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fcc4ru | why don’t we see only perfect black when our eyes are closed?🙈 | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fcc4ru/eli5_why_dont_we_see_only_perfect_black_when_our/ | {
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"The visual processing apparatus in your brain won’t ever get zero signal unless you’re dead. There’s always some “noise” in the machine, which your pattern-matching devices will fall over themselves to “interpret” into a meaningful picture. \n\nYou may note the visuals you do see inside your closed eyes are often rhythmic series of waves or ripples, which may be cycles of non-zero stimulation washing across the layers of neurones. \n\nAlso, your eyelids are not fully opaque, so there’s also light leakage inside the eyeball which, again, your pattern-matching drive will try to turn into something intelligible."
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o4jjy | why israel seems a lot more developed and rich than many other middle eastern countries | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/o4jjy/eli5_why_israel_seems_a_lot_more_developed_and/ | {
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"To begin with, Israel isn't much richer than most middle eastern countries, since (a lot of them) have oil. \nIsrael *is* more developed than most of those countries, and has a higher GDP(The amount the country produces in American $) per person.\n\nThe immediate cause of this is that the economies of the rich middle eastern countries is based on their natural resources (oil mostly), which Israel's economy is based on their human capital (an educated and technically competent workforce). \nGoing one step back, countries that, at their foundation, do have a lot of wealth in natural resources tend not to invest that in human capital, this is called the [Resource Curse](_URL_0_) and there are a lot of possible explanations for it, but no certain one, nor any one that fits every case (this happens a lot in Africa, as well). \nIsrael, on the other hand, who only recently discovered natural resources (large natural gas deposits off the northern part of the coast), could not grow it's economy with any resources other than human capital. \n\nThat is true for a lot of countries, however in Israel's history there were a series of both good decisions/policies on the part of it's government, and a flow of cash donations and resources from outside the country that enabled it to grow it's technology and defense sectors large enough to sustain a modern economy. \n\nThe first part, the good policies, include most glaringly the large investment the Israeli army makes into maintaining a technological edge over it's enemies - Israel's army is a conscription army (every non arab citizen has to server for 3 years in the army) and it enabled people with a natural aptitude (and the an acceptable socioeconomic background) for technology to serve in the Israeli military intelligence, or in other technical positions in the army, which sent people who the army selected for a technological or scientific aptitude into the high tech industry, already with experience. \nIn addition, a lot of the largest Israeli high tech companies were founded by people who gained some knowledge or another in the army, and then found a way to sell that knowledge in the civilian market ([NICE](_URL_2_), [Elbit](_URL_1_), [Rafael](_URL_3_) and more).\n\nMany of Israel's most successful institutions: banks, health insurance agencies, agricultural and industrial companies were founded as cooperatives, or within unions, with no profit motive and with the purpose of serving their members (rather than stockholders or executives) and developing the economy (Egged, Tnuva and Clalit are good examples of this).\n\nFor the second part, the universities in Israel were built early into it's history, with generous donations from north america and staffed with European academics that fled to Israel due to antisemitism in their home countries, many other institutions were also built with American and Canadian money and operated by European professionals."
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5f047v | Why communist countries produced some of the brutal totalitarian regimes of 20th century given that one of the core principles of the communism is shared ownership/ decentralisation ? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5f047v/why_communist_countries_produced_some_of_the/ | {
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"Might be better suited to /r/asksocialscience.",
"It was rather often that the Communist Parties that gained power weren't popular parties in modern and established economies choosing equality over the methods that developed them. Rather they were *Vanguard Parties*. The concept was something of a significant departure from earlier Communist Thought. Rather than socialist revolution coming from establish democracies and modern economies where the middle class overthrew the elite it was coming from places that hadn't yet gone through that stage. Which upended a lot of the assumptions of Communist Theory.\n\nSo, what is a Vanguard Party? Well, it's a smaller cadre of professionals, an elite if you will, who attempted to take control of a country that isn't entirely ready for end state communism and steer it to those ends. In the case of Russia it was a small group of hardcore professional revolutionaries and the people they trained. Really, this is a major point where Leninism diverges from Marxism. Given that the Soviets were the primary backer of all later Communist movements and given that they were the ones giving out training, guns, and money those willing to incorporate the Soviet ways of doing things were able to crowd out native communist movements.\n\nSo, Vanguard Parties were what happened. So, how did they end up very centralized rather than very decentralized? Well a bit one was bit of mental slight of hand. You see, the Vanguard destroys anything that is not the workers. The workers make up the nation. Therefore the nation is the workers. If the workers and the nation are the same thing then the nation owning the land is the same thing, right? But, in practice, it's this elite, enlightened vanguard that ends up owning the thing. After all, the workers aren't ready for direct control as they haven't gone through the whole process described by Marx's theories yet, going straight from rule of autocratic kings to the rule of \"the workers\" (and by that, they meant the Vanguard). \n\nA lot of the totalitarianism was theoretically justified by turning the workers into Homo Soveitcus, a fully modern and fully communist entity that would be ready for the socialist utopia that was inevitable in coming. This was understood as being as removing anything that was getting in the way. After all, if people don't have a choice but be that way then they will be that way... only, a lot of the Communal (read: State-Owned) enterprises and farms didn't work out as well. Soviet Agriculture, for example, was a disaster. The communal farms were never really able to produce as well as their western counterparts. This isn't an indictment of Russian Peasant, as the roughly 3% of farm land that was private plots produced about half of the nation's meat and fruit. The Soviets themselves figured that it was a lack of machinery that could take advantage of the larger scale of farms and a lack of infrastructure to distribute what was produced. At the same time western farms were consolidating in a similar manner, after all. In the United States factory farming was developing to get the most out of the various equipment being developed. It was hard for a small family farm to make use of a giant thresher, but with enough land a giant thresher can thresh much more cheaply than can be done by hand or even by smaller machines. So, the flaw has to be something other than just \"large, centrally managed farms are inefficient\" going on there. \n\nThere were several problems, so in addition to those that the Soviet leadership identified, there were things called agent-principal problems. In their dismantlement of Labor Unions they pointed out that the leaders of Unions often acted in their own interests despite their power coming from the workers. Basically, an agent-principal problem is any case where a person is empowered to make decisions for a larger group but acts in favor of their own values and goals and neglects those of the people they should be acting on the behalf of. Despite this accusation being leveled against the less political labor unions in the West, it's especially clear that it's what happened to these Vanguard Parties. If they were successful they became a new Aristocracy whose reason for existence was to bring workers to the point where they could own and rule in their own right and gathered all power to themselves to have the ability to make that happen. Though, they ultimately failed to make a great deal of progress because once they had all the power making decisions that would entail the loss of that power over time wasn't exactly the decision made. Once the Soviet Union blazed that path and richly rewarded anyone who followed it became the dominant mode of Communist expression throughout the century.",
"You may be interested in an answer I gave [here](_URL_0_) discussing the ideology of Soviet leadership towards classless/stateless societies. In short, though, Marxism only advocates decentralization during *communism*, not *socialism*, which is what \"communist countries\" were; they were socialist states trying to advance forward into communism. \n\nAs for authoritarianism, Marx and Engels encouraged such means. Engels wrote in 1872: \n\n > [Anti-authoritarians] demand that the first act of the social revolution shall be the abolition of authority. Have these gentlemen ever seen a revolution? **A revolution is certainly the most authoritarian thing there is; it is the act whereby one part of the population imposes its will upon the other part by means of rifles, bayonets and cannon — authoritarian means, if such there be at all;** and if the victorious party does not want to have fought in vain, it must maintain this rule by means of the terror which its arms inspire in the reactionists. **Would the Paris Commune have lasted a single day if it had not made use of this authority of the armed people against the bourgeois? Should we not, on the contrary, reproach it for not having used it freely enough?** Therefore, either one of two things: either the anti-authoritarians don't know what they're talking about, in which case they are creating nothing but confusion; or they do know, and in that case they are betraying the movement of the proletariat. In either case they serve the reaction.",
"I think you are almost hinting at the answer in your question. It is because the parties and states that called themselves communist or socialist were far from being so. I am going to stick to the Soviet Union while answering your question as it is the one I am most familiar with, perhaps the most brutal society and the one I suspect most here are most familiar with too.\n\nOf course, \"communist\" or \"socialist\" is a term, like many in politics, that has been so eviscerated of any meaning that it is difficult to use, but from its very earliest days the core of socialism or communism was democratic employee control and ownership of the workplace, or what Marx called \"workers' control of the means of production.\" That concept was entirely lacking in the Soviet Union, where control and decisions were made from the top down and there was little input from workers' councils. Stalin increased this by introducing [Edinonachalie](_URL_0_) or one-man management, where one official ruled the workplace and was responsible for virtually all decisions. These bosses were given presitge, power and very high wages, so much so that Stalinist statisticians were embarrassed that the ratio of workers' to managers' pay was higher in the Soviet Union in the 1930s than in the United States. \n\nThis top-down structure was mirrored in the parties themselves, which, as /u/a_soporific has mentioned, were vanguardist, meaning they saw themselves as the leaders of the state and expected obedience from subordinates. This is, needless to say, a highly authoritarian structure.\n\nTherefore, we should address why both these governments and Western governments continued to call them communist or socialist when they diverged so wildly from what was understood to be the core socialist principle. In the USSR, the government continued to call itself communist because of the very good light in which people (particularly working-class people) saw the concept. In the US, it was done for the absolute opposition reason: in order to defame the concept of socialism entirely, to associate it with authoritarian regimes.\n\nWe must also address the context in which communist governments like the USSR came to power. The Bolsheviks seized power after a devastating 3 year war which wrecked the society and the economy, to the point where starvation was widespread in Petrograd. There then followed an intense war where the British Empire, the United States, the French Empire, Japan, as well as host of other countries invaded Russia in order to \"strangle bolshevism in its cradle\", as Chuchill said. This led to further destruction of the country and to the new government developing under an all-out fight to the death against people inside and outside Russia who wished to destroy them. The society had not recovered when fascism rose around Russia's borders, in Germany, Japan, Poland and other states. one of the key messages of fascism was to destroy communism, and so Russia was dragged into preparing for another inter-contenental war of annihilation. Often historians portray the Soviets as paranoid, but their paranoia turned out to be justified. Stalin said in 1931 \"We are fifty or a hundred years behind the advanced countries, either we make good that gap in 10 years or they destroy us.\" Germany invaded 10 years later. \n\nIt is in this context that the decision of the communist governments were made: under threat of complete annihilation. They were seeming permanently at war and permanently in danger.\n",
"We can use Marx's own framework of historical materialism to answer the question.\n\nIn Marx’s theory of history, called historical materialism, society moves forward to new states, cultures, economic systems, etc. through a conflict between economic classes. A wealthy exploiting class, possessing property while the rest of the society use it but do not own it, is overthrown by the exploited class, creating a completely different socio-economic system. Marx’s definition of class is not based on things like income level, but whether or not one has any ownership of the means of production (factories, restaurants, stores, etc. and all other businesses). In one very critical phase of Marx’s historical timeline, capitalism has the function of modernizing and industrializing a society. This consequently creates a very huge sum total of wealth in a society despite the fact that the majority of the wealth is owned only by a very small section of the business-owning population. Socialism would follow capitalism as Marx argued, and it would improve upon the society by having the entire working class democratically control businesses allowing for a more equitable distribution of wealth (although not a perfect equality and not without material incentives for us to still pursue).\n\nMilovan Djilas, a Marxist critic of Communism from Yugoslavia, published *The New Class: An Analysis of the Communist System* in 1957. Djilas used Marx’s theory and progression of history to underline a fundamental problem: most or all of the societies that underwent leftist revolutions were not fully capitalist and even to a great extent feudalistic like Russia. As a result, Marx had been wrong on a key point of predicting that the advanced capitalist regions like North America or Western Europe were to be the first movers to socialism. In many of these new Communist countries the leaders themselves understood that their society was too backward and impoverished for socialism and so they developed their nation through an economic system called state capitalism – a term many believe best describes the nations we falsely call “Communist” whether past or present. The attempt to rush through this phase of Marxist history had failed as Djilas argued, and a new bureaucratic class had formed signifying a lack of democracy and socialism.\n\nDjilas goes in great detail to solidify his description of the “new class,” which involves them doing everything from using Marxism as a form of religious dogma to inflating their personal wages like CEOs in capitalist countries. As mentioned, the new class had formed because these societies based themselves on state capitalism to industrialize and modernize themselves. One critical aspect of this involved highly centralized planning to industrialize a nation more quickly than a market could, especially during Stalin’s rule and regardless of how much death and suffering was involved. Djilas explains that such intense centralization and capitalist behavior in the society gave birth to a bureaucratic and oligarchic class unaccountable to the vast majority of citizens living in Communist nations, a ruling class just like the slaveholders in ancient Rome, the land barons in medieval Europe, or capitalists in the United States."
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2n1i14 | From 1945 to 1990, how much independence did the Eastern Bloc states have? Were they capable of determining their own national policies independently of the Soviet Union, or did the Soviet Union pull all the strings? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2n1i14/from_1945_to_1990_how_much_independence_did_the/ | {
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"The message coming out of the Soviet Union regarding independent Eastern Bloc policies changed over time. When leaders first came to power in Moscow, they tended to announce that things were now different and that the Soviet Union would no longer interfere with the day to day business of its allies. Nikita Khrushchev and Leonid Brezhnev both argued as much, only to both famously call for an invasion of a Soviet shortly after (Hungary in 1956, Czechoslovakia in 1968). This is one reason that many in the West doubted that the reforms of Mikhail Gorbachev would lead to true independence in Eastern Europe, but when the Eastern European nations did start to rebel in 1989 he did not interfere as the Eastern Bloc fell apart.\n\nLooking at the specifics of the pre-Gorbachev invasions, the evidence of the limits of Eastern Bloc independence, we can see that Eastern Bloc states did have the ability to set their own national policies to a great extent. First lets look at the key difference between the invasion of 1956 and the invasion of 1968: in 1956, Hungary attempted to leave the Warsaw Pact altogether, to not only set its own domestic policy but also its own foreign policy. The invasion, then, does not really indicate the extent to which an Eastern Bloc nation could set its own domestic policy. In 1968, Czechoslovakia had no intention of leaving the Warsaw Pact but in fact renewed its commitment to the pact and to the Communist movement in general, as its reformist leaders continued to provide war material to North Vietnam. Yet even still, domestic policy threatened the Soviets and the other Warsaw Pact leaders enough to warrant an invasion. Before we look at the reasons why, lets look at the Eastern Bloc of 1968 a little more generally, because it was not just Czechoslovakia that sought its own path.\n\nThe leader of Poland, Wlydyslaw Gomulka, was not a Soviet first choice. He had come to power during the tumultuous days of 1956. Prior to that, he had briefly led Poland after WWII, only be removed from power by Stalin and his closer allies. During the crisis of 1956, the Poles themselves chose to return him to power as a reformer who could bring stability to Poland. The Soviets yielded because he was in fact an anti-German Communist even if he sought to liberalize Poland in ways that made them uncomfortable. In 1968, he remained the leader of Poland, although he had ceased the reforms he had previously sought. Gomulka was already one example of domestic independence; had the Soviets been \"pulling the strings\" like many imagine, Gomulka would not have been chosen in 1956. \n\nIn Romania, the Communist leader Nicolae Ceausescu had been at odds with Moscow since well before Czechoslovakia's Prague Spring. He had ceased to participate in Warsaw Pact activities, though he never threatened to leave the pact altogether. In 1968 he even condemned the Warsaw Pact's invasion of Czechoslovakia. It is important to note, however, that Romania was not as strategically important as Czechoslovakia or Poland economically or geographically, so you view Ceausescu's stubbornness differently because Moscow did as well. In any case, Moscow certainly did not pull the strings in Romania.\n\nNow on to Czechoslovakia and its Prague Spring of 1968, which led to the Warsaw Pact invasion Ceausescu condemned. Here we can see the full extent of Eastern Bloc independence (at least in the context of 1968) and where that independence ended. The Central Committee in Prague overthrew the Stalinist Novotny and elected the reformer Alexander Dubcek to power without interference from Moscow. Dubcek sought to implement massive economic and election reforms, and none of this bothered the Soviets much. Building on years of economic reform, this would have meant increased and eventually open trade with the West, as well as the introduction of a \"profit motive\" that would have allowed managers and workers to keep a large percent of their enterprises net profits. With election reform, Dubcek meant to allow the people of Czechoslovakia to play a more direct role in choosing their leaders and in designing domestic policy. Less famously, the Slovak Dubcek also sought to federalize Czechoslovakia and to allow the Slovak half a degree of autonomy, which obviously clashed with the Marxist-Leninist notion of the slow destruction of national identities. The Soviets were prepared to allow all of this. The problem arose with the lifting of censorship, as the rebellious writers of Prague began calling for the complete overthrow of Communist power not only in Czechoslovakia but in the Eastern Bloc generally. This sparked fears in the Soviet Union that in the absence of strict censorship Czechoslovakia would eventually leave the Warsaw Pact even if Dubcek was loyal to Moscow himself; moreover, it sparked fears throughout the Warsaw Pact that people in Hungary, in Poland, and perhaps even in the Soviet Union would soon demand that their own \"Dubcek\" came to power (a look at certain protest signs of the era reveals that indeed this literally happened). Dubcek continuously refused to reintroduce censorship no matter how hard the Soviet Union demanded it, and so Brezhnev eventually agreed with others that the Prague Spring should be put down by force. The knee-jerk reaction to this is to say \"look how little independence the Eastern Bloc nations had!\" A more nuanced analysis reveals that Czechoslovakia did in fact have an enormous amount of autonomy: it elected its own reformist leaders and put into practice their reforms. The Soviet Union only invaded after Czechoslovak initiatives threatened to undermine Soviet hegemony within the Eastern Bloc generally, and even then Brezhnev was strongly influenced by leaders in East Germany and Poland who feared they would be overthrown by their own domestic \"Dubceks.\"\n\n**IN SHORT**: No, the Soviet Union did not pull all the strings in Eastern Europe. Eastern Bloc nations had room for independent domestic policies. Moscow, however, would not allow these policies to threaten Soviet hegemony within the Eastern Bloc, and would use force to prevent a general collapse within Eastern Europe.\n\n*I have to point out that the concept \"Eastern Europe\" as it is used here was really a Cold War construct. Czechoslovakia was a \"Central European\" nation prior to the Cold War and that at one time meant something.*"
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4ocslc | why does microsoft word sometimes reformat half my document just because i hit enter or delete a space? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ocslc/eli5_why_does_microsoft_word_sometimes_reformat/ | {
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"This can be anything. You give it some guidelines in the formatting you do, and Word tries to format it as good as it can within the rules you give it. \n\nFor example when you put an enter or space that makes the last word of you paragraph not fit on the page, it would look silly to have only that word on the next page. So it will pull some extra lines with it. It's all meant to help you, and if it's not how you want you'll have to specify yourself (you can). \n\nGenerally postpone the formatting as long as you can, or just use LaTeX. ",
"The boring answer is that you've deleted a formatting character such as a section break, or you've caused an element in your document to get bumped to somewhere where it triggers a bunch of Word's other arrangement/formatting rules, potentially causing a cascade of fuckery.\n\nSome of the time it lets you do things that you shouldn't be able to (because of the problems it might cause later if you change something and it carries on trying to follow its own logic). It's flawed software basically, though that isn't to say that users don't create their own problems with it too."
