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why would we ever care about the distinction of a newtonian fluid and a non-newtonian fluid? (i put this with an engineering flair because i want to know if there’s any practical use, not theoretical)	Imagine you're trying to fill a mold with a material. You'd likely want to do that as fast as you can. Well, what happens if the material doesn't behave like a Newtonian fluid? It becomes much more difficult to predict how the mold will fill without extensive experimentation. You can also get neat things like _URL_1_...	[ "Newtonian fluids are the simplest mathematical models of fluids that account for viscosity. While no real fluid fits the definition perfectly, many common liquids and gases, such as water and air, can be assumed to be Newtonian for practical calculations under ordinary conditions. However, non-Newtonian fluids are...
Would supersonic air flowing across a wing fixed to the floor in a lab produce a constant sonic boom?	A sonic boom is the perceptual phenomenon caused by the passage of a shock wave over the human ear. Every object that is going faster than the speed of sound in a medium has an associated shock wave attached to or very near the object. This shock wave is always there once the object reaches a speed faster than Mach 1. ...	[ "The aerodynamics of supersonic flight is called compressible flow because of the compression (physics) associated with the shock waves or \"sonic boom\" created by any object travelling faster than sound.\n", "The later shock waves are somewhat faster than the first one, travel faster and add to the main shockwa...
What is the connection between Majorana Mass and a Majorana Particle?	If you give a Majorana mass to a "normal" four-component spinor, so making it satisfy the Majorana equation, you obtain two particles. They are antiparticles of eachother and must be electrically neutral. Only when you supplement the Majorana condition, that is that the spinor is its own charge conjugate, you ge...	[ "However, the right-handed sterile neutrinos introduced to explain neutrino oscillation could have Majorana masses. If they do, then at low energy (after electroweak symmetry breaking), by the seesaw mechanism, the neutrino fields would naturally behave as six Majorana fields, with three of them expected to have ve...
Floating Feature: Close Up Shop and Celebrate History Coming to an End as 'The Story of Humankind' Concludes With Volume XIII from 1947 to 2000 CE!	The 1980s neo-liberal reforms as an attempt to eliminate the military-industrial complex: part 1 Now that should be a provocative title! Over the 1970s, 1980s, and 1990s, there were pro-market reforms across much of the world. These reforms were and are highly controversial. My purpose in this post is to give a h...	[ "The longest of the stories is also called \"Half a Life\" and tells the story of a Russian woman kidnapped by an alien spacecraft in the years following the second world war. In a distant, but unspecified future, human cosmonauts discover the alien ship floating in space, a derelict. Entering the ship, they soon r...
Can theories be proven or is it that they have just failed to be disproved?	You are correct. The general answer for the scientific method is that nothing can be proven, only disproven. However, once a hypothesis has passed enough experimental tests that the only other competing hypothesizes are clearly wrong, then the hypothesis becomes a "theory" meaning it has a great deal of acceptance...	[ "To the Sceptics, none of the contending theories, proposed by limited intellect, can be known to be true, since they are mutually contradictory. Also, any new theory is bound to contradict existing theories, and hence cannot be true. Hence nothing can be known to be true. Thus the Sceptics conclude that the contra...
Are there any examples of animals practicing medicine in the wild?	There are parrots in the amazon that eat fruit that is toxic to them. Every evening they fly to a riverbank with an exposed clay cliff and eat some of the clay. The minerals in the clay neutralise the poison. I wish I could remember more details, like the species of parrot and the specific type of fruit.	[ "Some animal parts used as medicinals can be considered rather strange such as cows' gallstones, hornet's nests, leeches, and scorpion. Other examples of animal parts include horn of the antelope or buffalo, deer antlers, testicles and penis bone of the dog, and snake bile. Some TCM textbooks still recommend prepar...
Can someone lend a neutral analysis of Mao, the Cultural Revolution, and the Great Leap Forward?	Well I will be honest I don't have anything more than an undergraduate's understanding of China, having taken a few classes on the subject, but I have a few things to say here. First the problem with the article you linked is that it is overwhelmingly arguing from a position of "well the evidence that this happened mi...	[ "The official view aimed to separate Mao's actions during the Cultural Revolution from his \"heroic\" revolutionary activities during the Chinese Civil War and the Second Sino-Japanese War. It also separated Mao's personal mistakes from the correctness of the theory that he created, going as far as to rationalize t...
Is there any peculiarity about the places a supercontinent splits (e.g. the Atlantic coastlines of Africa and South America) or is it just about the subterranean magma flow?	There are a couple of things that (potentially) contribute to where the rift system that breaks up a supercontinent will localize, but all of them will generally lead to the rift system initiating broadly in the center of the supercontinent and roughly coincident with where the supercontinent was joined together in the...	[ "In plate tectonics theory during the breakup of a continent, three divergent boundaries form, radiating out from a central point (the triple junction). One of these divergent plate boundaries fails (see aulacogen) and the other two continue spreading to form an ocean. The opening of the south Atlantic Ocean starte...
studying vs fun	Feel good now many times or feel good once later in the future? Your brain prefers the former. It comes down to gratification frequency in your brain. The frequency of dopamine release you get from video games is shorter in video games since you can get instantly rewarded for your tasks, feeding into a cycle. Think ab...	[ "\"Fun School Specials\" is a set of educational games, created in 1993 by Europress Software, consisting of four different games. Upon demand, Europress designed each game specifically with a certain major topic to add depth to spelling, maths, creativity and science, respectively and comply fully with the Nationa...
Would it be possible to make a device to see radio/TV/cell phone signals, the same way an infrared camera can "see" heat?	This is used a lot in astronomy [pic](_URL_0_)	[ "There are two infrared-based approaches. In one, an array of sensors detects a finger touching or almost touching the display, thereby interrupting infrared light beams projected over the screen. In the other, bottom-mounted infrared cameras record heat from screen touches.\n", "The use of an infrared sensor to ...
why is it difficult for the investigators to find the flight recorder from the downed malaysia flight 17 , when there is supposed to be a beacon pin-pointing its location ?	Finding the proverbial black box is simple if it's left where it is. The moment someone picks it up, removes the pinger, and sticks it on a truck -- it becomes hard to find. Rebels (or Russians, I don't know that there's a practical way to distinguish) have been all over the site removing "stuff". The working hypothes...	[ "The aircraft's flight recorders were sent to the Australian Transport Safety Bureau for analysis. Initial statements by the authorities suggested that the pilots mistook a road for the airport's runway in low visibility.\n", "However in case the flight recorders shall become available to the western countries th...
Foggy London vs polluted Beijing	fyi, you'll find some previous discussions on this in the FAQ * [Air pollution](_URL_0_)	[ "Due to Beijing's high-level of air pollution, there are various readings by different sources on the subject. Daily pollution readings at 27 monitoring stations around the city are reported on the website of the Beijing Environmental Protection Bureau (BJEPB). The American Embassy of Beijing also reports hourly fi...
