative implications towards any one or group of people. It's designed so that no one is offended and to let other people know that you have considered all people and perspectives in what you are saying. People get upset because it's not a realistic way of communicating and using it makes it seem like you are being less than honest. | [
"The term political correctness (adjectivally: politically correct; commonly abbreviated PC) is used to describe language, policies, or measures that are intended to avoid offense or disadvantage to members of particular groups in society. Since the late 1980s, the term has come to refer to a preference for inclusi... |
If quantum computing is a possibility, is there also such a thing as quantum storage? | As for long term storage devices for [entangled states](_URL_1_), none exist. It is ridiculously hard to preserve entangled states for longer than a few seconds. Currently though, the quantum information processing community is working on something called [quantum memory](_URL_0_) that would allow a device called a [quantum repeater](_URL_2_) to store entangled states for a few seconds. For these devices though, the storage time doesn't need to be very long, just long enough to do some classical processing. | [
"A quantum computer is a device that uses quantum mechanisms for computation. In this device the data are stored as qubits (quantum binary digits). That gives a quantum computer in comparison with a conventional computer the opportunity to solve complicated problems in a short time, e.g. discrete logarithm problem ... |
How different was Mao's communism from Marx's commuism? What about the Russian figureheads like Stalin, Trotsky, or Lenin? | One of the biggest difficulties with this is that Marx is a little light on Revolutionary theory, so much so that philosophers and historians still disagree about whether he advocated violent revolution or not. The Communist Manifesto is a slim thing, about thirty or forty pages, and is decidedly inevitablist in its tone. Marx's larger works, like Capital, are longue durée economic histories of the concentration of power into the hands of one class in Europe. Personally, Marx would probably have been deeply dismissive of Maoism--especially for its reliance on the peasantry, a class which Marx viewed as backwards. Marx also believed that Communism would only emerge in countries in the most advanced stages of industrialism--hardly the picture of early twentieth century China.
The entire transitional stage between capitalism and communism, the stage which the PRC and USSR hypothetically occupied, is often called the “dictatorship of the proletariat"; Marx says almost nothing about this stage--the theory of a transitional period was largely developed and popularized by Lenin and other Bolshevik thinkers.
Maoism is, frankly, a fairly crude implementation of Marxist (really Marxism-Leninism) theory. Mao does not seem to have been a particularly heavy-hitting ideologist, as opposed to Zhou Enlai. Maoism basically consists of four principles: People's War, New Democracy, Cultural Revolution, Three Spheres (or worlds) theory. Practically, these translate to tight state control of all industry for the purpose of preparation of war against “imperialist" powers. Maoism departs from other socialist theories by its intense focus on agricultural collectivism and the use of the peasantry, as opposed to the urban working class, as the engine of the revolution. | [
"Mao Zedong famously declared that Stalin was 70% good, 30% bad. Maoists criticised Stalin chiefly regarding his view that bourgeois influence within the Soviet Union was primarily a result of external forces (to the almost complete exclusion of internal forces) and his view that class contradictions ended after th... |
Why does 5 hour energy contain 8000%+ vitamin B? | Since it is water-soluble, it just gets flushed out in your urine pretty quick. The whole process takes about... 5 hours! Which makes me wonder what kind of trickery those "6 hour power" guys are up to.
Fat-soluble vitamins *can* accumulate. Too much of them can lead to [hypervitaminosis](_URL_0_) | [
"The official website lists the active ingredients of 5-hour Energy as: vitamin B6, folic acid, vitamin B12, sodium, taurine, glucuronolactone, malic acid and N-Acetyl -tyrosine, -phenylalanine, caffeine, and citicoline. The product is not U.S Food and Drug Administration approved. It contains no sugar, instead pro... |
if the court sides with the defendant, why are they still responsible for lawyer fees ? | Because it would encourage parties to make litigation less efficient. If I have to pay for my defense I'm less likely to want my attorney to file a ton of unnecessary motions. That's assuming the lawsuit is not frivolous. Though they could potentially collect in a suit responding to this one, such as a defamation of character suit. | [
"Even though it is possible, it is rare for individuals to fund their own personal injury claims by retaining a lawyer on an hourly basis. In some jurisdictions, if the client's claim is successful, the client will be able to recover attorney fees from the defendant. In jurisdictions that follow the American rule f... |
Good historical movies for ancient/classical times? | Unfortunately, antiquity is very poorly depicted in television and film. I personally cannot think of any film set in antiquity that accurately depicts it’s setting. I do apologize for the short answer, but there really are none. Might I ask why you are looking for films that are “pinpoint historically accurate?” In general, film is a rather poor medium to use to understand a historical time period, especially antiquity. As an entertainment medium, plot and character development are normally given precedence over historical accuracy. Your best option are books, and there are numerous scholarly introductory texts for most topics in ancient history. | [
"The film is also notable for its unusual time period: The time following Alexander the Great’s death (323 BC) but before the rise of the Roman empire (27 BC), known as the Hellenistic era. Most sword-and-sandal epics of the 1950s and 1960s were set in either classical Greece or even earlier (\"Hercules,\" \"Ulysse... |
why does it seem that u.s. construction projects, roadwork, etc. take so long to complete while in other countries it appears to be much shorter? | My dad is a project manager for a developer. I asked him this question a few weeks ago. Here's what he said:
I would think it is a combination of a lot of the items the article mentioned plus many other items. There is a current lack of skilled labor which is forcing contractors to work overtime to complete projects. Also, our government regulations and review, paperwork processes keeps getting worse. The states control many of these projects but they have to meet federal guidelines to get federal funds. Double government control. Double the paperwork to get plans approved and get paid. Doesn’t help. (I have a small project right now for 1000’ of new city sewer. I need Delaware City, Delaware County, Orange Township, Army Corp of Engineers, and OhioEPA approval. And I’m paying for the work, no government funds.)
One thing that was mentioned many years ago. Public projects here are awarded to the lowest bidder because of the government. However, in much of Europe and Japan, they are awarded to bidders who provides best warranty. More care taken to complete work and much less work needed to make changes because you can reuse existing base. May cost more to build initially in Europe, but much lower costs in future. Low bidder here figures they will make it up on changes. In US, we don’t care because we will just replace it… Lower bidder has to make profit so they hire lower skilled and less productive.
There is a culture growing in construction trades to care less about others work. Trade A (electrician) doesn’t care about another Trade B(plumber)'s work. If Trade B does something that is in way of Trade A, they just cut through it and then don’t tell anyone. Eventually Trade A has to come back and fix. And at end of day, they don’t finish what they are doing, they just leave. Then next day they have to inevitably rework some portion of work they did yesterday.
And I think our geography may play a role. Workers have to travel further because we are much more spread out. Makes for unhappy workers which equals unproductive workers.
| [
"The American Recovery and Reinvestment Act of 2009 created over 12,600 road construction projects, over 10,000 of which were in progress as of 2010. Workers in highway work zones are exposed to a variety of hazards and face risk of injury and death from construction equipment as well as passing motor vehicles. Wor... |
what does is feel like to have a seizure? | There are many different types of seizures, all of which probably feel very different. But, I can tell you about the one I had.
I was sitting at the computer and everything suddenly started tilting and sliding. From my perspective it was like the entire room just suddenly tilted and slid to the right. Looking back later, I realize that I was falling out of my chair, but I couldn't feel my body so I didn't know I was actually falling.
One of my relatives was there and I remember seeing his face above me (I didn't know at the time, but I was lying on the ground). I desperately wanted to tell him that I was okay, so I tried forming the words, but I couldn't say anything. In that moment I felt terrified because, if I couldn't even *say* that I was okay, clearly I was not okay, and something was horribly wrong. I remember that I couldn't even tell if my mouth was open or closed, or where anything was, it was incredibly confusing. I later learned that my relative had stuck his hand in my mouth to prevent me from swallowing my tongue (which is not actually recommended now, I don't think, but was something he had heard to do).
To this day I don't know if I was just laying there completely still or if my body was seizing and thrashing around. I never asked, no one ever told me, and I had no feeling in my body for the entire episode. It lasted about thirty seconds, probably. This happened over ten years ago so the memories are probably a bit fuzzy. | [
"A seizure, formally known as an epileptic seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with loss of consciousness (tonic-clonic seizure), to shaking movements involving... |
Are the different regions of the brain physiologically different? | The answer would be "both": the cells are different, and the ways they are connected to each other are different.
Even in the cortex (you know, [that wrinkled walnut-looking stuff](_URL_3_) that you first imagine when you think about human brain): even in the cortex, although it looks pretty uniform at the first glance, cells in different regions are actually somewhat different. [Look at this picture](_URL_1_): motor cortex has to send signals down to the body, so it has lots of large cells that can grow long "cables" running down through the spinal cord. The visual cortex, on the contrary, receives information, and has to have lots of small cells to quickly process it.
And if you go to other brain regions (you mentioned brain stem, for example), the differences only get greater. [A cell in the cerebellum](_URL_2_) - the part you use to learn and perform fine movements, would be very different from [cells you use to recognize different smells](_URL_0_). No wonder, right?
Also, on top of that, two cells that are similar in shape, can actually function pretty differently depending on their molecular machinery. They would react to different chemicals, release different chemicals, transmit electric signals differently... And indeed they would be different in different parts of the brain. Those cells in the brainstem that are responsible for your breathing have chemical sensors to detect that you haven't inhaled for a while, and it's about time to do it. Cells in a small nucleus in another part of the brain don't care about your breathing, but change their properties twice a day, there and back, controlling the way you get sleepy at night, and then get awake during the day.
Yet at the same time, fundamentally, these are all neural cells, and they share lots of basic properties between them. In most cases, the most important thing is that they are connected differently. But then, on top of that, they are often fine-tuned to support different functions. Makes sense? | [
"Some of the major anatomical components of the brain are organized as clusters of interconnected nuclei. Notable among these are the thalamus and hypothalamus, each of which contains several dozen distinguishable substructures. The medulla and pons also contain numerous small nuclei with a wide variety of sensory,... |
what does a cyber attack look like? | You don't find out until you notice something's wrong or someone tells you what happened. Two examples. Good malware doesn't let you know you have malware. If you notice something wrong, you take actions to remedy the problem... but if you never notice something logging all your password information and bank data, SSN or what have you when you type it in, then you won't notice until they use the information against you.
