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1ph8pm | why do dry counties still exist in the u.s.? | I'm confused as to what real purpose they serve. I assume most people just go into the next county to get alcohol, so from a business point of viewwhy would you want to pass up on that revenue? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ph8pm/eli5_why_do_dry_counties_still_exist_in_the_us/ | {
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"Because religion. Because politics. Because they dont want some store getting all the town yahoos tanked up n hangin all around town causing ruccus!",
"Some people believe the moral or societal cost of permitting alcohol sales in their county outweighs its prospective benefit. It's really as simple as that. People object to it on moral grounds, or on the basis they believe it will contribute to crime, poverty, etc.\n\nSource: I was born and bred in a dry county; there were maybe 3 places (all private clubs) you could go for a drink, and absolutely no liquor stores. The local churches had a stranglehold on the city council and the liquor licenses they issued, and nothing budged until relatively recently. Now serving liquor is permitted (subject to rather rigorous licensing requirements and a substantial excise tax), but there are still no liquor stores.",
"Because the citizens of the county don't elect leaders to change the law (or the citizens are happy with the way the current law stands). Perhaps they feel there would be too many problems attached with that revenue or they don't feel the law inconvenences them excessively. After prohibition ended local laws set their own rules, and people are allowed to choose locations that provide them with the most benefit. ",
"They tend to exist in *poor*, *rural* counties. In these places, there was a high correlation between domestic violence, vehicle accidents, alcoholism and availability of alcohol. Cities differ because they have public transportation and nosey neighbors with local PD on speed-dial. \n\nThe theory is \"dry counties\" protect families and save lives. These counties tend to be economically dead and full of old religious folks. Even if they overturn the local law - no liquorstore or bar would open up because there's never been a market for it.",
"I also think that with the added mobility and improvement in roads after WWII that anyone in a dry country that wants alcohol can get it. Either from the local private club (a lot of VFWs halls that sprung up after WWII do this) or from driving over the county line and bringing it back. This is a good reason for almost all laws having a sunset clause in them so they have to be renewed or they automatically go away."
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3i2g8s | why are bright white led lights allowed on cars for use at night when white light reduces your ability to see in the dark? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3i2g8s/eli5_why_are_bright_white_led_lights_allowed_on/ | {
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"We normally drive with our headlights set to a \"dipped\" position. This means that they are pointed down slightly, so you can see the road ahead of you, but the lights don't point directly at oncoming drivers and blind them.\n\nYour car will have a \"main beam\" setting which can be used on unlit roads when there is no one coming towards you, which *does* blind oncoming drivers like you've described. There's usually a warning light (blue, by convention) on the dashboard to warn you you're using this light, so you don't forget to turn it off.",
"It's because of regulatory lag and lobbying. Almost like e cigarettes. The regulations did not anticipate these lights being feasible and so did not regulate them. By the time it because apparent these lights and HID lights are a problem, too many vehicles have been fitted with them to retrospectively impose regulation. ",
"Hm lots of misinformation here. First, the DOT doesn't approve headlights. There are SAE tests for legal headlights. If your product passes the tests, it is DOT compliant and can have the lettering on it. As far as LED headlights, they're just vastly superior. AAA just put out a study which showed you could see almost 20% further with LED headlights. The color temperature that you speak of is also much better. Usually around 5200K, which is about the color of daylight. They last longer, typically 30,000 hours on low beam while halogens will last about 3,000 hours, and they are durable as hell. If you are seeing glare from an LED headlight, they are either not DOT compliant or they haven't been aimed properly. All headlights should be aimed. \n\nSource: work for a headlight company ",
"They are illegal in a lot of places to install improper hid kits, without the cutoffs. My hids project a beam like this: _/- from each light, which does not blind drivers unless I have my high beams on (which would always blind drivers) "
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8t2pfx | What led to the drastic differences between Art Deco and Art Nouveau, especially since they were so close together chronologically? | They were only 10 years apart, and yet their styles are so very different!
Side note: I would love for there to be an Art Nouveau revival. Its by far my favorite movement of art! | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8t2pfx/what_led_to_the_drastic_differences_between_art/ | {
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"\n*Note: I wrote this in reply to a follow-up question on connections between Art Nouveau and colonialism that was deleted since, so I'm putting it here since I don't know where else. Can delete it if that's not fine. (pinging u/amusiclistener and u/JosephvonEichendorff from that discussion)*\n\nInteresting question - it made me think of Belgian art nouveau and its connections to the Belgian Congo. When I was living in Brussels I noticed quite a few statues relating to Belgian colonialism, but also references to Congo in Art Nouveau - for example African objects statues of African people and on Art Nouveau house facades. Looking a bit into it, there's a very interesting 3-part article on this topic: \"Art Nouveau, Art of Darkness: African Lineages of Belgian Modernism\" by Deborah Silverman. The first part deals more with the historical background, arguing that\n\n > Decorative arts and architecture, then—the visibly bolted and conspicuous\ngaps on the bodies of the Congo ivories and the spatial designs of coup de fouet—\nsuggest that stylistic forms of modernism in Belgium expressed a displaced\nencounter with a distant, but encroaching, imperial violence—the return of\nthe repressor in visual form. [170]\n\nMore concretely Silverman describes the beginnings of Belgian colonialism, with Leopold III's personal possession and exploitation of Congo fueling the Belgian economy and technological advances. This also influenced Leopold's image as builder & architect, with the resources coming in from overseas influencing a building boom in Brussels and elsewhere. Finally, this also influenced important artists/designers/architects like Voctor Horta and Van de Velde, instrumental in develoing the art movement there during the early 20th century. Patrons rich through African trade also financed the blossoming Art Nouveau buildings and art. \n\nSilverman also convincly (I think) argues how materials but also styles from Africa influence Belgian Art Nouveau - examples include materials like ivory and woods; but also traditional art and forms. A large number of African art objects (among other things) were brought to the later royal museum at Tervuren where they went on public display to large audiences; and expositions of Art Noueveau artists using ivory and showing an image of a sphynx for example. The article has many interesting images and examples on this, so I would rather recommend it than going into more detail here (part 1 [can be found here](_URL_0_)). Finally, Belgian Art Nouveau may not be as well known as e.g. French or Austrian styles, but it seems to have been quite influential on those. It developed early on, and someone like Horta was certrainly revolutionary in his use of new materials like steel and his focus on light in his architecture. Later on you of course also have more influence from those other countries going back to Belgium. This got a bit longer, so I'll close with another quote from the article, summing up some of its main points:\n\n > Bold experiments in artistic synthesis flourished in the Belgian art nouveau movement that sought a new unity of art and craft,\narchitecture and design, liberated from history and tradition. The unprecedented\neconomic prosperity and overseas expansionism of fin-de-siècle Belgium\nprovided progressive artists such as Victor Horta, Henry van de Velde, and Paul\nHankar with elite patrons and some budgets awash in Congo dividends. But\nthese artists’ creative consciousnesses were also vitalized by the sudden and\nsuccessful Congo venture, and they shared the exhilaration of their contemporaries,\nas well as some of the collective derangement, over the fact that their\nsmall, new, and neutral nation had “acquired” one-thirteenth of the African\ncontinent and had been summoned as the headquarters of what the first museum\ndirector called in 1910 an “invasive civilizationism” powered by financial\ncombines, railroad tracks, and grateful natives. [143-44]",
"The real issue here is how we (and I include myself in this, because my answer on 1890s nostalgia the other day did it) discuss late-late nineteenth century and early twentieth century decorative arts as Art Nouveau, as a block, and then we say that Art Deco happened after it. In reality, we can look at Art Nouveau and what would come to be called Art Deco after the 1925 *Exposition internationale des arts decoratifs* as two intersecting branches descending from the styles that came before them.\n\nLet's start with the Arts & Crafts movement, most popularly associated with William Morris. (Here's one of his most famous textile designs - \"[The Strawberry Thief](_URL_0_)\".) This style was, to a great extent, a counter-cultural reaction against industrialism and a perceived decline in artistry and craftsmanship in the face of cheap, mechanized manufacturing. As a result, Arts & Crafts work took a lot of inspiration from the late Middle Ages: look at \"Strawberry Thief\"'s *millefleurs* background with densely-packed plants, and compare it to that of \"[The Unicorn in Captivity](_URL_3_)\", ca. 1500. You can also see it in [Morris's house](_URL_4_), which resembles buildings from around 1500 as well. While the style began flourishing in Britain, it soon became international, with American artists like [Candace Wheeler](_URL_6_) taking it on and making it their own. There's also a subtle influence from Japanese architecture and decorative arts, which would continue through the later decades and become more explicit.\n\nArts & Crafts contained the seeds of *both* Art Nouveau and Art Deco, and during the time that it was developing into both of them there was not a clear line drawn between the different movements. The progression to Art Nouveau involved an exaggeration of the curved lines that were already present in many aspects of Arts & Crafts - you can see the slight curves in \"[Kennet](_URL_1_)\" from 1881, and \"[Cray](_URL_7_)\" from 1884, associated with naturalistic floral stems. Organic curves like these would be added to all types of forms in textiles/on paper and to furniture, and by 1891 the Arts & Crafts label could cover a desk like [this](_URL_8_), which we would now unequivocally call Art Nouveau. Although this style could be found throughout Europe and America, it was particularly associated with and popular in France.\n\nSome Arts & Crafts instead evolved in a *less* florid way, creating a proto-Art Deco years before the label was invented. Charles Rennie Mackintosh is the perfect example: [this illustration](_URL_2_) from 1896 uses slightly abstracted forms and lots of long vertical lines that you wouldn't expect so early, and [this one](_URL_9_) of around the same time incorporates that Art Nouveau sinuousness with the abstraction and vertical lines, all of it involving a lot of fine, \"unnecessary\" detail which would disappear from the scene by the time of Art Deco. The Craftsman style, which is essentially what American Arts & Crafts is called, tended to eschew the curves and fine detail fairly early, and as a result has an almost timeless look - the work of [Gustav Stickley](_URL_5_), for instance, or [Frank Lloyd Wright](_URL_10_) (to a lesser degree - Wright's doesn't look timeless, but it doesn't look turn-of-the-century, either). The Austrian *Wiener Werkstatte* (Vienna Workshop) likewise started at the turn of the century with Arts & Crafts principles and used a very pared-down, \"modern\" aesthetic. All of this was somewhat avant-garde and not commonly available to the average person, or used in a lot of everyday pop culture - like advertisements or sheet music covers - which is why people don't think of it existing during this period. As the popular influence of Art Nouveau waned, aided by a resurgence of interest in the simplified Neoclassical, these avant-garde styles trickled down to the middle and working classes while they continued to develop into what is known as Art Deco."
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1owvl1 | Why are the Planck Units calculated using G, h and c, why are these called "fundamental" constants and why do they show up the limits of applicability of our physical theories? | askscience | http://www.reddit.com/r/askscience/comments/1owvl1/why_are_the_planck_units_calculated_using_g_h_and/ | {
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" > Why are the Planck Units calculated using G, h and c, why are these called \"fundamental\" constants and why do they show up the limits of applicability of our physical theories?\n\nFundamental because they're arbitrary. They're not tied to no planet's circumference, no platinum block's mass, no 9*10^9 oscillations between some atom's quantum state. They're natural, or by nature. If some intelligent life out there knew of maths, they'd probably use some variation of their planck units also. ",
"There's a redundant set of fundamental constants. Some can be defined in terms of other ones or vice versa, but nobody really knows which ones are 'more fundamental'. \n\nPlanck units one of a number of sets of [natural units](_URL_0_). You change the units of your problem so the constants equal 1 and it simplifies the math to not have to keep writing those constants everywhere. \n\nThis has been answered many times (I think it's in the faq?) but Planck units do _not_ actually have any _known_ physical significance in themselves. They're merely an order-of-magnitude estimate of _around_ where quantum and gravitational effects should be on the same scale, and where our current theories shouldn't work, because we don't have a quantum theory of gravity. But we've not been able to observe that. \n"
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75aiy4 | how does the earth (and everything else) just float, suspended in space? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/75aiy4/eli5_how_does_the_earth_and_everything_else_just/ | {
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"We don't just float. We are travelling very quickly around the sun. We don't just sit suspended in space.",
"The short answer is: it doesn't. We are constantly falling towards the sun. It's just that we're also moving sideways at the same time so that we never actually hit the sun, but keep going around it. The sun (and all the planets around it) are also falling, towards the middle of the Milky Way. But again, because the sun and planets are moving sideways relative to the center of the Milky Way, we keep going in circles around the center.\n\nIn the end everything is rotating around other stuff. There is no real up and down to fall to. We just keep falling towards other massive objects. ",
"It isn't. Earth is constantly being pulled toward the sun. But since it has a high tangential velocity (ie. it is travelling in a directly that would otherwise make it fly by the sun), the pull ends up making the planet orbit in an elliptical pattern. This applies to every planet in the solar system as well as every moon around those planets. And also extends the other way to solar systems orbiting a galaxy. They are all moving yet held in orbit by gravity. Celestial bodies that moved faster didn't stay in orbit, and bodies that moved too slowly were pulled into the larger bodies."
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3voxvz | i don't understand how something sealed in the freezer gets more and more ice in there after months/years. where is the water coming from exactly? | I put a box of individually wrapped egg rolls from Costco in my freezer a year ago. I've eaten them slowly and it's still half full of wontony goodness.
I've noticed that when they were new, there was no ice in the little packages. Then more, and more and more. Today I opened a few and my plate was so full of ice I had to wipe it off before cooking them. I would estimate 4 egg rolls had 2 TBSP of ice in there!
Where is this water / ice coming from?? The egg rolls appear to be exactly the same as new. They're not dried out freezer burned junk. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3voxvz/eli5_i_dont_understand_how_something_sealed_in/ | {
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"Every time you open the freezer door a little warm air gets in there and the moisture in the air cools and condenses sticks to everything. It's too small an amount to notice from 1 opening of the door to another, but it is noticeable after hundreds/thousands.",
"From inside the food. It's called freezer burn. Even if you seal it in a bag every time you open up the door and close it part of it begins to thaw. When it refreezes the water expands forcing itself to the surface of the food."
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tv7eq | Do zoos have a problem with some of their more intelligent animals committing suicide? | Maybe I'm just anthropomorphizing, but I've noticed some animals, especially the more intelligent ones (apes, monkeys, elephants, etc.) don't look particularly happy with their lot in life. Have their been cases of zoo animals intentionally killing themselves?
More generally, do animals in the wild ever commit suicide? | askscience | http://www.reddit.com/r/askscience/comments/tv7eq/do_zoos_have_a_problem_with_some_of_their_more/ | {
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"No. \n\nAnimal suicide is almost never observed outside of a few fish species and humans. In zoos, I don't think it has ever been observed. If someone who works in zoos or with animals can contradict me, I welcome the correction.",
"People say cetaceans are voluntary breathers, and they need artificial means for respiration under anesthesia or else they don't breathe. Because of this and their intelligence, some may argue that they do commit suicide by choosing not to breathe.\n\n[I was going to argue this point but it turns out to be misinformation](_URL_0_), and they are involuntary breathers. We just don't understand anesthesia in marine mammals very well. ",
"I think they just degenerate into a state of catatonia or mental illness.\n\nI'll never forget at about 12 years old seeing a polar bear in a tiny cell in Sea World standing on a 'rock', diving into the pool for a 3 second swim, climbing back out onto the 'rock' and repeating the pattern. I stood there watching him for about 10 minutes, and it saddened me to think that he'd probably been doing that for months, if not years, before i happened to be there to witness that majestic creature reduced to a horrifying spectacle."
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2n6x8w | How did the British manage to turn all the German spies in WWII? And how were they so successful at feeding false information? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2n6x8w/how_did_the_british_manage_to_turn_all_the_german/ | {
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"Once the British/Polish/French/allies had broken Enigma they knew of every single spy that landed in the UK. This allowed them to 'meet' them as they landed. The entire operation was called Operation Double Cross and was probably the most successful counterintelligence operations ever undertaken. There were 138 German spies sent to the UK and of them 40 (ish) were successfully recruited by the British as double agents. Most were taken to Camp 020 where they were given a choice: be a double agent or die. However, not all of them were executed, only those deemed useful and who refused. The rest were imprisoned. \n\nThere are a number of reasons why it was successful: Canaris had previously been prohibited from sending agents in to the UK but as soon as Operation Sea Lion was developed Hitler wanted a maximum effort put in to espionage in the UK. This left Canaris with little choice but to recruit from wherever he could. A lot of the agents were not necessarily loyal to Germany and definitely not to Hitler. Many were profiteers, adventurers, etc. None of them had much more than a basic course in espionage. \n\nSo, you have a bunch of people with little to no experience, and little to no loyalties, who are met at their landing points by people who knew everything about them (code names, objectives, etc), and who were skilled in turning agents. They were offered money and relative safety and all they had to do (simplified of course) was transmit cooked information to the Germans. Seems like a pretty good deal!\n\nOne of the most famous of these agents was TATE. He was the most successful of the German double agents and spent the war sending cooked information. The Germans thought he was a valuable asset and had no idea what was going on. Getting TATE turned also helped with learning the landing points of newer spies being flown in as most of them went through him seeing as Germany believed they had a solid spy ring sitting in the UK. Other agents included: BRUTUS (Polish), TREASURE (a French woman who was probably in it for the adventure), GARBO (Spanish entrepreneur), and TRICYCLE (Ukranian). \n\nIt really was a brilliant course of action but it could not have been done so successfully had it not been for a few blunders on the part of the Germans (to be honest, the Abwehr, for all of their work, were pretty keystone cop when it came to espionage): lax training, not being picky about who they sent over to spy for them, and, of course, their refusal to even entertain the idea that anyone could break Enigma. That really was their downfall. On the other side we have the skill of the British at turning agents, the promise of safety and a pretty good life considering that these turned spies were given well above and beyond basic UK rations and were wined and dined to keep them keen.\n\nSources and further reading:\n\nCrowdy, T (2011) Deceiving Hitler: Double Cross and Deception in World War II \n\nJonason, T. and Olsson, S., (2012) Agent TATE: The Wartime Story of Harry Williamson\n\nMacIntyre, B. (2012) Double Cross: The True Story of the D-Day Spies\n\nMcKay, S. (2010) The Secret Lives of Codebreakers: The Men and Women Who Cracked the Enigma Code at Bletchley Park\n\nShulsky, A (2002), Silent Warfare: Understanding the World of Intelligence\n\nTalty, S. (2012) Agent Garbo: The Brilliant, Eccentric Secret Agent Who Tricked Hitler and Saved D-Day\n\nVolkman, E., (1996) Espionage: The Greatest Spy Operations of the Twentieth Century.\n\nVolkman, E., (1994) Spies: The Secret Agents Who Changed the Course of History\n\n\n"
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7fr863 | why do we get vibration-like echoes when driving and we open the rear windows? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7fr863/eli5_why_do_we_get_vibrationlike_echoes_when/ | {
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"My best guess is that it has to do with airflow not being consistent. I notice this the most when only one window is rolled down and it seems to stop if I open another window on the other side of the car. I think it’s because the air is rushing in and out of the same window, causing alternating high and low pressure in the car. \n\nOr is it the same phenomenon as a wind instrument and the pulsing is just a really low frequency note that is created?"
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4h7sg0 | what are the little white table-looking things they put in the middle of take-out pizzas? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4h7sg0/eli5_what_are_the_little_white_tablelooking/ | {
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"Those are props, or spacers, to keep the middle of the pizza box lid from collapsing and getting smooshed down on to your pizza.",
"They are to keep the top of the box from collapsing into the pizza, getting cheese all over the top, and ruining the pizza; it is like a support column to hold up the roof.",
"Its to hold the top of the box up so it does not collapse and fall into the pizza. Most pizza places I go to dont use them though. probably a question for r/askreddit ",
"They are there to keep the top of the box from pressing down into the top of your hot pizza. \n\nAlso..they are tables for doll houses."
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6gmwhb | in british politics, what are the politicians with 'shadow' in their title e.g shadow chancellor, shadow foreign secretary. what is their purpose? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6gmwhb/eli5_in_british_politics_what_are_the_politicians/ | {
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"They are the official opposition, so the government will have a health minister, the opposition will have someone who \"shadows\" that minister and in debates etc. asks questions and generally holds that minister to account for decisions that they make.",
"Britain has traditionally a two party system. Either Tories or Labour form the government. The other party builds the opposition. The oppositon party also has a kind of ''government''. Like in the real government they have ministers for all the different offices, called shadow cabinet. If after elections, the party who governs changes, often the memebers of the shadow cabinet will become part of the new government.\n\n_URL_0_",
"In a roughly two party system, one party gets the most MPs and forms the Government, with a number of them appointed as Ministers to head the various departments.\n\nThe minority party is in opposition, whose primary purpose is to hold the Goverment to account for it's actions. One way of doing that is to have a \"shadow\" for each minister who has a particular job to keep an eye on that department's actions.\n\nWhen a Minister introduces a proposed law bill to Parliament, the Shadow Minister will lead the \"against\" side of the debate.",
"I am 5 and I have been explained, thanks guys"
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15wc52 | In WW2 did soldiers change sides on the Eastern Front at all? | I remember once reading in a school textbook that when stationed on the Eastern front some Nazi soldiers would become exposed to Soviet propaganda and become convinced that that should support communism. how common was this and how did Nazi commanders deal with it. Similarly did USSR soldiers become Nazis ever and how did the USSR deal with them? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/15wc52/in_ww2_did_soldiers_change_sides_on_the_eastern/ | {
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"I do not know of German soldiers going over to the Russian side, but I do know of Russian soldiers going over to the German side.\nThe SS recruited, at one point, troops from POW camps, English troops, who then fought on the Eastern front. There was about sixty of these troops that switched over, and were called [British Free Corps](_URL_0_). They served on the Eastern front as to not fight their own countrymen.\n\nAt the Battle of Stalingrad, there were 40,000 Soviet volunteers (called HIWIs) fighting for Germany. They remained fighting well into the seige, not out of loyalty to the Germans, but of fear that, if they were captured by the advancing Soviets, they would be tried and killed for treason against the Soviet Union. Around 1/4th of the Sixth armys entire fighting force was made up of such troops. (Beevor, *Stalingrad* 1999).\n\nThe Soviets mainly used German POW's for hard labor for the war effort.\n\nNot being able to do much more research on the matter, considering I'm in school, but I'm guessing the HIWIs were very widespread in the German Army as to support the ever dwindling numbers of German troops.\n\nEdit: Spelling and grammar.",
"A small number of German soldiers/officers did defect to the Soviets under captivity, Field Marshal Von Paulus, the German commander at Stalingrad, is one such example. The Soviets used them to form a \"National committee for a free Germany\" as a propaganda tool. Paulus himself became a firm Communist and many of the officers who joined the committee would go on to have government postings in East Germany.\n\n_URL_1_\n\nThe Nazis, despite ideological reasons, eventually recruited a large number of Soviet citizens and ex-soldiers. The HIWIs are already mentioned. But there was also the Russian Liberation Army headed by Andrey Vlasov, a defected Soviet general. The goal of said army was to liberate Russia from Communism with German help and sought to fight as independent units, and its soldiers recruited from German POW camps. Due to Nazi ideology however, the army was not formed until September 1944, and the RLA only participated in combat at the very end of the war. Interestingly enough as the Third Reich collapsed the RLA turned against the Germans and helped the Czech partisans liberate Prague.\n\nAfter the war many of the RLA soldiers who tried to surrender to the west were extradited to the Soviet Union, Vlasov was executed for treason, and many of the rank and file were sentenced to harsh labour in the gulags.\n\n_URL_0_",
"Soviet soldiers switching to Germany - Was very common on the Ost front. Especially from 41 to about 43 (around Stalingrad's fall), and I am taking only about the ethnic Russians. Soldiers of different ethnicities such as the Ukranians, or the Don Cossacks initially atleast switched sides in reasonably large numbers, the logic was that they saw the Germans as liberators and Stalin / Soviets as oppressors. This was ended almost within the first 3-4 months of the invasion when they realised that the Germans were just as brutal. Switching however continued but maybe not so freely, but with an element of coercing by the Nazi's - induced switching using say food in POW camps. \n\nHIWI's started out as more or less slave labour, but as the war progress, and especially when the Stalingrad Kessel was formed the Germans gave the whole genealogical crap the go by and started using HIWI's as frontline soldiers. Beevor in his book Stalingrad points out that, around this time (Dec 42), the number of HIWI's mentioned on ration rolls started dropping alarmingly, and he postulated that this could be because (A) They are indeed dying at a rapid rate or equally probably (B) They were being shown under dead German soldiers, and not as HIWI's - this was to ensure the rations kept flowing through.\n\nYou also have the case of Vlasov and his army, so as you can see this was fairly common.\n\nHow did the Soviets deal with it? Draconian measures! Beevor in his book gives numerous examples of field leaders being executed because some of their men changed sides. He gives an example of a young lieutenant who had taken command of a squad only 10 days prior to his execution...reason for his execution? 3 of his squad members deserted....\n\nLet alone \"traitors\", even POW's were considered \"former Russians\" (NKVD terminology), Stalin disowned his own son who was captured by the Germans... so yes, the measures taken to deal with traitors or even potential traitors was extreme.\n\nWehrmacht soldiers switching to Soviet side? Happened - but not in the same numbers as Sov's switching to the German side, one of the primary reasons for this is the constant propoganda they were fed that even surrendering Germans were butchered (the same propoganda the sov's fed, and which kicked in around late 42- this is my speculation)...so even when the situation was hopeless, they continued to stick to their kamraden and not switch sides (it was nothing to do with Hitler or any Nazi principle, though the average german GI had a lot of faith in Hitler). There were the few recorded instances which were driven by ideology. In the book, \"War without Garlands\" the author references a communist German soldier who switched sides just before the invasion, but when he reached Sov lines, he was quite simply shot as the Soviets suspected he was a British spy spreading rumours and causing a war with the Germans.\n\ntl;dr - Both sides changed...sides, the Sov's had massive numbers switching sides in the early stages of the war which considerably dropped as they started gaining on the Germans. The Germans switched sides, but in very less numbers. Both sides dealt with it in as draconian a way as possible.\n\nps...Soviet propaganda was more of pysch warfare which used turncoat German soldiers to sing sad German songs, or write pamphlets warning they were going to die away from home and family (apparently, these worked the best), it WAS NOT however speakers blasting the merits of marxism and communism.\n\nAny HIWI returned to Soviet Russia after the war was either executed out of hand or sent straight to the Gulags...so no, the Sov state did not forgive a turncoat...even after the war was over. This was applied to POW's released from German camps as well.\n\nGerman Infantryman (2) Eastern Front 1941-43 by David Westwood talks a little about this aspect, and so does Beevor's Stalingrad...\n\na little offtopic : You also had Kyougjong Yandg - the ultimate side switcher. A Korean captured by the Japanese, he fought for the Japanese, captured by the Soviets in Khalakin Gol, he fought for the Soviets till he was captured by the Germans in Kharkov, and finally captured by the allies during Operation Normandy....so yeah, the ultimate side switcher. "
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6wtpgu | given that we started at $0 and we are now at countless zillions, where did all the worlds money come from? | I'm not talking about paper money, more how can we start with cave men of zero wealth to have built economies worth trillions. I'm assuming people will reply with two people trading with one another however how can either side get back more than what they started with? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6wtpgu/eli5_given_that_we_started_at_0_and_we_are_now_at/ | {
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"You're making the assumption that there was zero wealth to start off. If I'm a caveman and I pick up a shiny rock that other cavemen want, I now have wealth. Likewise if I make a tool out of wood and stone, others might want that tool and not necessarily want to take the time or have the expertise to make their own, so I have a thing to trade.\n\nSo now we have simple trading. I make tools, you farm food. I exchange some of my tools for your food. We both trade with the family that makes clothes. But this becomes unmanageable as you have more items for trade. How many X and you receive for Y when you have hundreds of options for both is just impractical. And when you have seasonal things, there may be times you have too much and others that you have not enough to trade with. Or things that simply can't be broken down for small trades such as if I raised oxen and want a simple tool that isn't really worth an ox.\n\nFrom here, civilization invented currency. Some common trading thing that could be easily quantized, carried, and traded for all other things. It had to be something relatively rare and have enough intrinsic value that others accepted it for trading. Things like shells, beads, and eventually metal coins have all been used by different civilizations. It's only extremely recently that civilization has moved beyond the necessity for currency to have intrinsic value.",
"Money appeared because barter sucks as a means of exchange. You need to have what the other person wants, and even if you do happen to have that, it's often in some hard to transport form (like a cow) or hard to divide up. So people came up with the idea of money to represent wealth. So where did the wealth come from? Someone had to first produce it. They needed something that was rare, portable, divisible and hard to duplicate. Gold served all those purposes, so at least in the old world gold and silver coins became a unit of exchange. Usually rulers made a monopoly on them - but since they couldn't produce gold from nothing, it limited the money supply. \n\nHumans tend to want more money, especially rulers. So they found ways of diluting coins, of shaving them, of counterfeiting them. Some countries experimented with cheap metal or even paper. Mostly these experiments failed, causing inflation. Eventually, long distance traders came up with the idea of promissary notes to take with them while trading, and banking was born. That allowed the money supply to grow dramatically - because the bank could lend money out to someone, who had the money, as well as keeping it for the person who deposited it in the first place. As long as not many people asked for their money back at once, everybody became richer - especially the bank. \n\nToday, money isn't linked to gold at all. Instead, it's given value based on what people believe it is. That's called fiat currency, and it means that the US dollar is worth what it is because people believe it's worth something. If the USA was to suffer a major disaster, a Civil War, or a government collapse, the dollar could become worthless overnight - as a few countries have found, much to their horror. But overall the system works! And it means that the money supply can be increased simply by printing money. Thus, there's more money in the world today than last year, and there will be more next year than this. ",
"Ogg is a good hunter and kills a deer, more than he can possibly eat on his own.\n\nOok is a really good firestarter. \n\nOgg prefers cooked deer, which lasts longer and tastes better. Ook is hungry - starting fires is a cool skill, but it doesn't feed you.\n\nOgg and Ook trade - Ogg shares his deer, and Ook helps Ogg start a fire.\n\nNothing has changed - there is still one deer and one fire guy, but the transaction has made them both wealthier than they were before - they both now have some cooked deer meat."