Did the Barbarians of the Classical Roman Era field any navies and if so was there ever any engagements between them and the Roman Empire?	The Veneti, a Gallic tribe from Brittany in modern France, posed quite a naval threat to Caesar during the Gallic Wars. They had several coastal citadels that couldn't be sieged out, as the strong Venetian (no, not that Venetian) navy protected the supply ships from across the channel in Britain. A fascinating aspe...	[ "The barbarians comprised war bands or tribes of 10,000 to 20,000 people,[5] but in the course of 100 years they numbered not more than 750,000 in total, compared to an average 39.9 million population of the Roman Empire at that time. Although invasion was common throughout the time of the Roman Empire,[6] the peri...
if everyone says girls mature more quickly than boys, why do boys seem to have a higher sex drive than girls while teenagers?	because sex drive and maturity have nothing to with each other?	[ "Studies have shown that most high school girls are more interested in a relationship compared to high school boys, who are mostly interested in sex. Young women tend to be honest about their sexual encounters and experiences, while young men tend to lie more often about theirs. Another study shows that once a pers...
If a person gains weight gradually, will their leg muscles (quadriceps, hamstrings, calves etc) grow proportionally to support the added weight?	They would have to, otherwise you wouldn't be able to walk. On the other hand, it depends on what kind of weight you are gaining. Obviously gaining muscle mass will cause your muscles to grow. On the other hand, gaining a lot of weight in the form of fat has other consequences. The fat gets deposited all over the place...	[ "Individuals with this disorder typically experience progressive muscle weakness of the leg and pelvis muscles, which is associated with a loss of muscle mass (wasting). Muscle weakness also occurs in the arms, neck, and other areas, but not as noticeably severe as in the lower half of the body. Calf muscles initia...
why do people's voices sound higher pitched in older recordings? were the vocal tastes for higher pitched voice in the past or was it due to the recording equipment used?	Bass frequencies require more energy to record and reproduce than do higher ranges of audio. Old recording equipment didn't have the types of improvements we've made since then. The diaphragm in a modern microphone is much more sensitive to input and can record a sound with much less intensity than older equipment. The...	[ "Some evidence exists of vocal fry becoming more common in the speech of young female speakers of American English in the early 21st century, but its frequency's extent and significance are disputed. Researcher Ikuko Patricia Yuasa suggests that the tendency is a product of young women trying to infuse their speech...
Do mental illnesses run in families? Will they be the same mental illness or can they vary between each offspring?	There is a genetic role in some forms of mental illness like schizophrenia for example. There's also a lot of environmental factors that cause or worsen mental illness, like physical/emotional abuse/neglect, malnutrition, traumatic life events, etc. There are usually many factors at play and no case is exactly the same...	[ "A similar study on the mental health of single mothers attempted to answer the question, \"Are there differences in the prevalence of psychiatric disorders, between married, never-married, and separated/divorced mothers?\" Statistically, never married, and separated/divorced mothers had the highest regularities of...
How did Polar Bears survive the Medieval Warm Period?	It [wasn't that warm](_URL_0_) compared to today.	[ "In the Ice Age (which included warm spells), mammals such as the woolly mammoth, wild horse, giant deer, brown bear, spotted hyena, Arctic lemming, Norway lemming, Arctic fox, European beaver, wolf, Eurasian lynx, and reindeer flourished or migrated depending on the degree of coldness. The Irish brown bear was a g...
Who were Turkish Sultans descended from?	As strange as it may seem, your story is essentially correct. Ottoman Sultans didn't marry, and instead had lowborn concubines. I'm not sure how many of the Sultan's mothers were European, but some were, yes. And indeed since only the direct male line is the family of the Sultans, the vast majority of later Sultans' an...	[ "This is a list of the biological mothers of Ottoman sultans. There were thirty-six sultans of the Ottoman Empire in twenty-one generations. (During early days the title \"Bey\" was used instead of \"Sultan\") Throughout 623-years history the sultans were the members of the same house, namely the House of Ottoman (...
The origins of the Abrahamic religions.	Can I ask a clarification question before my answer gets deleted? Are we allowed to use religious texts such as the old testament or Koran as sources while we acknowledge the disputed historicity? In particular, the book of Joshua?	[ "Abrahamic religions are those religions deriving from a common ancient tradition and traced by their adherents to Abraham (circa 1900 BCE), a patriarch whose life is narrated in the Hebrew Bible/Old Testament, where he is described as a prophet (Genesis 20:7), and in the Quran, where he also appears as a prophet. ...
Is the Multiverse a "God of the Gaps"-type explanation for something we don't understand?	I think that this links directly to the question of the place of falsifiability in science more broadly, which is something that physicists are currently fighting over. [Some have argued](_URL_1_) that the multiverse theory, among others, fails a basic test of scientific rigor in being falsifiable. [Others](_URL_0_) ha...	[ "The multiverse is a series of parallel universes in many of the science fiction and fantasy novels and short stories written by Michael Moorcock. (Many other fictional settings also have the concept of a multiverse.) Central to these works is the concept of an Eternal Champion who has potentially multiple identiti...
why can't i, a nearsighted person, use a vr headset without my glasses? shouldn't everything still be clear since it's just a screen close to my eyes?	Glasses refocus light to correctly hit misshapen eyes. Each person, sometimes each eye, will have different corrections that need to be made. If a "normal" sighted person wears someones prescription glasses everything will look distorted. The lenses in a VR set also refocus light, but are designed to simulate distance...	[ "VR headsets may regularly cause eye fatigue, as does all screened technology, because people tend to blink less when watching screens, causing their eyes to become more dried out. There have been some concerns about VR headsets contributing to myopia, but although VR headsets sit close to the eyes, they may not ne...
why, when watching a live tv program, is there a delay on a screen in the shot when it shows the same program as being broadcast	Because there is a time delay in capturing video and displaying it. The live view is capturing a display of itself. At one frame in time, that light information from the camcorder gets converted to electrical signals, decoded, then sent to be displayed elsewhere. This will take several frames of time before it pops up...	[ "In radio and television, broadcast delay is an intentional delay when broadcasting live material. Such a delay may be short (often seven seconds) to prevent mistakes or unacceptable content from being broadcast. Longer delays lasting several hours can also be introduced so that the material is aired at a later sch...
why do people's ears tend to get hot when they drink alcohol?	Alcohol causes your blood vessels to expand which increases circulation. This is more noticeable where there is very little skin and muscle to hide the changes. Like your ears.	[ "Alcohol may worsen asthmatic symptoms in up to a third of people. This may be even more common in some ethnic groups such as the Japanese and those with aspirin-induced asthma. Other studies have found improvement in asthmatic symptoms from alcohol.\n", "Alcohol abuse can cause a susceptibility to infection afte...
Why are older geological layers at the bottom and newer ones at the top?	An important concept is that of [isostatic subsidence](_URL_0_). Let's imagine a really simple scenario. Imagine a lake whose level is around sea-level. It is receiving sediment from rivers draining mountains and other surrounding upland areas. Let's say that we deposit 1 cm of sediment in that lake. That 1 cm of sedim...	[ "That new rock layers are above older rock layers is stated in the principle of superposition. There are usually some gaps in the sequence called unconformities. These represent periods where no new sediments were laid down, or when earlier sedimentary layers were raised above sea level and eroded away.\n", "When...
