Split (2)

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Why does the discovery of this LQG (Large Quasar Group) which is 4 billion light years wide, seem to threaten Einstein's Cosmological Principle?	The CP is that the universe is homogenous in every direction and there's no privileged point. Any extremely large structure would violate that principle because it's clearly different than the rest of the universe On the humongous scale of the unverse, imagine the galaxies spread out like static on a mistuned TV. Pick...	[ "Further support for the reality of the Huge-LQG comes from the work of Hutsemékers \"et al.\" in September 2014. They measured the polarization of quasars in the Huge-LQG and found \"a remarkable correlation\" of the polarization vectors on scales larger than 500 Mpc.\n", "The Huge-LQG was estimated to be about ...
Why are there so many volcanic eruptions recently? Are they somehow connected or is it a coincidence? Or is it just new media coverage?	The current level of activity is normal. On average, there are usually ~20 volcanoes in some stage of erupting at any given time. The recent news worthy eruptions (e.g. Hawaii and the recent one in Guatemala) are not connected. So the short answer it's just the coverage and/or the fact that these two eruptions are happ...	[ "Volcanic activity began less than one million years ago and occurred at between 40 and 30 separate volcanic vents. The field erupted various kinds of lavas of mostly basaltic type with a high content of xenoliths, which often underwent interactions with water and thus caused steam explosions and the formation of p...
Why not use Gorilla-Glass for cutting boards?	Hard surfaces like glass ruin the edge on knives. Cutting boards are wood and plastic to allow better and faster chopping and slicing motions while avoiding bending of the blade edge. Don't use glass (or stone or ceramic or anything hard) cutting boards.	[ "Gorilla Glass is a brand of chemically strengthened glass developed and manufactured by Corning, now in its sixth generation, designed to be thin, light and damage-resistant. Gorilla Glass is unique to Corning, but close equivalents exist, including AGC Inc. Dragontrail and Schott AG Xensation.\n", "Gorilla Glas...
why do rich people have credit cards?	It makes more sense for rich people to have them. They can afford to hit all their payments. Credit cards aren't supposed to be for buying shit you can't afford.	[ "On the other hand, the use of a credit card, whose main purpose is similar to money, allows for the creation of highly detailed records about the card owner. Credit cards are therefore not privacy protecting. The main privacy advantage of money is that its users can remain anonymous. There are however other securi...
how did "cheater boxes" (cable descramblers) allow you to watch premium tv channels for free?	Way back when, television was an analog signal. More accurately, it was a series of analog signals that your 100%-analog color television could use to produce a picture. You have three signals for color (your TV only looked at one if it was black-and-white) and a "timing" signal that indicated when it should start dr...	[ "For customers in non-cabled areas, Virgin Media offered a branded set-top box for the Freeview digital terrestrial television service, called \"Free TV\", until December 2009 when it was discontinued. The set-top box was free to any customer taking the Bundle One subscription package or for an addition fee to othe...
what causes hair to have a terminal length?	And why does my beard stop at a certain length?!	[ "Having some hairs that are shorter than others is not necessarily a sign of breakage. Hair naturally sheds as it reaches the end of its growth cycle, and a new hair grows in its place; the average lifespan is about six years.\n", "In most people, scalp hair growth will halt due to follicle devitalization after r...
If air can both heat things up (friction) and cool them down...	Air/wind doesn't have any special heating/cooling properties. It follows the same laws of heat exchange equilibrium that everything else does: If you put something a room with warmer air, it'll get warmer. If you put something in a room with colder air, it will get cooler. But your car engine has something in common...	[ "At high speeds through the air, the object's kinetic energy is converted to heat through compression and friction. At lower speed, the object will lose heat to the air through which it is passing, if the air is cooler. The combined temperature effect of heat from the air and from passage through it is called the s...
Why don't we use deuterium in hydrogen powered cars? Wouldn't it be safer?	It would be equally safe but much much more expensive.	[ "Hydrogen fuel can provide motive power for liquid-propellant rockets, cars, boats and airplanes, portable fuel cell applications or stationary fuel cell applications, which can power an electric motor. The problems of using hydrogen fuel in cars arise from the fact that hydrogen is difficult to store in either a h...
Why did the Roman Pilum(Javelin) die out?	The javelin was a weapon peculiar to Mediterranean warfare, especially for Latin/Italian, Iberian and Celt-Iberian peoples (Sanz 21). The use of javelins (not always the pilum, later the spiculum and earlier a different type, but javelins are all basically the same in function) remained a mainstay of Roman infantry...	[ "A spiculum is a late Roman spear that replaced the pilum as the infantryman's main throwing javelin around 250 AD. Scholars suppose that it could have resulted from the gradual combination of the pilum and two German spears, the angon and the bebra. As more and more Germans joined the Roman army, their culture and...
Are the ocean floors scattered with bones?	I saw an excellent infographic a while back illustrating a "whale fall"--what happens to a whale's body after it dies. I'll look for it. In the meantime, here's an article that goes more in depth about it: [Whale fall](_URL_1_) edit: My mistake, it wasn't an infographic. It was this [video](_URL_0_). Quite beautiful,...	[ "The deposit in which the bones were found was a silty claystone. This was formed from sediments deposited during what seems to have been a rather cool phase of the Late Cretaceous: sea levels of the Western Interior Seaway at least were apparently very low for Mesozoic standards, though this may also have been due...
why water completely damages a cell phone when submerged.	Electronic circuits are designed to only allow electricity to pass through certain parts at certain times. That's how your phone works. It's a set of boolean functions (1 or 0/true or false). Electricity passes through chip, and it makes a decision such as "and/or". If it's 'and', it sends the signal one way, and i...	[ "The phone has been specified to be dust, splash, and water resistant, however, it has not been certified with an IP Code and OnePlus suggests against submerging the device. Water damage is not covered by the warranty.\n", "Electric shock drownings are most commonly caused by improper electrical connections on bo...
Why didn't the Muslims, Indians, Chinese, etc launch colonial efforts on the scale of the Europeans? Or more specifically, what caused the massive rise in colonial efforts in Europe?	There were many economic factors such as competition. The Ottoman Empire had risen to prominence leading up to period of European colonization. They controlled many of the trade routes to the east, and Europeans would have had to pay to use them. So, while it was obviously an economic risk to send ships out into the un...	[ "With the Ottoman Caliphate in a seemingly constant military conflict with Western Europe at their mutual borders, missionary activity in Western Europe was virtually non-existent until the dramatic changing of the European political map in the 20th century. This along with the decline of the Ottoman Empire in the ...
Why is there only a fixed geostationary orbit?	I like to think about this mathematically: If we require that the satellite is undergoing uniform circular motion, the gravitational force must supply all of the centripetal force: F = GmM/r^2 = mv^2 /r (M is the mass of the Earth, and m is the mass of your satellite) which we can solve to get a relation between r a...	[ "A geostationary orbit is a particular type of geosynchronous orbit, which has an orbital period equal to Earth's rotational period, or one sidereal day (23 hours, 56 minutes, 4 seconds). Thus, the distinction is that, while an object in geosynchronous orbit returns to the same point in the sky at the same time eac...