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mdrh9 | how a person with an accent sings without the accent. | How does a British singer sound exactly like an American one? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mdrh9/eli5_how_a_person_with_an_accent_sings_without/ | {
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"Folk music perspective: British folk singers open their mouths far and have less \"twang\" and more \"warble\", most American folk singers go the okie/appalachia route and sing with a more closed mouth and more twang. This is why Joan\tBaez sounds more british than Joni Mitchel, even though both are Americans.",
"Let's look at how you learn to do each. Talking you just pick up from the people around you and unless you see a dialect coach no one ever corrects you. Trained singers are usually coached how to maintain pitch and maximize volume. Also in singing 'tone color' or \"tone quality' is very important and every genre has a different preferred color. Think of a singer preforming the Hallelujah Chorus while singing like a country star. Or a gangster rapper. I suspect the brits don't sound like americans, but rather all singers in any specific style strive for the same sound.",
"Folk music perspective: British folk singers open their mouths far and have less \"twang\" and more \"warble\", most American folk singers go the okie/appalachia route and sing with a more closed mouth and more twang. This is why Joan\tBaez sounds more british than Joni Mitchel, even though both are Americans.",
"Let's look at how you learn to do each. Talking you just pick up from the people around you and unless you see a dialect coach no one ever corrects you. Trained singers are usually coached how to maintain pitch and maximize volume. Also in singing 'tone color' or \"tone quality' is very important and every genre has a different preferred color. Think of a singer preforming the Hallelujah Chorus while singing like a country star. Or a gangster rapper. I suspect the brits don't sound like americans, but rather all singers in any specific style strive for the same sound."
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7lcfa0 | why did americans and soldiers hate jane fonda for sitting with that gun in a photo, even though she campaigned so much on the soldiers behalf? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7lcfa0/eli5why_did_americans_and_soldiers_hate_jane/ | {
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"The 1970's were a different time and place. However, even today you wouldn't find much sympathy for a celebrity who appeared sympathetic to our enemy to the point that U.S. Congress held hearings to establish whether her behavior constituted treason or not."
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bjsrx8 | Why does Acetone dissolve Polycarbonate and other similar Polymers? | I am trying to work out the reasons behind acetone dissolving polycarbonate almost instantaneously.
& #x200B;
I understand it is to do with the solubilities of both counterparts, but I cannot find a definitive answer online which is not bound up in paid to access research papers.
& #x200B;
Huge thanks
& #x200B;
Henry | askscience | https://www.reddit.com/r/askscience/comments/bjsrx8/why_does_acetone_dissolve_polycarbonate_and_other/ | {
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"What do you mean by “why”? That’s a gigantic question and it would help immensely to have a place to start. \n\nWhat I can tell you is the reason it dissolves at all is because the polymer chains are not crosslinked. Which is to say, each polymer chain exists independent of any others, they’re only tangled and not chemically bonded.\n\nAcetone is also quite polar, which interacts with the polar groups on polycarbonate and solvates (surrounds) them. Once the PC chains are solvated they can separate from eachother and the plastic starts to dissolve (the chains start to untangle due to the “grease” of acetone)"
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oxvx8 | Is there any scientific backing to the claim: "Strenuous leg exercise and / or high intensity sprinting can promote testosterone production and overall muscle recovery / stimulation?" | I hear it a lot from my gym buddies and even in r/fitness but have yet to see any credible backing to the statement. If part or all of it is true can anyone shed some light on why and hopefully with some citations?
Thanks in advance. | askscience | http://www.reddit.com/r/askscience/comments/oxvx8/is_there_any_scientific_backing_to_the_claim/ | {
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"Vitamin D is known to increase testosterone, & its available to anybody _URL_0_"
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8ef9af | How did Olympus Mons get so big? | askscience | https://www.reddit.com/r/askscience/comments/8ef9af/how_did_olympus_mons_get_so_big/ | {
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"The main impediment to mountain formation is gravity. If a mountain grows too high, the rock at the bottom will be unable to support the weight above it. Mars has lower gravity, and can thus support taller mountains.\n\nAs for how Olympus Mons formed specifically, it's a shield volcano, so lava steadily flowed out the top and spread around the sides, cooling and turning into rock, and increasing the height of the mountain.\n\nAdditionally, Mars has no tectonic plates. On Earth, the crust might move around on top of a hotspot, creating a series of volcanoes, such as in Hawaii, but on Mars, the crust stays put and so the volcano can grow continuously.\n\nEDIT: As pointed out below, a more important factor is that Mars' crust is thicker than Earth's, and can thus support more weight without flexing as much. Mars' crust is thicker because Mars is smaller than Earth. It has thus cooled more over its lifetime than Earth, and the outer layers have solidified more."
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6lc59x | how do they get the different colors that we see commonly in fireworks?? and why aren't there more blue and variations of blue fireworks??? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6lc59x/eli5_how_do_they_get_the_different_colors_that_we/ | {
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"They use them by adding metals to the fireworks. Different metals burn different colors. Iron for Red. Titanium for White. Copper for Green. I think Cobalt for blue? Quantum mechanics really, excited atoms of a given element produce light in a given part of a spectrum."
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3bidom | Why did the Ethiopian Orthodox Church administratively separate from the Coptic Orthodox Church of Alexandria in the 1950s? | Any spicy church politics? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3bidom/why_did_the_ethiopian_orthodox_church/ | {
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"My understanding is that this was Emperor Haile Selassie's doing to better align the church to the monarchy since his legitimacy was in part due to the church, and his interest in African politics diverged his interest away from Nasser's Egypt which was more focused on the Middle East. Around the time of the autocephaly the Egyptians didn't even bother to have a treaty about the Aswan High Dam with the Ethiopians which should well demonstrate how far apart the two were from each other.\n\n This split in focus between the Middle East and Africa is also related to why Selassie is considered the messiah by the Rastafari and not, say, King Farouk. Although the major consequence of the autocephaly was that now Selassie had financial control over the church and therefore pretty much its full support.\n\n\nI'm sure that you are right that there were major church politics between the conservative and more liberal factions of the church, but the primary impetus was Selassi's African political interests after his return to the throne after WWII.\n\n\n For a larger view of the Egypt-Ethiopean political split you should look into Egypt-USSR and US-Ethiopian relationship, The Suez Crisis of 1956, Egypt's and support of the Somalians and Eretrians against the Ethiopians. \n\nHopefully someone who is more of an expert about the cold war politics of the region can give a less cursory answer for you and can dive into the internal church politics. It's actually pretty surprising that there wasn't a schism, but that would have probably been too radical for the Solomonic dynasty's ancient relationship with the church."
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7f7hf8 | what makes any given bacteria inherently beneficial or harmful to humans? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7f7hf8/eli5_what_makes_any_given_bacteria_inherently/ | {
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"In most cases this has to do with what type of stuff the bacteria produces, but also how aggressively it out-competes other bacteria and whether or not it's capable of penetrating tissue on its own. The gut is a good example of some of these variables.\n\nFor example, you've got E. coli in your gut all the time. Most E. coli is not bad for you. It helps break down certain food products so that you can absorb them. However, there are harmful strains of E. coli which are harmful because they produce a toxin. This toxin interferes with your gut lining and makes you really sick.\n\nThen you've got bugs like C. diff, also in the gut. We get exposed to this sometimes but we're just fine. However, when you're on really strong antibiotics, lots of the normal bacteria that helps out in the gut is killed. Dangerous C. diff strains aren't killed so easily, and it will populate all that new space really fast. This one also produces a toxin that'll make you sick when your gut is full of it.\n\nAfter that you've got stuff like salmonella, shigella, and campylobacter. These also produce toxins in most cases, but they tend to go one step further and actively invade the tissues lining your GI tract. Unlike normal gut bacteria, these guys are digging in and that doesn't feel very good.\n",
"A couple of factors play into this.\n\n1. How well can it grow inside the body. This includes how well it adapts to the environment inside our body and also how well it can evade death from our immune system\n\n2. Does it release toxins? This ones kind of a no brainer when it comes to harming the body.\n\n3. How does our body respond to its presence? A lot of bacteria don’t actually damage the cells themselves, but certain components of them activate such a strong immune response that the body actually starts to hurt itself\n\nThose are the three biggest things that make for harmful bacteria. Beneficial bacteria are generally bacteria that can grow within our GI tract that don’t cause us much harm at all in there, but instead outcompete other bacteria that may cause disease ",
"In biology, there's something called symbiosis. Contrary to popular thought, it just means that two organisms are living together and have some sort of relationship.\n\nMost bacteria have a commensal relationship to us. This means that whatever waste we produce, they happily eat and stick around. We don't get any benefit out of it. This is opposed to parasitic, where it leeches off of us like a leech or a vampire (that is, we're suffering because of it). Bacteria often digest stuff that we can't eat anyway so its not harmful.\n\nThough, some bacteria are considered to have syntrophy. This is where we don't need the bacteria, but they help us. This includes bacteria in your gastrointestinal tract and skin. They don't harm us, but the stuff we can't eat, they can eat and then provide crap that they can't use but we can. These include Vitamin K, short chain fatty acids and some can break down carbs we can't into sugar. \n\nGood bacteria can become bad. We're effectively enslaving bacteria by keeping them to certain places. We have essentially guards called lymphoid follicles made of white blood cells that stop them from spreading further than we want. When they do spread too far, they can become pathogenic and become bad bacteria. So the distinction is sort of if they're where we want them.\n\nHowever, there's exclusively bad bacteria like Staph Aureus (Golden Staph). These don't normally live in our body, sometimes can be found on the skin. However, when they get in, their exclusive role is to cause as much damage as possible to get nutrients from our body and then divide/proliferate and then leave, spreading to other people. They do this by producing exotoxins which they secrete causing destruction, or endotoxins. Endotoxins are basically their outer shell which gets picked up by our body as bad. However, if they're released when the cell dies, it harms our body.\n\nThat said, good bacteria also have endotoxins sometimes. But we're not really sure how the body recognises bad bacteria and kills them without killing the good bacteria. \n\nEven funnier yet, there are bacteria that just sit in our body and replicate. They don't really do anything, but as soon as our body recognises and attacks it, we're in big trouble and it starts causing a lot of nasty problems everywhere. They don't have endotoxins or exotoxins. Their destruction is caused by our bodyhurting itself trying to kill it. An example is TB. "
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2o51xc | how do we not run out of food and other natural resources? | It seems like the supply on earth is very limited and I'm surprised we haven't run out of things with the way our current population consume things. How do we do supply ourselves so well without draining the planet dry. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o51xc/eli5_how_do_we_not_run_out_of_food_and_other/ | {
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"There's more on earth than you might think. We produce more than enough food to feed the planet. The problem is distribution - the food is all concentrated in rich countries. Food is basically stored solar energy. Plants use the sun to grow and animals feed off plants. We're unlikely to run out of food anytime without a major catastrophe. \nSame with resources. Shortages are mostly economic. As supplies get scarce people either find substitutes or they mine previously uneconomic deposits. Oil is an excellent example. When the price is high we turn to fracking and shale oil. Now it's dropped down again those supplies will probably stop because they cost too much to produce. The oil doesn't disappear tho' so when the price rises again we will re-open those supplies. Over time we can darn the planet but it'll take a couple of thousand years and by then we could hope to be mining space."
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8d4ili | How did housing/property markets behave following mass epidemics in history like the 1918 Spanish Flu? Did housing become super cheap? What generally happened to homes where the owners/families died? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8d4ili/how_did_housingproperty_markets_behave_following/ | {
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"The short answer is that it's complicated, and the long answer is that, it's really complicated. I can only really answer the first part of the question, and that's a big question at that. \n\nThe problem with analyzing housing markets in the wake of mass epidemics is that plagues have different economic effects depending on the very nature of the disease. For instance, the Black Plague primarily struck down those who were either young or old. From an economic point of view, this creates a supply shock to labor a few years down the road, but that aside from the general chaos and uncertainty that means that the economic damage will not be seen for a few years until the young generation reaches working age. On the other hand, the Spanish Flu primarily struck down healthy young adults due to the nature of the cytokine storm. Thus, it would have an immediate impact on the supply of labor as people who are sick or dying cannot be working. Because of these labor shocks, this creates a few economic drivers: less labor supply against a preexisting labor demand implies that wages will rise. Rising wages means that people can choose to consume more per capita, which could offset the reduced demand by sick or dying people. \n\nGregory Clark, an economic historian of England who has a very nice dataset of prices and wages from England post 1300, discusses how while rental prices were falling in the 1300s right around the time of the Black Plague, that this fall in prices had been going on before the Plague's arrival in Britain and that he suspects that the plague was in fact exogenous to these housing prices. (see: Gregory Clark, Microbes and Markets). \n\nKnoll, Schularick, and Steger, in their \"No Price Like Home,\" come to a similar conclusion with respect to housing prices. They argue that housing prices were more or less constant prior to the mid 1900s as improved transportation infrastructure made the amount of available land for use much greater: that is, with roads, cars, seaplanes, faster boats, and so forth, people can live further away and still be in a position to go to their workplaces in a manner that is time efficient. By comparison, population shocks like the Spanish Flu had a relatively minor impact on housing prices. \n\nBrainerd and Siegler actually wrote a direct work examining the impact of the Spanish Flu on the US economy (The Economic Effects of the 1918 Influenza Epidemic) but they explicitly exclude real estate companies from their analysis and focus primarily on the impact of the labor force. Their conclusions are similar to the ones above: which is to say, there was an immediate labor shock, and wages went up. \n\nGarrett's \"Economic Effects of the 1918 Influenza Pandemic\" also reached similar conclusions. What he also noted was that sick people also had lasting damage in the form of weaker human capital: children with sick parents received less education, for example, making them less economically valuable than say, someone whose family did not get sick and was able to fully attend school. \n\nAs you can see, the answers do not quite get to your question. Part of the problem is that trade itself is also disrupted during a mass epidemic and data may not be as good as it should be: another issue is that property markets were prone to speculation as it was: Wheaton, Baranski, and Templeton noted that in any given decade in Manhattan real estate prices often shifted 20-50% in real value, thus making dissociating the plague effect with other effects very difficult. It is worth noting that although less people may have needed houses (due to epidemic casualties) it is possible that due to their new wages and temporarily lower prices they were able to purchase a bigger place to live, thus offsetting any immediate demand effect. ",
"I have trouble seeing how the pandemic would have made an economy-altering difference, any more than the AIDS crisis of the 1980s affected urban property markets. First, the death toll in the US was only 0.65 percent of the population, although a Metropolitan Life Insurance study *of those it insured* found that 3.28% of that entire population of industrial workers in the U.S. aged 20-50 died. Second, the home ownership rate in 1918 was only around 45% (compared with 65% in the mid 1980s). Third, half of all deaths in 1918 were of people aged 20-40, who (particularly in that era) were unlikely to be property owners."
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7w05uu | why can some large corporations get away with directly attacking other large corporations in their commercials without getting in trouble for slander/defamation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7w05uu/eli5_why_can_some_large_corporations_get_away/ | {
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"Defamation (in US law) is a knowingly false statement of fact that causes damages.\n\n\"X sucks and is dumb and makes bad products\" isn't a statement of fact. It is an opinion, and opinion cannot be defamatory.",
"Technically since it's an ad, it would be libel, not slander which is an oral statement. And defamation is a broader term for either libel or slander. \n\nTake the recent Wendy's ad campaign. The basic message is \"Wendy's tastes better than McDonald's because we use fresh beef and McDonald's uses frozen beef\".\n\nWhat tastes better is a matter of opinion, and you can't defame by expressing an opinion. That McDonald's uses frozen beef is a verifiable fact, and it's not defamation if something is actually true. Making fun of a competitors claim is likewise not spreading an objective falsehood. The McDonald's statement \"our beef is flash-frozen to seal in flavor\" was mocked by Wendy's with \"Remember an iceberg sank the Titanic\". Nothing legally defamatory about that. Now if Wendy's ran an ad that said McDonald's used horse-meat for their burgers and they were contaminated with broken glass and *E. coli*, that would likely result in a lawsuit for defamation since it is neither opinion nor a true fact. \n\nThat \"better\" is subjective is settled case law. Papa John's was sued by Pizza Hut. The gist of the claim was that Papa John's statement slogan \"Better Ingredients- Better Pizza\" was not objectively true. They won in a lower court which ordered Papa John's to stop, but then upon appeal a higher ruled that \"better\" is a matter of opinion and thus not subject to libel.\n\n",
"Take note this is somewhat an American thing, some other countries have tended to be stricter to a degree. Direct gold sales ads are only allowed in India and USA."
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1sovgt | Who lived in the Iberian Peninsula during the caliphate there? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1sovgt/who_lived_in_the_iberian_peninsula_during_the/ | {
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"Your question is a bit broad, so I'll try my best to address it in general terms. Unfortunately, being at work, I don't have access to my source material, so I beg the mods to show me a little mercy.\n\nIn religious terms, you can easily split the Iberian Peninsula into the Catholic north and the Muslim south. In ethnic terms, you have something of a hodgepodge. Before the original invasion, the Iberian peninsula was composed of the descendants of the Hispano-Romans (themselves a mix of the original Celtiberians and Roman settlers), along with the people that would eventually become known as the Basques and a smattering of Jews. The ruling class was composed of the Visigoths, an originally Arian Christian group that became Catholic later on. There were also the Kingdom of the Suevi, but I'm not sure how they were integrated following their submission to the Visigoths.\n\nNow then, after the invasion by the Muslims, you have a large influx of Berber and Arab blood, as the invaders brought their ways and families into the now-conquered Iberian peninsula. The far north remained Catholic. The Kingdom of Asturias was founded by an alliance of the Visigoths and the Basques. Asturias became the foundation for the eventual Catholic *Reconquista* of the Peninsula.\n\nSo, in summary, the ethnic composition of the Iberian Peninsula during the time of the caliphate there would be composed of:\nHispano-Romans\nVisigoths\nSuevi\nBasques\nBerbers\nArabs\nJews\n\nAgain, don't have sources with me now, but happy to hunt for them when I get home."
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2jka90 | why does the air conditioner in my car "smoke" when it is raining out? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jka90/eli5_why_does_the_air_conditioner_in_my_car_smoke/ | {
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"It's more of a mist than a smoke I suppose. ",
"Because there is so much moisture in the air that the evaporator in your car is not able to pull it all out. ",
"It's water vapor, cold air can't hold as much water vapor as warm air. When it's raining outside it's really humid but the air can hold more moisture when it's warm; so when you cool down that air the ability to hold that moisture is lowered."
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1za0ar | How do we target specific cells such as HIV or Cancer cells with treatment while not hurting or killing surrounding cells? | What methods or technologies do we use to separate healthy cells from target cells when creating treatments? | askscience | http://www.reddit.com/r/askscience/comments/1za0ar/how_do_we_target_specific_cells_such_as_hiv_or/ | {
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"That, detective, is the right question. Targeted drug delivery is a large area of research at the moment. If you come up with an effective answer you will make a lot of money. Currently the main stream treatment for cancer is a systemic chemo therapy. it does not target the cancer cells and is why people on chemo wither away. \n\nMany approaches use some sort of encapsulation of the drugs. These capsules can be made in a large variety of ways including proetins, lysosomes, polymers, etc, etc. \n\nI have a paper sitting in front of me right now:\n[Microcapsules ejecting Nanosized Species into the Environment](_URL_0_)\n\nThey create a semipermeable capsule out of polymers which contains the drugs. water is capable of entering the capsule and it swells and will eventually burst releasing its drug cargo. This could be used to deliver the drug to a specific location within the body. \n\nReally this is a very broad question that you could write an entire book about and new advances are being made every day\n\n\n",
"A couple of points to lay the ground work. First, for the most part, when you take a medication, it will travel to all parts of the body. So all cells in the body will be affected. (There are exceptions, of course).\nSecond, the basic idea is to identify differences between the cells you want to kill and the cells you want to leave unharmed. The larger the difference between the normal human cells and the drug target, the easier this is to do.\nNext, we pick a part of the target cell that is different from the human cell and find a compound that affects it. Often this is an enzyme or DNA replication machinery or other essential part of the cell.\nTo take antibiotics as an example, many of them target ribosomes (the structures that make proteins) because human and bacterial ribosomes are significantly different. A drug that binds to, and inactivates a bacterial ribosome will affect human ribosomes very slightly. (This slight cross-over is what causes side-effects.)\nCancer cells are much harder to destroy because they are human cells that have gone rogue. But the basic machinery is still human. In addition, every cancer is unique, though there are patterns in change in different body systems (lung cancer vs prostate cancer).\nMany of our chemotherapy agents target the reproductive systems of the cells since cancer is essentially unregulated cell division. So the drug will kill both cancer cells and rapidly dividing human cells. This is why we see the side effects of chemo like hair loss and nausea, vomiting and diarrhea. Those normal human cells are rapidly dividing.\nIf we can identify differences between cancer cells and human cells, we can find new drug targets. This is done by taking cancer cells, growing them in a lab and identifying specific enzymes, proteins and genes that have been changed. We have all sorts of molecular biology techniques to do this.\nWe have done this with breast cancers, where we identified estrogen receptors as a stimulator of cancer growth. So we developed a drug, tamoxifen, that binds to these receptors and stops the body's estrogen from increasing the growth of the cancer. In practice, after a breast cancer has been diagnosed, it is sent to a molecular diagnostic lab to see if this individual's cancer cells have the estrogen receptor. If so, tamoxifen can be used as chemotherapy."