What was the journey to Auschwitz like?	What they were referring to as "goods wagons" were likely the trucks which were in this case used to take people from factories to centers from which they were deported to Auschwitz in cattle cars. The Nazis usually deported Jews to extermination camps such as Auschwitz Birkenau in cattle cars with very horrible condit...	[ "The trip was organized to both commemorate the 50th anniversary of the end of World War II as well as to be witness to the suffering in contemporary war zones. The group walked from Auschwitz to Vienna, then travelled through Croatia, Bosnia and Serbia. They crossed the front lines of the Bosnian war in Mostar and...
Was American Artillery more effective and decisive than German Artillery in WW2? If so, why?	[This response by /u/vonadler is exactly what you are looking for.](_URL_0_)	[ "Although also frequently out-ranged by their German counterparts, American artillery built up a reputation for effectiveness and the infantry increasingly relied on the artillery to get them forward. The War Department General Staff ignored the Army Ground Force's recommendations for a powerful heavy artillery arm...
Why does it seem like early American civilizations' (Maya, Olmec, Aztec) art/architecture is much less developed or much less impressive than that of early Europe and Asia?	This is a common misconception, in truth mesoamerican and south american cultures were very advanced, just in ways that were different than what is typically thought of as "advanced". Early American civilizations had very complex construction and architecture techniques as well as metallurgy and textiles. When people...	[ "They were a forerunner of later cultures such as Teotihuacan, north of Mexico City, the Zapotecs in Oaxaca and the Mayas in southern Mexico, Belize and Guatemala. While empires rose and fell, the basic cultural underpinnings of the Mesoamerica stayed the same until the Spanish conquest of the Aztec Empire. These i...
Neutron Star Density question. (Chemistry/Astrophysics)	The mass density of a neutron star is comparable to the mass density of the nucleus of an atom. In ordinary matter, the density is much less, because the mass of an atom is almost all in the nucleus, but the nucleus takes up only a tiny fraction of the volume of an atom, so the density of ordinary matter is vastly les...	[ "Neutron stars have overall densities of to ( to times the density of the Sun), which is comparable to the approximate density of an atomic nucleus of . The neutron star's density varies from about in the crust—increasing with depth—to about or (denser than an atomic nucleus) deeper inside. A neutron star is so den...
why are addresses depicted the way they are, and not postcode/zipcode first? surely this would be easier?	Pretty much you answered it yourself. It's done that way because it's traditional. People haven't felt a need for change because there were no problems with the old way. The cost to promote the change, and the cost of potential delays or disruptions from confusion or inconsistency, would outweigh the negligible benefit...	[ "Postal designations for place names become \"de facto\" locations for their addresses, and as a result, it is difficult to convince residents and businesses that they are located in another city or town different from the \"preferred\" place name associated with their ZIP Codes. Because of issues of confusion and ...
In late medieval England, how were MPs chosen for the House of Commons?	Ah the pre reform house of commons. As always the answer is it depends which ones. Essentially you had 2 main forms of MPs. The knights of the shires that represented counties and those that represented urban centres. Then you had varies other MPs such as those that represented the Cinque Ports (University constitue...	[ "The House of Commons of the Kingdom of England evolved from an undivided parliament to serve as the voice of the tax-paying subjects of the counties and of the boroughs. Knights of the shire, elected from each county, were usually landowners, while the borough members were often from the merchant classes. These me...
how can monsanto get away with virtually suing any farmer? how can the non-gmo farmer protect him/herself?	You have to go out of your way to get sued. Here's what happens... It's suspected that you have GMO crops on your land, this is usually reported by other farmers or by seed elevators that buy crops from farmers. The owners of the technology (Monsanto, usually (thanks to their patent portfolio)...but can be Dupont/Dow...	[ "Those who opposed the provision referred to it as the \"Monsanto Protection Act\", on the premise that it \"effectively bars federal courts from being able to halt the sale or planting of controversial genetically modified (aka GMO) or genetically engineered (GE) seeds, no matter what health issues may arise conce...
How does cortisone work?	I think you mean cortisol, rather than cortisone. The two are interconverted in the cell by an enzyme system (11- beta HSD 1 and 2) and cortisone is actually much less active than cortisol. Cortisol circulates in the blood bound to corticosteroid binding globulin, a carrier molecule. About 96% of cortisol is bound, bu...	[ "Cortisol is a stress hormone secreted by the adrenal gland, which makes up part of the hypothalamic-pituitary-adrenal (HPA) axis. It is typically released at periods of high stress designed to help the individual cope with stressful situations. Cortisol secretion results in increased heart rate and blood pressure ...
Are the stars in the big dipper closer to Earth than other stars in the night sky and is that how they came to be a constellation?	[This image](_URL_0_) shows the Big Dipper head on, and from the side. Distances to astronomical objects are essentially impossible to judge from a human perspective on Earth. Stars that are much brighter, but further away, can far outshine nearby dim stars. A star's location on the sky or in a constellation usually ha...	[ "If the Sun were to be observed from the Alpha Centauri system, the nearest star system to ours, it would appear to be a 0.46 magnitude star in the constellation Cassiopeia, and would create a \"/W\" shape instead of the \"W\" as seen from Earth. Due to the proximity of the Alpha Centauri system, the constellations...
Navigation in bombers during world war 2. Were the navigators able to compute the route on their own or their work was mostly handled by electronical devices?	Mostly map work and instruments - at least early on - which is why the Blackouts actually worked as a measure to reduce the accuracy of Bomber attack. There are examples of long-range guidance by electronics; however, the Luftwaffe used radio transmitters and modified Lorentz blind-landing sets (short range radio recei...	[ "The first distance-based navigation system was the German Y-Gerät blind-bombing system. This used a Lorenz beam for horizontal positioning, and a transponder for ranging. A ground-based system periodically sent out pulses which the airborne transponder returned. By measuring the total round-trip time on a radar's ...
what happens to our world (including its inhabitants) if the worst case scenario happens with global warming. i'm not even sure how to define worst case scenario. melting of polar ice caps? temperature going up globally 10 degrees (f)?	The ice caps are going to melt. It is a question of when. The models use are always failing for predicting how much sea ice is melting. There are unknown factors. We estimate based on what we know and what we guess. The unknowns can kill us. As things warm up, we know they will, there will be more carbon dioxide rele...	[ "António Guterres the Secretary-General of the United Nations told “We’re running out of time. To waste this opportunity would compromise our last best chance to stop runaway climate change. It would not only be immoral, it would be suicidal.” The IPCC special report is a stark acknowledgment of what the consequenc...