How do we know what we know about Custer's last stand? Are our sources exclusively native? Custer has a reputation as a reckless general and a political opportunist- how much of this was contemporary, vs after the fact? Should he have seen it coming? What were the battle's lasting repercussions?	This is kind of a Thanksgiving version of an answer since I am not at home, don't have access to my books and am writing purely from memory. Should it happen that I have the time and energy to more adequately address all of your questions at some later date --like maybe tomorrow?-- I will. With regard to whether...	[ "However, Custer's reputation had been damaged. While attempting to restore his military prestige in the U.S. Army, Col. Custer was killed in action at the Battle of the Little Big Horn. Belknap had allowed the sale of superior military weapons to hostile Native Americans at trader posts, while having supplied sold...
the difference between an hmo insurance plan and a ppo insurance plan, or different insurance plans in general, i suppose.	Ok. HMO = Health Maintenance Organization. It's where you have one doctor who oversees your general care: your Primary Care Physician [PCP]. Your PCP is the one you see most often, and who is most familiar with your situation. The PCP determines if you need to see a specialist for lab work or additional servi...	[ "A Unit-Linked Insurance Plan is essentially a combination of insurance and an investment vehicle. A portion of the premium paid by the policyholder is utilized to provide insurance coverage to the policyholder and the remaining portion is invested in equity and debt instruments. The aggregate premiums collected by...
how come when stars explode, they gush their matter out in 2 dimensions?	Doesn't that image [look familiar](_URL_0_)? The spectral matter is chasing the magnetic field.	[ "These interesting objects are born from once-large stars that grew to four to eight times the size of our own sun before exploding in catastrophic supernovae. After such an explosion blows a star's outer layers into space, the core remains—but it no longer produces nuclear fusion. With no outward pressure from fus...
Why did Vladimir I of Kievan Rus embrace Byzantine Orthodoxy rather than Catholicism?	Adding to the question, I just today read ("The Western Heritage since 1300 AP* Edition), that not only were there Catholic and Orthodox representatives plying for religious control of Russia, but there were also Jewish and Muslim representatives too. Was there any reason to choosing one over the other? Were Jews and M...	[ "In 988, Vladimir of Kievan Rus' rejected Slavic religion and he and his subjects were officially baptised into the Eastern Orthodox Church, then the state religion of the Byzantine Empire. According to legend, Vladimir sent delegates to foreign states to determine what was the most convincing religion to be adopte...
how come humans seem to be the only animal that require whiping their ass after shitting?	You might not like the answer. Other animals don't need to wipe because they can reach around and clean themselves with their tongue. They still clean themselves as needed, I'm surprised you haven't seen the dog doing it.	[ "Whips are generally used on animals to provide directional guidance or to encourage movement. Some whips are designed to control animals by imparting discomfort by tapping or pain by a full-force strike that produces pain compliance. Some whips provide guidance by the use of sound, such as cracking of a bullwhip. ...
how are doctors incentivized to be better and compete for careers in the toughest specialties within healthcare systems that are socialized?	Countries with public healthcare still have private practices which you can pay money to see. There's a basic service provided by the government, but nobody is stopping patients from purchasing more extensive coverage on top of it. You also have to keep in mind that hospitals are still competing with each other, so th...	[ "A survey published in 2009 found that PEM physicians report higher career satisfaction than doctors in all other specialties. Per doximity, pediatric emergency physicians in the U.S. make an average of $273,683 yearly. They also work fewer hours than do other subspecialists.\n", "Pre-Health Sciences are the unde...
How much of ancient history are we missing?	Well, "history" is the study of text, but generally that means that it only goes back as far as there has been written word (and myths and oral histories etc). In Western Eurasia, this goes back to the Sumerians in about the fourth millennium, although one could argue that you still can't really do "history" for some t...	[ "BULLET::::- Indraprastha, the legendary Ancient City is believed to have been established 5000 years ago (c. 2800 BC), as per the ancient Indian text- the Mahabharata. Though very much a part of India's very Ancient history, it lacks any tangible evidence to say without doubt that it existed. Archaeological eviden...
how in boxing a person can get cut when punched by someone wearing gloves?	Friction. Even with gloves on, often times glancing blows still carry enough force to cause enough glove-to-skin friction to split the skin open. This is why you see boxers and fighters put Vaseline on their cheeks and eyebrows.	[ "Hand and wrist wraps are used to compress (and keep compressed when hitting) the bones and tissues in the hand. The claim is that such compression allows boxers to hit with greater force than if they did not use them. Boxers claim they feel less pain when hitting so their opponent may feel more pain. \n", "In ge...
why are some people coordinated and some people not? what in your brain determines how coordinated you are?	*Hand-eye coordination* is quite complex, involving several regions of your brain dedicated to processing visual information, motor control, proprioception, eye movement, et cetera. Generally speaking and without getting into details of human neuroanatomy, this kind of coordination requires your *brain*...	[ "Coordination refers to the extent of necessity in explicit revealed planning and coordinating efforts during teamwork. When a group possesses a strong transactive memory system, the need for explicit coordination efforts reduces since teammates are aware of other teammates strengths and weaknesses, can anticipate ...
how is america not totally collapsing because of debt and the dollar bill losing value?	The US is in such a better financial position than it was just 7-8 years ago. No one's talking about the banks and financial system collapsing this time. Almost all countries have debt. Debt isn't a problem unless other countries stop believing you can pay it back eventually. The dollar is neither particularl...	[ "The U.S. government continued to run large deficits post-crisis, with the national debt rising from $10.0 trillion as of September 2008 to $16.1 trillion by September 2012. The debt increases were $1.89 trillion in fiscal year 2009, $1.65 trillion in 2010, $1.23 trillion in 2011, and $1.26 trillion in 2012.\n", ...
At the time, did people think there would be a WW2?	Marshal Ferdinand Foch, the man who accepted the german armistice famously stated in 1919, ["This is not a peace. It is an armistice for twenty years".](_URL_0_) He was correct, WWII began 20 years and 64 days later. He was not the only one who shared that sentiment. Winston Churchill avidly spoke about rearmament duri...	[ "Prior to the beginning of the Second World War, the First World War (1914–1918) was believed to have been \"the war to end all wars,\" as it was popularly believed that never again could there possibly be a global conflict of such magnitude. During the interwar period, WWI was typically referred to simply as \"The...
how does the government keep increasing the debt ceiling? are they simply pushing the debt onto the future generation?	The debt ceiling is an artificial limit on debt. It has no effect on actual interest rates or the borrowing power of the US. It is simply a red tape tool used to cause debate about spending every few months. Because it was created by congress, they can also raise it. This is like you saying, I'm only going to eat 6 mor...	[ "A vote to increase the debt ceiling has usually been (since the 1950s) a legal budgetary formality between the President and Congress. The debt ceiling has not historically been a political issue that would make the elected government fail to pass a yearly budget. Reports to Congress (from the OMB and other source...