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e64n8d | how come some drugs cause physical withdrawals (opioids) and others only psychological withdrawals (cocaine) or no withdrawals at all (nsaids) | & #x200B;
||||
|:-|:-|:-|
|||| | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e64n8d/eli5_how_come_some_drugs_cause_physical/ | {
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"a lot of the time it depends on the parts of the brain that they effect along with the symptoms they create when you do them. I know when it comes to medication that covers up pain you have more severe withdrawals and typically physical because your body is trying to maintain the homeostasis that it has learned which in this case would be not having the pain. Psychological could be due to this as well depending on if they have more psychological effects when you use the drug vs. more physical symptoms when you use the drug. I'm guessing this so I'm not 100 percent sure but I'm basing this off of the different neuroscience and psychology classes that I've taken. Also, we've learned that \"neurons that fire together wire together\" so could be due to if they aren't firing anymore the effects of those neurons getting rid of the connection between them. Those are just my best guesses if that helps.",
"It all comes down to whether or not and how a drug affects brain chemistry. \n\nMost withdrawals are due to your brain’s natural tendency to try to counteract the effects of a drug that messes with its normal function. It does this by adapting the brain and body’s resting state to a new normal. For example alcohol is a depressant which means it decreases the activity in your brain. Well the brain likes a certain level of activity so that it can control your body properly, so when you are constantly drunk and your brain activity is too low for its preference it will try to increase its activity to try to re-achieve its preferred normal from before the alcohol was introduced. When you remove the alcohol, all of a sudden the brain is working in overdrive because the set point it adapted to with the alcohol present is now too high. This can lead to seizures and other bad outcomes from the overactivity in the brain. Think of it like this. I (your brain) want to stand in one spot and I don’t want to move. All of a sudden a man (alcohol) comes up and starts pushing on me constantly trying to get me to move. I don’t want to move so I push back hard to try to stay in that spot. All of a sudden the man disappears in a puff of smoke. What happens? I fly forward and fall on my face because lm still pushing even though he isn’t there. That’s what happens to give you physical withdrawals. \n\nFor stimulants like meth, the withdrawals are the opposite (fatigue, depression, etc.) because your brain set a new set point to try to adapt to the drug that is now too low once the drug is removed. \n\nIt also depends on how long the drug lasts whether your body will try to adapt to it. It takes sustained intoxication for the body to try to adapt to a new set point since the mechanisms involved are more long-term than a few hours. I suspect this is the reason drugs like cocaine usually don’t produce withdrawals, since it is relatively short-acting, and staying high on cocaine for weeks at a time is very hard and out of the realm of financial ability for most addicts. But I will admit this specific example I am not entirely sure the reason why you don’t get withdrawals. \n\nFinally, drugs like NSAIDs that don’t alter brain chemistry do not really trigger the brain to try to adapt to a new set-point. You can still develop tolerance from other organs adapting to the presence of the drug (I.e. the liver can get better at breaking down the drug) but since the brain hasn’t adjusted its activity, there aren’t really that many systemic effects when you stop.",
"Physical withdrawal usually results from when your brain/body makes physical changes from chronic exposure to a drug. Opioids are a good example: opioids shut off receptors in your brain that, in part, signal for pain. Overtime, an opioid addict's brain starts making more and more of those receptors. This leads addicts to using greater and greater doses to get the same effect. If they stop cold turkey, there is a ton of pain signals that can now get through, regardless of whether they are actually in severe pain. \n\nPsychological withdrawal is related to how your brain perceives rewards. Physically addictive drugs are also often psychologically addictive. Most recreational drugs (including less dangerous drugs like caffeine) and even things like sugary foods or pleasurable activities like gambling or sex \"make you feel good\" by stimulating your brain to release dopamine, the main signal for pleasure. It becomes an addiction if you can only \"feel good\" when you are on the drug , eating unhealthy food, or doing that addictive activity.\n\nThings that are non-addictive tend to not release dopamine and also avoid triggering your body to overcompensate by making excess receptors."
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436mwt | what is coal ash? is it really bad? are there any good benefits? | The reason I'm asking is because Republic Services' is getting closer and closer to dumping a lot of it in a landfill back in my old hometown. I have no knowledge of what it is,the effects of it,etc It sounds like really bad stuff and I just want it explained to me better. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/436mwt/eli5_what_is_coal_ash_is_it_really_bad_are_there/ | {
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"Coal ash is what's left over when a power plant burns coal. It's mainly silicon dioxide, aluminum oxide, and iron oxide, but does contain some heavy metals, so it can be a problem if it gets in the groundwater.\n\nBut unless you actually eat it or breathe it, it's not especially dangerous. It's often mixed into concrete as a way to recycle it, since it functions similar to Portland cement. "
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6jranz | How are ccv codes on the back of credit cards so secure? | How are those three digits on the back secure enough to prevent fraud using just the front numbers? They're just an algorithm, right? How have people not figured out the algorithms and then used that knowledge to vomit fraud with just the normal cc number, or even more so how have people not created credit card generators that give you a cc number with a matching ccv? | askscience | https://www.reddit.com/r/askscience/comments/6jranz/how_are_ccv_codes_on_the_back_of_credit_cards_so/ | {
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" > They're just an algorithm, right?\n\nWhy would you think that? It's just another set of numbers which makes fraud more difficult (for example, if fishing sites just ask you for your number).\n\nAll in all, the best security method is an intelligent card owner.",
"Its not a checksum, its just another number thats only printed there on the card, and stored at the bank. The number on the front of the card is also on the magnetic stripe. So if something steals the number via a swipe, it cannot be used where the CVV number is required, since they didn't capture that info.\n\nIts just an extra bit of security, sorta like a pin. A little bit more info [here](_URL_0_).\n\n"
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1hsnkt | the appeal of comic book superheroes | I never got it, and I feel like there is something I am missing. Everyone seems to love them (superman, batman, etc.) so much and I would like to join in the fun. What is great about them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1hsnkt/eli5_the_appeal_of_comic_book_superheroes/ | {
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"Superman is the embodiment of the perfectly \"good\" person. He's the one we all wish we could be. He fights crime, saves the world, gets cats out of trees, and calls his mother every week. No task is too small or unimportant. \n\nBatman, we empathize with. The big \"what-if\". If we had his resources, and experienced the trauma of having our parents murdered, what would we do then?",
"You know how ancient societies loved their stories of heroes fighting monsters? Its like that. Superheroes are modern myths. Just like classical myths they serve several functions for the viewer; they allow us top escape into the world of the hero and we can create characters that somehow speak to our society and what we want from it in symbolic language. It's just that instead divine parents they get their powers from accidents.\n\nA few examples might help clear it up. When Superman was created in the 30's he represented not just the the immigrant culture but the change in american demographics. Like many Americans he came from a different society (krypton), a society he was proud of but also was proud of his adopted society as well (earth). He had to balance these two aspects of his life in his two identities. Like a growing number of people he was raised on a farm and came from a blue collar background but had moved to a city and became a white collar worker. Since aspects of american culture have changed he seems dated, but much of his story can still be relatable. The dual identity aspect should be something that many people can relate to at one point in their life. The destruction of krypton and it failure to heed the warnings of its lead scientist reminds me of climate change.\n\nThe X-men are metaphors for almost any oppressed minority who are being discriminated against. Like African Americans or homosexuals the x-men are being vilified by society for something that they have no control over because its just how they were born. At the same time they are an ideal minority because the are advocating acceptance instead of separation. Every time professor x beats magneto we are saying that the ideology of MLK is superior to Malcolm X.\n\nIron man was originally intended as an example of american industry being superior to Russian industry. Readers could cheer an American business man defeating Russian businessmen in exciting and physical ways. With the fall of the soviet union he has changed to suite our changing ideas about wealth. He works to make sure the government is abusing his technology. Instead of punching rival Russians, he takes on corrupt and evil american businessmen. Through his stories we get to see our ideal billionaire triumph over our evil ones.\n\nFor all that overthinking, there is one more aspect to their appeal. There is just something primal about the superhero. Everyone fantasizes about being able to fly or being invulnerable. Iron man wears a suite of armor and shots lasers, every kid knows how cool that sounds.",
"There are the unrealistic ones that most people idolize, and treat as gods. Then, there are the humans who are extremely skilled at a certain thing, and are much more relatable. All it is is another fictional character, but (mostly) with big muscles and/or boobs. Basically; in comic books, the superheroes are trusted with the fate of humanity, and once you have begun to read some, you will understand why people look up to them.",
"Total side note: the best super hero movie is and remains Unbreakable.",
"There isn't much to explain. If it's not to your taste, you're not going to like it. Are you a fan of sci fi or fantasy? Kinda similar to that in a way. Personally, I really enjoy (good) speculative fiction (obviously a lot of it's crap, so you need to get the good stuff) set in imagined worlds or scenarios that could never actually happen. It allows you to explore themes or issues in extreme or exaggerated ways. Not all superhero books try to do that of course, but one good example would be Invincible. In this comicbook series a teenage boy looks up to his father and sees him as a hero, but they fall out and fight a lot and he starts to really hate his father. So far, a very common trope, but the difference here is that the father literally is a superhero with incredible powers. I don't want to spoil it for you, but the crushing realisation the boy experiences, and the conflict created between the characters, when the boy discovers his father is not quite the man he thought he was, is similarly exaggerated from the common everyday experience. So by taking everyday life and amplifying it you can get great narratives. Most importantly though, superhero comicbooks are fun.",
"It's the same reason people watch action movies or read adventure novels. It gives you someone who is already noble or whatever, but then faces a stronger enemy and against all odds defeats them using wit, strength or some other sought after quality. You just gotta find a hero you like. I like the Flash a lot. Also Deadpool. You should play some superhero video games and watch some superhero cartoons and you might get it. I recommend Marvel Ultimate Alliance 2 and Justice League."
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dco8fk | why does hitting someone (or getting hit) hard causes a bruise? why is it blue? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dco8fk/eli5_why_does_hitting_someone_or_getting_hit_hard/ | {
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"A sufficiently powerful impact will cause tissue and capilaries to break meaning you have a hematoma which is localized bleeding under the skin. \n\nNow for some reason some blood vessels like Veins will look blue or purple through the skin, but thats because blood carrying CO2 is darker then the bright red of blood carrying O2.",
"The bruise is blood that has leaked, and is being broken down by the body. The colour of the bruise is dependant on how far the blood has been broken down, so it changes from pink-red to blue-purple to green to yellow-brown over time. \n\nBlood with a lot of oxygen is red, blood with less oxygen is more bluish. \n\nThese colourings from broken down blood also affect the colour of feces and urine."
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cutywp | why there is a "tipping point" for the destruction of the amazon | I keep hearing things like "once we destroy 20/30/40% of the Amazon, we've reached the tipping point, and the rest will follow." what is the science behind this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cutywp/eli5_why_there_is_a_tipping_point_for_the/ | {
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"The trees in the Amazon create their own microclimate causing increased amounts of rain sustaining the conditions for the rainforest. The starting point for the rain is the Bodele depression in the Sahara _URL_0_ the trees prevent the water flowing rapidly back to the Atlantic with the warmth in the area meaning that some of the rain then forms more rainclouds which keep the area wet.",
"In terms of animal life, only so many animals can fit in smaller spaces. So, the less forest there is, the more species are lost. I forget the exact numbers but after a certain amount of loss, extinction and stuff picks up rapidly.",
"Positive feedback loops.\n\nLess trees = less transpiration = less rainfall = less growth = less trees.\n\nAlso less trees = more soil loss = less nutrients = less growth = less trees.",
"As a slight aside - for all of you wondering about climate change and increased CO2 being \"good\" for the trees and that they'll grow more: There is a pre-set rate at which osmosis occurs (the process where water travels from the roots up to leaves). Think of the commercials for Bounty absorbing water. You cannot increase that rate. As the temperatures increase, water will evaporate out of the leaves faster than the tree can draw water from the ground. When this happens the trees die. This is why global temperature increases are so dangerous - the plants stop working. Increasing CO2 levels are just like giving a dehydrated person a potato . . . its food, but they'll die of thirst. As more trees die, less shade, more heat, less trees, etc to tipping point. (edited for spelling)"
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4s860l | Why did the Allies need D-Day? Couldn't they have fought their way in from Italy? | They already had a foothold in Europe no? Why not just re enforce and push through from the south? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4s860l/why_did_the_allies_need_dday_couldnt_they_have/ | {
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"There are a number of issues to consider and I will touch on some of them. This answer is not complete.\n\nFirst I want to point out that no General wanted to follow a pure Mediterranean strategy. This accusation was often hurled at the Brits, but its not true. The British CIGS was always explicit about the goals of the Mediterranean Strategy (as early as 1940), they are as follows:\n\n1. Open the Mediterranean for shipping\n\n2. Draw German reserves South\n\n3. Knock Italy out of the war\n\n4. Hopefully bring Turkey into the War on the allied side\n\nThe eventual invasion of Germany was to happen through landing in Northern Europe.\n\nThe Americans were of course far less interested in this strategy and on all the conferences it was a battle between how much resources would be put into this strategy.\n\nSo nobody had a real plan to end the war without a invasion of Northern Europe.\n\nNow lets address why exactly. One of the major reasons why the Brits wanted to draw German troops South is because how hard it is to supply them there, and the move them, if needed, to another front. Moving troops in on an East-West axis in Europe is easy, because of the extensive railway lines. \n\nMoving troops on a South-North axis is considerably harder. You have the Alps smack down in the middle of Europe, posing a considerable barrier and in the middle of the Alps you have a neutral country, Switzerland, that you could not move your troops through. Once you are over the alps there is plain, but shortly after that, if you go South in Italy, or the Balkans, you will have mountains terrain again.\n\nSo for the same reason British Strategist wanted to draw German troops South, it would have been unviable to do the full invasion of Europe from there. Consider this map:\n\n_URL_0_\n\nClearly its not possible to directly go North from Italy. So you have to go around them, most likely into the South of France. Once you are there, you have to fight your way up France, and then you are at the same point that you would have been, if you had just invaded Europe in the North, just that your lines of supply are far longer, more complex, you would have to do it without as much air support.\n\nThere were some suggestion to push on to Vienna (most notably from Churchill) once they had reached the North of Italy, but by then they had established themselves in France and the Strategy called far reducing the effort from the South. The troupes that the Germans had dispatched South, were now bound there and could not help in the defence of Germany proper. The Strategic imperative of the Offensive was successful and further pushing would be wasting resources on strategically unimportant goal (of capturing Vienna). \n\ntl;dr: From a strategic perspective its much easier to invade from the plains of Northern Europe, its also better because of logistics,terrain and air support.\n\nSources:\n\n- Alanbrooke War Diaries 1939-1945: Field Marshall Lord Alanbrooke \n\n- Allied Master Strategists: The Combined Chiefs of Staff in World War II \n\n- The Path to Victory: The Mediterranean Theater in World War II\n\n",
"As a supplement to /upanick21, I wanted to suggest that even if the Allies had decided by the Summer of 1943 to pursue a Mediterranean strategy first, the events in Italy made that plan sour. Progress up the peninsula was very slow going, and by January of 1944 the attempt to open up a beachhead at Anzio was not going very well at all. Invasion of northern Europe must have been a very difficult decision given the events at Anzio. The German resistance in Italy was supposed to be inferior to that in France, and it was thought that the allies had hit Anzio with complete surprise."
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2hc8rj | How does your body know when it needs to breath? | If you had a way to oxygenate the blood but bypass the lungs and you held your breath would you still get the urge to stop holding your breath or does your body know how much oxygen it has flowing? Would you still feel the need to breath even though your blood is fully oxygenated? | askscience | http://www.reddit.com/r/askscience/comments/2hc8rj/how_does_your_body_know_when_it_needs_to_breath/ | {
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"If someone were able to create a way to oxygenate the blood intravenously, we would not need to breathe through our lungs so long as they also created a way to get CO2 out of the blood. Surprisingly, our urge to breathe is caused by the buildup of CO2 in the lungs, not necessarily a lack of O2 (although there is a correlation). "
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pg7yw | Apollo 13 - Why did it get so cold, isn't being in space like being in a thermos ?? | Saw the movie Apollo 13 again the other day. Was wondering why did it get so cold in the Lunar Module with 3 astronauts and a bunch of running electronics ??
I know that they had to shut down the electronics to save energy but prior to that the astronauts were at a comfortable temperature and presumably the electronics were running and generating heat. With so few molecules for the craft to transfer its thermal energy to in space it seems to me that the only way to dissipate thermal energy is by emitting electromagnetic radiation I guess predominantly in the IR range.
On earth you don't think of losing heat by radiating it all away, usually you pass it on to air, water or some other thermally conductive medium.
TLDR - Wouldn't it be hard to dissipate heat in space? Is EM radiation how the Apollo 13 crew was losing heat in the Lunar Module ?? | askscience | http://www.reddit.com/r/askscience/comments/pg7yw/apollo_13_why_did_it_get_so_cold_isnt_being_in/ | {
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"Radiation dissipates heat whether or not in a vacuum.",
"I think it was skylab that needed a [replacement heat shade](_URL_0_) to prevent over heating.",
" > isn't being in space like being in a thermos ??\n\nNot really -- the background temperature of space is 2.7 kelvins, or about -270 degrees Celsius. The astronauts were able to use the available sunlight to increase the temperature of their crippled craft, but this didn't prevent the average temperature from being quite cold, and while they were in the moon's shadow, they were very cold indeed.\n\nJust remember how cold space is, in the absence of a local source of heat like the sun. Imagine standing on the moon, in the shadow of a mountain, or during that part of each lunar month when your location is fully in shadow -- the temperature of your environment is scarcely above the background temperature of space, 2.7 kelvins.\n\n > Wouldn't it be hard to dissipate heat in space? \n\nAs a NASA design engineer, I had to deal with this issue regularly. In a vacuum, heat is only dissipated as radiation, one of three common ways to dissipate heat. Also, in a free-fall, zero-g environment, heat doesn't rise through any available atmosphere, instead it pools around the source of heat, reducing the efficiency of \"heat-sinks\", devices used to move heat away from a heat-sensitive electronic component.\n\nBut in general, because in a vacuum heat will radiate away as electromagnetic radiation, one can usually design a way to get rid of unwanted heat energy.",
"Not to bust your chops, but this was asked [last week](_URL_0_)\n\ndrzowie gives a good breakdown with some heat transfer rates.",
"The reason you lose so much more heat in space is because on earth you are losing heat energy via blackbody radiation, but you are also gaining heat via blackbody radiation from all the objects around you. In space there isn't much around to heat you up. It's like poking a hole in a jug of water and filling it up at the same time, you'll get an equilibrium. Not so in space."
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3o11po | why does the recruiting/hiring process for most jobs move so ridiculously slow? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3o11po/eli5_why_does_the_recruitinghiring_process_for/ | {
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"I work for a natural gas company. We have 1 engineering department. HR collects applications, but it's up to the engineering manager to determine out of all of the applicants which ones should qualify for an interview. In the meantime, that manager has a full day of work to do. Also, jobs are open for a certain amount of time, so from job posted to posting closed will be a couple of weeks before they look at the application/resumes.\n\nHuman resources won't be the ones who hire you, interview you, etc unless you're applying for a job at fast food. They're the ones that will hand your applications to the manager and manage your benefits after you get hired. If it's taking a long time, it's because the department that needs an employee is short-staffed and has to do their normal daily business.\n\nI'm in Information Technology, and for IT, you almost exclusively are brought in through consulting houses (fancy temp agencies) or referral via vendors (we use EMC for our data storage, so we would ask them if they know people who need a storage job, etc).\n\nIf you're looking to move faster, see if you can find your equivalent engineering placement agency, or try joining a startup company."
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6x4cbx | why most ammunition's dimensions have decimal number instead of round number? | Such as 7,62x49 instead of 7,60x49, and 5,56x49 instead of 5,50x49. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6x4cbx/eli5why_most_ammunitions_dimensions_have_decimal/ | {
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"A reason for some strange values is that they were original designed in inches. \n\nThe 7,62 are developed from the .30-06 Springfield cartridge where a diameter of .3 inches was used. \n\n5,56 is derived from a .222 inch cartridge where the value make a bit more sene\n"
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1mha6b | How did ancient Romans get to things on time? | I don't think that Romans walked around with sundial wrist watches, so I suppose I'm just asking how they could get to places by a certain time when necessary? Did they even have the same concept of hours that we do today? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1mha6b/how_did_ancient_romans_get_to_things_on_time/ | {
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"They did it as everyone else before the wide distribution of clocks, they measured time by the position of the sun on the sky. Day was divided into 12 hours, however they differed in length based on season. In summer days were longer, so also hours were longer.",
"FYI, there's a relevant post in this section of the \"popular questions\" wiki*\n\n[Waking up without alarm clocks](_URL_0_)\n\n*see the \"popular questions\" link on the sidebar, or the \"wiki\" tab above"
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k6drx | why is the swiss national bank saying it will buy all other currencies in unlimited quantities? eli5 | _URL_0_
I don't understand economics! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/k6drx/why_is_the_swiss_national_bank_saying_it_will_buy/ | {
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"The Swiss Franc is actually too strong verses other currencies right now. This sounds like it would be a good thing and too a degree it is but Switzerland relies on exports as a major part of its economy and if no one can afford your exports then you have problems so they wanted to cap the value of the Franc verses the Euro at 1.2 Euros per Franc. \n\nNow capping your currency on paper is one thing but actions is louder than words so they feel they have to enforce this by buying the crap out of currencies in an effort to make the market do what they want it to do. The idea is, we set the cap, now we are going to buy currencies and make the currency market follow what we are doing.",
"Maybe not quite at the 5-year-old level, but here's a good podcast about this topic: _URL_0_\nAnd a blog post: _URL_1_\n\nThe gist is that because of all of the uncertainty in the markets, a ton of investors have been buying up the Swiss Franc over the last couple weeks drastically inflating its price and making their exports too expensive.",
"How much does one who lives it Switzerland earn? - could you work in Switzerland buy currency and retire in america like a king? ",
"The Swiss Franc is actually too strong verses other currencies right now. This sounds like it would be a good thing and too a degree it is but Switzerland relies on exports as a major part of its economy and if no one can afford your exports then you have problems so they wanted to cap the value of the Franc verses the Euro at 1.2 Euros per Franc. \n\nNow capping your currency on paper is one thing but actions is louder than words so they feel they have to enforce this by buying the crap out of currencies in an effort to make the market do what they want it to do. The idea is, we set the cap, now we are going to buy currencies and make the currency market follow what we are doing.",
"Maybe not quite at the 5-year-old level, but here's a good podcast about this topic: _URL_0_\nAnd a blog post: _URL_1_\n\nThe gist is that because of all of the uncertainty in the markets, a ton of investors have been buying up the Swiss Franc over the last couple weeks drastically inflating its price and making their exports too expensive.",
"How much does one who lives it Switzerland earn? - could you work in Switzerland buy currency and retire in america like a king? "
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3ud93r | How much can your internal body temperature fluctuate? | Whenever you might be sick the doctors check your internal body temperature with the mouth thermometer thing, and it's usually like 98 degrees or something like that.