Second example, real world situation that happened at a family member's company. He works for a tech company. He's sitting in his office one day, when his secretary tells him there's an FBI agent who wants to see him. He talks with the FBI agent and it turns out while monitoring traffic between the US and China, they determined that rogue software at their factory in China was accessing their network in the US. Everything is networked so designs can be sent to the factory, but not so that a user at a factory can access military designs on other parts of the network in the US. The software was trying to break that. Turns out, a factory worker in china walked in with a USB stick and plugged it into the computer to install the software, and walked out and had not yet returned to retrieve the stolen designs. The FBI wanted the company to leave the security breach open so they could track where the data was going, be it to a private hacker group or to the PLA. Company said fuck that, we don't want to lose our designs to competitors in China so they closed it all off and fired the employee. Afterwards they established a "war room" at their headquarters in the states and hired a cyber security firm to better maintain their networks.
Point is, they never would have known without the FBI coming in to tell them.
You don't see a cyber attack, you notice its effects. | [
"The attack is spoofed, that is, random fake Internet source addresses are used, which makes it difficult to identify the attacker. The idea of the attack is to either degrade the performance of the attacked computer or make it crash. The attacking program is called Twinge, but the ICMP packets have a particular si... |
how movies like toy story had great graphics in the mid-90s, but video games took much longer to reach the same level of quality | Like MySuperLove said, once movies are rendered they're simply moving images.
Pixar and other production companies have render farms which are just a series of computers designed to render graphics like this. The computers process and render the images, and then the movie is made. It is put to film, and then projectors play it like any other movie.
Games, however, are limited by the computers of whomever is playing the game. These graphics have to be rendered in realtime. Because the images aren't processed in advance, it takes up much more computing power to show the images as they're happening.
Think of it like this: Render farms can spend several hours rendering one frame of a movie, making sure the details are nicely done and all that, because frames only need to be rendered once. Home computers need to spend *fractions* of a second rendering one frame so that as they are made on the fly, you see a picture moving at 60 frames per second.
As home computers got better and better, it's easier for games to take advantage of that and put more graphics intensive effects and polygons, etc. to make the games look better. | [
"Pat Ferguson, a video game industry analyst, called the game's character choices \"the great hook here,\" and stated that Sega \"has combined all the best of 16-bit video games in 'Jurassic Park.' The quality of the graphics is as good as it's going to get, and the sound is the highest quality I can recall in any ... |
out of everything that comes out of our body, what contains dna and what doesn't? | DNA is found in basically all of our body's cells (the major exception being red blood cells, which kick it all out so they can carry more oxygen). Off the top of my head, the main sources of DNA that you could leave behind are skin flakes, blood (in white blood cells), semen (sperm are basically DNA delivery vehicles), and mucus/saliva/feces (which contain a decent complement of skin cells in addition to a whole lot of microorganisms, which will have their own DNA). | [
"The human body is made up of billions of cells, each containing the unique genetic information, or DNA, that defines a person. Contained within DNA are instructions for making all the proteins in the human body.\n",
"Natural DNA is a molecule carrying the genetic instructions used in the growth, development, fun... |
what are the anti-eu parties across europe actually objecting to? | The combined currency is for some nations weaker than there own was, the freedom of movement and immigration laws see lots of people from poor eu countries moving into and living off welfare/stealing jobs from rich eu countries, bailing out stupid eu countries for making stupid decisions, the eu leaders for the most part weren't elected by the citizens of member countries (at least not directly) yet they can make laws that these citizens have to follow, countries with main exports of fishing/farming don't like the fishing/farming regulations and would rather regulate themselves than get regulated by a man in a desk in some other country, the list goes on.. | [
"Tensions between the EEU and the European Union (EU) occurred as both have sought to deepen their ties with several former Soviet republics. The EU has signed free trade agreements with Ukraine, Moldova and Georgia. However, separatists in all three countries back closer ties with Russia. Russia and the EU both pr... |
what does o(log n) mean exactly? | Its [Big O notation](_URL_0_) and tells you how processing time increases with a function of data size.
If something is O(log n) then processing time increases proportionally to the log2 of the size of the data. If you increase your data by a factor of 8 then processing time will quadrouple.
Big O notation is useful for determining the efficiency of an operation. If you have something that scales with O(n log n) then it will be fine for small amounts of data, but attempting to use it on a large amount will take an unreasonable time. [Here's a nice plot of the relative times of various Big O notations](_URL_1_), the green line in the middle is linear time. | [
"where \"log\" denotes a logarithm to base 10 or common logarithm, and \"K\" is a stepwise acid dissociation constant. For bases, the base association constant, p\"K\" is used. For any given acid or base the two constants are related by , so p\"K\" can always be used in calculations.\n",
"The noun \"login\" comes... |
how can we freeze molecules to almost absolute 0? | When you decrease the pressure of a gas, it will cool down. If you compress it, it'll heat up. So you can first compress a gas to a really high pressure, let it cool down, and then expand again - and it'll be really cold. Then you compress some of the cold gas again, and cool that down with the remaining cold gas to reach an even lower temperature. Rinse and repeat, until you have a tiny amount of liquid gas very close to 0K.
That's the easy part. To get very close to 0K, they use laser cooling: When atoms absorb a photon, they receive a bit of impulse, that means they are pushed a bit into a random direction. Normally that heats them up. But by using a few clever tricks with a laser, they can make the atoms only absorb photons when they are moving in the opposite direction of the photons. Each time this happens, the atoms lose a bit of their heat energy. This way, they can be cooled to around 0.001 Kelvin or even less.
| [
"Freezing is a phase transition where a liquid turns into a solid when its temperature is lowered below its freezing point. In accordance with the internationally established definition, freezing means the solidification phase change of a liquid or the liquid content of a substance, usually due to cooling.\n",
"A... |
in what way am i being fucked by my isp if my internet connection is considerably faster through a vpn connection? | Basically what's going on is your ISP sorts your internet traffic into different categories. Then they throttle back the bandwidth allocated to each category based on how important they think it is. So browsing imgur for example is likely going to be pretty far down on their priority list, and will be throttled back quite a bit.
With a VPN your internet traffic is still passing through your ISP, but because everything is being encrypted they can't tell what any of it is. Since they can't tell what category any of your data should be put in they just assume that it's all important and open up the flood gates for you. | [
"Setting up VPN services on a router requires a deep knowledge of network security and careful installation. Minor misconfiguration of VPN connections can leave the network vulnerable. Performance will vary depending on the Internet service provider (ISP).\n",
"In many cases, an ISP will have both a direct link t... |
What was taught at Oxford University during the first few years after it was founded in 1096? | [Oxford was not founded in 1096.] (_URL_0_)
That said, the basic curriculum for the average, bureaucracy-bound medieval university students in the 13th century consisted of the seven liberal arts, the *trivium* plus the *quadrivium*. The trivium was ~~dialectic~~ grammar, logic, rhetoric (essentially, ways of thinking and arguing in Latin); the quadrivium geometry, music theory, astronomy/astrology, arithmetic. Oxford also offered the three major advanced faculties for graduate students: law, theology, medicine. Another major use of medieval universities was to turn out students with a "license to teach"--essentially, educating and certifying friars (Franciscans, Dominicans, etc) to preach and teach the laity. They would generally follow their own curriculum. | [
"The University of Oxford has no known foundation date. Teaching at Oxford existed in some form as early as 1096, but it is unclear when a university came into being. It grew quickly from 1167 when English students returned from the University of Paris. The historian Gerald of Wales lectured to such scholars in 118... |
Most plants that live on the Earth's surface die without sunlight. But what happens if they are exposed to constant sunlight? | they grow quicker and bigger if in optimun soil. technically many annuals are tender perrenials and just keep growing. alaska for example has a short growing seasom but the nearly 24 hour sun in summer leads to huge growth | [
"Except for some parasitic plants, all plants need sunlight to survive. However, in general, more sunlight does not always make it easier for plants to survive. In direct sunlight, plants face desiccation and exposure to UV rays, and must expend energy producing pigments to block UV light, and waxy coatings to prev... |
I've heard that Russian tanks were immediately sent from the factory to the battlefield with ammo and men inside during WW2. How true is this? | Ok, so here's the list of main Soviet tank producing centers before the war:
* Moscow - plant №37 (produced light amphibious tanks - **T-37a**, **T-38**, **T-40**, ~4.500 total)
* Leningrad - plant №174 (in 1931-1941 produced light tanks **T-26**, total production ~10.000, and started light tank **T-50** production in 1941) and Kirovskiy plant (produced medium tanks **T-28** and heavy tanks **KV-1** and **KV-2**)
* Kharkov - plant № 183 - (produced all tanks of **BT** series ~8.000 total, all heavy **T-35** tanks and almost all pre-war medium **T-34** tanks), also have to be mentioned plant №75 (produced all diesel engines V-2 - tank engine for **T-34** and **KV** series tanks).
Stalingrad Tractor Factory is not mentioned, because it failed to become **real** tank factory before the war (only ~180 T-26 produced in 1933-1940 and ~200 T-34 in 1940-1941)
As you see, Russia had far more than one tank factory before the war, but wait, it gets more intresting.
Soviets started evacuation of industry, when German troops came close to those cities.
So:
* Moscow plant №37 was evacuated to Sverdlovsk.
* Leningrad plant №174 was evacuated to Omsk, Kirovskiy plant was evacuated in Chelyabinsk
* Kharkov plant №183 was evacuated to Nizhniy Tagil, plant №75 - to Chelyabinsk.
Despite the evacuation said factories kept production and repairment of tanks with remaining facilities (for example some T-35 tanks were still repaired in Kharkov, when city was captured by Germans in October 1941).
Stalingrad Tractor Factory became important during late 1941-early 1942 (when evacuation of other factories haven't been complete yet) as main production center of T-34's. Leningrad was blocked and it was impossible to send off KV tanks anywhere but to defend Leningrad.
Also Soviets started production of T-60 tanks (mainly composed from automobile parts) on GAZ car factory in Gorkiy, plus another factory in Gorkiy - №112 started T-34 production in 1942. Uralmash factory in Sverdlovsk started T-34 production, also Moscow plant №40 was converted to SPG production.
So in 1942 there was tank production in:
* Chelyabinsk (Kirovskiy plant + plant №75) - **KV** tank series + SPG's.
* Nizhniy Tagil (plant №183) - **T-34** tanks.
* Omsk (plant №174) - **T-34** tanks.
* Sverdlovsk (Uralmash - **T-34** tanks, plant №37 - SPG's).
* Stalingrad (Tractor Factory) - **T-34** and **T-60** tanks. Despite German advance, production stopped only in September when Germans broke through to the factory.
* Gorkiy (GAZ - **T-60**, **T-70** tanks and SPG's, plant №112 - **T-34** tanks).
* Moscow (plant №40) - SPG's.
I hope it answers the question about "only one tank factory", and i'm not even mentioning numerous factories, converted into tank repair plants all over the Russia.
About sending tanks from the factories immidiatly to the front line. I hope you understand that before shipment those tanks were properly tested first, each factory had its own shooting range, for example. But sending tanks to the battlefield implies that tank crews patiently waited for these tanks to be produced at the factory, and this is BS.