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5qw3z4 | How much did Communist regimes support/resist feminism and feminists within their own country? | I'm most interested in the PRC, but I'd like to hear about others as well. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5qw3z4/how_much_did_communist_regimes_supportresist/ | {
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"In the years leading up to the PRC, Ding Ling was a very prevalent female author. In 1942, she wrote a piece titled Thoughts on March 8th (International Women's Day) which brought to light the sexism within the Communist Party. Specific examples she described included the relative difficulty of female comrades to get a divorce compared to their male counterparts, and persistent ideas that a woman's primary role was bearing children. Before publishing this Ding Ling had been well-regarded, even by Mao himself, but this criticism of the party and challenge of authority haunted her more or less for the rest of her life; 15 years later she was persecuted in the Anti-rightist campaign and variously exiled and/or sent to hard labor until 1979. \n\nThat's not to say the Communist Party was opposed wholesale to feminism. Earlier in the century, revolutionaries championed the abolition of foot-binding. Additionally, during the May 4th movement of 1919, when many of the male students protesting the Chinese government were arrested, it was young women who took their place protesting. So, it was more the affront to the party that got Ding Ling in trouble; if she had levelled the same criticisms at the culture of Qing-era China or even at the KMT or Japanese, she might have been fine. \n\nSource: The Gate of Heavenly Peace by Jonathan Spence ( & a class I took last semester on modern Chinese literature)",
"The PRC is a case I can't tell you much about but as far as I am aware, of the socialist countries in Europe only one had a significant feminist movement that went beyond very small circles, produces an actual counterdiscourse, and had a significant literary and theoretical output: Yugoslavia.\n\nFor background first: Communist parties and the 1st wave of feminism, i.e. the suffragist movement, had in the beginning of the 20th century despite similar political aims when it came to women, not always been on friendly terms. Classical Marxist-Leninist Communist had the tendency to understand of understanding issues of women's rights as a so-called side-contradiction, meaning that once the main contradiction of Capitalism, the class conflict, was solved, discrimination against women would end and a feminist movement would become unnecessary.\n\nThis however, was not a universally shared opinion. Rosa Luxemburg for example, early on, emphasized the importance of the struggle for women's suffrage and women's rights. In her 1912 article [Women’s Suffrage and Class Struggle](_URL_0_) she wrote:\n\n > There are many who, precisely on the basis of these facts, may underestimate the significance of the struggle for women’s suffrage. They may reason: even without political equality for the female sex, we have achieved brilliant advances in the enlightenment and organisation of women, so it appears that women’s suffrage is not a pressing necessity from here on in. But anyone who thinks so is suffering from a delusion. (...) One of the first great heralds of the socialist ideal, the Frenchman Charles Fourier, wrote these thought-provoking words a hundred years ago: \"In every society the degree of female emancipation (freedom) is the natural measure of emancipation in general.\n > \n > This applies perfectly to society today. The contemporary mass struggle for the political equality of women is only one expression and one part of the general liberation struggle of the proletariat, and therein lies its strength and its future. General, equal and direct suffrage for women will – thanks to the female proletariat – immeasurably advance and sharpen the proletarian class struggle. That is why bourgeois society detests and fears women’s suffrage, and that is why we want to win it and will win it. And through the struggle for women’s suffrage we will hasten the hour when the society of today will be smashed to bits under the hammer blows of the revolutionary proletariat.\n\nThis position, while finding some initial traction in the early Soviet Union disappeared again later, especially in the wake of the Stalinist \"social fascism\" thesis, which condemned all reformist undertakings as the seed of fascism.\n\nThis is important in as far, in the second half of the 20th century, socialist ruling parties in the concerned countries often perceived feminism, the then second wave, as a liberal and bourgeois undertaking and thus as counter-revolutionary. The path to women's liberation for them lay in their form of socialism and criticizing the status of women in their society was perceived as a movement or position that could only be inspired by revisionist and bourgeois thinking.\n\nThe onyl exception, as mentioned above, was socialist Yugoslavia. Yugoslavia had been different from the other kids form the beginning. Not only had Tito and the KPJ been able to secure their position and claim on legitimacy through their efforts in WWII and their liberation of their country from fascist rule by their own strength, but unlike countries like Poland or the GDR, the rule of the KPJ and Tito was not perceived as imposed by a victorious Soviet army but as the natural outcome of the country's struggle for liberation (basically, at least imposed by their own people).\n\nLegitimacy for socialist rule on Yugoslavia was built upon a narrative of the struggle for liberation and the Partisans. Transfiguring the Partisan struggle into the birth of socialist rule while at the same time portraying it as the natural expression of the new and socialist way society would work, it became the central element and narrative of Tito's rule, which ultimately allowed him to break with the Soviet Union and position Yugoslavia in the peculiar position it held for a long time: Not part of the Eastern bloc but socialist; socialist but without such a strict planned economy; a partly planned economy but with a large consumer goods industry etc. pp.\n\nThis is all important for the later appearance of a feminist movement in Yugoslavia because the narrative of national liberation and the Partisans could from its very inception not deny the important role of women. More than 100.000 women had served within the Army of National Liberation and the Partisan detachments. Those involved in the Anti-Fascist Front of Women (Antifašistiki front žena – AFŽ) counted around 2.000.000. Out of these, 600.000 were carried off to concentration camps (German, Italian, Hungarian, Bulgarian, Ustase), where around 282.000 of them died. In the course of fighting, 2.000 women reached an officer’s rank and many of them were elected members of the Anti-Fascist Council of National Liberation of Yugoslavia. After the war, 91 women were accorded the honor of National Hero.\n\nWomen who had participated in the struggle for national liberation were celebrated after the war and for the women who had served too, taking over professions from men and serving with a gun in hands established a place in the new socialist rule behind which the regime could not go back. In fact, the socialist Yugoslavian regime celebrated this narrative of equality within the Partisan movement (I say narrative here because the reality on the ground did sometime have the tendency of looking different in the sense of women in the Partisans being relegated to unimportant roles or some Partisan detachments not allowing women in the first place) and incorporated it into the new state.\n\nThis expressed itself in various ways, from the constitutional provision of Yugoslavia that women must be paid an equal salary, to Yugoslavia decriminalizing abortion in the 1950s, to the law concerning parental leave specifically instead of only maternal leave, to a concerted propaganda effort that highlighted female equality in film, literature and TV.\n\n\n\n\n\n\n\n\n\n"
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67f4la | why english distinguish between fingers and toes unlike other languages and what about thumbs? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/67f4la/eli5_why_english_distinguish_between_fingers_and/ | {
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"English has been a language that loves to get unique and specific names for everything, especially Old English. Finger, toe and thumb are all very old words. The main reason they have their own names is really because the language has placed an emphasis on finding a new word for something rather than mixing or combining words. You could call a thumb the big finger, but that is slower than the word 'thumb'",
"English is not the only language that distinguishes between them, although not all languages do.\n\nThere's no law saying that languages have to match each other exactly. Different cultures have different ways of classifying things. Russians just use the word \"palets\" to refer to an appendage on the end of a limb, and if necessary specify \"palets na noge\" (\"finger on the foot\") for a toe. Germans and English-speakers have a word used for appendages used to manipulate, appendages that make gripping possible and appendages for walking on. The French can use their word for \"finger\" to refer to toe if the context makes it clear, but have another, different word they can use instead."
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ahc3c6 | Subway fallout shelters? | In the "Metro" series of novels by Dmitry Glukhovsky, the vast majority of human survivors of a nuclear apocalypse take shelter in the Moscow metro tunnels. Was this kind of measure ever floated either in the US or USSR as a credible method of surviving a nuclear strike? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/ahc3c6/subway_fallout_shelters/ | {
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"The Moscow subway system was considered for use as bomb shelters as early as World War II (against conventional weapons). They were also extensively studied for use as nuclear blast shelters in the Cold War. It should be noted that by the Soviet's own estimations, the subways were not large enough to shelter the entire Moscow population; they could accommodate maybe 530,000 or so (out of a metro area of several millions), assuming you had adequate warning to move people down there. \n\nIn the USA, I don't know of any subway metro systems that were specifically designed for this task, though the vaulted ceilings of the central Washington Metro system have been noted in contemporary discussion of public shelters as being pretty good for blast pressure support. (The New York City subway system, by contrast, was clearly not specifically developed with this in mind — it is much older on the whole — but any underground shelter is probably better than any above-ground shelter, the deeper the better.) I have not seen any indication that planning for subways in the US was ever bent towards the aim of being better shelters than they might be by default (which would involve \"hardening\" design decisions at the very least, storing supplies and careful ventilation choices at the most). But many discussions of urban Civil Defense in the USA did (and still do) talk about subways as one of many possible ad hoc shelters against blast or fallout. Again, as with the USSR, while US subways seem to be endlessly cavernous and accommodating, they could, even with lots of warning time, only accommodate a fraction of the total population of a dense urban area (as anyone who has been in these systems during rush hour knows quite intuitively!).\n\nOn the Moscow subway shelter estimates, see Edward Geist, \"Was there a real 'mineshaft gap'?: Bomb shelters in the USSR, 1945-1962,\" _Journal of Cold War Studies_ 14, no. 2 (Spring 2012), 3-28."
]
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4d8w9l | air resistance and newton's second law | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4d8w9l/eli5_air_resistance_and_newtons_second_law/ | {
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"What's your question? \n\nNewton's 2nd Law states that the acceleration of an object is dependent on the net forces acting on the object & the mass of the object. Air resistance is part of those net force."
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es6fds | extra chromosomes | Why is it that having more chromosomes makes you have physical and mental problems? I get that having less than the correct amount could mean missing info and stuff but why does extra cause problems? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/es6fds/eli5_extra_chromosomes/ | {
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"Extra chromosomes would cause problems when our DNA and cells replicate. It would cause misalignments of DNA during cell separation, causing one cell to get extra copies and others to acquire none, or even cause DNA breakage events. These may render DNA unusable and may break crucial sequences that are required for normal functioning. Extra chromosomes that actually do work may cause protein imbalances which also affect basic cellular and/or organ functioning.",
"DNA, which is arranged in chromosomes is the blueprint for building a person. It's like a recipe. Imagine you're baking a cake and it tells you to add 3 eggs. Now let's pretend there's a misprint in the cookbook and it says to add 6 eggs. Your cake is going to come out messed up if it even comes out at all, right?",
"To add to all the great analogies, in most cases having an extra chromosome or missing one is not compatible with life and would lead to a miscarriage very early on in the pregnancy. In fact, most women who miscarry never knew they were pregnant. \n\nOnly a very select number of these mistakes can produce a viable fetus. The most common being trisomy 21 (down's syndrome)"
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2864j6 | How did British civilians react to losing the Revolutionary War? How did they take the news? How was it broken to them? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2864j6/how_did_british_civilians_react_to_losing_the/ | {
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"Interestingly, though it doesn't directly answer your question, the British people were presented images of Cornwallis surrendering his sword to General Washington. [A painting by John Trumbull of the same name hangs in the Rotunda of the Capitol](_URL_0_)\n\nHowever Cornwallis didn't actually meet Washington and surrender. On October 19, 1781 he called in sick and sent his aide-de-camp Charles O’Hara with the sword. Washington refused to take it and sent his aide, General Benjamin Lincoln, to collect it.\n\nSo to some extent, the British people were presented a lie in this case. Cornwallis did not behave honorably according to protocol.\n\nSource: Ferling's \"Almost a Miracle: The American Victory in the War of Independence\"\n\nIn fact, in spite of behaving dishonorably at the surrender of Yorktown, Cornwallis did not go down in shame and ignominy. The king still favored him and the new Prime Minister, William Pitt, held him in esteem. He was made a Knight Companion of The Most Noble Order of the Garter in 1786.",
"To add to the question, I learned in high school history class that the English actually organized Betting poles in which they gambled on when the the post- revolution United States would collapse (apparently done somewhat prolifically). Is this supported by any scholarly or academic sources? ",
"Firstly, remember that there was no universal opinion in Britain at the time - many people supported the Amercian rebellion. As well as prominent Whig politicians like Charles James Fox, David Hartley, Thomas Brand Hollis, Sir George Savile, John Wiles and Edmund Burke, many ordinary people showed support as well. \n\nGroups like the pro-Amercian London Association approved an anti-war petition to be presented to the government, though this was shelved. \n\nThere were also dissenting clergymen such as Josiah Tucker, the Dean of Gloucester, Francis Blackburn, John Jebb and John Horne Tooke, who reportedly made the anonymous charge in a London Newspaper that Americans has been \"inhumanely murdered\". The Reverend Richard Price released a pamphlet called, Observations on the Nature of Civil Liberty, the Principles of Government, And the justice And Policy of the War with America. \n\n_URL_4_\n\nThis sold over 60,000 copies.\n\nThe British Press was the freest in the world at the time and those printed in London had the largest readership. Solomon Lutnick performed a study of attitudes in the British Press.\n\n_URL_3_\n\nHe found that the Morning Chronicle, the London Advertiser, the Courant and Westminster Chronicle were against the government, and the London Gazette, the General Evening Post and Lloyd's Evening Post were supporters. Such devisions were replicated in the provincial press.\n\nColin Bonwick's English Radicals and the American Revolution provides further insight.\n\n_URL_2_\n\nMuch of this was driven by Englightenment ideals, popular amongst the coffee houses of the time, but there was also a decline in trade during the war. In 1779 English exports were the lowest since 1745. With trade so vital to Britain at the time, there was a hope that the end of the war would allow for peaceful trading relations. In fact, despite losing its trading monopoly, Britain's level of trade quickly restored to pre-war levels.\n\nSamuel Johnson, the prominent Tory writer of one of the most influencial dictionaries in history, in his anti-rebellion pamphlet Taxation No Tyranny of 1772, forsaw the possibility of losing the American colonies, but hoped that in this case, trade would still be possible:\n\n > We are told, that the subjection of Americans may tend to the diminution of our own liberties; an event, which none but very perspicacious politicians are able to foresee. If slavery be thus fatally contagious, how is it that we hear the loudest yelps for liberty among the drivers of negroes?\n\n > But let us interrupt awhile this dream of conquest, settlement, and supremacy. Let us remember, that being to contend, according to one orator, with three millions of whigs, and, according to another, with ninety thousand patriots of Massachusett's bay, we may possibly be checked in our career of reduction. We may be reduced to peace upon equal terms, or driven from the western continent, and forbidden to violate, a second time, the happy borders of the land of liberty...\n\n > If we are allowed, upon our defeat, to stipulate conditions, I hope the treaty of Boston will permit us to import into the confederated cantons such products as they do not raise, and such manufactures as they do not make, and cannot buy cheaper from other nations, paying, like others, the appointed customs; that, if an English ship salutes a fort with four guns, it shall be answered, at least, with two; and that, if an Englishman be inclined to hold a plantation, he shall only take an oath of allegiance to the reigning powers, and be suffered, while he lives inoffensively, to retain his own opinion of English rights, unmolested in his conscience by an oath of abjuration.\n\n_URL_0_\n\nAfter the war was lost, there was definitely a feeling of immediate reconciliation. In this cartoon of 1782: \n\n_URL_1_\n\nIt expresses the idea of America as the daughter reconciling with her mother, Britainnia while other nations try to pull them apart.\n\nAfter the war, the pro-Grovernment press tended to concern itself with two issues: the money that Americans had borrowed from British merchants before the revolution, and the property that state governments seized from Loyalist exiles after independence. There were also criticisms of the weakness of the American government under the Articles of Confederation when it was seen as being impossible to negotiate treaties with a Congress which did not yet have the power to enforce them.\n\nOverall then, those that supported American Indpendence were pleased that the North Administration had lost, and those that supported the government, whilst critical of the new country, wished for normalised peaceful trading relations as soon as possible.\n",
"Wow! Thanks to all the submissions! Just a couple more questions:\n\n* Were people angry they lost, or was it just a \"whatever, good for them\" kind of ordeal?\n\n* What happened in the trade industry after the war? Did the newly founded America have trouble importing and exporting materials?"
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"http://upload.wikimedia.org/wikipedia/commons/4/4d/The_reconciliation_between_Britania_and_her_daughter_America.jpg",
"http://www.jstor.org/discover/10.2307/1877433?uid=3738032&uid=2129&uid=2&uid=70&uid=4&sid=21104152140367",
"http://books.google.co.uk/books/about/The_American_Revolution_and_the_British.html?id=yjhCAAAAIAAJ&redir_esc=y",
"http://oll.libertyfund.org/titles/1781"
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6gr0tf | why do tv shows use identical twins to portray one character? | For example, Michelle Tanner in Full House was portrayed by Mary Kate and Ashley Olson or Jamie from Malcom in the Middle was portrayed by James and Lukas Rodriguez. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6gr0tf/eli5_why_do_tv_shows_use_identical_twins_to/ | {
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"The common thread in your examples is that the characters are **children**. Children are not great actors. They are hard to direct on a set. Depending on age, it can even be hard to get them just to do or say what the script requires. Additionally, children have short attention spans and get tired quickly.\n\nWhen you have a pair of twins, you get more opportunities to do repeated takes until you get it right.",
"There's a lot of laws around child labor. It's largely banned in many industries but exceptions are made where it's unavoidable, like child actors. Even there, there's a lot of requirements & regulations about working hours & conditions. There's no good way to deal with limited working hours & make a child a major character in a show without having two of them."
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34wiis | where does the bulk of our knowledge of ancient rome come from? | I've heard that most of the historical records were lost during the Great Fire of Rome in 69AD but I haven't really been able to turn up much reliable info on the net. I would love to hear from an expert. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/34wiis/eli5where_does_the_bulk_of_our_knowledge_of/ | {
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" > I've heard that most of the historical records were lost during the Great Fire of Rome in 69AD\n\nI think you're confusing this with the loss of historical records during the [Gaulish sack of the city in the early 300s BC.](_URL_0_) Sources for the period before that disaster are, in fact, very scarce. Even secondary sources, like Polybius and Livy, don't seem to have much clear information about events in Rome before the sack.",
"I'll try to provide an overview, seeing as nobody else has.\n\n* Literature - a large body of literature (in Latin and Greek) from the Roman period survives; the fire (actually 64 AD) didn't really affect that to my knowledge, as there was more than one copy of each work. As someone else mentions, there is more of an issue with the Gallic sack c. 390 BC, before which our knowledge is very limited. But from the \"historical\" period, especially from the first century BC onwards, we have histories, geographies, encyclopedias, speeches, philosophies, poetry, grammatical works...all sorts really. We don't tend to have \"originals\" of these works - they survive through copies made by monks in the Middle Ages. The discipline of ancient history is mainly concerned with the study of ancient texts, as opposed to...\n\n\n* Archaeology - the study of material culture. The Romans left a huge amount of material behind to be studied, from the Colosseum and Hadrian's Wall to the fragments of pottery being excavated all the time. Archaeology can often tell us more about everyday life for ordinary people than literary texts, which tended to be written by rich men, and can confirm (or challenge) the literary sources mentioned above. Archaeology can also include art and architecture under its umbrella, although art history is often studied as a separate discipline.\n\n\n* Epigraphy - the study of inscriptions. The Romans produced a staggering number of inscriptions, of which hundreds of thousands survive, with more being discovered each year. Whilst they tend to be shorter than literary sources, inscriptions have the advantage of surviving as \"originals\" rather than medieval copies. All sorts of things were inscribed: laws, gravestones, religious dedications, etc. Inscriptions can vary greatly in their scope - from those badly damaged by the effects of time, so that only a few letters are now legible, to something like the [*Res Gestae Divi Augusti*](_URL_0_), the bilingual autobiography of the emperor Augustus which was inscribed throughout the Roman world.\n\n\n* Numismatics - technically a branch of archaeology, this is the study of coins, one of the most commonly excavated types of item. Coins are useful for economic history: the quantity of precious metal in them can reflect the state of the economy at their time of production, and their distribution can indicate the extent of trade routes.\n\n\n* Papyrology - In Egypt, the dry climate means that many documents written on papyri have survived.\n\n\nThose are the main types of sources available to ancient historians, archaeologists, and classicists. I'd be happy to answer any follow-up questions."
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2efxqj | why is it that when we first wake up, our eyes don't work very well? i don't mean the re-adaptation from darkness into the lit environment, i mean that our sight is really bad even moments after adapting to the light. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2efxqj/eli5why_is_it_that_when_we_first_wake_up_our_eyes/ | {
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"Film builds up on your eyeballs overnight. It has to be rinsed off by your tear ducts. "
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79ovti | [Physics] if I peeled off two random stickers on a rubix cube and replaced them with each other, will the cube still be solveable? | Also, where do I post this question | askscience | https://www.reddit.com/r/askscience/comments/79ovti/physics_if_i_peeled_off_two_random_stickers_on_a/ | {
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"One obvious case where the answer would be \"no\" is if you randomly swap a center square for a differently colored corner. In that case, you'd end up with two faces that would need to be solved for the same color, which is impossible.",
"This isn't really a physics question, but since I have been solving Rubik's type puzzles for four years I would say I'm qualified to answer this. \n\nIn short, the answer is no. Unless of course, you consider that the two stickers being swapped is the new solved state. \n\nAlgorithms that are used to solve the Rubik's cube translate and rotate pieces but the pieces always maintain the same sticker configuration. \n\nYou can, however, rotate three corners in the same clockwise or counterclockwise direction and it will be solvable. You can flip an even number of edge pieces around and still be solvable. But you can not switch stickers of different colors and have it be solvable. \n\nAnd you could probably have asked this question on a Rubik's cube Reddit page. I bet there are a couple out there. You have have other questions, feel free to PM me."