My question is, if I were to get super cold by standing out in the snow or something, how much could my internal body temperature change before I die or start feeling sick? How important is it that our internal body temperature stays close to 98? | askscience | https://www.reddit.com/r/askscience/comments/3ud93r/how_much_can_your_internal_body_temperature/ | {
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"Short answer: ultra super mega important. Keep warm in the cold.\n\nLong answer:\nThe normal body temperature of a human is around 37 Celsius, depending on where you measure it and what you're doing. \n\nA drop to 35 core temperature is defined as hypothermia. You start shivering and feeling confused and things progress from there.\n\nA body temperature of 40 is life threatening. Neither of these are enormous variances in temperature in everyday life, but for our bodies temperature is TIGHTLY controlled. It has to be! Your enzymes, the proteins that catalyse all the chemical reactions that makes your life possible, work at a very specific temperature range too cold and they don't work well enough, too hot and they irreversibly change shape and cease to work. That's called denaturation.\n\nEnzymes are also very sensitive to pH... which is why thay too is tightly controled. Even slightly more acid or alkaline blood is a sign of serious problems with your kidneys at the very least, and requires immediate medical intervention.\n\n"
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f17lju | Why is Poland, despite having been under socialist rule, a very catholic nation today, but East Germany, also ruled by socialists for decades, is very atheistic? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/f17lju/why_is_poland_despite_having_been_under_socialist/ | {
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"A similar question was asked [here](_URL_0_)",
"It's a common misconception that Poland has always been an exceptionally religious country. While Catholicism is a defining feature of the Polish identity, in the medieval and early modern period this was no more extreme than the emphasis any other European state placed on its faith. But today, Poland is one of the world's more religious nations, and irreligion fares relatively poorly in Poland relative to the rest of Europe in particular. Poland's religiosity, at first glance, might not have a massive historical precedent. In fact, Polish history differs greatly from the histories of more religiously intense nations because of its remarkable and unprecedented advances in the realm of religious freedom. Examples include the Kalisz Privilege, which stemmed the flow of antisemitism in Poland, and the Warsaw Confederation, which states \"the Archbishoprics, Bishoprics, and other benefices of all sorts, are to be given to no other clerics than those of the Roman Church, indigenis Polonis, juxta statutum. And likewise the benefices of the Greek Churches shall be given to the people of the Greek faith\". In plain English, that says \"no government official may appoint a religious official, and no official of one religion may appoint an official of another religion\". So, in this sense, the history of Poland actually sees a *decreased* emphasis on religion relative to its neighbors and peers, as the state keeps its hands out of the faiths of the people.\n\nSo, what gives?\n\nIt all stems from the destruction of the Polish-Lithuanian Commonwealth, which resulted in Poland and its people coming under the occupation of primarily the Russians, but the Germans (technically Prussians) and Austrians as well. First and foremost, religious tolerance among Poles became a non-issue because they didn't run a multiethnic state, or any state at all for that matter; suddenly becoming an oppressed minority themselves, religious tolerance at any level of government was out of their hands. That's not particularly what's relevant though. What matters is, the Polish people found themselves outcasts, and every day brought a new challenge to their sovereignty even at the local level. The Polish state could no longer vouch for the interests of the Polish people, as it did not exist. So, the Poles turned to the Catholic Church throughout the 19th century for strength and support. This was the real genesis of Poles as an exceptionally religious people. The Church tied issues of anti-Polish sentiment among their partitioners to the Pope, still an extraordinarily influential figure, as well as to French sympathizers with the Polish cause. Although Polish pro-French legions during the Napoleonic Wars exhibited skill and bravery which were unprecedented for a people who were seen as too weak to assert their independence, it was too little too late, and the Poles would remain subjugated for another hundred years with only the Catholic Church as an actor on their behalf. As a result, the bond between Poles and their faith deepened. As Neal Ascherson puts it in *The Struggles for Poland*, \"After 1795, the Catholic Church became the main institution which preserved and defended Polish culture, language and identity against foreign oppression\".\n\nGermany during this same period, although deeply intertwined with Polish history, does not share these same features. Bismarck, right-hand man to the German Kaiser, is known for shattering the kneecaps of Catholic authority in Germany through his *Kulturkampf*, but this cultural and legal movement involved certain restrictions on Protestant officials as well. For example, Bismarck made it so that educators throughout Germany would be appointed by the government, not by any Christian denomination. Bismarck wanted a secular Germany. \"His central purpose was to destroy or at least disable any institution which challenged the absolute authority of the German state.\" - Ascherson again. While the Polish became increasingly Catholic, the German people found that their powerful state, something which the Poles sorely lacked, was the primary guarantor of their security and power, and so were less reliant on any church.\n\nMy knowledge of the GDR is rather fuzzy, so I won't comment on that for fear of making false assertions, but Ascherson goes in depth about Polish Catholic resistance to the Soviet regime. In fact, he asserts that attempts to institute Soviet state atheism only caused patriotic Poles to cling steadfastly to the Church in defiance. Brutal repression under Stalin kept the average Pole silent, but on the eve of his death there began to be openly anti-Soviet (or at least anti-Stalinist) thought, punctuated by the 1955 Warsaw World Festival for Youth and Students which brought the reality of Western wealth to Poland as well as allowing Poles to interact with and experience the lives of their German and Czechoslovak neighbors. The anti-Stalinist Khrushchev Thaw, which led to mild relaxation of communist policy. was reflected in Poland through a smaller-scale Golmuka Thaw, named after the head of the PZPR, the Polish communist party which exercised control over the country. The whole Cold War period saw periodic strikes and uprisings but anti-Soviet sentiment reached a peak when Pope John Paul II, a full-blooded Pole, took the mantle of head of the Catholic Church. As he himself said, \"The exclusion of Christ from the history of man is an act against man\", and nationalist Poles rallied to this idea. To them, John Paul II was the human culmination of everything they fought for. This was the immediate precipitator for the Solidarity movement, which is often accredited to being one of many immediate causes of the collapse of the Soviet Union, although it was a symptom of a widespread disease of repressed peoples and a stagnant economy in the USSR.\n\nYou can find *The Struggles for Poland* [here](_URL_1_), and full English translations of the [Statute of Kalisz](_URL_0_) and the [Warsaw Confederation](_URL_3_) are available online. Not mentioned is *God's Playground*, a comprehensive history of Poland which is considered the authoritative English-language work on the subject. It can be found [here](_URL_2_) (note that it's two volumes but I linked the second one because its material is relevant for this topic), but note that Ascherson's text is generally more geared towards readers interested specifically in Cold War Poland.\n\nIn a sentence, the Catholic Church's support of Polish sovereignty and self-determination during long periods of repression and occupation of Poland led to an extraordinary bond between Poles and their Church which defied two full centuries of German, Austrian, Russian, and Soviet attempts to extinguish it."
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601zze | why is china's role in ww2 such uncommon knowledge? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/601zze/eli5_why_is_chinas_role_in_ww2_such_uncommon/ | {
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"In the United States, it's because the war on Germany took precedence, so we learn more about the Western Front, briefly touch on the Soviet Union and the Eastern Front, and our experience with the other side of the world is mainly limited to the Pacific War with Japan. China's not covered because, to be honest, the vast majority of our servicemen were deployed elsewhere. All we ever hear about from the Chinese Theater of Operations is the Flying Tigers.",
"One reason is because it makes the chinese communist party really upset when you remind everyone that the only reason they are in power is because the actual democratic people's republic of china lost all it's military power fighting tooth and nail with the japanese imperial army. Mao Zedong's communists basically laid low like a bunch of opportunistic cowards during the war while the japanese raped and murdered everyone, and then moved in to take over the country after the republican government had exhausted all its man power. Then they went out of their way to rewrite history and pretend that they were actually the saviors of the people/fought the japanese. Since china is an important trading partner and chinese culture puts a huge emphasis on the concept of face (face basically means public respect), we all collectively agree to ignore it.",
"Much of China was occupied by Japan before and during WW2. China was also still largely an agricultural \"peasant nation\", not industrialized nearly the extent of Japan or western powers. Thus their capacity to mount resistance was limited. Their main role (from the allies' standpoint) was to force some extent of japanese troops tied up defending the territory, raid supply lines, sabotage war resources. Their history during WW2 is limited because their impact on the war was limited. ",
"After the war, our government was worried that Japan would become communist like Russia and China. A lot if the atrocities committed by Japan weren't made public since our politicians wanted to rebuild and make an ally of them. They wanted a presence in the region. There was really no way to talk about China without talking about what the Japanese did there.",
"Well, to sum it up simply, Japan had already conquered much of Asia by the time the US joined the war and those parts were generally not liberated. Japan still held that territory when they surrendered to the US, and during that part of the war Russia swept in to claim territory for the communists.\n\nIt made for a somewhat awkward ending to the whole thing and the Soviet land grab at the end sort of triggered the cold war stance that followed.",
"One of the simple reasons is because we call it the \"Pacific War\" on the eastern front. Where and when did it start? Pearl Harbor, December 7, 1941. This entirely takes out the starting point in which Japan began hostilities against China, September 18, 1931 during the Mukden Incident. An entire decade had passed before the USA joined the eastern front, but we don't even bother to mention it.",
"The history of countries that sometimes cause the US aggregation are seldom studied in depth in grade school. Very few people know about the rape of Nanking who haven't done some digging and research out of real curiosity because it's not talked about often. You could say the same for Vietnam before the war, or Korea before the war etc. World history is painted in with the broadest of strokes. ",
"China Marines and the Flying Tigers etc? Those were the main things other than Role as victims of the Japanese I knew of growing up.\n\nDisney doing the Patch for the Flying Tigers and Newsreel stuff.",
"Here in Britain we learnt about it. The Burma road and all.\n\nI'm really starting to feel like American teaching of history sucks.\n\nWho won the war in Europe? The Soviets obviously, I think the right statistic is for every German that died fighting Americans or British, 30 died fighting the Soviets. Yet you talk to Americans and they make out they won the war single handly. \n\nYea cheers guys thanks for selling weapons to both sides, getting rich then only joining the war when Hitler directly declared war on the US. ",
"The Rape of Nanjing occurred, where Japanese soldiers seized control of the Chinese capitol (at the time) and raped/killed as many people they could find. At the same time, Japan committed a lot of messed up medical research during WW2 through torture, some may say even worse than the Nazis did. Unfortunately, these findings were deemed important to the U.S., as they could help advance the search for cures of some diseases and other things. The U.S. made a deal with Japan to obtain the medical discoveries in return for no punishment for the Rape of Nanjing.\n\nIf this deal never happened and the Japanese got their rightful punishment for their crimes, I am very sure that we would hear of China's role in WW2 more often than we do now.\n\nWhat's even more messed up is that medical researchers would have made a *portion of these medical discoveries sooner or later. So stupid.\n\n*Edit: A portion, not all",
"It's well know in the majority of the world. The US education system is based on glorifying the US role. \n\nThis is how the fact that the US didn't help the Allies in Europe (particularly France) until ¾ of the way through WW1 isn't well known. And then it didn't want to help Britain and Europe in WW2. It demanded all of Britains wealth for assistance and sent it broke. No one remembers that either. \n\nSo it suits the US image of itself to tell the history that makes itself look good. \n\n",
"I was unaware of the atrocities committed by Japan in China until in undergrad my Chinese history professor gave us a good couple hour lecture solely on the subject. Eye opening to say the least. ",
"Because it ended with Mao, and it's a lot easier to forget why Mao got power and just accuse him of mass murder. It's hard to have an in-depth understanding of the factors that led to his popularity and still blindly accuse him of horrible things.",
"Because the nationalists lost the chinese civil war, a lot of WW2 history was used in favor of PRC propaganda. Little did people know that the communists ambushed the nationalist soliders in 1940, killing 40 thousand of them in one single battle while ignoring Japanese troops some 50 miles away.",
"The massacre of Nangking was awful. The Japanese had no humanity in such atrocious acts against the Chinese. ",
"It's due to the post war hostility towards communism. \n\n\nEssentially, there was two stories of WW2. The one that really happened, and the one where the US sallied in and kicked everyone's ass.\n\n\nNow guess which version cold war high school class rooms were teaching.\n\n\n\nThe result is the current state of affairs with a bizarrely warped perception of how and by whom WW2 was fought that persists to this day.",
"Yeah I'm from the NL and you can already guess what we talk about most. We did a really cool thing though where the teacher gave us a couple of subjects and we had to make a presentation about one of them. I chose operation barbarossa as it isn't that well known and I am a history fan. But I think western countries don't talk about the stuff they weren't involved in that much. I don't know about the situation in Germany or Japan but you'd think they'd learn more about the Eastern front and China. ",
"It's not well-known because we as Western countries wrote a history that shoehorned the China-Japan-Pacific conflict into the European-centered war. That's not necessarily wrong: the Japanese did attack European and American territories, and they did that (ultimately) because of their conflict in China. These things are absolutely connected. But the idea that China was a nation like Western nations, and that it had a \"role\" in the war like France or New Zealand is not quite accurate. China was horribly complicated in the 1930s.\n\nSo in China the Second World War has to be discussed in the context of their history. Most countries in the war operated together. We call the winning side \"the Allies\" because- with a few serious exceptions- they collaborated closely. China had the benefit of aid from the Soviets and Americans, but they did not have the ability to project power into other theaters or provide men or material in return. They didn't cooperate internally, much less with other governments on other continents.\n\nChina didn't even have a single government: it was a quilt of warlord territories, most of which had been assembled together by Jiang Jieshi (Chang Kai-Shek) into Kuomintang (Nationalist) territory like a syndicate. The Communists under Mao Zedong controlled roughly one province. Other warlords and potentates controlled their own provinces and regions, including places that still give the Chinese government a headache, like Tibet and Xinjiang out west. The efforts each government made differed too, with the Communists putting up remarkable resistance when they faced off against the Japanese, and the Nationalists losing ground continuously for eight years.\n\nWith all that in mind, it was not realistic to expect the Chinese to do much outside of China. Their place in the history of the war is crucial, but the story that we tell- about industrial superpowers, an engineering arms race, intercontinental strategy, and the wills of mad men- doesn't really fit with the events in China.\n\nSource: wrote thesis on China in the 1930s, lived in China for several years.\n\n\nFor my pet theory: the conflict with Japan should be put in the context of Chinese history broadly, under the idea that China has a cultural center (including places like Sichuan, Shanghai, and Bejiing) and a cultural border (including places like Japan, Manchuria, Vietnam, and Tibet). Every few centuries one of the border countries rides in and tries to take over the center. The Mongols and Manchus pulled it off. The Japanese tried but failed.\n\nThat theory will probably not hold water, but I'd like to try it out on some Japanese people anyway. \n\n\n",
" > **It’s a good reason to remember that on its own. I would say that one of the single facts, which is worth remembering if you want to annoy an official in the Chinese Communist Party, is to remind them that the reason, the primary reason, that China today has a seat in the permanent five on the United Nations Security Council, the top table of global diplomacy, is not because of anything that Chairman Mao did. It was because of the wartime efforts of Chiang Kai-shek, and essentially as a direct result of China’s involvement on the Allied side in World War II.**\n\n > China now finds itself — more than 65, 70 years nearly after the end of World War II — as the only non-European, non-white power to sit at that top table. So these things do have a great deal of significance today.\n\n > **When were they forgotten? Put very simply, China’s wartime experience, suffering, and contribution to the Allied cause fell into a hole created by the Cold War. Neither side had an interest in recalling what China did.**\n\n > On the Chinese side, after 1949 when the civil war was over, the Nationalists had been exiled to Taiwan, and Mao was victorious on the mainland, you had essentially a virgin history in the mainland of China — that the only people who had made a contribution to fighting and defeating the Japanese were the Chinese communists.\nThe contribution that had actually been made by the much larger Nationalist army was essentially either dismissed or wiped out of the official history that was taught in China itself. So there’s sort of an historical black hole there.\n\n > But we can’t put any of the responsibility by any means on the Chinese communists on the mainland. You have to remember that in the West, we very quickly forgot about that wartime contribution as well. The reason is that Chiang Kai-shek, the Chinese wartime leader, was essentially seen as a sort of embarrassment — this Cold War relic remaining on Taiwan, looking more and more irrelevant year by year, associated with incompetence and corruption, with a whole variety of qualities that the West didn’t find very attractive.\n\n > But what was forgotten was the leader, through a whole swath of decisions, many of them very problematic and difficult, had nonetheless kept China in the war against Japan. First of all, on his own for about four and half years, and then of course as part of the very difficult alliance with the West for another four years after that.\n\n_URL_0_",
"Usually in school, we just learned a handful of events (Pearl Harbor, Normandy, etc) and then to make it easier they just lumped countries into the good (US, GB, USSR, France) or bad (Germany, Japan, Italy), while China's role was a bit more complicated than a public school teacher would want to get into.",
"The same reason we think America won the European conflict despite Russia killing 90% of all Nazi forces, almost all the tanks and the eastern front being the clear deciding front of the war. Germany pulled forces away from the west, even after D-day, to stop the Russians, and some German officers intentionally surrendered early so that Britain/America could get to places before the Russians.\n\nThe west talks about the west kicking ass because the western soldiers came back with their stories. Very few Russian soldiers came back to make Hollywood films about the Eastern front. Very few Chinese soldiers made Hollywood films about their experiences. ",
"Not a direct answer but relevant. I'm travelling in China right now and got discussing history in general, Chinese history and Mao, the cultural revolution, the wars etc with some native Chinese young people I met at a hostel. They were mid twenties probably, and when we got discussing ww2, (which incidentally here they actually call 'the anti Japanese war'), none of them even knew who Adolf Hitler was. I mentioned his name, but they had not the slightest idea, never heard of him. Only one of them slightly recognised him when I showed them some pictures on the Internet. \n\nHistory is more often than not centric to where you live. They couldn't believe I'd never heard of x amount of Chinese and Japanese folks that they all know, the same way we know of Hitler and goring and goebbels (im tired forgive me for the spelling). \n\nSo in the west, we focus on the Germans, France, the UK, the US whereas here they basically learn, 'Japan was bad'. \n"
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20ir1m | What are some things that JFK would have had in his briefcase during the height of the Cuban Missile Crisis? | Working on a creative project for my first year history class, I'm going to fill a briefcase with some items that President Kennedy would have been carrying.
Here is what I have so far:
• Map of Cuba
• Satellite images of Cuban missile bases taken by U-2s
• Document with parts blacked out
• Picture of Marilyn Monroe with a lipstick mark
• Anti communism ad
• Something leading up to his Dallas trip → map, hotel, travel brochures, etc.
• Pill for back pain (health related)
• Military budget list
• Decoder
• Naval insignia on the brief case
THANK YOU FOR ANY INPUT FELLOW HISTORIANS/HISTORY LOVERS!
UPDATE:
So as CarrionComfort mentioned the items I planned to use were not exactly historical or in order so i changed the project a little. Because I needed to convey a message I filled the briefcase with things that JFK would have had in the days right over the failure of the Bay of Pigs Invasion. My message being that the failure made JFK and the US look weak.
I included:
Map of Cuba
Fidel Castro mug shot, photos
Condolence Letters to the families of pilots killed
Letter from the CIA regarding ZIS-5 trucks & diagrams (the trucked used to move captured ex-Cubans)
Pre and Post attack maps
Rescue map of Cuba
Marilyn Monroe photo with lipstick
Pill bottle
Letter from Khrushchev
Blueprints of B-26 aircraft
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/20ir1m/what_are_some_things_that_jfk_would_have_had_in/ | {
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" > Document with parts blacked out.\n\nWho would be censoring things from the President?",
"Is this a \"pop history\" approach? Many things in there aren't historical, seeing as many of them are anachronistic, don't make sense or cannot be back up with evidence. \n\nWhy would he have an anti-Communism ad? The Cuban Missile Crisis happened a year before he went to Dallas, so those wouldn't be anywhere near each other. Decoder? That is other people's job. I trust you can see where I am going with this.\n\nBut if you are collecting items that are symbols of things the Kennedy is known for, that's fine. Something about the hotline to Moscow? A child's toy, as he was a father. A condom if you're feeling cheeky. \n\nLastly, this may seem better suited for /r/history than /r/AskHistorians ",
"You could include a copy of spy who loved me Kennedy was a big James Bond fan in fact he saw an early print of from Russia with love at the White House in 63. Also unless you are doing it for a reason anything to do with Dallas would be not accurate as that trip is over a year away from your date.\n"
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68tduf | why do people in the us refuse pay raises to not get into higher tax brackets? | Is it because people do not understand how tax brackets actually work?
EDIT: I should've put "some people" in my title, now I sound really passive aggressive. My bad | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/68tduf/eli5_why_do_people_in_the_us_refuse_pay_raises_to/ | {
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"I never heard of that before, but if some people do that, it's because they don't understand how tax brackets work.",
"People think that if they get a raise that it will push them in a higher bracket and they'll overall net less income overall. \n\nThis isn't true thought because the tax brackets are marginal. This means the first $X amount is taxed in bracket 1, the second $X amount in bracket 2, and so on. ",
"Its not just about tax brackets, which other replies in this thread seem to maybe not understand.\n\nLets say I have a family of 3 with an income of $80800. With this, I see an estimate of [$8270 financial help](_URL_1_) with insurance. If I get a $1 raise, putting me at $80801, [I lose all of that assistance](_URL_0_)\n\n",
"There are a few things.\n\n1. Is a misunderstanding of how the income taxes work. With marginal rates, you only pay the higher tax rate on income above that amount. So if you make $50,000 and the tax rates are 10% on the first 15,000, 20% between 15,000 and 45,000, and 25% on everything above 45,000. You only pay 25% on the last 5,000, 20% on the middle 30,000 and 15% on the first 15,000.\n\n2. Is a real concern thanks to the stupid way most welfare type programs works. Many programs are setup only to provide benefits below an income threshold, so maybe you get $2000 of food stamps if you make less than $10,000 in income. So if you make $9,999, you get an additional $2,000 in food stamps, given you an effective equivalent income of $11,999. But if you income goes up $1, you no longer qualify for food stamps, so now you effective income is $10,000. This discourages raises because people will be worst off unless the raise is high enough to offset it. This is terrible design, and could be mitigated by having a gradual reduction, i.e. you lost $.50 of food stamp benefits for every dollar of income above $8,000 so that you are always noticably better off making more money. "
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3fpque | If the Modern German State was born out of the Kingdom of Prussia, why did the Potsdam Conference decide to move the Eastern border of Germany to the Oder-Neisse Line rather than removing non traditional Prussian lands like Bavaria or Baden? | I've never really understood the specifics of the decision. What made the Allied parties decide to remove that part of Germany versus other areas?
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3fpque/if_the_modern_german_state_was_born_out_of_the/ | {
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"Two reasons: \n\nFirstly, the move of the border to the Oder-Neisse line was a way of compensating Poland for the eastern Polish territory that Stalin had claimed for the USSR. The western allies argued hard for this adjustment, not least in recognition that it was about the best deal they were going to get for Poland. \n\n* Source: *1946: Making the Post-War World* by Victor Sebestyen. \n\nSecondly, the allies decided to abolish Prussia entirely - although the state had not really been a driving force in Nazi Germany in the same way it was in Imperial Germany, it was still held to be a repository of German militarism and conservatism. Konrad Adenauer in particular argued for the abolition of the name of Prussia and the reorientation of Germany towards the west along the Rhine. \n\n* Source: *The End of Prussia* by Gordon A Craig"
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1mdzjl | why does gold of the same amount of karats look different colors? | Beyond rose gold and white gold, why will some gold have brighter more yellow color thank other, even if it is the same amount of karats? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1mdzjl/eli5_why_does_gold_of_the_same_amount_of_karats/ | {
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"The carat unit is the level of purity of the gold. If it's less than pure gold (24k) then the gold has been mixed with other metals. The various other metals create variation of colors.",
"It is common for manufactures to plate low carat gold with a higher quality to make it look nicer in the shop. _URL_0_ ",
"There are 4 different types of gold (Red, Green, Yellow, White) they look different at different karatage.",
"Great question! Karats refers to gold content only. The formula is 1 karat = 24x(mass of gold)/(mass of material). so 100 grams of pure gold is 24x100g/100g = 24 karat gold. However, if you have 12 karat gold such that 24x(50g pure gold)/(100g material) = 12 karats, that other 50g can contain other metals. \n\nAssuming that your jewelry isn't plated in any way, different colors arise from different alloying agents. [Here is a chart of what these alloys may contain.](_URL_0_)\n\nHope that answered your question!!"
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3ulbs9 | Implicit Egotism: Does your name affect your personality? | [deleted] | askscience | https://www.reddit.com/r/askscience/comments/3ulbs9/implicit_egotism_does_your_name_affect_your/ | {
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"Since names and the location of your birth are obviously not correlated then I can't see how there's anything of interest from going that direction. It is likely that names are geographically distributed. That is, they're often used in a subculture and that subculture lives in a certain area. But I don't know of anything I've read to support the relationship between a person's name and their profession or choice of geographic location."
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3guofv | how are the words in phonetic alphabets (such as the nato phonetic alphabet) chosen and why have they changed over the years? | How were the words chosen? Why have they changed in the past?
The NATO Phonetic Alphabet: Alpha, bravo, charlie, delta, echo, foxtrot, golf, hotel, india, julliet, kilo, lima, mike, november, oscar, papa, quebec, romeo, sierra, tango, uniform, victor, whiskey, x-ray, yankee, zulu | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3guofv/eli5_how_are_the_words_in_phonetic_alphabets_such/ | {
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"From _URL_0_:\n\n > The final choice of code words for the letters of the alphabet and for the digits was made after hundreds of thousands of comprehension tests involving 31 nationalities. The qualifying feature was the likelihood of a code word being understood in the context of others. For example, football has a higher chance of being understood than foxtrot in isolation, but foxtrot is superior in extended communication.",
"The words are chosen because they are hard to confused with one another.\n\nThe point of the phonetic alphabet is to be able to easily distinguish the first letter of the the word from the first letter of other words.\n\nIf you had it be Apple, Bog, Cat, Dog, Era, Flame, George, Happy, India, Jericho, Kilo, Little, Map, Newton, Ontario, Prairie, Quiet, Roger, Sample, Tornado, Ultra, Victor, Water, Xylophone, York, Zebra then there are going to be some confusion.\n\nObviously things like \"Bog\" and \"Dog\" or \"Cat\" and \"Mat\" can be easily confused especially when you are doing other stuff. Even things like \"Apple\" and \"Sample\" can be confused with enough distractions and/or a poor radio signal.\n\nAnd then there are words like \"George\" and \"Xylophone\" where saying the word doesn't give a precise first letter. Some people spell \"George\" as \"Jorge\" and many don't know how to spell xylophone. \n\nSo they keep it simple and make sure each word has it's own unique sound at the beginning.\n\nAs for how they are chosen? Many of them have been around since codes were first invented and remain due to status quo. Alpha, Beta and Delta are actually names for the equivalent forms of \"A\" \"B\" and \"D\" from the Greek Alphabet. And others have been included because they work better and/or are easier to remember than their predecessors."
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4w50z9 | what is the most probable scenario for worldwide infection of some deadly disease? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4w50z9/eli5_what_is_the_most_probable_scenario_for/ | {
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"A significant international event, for example an Olympics. \nHeld in a place where an outbreak is occurring, Zika doesn't quite fit that bill.",
"There is no probable scenario for worldwide infection of some deadly disease, sorry - no Walking Dead Zombie Plague.\n\nWhen people are exposed to an infection, many of them fight it off. Even a specially engineered bioweapon wouldn't have 100% effectiveness.\n\nWhile there is widespread travel and traveling patients are a good vector for spreading a disease widely, it is not true that everybody travels. As we saw with Avian Flu and SARS, travel restrictions are imposed pretty quickly to block the spread.\n\nYou'd have to have an airborne disease that can cross into many types of animals with a long period until there were symptoms and a short time until the infected person was contagious. Aliens cook this sort of thing up in science fiction novels, but it's not a pathology we see in the real world.",
"As permafrost melts in the arctic, bodies of people and animals infected by bubonic plague or \"new\" types of influenza thaw out and the disease is passed on to humans via animal contact. "
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2he3l6 | why do so many americans believe in god? | As a Norwegian, I think northern Europe is very close culturally to America in so many ways, but here literally no-one, except some of the older generation, believe in god, while I have the impression that religion is a huge part of the lives of so many Americans. Why is that? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2he3l6/eli5_why_do_so_many_americans_believe_in_god/ | {
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"*gets on knee* America was founded by very religious groups of people from England and other parts of Europe called Puritans. They created a country based on religious freedom because they themselves were so religious. A large part of modern Americans come from these families. Their traditions and customs have become the America we know and hate today? ok? *gets up*",
"I think a better question is why ~76% of the population of Norway belong to the Evangelical Lutheran Church of Norway when literally no-one in Norway believes in god.",
"One of the principles that is highly protected in the US is religious freedom. This means that at times there have been large waves of immigrants who have come to the U.S., such as the influx of of Catholics from Ireland, Germany, Italy, and elsewhere in the 1800s.\n\nThe bigger issue, though, is the Cold War. During that time the Soviet Union was a secular state and there was a lot of propaganda that focused on this fact. When you have a person who has learned their morals through religion and you need to paint an entire union of nations as being inferior and immoral it is easy to attack them for their godlessness. This greatly strengthened the power of Christianity in the US. It is from that era that the motto \"In God We Trust\" found its way onto all of the coins and currency of the nation and that the pledge was amended to be \"One Nation, *Under God*\" \n\nThis culture is waning, though. The generation that was most strongly influenced by the effects of the Cold War is aging while there are young adults today who were born after the fall of the Soviet Union. \"No Religion/Athiest/Agnostic\" is the fastest growing religious (or lack thereof) philosophy in the country.",
"everyone who says AMERICA HATES CHANGE isnt right. I mean america was the champion to the freaken internet. America was founded and has always been very tied to Puritan beliefs this is why you dont see much nudity in american media. the folly of your logic is that america is simular to the Scandinavians when in fact they are very different. yes the houses my be similar but the people are very different ",
"* much of America was founded by people specifically looking to practice their religion without gov't interference\n* lack of a state religion mean churches are in competition for members and actively recruit and retain them...in European countries, a state religion came to dominate, and once established, didn't have to try very hard, and became tepid",
"I can't see this thread going badly at all. :^ )",
"America was founded by very religious groups of people, and was were numerous waves of religiously persecuted people came over the centuries.",
"people want magic, not logic.Not just in America, in other religious countries as well.",
"Thanks for the replies! I think I understand the historical aspect, but I still don't get why Americans haven't moved away from religion to the same extent as many (northern) Europeans the last 30-40 years, considering how big of a role science has in modern society, and especially since a lot of the scientific advantages are being made in the US. It's also weird hearing so many people thanking god in public (actors, the president etc). That would be really really strange in these parts! I'd dare to say almost cringeworthy."