Why must an electric charge be moving to experience a force inside a magnetic field?	> But what if the external electron is stationary? In that case, wouldn't the electrons inside the conductor undergo length contraction because they have a velocity relative to our external electron, resulting in a net negative charge? Shouldn't that also exert a force? A steady current in a wire implies that the wir...	[ "Electrical charges interact via a field. That field is called electric field.If the charge doesn't move. If the charge moves, thus realizing an electric current, especially in an electrically neutral conductor, that field is called magnetic.\n", "A charged particle moving in a -field experiences a \"sideways\" f...
why jeremy corbyn is being described as a 'threat to national security'	If you say something is a threat to nation security or something similar you will automatically mobilize a huge segment of conservative votership against someone. It's nothing more than a cheap political move, but it will probably work.	[ "He also claims that insecure messaging puts national security at risk. He claims that since the White House staffers must bypass government servers, their email is traveling across the Internet without necessary security. He cites numerous national security risk scenarios that could occur due to possible intercept...
Do "non-water rainbows" exist and (if yes) what do they look like?	The main difference between different liquids boils down to their indices of refraction and their dispersion. Changes in the index of refraction would alter the size of the rainbow arc, while changes in their dispersion would change how wide the actual rainbow band is. If the dispersion is negative, it would also flip ...	[ "The rainbow, a natural phenomenon noted for its beauty and mystical appearance, has been a favorite component of mythology throughout history. Rainbows are part of the myths of many cultures around the world. The Norse saw it as Bifrost; Abrahamic traditions see it as a covenant with God not to destroy the world b...
Would it be possible to use MagLev technology for faster/ cheaper Space Shuttle launches?	This is definitely possible; a more practical arrangement would be a straight track running through a tunnel angled through a mountain range pointed along your desired orbit. You probably wouldn't want to use magnetic levitation exactly either, rather a sled propelled through electromagnetic propulsion. There are a va...	[ "NASA has been developing a launch aid using a magnetic levitation system to propel a spaceship. Proponents of maglev launch aid posit that it saves on design and launching costs, while providing a safer launching method.\n", "James R. Powell, former co-inventor of superconducting maglev in the 1960s, has since 2...
When a new language is discovered, how do people start deciphering it?	Ooh! I can answer this one. Sort of. I studied linguistics at university, and Field Methods is one of the major aspects. So, while I can't talk about the historical aspect, I can talk about the modern approach. I can't imagine there's much that has changed there aside from the rigor of the method (you'll see what I m...	[ "There are some linguists who question the very possibility of tracing language elements so far back into the past. Campbell notes that given the time elapsed since the origin of human language, every word from that time would have been replaced or changed beyond recognition in all languages today. Campbell harshly...
- how do we perceive color?	if you are british you can watch this _URL_0_ its an episode of horizon that explores how people see colour. in recent research there's evidence that not everybody sees it the same way. for example in modern society we see primary and secondary colours as being very distinct. but a certain african tribe find it diffi...	[ "Color vision is how we perceive the objective color, which people, animals and machines are able to distinguish objects based on the different wavelengths of light reflected, transmitted, or emitted by the object. In humans, light is detected by the eye using two types of photoreceptors, cones and rods, which send...
Is there a trade off that makes it hard for a virus to be both very contagious and very deadly?	Yeah, viruses that are overly virulent kill their hosts before they are able to transmit the virus to new hosts, so more deadly viral lineages tend to burn out before being widely transmitted. So there's an evolutionary trade off between high virulence and a strain's ability to maintain itself in a population.	[ "Dr. Anthony S. Fauci of the National Institutes of Health in Bethesda, Maryland, stated that as of now MERS-CoV \"does not spread in a sustained person to person way at all.\" Dr. Fauci stated that there is potential danger in that it is possible for the virus to mutate into a strain that does transmit from person...
(tennis elbow) why does applying pressure to the mid-arm, such as using a compression sleeve, greatly reduce or eliminate pain from tennis elbow?	The compression bands are meant to be worn about an inch or two down from where the tendon attaches to the bone. This helps to take the pressure off the tendon and allow it to heal. Basically the bands make our body think that the tendon actually attaches at the band, rather than at the bone. This allows the tendon to ...	[ "Tennis elbow, also known as lateral epicondylitis, is a condition in which the outer part of the elbow becomes painful and tender. The pain may also extend into the back of the forearm and grip strength may be weak. Onset of symptoms is generally gradual. Golfer's elbow is a similar condition that affects the insi...
how is amd still in business?	> they seem to consistently post losses, in both revenue and market share. That's not enough information. Is that in only one market sector? AMD gave up on the PC market years ago, and that only makes up a small percent of their entire revenue stream. They make semi-conductors, and that's more than just processors, ...	[ "By February 2015, roughly 40 percent of AMD's sales came from non-PC markets, such as video game consoles and embedded devices. When Su joined AMD in 2012, about 10 percent of sales came from non-PC products. In May 2015, Su and other AMD executives presented a long-term strategy for the company to focus on develo...
Can a planet have a core made of diamond?	Not a core, but a planet with a higher carbon/oxygen ratio than Earth might end up with a mantle composed of diamond and silica carbide. However, these materials are poorer insulators than the silicate-dominated mantle we have, so such a planet would cool fairly rapidly in its interior and lack surface tectonics and vo...	[ "Such a planet would probably have an iron- or steel-rich core like the known terrestrial planets. Surrounding that would be molten silicon carbide and titanium carbide. Above that, a layer of carbon in the form of graphite, possibly with a kilometers-thick substratum of diamond if there is sufficient pressure. Dur...
Is it possible for a conductive room temperature gas to exist?	Generally no, gases don't have free electrons. If you ionized it, it would be a plasma (which does conduct), and if you're asking if there is cold plasma, [there is](_URL_0_) (they're in fluorescent lights).	[ "Below the operating temperature, the liquid is too cold and cannot vaporize into a gas. Above the operating temperature, all the liquid has turned to gas, and the environmental temperature is too high for any of the gas to condense. In other words, whether too high or too low, thermal conduction is still possible ...
how does overall wealth actually increase?	When we convert raw materials into other resources, the value increases. Raw steel and rocks isn’t that useful, but build a building and you can house people/do commercial activities. Wood isn’t useful, but you can print knowledge on paper and books are more valuable than raw wood. This concept extends to ideas, not ...	[ "Wealth concentration is the process by which, under certain conditions, newly created wealth concentrates in the possession of already-wealthy individuals or entities. Accordingly, those who already hold wealth have the means to invest in new sources of creating wealth or to otherwise leverage the accumulation of ...