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4bcuav | ; why is the qwerty keyboard configuration slower than the alphabetical form? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bcuav/eli5_why_is_the_qwerty_keyboard_configuration/ | {
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"It isn't that they specifically typed faster. It is that certain letters that are used frequently in combination were typed too fast...causing them to lock together in typewriters. They needed to move the letters that go together often to places on the keyboard that won't cross and get stuck.\n\nWe type just as fast with qwerty. It is just that certain letters rarely get typed in succession that would get locked together.\n\n",
"QWERTY was introduced to put letters that are used most not too close together so the parts that strike the tape in the machine wont intersect while person is typing fast. ",
"Manual typewriters required some finger strength to press the keys. QWERTY was invented so that the keys you press the most are near your strongest fingers. They could have done a better job of this, but they didn't because of the reason you mention. Another configuration called DVORAK is superior, but it hasn't caught on.",
"QWERTY has more to do with letters next to each other being pressed at the same time, and less with speed.\n\nWith a typewriter, if you press 2 keys next to each other (same row) at nearly the same time, they can collide, bind, and get stuck or even break. QWERTY was designed because letters commonly used in sequence are placed on separate lines.\n\nABCDEF configuration is not optimized for typing. That's the reason \"DVORAK\" was developed. It places keys in a way where the most used ones are most easily accessible. This requires less movement, and thus, faster typing.\n\nKeyboards don't bind, and the need for QWERTY no longer exists, but it's stuck around just because typists learned it and never went back. People are used to it. It's not the best, it's just the best known."
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28el6t | What can you tell me about the Allied counterinsurgency operations against the Nazis after the end of WW2? | i'm specifically interested in the US operations, and how the tactics employed may have differed from how the US conducts those types of operations now. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/28el6t/what_can_you_tell_me_about_the_allied/ | {
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"I'm not quite I understand what you mean.\n\nThe \"counterinsurgency\" that was carried out was nothing more than conventional mopping up operations, sometimes not being more than a platoon of soldiers facing off against a lone sniper. The Nazi \"insurgency\" that existed after the war was nothing more than a bunch of uncoordinated fanatics and was never a practical threat beyond theory. There were plans made up on how to deal with a possible insurgency, but since an actual insurgency failed to materialize, they were not actually put to use.\n\nSince I am not close to as well-read on the Eastern Front as I am on the various other fronts, perhaps one of our experts on here can enlighten us how it looked on the Soviet side?"
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2jzy1q | why don't the jehovah's witnesses churches have any windows? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jzy1q/eli5why_dont_the_jehovahs_witnesses_churches_have/ | {
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"They are called \"Kingdom halls\" not churches. Also, the ones I have been too have windows... ",
"As far as I know, historically vandalism of JW Kingdom Halls has been decreasing over the years. Starting at the end of WWII it was quite bad, and gradually has reduced to where it is today.\n\nThe older the structure, the greater the probability that it has no windows to reduce the likelihood of vandals breaking in and causing more significant damage. I suspect that the standardized blueprints for new construction were not adapted to include windows until the last couple decades. Remodels likely still exclude windows due to the cost of adding windows where they have not been.\n\nWindows aren't needed though. Kingdom Halls have plenty of interior lighting. Also, many churches have stained glass windows with depictions of some saint or VIP, but JWs don't agree with the worship of idols or images and therefore do not use stained glass windows in their architecture. It certainly is less expensive to build and maintain that way! Much easier for a donation-based organization.",
"many of them do have windows. just do a google image search for 'kingdom hall'\n\n\nthey are also built quick, usually over the period of one or two weeks, so not having windows saves time and construction expense. also it's one less thing to have to repair if someone breaks them.\n\nAll their meetings are open to the public, so it's not like there is secret stuff going on inside that they don't want people to see"
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44kcr4 | if water has no nutrional information how does it support life to function? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/44kcr4/eli5_if_water_has_no_nutrional_information_how/ | {
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"You are 60% water, and you use it up everyday to maintain bodily functions, like breathing and other important shit. So technically, you have to replace it by consuming more water.",
"Water is an excellent solvent. Our body chemistry depends on thousands and thousands of different molecules being able to interact freely in a liquid; and water is both common and effective. As humans, we have evolved with the assumption that a certain amount of fresh water would be available to take in each day; so we use up that amount of water in other ways (exhaling water vapor/droplets, sweating, urination). Animals which live in environments with much less available water have evolved to use water much more carefully; some small animals excrete so little water that they get enough from the seeds they eat and never have to drink liquid.",
"Water is polar and allows a lot of reactions to occur within it. Also a lot of carbs and sugars are basically made up of water I believe the basic formula of it is CH2O so water in one way or another makes up a lot of important molecules that support life and the reactions needed to provide life. ",
"Your cells are mostly water, encased by a membrane. Between your cells is water and there's always a balancing act that takes place to keep these levels relatively constant. All of the processes that take place inside a cell, including the breakdown of energy substrates (sugars, proteins, fats), movement of ions, nutrients, wastes, etc... take place within the cell's water, and between the cell and the water outside the cell. Without water then, the processes that keep cells alive would cease.\n\nIt's not that it provides nutritional value, water is what allows cells to process nutrition and perform their functions. ",
"Blood is mostly water. It carries oxygen. Muscles are 75% water. Besides supporting the skeletal system, smooth muscle propels food through our system. It lubricates joints. Allows our kidneys to filter blood. Flushes out waste. It's released even when exhaling, but is needed to maintain blood pressure and body temperature. Other drinks (as well as foods) will do the same job because, they too, are mostly water. The exceptions lie in salt water (lost at sea mistake!) and alcohol (lost at sea mistake?). "
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9j7b43 | salt lamps?? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9j7b43/eli5_salt_lamps/ | {
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"They provide some light, and they look sort of cool.\n\nThere is absolutely no evidence they have any effect on your health."
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65fwao | why did slavery in the 1800s only exist in the agricultural economies of the south and not the industrial economies of the north in the us? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65fwao/eli5_why_did_slavery_in_the_1800s_only_exist_in/ | {
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"Because oddly enough holding slaves was pretty expensive and in the north there were hordes of immigrants that would work themselves almost to death for almost no money at all. Also, tradition. ",
"Part of the reason was the explosion of industrialization in the Northeast. Large factories don't need slave labor to prosper, whereas massive plantations do. It's purely economics. \n\nThe wealth of the south was entirely dependent on agriculture which needed cheap labor, not to mention people who wouldn't need their own houses, which is a major waste of valuable farming land. \n\nMeanwhile, the north developed industry that didn't depend on slaves to survive. A large part of this disparity is geography. Not only is farmland in the north not as productive as the south (shorter seasons), but industry of the time was almost completely powered by water. Narrow, fast-running rivers were ideal for factories, and the Northeast has those in spades."
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30ee93 | How accurate is the portrayal of Italian colonial activities in Libya in “The Lion of the Desert”? | -In the film, the Italian colonial authorities round the Bedouin population into concentration camps, use poison gas, and execute civilians. I am aware these events are broadly accurate, but does the film exaggerate any specific incidents? Or is it a largely accurate portrayal?
-After Mukhtar is captured, he is brought back to an urban center (I think it was Benghazi but the film doesn’t specify), where there are many Italian settlers. How large was the Italian population in Libya? What was their experience during this period?
-Fascist imagery is prominent on many of the uniforms of the Italian soldiers. Did Mussolini really integrate this kind of imagery into military uniforms?
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/30ee93/how_accurate_is_the_portrayal_of_italian_colonial/ | {
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"Hello, I apologize for the late answer, I hadn't seen this post until now. This film does actually have a lot of accurate aspects to it, and the uniforms are portrayed surprisingly well (in some aspects, which I'll get more into later). It's interesting to note that this film was banned from Italian viewers until 2009. It was controversial in how it portrayed Italian occupiers of Libya to be rather ruthless, however, there is quite a bit of truth to this portrayal.\n\n\n\n\nWith regards to the concentration camps, I believe the movie was attempting to portray the camp at El Agheila (it's been a while since I've seen the movie, but I can't quite remember). There was indeed a forced migration of an estimated 80,000 Bedouins into these camps of which many thousands died. I have not seen any accurate figures proposed, just rough estimations. We can assume though that the populations inside were malnourished. I'm not sure if you realized this while watching, but the aerial footage of the camps is *real* footage taken from the Regia Aeronautica. It wasn't a set, but that was actual footage that Akkad worked into his film. As for the gassing and executions, I cannot say for certain if this did or did not happen. The idea behind these camps were to isolate and cut-off local support for Mukhtar and his resistance movement. The goal really wasn't to exterminate the Libyans as is often associated with concentration camps of this nature. MVSN (the soldiers displaying clear fasces collar tabs) did investigate and monitor these interned civilians, executing those suspected of resisting occupation. I'd hesitate to say that Italian soldiers were held to a higher standard than to resort to war crimes, because it is known that Graziani and Badoglio (Italian general and Governor of Libya at the time) had no problem gassing urban areas in Ethiopia a few years later during the 2nd Abyssinian War.\n\n\n\n\nBenghazi did have a large Italian population, and by the time of Mukhtar's trial, was seeing a large influx of Italian settlers. It's important to note that Mukhtar's resistance lasted *20 years.* Many Italian industries were beginning to move into the colonies and Benghazi, Tripoli, and Tobruk were the ports they would come in through. So naturally, these cities were the largest influx of Italian settlers. Benghazi specifically had a large concentration of Jewish Libyans (and importantly in favor of Italian occupation), so this city became a central location for Italian settlers to integrate into the colonies. At the time the movie was portraying, which was Mukhtar's trial and execution, Benghazi would have been in the process of the build-up campaign. In the early 1920's governor generals Volpi authorized a unique architectural campaign in Benghazi which to this day are still popular tourist attractions. This architecture is referred to as a \"Western interpretation of Eastern culture,\" and commonly known as *The Volpi period.* The designers used Moorish motifs, complimented by a grandiose fascist style. Volpi brought in Armando Brasini, a prominent Italian architect to create massive and impressive buildings in this style to compliment Volpi's *lungomare,* a walkway path along the sea that is still to this today, one of Benghazi's must see tourist attractions. In addition to this and Governor Italo Balbo's assimilation campaign, there were an estimated 20,000 Italians in Benghazi in the early 1930's, so the portrayal of Benghazi in the movie is quite accurate to how it would have looked.\n\n[Source](_URL_0_) \n\n\n\n\nThe uniforms are surprisingly accurate in the movie. The soldiers displaying the fasces are MVSN units, also known as \"Black Shirt Battalions.\" These are Mussolini's Black Shirts that were very active in the Libyan occupation and campaigns. Their colonial uniforms are quite accurate, their insignia is indeed a black collar tab with fasces pin over it and a fasces *fregio* (insignia) on their caps, which were the Alpine styled cap (without feather) and were used before the MVSN switched to bustina. There are a few historical inaccuracies with the uniforms in the film, most prominently in the weapons they used. A lot of the machine guns were American and British, understandably as Italian firearms of the era are rare and hard to come by. A few non-carcano's being used here and there, but minor criticisms. There is also an Alpini soldier (Italy's elite mountian trrops) featured towards the end the movie in a continental Grigio-verde colored uniform (grey-green that the Italian army looooooved to use on everything), but there were no Alpini in Africa at that specific time. Graziani is portrayed very very well, as is Mussolini. In fact, Stieger (the actor portraying Mussolini) actually found Mussolini's real life barber, and had him give him a Mussolini style shave/haircut and tell him stories about his mannerisms, what he was like, etc. and used this in his portrayal of the film. A very neat story and well-done rendition of Il Duce.\n\n\n\n\nMussolini did want his soldiers to be dressed professionally and basically advertise for him. This was his mentality, to advertise fascism. He loved parades, military marches, grand fascist celebrations, and he wanted to impress. When he conquered a country or city, or island, he wanted to have large parades in the streets where people were impressed and want to be a part of the Italian empire. He didn't want to simply exploit colonies, he wanted them to *want* to be a part of Italy and this surprisingly worked pretty well in Libya. In 1911, Mukhtar had widespread support and people were resistant to Italian occupation. By the 1930's, many Libyans willingly enlisted in the Italian askari corps. Now, of course there were benefits for bedouins and native populations to enlist, but Libya was to some degree effectively assimilated into Italy as well. In fact, it was a Libyan Savari serving in the Italian military that caught Mukhtar. Italian Savari's were often murdered and tortured by Mukhtar's men, along with their families. While many opposed Italian occupation, there were many that embraced it and the modernizing (at least to some extent) of their country\n"
]
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[
"https://books.google.com/books?id=PqqGAgAAQBAJ&pg=PA17-IA55&lpg=PA17-IA55&dq=lungomare+Benghazi&source=bl&ots=vrKQ3Wd1Pu&sig=COXZbIOXbFKk_JkKm-oKU0N2Bwc&hl=en&sa=X&ei=PMMWVeTGIM_YggTR0IM4&ved=0CFAQ6AEwCw#v=onepage&q=lungomare%20Benghazi&f=false"
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|
4fdao2 | What are the differences between Fiberglass and Refractory Ceramic Fibers? | As far as I can tell, both are made from aluminosilicates. Does it just depend on the size of the fiber? What makes one hazardous and the other less so?
I'm trying to tell the difference between something like E-glass/S-glass, and RCF's. | askscience | https://www.reddit.com/r/askscience/comments/4fdao2/what_are_the_differences_between_fiberglass_and/ | {
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"You are correct, the manufacture of the two is only slightly different and causes fiberglass to have long fibers and RCF's to have short fibers. [Source](_URL_1_)\n\nAs far as health risks go, I scoured the literature and there really isn't much on RCF and fiberglass is known to cause mild irritation to skin and respiratory tracts. [Studies done on the relationship between carcinogenicity and particle dimension show that long, thin fibers are the most likely to cause cancer](_URL_2_). [And a study comparing RCF and fiberglass (amongst other mineral fibers) show that both materials can be carcinogenic](_URL_0_). In short, inconclusive, what's the answer you're given? My instinct tells me its fiberglass because the material is more abrasive than mineral wools. "
]
} | [] | [] | [
[
"http://www.ncbi.nlm.nih.gov/pubmed/9707503?ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum",
"http://www.madehow.com/Volume-2/Fiberglass.html",
"http://jnci.oxfordjournals.org/content/67/5/965.abstract"
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|
5n8cl5 | How is it that we can smell heat? | Right now I just moved into a new room which was left unheated. There's only one radiator on the other end of the room from where I'm sitting and although I turned it on, it's still very cold in the room. However, I can "smell" the heat coming from the radiator. How does this work? The smell is usually always the same with most radiators. Can we even smell temperature changes? | askscience | https://www.reddit.com/r/askscience/comments/5n8cl5/how_is_it_that_we_can_smell_heat/ | {
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"What you're smelling is not \"heat\", but the effects of heat (Burning, Cooking Melting, etc.). There are multiple things that can cause the \"smell of heat\".\n\n\n* When a heater is not is use for a long period of time, dust collects inside the vents. When the heater is turned on, the dust burns off and emits an odor.\n\n* The heat strips in your air handler may activate when an extreme change in temperature occurs to help heat up the place quicker. These strips may also have dust on them creating the burning smell.\n\n* Heat will usually \"amplify\" smell due to the heat making the item emit more 'smell particles'. You can see this in cooking. So that smell is most likely the burning of something, whether is be dust or metal.\n\n* Burning metal, or the inner workings of a heater, will release traces of gas that burn up releasing odors as well. [Info Here](_URL_0_)\n\nHope this helps. I don't know much about this kind of stuff, I just asked my aunt who works for an AC company. "
]
} | [] | [] | [
[
"http://www.ccohs.ca/oshanswers/safety_haz/welding/fumes.html"
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76wm3t | how does advertisements actually profit? i find it hard to believe that they actually cover the cost that it took to run. | For example, a holiday inn running a commercial. Surely that commercial is not convincing anyone to go stay at a holiday inn. Or a ford commercial, how many people out there are actually convinced to buy a ford truck by watching a commercial? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76wm3t/eli5_how_does_advertisements_actually_profit_i/ | {
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"Advertising has really helped some products. This has been shown time over time. Therefore advertising agencies exist. They use these examples to prove their worth. Company executives believe them. They believe them implicitly. \n\nThey also believe in the secondary benefits of an ad or an ad campaign. After a while the company executives believe in getting their name out, in being present. They just want you to know that they are in the world so you will select their company when you have a choice.\n\nI haven't owned a Ford ever. But I considered one when making my selection.",
"So while there are obviously going to be situations where the amount of money gained from an advertising campaign is less than what you spent on it, overall you make more money putting more money towards advertising campaigns by bringing in more sales. \n > Surely that commercial is not convincing anyone to go stay at a holiday inn. Or a ford commercial, how many people out there are actually convinced to buy a ford truck by watching a commercial?\n\nYou're problem seems to come from assuming that people aren't affected by advertising or able to have their habits swayed whether consciously or subconsciously which is obviously not the case. There has probably been more money and research put into advertising and it's effectiveness than almost anything and they are constantly researching how to make it more effective. \n\nAs far as your example, while the commercial probably won't make you decide to run out and take a vacation and stay at a Holiday Inn, but it could easily put the brand in your head so you'll choose it next time you do or they may be running a special that works perfectly for your next trip or one of your employees. \n\nAs far as Ford, you are forgetting that there is always a sizable chunk of the population that is in the market for a new car and seeing the design of the new Ford truck or seeing what financing deals are available may be enough to push you to go with the Ford rather than the Chevy. \n\nFor stuff that is so ubiquitous that it seems pointless to have advertising anymore such as Coca Cola or McDonalds they are normally literally just trying to remind you of the product, keep it on your mind and maybe push you to crave it or cause you to associate it with a certain thing that will push you to consume more, such as a commercial that does nothing but remind you how great Coca Cola goes with a burger. ",
"The purpose of an ad isn't to convince you to buy what they're selling. It's to let you know that they're selling it. ",
"Yeah they do. There are metrics they run. Some ads work and some don't. That is where an agency comes in. They do all the market research on what should bring new customers in your door. So lets take Holiday Inn for example. Not every ad is big budget. Some are small low cost and some are high dollar budget. Each one serves it purpose. Large expensive campaigns are about brand awareness. So when you think hotel the first name to pop into your head is Holiday Inn. These will be run at regular intervals during high rated prime time shows. They will be shocking usually with humor and will probably avoid the color red and have a lot of bright colors that complement blue but will many be greens and yellow tones. If watching TV in a dark room the commercials usually light up the room with its tones. Each camera angle change creates a dynamic tone change to mimic the effect of a police light. Attention, attention. The blue complimentary tones in such a manner are exciting but somewhat calming. Trusting tones. If its a lawyer ad for a accident lawyer. They will often do the opposite. Complimentary tones to red. Showing power, and dominance. So Holiday Inn is planting a seed in your brain that they are exciting, trustworthy, flashy but safe. Than they have the upkeep ads. Shorter less flashy, hardly any humor. They might be just their logo on billboards, 30 secs calm ads at less watched times on tv where they pay a channel X amount of dollars to show X amount of times in a specific date range of their choosing. That isn't about brand recognition but to just remind you over and over. Holiday Inn express. Holiday Inn Express. The hardest part of a business is getting new customers. New customers are the life blood of any business. And they are worth a lot. You are looking at each potential customer as being only worth their visit. But its considered so much more than that. Im going to give a hypothetical situation of their value. Lets say a company got a large group of people and divided them up in groups. They took the largest group lets just say its 20 total people as the example for ease in that group and tailored an ad that is specific to them. They hit all the marks in the commercial based on predetermined likes and needs of that group. The group wanted a value, but it to look like a nice hotel. The group also travels for work, and breakfast included is a perk. They are ages 35-50 and the humor they like is somewhat goofy not edgy. All 20 watch the commercials and over 90% of them are impressed by Holiday Inn Express's promises. \n2 had previously bad experiences with the hotel, but are now reconsidering staying at another sometime to give them a chance. One in the group travels with a team in a company for promotions and is in charge of booking all the stays for everyone. Only one person doesn't think they would choose holiday inn express in the future. Most plan to use in the future if traveling. More than 10 plan to use it with in a year. Most importantly most will think of it now when the topic of getting a hotel room. Also people use company names as examples when suggesting things. Someones mother in law has to head in for a funeral. People part of the ad focus will now say stuff along the lines. Hey are you going to stay in town that weekend? Do you need to stay at the house or are you going to need a reservation at a holiday inn or something. The commercial plants that word to be less proper noun and just be a common noun for something. Like some people refer to soda as Coke even when it is not. Holiday Inn wants their name to be to the word hotel as Coke is to the word soda. Back at those 20 people though. Even only 20 people the possibility of those people being a driving force is endless. Not only does holiday Inn possibly gain their business the first time, but they have a chance for repeat business with those and all the referrals that come after that. \n\nNow multiply that by the number of people who watch any given prime time show live on tv, its in the millions. That commercial was designed for the largest group of potentially customers they could faction a commercial for. Of that group of hundreds of thousands of potential first time customers. They have to convince those thousands of customers to come in or come back so they can continue to form a larger and larger loyal customer base. \n\nAnd since their loyal customers die off eventually they have to continue this game until they are no longer profitable and viable as a company.\n\n\nIf an ad doesn't bring new customers in the door, the ad company is replaced.",
"Actually, advertising is all about hitting the right person at the right time. Obviously, ads fall on deaf ears when it comes to most of the people, but, as /u/oxencotten mentioned, it primes you as far as brand awareness is concerned and, the next time you actually need whatever it is they offer, you may look them up.\n\nAs for anecdotal evidence, while I usually am not swayed by commercials, a particular commercial drove me to a particular brand of trash bags, after they highlighted the issue of ruptured bags and made me realise I don't have to put up with that crap anymore, as a company was aware of the issue.",
"What I've read, and this may not be true, is that much of advertising is not able explicitly convincing you to choose one product over another(Holiday Inn vs Motel 6 for instance) but rather it very subtly influences you to choose one because we, as humans, generally choose the product we are most familiar with, given the utility it provides is roughly comparable with its competitors. If Holiday Inn blitzes you with ads, its possible that your increased familiarity with it compared to its competitors can almost imperceptibly influence you to choose it, if the service it provides is about equal in quality and price to competitors. "
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3r0smg | how and why do some substances stay in our body 'forever', like heavy metals? | I realise organic molecules eventually break down, but this isn't the case for heavy metals. Say we 'store' Mercury as an example, where does it go? Does it concentrate in one of our organs or something?