Probably it was true for Leningrad and Stalingrad - close proximity of the front line kinda suggests it (i'm not even talking about impossibility of sending tanks somewhere else in case of Leningrad and Stalingrad in August-September 1942). It would also be true for any tank-repair facility in close proximity of the front line (it's kinda logical to send tanks in need of repairs there, isn't it?).
No idea about rebuilding some factory brick to brick though, sorry. | [
"Beginning from 1941, 1,386 M3 medium tanks were shipped from the USA to the Soviet Union, with 417 lost during shipping (when they went down with their transporting vessels which were lost to German submarine, naval and aerial attacks en route). These were supplied through the American Lend-Lease program between 1... |
Do people with a fast metabolism have more mitochondria or do the reactions happen quicker? | I think you have the idea of metabolism slightly misunderstood. Metabolism, in most peoples understanding, is how much food you can eat and not gain weight. Whereas metabolism, in scientific terms, is the overall production and expenditure of energy through the deconstruction and construction of compounds throughout the body.
Metabolism is divided into two main categories catabolic and anabolic.
Catabolic is the breakdown of compounds to create energy which is the cellular respiration part of it.
Anabolic is the synthesis of new compounds (proteins, carbohydrates, fats, and nucleic acids).
The common understanding of metabolism is based off of the Metabolic Rate which is generally measured by how much energy the anabolic processes require over time. So cellular respiration doesn't technically mean a "fast metabolism" because it is simply the creation of energy whereas you should be looking for the consumption of energy.
This is vastly generalized because understanding the metabolism as a hole is very complex. | [
"It is worth noting that there are not many kinetically perfect enzymes. This can be explained in terms of natural selection. An increase in catalytic speed may be favoured as it could confer some advantage to the organism. However, when the catalytic speed outstrips diffusion speed (i.e. substrates entering and le... |
Does masturbation make one sleepy like sex? | Masturbation, or more specifically an orgasm. Is a very energy intensive process for the body, from flooding the body with hormones to producing bloodily fluids, not to mention the raw physical exertion. All these factors add up to make the body more "tired" than before the process. Also endorphin is released which I believe help the sleeping process? I don't know for sure about that one though. | [
"Sleep-related abnormal sexual behavior, \"Sleep sex\", or sexsomnia, is a form of confusional arousal that may overlap with somnambulism. Thereby, a person will engage in sexual acts while still asleep. It can include such acts as masturbation, inappropriate fondling themselves or others, having sex with another p... |
How do investigators determine that an individual was “killed instantly” in an accident? | The brain must be destroyed for someone to actually die instantly. When deprived of oxygen, e.g., from cardiac arrest or even decapitation, the brain may remain conscious for several minutes before unconsciousness sets in. We (I'm a former ER RN) tell everyone their loved one died instantly as a kindness, not because it is true. To your second question, if the individual is already unconscious, i.e., sleeping, they very likely remain unconscious until there is no more consciousness. If you get to pick, that's the way you want to go. | [
"Accident investigation may help to identify the cause of a specific accident. If a pattern can be identified this may inform procedures and legislation to reduce the risk of the same pattern of accident recurring in the future. An investigation may identify shortcomings in training or procedures, or problems with ... |
anisotropic filtering & anti-aliasing | Anisotropic filtering helps textures in video games to be viewed in more detail when they are viewed from an extreme angle [example 1](_URL_0_), [example 2](_URL_1_). Anisotropic filtering also helps to prevent aliasing.
The anti-aliasing method used in video games is officially called supersampling. It's a method for reducing the visibility of individual pixels at the borders of objects, also known as '[jaggies](_URL_2_)'.
| [
"An anti-aliasing filter (AAF) is a filter used before a signal sampler to restrict the bandwidth of a signal to approximately or completely satisfy the Nyquist–Shannon sampling theorem over the band of interest. Since the theorem states that unambiguous reconstruction of the signal from its samples is possible whe... |
mh17 is there a chance someone survived the initial explosion? | _URL_0_
This woman survived a 10k meter fall after a bomb went off on the plane. I'm not sure how different the effect of a bomb vs missile strike is, but in her case, it did break the plane in two. I think she was unconscious for the fall though, so no texting possible.
EDIT: Better explanation | [
"Lethal concentrations of carbon monoxide gas were found to be present. This suggested that the men lost consciousness rapidly and that death occurred within minutes. A public enquiry into the disaster took place, at No 2 Court of Newport Civic Centre, between 19 and 28 September 1960. The Inspector of Mines report... |
why does it sound terrible if two songs play at once on one computer? | A speaker produces sound from a very simple physical movement, and this movement can only contain a finite density of "information". The computer will collect all sound output and sum them together into a single wave pattern that it will instruct the speaker to perform. The wave signal created by the computer is the best estimation it can do for a wide variety of pitches and frequencies, and understandably, it has to distort and approximate in order to include as much of the sound output as it can. When you have two full-bodied audio clips playing at the same time, each with a complex range of tones and pitches summed into one whole, the single speaker may not be capable of producing such minutely detailed soundwaves. The distortions and estimations to make up for the loss in data from the signal to the output of the speaker is what you're perceiving as "BLEHHH".
The quality of the speaker obviously influences how much audio detail it's capable of, but ordinary laptop speakers really aren't capable of much
Adding more speakers doesn't always help with sound quality either. Your computer will need software that utilizes the number and quality of speakers intelligently. Surround sound is a simple example. If you have four speakers in four corners of a room, and you play a simple youtube video, all four speakers will emit the same audio signal. But if you play a DVD that has surround sound capabilities programmed into the file, your computer will be instructed on how to construct multiple sound signals to play for their respective speakers. So if you have two sets of speakers, and you want to play two different songs at once, you'd need software to tell your computer not to just sum up both songs and play from all speakers, but to divide the songs between the two speakers.
EDIT: Added in more explanation about software | [
"We haven't lost the song. We played it too much in a certain way that didn't work in my opinion. It didn't feel right. So we need to approach it in a different way, but at the time of \"OK Computer\" it was impossible to get into rearranging it because everyone had fixed ideas on what to play and we'd all just got... |
where did Anglo-Saxon churchmen get the red wine they used for the sacraments? | Actually England had vineyards for quite a long time. The domesday book even noted that there were vineyards in the north. But that wasn't a new thing, they also had vineyards during the roman period. Monasteries, in particular, had a great deal of wine on hand.
Here are a couple of podcast episodes on the Anglo Saxon drinking culture.
[Anglo Saxon Drinks](_URL_1_) and [Anglo Saxon Drunks](_URL_0_) | [
"In Eastern Christianity, sacramental wine is usually red, to better symbolize its change from wine into the blood of Jesus Christ, as is believed to happen at the Eucharist. In the Eastern Orthodox Church, for example, sacramental wine used in the Divine Liturgy must usually be fermented pure red grape wine, often... |
why are smokers often berated but there is a movement for fat acceptance, basically promoting obesity? | Smoking harms the user.
Obesity harms the user.
Smoking causes damage to unwitting public by proximity.
Obesity does not, except in cases of momentum and gravity.
Smoking is not needed for survival.
Eating is.
Big Tobacco forgot to maintain their political contributions.
Big Food has not. | [
"The obesity paradox has been criticized on the grounds of being an artifact arising from biases in observational studies. Strong confounding by smoking has been noted by several researchers. Since smokers, who are subject to higher mortality rates, also tend to be leaner, inadequate adjustment for smoking would le... |
"the netherlands is the world's second-largest exporter of food and agricultural products, after the united states". how on earth is this possible? | Well, on top of what others have suggested about Rotterdam being one of the larger trade hubs in Europe it's also because growing crops is really a thing in the Netherlands. They do grow a lot of crop. Really. They do. It's a nation well suited for growing things. Easy access to water, and pretty flat ground with mostly healthy soil.
A substantial lot of the greenhouse-growable crop that is consumed in Europe is *originating* from the Netherlands. It's not only traded there, but it is by tradition grown there. It's pretty obvious that the best way to access a market is to go to the place where most of the trade would have happened anyway, so that is what both buyers and sellers do. And as a result, they inflate the importance of the market there.
You can grow peppers outdoors in parts of Europe, but you can also grow them in a greenhouse in the Netherlands. And if you grow them in a greenhouse, you can control the growing environment in a way that makes it possible to harvest some volume every day. all year around. If you want to up the volume, all you need is to up the amount of plants and the volume will follow. Most crops that grow outdoors get two or three harvests a year, there is no way a natural growth can compete with greenhouse growth that outputs every day. It's for practical purposes the same product. One producer sells every day, with a very predicted volume. The other sells twice a year with a high-risk, weather-conditioned volume. It's not really hard to predict who is gonna sell more and if I'm to guess who has the closest relation with the market I'm gonna guess it's the greenhouse owner who talks to his buyers every day. | [
"The Netherlands has, at some time in recent history, supplied one quarter of all of the world's exported tomatoes, and trade of one-third of the world's exports of chilis, tomatoes and cucumbers goes through the country. The Netherlands also exports one-fifteenth of the world's apples.\n",
", the key trading par... |
Several times on Reddit, I've seen claims that Johan de Witt was eaten by a mob of angry Dutch. Is there any support in the primary sources for this claim? | well, there's [this](_URL_0_) contemporary publication of several eye-witness accounts and a letter by a judge. I haven't read the whole thing but it does mention people biting the corpses and cutting off pieces with the intent of eating them (so they said). To say that he was entirely eaten would be exaggeration though (the truth is gruesome enough).
> [...] sneet den Ruaerd een stuck vlees uyt het lyff omtrent sijn heupen, seggende voorgenomen hadt het selve dien avondt met den Chirurgyn Tichelaer noch te gaen braaden ende te eten. (p. 22)
In (my) translation:
> [...] cut a piece of flesh from the steward's* body, about the hips, saying he planned to roast and eat it that night, with the surgeon Tichelaer.
*Cornelis de Witt, Johan's brother and fellow victim, was steward (i think that's the right translation) of Putten. | [
"Shortly following the publication of his article, Trevor-Roper began to retreat from these charges. At the time of his article, Kersten had just been nominated by the Dutch government for the Nobel Peace Prize for thwarting a Nazi plan to deport the entire Dutch population, based primarily on Kersten's own claims ... |
what is a gifv, why does it stop background music on ios, and what's wrong with a good ol' gif? | "Gifv" is specific to Imgur. Instead of playing the Gif normally, it converts it (well it's already converted) to WebM, a video format. iOS automatically pauses background audio whenever a video file is played, whether or not the video has audio. | [
"GIFs are another example of remix culture. They are illustrations and small clips from films used for personal expressions in online conversations. GIFs are commonly taken from an online video form such as film, T.V. or YouTube videos. Each clip usually lasts for about 3 seconds and is \"looped, extended and repea... |
After a nuclear detonation, why do rings appear sometimes around the mushroom cloud? | They're called Wilson clouds, and they're caused by the shockwave of the explosion.