Is there a "filter" that can shift infrared light into the visible spectrum?	Not all night vision goggles work that way. The more traditional approach is to use the photoelectric effect - incoming IR photons hit a screen, which emits electrons. These are then accelerated through an electric field and strike another screen, which causes the emission of even more electrons, and these then strike ...	[ "For observing the sun, a much narrower band filter can be made from three parts: an \"energy rejection filter\" which is usually a piece of red glass that absorbs most of the unwanted wavelengths, a Fabry–Pérot etalon which transmits several wavelengths including one centred on the H-alpha emission line, and a \"b...
the mess of weird text you get when you turn a .png/.jpg file into a .txt	In the end, all files are just 1s and 0s. A jpg is only a jpg because the program opening it knows how to interpret those 1s and 0s as an image. But notepad doesn't know how to interpret it as an image. It just assumes anything you open in it is meant to be text. So it interprets the data as if it was text. But sinc...	[ "The next graphic shows the contents of such a minimal PNG file, representing just one red pixel. The PNG signature bytes and the individual chunks are marked with colors. On the left side, the byte values are shown in hex format, on the right side as their equivalent characters from ISO-8859-1 with unrecognized an...
how do companies get paid from credit cards?	Short answer: They receive money in chunks throughout the month usually on a daily basis but it is on a 2 day delay. The company has a bank that they process credit cards through, this is called the acquirer bank. The card the customer uses is also backed by a bank, this is called the issuer bank. When the merchant...	[ "Within the United States, credit card transactions are controlled by four main financial institutions: Visa, MasterCard, American Express, and Discover, making it an oligopoly. Credit cards work as a two-sided market, with the institutions providing benefits to consumers (by allowing them to access lines of credit...
Why did Staten Island remain mostly residential, and not develop more like Manhattan did?	Totally got this one. Native Staten Islander here, who has done research. I'm on my phone, so I cannot provide links at the moment though. First, one has to realize that Staten Island is the least populous borough--I think the current population is only about 500-600k. Staten Island historically has also been sparsely...	[ "Although Staten Island as a whole remained largely residential and less densely populated and developed than the surrounding region, the inhabitants of the region favored consolidation with the greater metropolis. In 1898, Staten Island was consolidated with New York City, and this move accelerated development of ...
After reverse transcriptase creates a provirus, how does a retrovirus differ from a single-stranded DNA virus in its activity?	There are two major reasons, to my knowledge, that retrovirus replication using a provirus intermediate is different than an single stranded DNA virus. One, proviruses directly integrate into the chromosomal genome, while DNA viruses (usually) integrate extrachromosomally ([there have been some reports that Herpes vir...	[ "The retrovirus begins the journey into a host cell by attaching a surface glycoprotein to the cell's plasma membrane receptor. Once inside the cell, the retrovirus goes through reverse transcription in the cytoplasm and generates a double-stranded DNA copy of the RNA genome. Reverse transcription also produces ide...
Why does our skin get numb when we're cold?	Blood flow to exterior arteries is restricted to keep the internal organs warm.	[ "When exposed to cold temperatures, the blood supply to the fingers or toes, and in some cases the nose or earlobes, is markedly reduced; the skin turns pale or white (called pallor) and becomes cold and numb.\n", "The most common, everyday cause is temporary restriction of nerve impulses to an area of nerves, co...
Was there any presidential republics like the United States before the United States existed?	There were prior examples of mixed regimes. Aristotle advocated for them and the Roman Republic may be an example with its consuls, senators and assemblies. However, no prior regime deeply resembled the US. The US arguably drew more on ideas than examples in its creation. The separation of powers, of which the US p...	[ "In the example of the United States, the original 13 British colonies became independent states after the American Revolution, each having a republican form of government. These independent states initially formed a loose confederation called the United States and then later formed the current United States by rat...
why do cats love to push things off tables?	I did a report for an animal behavior class in undergrad on animal play. It overwhelmingly focused on younger animals and why it is such a common trend across species to mess around with each other and fuck around with objects. As far as playing with each other, it seems to be a natural inclination to enjoy it but the ...	[ "Jackson teaches that cats are territorial, needing spaces within homes to call their own and that they send signals when they no longer desire petting, a condition he refers to as \"overstimulation.\" Cats do not like being cornered and lash out when overstimulated. Certain cats (whom he calls \"tree-dwelling cats...
I know that in the middle ages many towns were rather small (often the largest still only consisting of tens of thousands of people). How vital to the national economy were towns? What sort of professions were people practising there and were there any that weren't as common in more rural locations?	"How important were towns" is kind of a tough question to answer, because the existence/increase of towns is both a sign and a cause of overall exonomic restructuring over the later Middle Ages. Towns were essential to the economic system they were a part of/helped create. You can say something like by 1300, about 65% ...	[ "A few towns in the Low Countries dated back to Roman times, but most had been founded from the 9th century onward. The oldest were in the Scheldt and Meuse areas, with many towns in what's now the Netherlands being much younger and only dating from the 13th century. From early on, the Low Countries began to develo...
when i uninstall a program using an unistallation .exe included in the program's folder, how is that .exe capable of uninstalling itself?	It is not possible for a Windows executable to delete itself. This is due to the way that executable files are loaded by Windows. Instead of reading the entire file into RAM (as some commenters have suggested), Windows maps the file into memory - it is more accurate to say it maps portions of the file to different ...	[ "The term \"decompiler\" is most commonly applied to a program which translates executable programs (the output from a compiler) into source code in a (relatively) high level language which, when compiled, will produce an executable whose behavior is the same as the original executable program. By comparison, a dis...
how do items like peelers, graters, scissors etc. stay sharp but knives constantly need to be sharpened?	It's not that they stay sharp, but for their purpose they don't need to be as sharp. They are also subject to lesser forces and materials than a knife, which might be used to cut a carrot one minute and a tomato the next. The knife's edge will also get rolled over and dulled by the cutting board/surface and how it is u...	[ "Different knives are sharpened differently according to grind (edge geometry) and application. For example, surgical scalpels are extremely sharp but fragile, and are generally disposed of, rather than sharpened, after use. Straight razors used for shaving must cut with minimal pressure, and thus must be very shar...
How did someone such as Ibn Battuta (practically and logistically) travel, and keep travelling?	While I cannot speak for Ibn Battuta's case (I think he is a really interesting figure though), you need to break away from the 20-21st century capitalist mentality that every service is paid for using cash currency. My guess (and I will defer to scholars of the Islamic world) is that given his high status he would hav...	[ "Scholars do not believe that Ibn Battuta visited all the places he described and argue that in order to provide a comprehensive description of places in the Muslim world, he relied on hearsay evidence and made use of accounts by earlier travellers. For example, it is considered very unlikely that Ibn Battuta made ...
If time is infinite...	> If time is infinite, would it be fair to say that every configuration of the universe happens at least once, That conclusion does not necessarily follow from that premise. > similar to how if the set of natural numbers is infinite, every number is in this set? Of course the set of natural numbers contains every ...	[ "In \"Did the World Have a Beginning?\" he argues that the temporal world cannot always have existed. An actual infinity is impossible, he reasons, because infinity is a potential value that cannot be reached. A line, for example, may be extended infinitely—that is, without a limit—but at no point will the actual m...
Why doesn't gravity work on small scales?	Gravity is a very, very, very, very weak force. To get appreciable gravitational effects, therefore, you need to have very large objects, like a planet. There is a gravitational force between you and that building you walk by, but it is absolutely tiny.	[ "As the sizes got smaller, one would have to redesign some tools, because the relative strength of various forces would change. Although gravity would become unimportant, surface tension would become more important, Van der Waals attraction would become important, etc. Feynman mentioned these scaling issues during ...