Why does the heavy metal not leave our bodies as we grow new cells and get rid of old ones? I remember reasons every single cell (minus some nerves etc) will be replaced within 7 years | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3r0smg/eli5_how_and_why_do_some_substances_stay_in_our/ | {
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"Every metal has what is called a biological half life. IF you up take it though ingestion, absorption or inhalation, it takes some amount of time to move through your system. \n\nThe concept is used quite a bit for body burden determinations when exposed to radioactive materials. The body does not differentiate between radioactive and not since they are chemically the same. \n\nSome things such as strontium, radium, plutonium, and samarium are \"bone seekers\". They are chemically similar to calcium and will be up taken by the body and end up in bone where calcium normally would be. It takes them a very LOOOOOONG time to leave the body once uptaken and deposited in bone. Plutonium has a biological half life of about 100 years. So if you uptake X amount of plutonium, in 100 years you would have 1/2 of X amount still in the body.\n\nNow Potassium-41 which is a radioactive metal and will be processed through the body fairly quickly since potassium processes quickly. Somewhere around 16-20 days. \n\nSo to answer your question: it depends on the specific metal. It is chemically similar to other metals used in the body, it will get processed like those. Depending on what it is similar to will determine how long it is in the body. Also what form it is in will determine quite a bit about how much is initially uptaken and how long it is retained. \n\n"
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6ikdu9 | Is there a tidal effect on our atmosphere? | So I understand that the sun and moon's gravity creates a tidal effect on the oceans of our planets, but do they cause a similar effect on our atmosphere? Or is it not dense enough? | askscience | https://www.reddit.com/r/askscience/comments/6ikdu9/is_there_a_tidal_effect_on_our_atmosphere/ | {
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"You are asking yourself a question that Newton and Laplace thought about several centuries ago and is still under [study](_URL_0_). Not everyone can say that. So: congratulations for looking at the world through a scientific mind!\n\nSure, there are atmospheric tides. There are solar tides although not in a gravitational sense, but a day-night radiative cycle. They play a very important role in atmospheric motions and mixing of air in the different layers of the atmosphere. For the moon tides, in the first place, keep in mind that when the oceans rise and sink, the atmosphere suffers the inevitable rising-sinking consequences too. However, there is an intrinsic gravitational atmospheric tide not coupled with the oceans. Lunar tides can be observed in the pressure pattern (once all other perturbations are eliminated) although they are very, very small (0.01% of the surface pressure). "
]
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cc4793 | how does _url_0_ work? i find it is very accurate; the thunder projection is almost always spot on, but i don't get how they can detect lightning. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cc4793/eli5_how_does_lightningmapsorg_work_i_find_it_is/ | {
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"There are lots of antennas that are registered with _URL_0_\n\nThose antennas detect lightning by means of picking up their electromagnetic waves they create when lightning occurs. If you get an AM radio, you can do the same by tuning it to the lowest frequency and listen for the static that happens when lightning strikes. Each of these antennas have their location known by GPS, so each antenna that detects a strike reports the strike and the system knows the gos location of each antenna and triangulates the strike and displays it on the map.",
"When lightening strikes, it makes radio waves, similarly to how objects make a \"whack\" noise when they collide. This radio \"whack\" is very obvious to any antennas nearby, and these antennas can compare the time at which they heard strikes in order to figure out where exactly the strikes are.",
"Thank you for asking this question. I had no idea this website existed. I have added it to my home screen. Thank you."
]
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1lohjn | why did the term milliard (now billion) seemingly vanish in the english language while it still exists in many other lanuages? | Or why did the affix '-ard' vanish in english counting? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1lohjn/eli5_why_did_the_term_milliard_now_billion/ | {
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"I was going to take a wild guess and say that in English, million and milliard are too close to each other phonetically, but that doesn't seem to be the right explanation.\n\n\nIt looks like in Europe billion originally meant a million million, until the French had the bright idea to change that to 1000 million, so 'milliard(e)' became superfluous. The US adopted this and stuck with it while France went back to the older system. [Source](_URL_0_) "
]
} | [] | [] | [
[
"http://www.etymonline.com/index.php?term=billion"
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3jn2gk | what is super symmetry and how does breaking it create new universes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jn2gk/eli5_what_is_super_symmetry_and_how_does_breaking/ | {
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"Supersymmetry is the idea that every particle has a heavier \"superpartner.\" Each particle come in two flavors, the lighter regular particle (like an electron) and the very heavy big brother (let's call it a selectron).\n\nThe electron is a fermion: it can't share states with other electrons. The selectron is a boson: it can share states with other selectrons. For particles whose regular version is a boson, like photons, their superpartner is a fermion.\n\nThe idea of the symmetry is that if you're out looking for particles, you will find an equal number of electrons and selectrons. They're symmetric, the universe is equally likely to produce either one, so you get a 50/50 split.\n\nWe've never observed a selectron in nature, though, so if this symmetry exists, it's broken. At very high energies, the symmetry may be true, but at low energy it's broken and we only see electrons.\n\nThere are a few reasons why we think that supersymmetry is true, despite never having seen a superpartner. The main one is that the Higgs boson doesn't have enough mass.\n\nThe interaction between the Higgs boson and the other types of particles should affect what its mass is, like how the interaction between an electron and the Higgs field gives the electron mass. The biggest mass correction to the Higgs is from the top quark, whose interaction should make the Higgs mass very large.\n\nIt's not very large, though, so something's wrong. What could be an explanation is that if there's another particle which interacts with the Higgs in the exact opposite way that the top quark does, the corrections neatly cancel out, and the Higgs has the correct mass. A stop squark (superpartner of the top quark) fits the requirements for such a particle.\n\nI am not aware of how supersymmetric symmetry breaking leads to new universes. They seem like unrelated ideas."
]
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||
2r2yn4 | why don't oreos absorb almond milk as fast as cow's milk? | So this is the first time I've consumed Oreos in a long while. I was dipping and dapping them in some almond milk and noticed they weren't acting the same. Thoughts, knowledge, ideas? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2r2yn4/eli5_why_dont_oreos_absorb_almond_milk_as_fast_as/ | {
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"text": [
"I don't want to be the bearer of bad news, but oreos have changed their recipe. They're using cheaper fats. They do not act the same in cow's milk, either."
]
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zhayn | How famous were Edwin and John Wilkes Booth before, say, the spring of 1865 or so? What celebrities today have a roughly similar level of fame? | I'm just curious if a similar level of reaction would be along the lines of, "Holy shit, Bill Murray's brother just shot the you-know-who!" | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/zhayn/how_famous_were_edwin_and_john_wilkes_booth/ | {
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"John Wilkes Booth would be more on the line of Johnny Depo.",
"Edwin was very famous. I'm currently looking through Brooklyn and NYC newspapers during the war years. Edwin was doing a run of shows in Brooklyn--they were HEAVILY reported. I think it's hard to compare them to current actors, but I would say compare them to sports teams. The way we follow and are \"aware\" of sports teams in our day-to-day lives is the same kind of thing.",
"I've always pictured them as the Wilson bros. Edwin was the more famous Owen, while John was Luke."
]
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70o5cf | why can't our mind just shut up? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/70o5cf/eli5_why_cant_our_mind_just_shut_up/ | {
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"Our mind's \"job\" is to keep us alive, so it uses its spare capacity to think about things that might harm us (and what to do about it), or opportunities to improve our situation.\n\nYou can learn to control it somewhat. See /r/mindfulness or (more advanced) /r/meditation."
]
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||
3mb9ep | Is it a coincidence that Reagan and Thatcher both came to power with similar ideologies at almost the same time? What brought on their surge in popularity? | I guess, more broadly, why did neoliberalism become popular when it did? And why in both the U.K. and U.S. Did it happen anywhere else?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3mb9ep/is_it_a_coincidence_that_reagan_and_thatcher_both/ | {
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" > Did it happen anywhere else?\n\nAt least I can answer this. In Sweden the Moderate Party was moving towards an [\"an increasingly Friedman-inspired and market liberal direction\"]( _URL_2_) but their \"Thatcherite era\" was [more in the 1990's.](_URL_1_) (Thatcher personally liked Bildt a lot.) \n\nThe immediate reason is listening to the economists like Martin Friedman, broadly the Chicago School.\n\nWhy exactly to them in why exactly in this era is more a complex econ question, although surely one big part of the reason is that the Keynesian school, that was largely the econ behind Social Democracy, had [difficulties with stagflation](_URL_0_).\n\nThis is only a part of the story. But very broadly, Social Democracy seemed to work really well 1945 -1975, France called this era the Thirty Glorious Years, and then there was all kinds of economic trouble and people were willing to listen to different ideas.",
"Douglas Rushkoff has argued that neoliberalism was a reaction to the basic income becoming a viable mainstream political idea in the '70s. (Proposals of this kind have taken various forms, but essentially basic income means a living allowance paid to every citizen.) Supporters said it solved the core dilemma of automation: new technology increases our supply of useful goods and services in the long run, but in the short run decreases demand for the same by putting people out of work. Theoretically, a properly-calibrated basic income would establish a floor under demand while the economy adapts. Once the likes of Richard Nixon and Milton Friedman had come out in favor, the Anglo-American right wing experienced an identity crisis and Reagan/Thatcher was the result.",
"I would say it's not a coincidence at all, and there would have to be a global cause which would likely be the OPEC oil embargo and subsequent economic shock on the Western countries it was leveled against. Prior to this, there was a relative consensus around Keynesian economic policies that had been formed in the aftermath of the Great Depression. Socially liberal governments dominated and built mixed economies based on strong unions, direct government intervention in major industries like healthcare, and high government spending to support growth. Adherents of Keynesian theory also relied on an underlying principal: that inflation and unemployment are inversely related. In other words, as long as there is high inflation, there will not be high unemployment.\n\nIn America, the existence of stagflation unraveled that consensus and the public began to look for a new theory to guide policy. I can only imagine the psychological effects of the world's most powerful nation suddenly finding itself having to ration gasoline based on license plate number and the President suggesting solutions like putting on a sweater to lower home heating. The US was almost entirely dependent on these imports, and the foundation of the entire economy was oil. When those imports stopped, the economy came to a grinding halt. \n\nBoth Reagan and Thatcher (and conservative figures in other nations I'm sure, but know less about) presented an alternative. Whether called trickle-down economics, Reaganism (\"voodoo economics\" by skeptics), or Thatcherism, it was bound by a rejection of Keynesian thought and the theory that lowering taxes (especially for the wealthy), deregulating markets, lowering government spending, and privatizing public markets would grow the economy. Both used public dissatisfaction with unions for their corruption and disruptive strikes (US airlines, UK coal) to initiate major union-busting campaigns that would lead to their demise. \n\nAs I mentioned, the oil embargo had profound psychological damage on the superiority complex of both the US and UK. Reagan and Thatcher each believed in massive military spending and used their tenures to restore American confidence. Reagan directly confronted a Soviet Union already in decline, and Thatcher used the Falklands controversy in what was largely considered to be an unnecessary conflict to reassert British dominance after decades of decolonization and losing its status as a global empire. \n\nI have to say that the 1960s Civil Rights Movement can't be overlooked in Reagan's election, but I can only speak on the US side of things. One of the most controversial aspects of Reagan has been his use of racial \"dogwhistling\" - using white working class fears concerning a recently liberated black population in order to win over a crucial electorate that had been loyal to the Democratic Party for its pro-immigrant, pro-labor policies dating back to FDR's New Deal Coalition. There's a lot that could be said here, but to keep this on topic, I think it still ties in with the overall ideology both he and Thatcher pushed: rebuilding a strong America/Britain that works for heavily-coded \"traditional\" public. ",
"Thomas Piketty also correlates the rise of Reagan/Thatcher to the surge of Japan and core European countries (mainly Germany) during this time. He thinks the countries that were catching up were bound to catch up since their economies were destroyed a lot more than the UK or the US during WW2. However, he says, the voters were scared and voted for the ideology championed by Reagan and Thatcher to get their countries' economies pulling ahead again.\n\nIn shorter words, other countries (esp. Japan) were catching up to the UK/US block mainly on their dynamic economies. The voters got scared. The right wing promised an alternative that voters thought could make US/UK pull ahead again.",
"This is based on Capital in the 21st Century by Thomas Piketty:\n\nAt the end of the second world war, the USA and the UK were in an excellent economic position compared to the rest of the world, because they suffered less destruction. This was especially true for the USA, who now had by far the biggest economy of the world(more than 50% of the world GDP, if I remember right).\n\nIn the next 30 years other countries(Germany, Italy, Japan, France etc.) all had their economic miracles, they were lagging behind but catching up fast. By around 1975 they had mostly caught up with the USA and the UK.\nThese countries now felt threatened, because they had been \"on top\" for the last 30 years and they thought that they had done something wrong and now things have to change.\n\nThis led to the election of Thatcher and Reagan, because they hoped they could overtake the rest of the world again, if they just became more economically liberal.\n\n",
"Previous answers touch on most of the obvious economical factors that led to a rise of neoliberalism in most industrialized countries in the 80's.\n\nAnother factor to consider is demography. That particular period of time (80-85) is also when the *majority* of Baby-Boomers (born between ~45-64) reached ~25-35 years old and had started families. That particular age group had virtual total control over any election because of their sheer number (in most industrialized countries, Baby-Boomers represented ~45% of the population by the early 60's). \n\nAlthough historically Baby Boomers had been more socially and economically Left-leaning compared to preceding generations, and had been highly favored with the post-War economic boom by their (relatively) easy entry and mobility in the growing job market; when the going got rough *twice* in the 70's (73-75 recessions, Energy Crisis, late 70's/early 80's recessions) the collective minding of Baby-Boomers began to shift. With young children and more on the way, many Baby Boomers became more conservative and Right-leaning fiscally, lending a good voting base for political parties that presented Neoliberalism as a solution to almost a decade (70's) of economical hardships. \n\nAnother factor to consider as well: the Cold War was still going strong in the 80's. So Neoliberalism was easily absorbed within already existing anti-Communist political platforms, the latter of which had a permanent voting base in the older demographics (those who were already adults in the 50's and 60's). So when some Baby Boomers voters migrated to more Right-leaning fiscal ideologies, Conservative/Neoliberal candidates had an easy -- if not overwhelming -- upper-hand.",
"As a professional historian of the 20th-century USA, I must say this has been a really strong thread. Thank you all!\n\nI would add a couple points from a transnational perspective. When neoliberal policies became dominant throughout the Western world, both in liberal and social democratic countries, was in the aftermath of decolonization. Keynesian thinking was popular with imperialists who needed not to worry about stagflation because the unequal trade relations they could count on with their colonies or their neighbors' colonies kept core economies growing. Once colonies began breaking away and nominally independent states like Chile began to behave like sovereign entities, Keynesian thinking grew incredibly dangerous. From OPEC to Allende, Third World polities began to turn statism against those who had benefited from this thinking for a century. Nationalizing copper, oil, or other natural resources and public amenities was in accord with Western behavior. The West forced what we now know as neoliberal policies on Chile with the Pinochet coup. That country became the laboratory for figuring out whether social collapse would follow. As much as I hate what happened there, Pinochet's Chile worked, and Carter/Reagan and Thatcher promptly followed suit. Why did neoliberalism take off c. 1980? Because it was already in place in Latin America's cone and had proved workable.",
"People focus on the effect of Reagan and Thatcher in the 1980s on the revival of free market capitalism. But most everybody – including in this thread – miss the leader of greatest importance for the free market's resurgence: Deng Xiaoping. Beginning slowly in 1978, Deng made changes that opened China to market systems and foreign investment, and not just in a *de facto* manner, but explicitly justified as adopting market techniques from capitalists, saying on one occasion: \"We mustn't fear to adopt the advanced management methods applied in capitalist countries…\" In the long run, the reform path begun by Deng Xiaoping and continued by his successors may be viewed as more consequential for global capitalism than anything done by Reagan or Thatcher.",
"Im new but actually wrote about Reagans popularity in my bachelor's paper in history.\nAs a background Reagan thought of himself as one of the people, \"we against them\" mentality. A mentality which he kept going on to the oval office.\n\nBut what made him a neoliberalist was according to David Stockman in his book \"the triumph of politics\" was that Stockman backed Jack Kemp as the republican presidential candidate. Jack Kemp together with his group was influenced by Milton Friedman and Fredrick Hayek saw a free market , lassiez faire market. Jack Kemp agreed to drop his candidacy if Reagan back his economical plan. Stockman jumped camp and became extremely important in creating what would become Reaganomics.\n\nThe problem they saw under the Carter precidency with a stagnation inflation market, later dubbed stagflated market, made it easier for Jack Kemp and his group to promote a neolibralist economy.\nReagan believed in Neolibralism because according to himself he would in his actor days make a certain number of films to escape paying taxes. A system which cut down on taxes and governmental interference would create a market that would regulate and would be self reliant. With a higher income in the richest percentages in the population together spending cuts in government would cut down on governmental debt. The money would simply trickle down from the top and benefit everyone.\nAnother seperate argument is that the democrats had a philosophy with governmental interference from FDR via JFK. It is argued that the republicans did not have a similar inheritance which made the small government -trickledown- solution easier to like, even though it was doubbed voodoo economics by Bush Sr. In the republican candidate debates.\n\nFinally it was much easier to accept because of the failiures of Jimmy Carter to stop the stagflation and his controversy with the Shah of Iran.\nSo sorry for the lack of structure guys and the nd language. Have a nice evening",
"Canadian follow-up: Brian Mulroney came to power around the same time. Was it for the same reasons discussed above?"
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"https://en.wikipedia.org/wiki/Stagflation#Explaining_the_1970s_stagflation",
"https://en.wikipedia.org/wiki/History_of_Sweden_\\(1991%E2%80%93present\\)#The_Bildt_Era",
"https://en.wikipedia.org/wiki/History_of_Sweden_\\(1967%E2%80%9391\\)#Right-wing_intermission"
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9w3vm8 | when a whale dives to depths of thousands of feet, why does the extreme pressure not force seawater through its anus into its colon? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9w3vm8/eli5_when_a_whale_dives_to_depths_of_thousands_of/ | {
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"By having colon muscles strong enough to prevent that.\n\nAlso they have eyes, mouths, blowholes... why would you single out their anus?",
"Cause mr whale sqeezes his bum hole shut, just like you do at the pool when you do a big jump.. bodies can do amazing things even without us having to pay attention ! "
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5exk0a | why are neo-nazis even a thing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5exk0a/eli5_why_are_neonazis_even_a_thing/ | {
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"The logic is fear. Neo-nazis see themselves as surrounded by other people that have things they don't. So, they subscribe to a philosophy that allows them to tear those people down and negate their achievements. Thus, they are able to feel better about themselves because their entire belief system places them at the top of the food chain.",
"Racial superiority is a concept that never died after WW2, it has always existed. The national socialist party had put so much research and effort into the study of racial superiority and the concepts of unter Menschen and codified it into culture that it made it easy for other groups to adopt. \n\n"
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pwffd | Is a superfluid a Bose-Einstein condensate ? | In most sources that I've seen treat Superfluidity at a very introductory level, Bose-Einstein condensates are invoked to explain it (for example in most Statistical Mechanics books such as Huang, Pathria, etc.). However I have recently come across some physicist stating that this approach is fundamentally wrong since in a superfluid state only a small fraction of the system is in a BEC and it doesn't account for the superfluid characteristics (see for example [this](_URL_0_)).