Is our solar system falling through space?	> Are we "falling?" In the sense that orbiting celestial bodies are in an [inertial frame of reference](_URL_0_), and falling while on earth also places you in an inertial reference frame, then yes, stars and planets are "falling". But don't confuse that with there being some sort of universal "down" direction that ...	[ "It is a common misconception that this collision will disrupt the orbits of the planets in the Solar System. Although it is true that the gravity of passing stars can detach planets into interstellar space, distances between stars are so great that the likelihood of the Milky Way–Andromeda collision causing such d...
why a bunch of people have birthdays the same day?	You expect to see lots of pairs (we'd need more precise data to determine whether your group of friends shows more than the expected number, however). Although this is counterintuitive at first glance, it's actually fairly obvious if you look at it the right way. The point is that although the chance of any two peop...	[ "According to a public database of births, birthdays in the United States are quite evenly distributed for the most part, but there tend to be more births in September and October. This may be because there is a holiday season nine months before (the human gestation period is about nine months), or because the long...
why do we feel the need to play with our phone or read something while pooping?	It's boring. We need something to keep our minds occupied. Reader's Digest was the original smartphone for that.	[ "For students who know how to read, but need extra encouragement, giving a book talk is a way to inspire reading. It is an especially effective tool with reluctant readers who need a hook before they will invest the energy into reading a book. Reading motivation for children can be enhanced when it is read with son...
why does stroking animals relax/calm us down?	i covered this topic in a class in university way back in the caveman days they would sit around the fire with their half wild dogs stroking their fur elicited the guard guard guard instinct in the animal thats the theory anyways so basically the theory is we were able to relax knowing we were protected	[ "Humans also often seek to mimic animals' communicative signals in order to interact with them. For example, cats have a mild affiliative response of slowly closing their eyes; humans often mimic this signal towards a pet cat to establish a tolerant relationship. Stroking, petting and rubbing pet animals are all ac...
What affects continental drift?	Here's a reconstruction of the last ~250 million years, which basically shows the break up of Pangea. The thing to remember is that Pangea is only the most recent supercontinent; there have been at least 6 or 7 over Earth's 4.5 billion year history. _URL_0_ The driving force, very simply, is gravity. Thermal buoyancy ...	[ "Continental drift is the theory which emerged in the early 20th Century that the Earth's continents have moved over geologic time relative to each other, thus appearing to have \"drifted\" across the ocean bed. The idea of continental drift was subsumed by the theory of plate tectonics in the mid-20th century. Pla...
why we have the right to bear arms (guns), but not swords?	If the Congress of the United States tried to pass a law unreasonably restricting your right to keep and bear a sword, that law would be challenged on the same grounds as a law unreasonably restricting your right to keep and bear a gun. "Arms" means arms. It doesn't mean firearms specifically.	[ "The people's right to have their own arms for their defense is described in the philosophical and political writings of Aristotle, Cicero, John Locke, Machiavelli, the English Whigs and others. Though possessing arms appears to be distinct from \"bearing\" them, the possession of arms is recognized as necessary fo...
What are the greatest "missing" objects that are probably still in existence? (stolen etc.)	Actually, there are a lot of papyri and archeological pieces from the ancient Egypt which have never been studied by archeologists and egyptologists. These numerous missing objects are actually in the hands of collectionners. This is the result of the state of egyptology in the 18th and 19th centuries : Egyptology as...	[ "The museum announced in July 2006, that 221 minor items, including jewelry, Orthodox icons, silverware and richly enameled objects, had been stolen. The value of the stolen items was estimated to be approximately $543,000 but by the end of 2006 several of the stolen items were recovered.\n", "Altogether, thirtee...
Why can't I remember a smell or taste the same way I can an image or a sound?	Perfumer here. With training any person would be able to replicate smells inside their heads as well as any visual or auditory input. The main problem is cultural. Our western society does not value the sense of smell as highly as other senses: children are not taught to notice odors, our olfactory "vocabulary" is real...	[ "The only thing that is currently agreed upon is that the brain does actually group different information, and many associations are instantly created when viewing or remembering images, numbers or sounds.\n", "An odor can cue recall of a distant memory. Most memories that pertain to odor come from the first deca...
Anyone know of any mafia families who had their sons serve in World War II? Any post-WWII crime bosses who were veterans?	One of my favorite fiction books is The Fortunate Pilgrim by Mario Puzo, and it's about an Italian-American family living in New York. One of the sons of the family is involved with organized crime (the Italian mafia, if you will) and another is conscripted to go fight WWII. The dynamic between the brothers is great....	[ "His life parallels that of his close friend Paolo Borsellino. They both spent their early years in the same neighbourhood in Palermo. Though many of their childhood friends grew up in the Mafia background, both men fought on the other side of the war as prosecuting magistrates. They were both killed in 1992, a few...
how to differentiate whether a person is chinese, japanese, korean, etc. (honest question - not meant to seem racist)	Sometimes you can tell by their surnames. Common Korean names are Kim, Park, Cho, or Han. Very simple. You can usually recognize a Japanese name, like Takahashi, Nakamura, Hayashi, Yamamoto, etc. - very different from Korean or Chinese names. Japanese names never start with V, X, or Z, but Chinese names may start with ...	[ "The concept of as represented in Japanese makes no distinction between racial, ethnic, and national identities. Where the census of the United Kingdom, for example, separates \"ethnic or racial background\" from nationality, the Japanese Census and Statistics Bureau do not distinguish between the two.\n", "Chine...
why do we have phobias that weren't a result of early experiences?	A fear of clowns deals with something known as the "uncanny valley". It applies to objects that are close enough to humans to be recognized as such, but they aren't quite "right". Features are drawn to be highly exaggerated. Your brain doesn't know how to react. "It's like me... But it's not. It might attack." It...	[ "Another experience that doctors believe leads individuals to develop this phobia is children being abandoned, usually by their parents, when they are very young. This first causes childhood trauma that then persists to affect them as they grow up. This turns into autophobia because they are now afraid that all of ...
through what mechanism is a ventilator an effective treatment for respiratory illness?	The patient can still take extra breaths when the body is signaling it needs more oxygen, but a ventilator takes away the work of breathing (the energy required to move the diaphragm again and again). A patients diaphragm may not be able to keep up with inspiratory demands with the rest of the body needing energy for o...	[ "A medical ventilator (or simply ventilator in context) is a machine designed to provide mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently.\n", "Ventilators come in many different styles and m...
Why did the Great Migration in US history start in the 1910s instead of earlier like after the Civil War (1865) or the end of Reconstruction (1877)?	Essentially you've hit the nail on the head with your last sentence > a perceived lack of opportunity in the North While the First Great Migration (1910-1930) was largely caused by the brutality of Jim Crow Laws and Lynchings, another reason were the increased job opportunities in the North, which largely didn't exi...	[ "The decreases in population from 1910–1920, and from 1940–1960, were chiefly caused by different phases of the Great Migration, as African Americans left segregation and oppression of the South to seek better opportunities in the North, during the first phase, and in the West, especially California's defense indus...