The pressure front of an explosion causes a decrease in pressure to occur behind it. This is intuitive to anyone who has ever made a wave in their bathtub: in a closed system like the atmosphere, any increase in density somewhere has to correspond to a reduction somewhere else. With a gas, a decrease in density translates to a decreased temperature: this is another effect that you can witness for yourself by playing with compressed air: as the pressure inside the can is reduced by venting the compressed air, it rapidly cools. This is the same mechanic used by refrigeration systems across the planet.
On a large scale explosion like a nuclear detonation, the power of the shockwave can cause *substantial* cooling of the atmosphere, dropping it below dew point. When this happens, the humidity of the air condenses into water droplets, forming the ring clouds that we see around the explosion. | [
"Mushroom clouds are formed by many sorts of large explosions under earth's gravity, but they are best known for their appearance after nuclear detonations. Without gravity, the explosive's by-product gases would remain spherical. Nuclear weapons are usually detonated above the ground (not upon impact, because some... |
the state of illinois hasn't had a budget in over two years. what has all of our money been doing during that time since taxes are still being collected? | This is a question I'd love to see answered. My understanding is that there are ongoing operational expenses that are being funded by our taxes--like the necessities of day-to-day state government functions. A huge portion of our taxes go toward paying interest on the enormous debt that the state has.
I would think that even the debt alone could eat up IL's tax revenue for years. | [
"In December 2015 the state of Illinois had had no budget in place for over five months. On December 9, at the City Club in Chicago, Madigan publicly said he thought the state income tax should increase to \"at least 5 percent to balance the state's out-of-whack finances\".\n",
"In past years, the state of Illino... |
When something is known to "cause cancer," what exactly does that mean? | We rarely talk about things that "cause" cancer outright. Carcinogens cause damage to DNA. Since it takes several independent mutation events to transform a cell from a normal one to a cancerous one, a carcinogen can only increase the *risk* of developing cancer.
Investigating a proposed carcinogen usually starts with establishing correlation. "People exposed to lots of radiation tend to develop cancer more often." From there, you look for a mechanism. "Radiation causes breaks in the DNA backbone which lead to mutation events."
What do you mean by "we hardly understand the nature of cancer" ? | [
"When cancer begins, it produces no symptoms. Signs and symptoms appear as the mass grows or ulcerates. The findings that result depend on the cancer's type and location. Few symptoms are specific. Many frequently occur in individuals who have other conditions. Cancer is a \"great imitator\". Thus, it is common for... |
During World War II, did the Allies open the western front to prevent the Soviet Union from conquering western Europe? | > I found this interesting because, if true, it would pretty significantly change my interpretation of the Allied invasion of western Europe. The typical narrative is that the Allies invaded France and Italy in 1944 in order to increase the pressure on the Nazis and to relieve the pressure for the Soviet Union on the eastern front. This doesn't really make sense if it was known that the Soviets had essentially defeated the Nazis by the end of 1943.
To say that would change your interpretation would ignore the fact that the Western Allies had been fighting in North Africa (Operation Torch and the ensuing North African campaign) since November 1942, less than a year after the United States had entered the conflict.
And it would also ignore the fact that the Allies invaded Sicily in July of 1943, as well as Salerno in September of that same year. The ensuing Italian campaign tied down well over a million men total from both sides.
Thus the Allies had been involved in the West in trying to open a second front within a year of the United States entering the war.
*The Second World War in Europe: Second Edition* by S.P. Mackenzie discusses in brief about Operation Sledgehammer - the proposed invasion of Europe in 1942 by the United States which was rejected by the British. The British feared a repeat of Gallipoli of World War I and the weakness of unproven American forces.
Keep in mind too something that we take for granted in the modern age where the United States is a global military power capable of projecting force to any corner of the world: in 1942, the only way to get troops and equipment like tanks and aircraft across the oceans was via transport ships.
To build up the necessary personnel and equipment - everything from tanks to trucks to oil drums to engineering equipment - in order to sustain a fight on Western Europe that would require *millions* of men would take years to do.
So the planning and logistics behind such an invasion was already in the works by 1942, before the war on the Eastern Front was decided.
Finally, the Soviet Union didn't have infinite manpower. Keep in mind that on the Eastern Front, the Germans fought all the way to the end in Berlin.
The Germans, however, were very willing to surrender to the Western Allies. This [AskHistorians thread](_URL_0_) discusses how entire German units fought their way west in order to surrender to the Americans and British.
[This post](_URL_1_) by /u/GTFErinyes has an interesting table at the end:
Over 8,108,983 German prisoners were taken in total by the Western Allies, including 3,050,000 taken before war's end while fighting was still going on in Berlin. That's roughly the same as what the Soviet Union took prisoner in their entire 4 year struggle against Germany.
That's a *staggering* amount of German forces that willingly surrendered to the Western Allies, and one can only imagine what kind of bloodshed would have happened had the Western Front never been opened and if Germans fought to the last man against the Soviet Union. The Soviets might well have won still, but it would have come at even greater cost and strain on Soviet society. | [
"In 1942, the Western Allies agreed to open a second front (the Western Front) in Western Europe to take pressure off the beleaguered Red Army in the Soviet Union. While Britain and the United States did not yet possess the resources to mount a full invasion, invasion plans that came to be known as Operation Sledge... |
why do online cable streaming services only show a select 4 or 5 commercials? | Is the ad rate so different than broadcast? I watch a local San Francisco station on-line and they have 4 ads. If I pay for broadcast ad rates why don'tI also get to have my ad showing on-line at the same time? | [
"They exist to allow network television stations to send content to smaller local stations. The shows contain no commercials, just a small gap of blank video to allow the local station to insert their own. The exception for this is for \"barter\" syndicated programming, where only the commercials required to be sho... |
During WW2, were there any naval battles in the Atlantic that involved American warships? | From an [earlier answer of mine](_URL_9_) also look at [/u/fourthmaninaboat's answer to the same question](_URL_10_) for some of the bigger naval actions.
Most of the USN's surface encounters with the European Axis tended to be very small-scale compared to the Pacific battles and often entailed units smaller than destroyers after the North African campaign. That said, there were some battles that did take place.
A good many of these actions involved German torpedo boats (S-boats, also confusingly termed E-boats in some Anglophone literature and also not to be confused with actual torpedo boats, which tended to be larger than the PT-boat-sized S-boats) or other small craft intercepting Allied naval traffic. The invasion of Southern France did witness two small battles between USN surface units and German ships. The American destroyer *Somers* on 15 August 1944 engaged with two ships the Germans had captured *UJ6081* (the former Italian corvette [*Camoscio*](_URL_4_) ) and *SG21* (the French aviso [*Amiral Sénès*](_URL_11_) and sank them both. An American surface patrol engaged the Kriegsmarine two days later off of La Ciotat with the destroyer *Endicott* and two RN gunboats sinking [*UJ6073*](_URL_1_) and [*UJ6082*](_URL_0_). There was a more serious encounter off of Imperia in the Ligurian Sea on 2 October 1944 in which the USN destroyer *Gleaves* tangled with three torpedo boats engaged in offensive mining operations. This night action though was confusing and neither side understood the other's intents; the *Gleaves* captain initially thought fire from the German ships was from shore batteries and the Germans' commander overestimated the size of the Allied enemy they were facing.
Not all of the American surface actions in European waters were responses to German incursions. There USN was involved in offensive patrols to break up or destroy German sea traffic in France. While RN ships outnumbered USN ones, the Americans were present in these offensive sweeps and interceptions. The Kriegsmarine's 24th Minesweeper flotilla operated in the waters of the Gulf of St. Malo and the German-occupied Channel Islands. The 24th's principle American opponents were PT Squadron 30 and PT Squadron 34 which operated out of recently-captured Cherbourg. These PT boats operated with larger destroyers and destroyer escorts, such as on the night of 6-7 August 1944 when the DE *Maloy* and PT503, PT500, PT507, PT508, and PT509 tried to intercept German minesweepers off of Jersey. The American attack was not successful and the task force lost [PT509](_URL_8_). Six days later the DE *Borum* and PT500 and PT502 engaged with the Germans again with indecisive results. *Borum* and her PTs took part in a mixed RN force outside of Guernsey on 13-14 August against a small force of four German minesweepers escorting a merchant ship. Again, this battle was indecisive showing the difficulty of engaging in nighttime coastal operations with a veteran force like the 24th. The Channel Islands remained in German hands throughout the rest of the war and its naval forces could still get a few licks in such as when the subchaser [PC-564](_URL_2_) had to flee four minesweepers when its gun jammed and she had to be grounded at Pierre de Herpin 8 March 1945.
PC-564 and PT509 were not the only USN ships lost to German surface attack. One of the more serious battles in the English Channel was the S-boat attack on Exercise Tiger off of Slapton Sands in April 1944. Tiger was part of the training and rehearsal for Overlord and consisted of eight USN LSTs and a RN corvette for escort. The S-boats attacked the heavily-laden LSTs, sinking two- [*LST-507*](_URL_3_) and [*LST-531*](_URL_6_)- and severely damaging two more. The cost of Slapton Sands was also quite severe with over seven hundred personnel lost and it caused minor concerns over security since some of the dead knew details of Overlord and it was not known if the Germans had picked some up as prisoners.
The S-boats also engaged with Overlord proper and the Cherbourg flotilla managed to sink a few USN LSTs and some other small craft. These attacks took place at night and were pinpricks to the larger Neptune fleet. Mines and obstacles were a greater threat to the Allied shipping in the region. German shore batteries, which were often manned by Kriegsmarine personnel, were responsible for the loss of the destroyer [USS *Corry*](_URL_5_) off of Utah beach and the same battery likely sunk the patrol craft [PC-1261](_URL_7_), which some historians consider the first Allied warship lost to direct enemy action in Overlord.
Overall, the USN's contributions to the Allied naval effort in European coastal waters was minimal outside of merchant shipping. The USN had some heavy units involved in the main operations, but they supplemented the largely-RN forces which did the bulk of the heavy lifting. Vincent O'Hara estimates of the thirty-eight major engagements (in this case, O'Hara excludes small craft attacks like S-boats), the Americans were present in less than five percent of the engagements, coming behind the Soviet Navy. But while battles such as Imperia were not nearly on the scale of Leyte Gulf or the Philippine Sea battles, they were real enough for the men who fought them. The battle of Slapton Sands was by some metrics the last significant Axis naval victory of the war; the Kriegsmarine managed to interrupt and Allied training exercise and extract a high number of dead with no losses of their own. But Slapton Sands remained an exception rather than the rule for the Kriegsmarine's last year and most of their engagements were not as one-sided. | [
"The North Atlantic was the site of a large-scale naval battle in 1943 between the United States and the Royal and French Navies, during which aircraft carriers were the principal weapons platform; the surface combatants never saw each other, as in our timeline's Battle of the Coral Sea. The U.S. won the battle, en... |
How does this "magic" mug work? | The phenomenon is called [thermochromism](_URL_0_). It involves changing the state or the structure of the dye molecule as a response to temperature change.