So I have been left wondering, does superfluidity have anything to do with Bose-Einstein condensates ? If not, what are the differences and why are they usually compared ? Thanks.
Edit: To clarify. I know the arxiv paper I linked states that the difference between the two is that Superfluidity emerges in systems with interacting particles while BEC is a property of ideal boson gases, and in fact this difference is mentioned (albeit not in much detail) in the books I named before. What I do not understand is, if there is such a difference then why are they usually compared ?
P.D.: I have resubmitted the question under permission of a moderator since the initial one got caught in the spam filter and I didn't realize until several hours later. | askscience | http://www.reddit.com/r/askscience/comments/pwffd/is_a_superfluid_a_boseeinstein_condensate/ | {
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"It's uncertain at this time. They share a lot of properties.",
"I work with atomic BECs on a daily basis and atomic physicists tend to put a very blurry line between superfluids and BECs\n\nTo have a superfluid, you typically need interactions between particles that causes *collective* excitations. i.e. An excitation in a superfluid with a momentum **k** is not actually just a single particle but a density wave in the superfluid whose energy is given be E = c|**k**|, where c is the speed of sound in the superfluid. \n\nIn contrast, the excitation of a *non-interacting* BEC really is just a single particle with energy E=**k**^2 /2m. Now typically when you make a BEC, you use interacting particles and when they're trapped at a low enough temperature, their density becomes high enough to start displaying superfluid behaviour. You could still have a very dilute BEC that displays a very tiny superfluid fraction or a very dense BEC that displays a larger superfluid fraction. \n\nA BEC only means that the ground state of your boson system is macroscopically populated, where as a superfluid has the constraint that excitations be collective rather than single particle.\n\nHope that answered your question.\n\n*Edit*: Just as you can make a BEC without making a superfluid, you can make a superfluid without making a BEC. This is a somewhat newer concept, but the idea is that instead of condensing single bosons into the zero momentum ground state, you condense *pairs* of fermions (which act as bosons because of the sum of their spins) in the zero *center-of-mass momentum* state. In this way, the zero momentum state is not occupied, but if interactions are large enough you can still have something called a BCS superfluid. Now if you turn up interactions even more, you can actually make a BEC of molecules."
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2l3oxj | When a large nucleus absorbs a neutron, why does it undergo fission and not just emit the neutron? | For example:
U-235 + neutron → U-236 → Ba-141 + Kr-92 + 3 neutrons + energy
Why not just emit the neutron and return to the original nucleus:
U-235 + neutron → U-236 → U-235 + neutron
Sorry if the original question is badly worded, hopefully this makes more sense. | askscience | http://www.reddit.com/r/askscience/comments/2l3oxj/when_a_large_nucleus_absorbs_a_neutron_why_does/ | {
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"In a nucleus, it's a competition between the nuclear strong force and electromagnetic repulsion to hold the nucleus together or split it apart.\n\nIn a large nucleus like U-235, the nuclear strong force *barely* edges over the electromagnetic repulsion. You have to note that the nuclear strong force falls off rapidly with distance and is negligible beyond a certain range.\n\nFor the nucleus to absorb the neutron, the neutron has to have significant kinetic energy when colliding with it. When the neutron gets absorbed, the momentum deforms the U-236 nucleus and \"stretches\" it. \n\nIf your neutron is travelling fast enough, this stretching can bring parts of the nucleus beyond the range of the nuclear force, and the electromagnetic repulsion forces the nucleus apart.",
"/u/I_Cant_Logoff gave a very nice answer. I'd only add that what you describe can happen. For example, the inelastic cross section for a 1 MeV neutron incident on a U^235 nucleus is about 1.8 barns, about half the elastic scattering cross section and about 1.5x the fission cross section.\n\n"
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2qa6oy | how come computer hardware is getting better and better, but at the same power cost? | It just seems odd and amazing (yeah, both at the *same* time) how it just got better without any losses. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qa6oy/eli5how_come_computer_hardware_is_getting_better/ | {
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"It's not always about the NUMBER of circuits they can fit onto a board, but also about the efficiency of those circuits, and building a physical electrical layout that will provide better computational processes.\n\nThink about the switch from HDD to SSDs - the increase in complexity and efficiency made a huge leap, but not because of an enhancement on the old, but a complete paradigm shift to a new architecture that had different power requirements than its predecessors.\n\nThat being said, in general, more complex hardware components have increased power requirements, though it's less than a linear progression for the reason above.\n\nBattery technology has also improved, allowing personal electronic devices to stay the same size while actually storing more power required to operate more complex systems."
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1zzypu | if we could farm lightning and did so, would there be any negative consequences? | Like, if lightning doesn't hit the ground but instead a big battery that powers the world would this cause the earth's electromagnetic activity to whack out. At a 5 right now | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1zzypu/eli5_if_we_could_farm_lightning_and_did_so_would/ | {
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"I dont think so... they're more or less seperate; ground and live are relatively isolated systems.\n\nSource: none, I'm basing this on nothing"
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2dhitx | Did Pagan religions have definite names? | Something that has long bothered me is calling pagan religions/traditions by their culture. Did religions like Nose, Germainc, Hellenic paganism have shortened names, or titles. I've seen Norse Paganism be referred to as Ásatrú. I'm not sure if that is a recent invention, but do historians have names for pagan religions beside calling them Blank Paganism? Or did the adherents to these faiths have titles for them? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2dhitx/did_pagan_religions_have_definite_names/ | {
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"Our modern conception of a religion as a distinct group that you belong to exclusively is something that has developed rather recently in the history of religious belief and actually coincides with the rise of Christianity and Islam in the West. In fact, in countries like China, such a distinction still doesn't readily exist. During \"Pagan times\", what we think of as \"religions\" were typically divided along cultural lines; certain cultural groups had certain deities, rituals, and beliefs about the world around them. However, there was not an idea that because you were Greek you could not worship Anubis or Odin because they were not part of \"your religion\", rather deities were commonly syncretized or traded when two cultures came into contact.\n\nThe closest thing to \"religions\" as we know them today were mystery cults, special religious groups with voluntary membership that provided spiritual fulfillment for those whose needs were not being met by the overarching state cults. These groups often purported to have secret knowledge that was only shared with initiates and promised direct experience with divinities in addition to benefits in the afterlife. These groups were rarely exclusive, however, and many people, such as the Emperor Julian the Apostate (the last Pagan emperor of Rome) were initiated into multiple mystery cults.\n\nThis changed when Christianity became popular during late antiquity. Christianity, unlike the mystery cults, specifically marked itself as in opposition to all other religions; they believed that there was only one God, only one way to worship Him, and that all other gods were lies or demons. Since they were an exclusive group, they were identified as one. Towards the end of the Pagan era, the Emperor Julian did try to reorganize the state religion of Rome into an organized religion along the lines of the Christian church and referred to this religious group as \"Hellenismos\" (\"those who worship in the style of the Hellenes\" in Greek).\n\nThis is something of a simplification and does not get into the continuing development of religion as an identity that occured once Islam rose in the Middle East and Christianity found itself faced with it's first organized opposition in centuries. If you are interested in the changes in the religious structure of the West during the fall of Paganism, I suggest checking out \"God Against the Gods\" by Jonathan Kirsch.",
"It's difficult to ascertain, but seems unlikely, as the forms of pagan worship that we have records did not keep a written word until after the introduction of Abrahamic monotheism, whose writers would have recorded as simply an equivalent for pagan, heathen or infidel. \n\nRecords of paganism would more describe the peoples who practised it, so a Scandinavian (Norse) who practised Pre-Christian beliefs was a norse pagan. It seems likely that the pagan followers would have simply refered to themselves as the peoples or region they came from, and they would practice the local beliefs and traditions. With the introduction of the new Abrahamic faiths, they might refer to themselves as something \"following the old ways\".\n\nNames such as Asatru (Norse), Romuva (Baltic), Suomenusko (Finnic) are the names given to the modern Neo-paganism movements, which usually claim some form of continuum from the pre-modern beliefs, rather than the historical forms. These names are created and used by neo-pagan followers, often which may translate to something like \"The Way\".\n\nDavies, Owen (2011). Paganism: A Very Short Introduction. New York: Oxford University Press. ISBN 9780191620010.\n\nRobert, P. & Scott, N., (1995) \"A History of Pagan Europe\". New York, Barnes & Noble Books, ISBN 0-7607-1210-7.\n\nBlain, Jenny; Ezzy, Douglas; Harvey, Graham (2004). Researching Paganisms. Oxford and Lanham: AltaMira Press. ISBN 978-0-7591-0522-5\n\nLewis, James R. (2004). The Oxford Handbook of New Religious Movements. London and New York: Oxford University Press. ISBN 0-19-514986-6",
"Groups/tribes/peoples all over the world had names for themselves, but often in small scale societies the names for themselves just translate as \"the people\", \"the real people,\" \"the free people,\" \"the original people\", \"the brave people\", etc. Take the Germans, for example. Our word is untraceable past the name of the Germani, a specific tribe. But in German, they're called *Deutsch*, which is related to a Proto Indo European root meaning [people](_URL_4_). The Germans in French are les allemands, which is ultimately likely related to \"[all men](_URL_0_)\". French, for example, comes from the Franks, who were the [free [not servile] ones](_URL_2_). Swede originally either meant [free or kinsmen](_URL_5_). The Navajo word for Navajo is Diné, meaning the People. The Cree either call themselves \"Nēhilawē, those who speak our language, or Eeyou, the people. The Guaraní called themselves Abá, meaning men/people. This pattern is repeated throughout the world, though obviously it doesn't apply to every single group of people. Other names might be like \"those who live by the rapids/in the forest/on the plains/to the north\" or \"those who eat [the thing their neighbors don't eat]/do [what our neighbors don't do]\", etc.\n\nJust as \"who we are\" is distinguished from \"who they are\", \"what we do\" is often distinguished from \"what they do\". The term religion, and particularly in its current meaning, is surprisingly recent, only coming out of the nearly simultaneous events of the European discovery of the Americans and the schism between Catholicism and Protestantism (see J. Z. Smith's \"[Religion, Religions, Religious](_URL_3_)\"). But even though the term is new, what we'd call religion existed much longer. But they were probably differentiated similarly to people, our religion was \"the way of gods\" or \"our path\" or \"the true law\" or \"the original custom\" or \"knowledge of the spirits\" or something like that. One of the problems is that for most groups, writing and contact with one of the great proselytizing religions (Buddhism, Christianity, Islam) is almost simultaneous, so a lot of the records we get are through non native eyes. I can't remember how the Sumerians and Egyptians talked about their religions, but the Dao Te Jing, a fundamental text in Chinese religion (especially Daoism, of course), says famously, \"The way that is spoken is not the way. The name that can be named is not the constant name.\" But, here \"way\" is literally \"dao\", so another way to translate this line is \"The Tao that can be told is not the eternal Tao.\" The word \"veda\", used in Hindusim, means \"knowledge\". \"Torah\" means \"Law\". Dat, the Modern Hebrew for religion, originally meant [\"law\" or \"custom\"](_URL_1_). And so on.\n\nSince I know some groups, even some small scale societies, have more specific names for themselves than \"the people\" or \"the free ones\", I can feel confident that some groups had more specific names for their religions than \"our customs\" or \"the true way\", but I can't think of any off the top of my head."
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"http://www.iupui.edu/~womrel/Rel433%20Readings/SearchableTextFiles/Smith_ReligionReligionsReligious.pdf",
"http://www.etymonline.com/index.php?term=Dutch&allowed_in_frame=0",
"http://www.etymonline.com/index.php?term=Swede&allowed_in_frame=0"
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1wefiv | Why is e an irrational number if it is the sum of rational numbers? | I know the formula for calculating e is the sum of (1/n!) where n starts at 0 and goes in to infinity. But all those numbers are rational. So how is e itself irrational? | askscience | http://www.reddit.com/r/askscience/comments/1wefiv/why_is_e_an_irrational_number_if_it_is_the_sum_of/ | {
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"The property that sums of rational numbers are rational only holds for finite sums. As a matter of fact every irrational number can be expressed as an infinite sum of rational numbers, that sum being it's decimal expansion. Namely an irrational number (between 0 and 1 for simplicity) can be written out as 0.a_1 a_2 ... a_n ... which can also be expressed as the infinite sum of a_k 10^-k , where k goes from 1 to infinity.",
"Every irrational number is an infinite sum of rational numbers. Pi is 3.14159... = 3 + 0.1 + 0.04 + 0.0005 + 0.00009 + ....\n\nInfinite \"sums\" aren't the same as finite sums. Finite sums are binary operations; that is, they are defined for pairs of elements: the element on the left of the + sign, and the one on the right. However, addition is associative, meaning that (a+b)+c is equal to a+(b+c), and by extension we may conclude that parentheses are redundant and write both of the above expressions as a+b+c. We can extend this to any *finite* number of terms that we like, which thankfully saves us from having to write a+(b+(c+(d+e))). But addition of finitely many terms *can* be written as a sum of *two* terms once the appropriate number of parentheses has been peppered in, and we know that if p/q and r/s are rational numbers then p/q + r/s = (ps+qr)/qs which is rational. This proves that any *finite* sum of rational numbers is rational.\n\nHere is the important thing: finite sums and infinite sums, although they have similarities and suggestive-looking notation, are very very differently defined. In particular, the definition of a finite sum typically makes no reference to limits. However, the definition of an infinite sum is exactly a limit: it is the limit of the sequence of partial sums. So e for instance is *the limit* of the sequence \n\ne=lim{1, 1+1, 1+1+1/2+1/6, 1+1+1/2+1/6+1/24, ...}\n\nIn fact, you could say that the whole reason that irrational numbers exist is to fill the *holes* that are generated by these sequences. See, you know that the above sequence converges in the real numbers; indeed it converges to e. You also know that e is irrational. That means that the above sequence *does not* converge in the rational numbers. If you think about it though, this is strange behaviour in a world where we only have rational numbers. In decimals, the sequence looks like {1, 2, 2.5, 2.67, 2.71, 2.72, ...}. That sure *looks* convergent; the terms are getting closer and closer and closer together. But in the rational numbers, this sequence does not converge to anything. It also doesn't diverge to infinity. It just keeps getting closer and closer to.... *something*. That *something* is exactly how we define the irrational number *e*, as the limit of a [Cauchy sequence](_URL_0_) of rational numbers. Every real number is the limit of a [Cauchy sequence](_URL_0_) of rational numbers, essentially by definition, so e is not special here.\n\nI typed that out in a hurry so let me know if anything wasn't clear :) I feel like it is riddled with errors.",
"Infinite sums aren't the same as sums. The sum of two rational numbers is again rational, but the infinite sum of rational numbers isn't even unambiguously defined, let alone rational. Given the standard way infinite sums are defined, *every* irrational number is an infinite sum of rationals (since the irrationals are defined as limits of sequences of rationals, and infinite sums are most often defined as limits of sequences of partial sums). \n\nFor a fairly in-depth explanation of infinite sums, [check out this previous post of mine](_URL_0_).\n\n"
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3h4dcm | why aren't time zone borders straight and equidistant from each other like longitude/latitude lines? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3h4dcm/eli5_why_arent_time_zone_borders_straight_and/ | {
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"Because all countries can choose what time zone they observe.\n\nThat's why all of China observes the same time zone officially.",
"Time zone borders are roughly drawn 15 degrees apart, but move do to the convenience of commerce.\n\nIt would be really bad, for example, for a time zone boundary to cross in the middle of a city. It would help nothing, and cause a lot of problems.\n\nSo, whereever possible, the time zone boundaries are in rural areas where the economic impact of the time change is minimal.",
"Time zones are for the convenience of people, not a reflection of some absolute truth.\n\nThey generally line up with borders of nations & states. Inside a country, a small town might be put into the same time zone as a major city it's close to, even if the \"natural\" TZ border would have it on the other.",
"Longitude/latitude are precise measurements used for location. Time zones are a pretty modern invention to standardize times for business and transportation, and generally run along political borders.",
"A lot of people like a sort of perpetual daylight savings times. So a lot of the borders are farther west than they are naturally. ",
"Time zones became a thing in the US after railway travel became fast enough that it started to matter if \"noon\" in one town was a couple minutes different from \"noon\" in a town 20 miles away. When the time zones were standardized they were set up in such a way that the major railway companies would have all of their lines in the same time zones. These passenger railway companies are basically all gone now but their legacy lives on in the weird seemingly arbitrary way that our time zones are laid out.",
"Because countries are not straight and equidistant from each other. Even in the US, time zones mostly go around state borders so states can remain entirely in one time zone. "
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1dcqod | What do we know historically about the events of the Book of Exodus? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1dcqod/what_do_we_know_historically_about_the_events_of/ | {
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"This book:\n\n_URL_0_\n\nwould seem to indicate that there's basically no historical basis behind Exodus and the book seems to have been favorably reviewed by both Biblical Scholars and archeologists.\n\n",
"There is no physical evidence of the Israelites bondage in Egypt nor their 40 years of wandering through the desert. If the biblical numbers are to be believed then a group of 600,000 people wandering the desert would certainly leave some physical trace like pottery or waste or mass graves. When you compare the traces of other cultures left behind, it is rather curious there wouldn't be any traces. So really, we don't know anything about the historical exodus. are best evidence is the religious texts themselves. \n\nOn the other hand - the Israelites don't come into the physical historical record until the time the bible claims they have reached and conquered the land of Israel. Other, later biblical stories like Nebakanezer conquering Jerusalem do have historical veracity. So it is possible they may have happened, and we just haven't found the evidence yet. ",
"You may be interested in these previous questions about “[Is the Bible historical?](_URL_1_)” and “[Did the Egyptians use Jewish slaves to help build the pyramid?](_URL_0_)” on our **Popular Questions** page (which is linked at the top of every page in this subreddit, and in the sidebar).",
"It seems unlikely to find evidence more than three thousand years after a nomadic people’s wandering in the desert, even if it did last forty years. After all, they built no permanent structures. However, there is evidence that the Hebrew language was well known in ancient Egypt, which is consistent with the biblical claim that the Hebrews were enslaved in Egypt for a long period of time. In 1887, about 350 clay tablets were found at Amarna, the modern site of the ancient Egyptian capital of Akhetaten. The tablets are written in the Babylonian language using cuneiform characters. Most of the letters are dated to the reigns of Amenhotep III (also known as Amenophis, 1386-1350 BC) and Amenhotep IV (Akhenaten, 1350-1334 BC). They contain correspondence describing the state of international affairs between Egypt and the major powers in Babylon, Assyria, Syria, and Palestine. The Amarna letters contain evidence that the Hebrews were at one time a significant presence in Egypt. Old Testament scholar Robert Dick Wilson explains, “The fact that there are more than one hundred explanations in Hebrew of Babylonian words in the Amarna letters shows that Hebrew was understood at the court of the Egyptian kings, Amenophis III and IV. This confirms the biblical account of the residence of Israelites in Egypt before the time of Moses.”\n\nThere's also evidence that the Hebrews displaced the Canaanites in present-day Israel. Primarily, the very presence and growth of the nation of Israel in Palestine is evidence of them conquering the Canaanites who inhabited the land before them. However, there also is some archaeological evidence of Israel in the land of Canaan around the time of the Exodus: \nSome of the Amarna Letters refer to Israel attacking the Canaanites.\nA collapsed double city wall and a residential area have been discovered at the Jericho excavation site (1400 BC).\nThe Merneptah Stele is a granite inscription by an ancient Egyptian king (1213 to 1203 BC) which mentions Israel and Canaan.\nThe lack of evidence for any particular biblical story should not automatically cause us to doubt the veracity of the account considering the enormous number of ways archaeology has already corroborated the Bible. Scripture has certainly earned the benefit of the doubt many times over. In the case of the Exodus, the very nature of it suggests that physical evidence would be lacking, but we have corroboration at around the right historical time that Israel was at one time in Egypt in great numbers and then later they were in Canaan in great numbers. The Exodus makes perfect sense of how that happened. Check out these books:\n \n1. On the Reliability of the Old Testament by K.A. Kitchen\n2. Archaeology & The Old Testament by Alfred J. Hoerth"
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1t54it | why do some cars make springing, popping noises when parked after a long drive? | I hope people know the noises I'm talking about. As a kid I always noticed it from my moms van, and now experience the same noises from my own past cars(the newest of which is from 2002, so it may be an older car thing.) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1t54it/eli5_why_do_some_cars_make_springing_popping/ | {
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"The noises come from the exhaust components and heat shield. As they cool off, they contract and create the noises. It happens to all cars, but some cars may create more of these noises than others."