The ocean level stands for 0 high. If the ocean level rises, will the understanding of 0 high change too?	The notion of 'sea level' isn't actually the current sea level because that changes from year to year and more profoundly from place to place. Weather, moon, the geography of the water body in the area, and climate change, are just a few of the things that change 'actual' sea level (this is all from [Wikipedia](_URL_0_...	[ "The \"global mean sea level is projected rise (relative to 1986-2005) by 0.26 to 0.77m by 2100 for 1.5°C global warming\" and about 0.1m more for 2°C. A difference of 0.1m may correspond to 10 million more or fewer people exposed to related risks.\n", "Mean sea level (MSL) (often shortened to sea level) is an av...
why does bacteria grow faster at certain temperature?	All bacteria have certain temperatures that their enzymes, or proteins in their bodies which process nutrients and other things perform at the maximum rate. As the environment temperature increases, enzyme action increases until it reaches a high enough temperature that enzymes denature, meaning that their substrate ar...	[ "External conditions such as acidity and temperature affect the growth rates of \"Lactobacillus sanfrancisco\". One study found that of temperature of 33 °C (91 °F) leads to maximum growth rates, whereas temperatures over 41 °C (105 °F) completely inhibit the bacteria growth. Ideal and maximum growth temperatures o...
if double jeopardy exists, why can a judge overturn a sentencing and retry someone?	He was already found guilty, the issue here is that the sentence for the guilt was out of line considering the sentencing guidelines. Double Jeopardy protects from being tried again for the same crime (decision of guilt or not), not protection from an improper trial (hung jury, mistrial, etc).	[ "The Court also explained why the Double Jeopardy Clause permits a second prosecution following reversal for trial error—such as flawed jury instructions, evidentiary rulings, or prosecutorial misconduct—but not for evidentiary insufficiency. Because trial errors \"impl[y] nothing with respect to the guilt or innoc...
Quick high school chemistry question	They're both technically correct, but your dad is correcter.	[ "After the on-line questions, students will take a test about what they have learned while solving the on-line questions. First grade students in high school take this test. The questions are based on basic chemistry. The test can determine how much the students understand basic chemistry. 80 well-ranked students c...
why do waterproof materials (tents and shower curtains) let water through when something touches it?	They're not really waterproof, is the simple answer. They're mostly waterproof, and rely on angles to shed and wick the water away faster than it would drip out the other side. This means you can make a relatively light and inexpensive material that still allows for airflow. As to why your finger makes it come thro...	[ "Waterproof/breathable fabrics resist liquid water passing through, but allow water vapour to pass through. Their ability to block out rain and snow while allowing vapour from sweat to evaporate leads to their use in rainwear, waterproof outdoor sports clothing, tents, and other applications.\n", "Tent fabric may...
how is space debris tracked?	The [US Space Surveillance Network](_URL_0_) includes both ground-based sensors and satellites that do the tracking.	[ "Measurements of near-Earth orbital debris are accomplished by conducting ground-based and space-based observations of the orbital debris environment. Data is acquired using ground-based radars and optical telescopes , space-based telescopes, and analysis of spacecraft surfaces returned from space. Some important d...
how can a founder of a company, like papa john, be forced to step down from ceo	Papa John's is a publicly traded company. This means that individuals can buy portions of the company called "shares" and the company can use that money to invest and grow. John Schnatter kept 25% of the company for himself when they went public, but the other 75% was sold in order to grow the brand. The sharehold...	[ "In the three years subsequent to the firm being founded, Wasserman concluded 50% of founder CEOs step down. The following year, another 10% step down and by the time the firm has an initial public offering less than 25% of founders still hold the CEO position. This being said, the decision to step down is not alwa...
How do sunburns go away?	A sunburn isn't the same as a tan. Tans are caused by the production of melanin in the skin as a response to sun exposure. Sunburns are the layers of your skin literally being burned by sunlight, and the redness is caused by inflammation, not pigment. The redness goes away as healing occurs.	[ "Sunburn is caused by UV radiation, either from the sun or from artificial sources, such as tanning lamps, welding arcs, or ultraviolet germicidal irradiation. It is a reaction of the body to direct DNA damage from UVB light. This damage is mainly the formation of a thymine dimer. The damage is recognized by the bo...
why is rent control a bad thing?	One of the main reason capitalism works is that prices somewhat accurately reflect supply and demand. Rent control takes away this information. As a result, there isn't the same incentive to create new developments. Less new development means less supply, which would increase prices, but they're kept artificially low w...	[ "Rent controls are often enacted due to public pressure and complaints regarding the cost of living. Proponents of rent controls argue that rent controls combat inflation, stabilize the economic characteristics of a city's population, prevent rent gouging, and improve the quality of housing. Capitalist economists h...
How does a computer graph a function?	It plots individual points. "Insane" is an exaggeration. Think about this, say you had a super HD 4K monitor and had the graph going across the entire screen. If the software were to individually compute every pixel it displays... it would only have to compute about 4000 points, one for every x value, which is not hard...	[ "In the modern foundations of mathematics, and, typically, in set theory, a function is actually equal to its graph. However, it is often useful to see functions as mappings, which consist not only of the relation between input and output, but also which set is the domain, and which set is the codomain. For example...
Why did the Constitution specify March 4 (the date) for the start of the new president's term? Why did FDR specify January 20 (the date) as the new date in the 20th amendment?	To answer the first part of your question: The Constitution did not specify March 4, or any other date, as the beginning of the new President's term. It stated only that the length of the President's term was four years. And, while the Constitution gave Congress the power to set the date for the selection of Ele...	[ "Efforts to change these dates through a constitutional amendment began in the late 1920s. In March 1932, Congress approved a constitutional amendment moving the beginning and ending of the terms of the president and vice president from March 4 to January 20, and of members of Congress from March 4 to January 3. Th...
what happened at the nevada democratic convention last night?	There are many videos of what is apparently misconduct in the voting process aimed at benefitting Hillary Clinton and suppressing the supporters of Bernie Sanders.	[ "The Nevada caucuses are an electoral event in which citizens of the U.S. state of Nevada meet in precinct caucuses to elect delegates to the corresponding county conventions. There are 17 counties in Nevada and so there are 17 conventions. The county conventions then select delegates to Nevada's State Convention, ...
what makes even "healthy" or "normal" people sad from time-to-time for no reason at all (it seems like)?	Every now and then I remember how pointless and insignificant everyone's lives are.	[ "Research has found that the onset of SAD typically occurs between the ages of 20–30 years, but most affected people do not seek medical help. This could be due to the stigma of mental health issues. Many are afraid to state they are suffering and would rather hide it. As a society, we should push forward towards g...