One way it is done is using a solvent with a high melting point, so when heat is applied the solvent is liquid, dissolving a dye and causing a phase change. Other techniques can utilize changes in pH, for example. | [
"A puzzle mug is a mug which has some trick preventing normal operation. One example is a mug with multiple holes in the rim, making it impossible to drink from it in the normal way. Although it is tempting to grasp the body of the mug covering the visible holes and drink the liquid in the usual manner, this would ... |
why are seemingly "blank" or "simple" pieces of art considered exceptional? | The history of art is a very long one and also one that is very complicated, but I think to appreciate art like this, you should have a little knowledge.
Paintings like the Mona Lisa, which was made in the 16th century, were made in a very different context than this black painting in the picture. 16th century artists were looking for the detail and attention to craftsmanship in their paintings, because that was what was considered the standard in the 16th century.
But art has evolved a lot since then, with a lot of artists questioning and rejecting past methods of painting. For example, the cubists (early 1900s, arguably the first painters to use abstraction) knew paint could only ever be paint, so there was no point in painting realistically in trying to convince the viewer that "hey, this is a real woman". That's why their paintings look all broken and geometric (think stuff like Picasso).
The abstract expressionists (around 1950s) weren't concerned with painting subject matter or depicting an object/model, they were concerned with feelings and emotions and they expressed that through paint (think stuff like Jackson Pollock). Some abstract expressionists tried to make the viewer experience an emotion through their paintings (think Mark Rothko or Barnett Newman). These guys looked at what paint could do, not what or who to paint.
Of course, I'm missing out on a lot of the political ties these movements had, and I've omitted whole chunks in history. But my point is that artists have become very open minded in their terms of what makes a painting- or even what makes a piece of art. And this open mindedness comes from an understanding of the long evolutionary history of art. But it sucks that the art world can be so exclusive and sometimes even elitist to the people who don't have an understanding of art history. So yeah, you do need a sort of developed perception to understand works like this. But again, you don't necessarily have to like it, even if you understand it.
| [
"In the course of the 20th century, nothing has become as distinctive an aesthetic category as “the beautiful”, “the ugly” or \"the absurd\". The artistic examination of the (non) phenomenon \"nothing\" has led artists and critics to question the traditional practices of art production and open up new possibilities... |
are radio waves as fast as the speed of light? then why is it stated that nothing can travel as fast as light, and/or that light (only) is the fastest thing that travels? | Things with mass can't travel at the speed of light. Radio waves *are* light, they're electromagnetic waves just like the light we see, but they have less energy. The same applies to microwaves, infrared, UV, X-rays and gamma rays, although the last three have more energy than visible light. | [
"In all these cases, however, there is no possibility that signals could be carried faster than the speed of light in vacuum, since the high value of does not help to speed up the true motion of the sharp wavefront that would occur at the start of any real signal. Essentially the seemingly superluminal transmission... |
What is the psychology behind using odd numbers as a price point for marketing of a product ? | I'm assuming you're referring to the tendency for items to be priced at something like $19.99 rather than $20.00. The guiding principle here is called left-digit bias. In essence, when we make valuation judgments, we preferentially attend to the leftmost digits (or rightmost, if that's where the most significant figures are in your culture).
It's a useful heuristic evolutionarily for making sense of numbers quickly, so it makes sense that we do it, but with prices it gets us into a bit of trouble. Even if we know that $19.99 and $20.00 are functionally equivalent, the non-numerated "cost" representation in our mind that influences the buy-nobuy decision is skewed just a little bit downward when the leftmost digit is a 1, rather than a 2.
Another way to think about this is in terms of how valuable we judge a thing to be, when we have a numerical reference which is *related to* it's value, but doesn't directly represent it. For example: the price we are willing to pay for a car, based on its odometer reading. From Lactera, Pope, & Snydor ([2012](_URL_0_)):
> cars with odometer values between 79,900 and 79,999 miles are sold on
average for approximately $210 more than cars with odometer values between 80,000
and 80,100 miles, but for only $10 less than cars with odometer readings between
79,800 and 79,899. | [
"In retail settings, \"psychological pricing\" or \"odd-number pricing\" are both widely used. Psychological pricing which refers to a range of tactics, designed to have a positive psychological impact. For example, price tags using the terminal digit \"9\" (e.g., 9.99, 19.99, or 199.99) can be used to signal price... |
What caused the New England countryside to turn against British authorities in the run up to Lexington and Concord? | As you rightfully point out, the origins of the resistance against the perceived overreach of the British government during the imperial crisis were based in the urban centres of New England where the different acts passed after 1764 had a greater impact. Now, it does need to be said that acts such as the Stamp Act *did* have an impact outside of Boston but not to the same extent. If we look at the simply question *why* anyone would rise up against the crown during the time period in question, we would find a wide variety of motivations in urban centres alone. Urban merchants had their own reasons for resistance against the crown while those of the "lesser sorts", whether it be waterfront workers, shoemakers, or apprentices had others that can't be ignored or discounted. Women and other oppressed minorities such as slaves of African or Native American descent had their own agency which they used not only to resist (or support) the crown, but also to resist oppressive structures in their immediate midst.
A good place to start with this inquiry is in the Boston Pamphlet and the creation of committees of correspondence. The Boston Pamphlet comes during a time of increased protest against the crown after two years of moderate hiatus after the Boston Massacre of 1770. For the sake of this answer, we will briefly focus on section B and C of the pamphlet. Section B is an overview of the perceived injustices by the British Parliament towards the people of Massachusetts. Predictably, the first two points in section B makes the claim that Britain is both passing laws and is imposing taxes without the consent of the people of Massachusetts. However, it was point 6 which not only prompted the creation of the Boston Pamphlet but which gives us an insight into what sort of question actually mattered to people outside of Boston: "Britain has upset the governmental balance of power by usurping the legislature’s authority to pay the salaries of the governor, lieutenant governor, and judges." In other words, the British Parliament has prevented the colonial assembly to perform its traditional role of paying the salaries of important officials (and thus making them answerable to the colonial assembly and therefore the people). This, the pamphlet states, "will, if accomplish'd, complete our Slavery." If the colonial assembly doesn't pay the salary for these important officials, including the governor and important judges, what would stop them (the officials) from being held answerable to the people and not take direct orders from Parliament? What would stop them from depriving men from their property, as in point 12 which states that Britain "has violated colonists’ property rights by granting to others land developed by settlers in the past, and by redefining colonial boundaries, thus forcing landowners at great inconvenience to recertify their holdings."
Section C, "A Letter of Correspondence to the Other Towns", suggests the creation of Committees of Correspondence throughout the Massachusetts Bay Province so that Boston could "communicate with our fellow Sufferers" about "this recent Instance of Oppression, as well as the many other Violations of our Rights under which we have groaned for several Years pasts." The Boston Pamphlet created a popular response in town meetings throughout the province. Although only men with property could attend these meetings, they made up a big portion of men in rural Massachusetts seeing as many owned farms which were seen as a symbol of self-determination. Hundreds of Massachusetts town answered in the affirmative by creating their own Committees of Correspondence. Lexington for example answered with a statement that stated that they looked "upon themselves in common with their Brethern and Fellow Subjects throughout the Province, to be greatly Injured and Oppressed in Various Instances by Measures of Government lately adopted."
1772 was only the beginning but it established a line of communication between the urban center of Boston with the greater Massachusetts countryside. The crucial year, however, is 1774. Historian Ray Raphael is the scholar who has really explored this particular period out of the perspective of the Massachusetts countryside and I would refer to his book (see sources) for a more in-depth explanation. During the lead-up to the Boston Tea Party, there were already tea boycotts and protests against the unconsented taxation in the Massachusetts countryside. the After the infamous Boston Tea Party in December 1773, the British Parliament introduced a series of acts (The Coercive Acts or, as they were known by some, the Intolerable Acts). Although the Boston Port Act is arguably the most well-known of these, it was the Massachusetts Government Act which would play a vital role in putting the Massachusetts countryside aflame. The Massachusetts Government Act did not only practically revoke the Massachusetts Bay Charter but also deprived the people of Massachusetts from selecting town representatives (who would be selected by the governor and who would also appoint other important officials like judges) and from holding impromptu town meetings (that now required pre-approval by the governor).
Due to the large amount of enfranchised men in the Massachusetts countryside, 90 % in Worcester alone, this meant that a large portion of Massachusetts outside of Boston were effectively disenfranchised. This was not taken lightly by these rural towns. By October 1774, courts throughout the Massachusetts countryside had been forcibly closed down by the town militias. Citizens used intimidation tactics previously used in Boston to force officials to rescind their positions. In the Powder Alarm of September 1774, General Thomas Gage (also governor of Massachusetts) removed the provincial powder that was stored in the Powder House, in modern-day Somerville, in an expedition that triggered alarms throughout Massachusetts and led to the mustering of several militias that all marched towards Boston in belief that the British troops had fired upon colonists. The task of General Gage was to neutralize a rebellion before it happened. His attempt failed. By December 1774, the Massachusetts countryside had taken the initiative away from Boston and were now the leading the resistance against Great Britain. As laid out by many resolves by county conventions throughout Massachusetts, including the more famous Suffolk Resolves, rural Massachusetts were also preparing for war. If Gage once again sent out troops to impose the Coercive Acts on the people of Massachusetts, the men were ready to defend their self-determination through war.
**Primary sources:**
[The Votes and Proceedings of the Freeholders and other Inhabitants of the Town of Boston, in Town Meeting Assembled, 1772 \[The Boston Pamphlet\].](_URL_1_)
[The following extraordinary BILLS now pending in Parliament, arrived last Night in Capt. Williamson, in 36 Days from Bristol \[The Coercive Acts - as first published in Boston\].](_URL_0_)
**Secondary sources:**
The Revolutionary Worlds of Lexington and Concord Compared by Mary Babson Fuhrer in *The New England Quarterly*, Vol. 85, No. 1 (March 2012), pp. 78-118.
*The First American Revolution: Before Lexington and Concord* by Ray Raphael (The New Press, 2002).
*The Road to Concord: How Four Stolen Cannon Ignited the Revolutionary War* by J.L. Bell (Westholme Publishing, 2016).