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1php0t | if humans are multitasking capable, why is it not possible to count 2 different things in our head at the same time? (for example, heartbeat and seconds). | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1php0t/eli5_if_humans_are_multitasking_capable_why_is_it/ | {
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"We don't actually actively multitask. We shift our concentration from one idea/action to another. We can passively multitask however. Example: walking and chewing bubble gum."
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4d2ijz | In WWII, did Canada have a contingency plan to shelter the British monarchy if the UK was overrun? | I would assume they did, since they helped shelter part of the Dutch royal family, and the UK was far more important to Canada than the Netherlands, but I can find nothing outlining whether plans were in place for George VI and his family if Germany had overrun the UK, or what the plans would have been. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4d2ijz/in_wwii_did_canada_have_a_contingency_plan_to/ | {
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"I've never commented on this sub before though I'm a big fan. I don't have any flair and am not an expert or anything, BUT I happen to know the answer to this question and can document it. Please forgive me mods if I break any rules or need to change anything.\n\nIn a nutshell, the British did in fact make plans for the royal family to be evacuated to Canada in the event of an invasion, though there was some pushback from the Americans on making Canada the seat of the government-in-exile, as the Americans were uncomfortable with the prospect of a monarchy operating in North America.\n\nFrom Andrew Roberts' *The Storm of War*,\n\n > Although Britain's gold reserves were transferred to Canada, and plans were made for the royal family, the Cabinet and ultimately whatever was left of the Royal Navy to follow them, it was not even certain that the British Establishment would be universally welcomed by the North Americans. Ever loyal Canada was sound, of course, but on 27 May 1940 Churchill's private secretary, John 'Jock' Colville, noted in his diary that the British Ambassador to Washington, Lord Lothian, had telegraphed that afternoon to say that President Roosevelt had told him that 'provided the Navy remains intact, we could carry on the war from Canada; but he makes the curious suggestion that the seat of Government should be Bermuda and not Ottawa, as the American republics would dislike the idea of monarchy functioning on the American Continent!'\n\nSource:\n\nRoberts, Andrew. *The Storm of War* (2011)\n\nEdit: Addendum: If anybody is interested, the British also discussed the possibility of evacuating large numbers of troops to Canada as well.\n\n > It has been revealed that soon after Dunkirk Anthony Eden and the new Chief of the Imperial General Staff, Sir John Dill, convened a secret meeting in a hotel room in York which was attended by the senior officers of formations based in the north of England. The War Secretary asked whether the troops under their command 'could be counted on to continue to fight in all circumstances.' Brigadier Charles Hudson VC recalled that 'There was an almost audible gasp all around the table. To us it seemed incredible, almost an impertinence, that such a question should be asked of us.' Eden explained that in the circumstances the Government were envisaging, 'it would be definitely unwise to throw in, in a futile effort to save a hopeless situation, badly armed men against an enemy firmly lodged in England.' They would have fought on the beaches, it seems, but not so far north as York.\n\n > The subsidiary question that Eden and Dill put to the officers was 'Whether our troops would, if called on, embark at a northern port, say Liverpool, while it was still in our hands, in order to be withdrawn to, say, Canada? Without such a nucleus of trained troops from the Home Country, the Prime Minister's declared policy of carrying on the fight overseas would be infinitely more difficult.' Hudson related that it soon became very apparent that the officers were all of much the same opinion. While the proportion who would respond to the call among Regular officers would be high, and of Regular NCOs and men who were unmarried nearly as high, 'No one dared, however, to estimate any exact proportion amongst those officers and men who had only come forward for the war; a smaller proportion of unmarried men might respond but the very great majority of these would insist on either fighting it out in England, as they would want to do, or on taking their chances whatever the consequences might be.' The upper reaches of the British Army were therefore of the view that the majority of its troops would refuse to embark for Canada to continue the struggle from abroad, just as many French had not embarked for Britain for the same reason earlier that month. It was all the more vital, therefore, to prevent the Germans from landing in the first place.",
"As an extension, what would be the likely fate of the royal families if the Nazis captured them?",
"In addition to /u/apeman2500's well-written response, one should remember in relation to this question that during WW2, Newfoundland and Labrador were not part of Canada, but were directly governed by the UK.",
"To ask a follow up question:\n\nDid the British monarchy consider evacuating to Australia (or any other commonwealth countries)? Was Canada the only consideration, and if so, for what reasons? "
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1avwwv | So this is kind of a broad question, but in your opinion what has been the most peaceful society in human history? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1avwwv/so_this_is_kind_of_a_broad_question_but_in_your/ | {
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"On a macro scale: ours, modern Western society. (Source: Pinker's *Better Angels of our Nature*.) \n\nOn a micro scale: various pacifist cults and intentional communities (e.g. the Shakers) have dedicated themselves to complete non-violence, and would probably win.\n\nThis seems to me to be a [poll-type question](_URL_0_), though, and may not be allowed to remain."
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1k1d7y | Gravitational time dilation: what exactly slows? | So I've been reading about gravitational time dilation and my tiny brain is having trouble wrapping around the concept. Like what is it that slows? Obviously there's tests showing clocks slow down at different heights due to the gravitational differences but what is it that's making them slow down?
And if literally everything is slowly would a person experiencing a large time dilation even realise that it's happening? Because surely the neurons in the brain would slow down relatively to everything else meaning that everything to the person would still seem to be in a normal time frame. | askscience | http://www.reddit.com/r/askscience/comments/1k1d7y/gravitational_time_dilation_what_exactly_slows/ | {
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"Everything slows. Time ticks more slowly, not just particular clocks. You're right though that you would never notice this, your body and brain functions are slowed with time. From your point of view time passes as usual. But to an outside observer you're living life in slow motion.",
"Actually, _nothing _slows. You are by definition at rest with respect to your own frame of reference, so there is no time dilation to experience, regardless of brain function \"rate\". Effects like time dlation only affect what you observe, never you yourself. This is a very commonly misunderstood point in relativity."
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2iglnp | Could US soldiers come home temporarily from Vietnam war? | I've been wondering for a while, but nothing I've found online has a straight answer. Could American soliders in Vietnam come home at all for any reason, then go back to Vietnam?
I'm especially wondering about holidays- did any soldiers get to go back to America for holidays, and afterwards return to Vietnam?
Thanks! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2iglnp/could_us_soldiers_come_home_temporarily_from/ | {
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"No, they could not. Considering that a US soldier normally served for 12 months, they were given a one-week Rest and Recuperation leave after six months and were only permitted to visit either nearby destinations such as Thailand and Japan or destinations within South Vietnam itself. There was however one destination that was very popular with married soldiers and that was to spend that one week in Hawaii so that they could reunite with their wife and/or family. This was the closest they could get to where they came from and it was for this reason as to why single men also chose it as their destination over the otherwise more exotic choices that were available to them."
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17dkwx | acid vs. base? | One always thinks of acids as what burns. But I've learned that substances that are strong bases will do this too. Can someone ELI5 acid vs. base?
Bonus questions: would a neutral substance be equally good at counteracting both an acid burn and a base burn? Or would a strong base be best at counteracting a strong acid burn (and vice versa)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/17dkwx/eli5_acid_vs_base/ | {
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"This might get a little tricky to try to explain to a five year old, and I'm certainly no university level scientist, but I'll give it my best shot in layman's terms:\n\nAcids and bases are two groups of chemical substances. They have different 'chemical properties': this means that when you put something into an acid, like some types of metals, they will react and produce new substances, such as hydrogen gas, whereas if you put a metal into a base, that will not happen. Another example of the differences in chemical properties of acids and bases is the way they taste - acids taste sour (think of lemon juice, which is an acid) and bases taste bitter (baking soda).\n\nAcids and bases can be strong or weak, as you hint at in your question. A weak acid, like vinegar, can splash on your skin and it will do nothing. But if you throw a concentrated dose of strong acid, like the kind you'd find inside a car battery, on your skin then you're going to have problems. So, very generally speaking, if a substance corrodes (destroys) or irritates your skin, it doesn't mean that it's an acid as opposed to a base; it means that you're dealing with a strong acid or a strong base. \n\nNow, you're probably asking, what does 'strong' mean? Here is the point when a five year old could start getting a little confused. First, we need to talk about water. Water, like every other substance that takes up space, is made up of particles called atoms, bonded together by special forces of attraction. The atoms are bonded together in groups called molecules. The molecules that make up water contain one atom of oxygen and two atoms of hydrogen - you've heard of H20, right? The molecules of H20 in water want to stay together because they're happy like that. The hydrogen and oxygen have a 'sharing is caring' kind of relationship with each other. If they didn't, then the water would no longer be water, but I digress - back to acids:\n\nAcids are substances made up of molecules too. Acids molecules all have hydrogen in them, just like water. Think of hydrogen as an important building block for both substances. Something interesting happens when you pour molecules of acid into water. Some of the molecules of acids kind of ... break up as they're floating around in the water. The hydrogen in some of the acid molecules goes and hangs out with some of the water molecules. Now, I'm grossly simplifying here, but water molecules as you remember are made up of hydrogen *and* oxygen; and oxygen is very good at attracting hydrogen. \n\nWhat happens in those acid molecules that do split up is that the hydrogen leaves the acid molecule because it's more attracted by the enticing oxygen in the water. What happens then? Well, instead of having H20, what you have now is essentially a H30 molecule. (We call this hydronium) Now, how many molecules of the acid split up and make hydronium depends on the acid. **A weak acid** will have few molecules that split up and not make much H30 in the water. **A strong acid** will make *lots* of H30. You should know at this stage that even pure water will make some H30 just by itself. It does this when hydrogen from the molecules of water are more attracted by the oxygen of another molecule of water nearby. Think of this as someone in a threesome ditching its partners to to make a foursome. This is why you may hear people say that water has acid like properties. This is because essentially an acid -- in a very general and oversimplified way -- is something that makes some molecules of water (H20) become molecules of hydronium (H30).\n\nOn the other hand, a base is a substance that will lower the number of hydronium (H30) molecules in water. This is because molecules of a base contain usually in their molecules, oxygen and hydrogen grouped together (OH^-). When you put a base in water, the oxygen and hydrogen in the base molecule say to the other atoms in the molecule 'see ya, losers!' and go looking for H30. If you're clever, you'll realize that the OH^- is going to pull away those extra little Hydrogens from H30 to make good old neutral H20. If you keep putting a base in water, you'll have more and more OH^- groups floating around in the water. A stronger base is not one with more OH^- in the water, but the one that will more readily pluck away the extra hydrogen from the H30 molecules.\n\nSo, how do we conclude this lesson? If you stick your hand in a beaker of acid dissolved in water, the strong acid is going to have created a lot of H30 molecules in that beaker. Unfortunately for you, the H30 molecules really like to play and make friends with the long Hydrogen-carbon molecules that make up your skin. You'll have a lot of jumping around of atoms as the H30 tugs away and rearranges the atoms that make up your hand. This is going to feel like it's burning your hand, but essentially what's happening is that the molecules of your skin are breaking down in the acid, making new molecules, and generally ruining your day. \n\nNow if you have a strong base, you'll know that it's a substance that's going to be very good at plucking hydrogens away. Hydrogen from the cells that make up your hand (and remember there's also a lot of water in you) are going to just love playing with all those OH^- groups, and a similar effect happens. Chemical reactions, sizzling, pain, bad times.\n\nTo address your bonus question using the snippet of what we've learned:\n\nWhen we think of a neutral substance, we need to think of pure H20. When you *neutralize * an acid or a base, what you're doing is trying to is get back to that pure H20 that will not react with the same things acids and bases do. \n\nNow think about this: if you poured pure H20 on acid molecules, is it going to turn the happy little H30 molecules back into H20? Nope! It's just going to **dilute** the acid. The nasty little H30 are still there and happy to burn your little paws off, mind you; they're just swimming amongst more H20 molecules.\n\nSo what do you need to do to make those H30 into pure, neutral H20? You're going to need something that plucks away those extra hydrogens. So, homework question is, what substances can do that for us? ",
"All acid molecules have a hydrogen molecule (H) that is susceptible to separating from the rest of the molecule. All bases have a hydroxide part (OH) that is susceptible to separation when they interact with something else. \n\nSo, hydrochloric acid (HCl) will split into a hydrogen atom (H) and a chlorine atom (Cl) when it gets mixed with, say water. \n\nA base on the other hand, like sodium hydroxide (NaOH - commonly known as Drano) would split into OH and Na when mixed with water. \n\nThere are a lot of properties that follow from this, but chemically speaking this is the difference. The reason water is neutral (H2O) is because it splits into H and OH, effectively exhibiting the requirements for both an acid and a base."
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3zq79k | What do we actually know about human sacrifice among the ancient Maya? | On a trip to Mexico, I was told by two different tour guides at Mayan ruin sites that the Western world greatly misunderstands Mayan human sacrifice. One guide denied any evidence of human sacrifice among the ancient Mayans, explaining the artistic depictions as symbolic. The other guide acknowledged that it may have happened, but added that it would have been considered an honor for one to give their life in such a manner. For example, he claimed that the *winner* of the notorious ball game, not the loser, would have likely been the sacrificial victim.
From the perspective of a non-historian, this is confusing. Given how little we know about the ancient Maya, I wonder if anyone here can shed some light on objective evidence we have for Mayan human sacrifice? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3zq79k/what_do_we_actually_know_about_human_sacrifice/ | {
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" > Given how little we know about the ancient Maya\n\nAaah, but we know so much. In fact, the Maya may be one of the most well understood cultures of Mesoamerica with the Aztec at a very close second (sorry /u/400-rabbits). I put the Aztec second because we have to rely on post-Contact produced documents to get insight into Aztec culture. The Maya, however, had their own writing and offered insight into their world using their own words which offers you a fantastic emic rather than etic perspective.\n\nAs for what we know about human sacrifice, we know a lot. We know that people were actually sacrificed in a variety of manners and methods befitting a particular ceremony or dedication to a particular god. Human remains have been recovered from archaeological contexts which indicate that the person was killed by another person. And the context of the remains and the kinds of goods the person was buried with further illustrate that it was a sacrifice rather than the internment of an injured person. The ballgame sacrifice is a little bit contentious. There is a lot of imagery related to sacrifice and the ballgame, but nothing explicit. The imagery ties in heavily with the Hero Twin myth and is more of an allusion to the story rather than an actual practice.\n\nSince the topic of sacrifice is so broad and has been debated for so long, I do recommend actually picking up a book and reading about it since the book will do a much better job of explaining sacrifice in the Maya world. There is a fairly new book out which focuses specifically on the topic of Maya sacrifice along with ritual body treatments.\n\n* Tiesler, Vera, and Andrea Cucina, eds. New perspectives on human sacrifice and ritual body treatments in ancient Maya society. Springer Science & Business Media, 2007."
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2m3n6n | why is it so common to dream you are flying? | A common theme in dreams is to be able to fly, or at least hover at a small altitude. What causes it and why is it so common?
All the explanations I found have to do with desire for freedom or such, but I'd like to see other answers if possible. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2m3n6n/eli5_why_is_it_so_common_to_dream_you_are_flying/ | {
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"I want to know why I have never had such a dream, but it seems everyone else has. ",
"Its probably to do with your mind interpreting the feeling of weightlessness during sleep. Similar to how your body feels like it drops into the bed when you jolt awake? Just a guess though :)",
"Sub-consciously, you brain replays past events throughout your sleep. The feeling of flying is closely related to being on a roller coaster, with the feeling of your stomach dropping, like in an elevator.",
"these explanations trying to tie in physiological causation aren't doing it for me. when i dream about flying there's always a positive emotion along with it, usually being astounded and then elation. and they are always really realistic feeling. i'm with op, i think there's some innate desire.",
"I keep on hearing about flying dreams that everyone has. I've never had a dream like that. The closest drew I had to that was a dream in which I could power jump...",
"I can come up with three reasons to why you want to fly when dreaming. \n**1.**It might be because you want to see the world in another point of view.\n**2.**If you feel like the flying is uncomfortable, maybe you want to get away due to poor self-esteem or other noteworthy reasons. \n**3.**If you like the feeling of flying and it is percieved as something good, you might yearn for simply something more fortunate in your waking life. (Like sex).\n\nIt is all psychological so I have no clue on why people dream about flying so commonly, but hey, it might be one of these reasons. \n\n-Wagenknecht\n"
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8why1t | why is virginity something you “lose”, or else “take” from someone else? where did this idea originate? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8why1t/eli5_why_is_virginity_something_you_lose_or_else/ | {
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"I don't know the orgin, but I always thought about it as innocence. Like virginity and innocence are almost interchangeable. \n\n\"He took her innocennce\" \n\"He lost his innocence to the family dog\"",
"Isn't it because it was literally taken from girls, whether through arranged marriage, rape and pillage etc.? What I'm getting at is that back in the day girls rarely had a choice in who 'took' it. ",
"These conceptualizations of virginity come to us from a history of European land ownership succession. In Europe, land was passed down father to firstborn son. With no DNA testing, the only way to \"ensure\" that your wife would give birth to your child and not someone else's was to make sure you were the first and only man she ever had. Considering women were literally regarded as property during this time, their worth was mostly determined by their ability to produce heirs you could trust to be yours. Add in a healthy dose of religious sexual repression and incurable STD's, and you've got yourself a great recipe for oppressing half of an entire species.",
"Because historically female virginity was something quite valuable and losing it or having it taken from you was a major thing with all sorts of implication beyond just sex.\n\nPeople put a lot of worth into virginity because the physical aspect of it was something that could be actually verified. It being the first time you had sex with your husband was something that could be noticed and if you kept the bloody sheets the couple could even prove it to others.\n\nThis was important because paternity was important, because family was important.\n\nBeing a virgin on your wedding night was seen as a pretty good indicator that any child born 9 month or a bit less down the road would be the husbands. That is important for questions of inheritance.\n\nOf course nowadays paternity and faithfulness are important too, but in those days there was no way to test paternity with DNA or even by comparing blood groups. Also in those days there was no real social welfare net. No unemployment benefits or anything like that you either had a family take care of you when you couldn't take care of yourself or you were mostly fucked.\n\nFamily was important because without the modern state taking care of people it was all they had.\n\nA girl's virginity was a bargaining chip that could be exchanged for a lifetime of benefits. It was worth quite a lot and carelessly giving it away or having it cruelly taken from you is a catastrophe that could destroy a lot.\n\nIt is why rape was seen as such a big crime in many cultures. Not because of the suffering of the woman, but because of the damage done to her family, especially her father if she was a virgin.\n\nIt is why in old stories women who have done the deed will talk about being ruined or no longer being fit for marriage. Or why even today people talk about \"taking responsibility\".\n\nIt is the general idea of \"you broke it - you bought it\". No one would want a bride who was not a virgin and thus the one who caused her to loose her virginity was expected to take care of her. It is why you get parts in the bible (and in older religious influenced law books), that have marriage as an out for rape or sex with a minor.\n\nEven worse in societies were there is no strong central authority to keep the peace people and families survived based on their reputation. Reputation or honour was a life or death thing in many societies. A girl who got a reputation for having lost her virginity, would not just reflect badly on her, but also on her family. Which is why extreme measure were often taken to avoid harm to ones honour and repair ones reputation. It is how you get honour killings.\n\nSo virginity was a matter of life and death in some cultures (and evens still is in some today) and even if you weren't in danger of being killed by your own family over losing it, you might still get cast out or at miss out on finding a good husband who (together with his family) would provide for you for the rest of your life.\n\nFor quite a lot of girls their virginity was the greatest treasure they ever had and giving it away was a very big thing.\n\nNowadays we have a culture of law instead of honour and we have forms of social security and employment opportunities for single women and paternity tests and a lot of other things that make the worth of ones virginity much less of a life or death thing, the language that has built up around it however survives."
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2wd85s | why is getting water in the car engine bad? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2wd85s/eli5_why_is_getting_water_in_the_car_engine_bad/ | {
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"A car engine will compress air to about a tenth of it's volume before firing. If it sucks water in it cannot compress it. The momentum in the engine will cause the crankshaft to twist or the cylinderhead to fail."