How did showering to clean one's body become a thing?	William Feetham patented a chain-release shower in 1767. In the late 1800s communal showers took hold by French military, under the direction of physician François Merry Delabost who had first tried them out on prisoners for reasons of economics and hygiene. In modern times showers did not start to become common until...	[ "Showering is mostly part of a daily routine primarily to promote cleanliness and prevent odor, disease and infection. Advances in science and medicine in the 19th century began to realize the benefit of regular bathing to an individual's health. As a result, most modern cultures encourage a daily personal hygiene ...
Could DNA fossilize?	Unfortunately probably not. A relatively recent study pegged the half life of DNA at around 500 years depending on the environmental surroundings. So every 500 years roughly half of the remaining bonds in the DNA molecule will be broken. After 2000 years, you would only expect 1/16 of the bonds to be remaining. And it'...	[ "Researchers in 2016 measured chloroplast DNA in marine sediment cores, and found diatom DNA dating back to 1.4 million years. This DNA had a half-life significantly longer than previous research, of up to 15,000 years. Kirkpatrick's team also found that DNA only decayed along a half-life rate until about 100 thous...
Would a single candle in an otherwise unlit circus Hall of Mirrors provide the same lighting effect as an equivalent number of real candles (equivalent to the number of reflections) in a normal room?	Think of it this way. For every mirror there is an area NOT lit because light headed for that area was redirected by the mirror, at a loss because the mirror is not 100% efficient. That's where the seemingly "extra" light comes from.	[ "The illumination problem is a resolved mathematical problem attributed to Ernst Straus in the 1950s. Straus asked if a room with mirrored walls can always be illuminated by a single point light source, allowing for repeated reflection of light off the mirrored walls. Alternatively, the question can be stated as as...
the weekend	From a Euro-American perspective, the Sabbath has been around since Biblical times, so the idea of having one day per week to take a break is ancient. I believe that current 5-day work week started around the later Industrial revolution, when more people began paying attention to things like worker welfare (no more c...	[ "The weekend is that period of the week set aside by custom or law for rest from labor. In many countries it is Saturday and Sunday and often includes Friday night. This five-day workweek arose in America when labor unions attempted to accommodate Jewish Sabbath, beginning at a New England cotton mill and also inst...
Hitler glorified blonde hair and blue eyes, yet he himself didn't look stereotypically "Aryan". Did he consider himself and the other Austrians to be "lower quality Aryans" and the Scandinavians "higher quality Aryans"? I.e did he consider himself "pure"?	Hitler discussed this in Mein Kampf. He promoted the idea of five sub-races of the Aryan people. Dinaric, Alpine, mediterranean, Nordic, and Eastern Baltic. The best kind of Aryan is, you probably guessed it, are the predominantly blue eyed and fair headed Nordics. This was actually very popular, Nordicism I mean, ...	[ "The Nazis considered the purest Aryans to be those that belonged to the \"Nordic race\" physical ideal, known as the \"master race\" during Nazi Germany. Although the physical ideal of the Nazi racial theorists was typically the tall, fair-haired and light-eyed Nordic individual, such theorists accepted the fact t...
what's the purpose for the mid season finale pretty much all shows have now?	Lets everybody enjoy their holidays without watching TV and having to keep up while with family and gives more time to film and edit episodes	[ "The finale was written by co-creator/executive producer Damon Lindelof and executive producer Carlton Cuse, and directed by executive producer Jack Bender. Unlike the previous season finales, which were two hours long with advertisements, the series finale was expanded by half an hour, running two and a half hours...
why are animals and plants so distinct, e.g why aren't there any plants that can walk or animals that do photosynthesis?	There are animals like a sponge that you would likely mistake for a plant if you didn't know better, and plants that can move and eat "meat" like a venus fly trap. I know that plants and animals are different in that plants have cell walls and animals have cell membranes, and given how far back on the tree of life we ...	[ "Plants are often the dominant physical and structural component of habitats where they occur. Many of the Earth's biomes are named for the type of vegetation because plants are the dominant organisms in those biomes, such as grasslands, taiga and tropical rainforest.\n", "Plants, like all known organisms, use DN...
what would actually happen if we built a tunnel from one side of the earth to the other and then proceeded to drop something through it?	People that claim it would oscillate back and forth are wrong. It's a nice thought, but it's a misinterpretation of the laws of nature. That would happen if the gravity of earth was created by a small point at the centre of the earth, and that the object "falling" could pass through that point. First of all, lets tak...	[ "Because the tunnel was not straight, it was not possible to see if someone had entered the tunnel from the other end. To overcome this, a byelaw was introduced which stated that whoever reached the centre first should continue, whilst the other boat would have to turn back.\n", "The tunnellers developed counter ...
what is the election everyone in america is talking about and what could it change in the american political system (i'm not american)	Every two years, the entire House of Representatives and 1/3 of the Senate are up for election. This gives the possibility to flip the majority party in both chambers of the federal legislature, making it more difficult to pass legislation preferred by the Republican party. (But not enough to give a veto-proof Democr...	[ "America Votes is a 501(c)4 organization that aims \"to coordinate and promote progressive issues.\" America Votes leads national and state-based coalitions to advance progressive policies and increase voter turnout for Democratic Party candidates.\n", "Americans Elect was a political organization in the United S...
why is the nanking massacre so controversial among the chinese and japanese? which is correct?	considering there are living witnesses to some of the atrocities, it's hard to deny atrocities happened. the Japanese story says there was no high level orders. and whatever stories of individual soldiers committing actions must have been fabrications because honorable soldiers always follow orders. just like flat ...	[ "Nanking Massacre denial is the denial that Imperial Japanese forces murdered hundreds of thousands of Chinese soldiers and civilians in the city of Nanjing during the Second Sino-Japanese War, a highly controversial episode in Sino-Japanese relations. Some historians accept the findings of the Tokyo tribunal with ...
why auto insurance companies allowed to discriminate?	It's not a denial of service or something like preferential treatment for a certain race, gender, etc. Actuarial science is just that: a science. Insurance is a business, and the different variables that determine how much someone pays for their insurance are based on past and present statistics of behavior. The price ...	[ "Proponents of no-fault insurance argue that automobile collisions are inevitable and that at-fault drivers are not necessarily higher risk and should not necessarily be punished; moreover, they note that the presence of liability insurance insulates reckless or negligent drivers from financial disincentives of lit...
Why was the 5.56mm round chosen as the NATO standard?	in 1977 NATO agreed to adopt a 2nd round in addition to the 7.62x51mm round, specifically the SS109 steel tipped round which was designed to pierce a soviet style steel helmet at 600 meters. Jane's Infantry Weapons 1986–1987, pg. 362 The Small Arms Review vol.10, no.2 November 2006. It's 4am and I haven't looked int...	[ "Therefore, in March 1970, the U.S. recommended that all NATO forces adopt the 5.56×45mm cartridge. This shift represented a change in the philosophy of the military's long-held position about caliber size. By the middle of the 1970s, other armies were looking at assault rifle type weapons. A NATO standardization e...
why is the death of one lion such a huge story but the extinction of rhinos in the wild barely makes the news?	Because people want something to be upset about and this is the newest thing. Two weeks ago, no one ever even knew about this goddamn lion. The news said we should be mad, so everyone got pissed. Outrage gives people a feeling of purpose.	[ "The zoo witnessed a series of animal deaths in 2004 and 2005. In August 2004, a Lion-tailed macaque was found mysteriously dead. An emu and a tiger were also reported to have died mysteriously. On 4 September 2004, an elephant died, reportedly of acute hemorrhagic enteritis and respiratory distress. It was reporte...