*The Minutemen and Their World* by Robert A. Gross (Hill and Wang, 1976 [2011])
*The Glorious Cause: The American Revolution, 1763-1789* by Robert Middlekauff (Oxford University Press, revised 2007 ed.) | [
"News of the outbreak of war in Massachusetts, specifically the battles of Lexington and Concord and Bunker Hill, arrived in Argyle in the early summer of 1775. Most of the Argyle Planters were sympathetic to the rebellion; the Rev. John Frost preached a sermon in which he \"expressed his hopes that the British for... |
how is russia able to afford its current modernization program? | The available resource right in mainland and doesnt have to import, Russia with its vast land is very resource rich, so it's more cost-effective to self supplying some of the industries, making the product costs lower comparing to other countries. Furthermore, the cost living in Russia is lower than other western countries, although their social welfare isnt as good, but still acceptable in their own standard. And finally, being a somewhat "dictator ship", they can easily cut the money at some departments and transfer it to their higher priority one. It's the same with NKorea, where 60% people in starving thread, and still can launch rocket, although quality is questionable. Russia is way more bigger than NK, and has more experience in dealing with trouble from WW2. In motherland everything can happen. | [
"In 2009, former President Dmitry Medvedev launched the Medvedev modernisation programme, which aims to diversify Russia's raw materials and energy-dominated economy, turning it into a modern high-tech economy based on innovation. Following this, Russia's automotive industry has been in the spotlight due to its gre... |
Likelihood of seeing another "observable universe"? | It's better to think of the observable universe as the little geographic territory you presently live in. You know there's more earth beyond the borders of your (city,state,country) even if you can't see them from where you're at this moment. Granted it's a little bit different because it is, in principle, impossible to make any observations beyond our observable universe. (as it's the set of locations for which light and information traveling at the speed of light could possibly reach us in the age of the universe) | [
"BULLET::::- It is sometimes used, mainly by cosmologists, to mean the uncertainty because we can only observe one realization of all the possible observable universes. For example, we can only observe one Cosmic Microwave Background, so the measured positions of the peaks in the Cosmic Microwave Background spectru... |
How and when did Hinduism start? Does it predate Indus Valley civilization? | In my personal experience, 'Hinduism' is a highly syncretic religion, and you will often see various groups' beliefs represented in a temple. I've seen Mahavir (Jainism), Buddha, Siva and Vishnu all in the same temple.
As far as predating the IVC, the best answer for now is "we don't know". There were some indications that evidence would be found in [Cambay](_URL_0_), but I can't find any recent information about it.
The 'Aryan Invasion Theory' was a half-baked political idea based on a poor understanding of linguistics. It is the same relationship that "Social Darwinism" has to the theory of evolution. There simply is no definitive evidence to say that IVC was overrun by invading 'Aryans' who brought with them a new language and religion. | [
"Hinduism predates recorded history and is thought to have had a beginning over 7,000 - 9,000 B.C to 35,000 B.C, even before the Indus Valley Civilization itself. Exact date of emergence of Hinduism is unknown, But it traced back even before the Pre-historic period. Hinduism has no single founder; rather, it is a d... |
I know a lot of plants and animals have developed toxins as part of a defense strategy, but what about bacteria? | Microbiologist in training here!
Yes , bacteria, as fungi, have also developed chemical defense strategies, that can be a lots of things, like antibiotics, anti tumor or, as you said, toxins, etc..
E.g. Botulism is caused by a neuro toxin called botulinum, from bacteria from the genus clotridium. This substance is also used in very small doses in medicine : botox.
Hope I could help! | [
"Like other bacteriocins, vibriocins are protein toxins. They can kill bacteria beyond the genus Vibrio, including other proteobacteria. They have been used for abortive classification schemes of the vibrio, particularly to type various kinds of cholera, against which they were thought to have potential as antibiot... |
what is the difference between netflix's new releases and recently added? | Recently Added means that the content has only been added to Netflix's library recently but may have aired/been released on other platforms at any time before. New Release means the content has only been released on other platforms recently.
For example, if Netflix added a tv show from the '60s yesterday, it would appear on Recently Added but if they added a season of a tv show that aired earlier this year, it would be new releases. | [
"Netflix's DVD allocation policy – referred to by many as \"throttling\" – gives priority shipping and selection to customers who rent fewer discs per month. Higher volume renters may see some of their selections delayed, routed elsewhere, or sent out of order. Netflix claims that \"the large majority of our subscr... |
what causes some people to be more "addiction prone" than others? | There are several factors at play, and it seems to vary from individual to individual. The problem of addiction and alcoholism has been around for millennia, and we still don't have something we can point to, and say, "There it is. There's the problem, right there."
Genetics seem to have an influence. It can cause a tendency to be *prone* to addiction, but is not the causative factor. There are studies of identical twins, where one is addicted, and the other, not. There are also "black sheep" that come from a long and wide genetic history of normal intoxicant use, but these "black sheep" become addicts.
Dr. Gabor Mate, in his book "In The Realm of Hungry Ghosts" postulates that it is a combination of a genetic predisposition to addiction, triggered by environmental conditions, which may include trauma, such as sexual molestation as a child.
As time continues, and the consumption of intoxicants continues, it messes with the normal distribution of certain neurotransmitters, such as serotonin and dopamine. It is speculated that genetic vulnerabilities make this rewiring of the brain easier, and this is why some people are more prone to addiction.
As the addiction takes hold over time, its effects begin to manifest in the environment of the addict. They spend time with other addicts, and tend to damage their relationships with the non-addicted. If you become drunk and aggressive, you don't get invited to too many parties...unless everyone else at the party tends to get drunk, too.
At this point, the genetic tendency has been fully triggered, and the environment becomes one that fosters the consumption of intoxicants. The brain has become rewired so that pleasure by normal means is elusive, but can be had in an instant with another helping of the drug of choice.
Now the spectre of withdrawal sets in....and to break the cycle requires a complete overhaul of one's life, as well as suffering the physical symptoms of withdrawal. At this point the addict feels trapped, hopeless, and alone. Feelings of shame, remorse and self-loathing are common...and again, the only escape from them is another dose.
But there is some hope. It has been proven that participating in a community of recovery is beneficial to many addicts...indeed, most recovered addicts claim that the loss of a sense of isolation, the feeling of belonging to a fellowship, and the advice and support of other recovering addicts was instrumental in their recovery.
I am an alcoholic in recovery. My brain is wired in such a manner that the consumption of the smallest amount of alcohol creates a powerful, and virtually irresistible, craving for more. I can't open a bottle of rum, have 2 drinks, and put the bottle on the shelf. I just can't. I will drink until that bottle is empty.
Through my work in AA I have learned better patterns of behaviour. If I am feeling unsettled...lonely, stressed, anxious...I no longer reach for a glass, or a joint, or a line, or a pill to make me feel better. I have slowly brought the wiring in my brain to a more normal state.
But I don't fool myself. The changes made to my brain are permanent, and if I have one drink, I risk falling back into state of addiction. This is why so many people fall "off the wagon". They believe that a period of sobriety has provided a measure of control, and that they now possess the ability to moderate their consumption. In my personal experience, i have never met an addict or alcoholic that could PERMANENTLY moderate. Some manage to, for a time, but gradually slip back into a state where the neurotransmitters are only experienced with intoxication.
So, I guess the short answer to your question is, "Nobody knows. It's different for each addict." Personally, I find my life without intoxicants to be vastly more rewarding, and I am much happier.
And maybe that's the root of it. People take drugs because they are unhappy, and want to change the way they feel. The genetically predisposed quickly find themselves in a position where the brain has rewired itself to the point where happiness is difficult to achieve without the drugs.
For a better understanding of life as an alcoholic, [here](_URL_0_) is a post I wrote when I was just getting sober.
| [
"Some claim the existence of “addictive beliefs” in people more likely to develop addictions, such as “I cannot make an impact on my world” or “I am not good enough”, which may lead to developing traits associated with addiction, such as depression and emotional insecurity. People who strongly believe that they con... |
is the us actually at war with any government? | Not right now but we were at war with the Afghanistan government(Taliban) and Iraqi government back in the day until we got them out. | [
"This case is significant because it challenges the legality of being able to operate the military on a \"neutral\" site. This case emphasizes the proper role of the judiciary to refrain from deciding political questions that are for the President and Congress to decide. Congress has declared war only 11 times and ... |
how does the defrost on cars work? | The front or the back?
The front defroster works by blowing hot air on the windshield. The back window defroster works by pumping electricity through thin wires until they heat up. | [
"Resistive-heat defoggers are usually equipped with an automatic timer to operate for a set time period of 10 to 15 minutes before switching off. This is because most defogging is achieved within that timeframe, after which the vehicle's heater has usually brought the interior of the vehicle to a warm enough temper... |
Why did Rome never solve the "Persian Question" or vice versa? | They did. In 63 CE the emperor Nero and shahanshah Vologases after an indecisive war in Armenia hammered out an agreement by which the Parthians would select the king of Armenia and the Romans would crown him. This was an acceptable solution to all, as it maintained the Roman fiction of universal monarchy while tacitly acknowledging the closer relations between Armenia and Persia. Nero had correctly recognized that the earlier settlement, in which Rome had a much more direct role in appointing Armenia's ruler, was both pointless to Rome's true interests (ie, maintaining the fiction of universal monarchy) and detrimental to the eastern border, as Armenia had real practical importance for Parthia and, all else being equal, the Armenians rather liked their Iranian brethren more.
This arrangement worked fine for half a century until the reign of the aggressively expansionist emperor Trajan. technically, the agreement was broken by the Parthians, but I hold with those who think they did so because they saw the writing on the wall and hoped by shoring up Armenia they could force a repeat of Nero's war. That did not happen, but the rather anticlimactic war was followed by Roman mismanagement of the peace, followed by revolt in Assyria and a broader Jewish revolt. The momentum of Roman conquest was then utterly ended by Trajan's death.