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28nbte | why is the un often accused of being corrupt? | Also how much has the organisation actually helped in the areas of peace and human rights? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28nbte/eli5_why_is_the_un_often_accused_of_being_corrupt/ | {
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"Because the UN board has permanent members and rotating members. The permanent members (US, russia, etc.) can veto involvement in places where it isn't in their best interest (also why Taiwan can't claim sovereignty). "
]
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[]
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21rlqi | what would happen if a plane tried taking off in an extremely hot atmosphere? like surrounded by fire | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/21rlqi/eli5_what_would_happen_if_a_plane_tried_taking/ | {
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"Taking off when it's hot requires a faster takeoff speed, because hot air is less dense than cold air.\n\nFireballs usually travel **much** faster than an aircraft, so no, that wouldn't work.",
"A plane certainly couldn't operate inside a fireball, and it probably wouldn't go very far in a hot atmosphere like the one you described either. Looking just at the engine, the fuel would likely break down fairly quickly due to the increased heat which would mean the engines would not be able to produce enough thrust to keep the plane in the air. The engine oil would also break down, leading to failure of the bearings and then catastrophic failure of the engine. Raise the outside temperature high enough and the engine will begin to melt, although by that time the pilots, crew and passengers would probably be melting themselves. \n\nThat being said, planes and engines are more robust than most people imagine. You may be able to get away with flying through a relatively thin wall of fire, or a short exposure to a hot atmosphere, without suffering too much damage. \n",
"They would be delayed. Just like flights out of Phoenix on reallly hot days when the air is too thin for jet engines to perform within acceptable envelopes."
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3lm98t | what happens in your brain when you are reliving a memory and stop paying attention to your sight. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3lm98t/eli5_what_happens_in_your_brain_when_you_are/ | {
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"If you've ever seen the Tim Burton Batman, there's a scene where the Joker breaks into a news broadcast, disrupting the programming that was originally playing. (There are other movies that have done this, but this is the first one that I remember.) The same thing happens in your brain, because memory isn't stored in some filing cabinet in a discrete location. Memory is composed of semantic and sensory details, and reliving a memory often involves the same areas of the brain. Since our eyesight and smell is the strongest of our senses, most of the sensory information of our memories involve that part of our brain. The thing is, our brain only has so much \"bandwidth\" to handle this information, so when a memory is recalled with enough strength, we sometimes \"space out\" or abandon the present. In people with severe PTSD, the memories are so intrusive that they're distressing, because while most of us can shake a memory off and go back to what we should have been doing (driving, listening to your spouse), someone with PTSD has a very, very hard time doing this. If the memory is traumatic enough, it can be recalled as a flashback; a memory so intense you interpret it as reality.",
"This one is surprisingly simple: \"visualizing\" something activates the same brain areas as actually seeing it. \n\nIn [this study](_URL_1_), for example, monkeys were trained to associate an arrow with visual motion. After the training, the arrow alone activated neurons in area MT, which normally respond to motion. \n\nWe don't know nearly as much about most senses as we do about vision, but the principle is very likely the same: imagining a thing and actually perceiving it are represented in the brain in similar ways. This means that remembering an experience activates purely \"sensory\" areas of the brain - areas that were once thought to do nothing but process input from the ears, eyes, etc.\n\nWhat's still a mystery AFAIK is how the two are different. Most people can easily distinguish between imagining something and actually seeing it happen, although it may be a problem for [some people](_URL_0_). Suppose the same \"sensory areas\" of the brain are active whether you're imagining something or it's right there in front of you. But there has to be *some* difference. Are the same sensory neurons responding differently to those two situations, or is your imagination sending another signal to some other part of your brain, to let you know that what's going on in the sensory part of the brain isn't real? (Pretty sure no one knows this, but I'd love to be proven wrong.)\n\n\n\n\n",
"Do people actually see things in their mind? When someone asks me to picture something, I'm assuming they're not being literal because I can't actually conjure an image in my mind. Is this a thing people can do?",
"If the images or sounds are real enough, the body can't tell the difference between the memory and present reality, and all the emotions can get triggered. \n\nA similar thing happens watching movies when your body gets excited and scared by a two dimensional image that you know is not happening, at least in the beginning. The image and its sounds become your reality in that moment. Sound is a dominant sense where emotions are concerned. Sight will engage your analytical side, but sound will knot your gut. Many of my Vietnam vet friends had severe PTSD triggered by sounds, some by touch.\n\nCheck out The Brain series on _URL_0_. The research on memory is fascinating."
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46tov7 | how would this (cost effective 3d printed houses) affect the economy and housing prices in america's future when america starts doing it? | [story](_URL_0_)
So would that mean most people would be able to afford a big house because that mansion cost about $171,000 . Where im from you cant even afford a townhouse for that much.
are like mansions going to be the norm for living standards? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46tov7/eli5_how_would_this_cost_effective_3d_printed/ | {
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"The cost to actually construct a house is only part of the total price. The price is based on what people are willing to pay, which will depend heavily on how much demand there is for houses in the area. A house that might sell for $10,000 in Detroit might go for $800,000 in San Francisco. It's not because it costs 80 times more to build a house in SF, it's just that there are far more people wanting to buy a house there than there are houses available, while Detroit is the complete opposite. Much of what you're paying for in SF is the land itself, because there are only so many housing lots in the city. ",
"A house is not just walls and roof. When you buy a house, you buy insulation, pipes, wires, air conditioning/furnace, windows, doors etc etc etc - it can't be 3d printed and cost tons of money.\n\nSo nothing's going to change.",
"its not the house itself as it is the property the house is located on. 10000 square feet in lincoln nebraska is much cheaper than 10000 square feet in manhattan. cheaper conztruction wouldn't change this much. there have already been tons of improvements over the last century to make construction quicker and cheaper, such as drywall replacing plaster, prefabricated insulated roof panels, and even prefab foundations. 3d printing is another step in this direction. all of these have made bigger, more spacious housing cheaper and more common. "
]
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8d0e06 | if diet alternatives to sodas are so common, why aren't there more "diet candy"? is it harder to produce? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8d0e06/eli5if_diet_alternatives_to_sodas_are_so_common/ | {
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"There are tons of sugar free candies produced. The issue is that the volume of sweetner needed to make candy appropriately sweet also tends to act as a laxative for many people. So you mostly see long lasting candies like hard candies and gums made with them rather than fast eating candies like chocolates or gummies (though they did have gummy bears for a while). ",
"Because there are no suitable alternatives that work well. Things like lollipops are basically just sugar, taffy is just sugar with some water to make it soft, gummy bears are just sugar and gelatin.\n\nWith these candies, sugar is 80-90%+ of the content, the artificial sweeteners are far too strong to work and if used the candy must be made out of almost nothing but fillers. I'm not aware of any fillers that give the proper texture and dissolve in your mouth as sugar does.\n\nThe ones that do exist are made by replacing the sugar with sugar alcohol, which has roughly the same flavor and texture, but it's basically just indigestible sugar, and it acts like a laxative (but they make stuff, like sugar free gummy bears with it). Some products can use Xanthium gum or other thickeners to get water pretty thick, so up to the thickness of jello, sugar free is doable (they make sugar free maple syrup this way). But you can't use it to make water rock hard like a lollipop.\n\nSoda is practically all water, so swapping out the sugar for artificial sweeteners makes it slightly thinner which you might notice, but it doesn't destroy the effect.",
"Most non-nutritive sweeteners (\"artificial sweetener\" doesn't include things like stevia which are natural) are *vastly* sweeter than sugar so you don't need near as much to get the same amount of sweetening power. Aspartame, for example, is 200x stronger than table sugar by weight.\n\nRegular soda is water + sugar + flavor. If you replace the sugar with something else, it's still just sweet water. It might have a slightly different mouthfeel but nobody's really going to notice much.\n\nMost candy, however, uses sugar to make up the physical structure of it. If you take all the sugar out of a Jolly Rancher, there's nothing left. Finding stuff that you can make candy out of that *also* has no calories and doesn't have negative affects on your digestive system is a bit trickier.\n\nBaked good, like cookies and cakes, are even harder to strip calories from. "
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193muw | How does the eyepiece on Google Glass work? | How can you see the "screen" part, when it is completely transparent?
It has only a bit to the side where the light can come from [(pic)](_URL_0_), so there must be some kind of optical magicry going on somewhere. | askscience | http://www.reddit.com/r/askscience/comments/193muw/how_does_the_eyepiece_on_google_glass_work/ | {
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"I imagine it would use technology similar to [aircraft Heads Up Displays](_URL_0_)."
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1gxs67 | Why are lions and tigers considered separate species if they can produce fertile offspring? | Isn't the ability to produce fertile offspring the defining characteristic of a species? This is why all dogs are the same species, while horses and donkeys are separate, right? | askscience | http://www.reddit.com/r/askscience/comments/1gxs67/why_are_lions_and_tigers_considered_separate/ | {
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"No, ~~dogs and wolves~~, for example, can produce fertile offspring but are different species. Same with domestic cats and several species of jungle cats. *(I stand corrected, indeed, dogs are a subpecies. The cat example is still good though)*\n\nSome of the ways speciation can happen is through geographic separation (eg, migration to island) or behavioural separation (eg, one group mates in winter, other in summer).\n\nHowever, species is not a clean-cut word. There are problems defining it among experts. You can read more _URL_0_\n\nEDIT: I guess I didn't answer the actual \"Why\" of your question. The reason tigers and lions are different species is because of different behaviours, different habitats, different social hierarchies, and they each have their own subset of genes that they share within their species (like the genes for stripped fur or for manes).",
" > Isn't the ability to produce fertile offspring the defining characteristic of a species?\n\nIt depends on your definition of a species. What you're describing is the popular biological species concept. However, that is simply one of about [26 or so definitions.](_URL_0_)"
]
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2jnm4z | ; in the event of a global disaster/disease etc like wwz or resident evil, how long would the internet be functioning? is there anything that would stop it at this point if you could reach an access point? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jnm4z/eli5_in_the_event_of_a_global_disasterdisease_etc/ | {
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"As long as there's power to the infrastructure. One of the first internets, ARPANET, was made to survive nuclear war. You need a working access point. If the power goes out and there's no backup generators, you wouldn't be able to connect. ",
"The internet would only function for as long as the computers that make it up are running. For example, if the webservers running reddit shut down for whatever reason, then reddit is no longer available to the internet, and the same applies to everything else connected. If your ISP's routing network is offline, then you and anybody else using the same ISP won't be able to access the internet."
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bbzj6i | how does bone cancer occur | I thought cancer cells moved through the blood? Are bones directly connected to vessels? Am i dumb | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bbzj6i/eli5_how_does_bone_cancer_occur/ | {
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"Bones are alive! They are indeed connected to the blood stream and actually play an important role in the development of the immune system. But they also contain living cells, wich can sadly become cancerous with various consequences.",
"Bones are actually the origin of most of your body’s ability to generate blood (hematopoiesis) within the bone marrow and they are highly vascularized (connected to blood vessels). It seems strange as we think of bone as very hard/dense and static but bone is constantly remodeled and recreated and in this process our body makes small canals through the bone so blood vessels can penetrate deep into bones (called a Haversian canal). \n\nInterestingly, as osteosarcoma begins and the bone cells become malignant (cancerous) they usually spread to the lungs which seems very strange. But considering both bone and lungs are highly vascularized, it makes sense and the cancer is actually spreading through the blood. Other organs of high blood supply are also at risk of metastasis (spread) such as the brain. \n\nMy favorite histology slide type is a bone slide prep and here’s just some interesting info too: \n_URL_0_."
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1fjskw | What's the best way to finding information on Confederate soldiers who fought in the American Civil War? | I live in rural Virginia and recently while hiking in the woods near my house came upon a confederate grave with a man's name and his unit. I searched and found very limited information on his history. What's a good source for finding information on Confederate soldiers? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1fjskw/whats_the_best_way_to_finding_information_on/ | {
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"Fortunately you have all the information you need to find the man and his military records. You might get lucky and find him in the [Soldiers and Sailors database](_URL_1_) which is administered by the National Parks Service. You can also make an account at [_URL_5_](_URL_2_) and run a search on their databases, but I think they just cross reference other official sources. Then there is [_URL_0_](http://_URL_0_/) which has state by state roster listings, and of course the old standby of the [National Archives and Records Administration](_URL_4_)\n\nCivil War records are very well preserved, researched, copied and digitized. With a name and a unit, you'll have no problem at all finding his official military records. Did you take any pictures of the grave? It's possible if it's neglected grave, a fraternal organization like the Sons of Confederate Veterans, or even the State of Virginia or the Federal Government would offer help in restoring it. Good luck with your search!"
]
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"http://www.archives.gov/research/military/civil-war/",
"Ancestry.com"
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2fza5m | how did i just drive normally for 20 minutes while lost in thought? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fza5m/eli5_how_did_i_just_drive_normally_for_20_minutes/ | {
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"Your brain is really, really good at following routines. Things you do all the time, like driving a specific route, it can do on autopilot.\n\nThere was actually a study done where they took rats and measured how busy their brains were while they ran the same maze several times. After the first couple of runs, the rats had the maze down and their brains would go to a very low-activity state while they were negotiating it.\n\nBut I'm not saying it's safe to do that - you should probably avoid that \"lost in thought\" thing while herding a couple tons of steel.",
"Its kind of like being hypnotized/meditating. \n\n_URL_0_",
"You are actually paying attention, it is just nothing interesting enough to commit to long term memory is happening, besides what you were thinking about.",
"Muscle and mechanical memory also have a lot to do with it - it's the same way you can boil a kettle and make coffee while actively having a conversation, why a lot of smokers have a hard time quitting because they're so used to the mechanical action of picking up and inhaling, and why a lot of bachelors (like me) can shit / shave / shower in the morning when still drunk / badly hungover the following morning.\n\nConsequently, there's a whole niche of human error (written about mostly by James Reason), which defines how people manage to screw things up that they've done 1,000 times before on a daily basis, such as slips and lapses.\n\nSource: career in offshore oil and gas safety."
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5utski | Why did more Jews in France survive the Holocaust then in Belgium and the Netherlands? | So, I read some discussion on the sentiment "Petain did nothing wrong" - the main argument being: "Thanks to collaboration a lot more Jews survived then in Belgium and the Netherlands".
Which made me curious: Why did more of the Jews survive in France?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5utski/why_did_more_jews_in_france_survive_the_holocaust/ | {
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"There is a seeming paradox concerning Vichy and the fate of France's Jewish population during the occupation. On one hand, the survival rate of Jews in France was far higher than that of the Low Countries. Only a quarter of the Jews in France were deported, compared approximately 78% of the Netherlands and 45% of Belgium's Jews. These lower numbers were known at the time and Vichy officialdom seldom met the German quotas for deportation, much to the consternation of the SS and other German officials. Conversely, Vichy was far more proactive in its antisemitic measures than arguably any other German ally or occupied power on the continent. Vichy's justice ministry enacted laws restricting Jewish professional life and citizenship and the Vichy press gave free reign to all sorts of antisemitic invective. Many of the leading intellectual and political lights of Vichy were highly antisemitic and these attitudes seeing Jews as alien and un-French predated 1940 and continued into the postwar period. Additionally, of that 25% of Jews deported, the Vichy police and other French state officials did the majority of the work. Yet, a closer examination of both Vichy and the occupation reveals that this particular paradox is not so mysterious. The relatively high survival rate of Jews in France, both French- and foreign-born, had more to do with a unique constellation of factors ranging from timing, occupation boundaries, and social factors. \n\nFrance was unique among the Third Reich's victims in that it was the sole great power to surrender to German occupation. This immediately set German occupation policies apart from other examples like Belgium or the Netherlands. In those two latter examples, the largely urban and geographically smaller countries were more suited to a more hands-on occupation. Belgium, for example, came under direct military government while the Netherlands became the site of a turf wars between the *Reichskommisar* Seyss-Inquart, local Dutch fascists, the SS, and the bvarious military commands. In both of these cases, as in Denmark and Norway, the native civil service remained roughly intact an there was a small political group of native collaborators willing to be up-jumped into limited political power. But here, Germans remained in executive control, even if it was characterized by the polycratic infighting typical of the Third Reich. \n\nFrance was different. Under Petain, the French possessed a modicum of control both over the state and France's colonies. This relative independence was a byproduct of the confused German response to their total victory in 1940. In short, Germany suffered from a wealth of plans to deal with France in the aftermath of *Fall Gelb*. Some conceived of a fascist France aiding German hegemony, while still other Germans envisioned a partition of France into Aryan sub-states like a Norman state. Between these two poles was a more extemporizing consensus that sought to make occupation policy suit immediate needs off the war effort and German state policy. This middle position, which was far from coherent, meant that there needed to be some form of French executive. Additionally, the size of France and the limits of German manpower meant that there needed to be some native leadership to make the occupation run smoothly. \n\nWhat this meant for Vichy's Jewish policy was that the French was to an extent a master of its domain, even if the threat of German intervention hung like a cloud over Vichy policymaking. The results did not speak well for Vichy's moral standing. The motley of rightists in Vichy such as *Action Française* ideologues constructed a civic order that redrew French citizenship to include Jews and the overall tone of Vichy policies considered Jews to be a foreign body inside France. Foreign-born Jews like the novelist Irène Némirovsky were the early target of French ire as stateless Jews, and were over-represented among the 25% of Jews deported from France. This was of a piece with the Low Countries, which had a higher-concentration of non-indigenous Jews such as Anne Frank's family, who emigrated to the Netherlands in the mid-1930s. Yet French control over the Jewish citizenship meant there was an extra layer of bureaucracy for the Germans to contend with when they began in 1942. Other areas of occupied Europe presented less bureaucratic friction, so it was not surprising that the Germans tried there first before dipping into rendering France Jew-free. \n\nThe size of France also meant that it was much harder for both Vichy and the Germans to get a complete handle on the Jewish question in France. As seen in [this map](_URL_0_), the occupation was a mess of multiple zones adn restrictions ranging from the *Zone libre* of southern France, which was not under direct German occupation to Alsace-Lorraine, which were new *Reichsgaue*. This created different jurisdictions and accentuated the rivalries that were inherent to Nazi rule. The jurisdiction that was to be the savior for many Jews in France was not *Zone libre*, but rather the Italian occupation zone in Provence and Savoy. Although Vichy did much to restrict Jewish movement and resources, it was possible to move to a safer zone. Jews in smaller geographic entities like Belgium did not have this option. \n\nThe comparatively late timing of deportation, ca. 1942, also encouraged a number of Jews to flee to safer areas. Although actual knowledge of genocide was far from concrete, there was a genera sense that bad things were happening in the East and that it would be best for Jews to avoid this fate. The dissolution of the Italian zone after September 1943 removed the last real sanctuary for Jews in France, but it also gave them time to prepare either by going into hiding or forging papers. \n\nThe response of Vichy to Jews disappearing was far from sanguine. Vichy officialdom and various French institutions like the Catholic Church were either hostile or indifferent to the fate of the Jews, but the opening waves of deportations did arouse some resistance among gentile French. This was the excuse many Vichy officials gave to the Germans when deportations fell short. There was an element of truth to these explanations. Try as it might to turn back the clock to a pre-1789 conception of Frenchness, Vichy could not break the concepts of civil society that had characterized much of the Third Republic. French Jews were highly assimilated into French society and although antisemitism was quite strong in many French quarters, French Jews had social connections and capital which aided them in this period. Although French civil society was anemic and suffered from the twin burdens of Vichy and the material dearth of occupation, it still existed. Moreover, by mid-1942 and especially by 1943, there was one salient fact that many Europeans began to appreciate: Germany was going to lose the war. Around this period, for example, the Polish Home Army began issuing declarations that its was in Poles' interests as good Catholics to shelter Jews. This did not necessary mean that waning German fortunes stoked the embers of philosemitism; many Polish leaflets calling for sheltering the Jews also stressed they were a foreign entity that had exploited Poles in the past and would need to find a new home after the Germans had been thrown out. A good many Europeans recognized that saving someone from German aggression was an insurance policy for the postwar period when someone might go poking around in their more than questionable actions during the period of German hegemony. Such actions seldom translated into a mass numbers of Jews being saved from deportation, but rather loosened the net somewhat for the Vichy officials responsible for the *Aktion*s. \n\nIt also needs to be stressed that many Jews themselves took their survival into their own hands. The size and geographic variety of France, especially in the rugged south, lent itself well to disappearing. The relative lateness of the deportation also meant that many Jews found themselves into resistance bands. The French resistance, which had only really started to grow with Barbarossa when French Communists started fighting *en masse*, was accommodating to some Jews fleeing the deportations, especially the adolescents and other youth. Like other elements of the French polity, the resistance (which was also incredibly heterogeneous) was not philosemetic, but secular traditions in French civic society and the assimilation of French Jews meant that Jews were not an automatic other in resistance circles as they were in Eastern and Central Europe. The upsurge in resistance by 1942 thus dovetailed with the deportations. \n\nThis synergy and others like it helped many Jews within France to escape the Holocaust. But of this constellation of converging factors, the collaborationist government in Vichy did not play an active role in lowering the number of Jews murdered by the Third Reich. Vichy's actions made the plight of France's Jews much worse, whether by restricting their professional options or monetary resources and denying Jews the rights of French citizenship. The actions Frenchmen took to save Jews from murder often took place *in spite* of the government's actions, not because of them. The Vichy assault on the Third Republic's definition of citizenship and civil society and its uncoerced antisemitic legislation illustrate that many within the corridors of power in Vichy had a vision of a France that would not include Jews. At best, the Vichy government created a bureaucratic friction that made German deportations late and not as efficient as other zones where German control was more concrete. There were many direct factors that went into Jews' survival in France, collaboration was not one of them. \n\n"
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db84oq | how does a bank adjust its accounts after a robbery. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/db84oq/eli5_how_does_a_bank_adjust_its_accounts_after_a/ | {
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"A bank will file for their insurance benefits that they have for this very scenario. Maybe some banks just write it off as an expense in small cases of petty theft.",
"It does not. Your bank account is not a pile of money the bank keep for you, it is a loan you grant to the bank. If they loose the money in a robbery or on the stock market, they still owe you the full amount.",
"The money in the vaults isn't tied to anyone personal accounts. It's just a way to help people liquidate what's in their accounts. All of our money in our accounts right now is virtual in that sense. So it's just the bank's money until someone comes in and asks for a withdrawal. \n\n & #x200B;\n\nSo if someone steals it its just the bank that has to note \"hey this much money was stolen from us\" and then they file an insurance claim. But most bank robberies usually only get a couple thousand dollars. When I was a teller we had rules about how much cash we could have in our top drawer and that's what you can grab the fastest. All of us working together would only be a few thousand dollars and even if you force open the big safe there's not that much beyond that. \n\n & #x200B;\n\nFor something like safety deposit boxes where people do put personal property, I'm not sure. I'm sure the bank has general insurance on those but someone keeping something really valuable in a box like that ought to have their own policies specifically mapped to whatever is in there.",
"The bank would have all it's cash money in a balance sheet assets account as \"petty cash\" or \"cash on hand\". All of the individual peoples accounts would be in a liabilities account as \"peoples bank accounts\". If the bank needed to reduce it's \"cash on hand\" asset account it wouldn't effect the \"people's bank accounts\" liability account. They would just reduce the asset and then show the hit on the income statement."