Why is carbonated water effervescent while other gas-liquid solutions (e.g. vinegar, hydrochloric acid, etc.) are not?	Two things: 1. While carbondioxide can disolve in water it can also react following CO2 + H2O -- > H(+) + HCO3(-). This means the gas can be stored as ions and react back into gas when the relation between the amounts of CO2 and HCO3(-) changed. 2. Carbonated drinks are made under pressure. At say 10 bar a lot more ...	[ "By itself, carbonated water appears to have little impact on health. While carbonated water is somewhat acidic, this acidity can be partially neutralized by saliva. A study found that sparkling mineral water is slightly more erosive to teeth than non-carbonated water but is about 100 times less erosive to teeth th...
why shouldn’t you eat anything before going into a swimming pool?	People used to think that it would cause cramps, which could result in you drowning in the pool. This is an old wives tale - it doesn't cause cramps no matter how soon you swim after eating. However, it does have the benefit of keeping food out of and away from pools, thus keeping the pools cleaner, so no one is real...	[ "Nonetheless, licking does play a role for humans. Even though humans cannot effectively drink water by licking, the human tongue is quite sufficient for licking more viscous fluids. Some foods are sold in a form intended to be consumed mainly by licking, e.g. ice cream cones and lollipops.\n", "BULLET::::- Don't...
why does a computer need to "warm up"?	Because (especially in the case of Windows), the operating system loads and runs just enough components to allow you to log in, and show the desktop, while literally hundreds of drivers and services continue to be loaded and run "in the background" . Older versions of Windows would not allow use until everything was l...	[ "Reducing the heat output of the computer helps reduce noise, since fans do not have to spin as fast to cool the computer. Reduced heat and resulting lower cooling demands may increase computer reliability.\n", "Because high temperatures can significantly reduce life span or cause permanent damage to components, ...
How do anti-diarrheals work? Is a bowel movement is coming from the colon/rectum how does something like Imodium of pepto bismal work so quickly when digestion of food takes hours?	Gastroenterologist here: Short answer - there are multiple mechanisms: 1) Mu Receptor agonists These bad boys are drugs like immodium (loperamide) and lomotil (diphynoxylate and atropine). They work by binding to Mu receptors on the smooth muslcles of the colon. By binding to these receptors the muscles of the co...	[ "As bowel stimulants, enemas are employed for the same purposes as orally administered laxatives: To relieve constipation; To treat fecal impaction; To empty the colon prior to a medical procedure such as a colonoscopy. A large volume of enema can be given to cleanse as much of the colon as possible of feces. Howev...
how do we know how much charge is left in a battery?	_URL_0_ This question has been asked before.	[ "Charge and discharge rates are often given as \"C\" or \"C-rate\", which is a measure of the rate at which a battery is charged or discharged relative to its capacity. The C-rate is defined as the charge or discharge current divided by the battery's capacity to store an electrical charge. While rarely stated expli...
why's it so important to recycle batteries?	We don't want the metals found in batteries in our drinking water. If they go into the trash, the go to the landfill. Water leaching from landfill ends up in someone's glass eventually.	[ "Battery recycling is a recycling activity that aims to reduce the number of batteries being disposed as municipal solid waste. Batteries contain a number of heavy metals and toxic chemicals and disposing of them by the same process as regular trash has raised concerns over soil contamination and water pollution.\n...
Woodrow Wilson had a PHD. Was he addressed as Dr. President?	No—"Mr. President" is not just the name of the job preceded by the traditional male English honorific. It's the actual title of the sitting president, the way something like "your majesty" might be used for a monarch. Edit: /u/The_Alaskan's [comment reply](_URL_4_) notes that "Madam President" would be used by a fema...	[ "BULLET::::- Woodrow Wilson (1210 Eutaw Pl.), President of Princeton University, Governor of New Jersey, and President of the United States. Wilson lived in Bolton Hill during his doctoral studies at Johns Hopkins.\n", "Thomas Woodrow Wilson (December 28, 1856 – February 3, 1924) was an American statesman, lawyer...
what does it mean if a currency is ‘strong’ or ‘weak’	A strong currency is a currency that has an increased value compared to other currencies. But this has little to do with the numerical value of the currencies, despite what other commenters above said. 1 dollar is usually worth 100-120 yen. If the dollar becomes worth 80 yen, then it means the yen has become stronger ...	[ "The weak force is due to the exchange of the heavy W and Z bosons. Its most familiar effect is beta decay (of neutrons in atomic nuclei) and the associated radioactivity. The word \"weak\" derives from the fact that the field strength is some 10 times less than that of the strong force. Still, it is stronger than ...
How do thermophiles survive temperatures that would quickly cook animal tissue?	I found a website that has several different adaptations thermophiles have: _URL_0_ Basically it boils down to having extra-tough proteins that can withstand the higher temperatures without denaturing. The flipside is though, that some of these tougher proteins are only viable at higher temperatures. If the tempera...	[ "There are two explanations for thermophiles being able to survive at such high temperatures whereas mesophiles can not. The most evident explanation is that thermophiles are believed to have cell components that are relatively more stable than the cell components of mesophiles which is why thermophiles are able to...
If the speed of light is constant, how does it "bounce" off of a mirror. Does'nt that imply that the light slowed to a velocity of zero and reversed its momentum?	Well...I'd like to clear up a subtle point in your post's title. You say "if the speed of light is constant" - remember that c is the speed of light in vacuum. The speed of light in a material is less than c, and has to do with the material properties that the light is traveling through (it's NOT due to photon abso...	[ "The formula for radar Doppler shift is the same as that for reflection of light by a moving mirror. There is no need to invoke Einstein's theory of special relativity, because all observations are made in the same frame of reference. The result derived with \"c\" as the speed of light and \"v\" as the target veloc...
slightly new to reddit, why do people post their edits at the bottom of their posts	If you edit a post after a number of minutes it puts an asterisk in the header of the post. Additionally, people generally do it as a form of courtesy, either to not force someone to re-read the entire post and figure out what the altered content is, or to maintain the flow of conversation. That is to say, if you post...	[ "An editor's current position is represented with an editor-specific color/cursor, so if another editor happens to be viewing the same slide, they can see edits as they occur. A sidebar chat functionality allows collaborators to discuss edits. The revision history allows users to see the additions made to a documen...
what is it about orange juice that dulls the taste of alcohol so well?	Ethanol causes a burning sensation because it activates the same [receptors](_URL_0_) as capsaicin. Acids also activate this class of receptors and so drinks like OJ and coke which are acidic will also activate them.	[ "Orange soft drinks (especially those without orange juice) often contain very high levels of sodium benzoate, and this often imparts a slight metallic taste to the beverage. Other additives commonly found in orange soft drinks include rosin and sodium hexametaphosphate.\n", "Common orange juice is made from the ...
the difference between discrimination & prejudice?	Prejudice is a feeling or an opinion, while discrimination is an actual act. Prejudice of course often leads to discrimination. For example, if I believe people of a certain ethnicity are likelier to be shop lifters then I am prejudiced against them, but that doesn't mean I discriminate against them. It's discriminati...	[ "Discrimination is the selection for unfavorable treatment of an individual or individuals on the basis of: gender, race, color or ethnic or national origin, religion, disability, sexual orientation, social class, age, or as a result of any conditions or requirements that do not accord with the principles of fairne...
how are vector illustrations not based on pixels if our screen is made up of pixels?	> So even if we're using a software like Adobe Illustrator, isn't a vector line made up of a bunch of small pixels in actuality? The vector itself is just a bit of math saying "A line exists between point A and point B". The resulting line is displayed using pixels, but the underlying mathematical representation m...	[ "Vector formats are not always appropriate in graphics work and also have numerous disadvantages. For example, devices such as cameras and scanners produce essentially continuous-tone raster graphics that are impractical to convert into vectors, and so for this type of work, an image editor will operate on the pixe...