Looking for some career guidance. (post-undergrad)	Your question is certainly welcome here but you might want to try posting it to /r/AskAcademia too – they're good with career advice.	[ "The Career Days is a project organized by the international organization called AIESEC. Its main aim is to inform students about the actual offers on the labor market. Students are encouraged to come into direct contact with potential employers of various companies and exchange information with them. The project c...
how come i can see a vein bulging out of my left bicep, but not my right, even though i work out each arm equally?	Your body is not an anatomical mirror. Your left side does not mirror your rigt side. Same as your left index finger is not identical to your right index finger. Thus your veins runs 'differently' in your body, meaning that some are close to the skin and some are not. Another contributing factor might also be that you ...	[ "\"The other runs upward by the right veins in the lungs and divides into branches for the heart and the right arm. The remaining part of it rises across the clavicle to the right side of the neck, and is superficial so as to be seen; near the ear it is concealed, and there it divides; its thickest, largest, and mo...
milk expiration dates	If you say that it's literally same exact milk (same brand, same type, same size, etc) then its probably different stocks. Lets say Whole Foods bought milk 2 weeks ago and Safeway bought theirs 2 days ago. So WF's milk is older, and thus expires sooner. However if you mean that brands are different, but product is ess...	[ "The shelf life of canned evaporated milk varies according to both its added content and its proportion of fat. For the regular unsweetened product a life of fifteen months can be expected before any noticeable destabilization occurs.\n", "Milk preserved by the UHT process does not need to be refrigerated before ...
Is it possible to make an anti-matter atomic bomb?	Yes although we don't have anything close to the technology to make that. If exploded in a vacuum it would look the same as a regular nuclear bomb, if it was in contact with regular matter than there'd be an intense burst of gamma radiation as it annihilates with regular matter.	[ "Antimatter production and containment are currently impenetrable barriers (due to current technological limitations) to the creation of antimatter weapons. Quantities measured in grams will be required to achieve a destructive effect comparable with conventional nuclear weapons.\n", "Antimatter has been consider...
I've noticed on a lot of milk crates they say something along the lines of "using this for anything other than milk is punishable by law" was stealing milk crates ever such a big problem that they had to make a law to address it or was this just a precaution?	Yes, that is the case. During the 1970s and 80s these plastic crates were regularly pilfered because of their solid construction and light weight. Today manufacturers have copied these designs and they're sold in stores as consumer goods. Some states have similar laws for shopping carts, possession is illegal.	[ "It was held that (1) the ban on plastic nonreturnable milk containers was rationally related to the achievement of legitimate state purposes and thus did not violate the equal protection or due process clauses of the Fourteenth Amendment, since the state legislature could rationally have decided that its ban on pl...
how do the ads next to porn videos know where i am?	Kids these days are exposed to porn at a far too early age.	[ "The rest of the video alternates between the pitching of advertising ideas and the concepts being shown in real time. The advertisement within the video opens with a woman (Lauren Francesca) in a two-piece running outfit jogging down a street, who is later joined by a second woman (Nicola Fiori) also jogging and s...
how come americans have large portion sizes and relatively cheap prices for their food?	When you go to a restaurant, you pay for the service first, then for the actual food. As a rule of thumb, the ingredients usually make up only 1/4 to 1/3 of the costs. Additionally, the work of preparing a dish twice as large usually isn't twice as much for the chef. So it comes down to the customer's expectations. Am...	[ "Portion sizes in the United States have increased markedly in the past several decades. For example, from 1977 to 1996, portion sizes increased by 60 percent for salty snacks and 52 percent for soft drinks. Importantly, larger product portion sizes and larger servings in restaurants and kitchens consistently incre...
Doesn't the speed of light disprove Fermi's paradox?	When discussing the Fermi paradox, people usually only talk about civilizations in the Milky Way galaxy. The distance between galaxies is far to great to consider an inter-galactic civilization (though it may be possible). The diameter of the stellar disk of the Milky Way is only about 100,000 light-years. So if a civ...	[ "In 1962 J. G. Fox pointed out that all previous experimental tests of the constancy of the speed of light were conducted using light which had passed through stationary material: glass, air, or the incomplete vacuum of deep space. As a result, all were thus subject to the effects of the extinction theorem. This im...
is taking a shot of 100 proof alcohol the same as taking 1.25 shots of 80 proof?	Essentially yes. Except for the additional water in the 80 proof alcohol. But there is just as much alcohol in both shots so it will have the same effect on your blood alcohol content.	[ "The concentration of alcohol in a beverage is usually stated as the percentage of alcohol by volume (ABV, the number of milliliters (ml) of pure ethanol in 100 ml of beverage) or as \"proof\". In the United States, \"proof\" is twice the percentage of alcohol by volume at 60 degrees Fahrenheit (e.g. 80 proof = 40...
why do humans start getting body odor after they go through puberty?	Basically (the way I was taught this at least) you have two major types of sweat glands, apocrine and eccrine. Sweat produced by eccrine glands is mostly water. Apocrine sweat is more oily and contains a whole bunch of other stuff (which I won't get into). So bacteria can metabolize the components of apocrine sweat far...	[ "The average beginning of pubarche varies due to many factors, including climate, nourishment, weight, nurture, and genes. First (and often transient) pubic hair resulting from adrenarche may appear between ages 10-12 preceding puberty.\n", "Before puberty effects of rising androgen levels occur in both boys and ...
Do bone conduction earphones protect hearing?	There's no reason to believe that they would. Hearing loss is usually caused by damage to the inner ear, which is still getting as much sound exposure with bone conduction as it would through the normal path of sound.	[ "It is a semi-implantable under the skin bone conduction hearing device coupled to the skull by a titanium fixture. The system transfers sound to the inner ear through the bone, thereby bypassing problems in the outer or middle ear. Candidates with a conductive, mixed or single-sided sensorineural hearing loss can ...
why do circles tesselate hexagonally?	It's all geometry. Assuming equal radii between all circles, if you place them in a way that they don't intersect but touch each other at exactly one point (tessellating) and you start with just 3 circles, those circles form a triangle shape. If you connect the centerpoints of those circles, it forms an equilateral tri...	[ "A study by David George Kendall used the techniques of shape analysis to examine the triangles formed by standing stones to deduce if these were often arranged in straight lines. The shape of a triangle can be represented as a point on the sphere, and the distribution of all shapes can be thought of as a distribut...