In short, Nero and Vologases had hashed out a perfectly acceptable agreement that was ended through Trajan's aggression. | [
"Frequent Persian aggression during the 3rd century placed Roman defences under severe strain, but the Romans were eventually successful in warding these off and avoiding any territorial losses. Indeed, they eventually made significant gains towards the end of the century, although these were reversed in the mid-4t... |
why don't reeds work well on brass intruments and brass mouthpeices on woodwinds? | They both make vibration and therefore sound, but in different ways. On a woodwind mouthpiece, you blow air to vibrate the reed, while in a brass mouthpiece your lips are doing the vibrating. Both types of instrument (woodwind and brass) are designed to use the vibrations in different ways. The woodwinds change the pitch by opening and closing holes to for the air to whistle through, which requires a lot of moving air, while the brass change pitch by changing the length of the metal tubes for the vibrating air to travel through, requiring greater vibration.
tl;dr, woodwind mouthpieces don't vibrate enough to make brass instruments work, brass mouthpieces don't move enough air to make woodwind instruments work. | [
"With the woodwinds, aside from the flute, piccolo, and recorder, the sound is generated by a reed and not with the lips. The embouchure is therefore based on sealing the area around the reed and mouthpiece. This serves to prevent air from escaping while simultaneously supporting the reed, allowing it to vibrate, a... |
would greenland be properly inhabitable with fertile soil should all ice melt there? | Greenland has a base of volcanic rock so should have all the required minerals for plant growth, however there is no depth of soil require for plant growth, but eventually that could happen. | [
"The extreme north of Greenland, Peary Land, is not covered by an ice sheet, because the air there is too dry to produce snow, which is essential in the production and maintenance of an ice sheet. If the Greenland ice sheet were to melt away completely, the world's sea level would rise by more than .\n",
"Earth m... |
homelessness and skid row in la | Mental illness. Persistently homeless people tend to have mental illnesses and there aren't enough places to treat them, so they end up congregating together on the streets. | [
"Several of the city's homeless and social-service providers (such as Weingart Center Association, Volunteers of America, Frontline Foundation, Midnight Mission, Union Rescue Mission and Downtown Women's Center) are based in Skid Row. Between 2005 and 2007, several local hospitals and suburban law-enforcement agenc... |
when speaking about non-newtonian fluids, what is shear-thinning and shear-thickening? | Imagine having two plates with a fluid between them. When you move the plates there's a resistance put up by the fluid; less than if there were nothing lubricating the plates, most likely, but still some resistance.
In a Newtonian fluid the resistance scales linearly with speed: move twice as fast and you get twice the force.
When a fluid is shear-thinning you get scaling slower than linear: move twice as fast and you get less than twice the force.
When a fluid is shear-thickening you get scaling faster than linear: moving twice as fast means you get more than twice the force.
Cornstarch and water is a popular shear thickening fluid: at slow speeds it'll flow, but if you hit it hard then the internal friction in the fluid is enough to make it seem almost solid.
Ketchup is a shear thinning fluid: you smack the bottle to get it to start moving but once it starts moving it flows with lower resistance (although there's a lot going on mechanically when you smack a bottle of ketchup). | [
"In rheology, shear thinning is the non-Newtonian behavior of fluids whose viscosity decreases under shear strain. It is sometimes considered synonymous for pseudoplastic behaviour, and is usually defined as excluding time-dependent effects, such as thixotropy. Shear-thinning behaviour is generally not seen in pure... |
female voices are higher pitch than male voices, so why can you still hear the difference between a male and female voice when they sing the exact same note for example? | Good question! A tone is composed of more than just the base note. When you hear a tone, it is actually composed of the root note, called the fundamental, plus a bunch of higher frequency notes, called harmonics or overtones. When a man and woman sing the same note, they may produce the same fundamental, but their voices will carry different harmonics in varying ratios which produce their characteristic timbres. The same can be applied to any instrument. So even if a violin and saxophone play the same note, they will sound distinct because of the different harmonics. | [
"The pitch of a male voice is about half as high in males in comparison to females. Even after controlling for body height and volume, the male voice remains lower. Some scientists have suggested that human voice evolved through intersexual sexual selection, via female male choices. Puts (2005) showed that preferen... |
why do some websites say "webpage moved: redirecting in 10 seconds. click here to redirect now." why don't they just redirect immediately? | The actual redirect is being caused by a "tag" that the developer inserts into the code. They can customise it as much as they want, from 0 seconds to 100,000 seconds. But most developers choose 5 or 10 for two reasons:
1. It gives the user time to read the message (if they're interested) so that they *know* what is happening. Otherwise it may look like your browser has been randomly hijacked.
2. If you add an *instant* redirect, your "back button" becomes almost useless. Every time you try to go back, it will just *instantly* throw you forward again. | [
"BULLET::::- If a page redirects too quickly (less than 2-3 seconds), using the \"Back\" button on the next page may cause some browsers to move back to the redirecting page, whereupon the redirect will occur again. This is bad for usability, as this may cause a reader to be \"stuck\" on the last website.\n",
"So... |
why do "aids treatment breakthroughs" keep making it to the front page every week when all of them are nowhere near proven or relevant yet? | Welcome to science journalism. | [
"BULLET::::- Media coverage on AIDS begins to boom: outlets like \"Newsweek\" magazine and other major newspapers nationwide publish over 650 stories between December and April. Coverage included shortfalls of resources for AIDS research and education in NYC, and how the response in San Francisco was more effective... |
What causes ocean waters to rise in temperature? | Sea level rise is caused by the expansion of water itself as it heats up, and the input of water as glaciers and ice sheets melt. The melting of the glaciers and ice sheets are caused by increasing air temperatures. However, the vast majority of the heat is taken up by the oceans as the winds mix and the ocean circulates.
There are a multitude of cycles present within the Earth's oceans. These cycles can release heat back into the atmosphere or they can absorb more heat into the ocean depending on which phase they are in. ENSO (El Niño Southern Oscillation) is a good example. | [
"The extreme precipitation will cause the oceans to warm and acidify. The southern ocean will increase the most in temperature. The global mean sea levels will rise due to the extreme precipitation. Near-surface permafrost in high northern latitudes will reduce resulting in sea level rise not being uniform across r... |
if a neighbor blares music, why does only the bass sound pass through walls? | Sound is waves. High sounds are short waves and bass are long waves. It's not so much that bass is better at getting through walls but that high pitched sounds, meaning short waves tend to get more easily scattered.
Imagine a snake moving forward though a bed of rocks. If it slithers shorter the probability of it hitting a stone is higher than if it does very long slithers.
Also there's a bit of resonance. Sound actually makes your wall vibrate a bit. Even tho it's so subtle it isn't visible it's still far harder to make a wall vibrate 10000 times per second than only 15 times. | [
"Large bass speakers often take advantage of the surroundings as part of the horn. For example, they can be put in the corners of a room, so the walls act as part of the horn. Even outdoors, the ground can form part of the horn surface, and thus a partial horn can help provide a good impedance match to ground, or o... |
- how does remastering work? if the source material produces a blurry film 25 years ago, how do they make it clear now? | So film is actually very high resolution. Like, the actual material that movie cameras record on. If they can go back to those original high quality sources and then use modern technology to process them, they can get better results because modern tech can preserve more of the resolution that was still on that original film. | [
"Remastering is the process of making a new master for an album, film, or any other creation. It tends to refer to the process of porting a recording from an analogue medium to a digital one, but this is not always the case.\n",
"Purchased film content is downloaded onto an editing work station hard drive and thi... |
Arabic in Medieval Europe, how common was it and how did people learn it? | tl;dr - Overall, very rare.
The most important factor to keep in mind is *reason to learn*. For the vast, vast majority of medieval Christians, there was simply no reason to learn Arabic. They might know "pagan" Saracens existed, but that would be about it.
As you mention, OP, there were a few cases where Latin Christians would indeed have exposure to the Arabic-speaking world. The biggest group is probably not diplomats but *merchants*. There were European (mainly Italian) expat merchant communities in quite a few Mediterranean ports--Tunis, Cairo and Alexandria have been the focus of important scholarly work in the last few years. Merchants would likely (almost certainly) not have had formal instruction in Arabic, but it's reasonable to assume they learned enough to get along.
One case I'm *not* familiar with is the Crusader states in the Near East of the high Middle Ages. There is not a ton of evidence for mixing among the very small Latin populations with the original residents. But again, practicality may have dictated that people learn a few phrases of each other's language. Robert of Ketton was an English scholar who traveled *extensively* through the Near East, learning Arabic quite well along the way. He would eventually settle in Spain and translate the Qur'an into Latin around 1143.
As for formal instruction, there *were* a couple instances! You mention the Muslim communities on Sicily. It's true that some did remain after the Norman conquest, and indeed, the Normans enjoyed the extra taxes they could levy and didn't try to convert the Muslim population en masse. However, on one level they practiced a policy that led to the gradual isolation of the Muslim community, its eventual mass deportation to a colony on the Italian mainland, and their eventual wholesale expulsion. Alex Metcalfe, probably the foremost scholar on Islamic Sicily, speculates that there were a few bilingual Arabic-Romance communities, but (a) says the evidence is inconclusive and (b) says there is no evidence for what *kind* of bilingualism--meaning, people used one language daily but knew a few phrases in another; people moved in between languages regularly; etc.
The formal opportunity, though, came at the Norman royal court.
In the 12th century, the Norman administration in Sicily actually adopted Arabic as a prestige language! They were *very* plugged into the trans-Mediterranean world, drawing a lot more of their influence on governance/bureaucracy from Fatamid Egypt than from their Latin counterparts (twelfth century Europe is juuuust figuring out the business of governing instead of violent marauding). The Norman administration issued bilingual charters, with Arabic used as a show of power locally and also for practical purposes in diplomatic communications. Along with governance, the Norman court was also the site of major scholarly efforts at translating Arabic original and ancient Greek survival texts into Latin. Yes, there were Muslim scholars as well as Christians working at court, fluent in Latin as well as Arabic and probably a handful of vernaculars. /u/caffarelli - many of these "palace Saracens" were eunuchs!
At the same time the Normans were encouraging scholarly efforts at translation in Sicily, the courts of Iberia were fostering the same intellectual life. So you had Latin Christians learning Arabic formally there, too. There are a few hints of formal *studia arabica* (Arabic schools) established. The traditional modern understanding is that these were intended to teach future missionaries Arabic for conversion efforts, but more recent work has sort of undermined that idea--the Dominican and some Franciscan friars in North Africa, for example, were mainly there to minister to the expat European populations, not to convert the local Muslim residents. So if the studia arabica were just meant for people who would be working on translating texts, they'd have even more limited access.
Overall, there were a few formal opportunities for a very few, very educated, very elite Latin Christians to learn Latin. In the Mediterranean zone, exposure to Muslim communities may well have allowed more people the chance to pick up anywhere from a few phrases to practical bilingualism, maybe the equivalent of an English-speaking American with a telenovela addiction. International merchants and dedicated travelers (...mainly merchants, a few missionaries), still a pretty insignificant number overall, would likely have known enough Arabic to get by. But for the average European Christian, especially outside the Mediterranean zone, there was neither the opportunity nor the reason to learn Arabic.