Have any of the works of Greek & Roman Antiquity been recovered in contemporaneous form, and turned out to differ from their Renaissance-era translations?	Not "first editions" (haha), but ancient copies, certainly. The most common avenue for finding ancient copies is via papyri preserved in Egyptian rubbish dumps, or turned into papyrus-mâché and used in sarcophaguses, though papyri have certainly turned up elsewhere too (e.g. in Herculaneum, as you mention). They're ne...	[ "recovery of lost Greek classics (and, to a lesser extent, Arab advancements on them) following the Crusader conquest of the Byzantine heartlands, revitalized medieval philosophy in the Renaissance of the 12th century, just as the refugee Byzantine scholars who migrated to Italy during and following the Turkish con...
why does wine give such wicked hangovers?	You've got a mild allergy to the grape in that type of wine. Switch types and/or color, and drink more water. Or switch to beer or hard liquor or heroin.	[ "Whether fusel alcohol contributes to hangover symptoms is a matter of scientific debate. A Japanese study in 2003 concluded: \"the fusel oil in whisky had no effect on the ethanol-induced emetic response\" in the Asian house shrew. Additionally, consumption of fusel oils with ethanol suppressed subjects' subsequen...
Why are triangles, squares, and hexagons the only shapes that can tesselate?	Regular polygons are equilateral and equiangular. The only way a regular polygon can tesselate the plane is if some multiple of the interior angle equals 360 degrees. This is the only possible way you can actually fit a multiple of the polygons around each vertex. The interior angle of an N-gon is (1- 2/N)π radians....	[ "Triangles are sturdy; while a rectangle can collapse into a parallelogram from pressure to one of its points, triangles have a natural strength which supports structures against lateral pressures. A triangle will not change shape unless its sides are bent or extended or broken or if its joints break; in essence, e...
Question from my boy: Are some mammalian tails vestigial, and why haven't they disappeared?	Human tails are vestigial because there's no selective pressure against them. In order for natural selection to act to discard a body part (e.g. a tail or appendix), there has to be some evolutionary reason to do so. If having a vestigial tail significantly decreased an individual's ability to mate or survive, ther...	[ "The coccyx, or tailbone, is the remnant of a lost tail. All mammals have a tail at some point in their development; in humans, it is present for a period of 4 weeks, during stages 14 to 22 of human embryogenesis. This tail is most prominent in human embryos 31–35 days old. The tailbone, located at the end of the s...
why does inhaling steam seem to clear up clogged sinuses?	Think of your mucous as a kind of hydrophilic (strongly attracted to water) slime. If you're sick, suffering from allergies, exposed to irritants, etc... then it can be valuable to move that mucous along faster than it would normally. By inhaling water vapor, you increase the water content of the mucous, and it becomes...	[ "Many people believe that steam inhalation reduces cold symptoms. There is no evidence suggesting that steam inhalation is effective for treating the common cold. There have been reports of children being badly burned by accidentally spilling the water used for steam inhalation.\n", "Breathing low-temperature ste...
maslows hierarchy of needs.	Basically it talks about what a person can focus time and energy on as one tries to be as complete and satisfied a human as possible. The idea is that for example it is hard for someone to worry too much about whether they have an artistic outlet if they are worried about how they are going to find food for the night....	[ "Maslow's hierarchy of needs is a theory in psychology proposed by Abraham Maslow in his 1943 paper \"A Theory of Human Motivation\" in \"Psychological Review\". Maslow subsequently extended the idea to include his observations of humans' innate curiosity. His theories parallel many other theories of human developm...
Why did China recieve Veto-power at the creation of the SC of the UN?	They were 'granted' this at the Conference of Cairo in 1943 by FDR and Churchill. The Americans needed the Chinese to continue the fight against the Japanese on the mainland, since most of the Japanese armed forces were occupied fighting the Chinese United Front (Both the Kwomingtang and the Communists). At Cairo FDR a...	[ "In 1971, the Republic of China was expelled from the United Nations, and the Chinese seat was transferred to the People's Republic of China. China first used the veto on 25 August 1972 to block Bangladesh's admission to the United Nations. From 1971 to 2011, China used its veto sparingly, preferring to abstain rat...
How close could i get to building a modern day jet engine with the materials and techniques used at the time of the Wright brothers' first flight?	It depends on which modern day jet engine you're talking about. A real actual [turbofan](_URL_4_) or [turbojet](_URL_2_) like on a jet airliner, no way. The tolerances for heat and stress just weren't available in 1903. [Turbine Blades are often the limiting part of the engine](_URL_1_) and are generally made form ex...	[ "BULLET::::- The aircraft engine that will power the Wright brothers' first airplane later in 1903 is run for the first time in Dayton, Ohio, United States. It is the first successful attempt to build a heavier-than-air aircraft engine.\n", "The Wright brothers flights in 1903 are recognized by the \"Fédération A...
What number would our number system have to be based on for PI to be equal to 3.2?	If b is the base, then you'd need pi=3+2/b. Solve for b to get b=2/(pi-3). This is closest to 14, and in base 14 pi is 3.1D ish, where D is 13, so it's the base 14 equivalent of 3.19	[ "The spectator's 3-digit number can be written as 100 × A + 10 × B + 1 × C, and its reversal as 100 × C + 10 × B + 1 × A, where 1 ≤ A ≤ 9, 0 ≤ B ≤ 9 and 1 ≤ C ≤ 9. (For convenience, we assume A C; if A C, we first swap A and C.) Their difference is 99 × (A − C). Note that if A − C is 0 or 1, the difference is 0 o...
In this video of the tsunami in Japan there is a white cloud moving out of the water and disappearing. What is it?	You can see it happen at around the [10 min 32 sec mark](_URL_0_) too (just a little bit to the left of the spot in your video, under the tree). Maybe it's a punctured tank of gas, like propane. It's venting gas all the time, it just looks like that when it's above water.	[ "The image depicts an enormous wave threatening three boats off the coast of the town of Kanagawa (the present-day city of Yokohama, Kanagawa Prefecture) while Mount Fuji rises in the background. While sometimes assumed to be a tsunami, the wave is more likely to be a large rogue wave. As in many of the prints in t...
why is it illegal to download movies/music/games/etc, but people can sell used copies? either way the company isn't getting a cut after the first time.	First off, the difference is that a digital copy is endlessly duplicable, while a physical item changes hands -- if you sell a CD, you no longer have access to that CD. But you could copy a music or video file and still have that media while also selling it. Secondly, there are laws that define "first-sale doctrine" -...	[ "A 2009 court case, \"United States v. Dove,\" ruled that the content industry equation of lost sales with illegal downloads is not valid, with the judge noting \"Those who download movies and music for free would not necessarily purchase those movies and music at the full purchase price... although it is true that...