Where do vegetables and fruit/nut bearing plants get their vitamins and minerals?	They get all the minerals they need from the soil. Vitamins for plants aren't the same necessarily as our vitamins, because a vitamin is something the organism needs to survive but cannot produce on its own (vitamin D is not a true vitamin to us). So, for example, plants can produce vitamin C (ascorbic acid) through a...	[ "Vitamins and minerals are required for normal metabolism but which the body cannot manufacture itself and which must therefore come from external sources. Vitamins come from several sources including fresh fruit and vegetables (Vitamin C), carrots, liver (Vitamin A), cereal bran, bread, liver (B vitamins), fish li...
What's the noise a formula 1 makes when it changes gears?	It's most likely a backfire. When the car is accelerating its at full throttle/load, and the engine runs out of power, so it's time to change gears. imagine going from full throttle to no throttle (changing gears) then back to full throttle. The bang u hear is unburnt fuel exploding in the exhaust after its left the c...	[ "BULLET::::- Transmission problems were tackled by adding a further mounting-point (making five) for the whole engine and transmission assembly at the back of the gearbox where it was supported by an extra chassis cross-member. The transmission made a significant humming noise while in neutral and there were diffic...
what determines how internet lag in different games looks?	Male programmer type guy here. It just depends on how the programmers who made the game decided to handle the case where the game isn't getting updates from the server. Some games leave the character in place, and then warp him when the updates resume. Others avoid the warp by having the character fly from their old po...	[ "Since the game requires information on the location of other players, there is sometimes a delay as this information travels over the network. This occurs in games where the input signals are \"held\" for several frames (to allow time for the data to arrive at every player's console/PC) before being used to render...
In the United States, have there been any particularly strong Vice Presidents, and how was The Senate different under them?	In addition to Calhoun, John Adams regularly presided over the Senate and partook in debates, and beats Calhoun by one vote for the most tie breaks. That said, while they are the nominal head of the Senate, the Constitution also says that the House and Senate get to write their own procedural rules in Article I, Sect...	[ "He served as one of several alternating presidents pro tempore of the United States Senate during the 62nd Congress (1911 to 1913), as part of a compromise under which Bacon and four senators from the Republican majority rotated in the office because no single candidate in either party was able to secure a majorit...
Do black holes really vary in size or does the collapsed point in space just vary in intensity?	Every amount of mass has some radius that, were it all to be compressed within the radius, it would form a black hole. This is called the Schwartzchild radius, and it's calculated by the formula r=2GM/c^2 . G is the gravitational constant, and c is the speed of light. These are both constant, so the math works out the ...	[ "In general relativity, if a star collapses to a size smaller than its Schwarzschild radius, an event horizon will exist at that radius and the star will become a black hole. Thus, the size of a preon star may vary from around 1 metre with an absolute mass of 100 Earths to the size of a pea with a mass roughly equa...
why do strange graphical effects sometimes occur when alt+tabbing a computer game?	It's because the game takes up the majority of your computer's resources and stays at the forefront. Your computer needs to load in all the other stuff that the OS and other programs need before you can use them.	[ "\"Glitching\" is also used to describe the state of a video game undergoing a glitch. The frequency in which a game undergoes glitching is often used by reviewers when examining the overall gameplay, or specific game aspects such as graphics. Some games such as Metroid have lower review scores today because in ret...
How much of time dilation is due to the gravity well versus relative velocity?	You can indeed separate the two effects if the field is weak. I've done the explicit computation for the orbit of Mercury around the sun [here](_URL_0_). It turns out that in a circular orbit the time dilation due to the orbital speed is exactly half the gravitational time dilation. P.S.: GPS satellites are not in ...	[ "In 2010, Chou \"et al\". performed tests in which both gravitational and velocity effects were measured at velocities and gravitational potentials much smaller than those used in the mountain-valley experiments of the 1970s. It was possible to confirm velocity time dilation at the 10 level at speeds below 36 km/h....
how exactly is the “stop/start” automatic engine feature in newer cars “better”?	Barely any wear and tear, better for the environment as all that time you spend not moving while the engine running is time that CO2 and pollutants are spewing out when they don't need to be. Multiply all that time by millions and millions of cars and you have a significant CO2 saving. Saves fuel and thus cash too.	[ "From 2011, Stop/Start was added to certain engines (engines with (S/S) are bold in CO2 column), a cleaner, more powerful 1.7 CDTI auto was added, and the petrol engines became slightly more efficient. A six speed automatic gearbox became available for the 1.4T (120) petrol engine.\n", "The automatic transmission...
how do all the bodies, tanks etc. get cleaned off the battlefields?	Usually they don't. Outside of Kursk you can take a spade out West of the city and dig down just a few inches to human remains, shell casings, etc. Vehicles were only removed if they were salvageable or were in the way. After the war civilians gleaned the site for years for scrap but anything else was just abandoned...	[ "To this day, the remains of missing soldiers are still found in the countryside around the town of Ypres. Typically, such finds are made during building work or road-mending activities. Any human remains discovered receive a proper burial in one of the war cemeteries in the region. If the remains can be identified...
why does our body need uv to create vitamin d when uv exposure increases our risk of skin cancer?	UV light is an energy source, since humans are automatically exposed in varying degrees to this energy source we have evolved to make use of the "free" energy to create vitamin D. We have also evolved to darken the skin to prevent over exposure to UV which would increase risks of skin cancer. Only animals like naked mo...	[ "The sun's UV radiation is both a major cause of skin cancer and the best natural source of vitamin D. The risk of skin cancer from too much sun exposure needs to be balanced with maintaining adequate vitamin D levels. Vitamin D deficiency in Australia has also greatly increased, since sunblock also reduces vitamin...
Is there any particular reason why so many people in the United States claim Cherokee ancestry?	Hello. I'm a mod over on /r/IndianCountry, the second largest and most active Native American subreddit. We recently constructed an FAQ [with a section that answers this specific question](_URL_1_) and links to several sources to back it up. I would like to note, though, that this is more of a social question with a h...	[ "Gregory D. Smithers wrote, a large number of Americans belong in this category: \"In 2000, the federal census reported that 729,533 Americans self-identified as Cherokee. By 2010, that number increased, with the Census Bureau reporting that 819,105 Americans claimed at least one Cherokee ancestor.\" By contrast, a...
how does the new iphone voice command system (siri) work?	I don't know the exact details, but I do know that any query made to the system goes to remote servers with the voice command. There, the technology across multiple servers parses your voice to determine exactly what you say (some say the original creators of the voice recognition technology, Nuance, [is still primari...	[ "Apple added Voice Control to its family of iOS devices as a new feature of iPhone OS 3. The iPhone 4S, iPad 3, iPad Mini 1G, iPad Air, iPad Pro 1G, iPod Touch 5G and later, all come with a more advanced voice assistant called Siri. Voice Control can still be enabled through the Settings menu of newer devices. Siri...

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