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1ih44w | If one calorie, when burned produces enough energy to raise the temp of a litre of water by one degree. If I burn 100 calories, could I boil that same litre? | askscience | http://www.reddit.com/r/askscience/comments/1ih44w/if_one_calorie_when_burned_produces_enough_energy/ | {
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"NOTE: A calorie is not a Calorie (aka, kilocalorie, food calorie). One Calorie (the measurement used for food) is equal to 1,000 calories. So, one calorie would heat one milliliter of water one degree, but one Calorie would heat one liter of water one degree. Having said that...\n\nIt depends on what you mean by boil. You could certainly increase the temperature of the water by 100 degrees. But to cause phase change (liquid - > gas) uses a great deal more energy than to increase the temperature of a substance by one degree.\n\nIF:\nheat of vaporization of water = 2257 J/g = 540 cal/g (which is true)\n\nTHEN:\nIt would take 100 Calories to heat a liter of water by 100 degrees (from 0 to 100 degrees celsius), but it would take 540 Calories to vaporize a liter of 100 degree water.\n\nThis is all assumed to take place in a vacuum, and so, ultimately, the answer to your question is no. 100 Calories are the amount that would be utilized to raise the temperature 100 degrees, but you'd have to use more than that much fuel, due to radiation and convection and conduction drawing the heat out of the water.",
"If burning a Cal would heat a litre of water by one celsious degree, then that means that when we are excercising and we being composed majorly of water we are rising our temperature in the same way?\nI mean, were it not because sweat would we boil in the midst of running lets say an Ultra Marathon?",
"I have a similar question.\n\nIf I drink 1 litre of beer, that's at 4C, my body has to raise the temperature of said beer to 36,7C right?\n\nSo if said beer is low calorie do I actually burn more energy heating the beer than I get from that beer?\n\nSimilarly if you drink really cold water, does that help to burn calories?",
"I'm going to describe this in a simple and theoretical manner because I think it's useful.\n\nIf you were able to not lose any energy and perfectly put 100 calories into one liter of water you could take it from 0 deg C (but still liquid) to 100 deg C. But it would still be liquid, it takes more energy to boil it and turn it into a gas.",
"Also the temperature change of water built into the definition of a calorie is from 0 to 1 degree. Things change a little at different starting temperatures",
"If I remember correctly from my chemistry days, 1 calorie (not food Calorie. 1 food Calorie = 1000 calories) will raise 1mL of water one degree C. \n\nBurning 100 calories will raise 1mL 100 degrees. Burning 100 calories will rais 1L of water approx 0.1 degree C.\n\nIf we are talking food calories (Calories) 1 Calorie will raise 1L of water 1 degree C. Burning 100 Calories will thus raise that 1L 100 degrees C \n\nAs with all good science could someone please check my math?"
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2y5jpg | how can full albums stay up on youtube for months if not years without being taken down, but full movies are taken down almost instantly? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2y5jpg/eli5_how_can_full_albums_stay_up_on_youtube_for/ | {
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"Because the groups which manage the rights for music have got their shit together and negotiated deals with Youtube. GEMA (Germany) is the exception, so most of these albums are blocked in Germany."
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xc3oh | When did the US and other western nations find out about the genocide in Germany? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/xc3oh/when_did_the_us_and_other_western_nations_find/ | {
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"Very early on:\n\n_URL_0_",
"To be fair the genocide took a long time to get rolling. \n\nFirst off, the Germans had to figure out how to kill so many people in an efficient manner. They tried firing squads, gassing with vehicle exhaust and other methods before figuring out to use Cyanide and large warehouse like gas chambers. \n\nThe process started in the 1930's for disabled people and undesirables and the end result was a mega camp like Auschwitz. Built from the ground up specifically to kill people in quantity. History focuses on the Jews which were killed there, rightly so, but it should not be ignored that these camps were often used for political prisoners and POW's from occupied countries which were also killed en mass. \n\nBasically my point is that the genocide wasn't all of a sudden, it was a gradual process that became worse by orders of magnitude. It could be argued that if the US was truly aware of the extent of the program they would have entered the war far earlier. "
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d0il1q | why wet slaps hurt more? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d0il1q/eli5why_wet_slaps_hurt_more/ | {
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"Skin is soft, mushy, and full of lots of little cracks and holes. When you slap someone, a lot of the force from the slap gets cushioned by the skin and dissipated over the larger surface area created by those little uneven surfaces. This happens for both your hand and the slapped person.\n\nWhen your skin is wet, it pulls itself taut to help keep that moisture out. This tightens it out a bit to reduce surface area and makes it slightly less mushy. In addition, the water fills in some of the cracks and holes, making the surface more uniform. This reduces the energy lost and makes the slap hurt more.\n\nIf you wait even longer while wet, like long enough for your hand to get all pruney, the opposite will happen. All of those wrinkles increase surface area and make the skin even mushier, and so the slap will hurt even less.",
"It is surface area. The water fills the gaps in your skin of the hand and surface of the other area. Evenly dissipating the power of the slap onto its target. Creating more efficient energy transfer. \n\nYou ever tried to hit something, swing hard and just not get enough hand on it. Like a volleyball serve where your fingers engage before your palm, it will not go as far because you did not evenly transfer the power.",
"Good god!\nI asked this question on a whim\nI didn't know reddit was waiting for it.",
"the other commenters are mistaken, i think. it’s not a surface area thing, it’s an air cushion thing. the pain of a slap comes from the linear kinetic energy of the slap being transferred to the struck skin, and air lets some of the linear force become transformed into motion in a random direction via turbulence and subsequently into sound and heat. by making an airtight seal, a slap that occurs at a wet palm/skin interface compresses all of the air at once. you can think of it as a wrinkled vs a flat surface striking skin. as the rough surface comes toward the skin, the taller peaks of the surface will be “squishing” the air faster than the troughs, so those areas will experience a sharper rise in pressure. the adjacent troughs will be at a lower pressure and air will flow sideways to equalize this, stealing forward momentum that could otherwise be spent on pain. there’s only so much force behind the slap, and moving air isn’t free. more force spent pushing air sideways means less force pushing meat hard enough to hurt, less force means less pressure. \n\nwell, the why of a wet slap hurting more probably has something to do with the fact that the acceleration is happening quickly. i don’t know why sharper acceleration is more painful, but i’m pretty sure that’s the cause.",
"Its because water is not compressible, for the same reason that water is like concrete when an object hits it from a great height."
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1fspuo | When we look at the processes that happened in the big bang, where exactly do we point our telescopes? | We have the ability to use information from frequency shifts in determining how long ago something happened, but where exactly do we look? | askscience | http://www.reddit.com/r/askscience/comments/1fspuo/when_we_look_at_the_processes_that_happened_in/ | {
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" > where exactly do we point our telescopes?\n\nAny any direction you want. Every single point in the universe was part of the big bang. You just want to look very far away, since light takes time to travel, and thus the further away something is, the further \"into the past\" you're looking.",
"Strangely, you can study the big bang by looking in any direction. It didn't happen in any one particular 'place' as we would normally understand that term. Since space itself was all curled up, it sort of happened everywhere.\n\nWe figured out when the big bang happened essentially by looking at how fast galaxies are moving apart, figuring out how far apart they are, and then just doing the math to determine when they should have all been in the same place.\n\nThe most direct observations of the aftermath of the big bang we have come from looking at the cosmic microwave background radiation. This gives us access to what was going on a few hundred thousand years after the event. To study this background radiation, we have to survey the whole sky. You can read a bit about it [here](_URL_0_)."
]
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[],
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"http://www.scientificamerican.com/article.cfm?id=what-is-the-cosmic-microw"
]
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wauo1 | why does gatorade hydrate you better than water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/wauo1/eli5_why_does_gatorade_hydrate_you_better_than/ | {
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"Gatorade doesn't necessarily hydrate you better than water. What it has that water doesn't is high levels of sodium, which replaces the salt that you sweat out. It also has ingredients that replace lost electrolytes.",
"Because its got what plants crave.",
"Electrolytes, water doesn't have any and in large amounts can actually flush them from your system. Without electrolytes and sodium you get to die a very unpleasant death. Be better to mix water and Gatorade, or even pickle juice, as it's packed with electrolytes and tastes better. ",
"As they have already said, but here is the 5YO version. Your body is like a car battery. You need both water and electrolytes to make your battery work. When you sweat, you lose water, salt and electrolytes. When you drink water you replace the water, but not the electrolytes. Before Gatorade made Orange Bowl champions out of the University of Florida, the coaches would have water, ala Adam Sandler \"Waterboy\" kind of water. \n\nThe water will rehydrate a player, but the salts and electrolytes will still be depleted. If you add enough water, the player would lose a lot of electrolytes, and like you car battery overfilled with water, not have a lot of power. Gatorade adds the electrolytes. Too much so in fact. You are better diluting the Gatorade by half in order to keep the balance correct. "
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9j2npq | What access did women who were not in the nobility have to education and literacy in the 16th century? | Was education mostly a private matter done at home? Was it strictly religious? What types of secular education existed? How would women's acess to these have varied all across Europe going from Ireland to Muscovy and Sweden to the Barbary Coast? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/9j2npq/what_access_did_women_who_were_not_in_the/ | {
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"The short answer is \"It really depends on where, when and who\". The long answer is that (and I admit this is a very broad statement), across the board, women were educated, privately, but not to the standards or expectations of modern day. \n\nMy area of study is Shakespeare and Elizabethan England, which means that my world-view of this time period is, admittedly, quite Euro-centric, so I will speak to those as best I can and leave the other areas for those who know more than me. \n\nThe long answer is that I'm on bedrest from surgery so buckle in:\n\nLt's jump in our handy time machine. Congrats! You're now a 10 year old girl in the mid-16th century England, daughter to a middle-class merchant. So what are your options? According to David Cressey, 90% of the merchant class were literate. We'll say that your family is part of that group. Literacy across the whole of England isn't great, maybe 25%-45%, depending on the area, the year and the social group you're polling, but hey, your family is one of the lucky few! \nSome relevant facts to provide some perspective: \nIn 1533 Thomas More estimated that more than half the population could read English. \nIn 1535, a copy of William Tyndale's new English Bible was ordered to be placed in every parish church. \nTHEN, in 1543, The Act for the Advancement of True Religion restricted the reading of the bible to certain social classes. Women below gentry rank, servants, apprentices and generally poor people were forbidden to read it. Women of the gentry and the nobility were only allowed to read it in private. #feminism, y'all. (But conversely, the fact that they had to pass a law about it implies that there was enough of the general citizenry able to read that it was becoming a subversive issue). \n\nSo anyway, your older brothers go most days to the Grammar school, where they learn Latin, writing, reading and Rhetoric. These schools existed, to, as Peter Mack writes, \"\\[make\\] their pupils wise, pious and eloquent. (12)\". They used a foundation of Latin texts and rhetoric as a means of teaching, with the thought \"that education served to promote religion, moral virtue,wisdom and eloquence, that these qualities were linked and that the training best suited to produce them was a study of classical languages and literature\".(14) (Fun field-of-study-sidenote!: you can basically trace Shakespeare's grammar school education through the use of mythological references in his books, which provide almost, to a T, a cross-index of the required reading materials of the Grammar schools of the time. Neat!) If you were from an affluent merchant family, your brothers might stop after grammar school, or go on to University, law school, an apprenticeship in another trade or, possibly, seminary. \n\nLeach estimates that at the start of Henry's reign England had about 400 schools for a population of 2.25 million, (or one school for every 5,625 people)...later this number would expand when, in 1541, he passed a series of laws that mandated that any Cathedral built would be required to also organize a small school for local boys and provided a government salary of about 20 pounds for the headmaster. \n\nMoving on. Why can't you go with them? Well, you might have, depending on where you lived. If you lived in a very rural town, there are some cases of girls being allowed to attend \"petty school\" (basically, sort of a mishmash of basic foundational education skills like the ABS, 123,s but nothing too in depth) as young children, but everything I could find seems to indicate that by age 10, girls were excluded from this type of school. The thing is that these petty schools were a BIG DEAL. There is a ton of historical evidence that boys and girls from all walks of life were being educated-- books and guides on how to run an effective petty school exist as far back as 1530, and, fun fact, the differing levels of quality in petty schools is one of the reasons why they finally invented a dictionary. The thing is that we just don't know how many people took advantage of these educational opportunities, or whether it just wasn't considered worth recording. \n\nGood news, though! Your dad is a merchant! The rise in the merchant class, meant that for the first time, many people saw the value in educating their daughters in order to preserve the family business. There are several instances of women being left family businesses, so it stands to reason that they were educated enough to run things on a day-to-day basis.\n\nSo how -and what - do you learn? We know that women were usually educated at home, through private tutors or by being sent to the home of a more affluent family friend or relative, where a group of girls would get together and study under one tutor (sort of like an early home-school co-op, if you will). Your education will consist of reading, basic arithmetic (to aid in cooking and household bookkeeping). You'll learn music, dancing and wifely arts like sewing, and if you're really lucky, you might learn a language like French or Italian to make you more appealing to suitors. \n\nMuch of what we know about the education of women comes from process of elimination. One of my favorite weird side-hobbies is looking up old cookbooks of the time, and we have strong proof that, at least by 1618, there was enough of a market for William Lawson and Gervase Markham to publish a series of books and guides on \"housewyferie\": advice on gardening, raising animals, baking and cooking. (If you ever get bored, check them out, some of the recipes are honestly really good). So enough of the Real Housewyfes of London had enough interest (and literary ability) to sell out several runs of these books. \n\nSo were you totally screwed as a woman in the 16th century? No. While it was rare, there are some REALLY COOL examples of women being well-educated. \n\nOne such example is Aphra Behn, a published playwright and poet of the time who was notable in that her writing was well-received enough at the time to be published. She also put out a translation of Aesop's fables, which also indicates multi-lingual talents. \n\nAcross other parts of of the world, interesting things were happening: In Poland, the queen founded an all-girls school, but there isn't much in the historical record to know what was taught. \n\nAccording to the literacy rates that I found (link below), it would seem that our Nordic cousins had far better national averages for both men and women during the period, but I can't speak to that as well as Europe. \n\nOne fun side note: Spain had some CRAZY stuff going on with women's education. There are at least five known instances of women teaching at the University level, and a couple of them even earned their Doctrates in philosophy, and honestly it is a CRIME there there is no Netflix series about a group of badass women teaching college in 16th century Spain. \n\nSara Scalenghe also published a SUPER interesting article about Deaf culture in the 16th century Syria, and it provides some interesting insights on education in that capacity as well. \n\nSo, to sum up: Most education of woman was private and incorporated a great deal of religious education as well, but not necessarily JUST that. Access differed from country to country, but I think it might even be more fair to say that access differed from household to household, as there was no set, standard curriculum for women. However, like I said, my field of study is a very narrow window of time in one specific area of the globe, so while I can share some fun facts that I came across, I really can't answer for other parts of the world as well as some other global scholars might. \n\n\nHope this was at least semi-informative and helpful. \n"
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5h9eks | Did Francis Scott Key show his support for slavery in the Star-Spangled Banner? | So due to all the controversy, though late as it maybe, Colin Kaepernick has decided to sit out the National Anthem of the United States. Now he says that he doesn't want to celebrate a country that persecutes Black People. So I decided to research it, especially after my sociology teacher brought it up, and I found something interesting. It's about this passage.
> And where is that band who so vauntingly swore,
> That the havoc of war and the battle’s confusion
> A home and a Country should leave us no more?
> **Their blood has wash’d out their foul footstep’s pollution.**
> **No refuge could save the hireling and slave**
> From the terror of flight or the gloom of the grave,
> And the star-spangled banner in triumph doth wave
> O’er the land of the free and the home of the brave.
More specifically the part in bold, I wanted to know if the original author, Francis Scott Key, intended it to be a pro-slavery verse and if he was really a racist himself. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5h9eks/did_francis_scott_key_show_his_support_for/ | {
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"Hello there! Here is a [.pdf](_URL_2_) containing the full version of the poem.\nThe portion you have in bold is one of the references to slavery, as well as the following:\n\n\"O thus be it ever when freemen shall stand.\"\n\nOutside of writing the Star Spangled Banner, Key was one of the founders of the American Colonization Society (ACS), an organisation whose goal was to aid free blacks that wanted to go to Africa. Other founders include individuals such as James Monroe and Andrew Jackson. both of which owned slaves. There were also abolitionists such as Henry Clay, author of the Missouri Compromise, that supported the ACS. People like Frederick Douglass would later be vehemently opposed to colonization, [saying](_URL_0_):\n\n\"In view of this proposition, we would respectfully suggest to the assembled wisdom of the nation, that it might be well to ascertain the number of free colored people who will be likely to need the assistance of government to help them out of this country to Liberia, or elsewhere, beyond the limits of these United States—since this course might save any embarrassment which would result from an appropriation more than commensurate to the numbers who might be disposed to leave this, our own country, for one we know not of. We are of the opinion that the free colored people generally mean to live in America, and not in Africa; and to appropriate a large sum for our removal, would merely be a waste of the public money. We do not mean to go to Liberia. Our minds are made up to live here if we can, or die here if we must; so every attempt to remove us will be, as it ought to be, labor lost. Here we are, and here we shall remain. While our brethren are in bondage on these shores, it is idle to think of inducing any considerable number of the free colored people to quit this for a foreign land.\"\n\nVariations of this plan have been advocated by a wide spectrum of people including Marcus Garvey, Malcolm X, and the KKK. \n\nWhether or not he supported the perpetuation of slavery as a practice is not explicitly discussed in any of the letters that I have read by him. The ACS is, by contemporary standards, inherently racist and essentially the precursor to segregation (By acknowledging that whites and blacks were best not to mix). Using contemporary standards to evaluate historical figures is troublesome as many of these people believed that they were acting in the best interests of slaves. Key came from a slaveholding family and owned several himself, yet is compared to people like Jefferson as a gentle slave owner. Encyclopedia Brittanica claims he was also an early and ardent proponent for ending the slave trade, though I could not find anything (in my brief search) corroborating this.\n\nFor example, Key [writes](_URL_1_):\n\n\"Dr Ayres says he is making preparations for a school. He means to adopt in some measure the plan of Mr. Johnson at Regent’s Town, & keep the captured Africans & the boys together. - He has put them for the present under the charge of Lott Carey. - The young man you speak of will be eminently useful, and I trust the Lord will preserve him.\"\n\nGauging the benevolence of someone's actions is based on opinion, so you would have to declare for yourself whether you think his actions reflect someone that is racist. You will not find a historiographic consensus on the subject, especially with how political the debate has become recently. \n\nBiographical information from Gilder Lehrman Institute of American History, Encyclopedia Brittanica sections on Francis Scott Key, Henry Clay, and the American Colonization Society,\n\n\n"
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5e67ut | Are we in a final period of a little ice age? | So, a guy told me last night that the reason why the global warming is happening is that we're in a little ice age that is just ending and that's why the temperature increases. Is he right or wrong? Thank you for the answer. | askscience | https://www.reddit.com/r/askscience/comments/5e67ut/are_we_in_a_final_period_of_a_little_ice_age/ | {
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"It's actually the opposite. We're at the tail end of an [Interglacial Period](_URL_1_), a warm time between Ice Ages. All of human civilization has existed within this interglacial period known as the [Holocene](_URL_0_). The next big Ice Age was supposed to begin [around the year 3500ish](_URL_2_), but global warming will probably prevent that. The climate should actually be cooling going forward, and that's not what we're seeing.\n\nThere *was* a \"[Little Ice Age](_URL_3_)\" from about the 1300s to the 1800s, which was a period of slightly cooler winters and increased ice growth (nowhere near a true Ice Age, where glaciers dominated the landscape). But, as you can see from the [associated graph](_URL_3_#/media/File:2000_Year_Temperature_Comparison.png), we've been nowhere near the temperatures seen then for the last 150 years, but we are seeing temperatures much warmer than warm period prior to this \"little ice age\".",
"The aforementioned Little Ice Age (by u/functor7) reached its glacial maximum around 1850 throughout the European Alps, and since then the climate has been warming. There is a blip in the records around 1920's when we have an extreme cold event of approx. five years but apart from that we have seen a general increase in atmospheric temperatures. \n\nIn the European Alps this is incredibly clear when looking at the recent (last 160 years) glacial history; between 1850 and 1900 there is a small amount of glacial fluctuation but most glaciers stayed near their 1850 LIA Maximum. However, since 1920 we can see a rapid reduction in glacier volume with many glaciers retreating several Km's and some melting away altogether. Further to this the summer of 2014 resulted in the biggest loss of glacial ice (at least in the Austrian Alps) that has been seen since the 21st Century. \n\nSo to answer you question: No we are not currently in a Little Ice Age, and have not been for the last 160 years. Global Warming is happening at a rate never before seen in the geological record and 98% of the scientific community agrees that this is a direct result of anthropogenically forced climate change."
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"https://en.wikipedia.org/wiki/Little_Ice_Age#/media/File:2000_Year_Temperature_Comparison.png"... | |
ccgof1 | why do a lot of out of tune people singing together sound not out of tune? or at least not as out of tune as compared to if they all sang as individuals. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ccgof1/eli5_why_do_a_lot_of_out_of_tune_people_singing/ | {
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"Your brain is good at understanding patterns, and what things are \"supposed to be.\" If one person does something wrong, your brain says \"that's wrong!\" but if multiple people are doing different things wrong then your brain can pick out the \"right\" parts of the singing and focus on that. If everyone sang something completely wrong then it would be equally difficult to listen to.",
"Also it is much easier to sing in tune when you have a lot of other people singing with you. This is actually how I learned to sing, and I still can't sing most songs on my own, but I sound fucking great at those group songs. \nSomeone else can provide explain harmonizing in more detail. I think that's the concept you're experiencing."
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1sxoof | Anybody an expert in Australian history (1810 - 1820)? | Hi all, I have a few specific questions about how things were in Australia in the early 19th century.
1. Was it common for ticket-of-leave men to work alongside full convicts?
2. Was it common in this time for people to want to go back to the UK?
3. How intense was the military presence in the colonies? Was there a police force? How free was a ticket-of-leave person to go about their lives undisturbed?
4. Some people I've been trying to track records of appear to have wives and children, but then are convicted again later and appear never to return to their families. Was this common? What happened to the families of people who were re-convicted after being freed? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1sxoof/anybody_an_expert_in_australian_history_1810_1820/ | {
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"I've covered some of this information [at length previously](_URL_0_).\n\nI'll summarise the relevant points here:\n\n1) Quite common.\n\n2) Of course!\n\n3) Lots of military. The military doubled as a police force until an actual police force was started. Quite.\n\n4) Don't know, sorry.\n"
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8hz8ig | what triggered the us to pull out of the iran nuclear deal? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8hz8ig/eli5_what_triggered_the_us_to_pull_out_of_the/ | {
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"Trigger #2 for 45 was that Obama admin negotiated it and he wishes to destroy everything Obama."
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dqkcb4 | How do Space Probes travel differently? | What is the mechanism behind Space Probes like Voyager 1 being sent to fly-by the planets and off out into interstellar, compared with probes with Cassini which are meant to be captured in a planet's orbit to study that specific planet?
Are they sent at different velocities or are they sent on a trajectory closer to the planet in order to be captured by its gravity?
Apologies for the inane questions. | askscience | https://www.reddit.com/r/askscience/comments/dqkcb4/how_do_space_probes_travel_differently/ | {
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"A planet's gravity can't capture a satellite by itself. You need at least two bodies (plus your satellite) to do something like that. We know this can happen, because some planets have moons which appear to be captured asteroids.\n\nBut in general, it's very rare because it requires a very specific alignment of the bodies. So in practice, if we want a probe to be captured, we fire its rocket engines on arrival in order to accelerate or decelerate to a speed that puts it on an appropriate orbit around the planet it's visiting.\n\nMany proves, including Voyager, use flybys to gain speed, by swinging around a planet and stealing a tiny bit of its momentum. The planet slows down imperceptibly, while the much lower mass of the probe allows it to gain a substantial amount of speed.",
"Trajectory is important. To simplify things, if a probe flies \"behind\" the planet it'll get a speed boost, if it flies \"in front\" it'll get a speed drop, and if it flies over or under the poles it'll get an inclination change.\n\nTo actually enter orbit round a planet, a space probe needs to use its rocket engine, which means it needs to carry propellant for that, which makes it heavier. The Voyager spacecraft weighed 773 kg and carried only enough fuel for small manouvres and orientation. (By getting the initial launch from Earth just right, it doesn't take much fuel on the probe to fine-tune the gravity assists). New Horizons was even lighter. By contrast Cassini weighed over 5 1/2 tonnes, Juno around 3 1/2."