Do we know when certain food and drink pairings first became popular? Eggs and bacon? Wine and cheese? Etc	This question has been removed because it's [an "in your era" or "throughout history" question](_URL_0_), which are not appropriate for this subreddit. If you have a specific question about a historical event or period or person, please feel free to re-compose your question and submit it again.	[ "Although the bacon and egg combination is not unique to any country, its use in modern cooking is notable in New Zealand and Canada. Recipes for it have been found as early as \"The Experienced English Housekeeper\" in 1769.\n", "The Ancient Romans were the first to understand the binding properties of eggs. Dur...
why do pain killers help some types of pain, but not others?	Different kinds of pain killers (analgesics) react in the body in different ways so you need to identify what's causing the pain to effectively treat it. Basically it's a combination of the type of pain (Cancer/Inflammatory/Neuropathic/Nociceptive) and the severity of said pain.	[ "Such action extends the duration of enkephalin effect where the natural pain killers are released physiologically in response to specific potentially painful stimuli, in contrast with administration of narcotics, which floods the entire body and causes many undesirable adverse reactions, including addiction liabil...
Why was Yugoslavia formed after WW1, rather than re-establishing the Kingdom of Serbia?	My first comment here. Hope my answer will suffice! Yes, there was strong local desire for such a state before the First World War. Yugoslavism became a distinguished segment of the wider Pan-Slavic movement around the 17th century. It was popularised by the Illyrian movement in the 19th century and afterwards, throu...	[ "The Kingdom of Yugoslavia was drawn into World War II following the Yugoslav coup d'état of 27 March 1941 and the German-led Axis invasion of Yugoslavia that followed on 6 April 1941. Yugoslavia was quickly defeated and dismembered by the Axis powers, and before the Yugoslavs had even surrendered, the Germans orch...
During the period of westward expansion, were there any U.S. or European leaders arguing against the appropriation of the land or taking up the cause of indigenous peoples?	In the 1832 Supreme Court case Worcester v. Georgia, Chief Justice John Marshall, in the majority opinion, ruled that the Cherokee nation was its own distinct community and not subject to the laws of a particular state. How, Andrew Jackson chose not to enforce that ruling, thus paving the way for the Trail of Tears.	[ "In the case of Public Lands, European colonizers forcibly relocated many Southeastern Native American tribes. One argument against reparations is that in assigning public lands to African-Americans for the enslavement of their ancestors, a greater and further wrong would be committed against the Southeastern Nativ...
how to buy a house, and what "refinancing a mortgage" is or "taking out a second mortgage".	You find a house that you like and make an offer to buy it. With that offer, you include something called "earnest money" that goes directly to the sellers, typically $1000-$2000. This money shows that you are serious about buying the house. If the seller accepts your offer, you will sign a contract to buy with a sp...	[ "When refinancing, if the homeowner wants to refinance the first mortgage and keep the second mortgage, the homeowner has to request a subordination from the second lender to let the new first lender step into the first lien holder position.\n", "A mortgage loan or, simply, mortgage () is used either by purchaser...
when looking at cell phone coverage maps, why is there always a drastic line that cuts vertically across the us?	Population density. Notice the vertical line on [this map.](_URL_0_) It's not cost effective to provide dense coverage where the population isn't also dense. Typically you'll see coverage over major roadways or cities or pockets of population. Coverage resumes on the west coast.	[ "Often coverage maps show general coverage for large regions and therefore any boundary indicated should not be interpreted as a rigid limit. The biggest cause of uncertainty for a coverage map is the quality (mainly sensitivity) of receiving apparatus used. A coverage map may be produced to indicate the area in wh...
why does using cellular data have such a big hit on battery life?	To get more data the radio needs to work harder, which takes more power. The radio is the second largest power consumer in your phone behind the screen, so if you're say streaming netflix you're killing your battery because you're asking the radio to do a ton of work and then using it to watch a movie.	[ "By the end of 2017, smartphone battery life has become generally adequate; however, earlier smartphone battery life was poor due to the weak batteries that could not handle the significant power requirements of the smartphones' computer systems and color screens.\n", "Due mainly to the widespread loss of power, ...
Are there any records of black people in medieval Prussia/Czech Republic? If so, are there any records of how they were treated?	[There you go](_URL_0_)	[ "The poet Adam Mickiewicz retells in his poem \"Dziady\" how the Black Brothers from Kražiai were the first among the Lithuanian youth to be prosecuted in the Russian Empire. In the poem there is also a scene where Mickiewicz describes how the young adolescents, handcuffed and chained, were bid farewell at the Gate...
Folk, Baroque, Classical, Rock & Roll... how much have musical genres varied amongst any one culture throughout history?	I'm only qualified to give a response for european music, so I hope there is someone out there who is learned in asian and african music who can contribute as well. There were definitely different "genres" of music as far back as the late medieval period. The split between sacred music and court music is a perfect exam...	[ "The field of art music, also known as \"classical music\", includes various musical styles such as Renaissance, baroque, classical, romantic, 20th-century music, and post-modern music. Guatemala was one of the first regions of the New World to be exposed to European music. The Spanish missionaries and clergy intro...
why is solar power quite common here in northern england when we have very low solar potential and are one of the windiest places on the planet?	There was a time a few years ago the government has heavily subsidising solar power. The subsidy was so high that if you had a large enough roof you could not only get all your electricity for free but earn money by selling the surplus to the grid. With house prices being very low in the North it was much easier to bu...	[ "In 2014, Imperial College predicted that Britain could have 40% of electricity from solar power in sunny days by 2020 in 10 million homes compared to a half a million homes in start of 2014. If a third of households would generate solar energy it could equal 6% of British total electricity consumption.\n", "The ...
Can the internet be disabled, even temporarily? Does it have a hardware or software vulnerability that would shut it down everywhere?	The only method I am loosely aware of to kill/shutoff the internet is if a major AS like AT & T or Level 3 were to go rogue and start advertising routes for basically every IP address and send them more or less nowhere. I wish I could tell you that I am a network engineer and I understand this in depth, but I don't. Y...	[ "Policy makers have to take into account the cost of shutting down the Internet, if it is even possible. The loss of the network for even a day could cost billions of dollars in lost revenue. The National Cybersecurity Center was set up to deal with these questions, to research threats and design and recommend prop...
if you punched someone hard enough to knock them out whilst they were sleeping, would they wake up and pass out or stay asleep through your punch?	Typically if you hit someone hard enough to knock them out, it’s caused some degree of brain damage. Even if very mild, you definitely gave them a concussion. I’d wager they go into a sort of deeper sleep from their brain being jarred. Unconsciousness in that way is different from sleep.	[ "Knocking a person unconscious or even causing a concussion may cause permanent brain damage. There is no clear division between the force required to knock a person out and the force likely to kill a person. From 1980 to 2007, more than 200 amateur boxers, professional boxers and Toughman fighters died due to ring...