Sources of Note: Alex Metcalfe, *The Muslims of Medieval Italy*; Jeremy Johns, *Arabic Administration in Norman Sicily: The Royal Diwan*; Georg Christ, *Trading Conflicts. Venetian Merchants and Mamluk Officials in Late Medieval Alexandria*; Robin Vose, *Dominicans, Muslims, and Jews in the Medieval Crown of Aragon* | [
"During the Middle Ages, Literary Arabic was a major vehicle of culture in Europe, especially in science, mathematics and philosophy. As a result, many European languages have also borrowed many words from it. Arabic influence, mainly in vocabulary, is seen in European languages, mainly Spanish and to a lesser exte... |
how commodities trading works. | Say you are a farmer who grows wheat, and it's February 2014. You'll be selling that wheat in September of 2014, and right now things are looking pretty decent for your budget, based on what you predict the price of wheat to be at that time. But you're worried, because weather is notoriously unpredictable, and maybe we're going to have a really good year for wheat, with tons of wheat grown all around the world due to amazing weather. It's important to note that this would be *bad* for you, because the price of wheat would go down.
To calm your fears, you want to lock in a specific price. To do this, you sell what is called a "forward contract" that specifies that you will deliver a certain amount of wheat to somebody in September 2014 for a certain price. This way you do not have to worry about the price going up and down between now and then, and can concentrate on your farming.
Note that this works the other way around too; some people need to buy wheat on a regular basis, such as General Mills who uses it to make cereal and stuff. For those people, the danger they are protecting against is the price going *up*.
Now, a forward contract had to be negotiated between a specific buyer and a specific seller, which is kind of a pain in the ass; the farmer doesn't want to go and find a new cereal company to sell to every time he has more wheat, right? So instead we start up a market where *standardized* versions of these contracts can be traded. The standardized contracts are called "futures contracts" and financial types buy and sell them to try to make money. These financial people are "making a market" so that the farmers and cereal-makers don't have to worry about connecting up with each other individually. | [
"A commodities exchange is an exchange, or market, where various commodities are traded. Most commodity markets around the world trade in agricultural products and other raw materials (like wheat, barley, sugar, maize, cotton, cocoa, coffee, milk products, pork bellies, oil, and metals). Trading includes and variou... |
Did Roman gladiators really promote products from the arena? | I'm not aware of any reference in any ancient source to this sort of thing, although I won't rule it out completely. But let's have a look at where the Wikipedia article on the film Gladiator, which is the linked source to the TIL post, gets its information. Ah yes, that reliable historical source, [IGN](_URL_0_):
> There's another historical reference that didn't make the transition from the written word to the big screen, and I can see why. In the script, Maximus did a product endorsement for Olive Oil in the ancient Roman City and had his name plastered on billboards across Italy, but this might not be as far off as you may think. Today, in our sophisticated society that has seemingly evolved so far, we find ourselves surrounded by famous people pushing products, and this is actually how it all began. Although now we find ourselves listening to Michael Jordan telling us what shoes to buy and Grant Hill suggesting what we drink, it's the same principle, and it all started way back when.
This doesn't actually say anything at all. No ancient source is mentioned, it just insists "this is actually how it all began." The idea that a gladiator would promote olive oil seems very dubious to me, because olive oil was such a staple in the classical Mediterranean. It was used for food, medicine, bathing, and lighting, and it has therefore been estimated that each inhabitant of Rome would get through at least 20 litres of the stuff per year, probably more. In the Severan period, shortly after when the film Gladiator is set, oil was added to the state dole, so that any citizen could now claim it for free. Perhaps the article means that gladiators would promote a specific "brand" of olive oil, but brands didn't exist in the same way as they do today. Amphorae might be stamped with the location from where the oil came, but there's no indication that the producers went out of their way to promote their own produce as better than the rest.
Of course, it's dangerous to argue from silence. Just because there is (apparently) no evidence that gladiators promoted products, this does not prove it didn't happen. But I remain sceptical, largely because commercial advertisement in general doesn't seem to have been much of "a thing" in ancient Rome. | [
"Irrespective of their origin, gladiators offered spectators an example of Rome's martial ethics and, in fighting or dying well, they could inspire admiration and popular acclaim. They were celebrated in high and low art, and their value as entertainers was commemorated in precious and commonplace objects throughou... |
how do instant fog windows work? | Liquid crystals embedded in the glass are activated by electricity. They then turn and scatter light that tries to pass through them. | [
"Fog is created by pumping one of a variety of different glycol or glycol/water mixtures (referred to as fog fluid) into a heat exchanger (essentially a block of metal with a resistance heating element in it) and heating until the fluid vapourises, creating a thick translucent or opaque cloud. Devices specifically ... |
AITA for leading my people to a new land, and then setting myself and my family up as de facto gentry? | 100% YTA. Just thought you could roll up on someone elses land and claim your in charge eh??! What about the will of the people! At the very least you could have given them a tax breaks. | [
"So devastating was this for the ranks formerly identified as being of the landed gentry that \"Burke's Landed Gentry\" began, in the 20th century, to include families historically in this category who had ceased to own their ancestral lands. The focus of those who remained in this class shifted from the lands or e... |
What is the burden of proof to Identify/classify a new species? | To name a new species you need to publish a species description in a scientific journal. This is a type of scientific paper that explains what your new species looks like, where it is found, how it lives, and how it differs from any similar known species. You don't need a PhD, but you do need a body -- known as a type specimen -- which you designate and deposit in a university or museum research collection so that other scientists could go back and reference it. | [
"A name of a new species becomes valid (available in zoological terminology) with the date of publication of its formal scientific description. Once the scientist has performed the necessary research to determine that the discovered organism represents a new species, the scientific results are summarized in a scien... |
what triggers evolution in a species? | There is no real trigger... Evolution is the survival of the individual who is best adapted to surroundings. Let's say a pack of mammoths ends up in the desert. Then the amount of hair determines how well a mammoth regulates its body temperature. The overheating mammoth dies, giving the rest of the mammoths more chance to procreate and pass their amount of hair to the next generation. Basically we always evolve, but random mutations that give an individual benefits or not appear randomly, so there's no guarantee that there will be change.
You could say that change of surroundings triggers evolution to cause change but evolution itself is always there. | [
"As we learn with many species, evolution can be driven by a variety of factors. For some, it is competition of various types, and for others, it is a matter of adapting to the changing climate. We learn in the case of \"E. carletoni\" that a bottleneck event occurred between 18,750 and 7,500 years ago, mainly due ... |
how can the human body still have organs that are useless after so many years of evolution? | Evolution is not meant to be perfect, it is meant to make you survive until you reproduce. If an organ is useless, but not hurting enough humans to threaten the species, there is no point in removing it. | [
"Extensive research is required to determine whether animal organs can replace the physiological functions of human organs. Many issues include size – differences in organ size limit the range of potential recipients of xenotransplants; longevity – The lifespan of most pigs is roughly 15 years, currently it is unkn... |
sometimes i have to enter my debit card pin and sometimes i don’t. why? | You can run a debit card as credit, so you won’t have to enter a pin (but you should have to sign for large purchases).
Some merchants run cards as credit for convenience sake (fast food) | [
"Because the customers have to use a PIN code in the BankAxept system, but not with many other systems, it is also much more frequent that stolen debit cards are abused in card fraud with merchants that only have an agreement with the international payment systems and online.\n",
"Some consumers prefer \"credit\"... |
if one person runs 10 miles at a 7 minute pace and another runs 10 miles at at 10 minute pace, who burns more calories? | There is no way to determine that from the information provided. The person running the 10 minute pace might weigh 250 pounds while the 7 minute pace person weighs 100 pounds. All else being equal the movement of a given weight over a set distance requires more power when done faster, but as you pointed out there is significant expenditure of energy into things other than running.
Assuming the same person the higher heart rate, respiration, and all the other functions associated with aerobic exercise would mean that someone in that state for 10 minutes burns more calories than someone only in it for 7 minutes. But then that same person should burn more energy moving their weight 10 miles over 70 minutes vs 10 miles over 100 minutes. How those factors compare depends on the efficiency of the person's running and aerobic state, something we don't really know.
As a general rule of thumb though the greater exertion on the task itself, meaning the faster paced running, will induce the body to produce more muscle and capacity for exertion which means more energy expended. Even if less calories are burned in the exercise period itself the overall expenditure will be higher due to the maintenance energy of the extra muscle. | [
"The situation becomes slightly more complex when preferred walking speed is introduced. The faster the pace, the more calories burned if weight loss is a goal. Maximum heart rate for exercise (220 minus age), when compared to charts of \"fat burning goals\" support many of the references that give the average of 1... |
how does patient zero get sick? | Few options.
Then can be the person in which there was a mutation that allowed the disease to evade the community's immunity. Or they can be the person who brought the disease from a foreign country, or caught it from an animal. | [
"Patient Zero is a 2018 action horror film directed by Stefan Ruzowitzky and written by Mike Le. The film stars Matt Smith, Natalie Dormer, Stanley Tucci, Agyness Deyn, and Clive Standen. The plot involves a group of survivors who set out to find an antidote for a highly contagious virus that turns the infected int... |
what is the us6506148b2 patent? what does it do exactly? how does it work? | The patent claims that by pulsing the image or an electric field at a specific frequency, it can elicit a certain emotional and/or physical response. The patent covers the use of this technology within a television
There does exist transcranial magnetic stimulation, which more or less can do this, but it is targeted by physical location of the magnetic field within the brain, rather than by frequency. Precise enough stimulation of the right brain regions can make someone move an arm.
But that requires much more precision than random electric fields can produce out of a television set. And the patent claims to be able to do this with pulsing magnetic fields over the skin rather than within specific brain regions.
And remember, just because a patent exists, doesn't mean the product exists.
So here's a fun experiment. Wire up an electric coil to an audio cable, and record a TV. Run a fourier analysis, see if you see any spikes other than 50/60Hz (i.e. AC electricity) & HSYNC & their aliases. Then if you don't, cut out that frequency and try an autocorrelation. If there's a magnetic pulse, it'll show up above the noise then. | [
"The law switched the U.S. rights to a patent from the previous \"first-to-invent\" system to a \"first inventor-to-file\" system for patent applications filed on or after March 16, 2013. The law also expanded the definition of prior art used in determining patentability. Actions and prior art that bar patentabilit... |
what is flops and is it a meaningful way to measure a computer's performance? | FLOPS = Floating Point Operations Per Second
It is a meaningful way to measure performance in CPU intensive operations, like computational fluid dynamics. It's still used some in the super-computing benchmark arena.
It's not a meaningful measure of personal computing performance because most operations in your PC are not complex calculations. Much of the PC's work is moving data around or operating system activities that are short on complex matrix math. | [
"FLOPS and MIPS are units of measure for the numerical computing performance of a computer. Floating-point operations are typically used in fields such as scientific computational research. The unit MIPS measures integer performance of a computer. Examples of integer operation include data movement (A to B) or valu... |
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