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8wbi27 | why is it that in radio frequencies, the lower the frequency the further range you get but less bandwidth? | Was reading bout 5ghz vs 2.4 GHz WiFi . Basically why is attenuation proportional to frequency? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8wbi27/eli5_why_is_it_that_in_radio_frequencies_the/ | {
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"Think of a 5GHz signal as a fully loaded car, and a 2.4GHz signal as a fully loaded semi. \n\nWhich do you think is easier to stop?\n\nA 5 GHz signal is tiny, and cannot pierce through many solid materials like buildings or mountains. They can even be disrupted by rain.\n\nIn contrast a 2.4GHz signal is bigger in comparison and will pierce through more substances. \n\nAs for information sending, imagine the lower bandwidth signal is someone talking really slowly. You'll get the information, but it will take a while.\n\nThe higher the frequency the faster the talking.\n\nThis is how I understand it.\n\nSource: Radio Technician\n\nEdit: The semi vs car analogy wasn't about the data transfer rates but rather about how hard it is to stop something big. I realize in retrospect I should have used a different analogy. \nI'm leaving it up because it still makes sense to me.\nTake it as you will.",
"The ~~bandwidth~~ throughput reason is pretty straightforward: If you talk faster, you can have longer conversations in the same timespan. Higher frequency - > higher ~~bandwidth~~ throughput.\n\nAs for range, it's similar to driving a car: The faster you drive, the more noticable the windresistance becomes. High frequency radiation is dampened stronger than low frequency radiation, thus low frequency has a longer range.\n\nEdit: As has been pointed out, throughput is the word for data transfer rates. And according to u/TheDapperYank symbol-times are standardised and constant, so my first analogy is based on faulty assumptions anyway.",
"High frequency waves are more easily absorbed by materials. But just because 2.4GHz will go further doesn't mean you will get a better real life data rate due to many more devices being on the 2.4GHz band, shitty access points not choosing a non-overlapping channel, Bluetooth interference, USB 3.0 interference, etc.",
"Radio is a kind of light (just way lower frequency than red).\n\nRadio travels at the speed of light - no matter what frequency. High frequencies can carry more information in a given time because there there is more \"room\" for changes to be detected.\n\nThink of riding in a car over a bridge with the regular \"thump-thump .... thump-thump ... \" sounds. The only way to communicate information is to suppress (0) or amplify (1) these \"thumps\" or \"peaks in the radio wave\". The more \"thumps per second\" you have the more 1s or 0s you can transmit. ( [_URL_0_](_URL_1_) )\n\nAs for why high frequencies don't travel as far - it comes down to dispersion. Make waves in a lake or a bathtub. Slower waves are easier to see (peaks and troughs). Faster oscillating waves are easier to see closer to the sources ... but as you look further from the sources these waves become \"smooched\" together. You lose the \"thump-thump\" type features needed to convey information.\n\nNot a 100 & #37; accurate explanation what's going on at the physics level - but this is the start I give my kids.\n\nNote: Some answers given talk about materials absorbing certain radio frequencies - which is correct but the effect you're describing in your question will also apply in empty space without any materials messing things up.",
"A better lay definition would be that within a specific distance the intervening material will interact with a wave more often the shorter the wavelength is. You have to adjust for specific sizes of material having a stronger than normal impact if they match the wavelength of the transmission, but that's the general rule.\n\nA good (not perfect) visualization would be to scatter balls across a pool table. Then to simulate low frequency trace an s curve across the table with a stick and see how many balls you hit. Then zig zag back and forth 10 times (at the same amplitude) and see how many you hit to simulate high frequency. On top of this just one set of pool balls scattered on the table might be like passing through air, while 20 sets more like a cinder-block wall.",
"Bandwidth isn't the term you want. Throughput or capacity is the term you want. \n\nThis is going to be more of an eli13\n\nBandwidth is the span of frequency you're using, and it's functionally frequency independent. \n\nHow RF signals work is that they are generated at the frequency of the bandwidth you are interested in. So a 20Mhz wide signal is generated from 0-20Mhz. This is called the \"Baseband\". What happens next is the Baseband signal will get sent to the radio which will basically just shift it up to whatever your transmission frequency is. For wifi that's either 2.4Ghz or 5Ghz.\n\nNow as for why you TEND to get higher throughput at higher frequencies is mostly due to RF noise and interference. WiFi specifically uses a technique called Carrier Sense Multiple Access with Collision Avoidance. In short this means that all the devices that want to transmit will listen and wait until they don't hear anyone else transmitting before trying to transmit their data. So if you have lots of RF noise then the devices will refrain from transmitting till they think the RF environment is clear. That and noise will impact how efficient/dense the data being sent is. \n\nWiFi uses a waveform called Orthogonal Frequency Division Multiplexing (OFDM) where the spectrum is subdivided into smaller and smaller chunks of time and frequency that do not overlap, until you get to individual symbols. These symbols are functionally a sine wave, and based on and amplitude and phase of the individual sinewaves it represents a series of 1's and 0's. If the RF environment is clean then you can pack more 1's and 0's into a single sine wave.\n\nNow, for pathloss. RF through freespace is NOT actually attenuated. It just acts like it is because the RF energy is being spread out over the surface of an ever increase sphere the further away you are from the source. The reason why lower frequency (larger wavelength) signals have less pathloss because the aperture of an equivalently optimal antenna will be significantly larger, touching more surface area of the sphere of RF energy.\n\nDoubling the frequency is equivalent to doubling the distance from a pathloss perspective.\n\nSource: am RF/Telecommunications Engineer\n\n**edit:** spelling"
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bve6fq | how does cold transfer if it's just the absence of heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bve6fq/eli5_how_does_cold_transfer_if_its_just_the/ | {
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"Cold sucks the heat out of other things. If you have a cold thing and a hot thing and put them together the heat will transfer to the cooler part until they both reach the same temperature as their surroundings.",
"Others have covered thermodynamics. There is a slight/not-really-exception to this which is convection. Warm gasses rise causing cooler gasses to fall, meaning in a tall room, the cold comes down. Also if you open a door on a windy day, physically cold air may blow in and replace your warm air. In a closed system the warm air would give its heat to the cold air in time, but this is why it annoys me that \"smart\" people poke fun at the commonly said \"you're letting the cold in\". You can absolutely let cold air in.\n\n/end rant.",
"Think of heat as a bunch of super bouncy balls. If you have big box and you pour a lot of these balls in one end of it, then they are going to be bouncing into each other and on the walls. This is the hot end of the box. \n\nIn the other end of the box there are no balls. This is the cold end of the box.\n\nNow, every time a ball bounces towards the hot end it's more likely to bounce of another ball, because there's loads of them. \n\nBut if it bounces towards the cold end it's got more free space and is less likely to bounce of another ball.\n\nThis way balls migrate over towards the cold end until the balls are pretty much evened out across the box. The cold end has become hotter and the hot end has become colder.\n\nBut the emptyness(cold) hasn't moved to the hot end, it's just that some bouncyness has moved from the hot end to the cold side so now the hot end is less hot (or less full of bouncy balls)",
"Cold doesn’t transfer, as in cold moving from one object to another. As you said cold is the absence of heat, so a colder space tends to attract heat. The cold isn’t moving into a new area, heat is being sucked away from said area into the colder space. Think of it like oxygen in a vacuum where the barrier between the two gets broken (window in space ship breaks. The vacuum isn’t moving into the oxygenated area, the oxygen is being pulled into the vacuum.",
"It was explained to me this way. There is no such thing as cold, it’s simply less heat, not necessarily the absence of heat. We can’t measure cold, we can measure heat. So even though something feels cold to the touch, it’s simply far less hot than your hand and therefore it transfers the heat from your hand faster than your hand can transfer the heat from the “cold” item. I’m no scientist and I’m sure others can explain better, but it helped me when explained that way.",
"Cold doesn't really transfer. The second law of thermodynamics states that heat transfer only occurs from hot to cold. In other words, heat will never move from a cold to a hot object. Heat will be transferred from a hot region to a cold region until there is no temperature difference.",
"Cold doesn't transfer but the difference in temperature between a cold substance and a hot one increases the rate at which the hot substance loses heat to the cold substance.",
"Cold do not travel as it is not a thing. It is heat that travel in the other direction. It is heat that travel from the warmer object to the colder object. The result that the warmer object the a colder and the colder object get warmer.\n\nThe transfer is exact the same as when heat is transferred. There is not fundamental difference between when it is warmer outside and it hear up a house compared to when it is colder outside and it cool down your house. \n\nThere is a practical difference and that is that you can generate heat by burning fuel or using electricity. Covering heat to other energy is a lot harder hand you need a temperature difference to do that. So it is a lot easier to warm stuff upp then to cool then down."
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1gbyp6 | Why use cDNA rather than mRNA? | Why is it that labs use cDNA when investigating genes? What is the advantage over mRNA? Is it possible to use mRNA instead? If cDNA is patentable, which it seems that it is after the recent ruling, could mRNA be used as a substitute? | askscience | http://www.reddit.com/r/askscience/comments/1gbyp6/why_use_cdna_rather_than_mrna/ | {
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"The lab I worked in was using cDNA for a few reasons. We were interested in sequencing mRNA, and the only reasonable way to do it is through cDNA. [PCR](_URL_0_) works on cDNA, high-throughput sequencing works on it in the normal way, and DNA is much more stable than RNA.\n\ncDNA is also useful if you have a protein you want a prokaryote to synthesize, since they don't have the machinery to handle introns, but cDNA has the introns removed.\n\nI don't know why you'd necessarily prefer it for doing the kinds of testing they'd do for BRCA though.",
"CDNA lasts a long time ... rna is readily degraded ... that's the biggest reason.",
"mRNA isbrqpidly degraded due to the differences in the chemical structure. The 2' hydroxyl group on the ribosr sugar enables mRNA to autocatalyze its own destruction via nucleophilic attack. ",
"cDNA is way more stable, and you can amplify it via subcloning or PCR.",
"RNAases are everywhere, literally. They'd be happy to chew up any RNA lying around. ",
"Mainly because PCR works by amplifying DNA...not RNA as it has several steps that require primers to bind complementary strands...and single stranded RNA does not work in this application",
"You can't clone mRNA into a vector.\n\nA vector is circular synthetic piece of dsDNA that is capable of self-replicating (origin of replication), has selective markers (antibiotic resistance genes) and a multiple cloning site which allows insertions of genes of interests (though very few people do traditional cloning nowadays most use Gateway or SLIC cloning). Molecular cloning is basically cutting and pasting your genes of interest into a suitable vector. You can then study the shit out of your genes of interest and do whatever you want with them in an extremely controlled environment:\n\n1. You can transform your genes into a suitable host (E.coli, insect cells, mammalian cells, yeasts) to generate tons of your gene product in the form of recombinant protein. You can then purify these protein, crystalize them to study their molecular structure using x ray crystallography or make antibodies against these proteins.\n\n2. You can screen for proteins that interact with your gene product (yeast 2 hybrid). Similarly you can search for specific DNA sequences that your gene product interacts with (if your gene encodes for a transcription factor or chromatin-associated protein). You can also look for RNAs that interact with your gene (yeast 3 hybrid).\n\n3. You can transform your gene into a genetically knocked-out organism to see if the mutant is restored to wild type phenotype. \n\nReally, once you have cloned your gene, the sky is the limit as to what you can do with it.\n\nNow mRNA on the other hand is an entirely different beast. mRNAs are messages that the nucleus send out into the cytoplasm to guide the translation of functional proteins which are essential for the survival of the cell and in turn, the entire organism, as proteins are infinitely diverse in biochemical activity unlike nucleic acids and the constant turnover and synthesis of proteins keep the cell in tip top shape (until the cell burns out on its telomeres but that is a totally different story).\n\nmRNAs are mainly used to study post-transcriptional regulation and modifications. As a young mRNAs matures, it go through 5' capping, intron splicing and addition of a poly-A tail to its 3' end and also the addition of a flurry of RNA-binding proteins that help to guide it out of the nucleus. These modifications are extremely complex and involve many different proteins and enzymes and many diseases are caused by a defect in the regulation of mRNA post transcriptional modificaiton.\n\n"
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4pfae1 | why is ups suddenly transferring so many packages to usps thus causing delays? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4pfae1/eli5_why_is_ups_suddenly_transferring_so_many/ | {
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"It's cheaper. The USPS has to deliver to every house. The government requires them to do that. UPS is a for profit company that doesn't have to follow the government's rules. They don't have to deliver to everyone themselves. It is expensive to send out a truck, so they try to make the truck to as many deliveries as possible. If your house is far out of the way, or there are no deliveries being made nearby, it's much cheaper to just pass it to USPS than send out a truck to make just a few deliveries.\n\nBut no, I don't know what specifically made them do it so much more frequently now."
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7i5qv4 | why is the lucas number superior to the fibonacci sequence in terms of calculating the golden ratio? | I just don't see the difference. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7i5qv4/eli5why_is_the_lucas_number_superior_to_the/ | {
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"You can get an approximation (estimate, if you prefer) of the golden ratio from lucas/fibonacci numbers by taking one element from the sequence, then dividing it by the previous element. So, for fibonacci numbers (1, 1, 2, 3, 5, 8, 13, 21, ...), your approximations are 1/1, 2/1, 3/2, 5/3, 8/5, 13/8, ... and for Lucas numbers (2, 1, 3, 4, 7, 11, 18, ...) they're 1/2, 3/1, 4/3, 7/4, 11/7, 18/11, ...\n\nBecause both of these are integer sequences, and the golden ratio is irrational, you can never get the exact value. However, the further along you are in either sequence, the better the approximation.\n\nSo... how good are these approximations? That's where the Lucas numbers are \"superior\" to the fibonacci sequence: After a frankly wonky start (because lucas numbers start weird, with the first term being bigger than the second), if you take the same number of steps (that is, for both sequences dividing the 11th element by the 10th element, or dividing the 28th element by the 27th element, or whatever else), then doing that same amount of work using the Lucas numbers gets you an approximation that's closer to the true value than you'd get with Fibonacci numbers.",
"A given Lucas number is twice the average of two Fibonacci numbers, those being the one just before and just after the ordinal position of the number in question. \n\nI.e. L(n) = F(n-1) + F(n+1).\n\nSo it's going to be a slightly smoother approximation that will be slightly closer to the golden ratio at any given time, but inconsequentially so. ",
"First lets define some things so that it doesn't get too messy. \nLet A := 1+sqrt(5) and B := 1-sqrt(5)\n\nThe Fibonacci and Lucas numbers can be defined as such: \nF_n = ( A^n - B^n ) / ( sqrt(5) \\* 2^n ) \nL_n = ( A^n + B^n ) / 2^n\n\nDividing the consecutive numbers by eachother we get the following ratios: \nF\\_(n+1)/F\\_n = 1/2 \\* ( A^(n+1) - B^(n+1) ) / ( A^n - B^n ) \nL\\_(n+1)/L\\_n = 1/2 \\* ( A^(n+1) + B^(n+1) ) / ( A^n + B^n )\n\nYou can rewrite this as: \nF\\_(n+1)/F\\_n = 1/2 * [A / ( 1-(B/A)^n ) - B / ( 1-(A/B)^n )] \nL\\_(n+1)/L\\_n = 1/2 * [A / ( 1+(B/A)^n ) + B / ( 1+(A/B)^n )]\n\nThese two are almost identical since B will be negative and as such the sign of B^n will flip for each step and both of these will converge to 1/2 * (A/1 ± B/∞) = A/2 as n goes towards infinity and they converge equally fast.",
"It cheats.\n\nLucas cheats because it's opening ratio of 2:1 is closer to Phi than Fibonacci's opening ratio of 1:1. Not only that, but Lucas's first two sequence numbers are simply Fibonacci's second two sequence numbers backwards.\n\nAlmost any starting pair of positive integers added in sequence like Fibonacci can reach Phi. A 9, 3... sequence reaches 4 digits of Phi (1.618) at the 11th step, same as Fibonacci."
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7wuj6r | This Week's Theme: Law | AskHistorians | https://www.reddit.com/r/AskHistorians/search?q=flair%3ALaw&restrict_sr=on&sort=new&t=all | {
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"Law has a bit of a reputation as being dry, but after completing a 4,000 word essay I found it can be very interesting in a historical perspective. I look forwards to the questions."
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1m3kzi | Is it bad to drink milk when you have a cold? | askscience | http://www.reddit.com/r/askscience/comments/1m3kzi/is_it_bad_to_drink_milk_when_you_have_a_cold/ | {
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"We conclude that no statistically significant overall association can be detected between milk and dairy product intake and symptoms of mucus production in healthy adults, either asymptomatic or symptomatic, with rhinovirus infection.\n\n_URL_0_",
"Apparently, in some cases, depending on the milk and the person, there is a pathway for milk to affect mucus production.\n\n_URL_0_\n\nDisclaimer: this is not my field.",
"As a biochemist and microbiologist, I think that increased mucus production is generally a good thing in the initial stages of a respiratory infection because it helps to flush out the infectious organism, and thus reduce the severity of the infection. In fact, the mucus stimulating properties of milk are probably important for calves health. In my own experience, whole milk is more effective as an expectorant than skim or 2%.",
"This is not intended to be anecdotal, but to inform about potential incorrect diagnoses that actually can be related to milk. While these effects are rare, I believe they relate to the topic at hand.\n\nAbout a year ago, our six year old daughter got sick and began coughing. It was a normal cold, but the cough persisted well after the virus cleared up. As it was a mild cough, we unfortunately did not see a doctor for some time. When we did eventually have her checked out by a GP, he incorrectly diagnosed her as having bronchitis, but he suggested additional testing. We found out, after following his advice, that her coughing was the result of a mild milk allergy. We had never made this association ourselves because of how prevalent dairy products were in her diet. Cutting these out of her diet had immediately results. \n\nFor the uninformed, a milk allergy is distinctly different from lactose intolerance. She has an adverse immune reaction to one of the proteins in milk, and as such reacts even to \"lactose\" free products that contain milk proteins. \n\n_URL_0_"
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1ccvis | Can gases and liquids be placed under negative pressure? Can these phases exist in a state of tension like the solid phase? | askscience | http://www.reddit.com/r/askscience/comments/1ccvis/can_gases_and_liquids_be_placed_under_negative/ | {
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"I can't seem to find it right now, but I remember reading a paper about a group putting water under tension. With liquids, you have some intermolecular forces to give you tension, but I can't remember if it was possible to do so in equilibrium.\n\nedit: So your answer is yes for liquids. For gases, I suspect you're going to have to cool them down quite a lot, and I'm not sure if anyone has measured anything like that.",
"Yes, negative pressure can exist and is used in the [transpiration pull](_URL_0_) of trees. It is necessary in order to create enough suction for water to climb higher than the ten meters that it rises in a pure vacuum."
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4wrs4t | why does a circuit require a neutral? why is it classified as 0v but has 230v traveling through it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4wrs4t/eli5_why_does_a_circuit_require_a_neutral_why_is/ | {
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"Voltage is a difference in energy levels. There's no such thing as 230V without having some sort of reference whether that's a neutral pin of a power supply or ground.",
"Hey, so your question is worded a bit incorrectly because voltage doesn't exactly work that way. But that's why you asked the question, to find out how it does work!\n\n.\n\nSo to answer your first question: Why do circuits require a neutral. The answer is, they don't. Think of a simple 1.5 Volt AA battery. It has a positive end and negative end. This means the positive side is 1.5 volts higher than the negative side.\n\n.\n\nDoes this mean that the positive side is 1.5V and the negative side is 0V? Not exactly. An analogy we can use is to pretend that instead of voltage, we are talking about height. Let's replace our 1.5V battery (chemical/electrical potential energy) with a 1.5m cliff (gravitational potential energy).\n\n.\n\nWe know that the height of the cliff is 1.5m, but does that mean the bottom of the cliff is at 0m? Maybe, if you define the base of the cliff to be 0m. you could also define the top of the cliff to be 0m, which makes the bottom of the cliff -1.5m.\n\n.\n\nIn this simple battery system, there is no such a thing as neutral. Just a positive reference point and a negative one. So basically, the answer to your first question is, circuits don't require a neutral.\n\n.\n\nOf course the obvious next question is, well why do we have neutrals then? Or what are neutrals?\n\n.\n\nWhat you're probably thinking of is your electrical outlets at home that you plug things into. You'll notice there are three holes, the two 'eyes' on top and the mouth on the bottom. The two 'eyes' correspond to positive voltage and neutral, and the mouth corresponds to ground. (Simplified for ELI5 purposes since AC current in your house is a bit more complicated than that).\n\n.\n\nIn this case, all of the appliances in our house share the same neutral (it all connects back to the power panel in your home). So the neutral acts as a reference. This is like building a whole bunch of cliffs that all have a bottom at the same height, which you define at zero, so you can measure the heights with respect to that zero. (Again, a bit simplified since AC is a bit more complicated than that.)\n\n.\n\nNow, even though we are using the neutral for most of our household plugs, we don't HAVE to. What if we needed a bigger voltage drop? Well, in addition to the 'positive' height of 120V, our AC home system also has a -120V height. What this means is if we have a special appliance that needs 240V (for example, a clothes dryer or an electric hot water heater), We can set up our plug so that one 'eye' connects to +120 and the other connects to -120, giving us a total voltage drop of 240V.\n\n.\n\nOkay, as for your second question, why is the neutral classified as 0V but has 230V running through it, we can see that this question doesn't quite make sense. Voltage measures electrical potential (aka \"height\"), so the neutral doesn't have voltage running through it just like you can't have meters or feet falling off a cliff.\n\n.\n\nSo what is running through your wires? Electric current. Think of it as water falling off your 120m cliff. The energy of the water powers a turbine below using the energy from falling from the top of the cliff to the bottom. Your TV or computer or lights are powered by electrons \"falling\" from 120V down to 0V (your neutral) or even -120V as discussed above."
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50bje2 | Can I have help with a derivation of the Lorentz transforms? | I'm working my way through [this short paper](_URL_0_) after seeing that [PBS spacetime video about it](_URL_1_).
It's a way to derive the Lorentz transforms using only three assumptions: 1) Transformation laws must respect inertia 2) Transformation laws must respect relativity of time and space 3) Transformation laws must form a group structure (i.e. intermediate transformations mustn't affect the end result)
The process seems quite simple, but I have a few hangups:
**(Q1)** Equations 1) and 2) claim that in order to preserve inertia (i.e. straight lines map to straight lines in spacetime), we must do a linear transformation. I can see that linear transformations are sufficient (because it works), but are they necessary? How do you prove that there doesn't exist a non-linear transformation that will preserve inertia? I get the feeling that this is comes straight out of linear algebra- but I don't know where to look.
**(Q2)** Why is case iii (given after eqn 25) physically uninteresting? It looks like you can get the transformation x' = x, x0' = x0 + Bx. In other words, time can flow at different rates in different locations. How is that uninteresting? Why should I toss it out?
**(Q3)** Just after eqn 32) we decide that alpha has to be greater than zero. It's argued that if alpha was negative, 30) would represent a rotation matrix in ct and x spacetime which is unphysical. I'm not convinced. Why is this unphysical? It looks like this kind of transformation can allow for situations where time flows in opposite directions between certain observers... but why should I rule out that possibility? It seems like we're assuming something here that isn't included in the 3 axioms at the start.
**(Q4)** When all is said and done, how do we get 34)?
One more question about this topic in general:
**(Q5)** the PBS spacetime video mentions that the Gallilean transformations are a special case of the Lorentz transformations where c = infinity. I can't see this. According to 35) and 36), as we take the limit c - > infinity, then A - > 1 and C' - > 0. But then 33) is just the identity matrix, and I don't see the Gallilean transformations anywhere.