the texas bill about wrongful births.	In Texas (and maybe other states, I'm not sure) a mother can sue a doctor for failing to properly diagnose problems with a fetus. This started in a 1975 case where a pregnant woman sued her doctor. She got rubella while pregnant and claimed her doctor failed to properly diagnose her or warn her about the effect the ill...	[ "Texas has the seventh highest birth rate in the United States, with nearly 400,000 babies born each year. Over half of all Texas births are paid by Medicaid, totaling over $2.2 billion per year in birth and delivery-related services for mothers and infants. Studies have found that infant mortality is usually cause...
can dreams actually tell us something or are they just random head-noise	Don't listen to some of the ignorant comments here. The only truth we know about dreams is that we don't really know what their exact purpose is. There are many interesting theories about it, but the true purpose of dreaming is not yet understood. That being said, you can definitely choose to find meaning behind your ...	[ "John Allan Hobson and Robert McCarley propose that dreams are caused by the random firing of neurons in the cerebral cortex during the REM period. Neatly, this theory helps explain the irrationality of the mind during REM periods, as, according to this theory, the forebrain then creates a story in an attempt to re...
how do lice see?	They see with their eyes. Umm... I'm not sure what you really expected. They usually have two little eyes on their head which they use to look around, but they may also just navigate from the dead, cold bird towards the warm flesh of the girl who just picked it up.	[ "Lice can be indicators of contact with another person. Many species closely associated with humans can be easily transferred between individuals. DNA identification of multiple individuals using blood meals from body and head lice has been demonstrated in laboratory settings.\n", "PEX is characterized by tiny mi...
- what is a solar/steller wind?	Ok Most stars are basically giant fusion reactor which constantly spits out radiation and charged particles, And think there are trillions of them around the galaxy and universe doing that exactly, depending on the type of star they spit out different ranges of radiation and at different strength, those radiations...	[ "The solar wind is a continuous stream of plasma that flows outwards from the Sun: near the Earth's orbit, it contains several million protons and electrons per cubic meter and flows at . The magnetic sail introduces a magnetic field into this plasma flow which can deflect the particles from their original trajecto...
why does our brain stop us from biting down too hard on a finger, but will allow us to willingly kill ourselves?	The brain does not allow us to willingly kill ourselves, on an instinctive level. If you jump headfirst out of a window, you'll be forced to try to save yourself during the fall. You will raise your arms to try and break the fall. This is analogous to preventing us from biting our fingers off. However, both can be ove...	[ "Giving the finger has resulted in negative consequences. A Malaysian man was bludgeoned to death after giving the finger to a motorist following a car chase. A Pakistani man was deported by the United Arab Emirates for the gesture, which violates indecency codes.\n", "Nail biting usually leads to harmful effects...
Do we have the technology to "rewrite" someone's DNA?	Allow me to parse your question into a few different ones (I'm going to interpret "rewrite" loosely, to include getting a cell or cells to express a single new gene. More complicated "rewrites" are possible using similar techniques, but may be disproportionately more complicated to carry out.): > Do we have the tech...	[ "Baltimore recently joined with other scientists to call for a worldwide moratorium on use of a new genome-editing technique to alter inheritable human DNA. A key step enabling researchers to slice up any DNA sequence they choose was developed by Emmanuelle Charpentier, then at Umea University in Sweden, and Jennif...
military redditors: what is the point of announcing ahead of time where and when we will be mounting an attack against isis? doesn't this just help the other side prepare a defense?	The warning is given so that civilians have an opportunity to get out of the area. This type of warning is given in this situation because, even if they have all of the time in the world to prepare a defense, they can not win. If this were a war between equals, or an existential war, warning would not be given.	[ "On 4 November 2016, Fox News reported that the U.S. military ended its bombing campaign against ISIS in Sirte after three months of round-the-clock airstrikes the U.S. military conducted a total of 367 airstrikes since 1 August 2016, according to officials, no American airstrikes took place since 31 October; units...
Can we learn things while we sleep?	It is pretty unlikely that you have the capability to learn while sleeping like that. It has been theorized that your brain spends your time sleeping to unpack the information from the day and store it, so it may not be able to learn additional information because it is already at capacity. However, this is a subject ...	[ "Since the electroencephalography studies by Charles W. Simon and William H. Emmons in 1956, learning by sleep has not been taken seriously. The researchers concluded that learning during sleep was \"impractical and probably impossible\". They reported that stimulus material presented during sleep was not recalled ...
why do i get shivers when i take a shot of cheap whiskey?	Please tell me you are not doing shots with single malt scotch? Cheaper blended whiskys are mixed with grain alcohol (basically vodka), more expensive whisky will be just made with malt barley and pure spring water	[ "BULLET::::- Stage 1 (30 minutes to 12 hours) consists of neurological and gastrointestinal symptoms and looks similar to alcohol poisoning. Poisoned individuals may appear to be intoxicated, dizzy, lacking coordination of muscle movements, drooling, depressed, and have slurred speech, seizuring, abnormal eye movem...
why is judge an elected position?	Perhaps not the answer you're looking for, but electing judges (and a few other legal professions, such as district attorney) is an almost uniquely American habit. Much of the rest of the world (certainly that which is based on the British legal system) performs judicial appointments via the legislature or executive, o...	[ "The court's judges are appointed solely by the Chief Justice of the United States without confirmation or oversight by the U.S. Congress. This gives the chief justice the ability to appoint like-minded judges and create a court without diversity. \"The judges are hand-picked by someone who, through his votes on th...
What would a battle during World War II really be like? Do any video games actually simulate this?	I think one thing which many downplay was just how static the soldier's experience of WWII could be. It was not all, or even mostly, aggressive attack and counterattack like popular culture implies. German offensive successes in 1940-42 (what most people call Blitzkrieg, although the Germans never called it that) and t...	[ "For many World War II wargamers, this became the ultimate World War II wargame, even if it was not possible to complete all that many games. Nearly two decades later, Decision Games published a computer version by Greg Ploussios which recreated the game, which is still played by email between enthusiasts. The main...
When and why Viet Nam and Korea (both North and South) abandoned Chinese characters?	North Korea made the shift starting in the late 1940s. 1949, officially. South Korea was still using them quite frequently as late as the 1990s, and you can still find plenty of examples of mixed script Korean in academic texts today. In the early 90's newspapers finally switched over to Hangeul. However Chinese chara...	[ "Produced five years before the beginning of the United States' rapproachment with Mao Zedong in 1972, \"Red Chinese Battle Plan\" was made during the Vietnam War under the Lyndon Johnson administration. Despite the widening rift between the China and the Soviet Union, both powers supported the Vietnamese communist...
why would the government classify alien activity ?	It is almost guaranteed that evidence of extraterrestrial life would destabilize the planet. We've seen how people behave at a Walmart on Black Friday - How would they act if they found out there was a superior species out there? Fear, hope, riots, gatherings would occur. Everything you know and love about your so...	[ "Alienage, or the state of being an alien, i.e. a non-citizen of the United States, is a unique category. For purposes of state law, legal aliens are a suspect class (\"Graham v. Richardson\", 403 U.S. 365 (1971)). As such, state actions are analyzed according to strict scrutiny. In contrast, because the United Sta...

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