Anyways, I think it's really cool that a philosopher could sit in an armchair, make some sensible assumptions on how the universe works, and come up with the Lorentz transforms :-)
Please don't feel you have to answer everything ... I'd just appreciate any help :-) | askscience | https://www.reddit.com/r/askscience/comments/50bje2/can_i_have_help_with_a_derivation_of_the_lorentz/ | {
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"For Q3, Lorentz boosts are hyperbolic rotations which mix space and time coordinates. The space components and time components in the Minkowski metric come with opposite signs, if this were not the case, there would be no causality. Any set of two events could happen in either order with a choice of reference frame, which means that one cannot cause the other.\n\nFor Q5, consider a boost in the x-direction:\n\nx*_0_*' = γ(x*_0_* - βx*_1_*)\n\nx*_1_*' = γ(x*_1_* - βx*_0_*)\n\nx*_2_*' = x*_2_*\n\nx*_3_*' = x*_3_*.\n\nIf you take c to infinity sufficiently slowly that 1/c^(2) ~ 0, but 1/c is not that small, you recover the Galilean transformations:\n\nx*_0_*' = x*_0_*\n\nx*_1_*' = x*_1_* - βx*_0_*\n\nx*_2_*' = x*_2_*\n\nx*_3_*' = x*_3_*.",
"Q1) I think the best way for you to understand this point is to try a non-linear transformation [that is, a transformation where the coordinates (x^{0'}, x^') are related to (x^0)^n and (x)^n, for n different from 1], and see that, inevitably, if the unprimed coordinates describe a straight line, the primed coordinates won't. Intuitively, when you apply a linear transformation onto something you can rotate it, stretch it, shift it, but never curve it. This is not the case if the transformation is non-linear.\n\nQ2) The relations x' = x ; x0' = x0 + Bx don't imply that time passes differently in both frames of reference. Imagine a particle moving at constant speed S times v [see Eq. (3)] in the unprimed frame, where S is a dimensionless number smaller than one. Basically, the particle moves at a fraction of v. Then x = Svt = Sx0. Therefore, x0' = x0(1 + BS). This is simply a shift in time: if x0*BS = T, then the instant x0' = x0 + T. Remember that these are the coordinates of an event, so they all represent fixed numbers, not the trajectory per se.\n\nQ3) See, the case studied in the article is a specific type of Lorentz transform called a boost. Other types are rotations, and rotations with a boost. Anyway, the name \"boost\" is because the transformation always relates a frame of reference O with another O' that is moving at a certain speed v relative to O (See Fig. 1). So whenever you apply the transformation, you \"boost\" reference frame O' with respect to O; you \"give it\" a speed v. Now, what happens if you give it two boosts? You give it a speed 2v. N boosts? You give it N*v. Now, consider what we already know: if the speed is small enough (not at all close to the speed of light) we the correct transformation is the Galilean transformation [Eqs. (26) and (27)]. If you boost N times using those, you \"give\" the frame of reference O' a speed N*C, which should be correct if N*C is much smaller than the speed of light. Now, is this possible if alpha < 0 and the operation is a rotation? No, because a rotation is cyclical, meaning that if you rotate enough you come back to the beginning (360 degrees). In other words, you may apply the transformation N times and suddenly find that x' = x and x0' = x0, which makes no sense for a boost!\n\nQ4) Use the coordinates x and x0 to measure the trajectory of the reference frame O' as observed from O. If O' moves at a speed w relative to O, then x = w*t = (w/c)x0. From O', x0' = 0 and x' = 0 (because they measure the origin o O'), so that 0 = Ax0 + C'x ; 0 = C'x0 + Ax; or 0 = (A + C'w/c)x0 ; 0 = (C' + A*w/c)x0, which should hold for any x0. Take the second one: C' + Aw/c = 0 if C'/A = -w/c (They use a less intuitive case, where O' is stationary and O moves toward negative x). Now, if A^2 - C'^2 = 1, we have A^2(1 - (w/c)^2) = 1, or A = 1/Sqrt{1 - (w/c)^2} [Eq. (35)]. In my convention, C' = -Aw/c. This corresponds to the \"active\" boost picture described in the Wikipedia article, in case you do some cross checking.\n\nQ5) RobusEtCeleritas explains this in his answer. The part about \"c going to infinity\" is not a good way of putting it because you need to take that subtle limit where w^2/c^2 is basically zero, but w/c isn't. The correct statement is that c is much larger than w, and the Galilean transformations appear to first order in w/c.\n\nI hope this helps."
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9iy50c | sir michael atiyah's solution to the riemann hypothesis and what it means for mathematics if confirmed to be correct. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9iy50c/eli5_sir_michael_atiyahs_solution_to_the_riemann/ | {
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"The early consensus seems to be that the alleged proof is deeply flawed, where “deeply flawed” is a euphemism for utter nonsense. The author is a renowned mathematician, but he's also 91 years old and he's been writing some very questionable stuff recently. Maybe someone will find something interesting in it, but it's likely that the alleged proof is not coherent enough to explain.",
"As has been said, the proof is most likely nonsense. \n\nBut, I’ll take a stab at your second question, which is what does it mean if it’s correct. \n\nHonestly, at this point, not that much. A lot of math has been developed on the assumption that the Reimann is correct (and on the assumption that it is not correct), so when it is proven/disproven, a good chunk of papers will become validated, and a different chunk will be invalidated. The key will be *how* the Reimann hypothesis is actually proved- whoever does it will likely have to invent some new cutting edge ideas, or relate it to something in a genius way. (The current proposed proof doesn’t do that, afaik, which is partly why there’s little hope for it). When a true proof does appear, the methods used in that proof will likely give rise to a lot of new and interesting math, which I can’t hope to guess at. "
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7329rw | why does the feeling of zero-g (without the physical resistance of water; like floating in the air) seem like a familiar feeling, despite never having experienced it? | To elaborate: doesn't the feeling of floating around, pushing off from a wall that's upside down or something with your feet and just floating towards something else, maybe grabbing onto something to stop your momentum, seem so familiar to you in a weird way? Isn't it just so easy to imagine that you can almost swear you've felt it before?
Not like swimming, where you can feel the pressure against you. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7329rw/eli5why_does_the_feeling_of_zerog_without_the/ | {
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"40 weeks in a womb? ",
"I have a question: Having not experienced it, how do you know it feels familiar? You're just assuming the sensation you imagine is accurate at that point, are you not? In which case it's 'familiar' in that you have no basis for comparison.",
"As a Lucid Dreamer I can say I experience this very exactly feeling regularly. Do you LD? If so, maybe that is the case. Or maybe it is just a good feeling for a thing you really admire.",
"Maybe you're confusing familiar feelings with intuitive/adaptive movement? If you're swimming and get caught in a strong turbulent current, your movements will almost intuitively work to counteract the turbulence and restore balance even if you've never been in that situation before.\n\nI think this is a testament to how adaptive your mind is rather than familiarity with the situation. "
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1b44hz | Could Earth capture new asteroids into its orbit? If so what would happen? | The moon currently orbits the Earth and Mars is surrounded by Deimos and Phobos. Is it possible for any near flying asteroid to be captured as well?
Is the earths gravitational pull strong enough to hold them?
I know size plays a role as smaller asteroids would be pulled through the atmosphere and destroyed, larger simply bypassing and shooting off into space. Is there a magical mass/size that would be just far away to survive and enter orbit?
What would happen if there was another satellite in orbit around earth? If it collided with the moon?
Thanks in advance!
| askscience | http://www.reddit.com/r/askscience/comments/1b44hz/could_earth_capture_new_asteroids_into_its_orbit/ | {
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" > Is the earths gravitational pull strong enough to hold them?\n\nSeeing as Earth is bigger than Mars, and our Moon is much larger than either of Mars' ones, yes!\n\n > Is there a magical mass/size that would be just far away to survive and enter orbit?\n\nIt depends more in what direction they come in from - you'd need to get the angle and speed just right to capture them in orbit. A smaller asteroid would be easier to capture than a large one, though, as you say.\n\n > What would happen if there was another satellite in orbit around earth? If it collided with the moon?\n\nIf it was the size of Deimos and Phobos, not much would happen - and the moon already has plenty of craters from asteroid impacts. For comparison, Deimos is 6.2km across, Phobos 11.1km, and the Moon is a much larger 1737.1km!\n\nThe largest asteroid (well, dwarf planet) inside of Jupiter's orbit [1 Ceres](_URL_0_) at a radius of 487.3km. It's still only about 1/80th the mass of the Moon, and so I can't see it having a huge effect on Earth (the Moon's main visible effect is the tide). It would be an impressive impact if it hit the Moon, but it would probably survive the impact and continue to orbit us merrily (although its orbit would be changed somewhat).",
"I highly recommend playing with [this gravity simulator](_URL_0_).\n\nIf you assume just two bodies (the earth and the incoming asteroid), then capturing is not possible. The incoming body may come close to earth, but it will be moving too fast to be captured. It may just sail by with a slight bend, or it may slingshot around.\n\nThe only way captures happen is when you add a third body. That could be another asteroid that is also making a close approach to earth at the same time, but in most likelihood, it would be our moon. As the asteroid approaches, the moon would absorb most of its kinetic energy, slowing it dramatically. If it happens just right, it may end the encounter with the moon with just the right trajectory and speed to enter a new tight elliptical orbit around the earth.\n\nOf course, with the moon being so much larger, and obviously intersecting our new asteroid-moon's orbit, the new orbit would only be stable for a short time (possible a few thousand years). Eventually it would either crash into the moon, be disrupted by the moon enough to crash into earth, or be flung far away again.\n\nOf course, if the third body was another asteroid, then a stable orbit could be made. Basically, two asteroids would interact far away from the earth-moon system, and one of the asteroids would be left with a trajectory that is almost motionless to earth. It would be just enough to keep it from falling back to earth, and the new asteroid-moon would orbit the gravitational center of the earth and the other moon. Of course, if the apogee was ever close enough to the first moon, then things would eventually be disrupted, so the entire orbit would need to be much further out than the first moon's orbit.\n\ntl;dr: It's nearly impossible, especially in a mature star system as our own.",
"[We have quasi-satellites](_URL_0_), but they will not be around forever."
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5qaavv | Could a tidally locked satellite such as our Moon experience seasons like we do on Earth? | Is it possible for a satellite that is tidally locked with its host planet to experience anything like the seasons we experience on Earth?
If so, what would be the prerequisites? | askscience | https://www.reddit.com/r/askscience/comments/5qaavv/could_a_tidally_locked_satellite_such_as_our_moon/ | {
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"There is no reason there couldn't be seasons, because the seasons have nothing to do with the rotation rate of the moon.\n\nOn Earth, the seasons are a result of the tilt of the Earth's axis relative to its orbit around the Sun. A tidally locked moon will generally align its spin axis with that of its planet. If the planetary spin axis was similar to Earth's, the moon would experience seasons similar to those on Earth. Even if there isn't enough time to align the spin and orbital axis, the moon's orbital axis would still produce seasons if it was similar to Earth's relative to the Sun."
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1040ix | How were the United States' capitals picked? Did they naturally arise from large cities, or was there some sort of deliberation? If so, what is taken into consideration? | I originally wanted to ask this question about nations and their capitals in general, but I thought it might be too broad of a question. If anyone wants to chime in about their area of expertise and how the capital is chosen I'd love to hear that as well.
**EDIT** Just want to say I'm enjoying everyone's responses about their states. Thanks so much. Now we just need some international people chiming in! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1040ix/how_were_the_united_states_capitals_picked_did/ | {
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"Many capitols were changed at one point because there was a push to put them toward the geographic center of the states. I'm too lazy to look up citation on that right now. ",
"Here in Alaska, the capital moved from Sitka, the capital of Russian America to Juneau in 1906 because at the time, Juneau was the economic heart of the Territory of Alaska.\nCapital moves have been repeatedly proposed throughout the 20th century but repeatedly shot down due to the informal desire of the framers of the Alaska constitution. In the 1950s, the thought was that Southeast Alaska should benefit from the capital and timber harvests, while Southcentral Alaska would benefit from fishing and the state's commercial hub. Interior and northern Alaska would rely upon mining and fur harvesting. Oil did not become a factor until after the constitution was drafted.",
"The story I heard about moving Texas' capital to Austin (from Houston) is mostly pettiness on behalf of the second president of the Republic of Texas who had a personal dislike for Sam Houston, the first capital's namesake and the Republic's first president.\n\nHowever, there's also the whole \"more centrally located than Houston\" bit, which is more likely to be true.",
"The capital of Florida (Tallahassee), was founded as the capital as a compromise between Jacksonville/st Augustine and Pensacola because at the time, most of the rest of Florida was wild (except for Tampa and Miami?)",
"Several of the changes had to do with transportation...moves from steamboat/riverways to train routes. Although, some were moved so that they represented a geographic center of the state...much like with Iowa, for example. The original capital was Iowa City, but they moved it shortly after to Des Moines due to its location within the state. ",
"After Kentucky became a state, it was decided that the capital would go to whichever town offered the biggest contribution towards a statehouse. Frankfort won. Most of the town was controlled by a single guy. It was an insignificant place. It was a terrible location and the town has always been small and overshadowed by Lexington and Louisville.",
"If I recall correctly, Sacramento was chosen as the capitol largely because there was a desire to move from the Spanish colonial capitol at Monterrey, but the facilities didn't really exist in San José or a new site proposed in present-day Benicia. So the first governor of California, [John Bigler](_URL_0_) proposed to move it to his home town, Sacramento. It did and eventually stuck, becoming the permanent capitol.",
"South Carolina's was moved to the middle of the state to take political power from Charleston and disperse it more evenly throughout the state.",
"I don't know all the details, but when Kansas was getting ready to become a state there was a lot of dispute over whether Kansas should be a free state or a slave state. As a result there were multiple state constitutions submitted (some with Kansas as a free state, others as a slave state). [One of the slave state constitutions](_URL_0_) had Lecompton as the state capitol and [most of the first floor of the capitol building had been built in Lecompton when they later decided that Topeka would be the capitol. ](_URL_0_)",
"Illinois had multiple temporary capitals before a permanent capitol building was built in Springfield, Sangamon County. Sangamon lobbied for it in the Illinois state legislature, and the effort to get the capitol for Springfield included Abraham Lincoln who was then a member of the Illinois House of Representatives for Sangamon County.",
"Olympia was constituted in its modern incarnation when the federal government placed the customs house for Puget Sound there, meaning all ships coming in from elsewhere had to check in there before continuing to their final destination. The customs house was moved a few years later to Port Townsend (which is at the head of Puget Sound), but the people stayed, and when Washington Territory was created, Isaac Stevens, the first territorial governor, chose Olympia to serve as the capital. It continued to serve in this capacity when Washington was carved off and made into a new state.",
"Usually countries have different reasons for picking their capitals and it's the same for states. The main reasons being either Trade and Financial Hubs, Defensible areas and due to the war ongoing in America State legislatures maybe couldn't be in the biggest city in the state as it was occupied.\n\nGeographical centres seems to also have been important in recent years.\n\nIn Europe though Capitals don't seem to shift as much, and it's mainly based on trade, Paris, London and Rome have been the trading hub of the world at one time or another.",
"Time to shamelessly high-jack this for a brief history of New Zealand (YAY first non-US post in this thread!) Because you should have asked the broader question so more of us could join in!\n\nPresently, the fine nation of New Zealand has [Wellington](_URL_4_) for a Capital City. The town was originally built as a port that could resupply sailing ships taking advantage of the [\"Roaring 40s\" trade winds that blow through the area](_URL_2_). \n\nOriginally though, New Zealand positioned its capital at a place called Kororareka (now called \"Russell\"). That particular town was well established as a hub of trade, but had certain problems as a capital in 1840: [it mainly serviced sailors and whalers on leave, and thus earned a well deserved reputation as lawless and full of prostitution. Literally it's nickname was the \"Hell Hole of the Pacific\". American sailors, apparently, really know how to party.\n\nBecause folks thought maybe having a capital famous for showing you a *really* good time might be... not the look a new country might aim for, the Capital was moved to [Auckland.](_URL_0_) Auckland was considered much better than Russell, but certain problems arose when the government realised the South Island of New Zealand might decide to be their own colony, thank you very much. The capital was moved to Wellington (much, MUCH closer to the South Island) in 1845 and there it has stayed ever since.\n\nJust completely because I love New Zealand in all its quirky glory, I give you [our parliament building](_URL_3_). If you're looking at that picture and thinking \"hey - the cool neoclassical building looks kinda... lopsided. And wtf is that tiered building?\" congratulations - that is the correct response. The cool neoclassical building was supposed to be nice and symmetrical, but we ran out of money. We had enough space for \"then\" (1907, I think), so we just left it like that... and when we DID run out of space during the 1960s, our prime minister decided we shouldn't just finish the building - instead we needed something else. Supposedly he drunkenly decided he needed a building that looked like the logo of [this box of matches](_URL_1_) The building IS called the beehive, although the story is *probably* untrue.\n\n",
"The original capital of Idaho was Lewiston, but the papers declaring it the capital were physically stolen and taken to Boise which then claimed the title.",
"The Capitol of Georgia used to be millegeville after it was moved from savanna because it was closer to the geographic center of the state. Then changed to Atlanta because it was a bigger city and the industrial heart of the south",
"Australia is an interesting case. Before Australia became independent Sydney, Melbourne, Brisbane, Adelaide and Perth were each the capital of their own independent colony. Both Melbourne and Sydney wanted to be the capital city (they were (and are) the two largest cities at time). Instead the British Parliament (or Queen Victoria) decreed that the capital should be a new city built between Melbourne and Sydney, but within 400km (or so) of Sydney. So a site was chosen and a city called Canberra will be built there.\n\nProblem is it took a while to be built. Australia became independent in 1901. The parliament house in Canberra was only built in 1927 (and it was literally in a [sheep paddock](_URL_0_). The only other things in Canberra were a few hotels for the politicians, and most of them stayed in a near by town (Queanbeyan).\n\nCanberra was really only a place for public servants and politicians for ages until the university (ANU) was built and then it grew somewhat. Its now a decent enough size city (360,000) people.\n\ntl;dr The Australian Capital was a sheep paddock for ages ",
"Some history of why Bonn (a tiny city at the Rhine) became the capital of West Germany after WWII.\n\nObviously it wasn't possible to make Berlin the capital since it was basically an island sourrounded by the East Germany. But they already put an article into the new constitution that Berlin would become the new capital once Germany became reunited.\n\nFour cities gave their bid to become the new capital: Frankfurt (today's main financial hub), Stuttgart (industrial center of South West Germany, Mercedes Benz), Kassel and Bonn. \n\nKassel was too close to the East German border. Stuttgart was bankrupt I believe. So only Frankfurt and Bonn were left. Frankfurt was the favourite for the Social Democrats and most Germans. Now, what you have to know is that Konrad Adenauer, later the first chancellor of Germany and most prominent figure of the Christian Democratic Union, was from a town close to Bonn and heavily favored it. Until the last minute Frankfurt was the favourite to win the decision but Adenauer used a never released press release that the Social Democrats were overjoyed to get a victory over the CDU. With this he was able to convince the CDU people from around Frankfurt to vote for Bonn.\n\nFrankfurt had already planned everything and had built an assembly room for the parliament. But in the end, it probably was a sensible solution. Frankfurt had been heavily destroyed during the war while Bonn was almost intact. So it probably saved a lot of money.",
"In Texas, there were arguments for years between Sam Houston and his supporters who wanted the capital in Houston and others who thought that Austin should be the capital. There was actually a small 'war' about it.\n\n_URL_0_",
"Quite frequently, it was felt that the Capital should be in a geographically and demographically central location, but not necessarily an economically central location, as it was felt that the 'corrupting influence' of urban metropolises should be avoided by central government. Often the capital was located in an area that wasn't quite developed yet, in order to help promote develop. Even DC, located on the fall-line as it is, was west of the mean center of the country's population when it was built. These influenced the location of places like DC, Albany, Columbia, Harrisburg, Sacramento, Olympia, or so forth. A great many capitals are not (or at least weren't) the largest cities because of this. ",
"I'd love to hear the reasoning for Harrisburg in PA if anyone has any insight..."
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3goaxv | why are exo-skeletons not much more commonplace? | As someone who has worked in construction and carpentry, exo-skeletons would have been a *massive* help when having to lift heavy objects and such. These would heavily benefits such highly physical jobs- why can't they be made readily available? They would be just like any other equipment used in the job. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3goaxv/eli5_why_are_exoskeletons_not_much_more/ | {
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"They're expensive, bulky, and they are just coming out with some that are usable in the real world",
"Basically it has to do with mobile power source. If there were batteries capable of powering a light exo power suit they would be a lot more commonplace. \n\nThe [exo suit in the movie \"Aliens\"](_URL_0_) would be extremely useful, but if you have to attach a large internal combustion engine to get a feasible energy density power source you might as well make the thing twice as big and make it a forklift and save yourself the engineering headache..."
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22i1rs | For billions of years life on earth consisted of simple single cell organisms that reproduced by splitting into two, like the bacteria we see today. Why or how did sex begin? | How did evolution decide it was better for two organisms to mate, creating a single offspring, rather than a single organism to divide creating two offspring? Did two different types of bacteria kinda bump together and meld into one, making a more complex organism? If so, wouldn't the two original bacteria be eradicated? How did it occur that two organisms came together, created a single offspring, and still survived individually to procreate further if they fancied it? | askscience | http://www.reddit.com/r/askscience/comments/22i1rs/for_billions_of_years_life_on_earth_consisted_of/ | {
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"When you look at the basic algorithms that describe evolution, they clearly show that more variation equals more success for the species. Sex in and of itself was simply a beneficial mutation. \n\nAs for the how, the chemical processes that underlie meiosis are very similar to those of proteins that help repair DNA damage. In fact, primitive sex was likely just a method of one unicellular organism replicating the DNA of a similar organism in place of its own damaged DNA. ",
"So the real answer is that there are organisms that developed the ability to mate both sexually and to clone within the same organism, like a lot of protists and some fungi. (for more information, google \"chlamydomonas life cycle\")\n\nWhen you're that small, you can afford to just make a ton of clones and scatter all over the world and conjugation and random mutation will be enough. But when you're a large and it takes longer than 20 minutes to reach maturity and reproduce again, the populations that survived were ones that were more diverse."
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642rug | why do most females "throw like girls"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/642rug/eli5_why_do_most_females_throw_like_girls/ | {
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"It's just from lack of proper instruction. At least in the US, people (boys and girls) who don't play baseball or softball aren't taught proper throwing mechanics, and the \"elbow in front of the hand\" technique is just what your brain thinks needs to happen.\n\nTry to throw with your non-dominant hand and see if you \"throw like a girl\" I bet dollars to donuts you will.",
"\"Throwing like a girl\" is really not knowing how to throw properly, lack of practice, and a lack of muscle memory. Your left arm is evidence of that. The phrase most likely came about because boys have historically been more interested in playing sports while girls were often actively discouraged from playing, leading to the belief that an inexperienced arm is a \"girls arm,\" so to speak. There is no structural difference between a girl's and boy's arm that would make someone throw a ball differently.",
"People in this thread have mentioned that girls who \"throw like girls\" don't have athletic training, which is definitely true and almost certainly the primary factor.\n\nHowever, it would be unfair not to mention that women are physically weaker than men. Studies have suggested that nearly all women are weaker than nearly all men. [Graph.](_URL_0_) I mention this only because OP asked if there was a physical difference. There is, it's just not the biggest factor.",
"Blah blah triggered etc anyway this is actually interesting my sister and I were both pitchers in a softball league, it took her a lot longer to get the hang of it underhanded but once she did she was more accurate then me although my pitches were way faster. When we threw overhand no matter how many times they tried to beat It into her head she always \"threw like a girl\". All the guys got it immediately they threw like a hardball pitcher while all the girls did this weird throw using a shit ton of elbow and the arm would only extend at the last minute causing an extremely weak throw overhand. Personally I think it has to do with how the brain works. Only 1 girl got the hang of it at a decent rate out of the 10 that were on the team. After a few years that weird throw was eventually ironed out of their brains but they all did that weird elbow throw for ages. Science dictates that most girls tend to be better right hemisphere and men better left hemisphere so I would say that has something to do with it. Dudes tend to be really good at replicating actions and things while women seem better at coming up with original ideas and planning for most scenarios.\n\nAt the Olympic stage women are 10% weaker than men which is negligible. This gap become a lot wider in normal everyday life as women tend to be smaller then males. When you take all the feminism and bullshit out of it and look at the data it can be really revealing. "
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18ic20 | Do you get tanned through normal windows? | askscience | http://www.reddit.com/r/askscience/comments/18ic20/do_you_get_tanned_through_normal_windows/ | {
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"Nothing is completely transparent to everything in the EM spectrum. Even windows absorb small amounts of light - consider the \"greening\" effect of facing \"infinite\" mirrors. They assuredly block a decent amount of shorter wavelength UV light, and you can get commercial glass designed to be almost entirely opaque to the UV spectrum.\n\nWhile that won't prevent you from \"cooking skin\" via infrared, it will slow any attempt at tanning to a noticeable degree. "
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1ula6t | how congress is voting for their own pay raises. | Is it a bill? A law? Or do they just sit around and say "We should be making more money, let's have a vote"? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ula6t/eli5_how_congress_is_voting_for_their_own_pay/ | {
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"For the past twenty-five years or so, congressmen have gotten automatic cost-of-living adjustments to their pay, so actually passing a bill to give themselves a raise is rare. But yeah, it could be a standalone bill, or tacked on as part of a different bill, like a Treasury Appropriations bill."
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52htvc | why are animals sometimes rejected by their families ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/52htvc/eli5_why_are_animals_sometimes_rejected_by_their/ | {
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"Various reasons but essentially it's survival of the fittest. If a parent knows that their young is weak, or won't likely survive, they'll reject it and often times kill it. \n\n",
"A lot of reasons, big one is resources. Raising young is a big investment of time and energy to feed, clean, and protect them. So if it is clear that the youngster isn't going to make it due to permanent injury or disease, the parents may ignore it so their efforts could them be invested in young that have a much better chance of survival. Also in the case of disease, the parents may dispose of sick baby to prevent the others from falling ill.",
"Survival. Weakness in the wilderness among animals that eat each other surely means death. This law, unfortunately, is even ingrained upon apex predators. ",
"Resources, illness and deformity. I see people misquoting \"survival of the fittest\" which refers to the environmental adaptation and filling niches but they're still *close* to the right track."
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uhscu | Why are headphones more damaging to hearing than open speakers, even if I can hear speakers playing over my headphones? | askscience | http://www.reddit.com/r/askscience/comments/uhscu/why_are_headphones_more_damaging_to_hearing_than/ | {
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"They're not. It's just that it's a tad easier to lack caution and have the volume set too loud with headphones than open speakers. And those who do, do this often, and use their headphones often."
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3qtloj | if clouds get too heavy when it rains, how do they manage to hold large pieces of ice (hail) | So this happened where my family lives in Australia _URL_0_
My uncle owns a farm here where his crops have been destroyed by this freak of nature storm. So would like to know how this all happens. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qtloj/eli5_if_clouds_get_too_heavy_when_it_rains_how_do/ | {
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"Hail is carried upwards by very powerful updrafts that occur within a storm. They're not held up by buoyancy, they're thrown upward by sharp gusts of wind."
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6ifqoc | Why does the American southwest get so hot? | Phoenix, AZ is going to be so hot that flights are being canceled because of the heat (120F / 49C). Why does it get so hot there when other states in the south (for instance, Texas) are closer to the equator? | askscience | https://www.reddit.com/r/askscience/comments/6ifqoc/why_does_the_american_southwest_get_so_hot/ | {
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"\n\nWhy is SW Arizona, SE Cal, so hot?\n\n 1. The air is very dry. The warm waters of the Gulf add moisture to the air throughout most of the South. The realtively cold waters off the S. California coast don't have much summertime influence more than a few miles inland. Dry air heats up (and cools) more readily than humid air. At this moment, it is 119°F, only 6% relative humidity.\n\n 2. High pressure systems often camp out over the Great Basin region in the early summer before shifting east later. High pressure usually indicates subsidence, or descending air. Descending air warms and dries, leading to clear sunny skies. Cloudless skies = higher insolation = hot.\n\nBTW, only one airline cancelled flights of some of its smaller commuter planes. Nothing like back in 1990 when they shutdown the airport as the temperature reached 122°F (50°C). (Flight computers only handled temps up to 120°F.)",
"The equator receives the most sunlight of any area on Earth, so you'd expect it to be the hottest, but it turns out that high temperature records across the globe are consistently set closer to +/- 30 degrees latitude, the so-called 'horse latitudes'. It turns out that much of the excess heat at the equator is transported to the horse latitudes.\n\nAt the equator, quite a bit of the solar heating goes into evaporation of water rather than raising the temperature, so the equator itself is a bit cooler than if the Earth were bone dry. All this evaporation creates warm, moist air over the equatorial oceans, and this air begins rising. As it rises, it reaches lower and lower pressures, where it expands and cools. All the excess water vapor that was in the air starts condensing into clouds now that its colder.\n\nThere's an interesting effect that happens here: the transition of water vapor (a gas) to cloud droplets (a liquid) releases heat back into the air - this is actually the exact opposite effect of water needing heat to initially evaporate from the ocean. This heat released from condensing clouds goes back into warming that rising air. The result is that rising moist air only loses about 6 C for each kilometer it rises, while dry air has no heat from moisture to regain, so it loses more like 10 C per kilometer.\n\nMeanwhile, even though the moisture has now been deposited into clouds, the air itself (now very dry) continues rising. That same dry air then begins to head in the direction of the poles, but is halted in its journey around +/- 30 degrees latitude as the Coriolis force prevents it from moving more poleward. It then proceeds to descend to the surface as very dry air around those same latitudes, eventually looping back closer to the surface to the equator. This cycle produces the Hadley cell, as seen in [this diagram](_URL_0_). \n\nNow all this dry descending air around the horse latitudes leads to vast areas of deserts at those locations. In the Northern Hemisphere, there's the American Southwest, the Sahara, and the Middle East. In the Southern Hemisphere, there's the Atacama Desert in Chile, the Kalahari Desert in Namibia, and the Australian Outback. Obviously not everywhere at these latitudes is desert, since local currents can affect the area's climate (e.g. the American Southeast has the Gulf of Mexico to help maintain moisture and cooler temps), but deserts are the general trend.\n\nSo why is it hotter there? Well, let's track a bubble of air:\n\n- We start at 30 C (86F) over the equator and lift our bubble of moist air to 3 km, losing moisture as clouds along the way. Since rising moist air loses about 6 C per km, the now-dry air is at 30C - 6 C/km * 3 km = 12 C (54F). \n\n- The dry air then continues upwards up to about 10 km. Since dry air loses about 10 C per km, the additional 7 km of height decrease the temperature down to 12 C - 10 C/km * 7 km = -58 C (-72F). \n\n- The air now travels poleward, when it then descends the 10 km down to the surface as dry air over the horse latitudes. Since it's dry, it now gains 10 C per km, so its temperature will now be -58 C + 10 C/km * 10 km = 42 C (108F), which is hotter than it originally was at the equator.\n\nIn other words, when the air was rising over the equator, it didn't cool as much since the first 3 km formed clouds, which pumped some heat back into the air. That heat becomes very noticeable when it returned to the ground at the horse latitudes, producing surface temperatures that are hotter than the equator."
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6sh8f6 | how is microfiber cloth so much better than regular cloths? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6sh8f6/eli5_how_is_microfiber_cloth_so_much_better_than/ | {
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"Teri cloth (Normal towels) have many little loops of fiber that soak up water.\n\nMicro fiber has little hairs- with little hairs on them. It's much more surface area for moisture to be sucked in to.\n\nMicro fiber has the added benefit of being less linty than other cloths, which make it more ideal for surfaces prone to scratching, like glass and plastic screens."
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5ppp9q | Why is concussion so dangerous in young people, given the brains plasticity? | Concussion is currently an issue in several sports (particularly rugby, football (soccer), American football), but given the age of most high-end sport stars, why is this such a problem? Aside from short-term memory loss, shouldn't the brain be able to recover various functions? Or have I completely misunderstood brain plasticity? | askscience | https://www.reddit.com/r/askscience/comments/5ppp9q/why_is_concussion_so_dangerous_in_young_people/ | {
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"I think you might misunderstand what plasticity is. You seem to have the general idea--that plasticity has to do with the ability of the brain to change. However, I think you're overestimating plasticity and perhaps missing a few pieces. \n\nPlasticity, generally speaking, is the ability of brain connections (synapses) to form and and unform (prune). It is true that a child's brain is generally more plastic than an adult's, but there is still a good amount of plasticity in the adult brain! \n\nNeuroscientists don't completely understand what is happening during a concussion, but it's generally accepted that it's never good to have one. A reason why it might be particularly bad in children is that children are undergoing a ton of learning and going through critical developmental periods. There are certain time periods when you have to learn something or you likely never will or it will be much more difficult (think language as a small child). \n \nHope this helps!",
"You have misunderstood plasticity. The brain is plastic in that it can continue to grow dendritic connections between neurons. It's not plastic like it can recover from trauma. In fact it really can't recover at all, you can just try and learn ways around traumatic brain injuries. When a neuron dies, it's not coming back. Granted I don't think that concussions result in neuronal death. There is a recent good review of concussive trauma in childhood, lemme see if I can find it. ",
"I think this is a really interesting question, other commentators have covered plasticity well, but I want to add a couple of other points.\n\nFirst of all yes young people do have more brain plasticity but there is a sort of catch-22 in play. In many respects young people have greater chance of recovery from brain injury because their brain development is continuing and this development might help recovery (or as someone else pointed out, more accurately help the brain 'work-around') an injury. HOWEVER equally a developing brain is more vulnerable because it is developing.\n\nI like the analogy of a house being built. Some fool messes with the construction and part of the roof collapses. Depending on where the damage is and what stage the construction is, it may be relatively simple to continue building and essentially repair the damage as new. However its also possible the damage totally halts construction, and results in a long term permanent hole in the roof that the finished product still has. \n\nI hope that vaguely makes some kind of sense - also to add there seems to be more evidence coming out that concussion is damage to the brain on a cellular level. If you consider the analogy again as being damage to the materials of a construction, this can be extremely serious to the overall structure of the house. It used to be though that concussion was just a temporary injury because of the lack of gross brain damage, however that is being rethought. "
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bcmgl9 | Are there any organisms that are known to use heat as a source of energy? | Organisms generate energy for themselves in a variety of ways, from breaking down chemicals, absorbing sunlight, to even subsisting off of radiation that would kill most other forms of life in Chernobyl. [_URL_0_](_URL_1_)
In addition, many organisms thrive in high-temperature environments, such as deep-sea thermal vents or even deep underground. But I was wondering: are there any known life-forms that can convert heat into energy like a plant converts sunlight into energy? | askscience | https://www.reddit.com/r/askscience/comments/bcmgl9/are_there_any_organisms_that_are_known_to_use/ | {
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"This is not a biological question - it is a physical one, a thermodynamic one.\n\nTemperature is not a source of energy. A hot thing in a hot environment does not have any energy available to it. In order to obtain energy, you need a hot place and a cold place, and the movement of heat across that difference in temperature can be a source of energy. It can drive a heat engine.\n\nIn order to survive in hot environments, a life form has to be simple, which means it has to be small, which means it is not going to have any kind of 'heat gradient' - a hot place in one part of it and a cold place in another - from which to extract energy."
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mzwu9 | Is the total amount of information limited? | As I understood, the total amount of energy in our universe is limited (conservation of energy law). What about information? Is the information limited? I mean information in general, not how many TB we store on our hard drives.
EDIT: Let's put it this way: the information, that was not created by humans (like the time you wake up or how many surgeries you had), but the information, that was contained in the universe before human beings and does not depend on them, people just discovered it (like the speed of light or conservation of energy law). I hope it is an appropriate distinction. | askscience | http://www.reddit.com/r/askscience/comments/mzwu9/is_the_total_amount_of_information_limited/ | {
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"That's a really cool question. The entropy of a certain area is limited by the entropy of a black-hole with that size. This is called the Bekenstein bound: _URL_0_ ",
"Yes, although for all practical purposes we dont have to worry about ever reaching that limit. Information is simply the arrangement of matter. When a company seeks to create a new piece of hardware that can store information they increase the number of transistors on that piece of hardware. Each transistor has 2 possible states, and adding more increases the number of possible combinations. These transistors can be made smaller and smaller until you are dealing with how matter is organized at a quantum level. Since there are a finite number of quantum states and a finite amount of matter there must be a finite amount of information that can be stored.\nEntropy (the degree to which matter is unorganized) plays in here. If we discovered that there are an infinite number of quantum states it still would not mean that we could store infinite information, because entropy always tends to increase over time, and putting energy from one system into another to access more quantum states results in a net gain of entropy.\nAlso, even if the total energy of the universe was infinite, it is possible for the amount of information we could store to be zero, if the universe were as randomized as possible (ie all matter would be the same temperature and have no potential energy). The amount of free energy in a system is a better measure of how much information you could store in it. If you had infinite transistors but they could all only exist in the same state, you could only store one bit of information.\n",
"We can view the universe as essentially a \"boson gas\" inhabited entirely by photons at a constant temperature of around 2.73 K. Integrating heat capacity over temperature with the approximate volume of the universe gives a total entropy of around 10^88, which is enormous.",
"That's a really cool question. The entropy of a certain area is limited by the entropy of a black-hole with that size. This is called the Bekenstein bound: _URL_0_ ",
"Yes, although for all practical purposes we dont have to worry about ever reaching that limit. Information is simply the arrangement of matter. When a company seeks to create a new piece of hardware that can store information they increase the number of transistors on that piece of hardware. Each transistor has 2 possible states, and adding more increases the number of possible combinations. These transistors can be made smaller and smaller until you are dealing with how matter is organized at a quantum level. Since there are a finite number of quantum states and a finite amount of matter there must be a finite amount of information that can be stored.\nEntropy (the degree to which matter is unorganized) plays in here. If we discovered that there are an infinite number of quantum states it still would not mean that we could store infinite information, because entropy always tends to increase over time, and putting energy from one system into another to access more quantum states results in a net gain of entropy.\nAlso, even if the total energy of the universe was infinite, it is possible for the amount of information we could store to be zero, if the universe were as randomized as possible (ie all matter would be the same temperature and have no potential energy). The amount of free energy in a system is a better measure of how much information you could store in it. If you had infinite transistors but they could all only exist in the same state, you could only store one bit of information.\n",
"We can view the universe as essentially a \"boson gas\" inhabited entirely by photons at a constant temperature of around 2.73 K. Integrating heat capacity over temperature with the approximate volume of the universe gives a total entropy of around 10^88, which is enormous."
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5hzqwd | I've seen a lot of people say that the US contributed little in WW2 compared to the Soviets. How true is this? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5hzqwd/ive_seen_a_lot_of_people_say_that_the_us/ | {
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"I will say in general from the get go discussion about how \"The Russians won WW2\" are generally and unfortunately Eurocentric. While certainly much of the developed world was more immediately impacted by the war in Europe, and thus much of Reddit's user base, it should always be questioned.\n\nIt ignores the millions of Americans, Kiwis, Aussies, Brits, Canadians, French, Dutch, Tagalog, Chinese, Vietnamese, Polynesians, Koreans, Indian and others involved in the war against Japan. The killing started well before stormclouds darkened in Europe and continued after Hitler was dead and Berlin rubble. And was waged across half the surface of the earth and resulted in a similar amount of human lives destroyed, without a systemic industrialized genocide mind you. \n\nTo talk about all of WW2 when you really only mean the war against Nazi Germany(and maybe Italy and the other Axis Powers), it diminishes the entire other half of the global tragedy of the war. ",
"Human losses is a huge part of the reason people say that the Soviet Union (of which Russians were only one part, though it was a large part) made the largest contribution to winning WWII. That is because, out of the roughly 60 million people who died during WWII, 27-28 million of them were Soviet citizens. 8-8.5 million of those were Soviet soldiers. The rest were civilians. One of the key arguments behind the Soviets-won-the-war argument is that the war would have ended before Western allies such as Canada, the Kiwis and the USA had time to enter it, if the USSR had not held out through 1941-1942. \nYes, we should keep in mind the role of fighting in Asia when considering this. And no, we do not have to agree 100% with the statement that the Soviet Union contributed 'more' than the US. But in terms of loss of life, it isn't even in the same order of magnitude. So the contribution of the United States and other western militaries was clearly focused in a different way. I think it is fair to generalize by saying that the USA contributed to the war in a ver significant economic way. The Lend-Lease program was very important, including to the Soviets. The British made key discoveries in the field of intelligence. They cracked the enigma machine, and that played a role in the later stages of the war particularly. All these things matter. And there is no good, easy metric for weighing an intelligence discovery against human life, or the investment of $1 million dollars worth of tanks against human life. So I think it's ultimately an ahistorical question to ask who contributed more/the most, if we are not going to specify parameters.\nBut anyone who wants to downplay the role of the Soviet Union in WWII should stop and think about the 27-28 million lives lost by that country during the fight against Nazi Germany. That is nearly half the total lives lost in WWII. 20 million of those were civilians. These people bore the brunt of German brutality for years (as did Poland). Deaths are as high as they are because of the incredibly low value the German occupation forces and front-line military placed on Soviet lives. \nSo let's not downplay the role of other allies, but everyone ought to take a moment to appreciate how much ordinary Soviet citizens suffered and sacrificed. Canadians, Kiwis and Americans experienced nothing close to the loss of life and societal disruption that Soviet society did. ",
"From /u/marisacoulter\n\n > So let's not downplay the role of other allies\n\nI agree. While it's fine to speculate on the details of who-did-what, I find that answers to this question are almost always politically charged: either to diminish the efforts of the Soviets or the western allies. The very best way to approach it is as a team effort in which all parties contributed significantly.\n\nOnly a fool would maintain that the Soviet Union did not do the majority of the killing and dying, especially prior to 1944. North Africa and the Mediterranean Theater as a whole has been rightly called a sideshow, in that the forces committed were vastly smaller than on the eastern front and did not decisively impact the outcome of the war. However, it is easy to underestimate the degree to which the pressure exerted by the western allies aided the Soviet war effort, especially in the last critical year of the war. \n\nThe North African campaign accounted for more than 400,000 Axis casualties and caused irreplaceable materiel losses, especially to the Italian navy. The subsequent invasion of Sicily and Italy knocked Italy out of the war and added another 400,000 to 600,000 German casualties, in addition to the 1,000,000 Germans who surrendered there at the end of the war - men who otherwise would have been available to fight in other theaters. \n\nBy late spring-summer 1944, when Operation Bagration smashed the German Army Group Center and crippled the German ability to meaningfully resist, only about 60% of the German Army remained in the east. The remainder was split between defending Italy, France, and Norway and fighting partisans in Yugoslavia. Due to the allied bomber offensive, the best part of the *Luftwaffe* had been withdrawn to Germany and France, and would be largely used up in defending against this threat by the end of the year. The Normandy Campaign, while often overstated by westerners, was an unmitigated disaster for German arms, made all the worse because it occurred near simultaneously with Operation Bagration. The bulk of Army Group B - 38 divisions in all - was destroyed or crippled. More than a third of Germany's elite mechanized divisions was wiped out, permanently crippling the German capability for offensive warfare (the Ardennes Offensive was only possible by stripping units from all other sectors, and even then German forces were surprisingly weak and basically foredoomed to failure).\n\nIn summation, the sacrifices of the Soviet Union cannot be overstated. They were *the* decisive factor in the defeat of Nazi Germany; without their continued resistance, it's difficult to see just how the war could have been won. However, I find it equally difficult to imagine how the war would have gone without the western allies exerting such considerable pressure on the German flank. At the very least, the Soviets would have had to fight *millions* more men and thousands more tanks and airplanes on their way to Berlin.",
"Others have provided some good answers, but [I'd also direct you to this old response I wrote on this topic.](_URL_0_)"
]
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3lf6wc | How did scientists find out the composition of DNA? | I was reading [this](_URL_0_) journal which discusses the possibility that a bacterium could use arsenic instead of phosphorus in its DNA which turned out to be false. This led me to wonder how scientists first isolated different components of DNA and what technique they used. I was also wondering what modern techniques could be used to find out composition of DNA. Thanks! | askscience | https://www.reddit.com/r/askscience/comments/3lf6wc/how_did_scientists_find_out_the_composition_of_dna/ | {
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"You mean elemental composition? Well, [Miescher](_URL_3_) first isolated DNA, extracting it from infected medical bandages. It was already known in Miescher's time that it contained phosphorus, I believe from ashing experiments. At the time it was routine to decompose compounds using acid, basic, and high temperatures and characterize the breakdown products. \n\n[You can read about the history in Box 3, here](_URL_0_).\n\nNowadays, we'd probably use [X-ray fluorescence](_URL_5_) to quantify the elements in DNA, but I'm not an expert in that technique. \n\nAs for chemical composition, [Kossel](_URL_2_) determined that it contained four nitrogenous bases, and [Levene](_URL_4_) found they were linked in a phosphate-sugar chain. [Chargaff](_URL_1_) found that any DNA will have equal ratios of Adenine to Thymine, and Guanine to Cysosine, which was key to later figuring out the structure of DNA. \n\nThe paper you link to was unfortunately what appears to be a bout of wishful thinking gone awry, which is too bad, because it would be interesting if it were true!"
]
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"https://en.wikipedia.org/wiki/Erwin_Chargaff",
"https://en.wikipedia.org/wiki/Albrecht_Kossel",
"https://en.wikipedia.org/wiki/Friedrich_Miescher",
"https://en.wikipedia.org/wiki/Phoebus_Levene",
"https://en.wikipedia.o... | |
6i4ka0 | why were large denominations of us currency discontinued when it seems more reasonable to use them in present day? | With inflation and such, it seems more reasonable today to use a $1000 bill than it would have 100 years ago. Why were large bills in circulation back then and not today? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6i4ka0/eli5_why_were_large_denominations_of_us_currency/ | {
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"100 years ago we didn't have nearly the same ability to do electronic transactions. Now more and more large transactions are being done electronically. There is less and less need to have any paper money, especially bills larger than what would be normal small expenses. In fact, there is a growing movement to ban bills like the 100 dollar bill as it has little practical use besides being used for tax evasion and drug trafficking. \n\nEdit: Just a thought experiment for you:\n\n* How does your job pay you? Cash, check, or direct deposit?\n\n* Do you ever have all of your money from a pay period in cash?\n\n* Did you purchase your car and/or house in cash? Do you make payments on either in cash?\n\n* When was the last time you bought something with cash that was over 200 dollars? (Combined or individually)\n\nFor me the answers are direct deposit, never, paid through check/auto-debit, and can't remember ever doing that. "
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372lsu | what is the difference between a muscle car and a sports car? | Everything from how do the bodies differ to how they are powerful/fast. Google answers I found were either too vague or had too much jargon.
Edit: thanks for all the replies everyone | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/372lsu/eli5_what_is_the_difference_between_a_muscle_car/ | {
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"Muscle car - car that can go really fast in a straight line, but can't handle. A lot of muscle cars are really heavy and have a big engine.\n\nSports car - car that can handle very well, tends to be light. These don't have as much power, but make up for it with less weight, so they can still accelerate pretty quickly, but can also handle. They're also a lot smaller.",
"IMO \n\nMuscle Car: usually a rear wheel drive V8 with straight line speed and lots of Horse Power\n\nSport Car: better and cornering and acceleration, a more total driving experience "
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4ttn7r | why are there still so many electronics devices like printers that give cryptic error codes instead of just a plain english explanation of what's wrong? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ttn7r/eli5_why_are_there_still_so_many_electronics/ | {
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"Two things, the first is complexity, devices with a tiny 16 character display really don't have much of an option to display a full error message and might not have the capability to store that text internally (it's an extremely simple processor), error codes are a simple way to give the user a very condensed description, where they can look it up.\n\nSecond, it's sometimes just the work and effort in displaying the error isn't worth the effort for the quantity of errors the developer wants. A good example of this is the way the C programming language works, there is one variable, errno which contains a single number, there is a large list of predefined errors, and a library can state that error simply by writing one number to one variable. This is extremely simple, ensures that almost anything can issue an error (don't have to worry about writing out to the error object, locks, permissions, etc), and an error handler can simply check this periodically and display the easy to read error code. Sometimes you get numbers because developers don't really track their codes, and just put numbers in, it's enough for them to track it down, and while not really helpful to you, it's likely the real description of the problem wouldn't be helpful to you too."
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kj1sv | Can somebody slightly "dumb-down" the four levels of protein structure for me? | I am reading my biology textbook and I'm on the chapter about proteins. This textbook supplies a lot of details about protein structure (primary, secondary, tertiary, and quaternary) that are relatively easy to comprehend but it doesn't really break anything down into a basic, summarizing statement.
Basically, I have knowledge about the specifics of protein structure levels but none of the details are fitting together in my brain to form a real picture of what it all means.
Thank you. | askscience | http://www.reddit.com/r/askscience/comments/kj1sv/can_somebody_slightly_dumbdown_the_four_levels_of/ | {
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"Primary: the sequence of amino acids that make up the protein.\nSecondary: alpha helices and beta pleated sheets\nTertiary: the overall 3-D shape of the protein\nQuaternary: multiple proteins stuck together",
"ELI5 version (Using Power Rangers):\n\nPrimary: The smaller parts that make up the zord (i.e. ball bearings, connecting rods, etc.)\n\nSecondary: The specific structures of the Zord (i.e. arm + leg = alpha helices, torso = beta sheet)\n\nTertiary: Zord\n\nQuaternary: Megazord\n\n\np.s. in case you didn't know the zords are their animal robots that they drive",
"Primary: the sequence of amino acids that make up the protein.\nSecondary: alpha helices and beta pleated sheets\nTertiary: the overall 3-D shape of the protein\nQuaternary: multiple proteins stuck together",
"ELI5 version (Using Power Rangers):\n\nPrimary: The smaller parts that make up the zord (i.e. ball bearings, connecting rods, etc.)\n\nSecondary: The specific structures of the Zord (i.e. arm + leg = alpha helices, torso = beta sheet)\n\nTertiary: Zord\n\nQuaternary: Megazord\n\n\np.s. in case you didn't know the zords are their animal robots that they drive"
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4ll8sk | What conditions need to be met for computer code to be considered artificial intelligence? | askscience | https://www.reddit.com/r/askscience/comments/4ll8sk/what_conditions_need_to_be_met_for_computer_code/ | {
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"This past semester i took a class in AI and what we studied basically is that AI is the capacity of a computer to perform operations that would normally require intelligence if they are performed by humans, for example decision making, perception and recognition of shapes, etc. So to code a program able to do something like that, your code need to incorporate certain AI \"tools\" like backtracking search algorithms and depth-first algorithms, etc, and your program should also be able to evolve on its own thanks to an automated learning process (aka machine learning) and you should use for that decision trees algorithms. All of this basic AI tools are used in the most evolved artificially intelligent computer programs (alpha go for instance) in some way or another.\nps: Tic-tac-toe in python is a good and fun way to start.",
"I haven't seen a formal definition of artificial intelligence. What I have seen is a definition of [intelligent agent](_URL_0_) as a machine that has sensors, effectors and an internal logic such that:\n\nf: P* - > A\n\nWhere P is the set of possible perceptions from the sensors (the star here denotes that this is an arbitrary-length list, as an extension of the concept of ordered pair) and A is the set of possible actions of its effectors. The F here is denoting that it's a function, so that two instances of the same agent that have the exact same history of perceptions will take the exact same actions. (Compare this to the definition of algorithm, that requires that the same result is yielded if ran several times with the same inputs).\n\nInformally, I'd say the defining feature of AI is that the programmer only codes the rules that the agent will use to chose its actions, but the actual decision of what actions to take is left to the algorithm.\n\nThink about goal-based agents: You tell the agent what you want to do, the agent can predict how the results of its actions will effect the environment, and based on that and on the perceptions of its sensors, it can deduct a sequence of actions that will take it to achieving the goal. Think of a GPS navigator: it knows what road it is in, what road it will be if it takes a turn, and you tell it where you want to go. Then the agent will output the sequence of car turns that will take you there. The programmer didn't (and couldn't) know these actions in advance.\n\n(Strictly speaking, saying that a GPS navigator is an intelligent agent is arguable because it's not actually controlling your car: no effectors. But it's ok, we can stretch a bit the definition.)"
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Intelligent_agent"
]
] | ||
3oqlp0 | why is it a "social faux pas" to talk about who you vote for? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3oqlp0/eli5_why_is_it_a_social_faux_pas_to_talk_about/ | {
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"text": [
"Some of it is that a private ballot is seen as a protection against being forced to vote for a particular candidate. You may have an oppressive boss, spouse, parent, whatever but they never have to know which lever you pulled inside that little curtain. \n\nSome of it is just that politics tends to make a lot of people passionate and if you know something can easily lead to a heated argument then maybe its best not to bring it up at all, particularly with someone you've just met. Or if you're in a group of people and not all of them feel as passionately as you do. ",
"I know that at work, I avoid talking about politics at all - there are too many possible ways to offend or to get into arguments. It's a shame, but people often become very heated and angry when discussing politics with someone who doesn't share their political leanings - it just isn't appropriate in certain circumstances. ",
"It really depends on the context, among friends talking about politics is fine, but its considered rude if you are at a party or among acquaintances/co-workers/people you never met/the girlfriends family, etc. etc, etc. because politics is often a very divisive issue and can bring up a lot of ill feelings especially if you mix in a few drinks. Therefore its best not to talk politics unless everyone in the room is expressly interested in talking about politics. My grandfather once told me not to talk about religion politics or hockey unless you are looking for a fight, obviously I'm Canadian but I think the point stands. "
]
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[],
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[]
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