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2e7mzm | How are new starts formed from the remains of an exploded star? Aren't they mostly Helium/Oxygen/Carbon dust? Don't new stars require Hydrogen? | Or does the explosion cause the elements to break back down to H? | askscience | http://www.reddit.com/r/askscience/comments/2e7mzm/how_are_new_starts_formed_from_the_remains_of_an/ | {
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"Two things here.\n\nFirst, when a star explodes at the end of it's life, it's still mostly hydrogen. The only part that has been transmuted to helium and heavier elements is the core, where the pressures and temperatues are the highest.\n\nSecond, new stars get most of their material from the clouds of hydrogen already in interstellar space. Those clouds get enriched in heavier elements when a supernova happens nearby, but most of the hydrogen that eventually makes up the star is already there."
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8q1tvb | why does the rain make plants and stuff look more green? | Is it just because the darker wet bark contrasts with the leaves and makes it look greener? Or does the rain wash off dust or something? Or does it look greener for the same reason wet bark is darker? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8q1tvb/eli5_why_does_the_rain_make_plants_and_stuff_look/ | {
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"It does indeed wash off the dust. It also coats over the rough surfaces, which contain tiny hairs (and other rough materials) that make the colors look a bit more grayish.",
"I think leaves absorbing water also changes which wavelengths (color combo) are reflected. This idea is used to retrieve vegetation index from satellite data."
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54adxv | For how long did pre-Civil War South Carolina restrict its citizens from partaking in national elections? | Currently doing some work for my American Civil War class at the moment and I came across a section in my textbook discussing the ideology of the South leading up to secession, specifically discussing the influence of John C. Calhoun on states such as South Carolina. It mentions outright that South Carolina was the only state in the Union to disallow its citizens from partaking in national elections, as the electors were chosen by the legislature rather than by a vote. For how long prior to 1860 had this system been in place? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/54adxv/for_how_long_did_precivil_war_south_carolina/ | {
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"Having the legislature appoint electors for the presidency was the done thing in South Carolina for every presidential election up through 1860. It used to be more common elsewhere, but the increasing acceptance of the white man's popular democracy as the nineteenth century went on made legislative appointments seem increasingly out of step with the times. In a way, that's what SC was going for. They held on to the elite-directed eighteenth century politics style really hard, trying to recapture their dream of the English country gentry (but with slaves) perfected a century later in the New World. I've read SC politicians saying they don't expect their voters to ever think much about politics, just which leading man of the community they preferred. The main exception is that they liberalized the franchise a bit early. \n\nCalhoun's the obvious go-to guy when talking about antebellum anti-majoritarianism, but it's worthwhile to keep in mind that in the SC context Calhoun is frequently a moderate and that the sole minority which concerns him (or really any of these guys) is white slaveholders. Where King Numbers doesn't seem so perilous to slavery, or might be useful in advancing the peculiar institution, principles frequently change. Nor does SC-style anti-majoritarianism often play well outside the state in the later antebellum. The dominant political style is usually Jacksonian herrenvolk (master race) democracy."
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1fjxl0 | If pieces of my hair fall into open wounds (like during brain surgery) what happen to them? How do they get out of my body? | I wanted to ask after watching this video.
_URL_0_ | askscience | http://www.reddit.com/r/askscience/comments/1fjxl0/if_pieces_of_my_hair_fall_into_open_wounds_like/ | {
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"Ideally it should never happen- everyone is wearing some sort of hair cover, whether it is a bouffant, surgeon's hat, or a custom cap. However, if it did happen, and the hair fell into a surgical wound, ideally it should be spotted by someone at the table and it would be carefully removed. There are protocols for if there is an accidental non-sterile foreign body introduced to a surgical wound, and typically it's close surveillance and use of broad spectrum antibiotics like cephalosporin.\n\nSo what happens if goes unnoticed? Hair is just keratin, which is just protein. The body normally has proteases that are found in all tissues and circulate through the blood stream, and can be activated in pro-inflammatory states. Eventually the hair would break down into constituent amino acids. However, the danger is that because it's a relatively complex structure and a contaminated foreign body, there is a good chance it could act as nydus for infection. If left in soft tissue, it would eventually granulate, and either become an abscess or a scar. If left deeper, such as in a bone, it could act as a nydus for osteomyelitis, which is a life-threatening bone infection. If left in a vessel, it could, in theory, act as an embolism (not unlike an amniotic embolism). The brain would be particularly problematic, as it's a closed space. If it does become a nydus, it could become a brain abscess, which can be disasterous, as the head is a closed space, so the only way to expand the abscess is to compress the brain, and in addition cause an encephalitic response."
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js9t8 | how sat's are supposedly "slanted against african-americans" | Apparently people think this. I don't understand how someone can slant a question so that, due to someone's skin color, they will answer incorrectly. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/js9t8/eli5_how_sats_are_supposedly_slanted_against/ | {
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"[Stereotype threat](_URL_0_). Knowing that there is a stereotype out there that your race (or gender) isn't as good at what you're currently trying to do makes you stress out about confirming the stereotype if you do badly. Stressing out during a test makes you do worse.\n\nExample study: they took a group of people including white and black people, divided them into two groups randomly so that both groups had black and white people in them. They had them do a minigolf course (the same minigolf course for both groups), and they told group #1 that their performance would reflect their level of spatial intelligence, while they told group #2 that their performance would reflect their level of athletic ability. Group #1 had white people doing better than black people, group #2 had black people doing better than white people. The exact same course for both groups.",
"Like Graendal said, stereotype threat is one example. The other is that the SATs are written in a way that assumes a very specific kind of knowledge, one that is most often found in middle-or-upper class contexts and among European-Americans. By which I mean--asking questions that presume a certain way of thinking, or that use cultural touchstones, or that use terms or words that are used in \"classic\" English texts, etc. \n\nNot only did the test start out racist and sexist, but efforts are made to keep it slanted toward richer white students. The SATs constantly test new questions out on students (that's the ungraded section). They throw out the ones that black students are more likely to answer correctly than white students, but keep the ones white students are more likely to answer correctly than black students. \n\nJust googling \"SATs\" and \"racism\" will get you a lot of this information, but an easy to understand and well-researched essay on the topic is [here](_URL_0_).",
"Consider this question:\n\nCup is to saucer as plant is to ______\n\nA. Leaf\n\nB. Stalk\n\nC. Root\n\nD. Flower\n\nSeems like a simple, fair, and straightforward question, right?\n\nWell, what if you grew up in a poor home, where you didn't have matching sets of cups and saucers? What if you grew up in an inner city area where you don't see a lot of plants? What if English is your second language?\n\nYour background will make it harder to understand what the question is getting at. It has nothing to do with skin color itself, but with cultural and economic factors often linked with race. ",
"I'm going to have to break the mode of ELY5 because there appears to be a fundamental interpretation error.\n\n\"slanted against african-americans\" does not equate to \"racist\", which is what you appear to think in your responses to well-written comments. Correct me if I err.\n\nNeither does it mean that\n > due to someone's skin color, they will answer incorrectly\n\nAs you state, that would be racist because your statement claims that the person's race **causes** them to answer incorrectly. ([Relevant](_URL_0_) and amusing). However, this is not what \"slanted\" means.\n\n\"Slanted\" in this context means that some people are more likely (holding other relevant factors constant) to get a question wrong if they are of a certain group. I repeat, \"more likely\" is claim of correlation, **not** causation. Since there are cultural and socioeconomic factors at play when interpreting questions of the SAT *and* the SAT is supposed to be independent of those two factors (among others), it is possibly correct to say that the SAT is \"slanted\".\n\nNow that I've said that, here's the ELI5 version:\n\n\"slanted\" doesn't mean racist. The people who write the test would obviously get fired if they wrote mean questions like that. Sadly, sometimes just because you're from a certain family, or just because you're poor, you know different things than if you were from a different family. Sometimes you don't even you know different things. And it's important to know that knowing different things doesn't mean you're better or worse; it's just different. The people who write the SAT are usually from better-off families and so when they write the questions, they write questions with words they understand and sometimes other people don't know those words.\n\nTake your friend Jimmy from school for example; his family doesn't use expensive china because they can't afford it. Your friend Spencer's family uses his great-grandmother's china. I'd be willing to bet that out of 1000 Jimmys, fewer would know what the word \"saucer\" meant compared to 1000 Spencer. It's just what words they know; it doesn't mean Spencer is better than Jimmy.\n\nNow in the real world, because people don't always see things clearly, black people had it really hard in America in the past because white people were mean to them. Now things are better, but black people are still catching up. Again, we know they aren't better or worse for it; it's just the effects of history that are still around.\n\n(I hope the ELI5 version isn't racially charged too badly…)",
"[Stereotype threat](_URL_0_). Knowing that there is a stereotype out there that your race (or gender) isn't as good at what you're currently trying to do makes you stress out about confirming the stereotype if you do badly. Stressing out during a test makes you do worse.\n\nExample study: they took a group of people including white and black people, divided them into two groups randomly so that both groups had black and white people in them. They had them do a minigolf course (the same minigolf course for both groups), and they told group #1 that their performance would reflect their level of spatial intelligence, while they told group #2 that their performance would reflect their level of athletic ability. Group #1 had white people doing better than black people, group #2 had black people doing better than white people. The exact same course for both groups.",
"Like Graendal said, stereotype threat is one example. The other is that the SATs are written in a way that assumes a very specific kind of knowledge, one that is most often found in middle-or-upper class contexts and among European-Americans. By which I mean--asking questions that presume a certain way of thinking, or that use cultural touchstones, or that use terms or words that are used in \"classic\" English texts, etc. \n\nNot only did the test start out racist and sexist, but efforts are made to keep it slanted toward richer white students. The SATs constantly test new questions out on students (that's the ungraded section). They throw out the ones that black students are more likely to answer correctly than white students, but keep the ones white students are more likely to answer correctly than black students. \n\nJust googling \"SATs\" and \"racism\" will get you a lot of this information, but an easy to understand and well-researched essay on the topic is [here](_URL_0_).",
"Consider this question:\n\nCup is to saucer as plant is to ______\n\nA. Leaf\n\nB. Stalk\n\nC. Root\n\nD. Flower\n\nSeems like a simple, fair, and straightforward question, right?\n\nWell, what if you grew up in a poor home, where you didn't have matching sets of cups and saucers? What if you grew up in an inner city area where you don't see a lot of plants? What if English is your second language?\n\nYour background will make it harder to understand what the question is getting at. It has nothing to do with skin color itself, but with cultural and economic factors often linked with race. ",
"I'm going to have to break the mode of ELY5 because there appears to be a fundamental interpretation error.\n\n\"slanted against african-americans\" does not equate to \"racist\", which is what you appear to think in your responses to well-written comments. Correct me if I err.\n\nNeither does it mean that\n > due to someone's skin color, they will answer incorrectly\n\nAs you state, that would be racist because your statement claims that the person's race **causes** them to answer incorrectly. ([Relevant](_URL_0_) and amusing). However, this is not what \"slanted\" means.\n\n\"Slanted\" in this context means that some people are more likely (holding other relevant factors constant) to get a question wrong if they are of a certain group. I repeat, \"more likely\" is claim of correlation, **not** causation. Since there are cultural and socioeconomic factors at play when interpreting questions of the SAT *and* the SAT is supposed to be independent of those two factors (among others), it is possibly correct to say that the SAT is \"slanted\".\n\nNow that I've said that, here's the ELI5 version:\n\n\"slanted\" doesn't mean racist. The people who write the test would obviously get fired if they wrote mean questions like that. Sadly, sometimes just because you're from a certain family, or just because you're poor, you know different things than if you were from a different family. Sometimes you don't even you know different things. And it's important to know that knowing different things doesn't mean you're better or worse; it's just different. The people who write the SAT are usually from better-off families and so when they write the questions, they write questions with words they understand and sometimes other people don't know those words.\n\nTake your friend Jimmy from school for example; his family doesn't use expensive china because they can't afford it. Your friend Spencer's family uses his great-grandmother's china. I'd be willing to bet that out of 1000 Jimmys, fewer would know what the word \"saucer\" meant compared to 1000 Spencer. It's just what words they know; it doesn't mean Spencer is better than Jimmy.\n\nNow in the real world, because people don't always see things clearly, black people had it really hard in America in the past because white people were mean to them. Now things are better, but black people are still catching up. Again, we know they aren't better or worse for it; it's just the effects of history that are still around.\n\n(I hope the ELI5 version isn't racially charged too badly…)"
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33jgbo | why are there restrictions on liquid containers for planes? i know an attempted terror attack caused it, but how does it make sense? | [found this on r/funny](_URL_0_)
It's actually quite true, you can bring lots of small liquid containers, but not one big one. I know hydrochloric acid is a popular way of mutilating people and you could easily fit it into a tiny can of deoderant, or several cans of deoderant, so how would taking a large bottle of contact lens fluid really help things?
I'm convinced it's an elaborate charade to make sure I buy my liqours and liquids at the airport's shops | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33jgbo/eli5_why_are_there_restrictions_on_liquid/ | {
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"It does not make sense. It's only in the US, where TSA is a bunch of old guys on a power trip. ",
"On the contrary, Smaller containers = smaller amount of substance that is brought into the plane. Even if its a lot of bottles, n * 30ml of X substance (even if its water) is a controlled substance that is being brought into the plane. \n\n1) Very hard to make any quantifiable damage in such quantities.\n2) Quite a lot of effort needed to prepare N*30ml substances into 1 harmful substance. \n3) Harmful/Dangerous substances are usually spectroscoped as they are X-ray(ed) and they tend to light up like a Christmas tree in the software ... (even if there are loads of people carrying the same harmful substance in the airport, the software keeps count of this and there is a deterrent process in place). \n4) Really easy to make people just follow the guidelines, for general safety, but in the process scaring the shit out of them.( but that's collateral damage and capitalism can exploit that if its wants to) \n\noh and aerosol-ing (Proudly invented word ) acid is very hard, the pressures needed would be quite high, and quantity, not that high to do significant damage. You'd need about 20 cans or so that are allowed by the airports to go through, in order to make some dent in security concerns.",
"The reason for the ban on containers of liquid is due to the possible use of liquid binary explosives. When you are getting ready to board a plane alot of times you will be subject to scanners and bomb sniffers. Because binary explosives aren't detectable until they are mixed in a lot of cases they can slip through the screening process. You can make an explosive powerful enough to blow a hole in the fuselage of a plane and cause rapid depressurizaton with as little as 16 ounces of binary explosive and new ones are always being synthesized so that number could very well be smaller."
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4jnxfc | are there any species that are both sexually and asexually reproductive? | If so, how do they fare? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4jnxfc/eli5_are_there_any_species_that_are_both_sexually/ | {
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"Well, many flowering plants are. They have both male and female parts, they can pollinate themselves, or others. And they fare pretty well.",
"There are some species that can alternate between both sexual and asexual reproduction. There are some insects such as Aphids that will sometimes lay eggs without fertilization thus cloning themselves. The Cape Bee can also do both. They do it mainly through a process called Thelytoky (when the eggs are laid and not fertilized but still produce). There are some species of amphibians, reptiles, and birds that a capable to. For example, the freshwater crustacean Daphnia reproduces by parthenogenesis in the spring to rapidly populate ponds, then switches to sexual reproduction as the intensity of competition and predation increases. Another example are monogonont rotifers which reproduce via cyclical parthenogenesis: at low population densities females produce asexually and at higher densities a chemical cue accumulates and induces the transition to sexual reproduction. So for some species it depends on the conditions they are in if they reproduce sexually or asexually."
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2pcblw | What are these lines? | Room temperature water put on high temperature burner for boil.
[Video](_URL_0_) | askscience | http://www.reddit.com/r/askscience/comments/2pcblw/what_are_these_lines/ | {
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"text": [
"What lines? I assume you don't mean the scratches on the bottom of the pan.",
"Water's density changes with temperature. What you are seeing is roiling temperature gradients caused by boiling. The turbulence consists of water of different density, bending the light that goes through it, and leading to the 'lines' you see,",
"What you're seeing is the difference in temperatures between two water masses. The index of refraction changes with density, so the light bends differently between the two bodies.\n\nThe cooler water on the surface is sinking toward the bottom of the pan because it's more dense (cooler water is more dense than hot water unless you're less than 4 degrees C). \n\nThe cooler water rolls to the bottom (because the heat is creating a convection cycle inside the pan). Because it has a different index of refraction you can see the leading edges of the cooler water mass. \n\nIf you stirred the pan it would mix the water masses and you wouldn't see those lines because the water would have a more uniform temperature."
]
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"https://vimeo.com/114529175"
] | [
[],
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|
aageh4 | i recently got into a physical altercation where afterwards i had to explain the situation and my voice was shaky and words wasn’t forming at all. no matter how hard i tried to slow down . and i tried to sit down and but my leg shook uncontrollably, why did those two things occur ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aageh4/eli5_i_recently_got_into_a_physical_altercation/ | {
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"Adrenaline dump. Your body reacted to a dangerous situation by dumping adrenaline and other hormones into your system, so that you could fight or fly. It can take an hour or more to clear. Your trying to calm a fire your body just poured gas on. You're also shunting blood from your brain, which you don't need right now, to other areas which you do, like your heart lungs and legs. Trying to describe it by visualizing the events keeps your body in fight or flight mode.",
"Fight or flight floods your body with chemicals that makes you run full throttle, and it may take a while for it to leave your system",
" I literally sounded like two people trying to talk over the phone at the same time",
"Adrenaline. In response to a sudden and dangerous event (like your altercation), your brain tells your adrenal gland to release adrenaline. The adrenaline gives you a rush of strength and energy to help you win a fight, escape from a tiger, etc. Immediately afterwards the adrenaline was still in your bloodstream so you still had extra energy. You couldn't shut it off until the adrenaline was gone, which is why you were shaky and jittery."
]
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[],
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||
2575z5 | How were native Americans able to survive in the Sonoran desert with such little water? | I've currently been reading on the culture of the Apache, Tohono O'odham, and Raramuri, as well as other indigenous cultures in the Sonoran desert region. They would grow corn, beans, and grains, but I'm curious as to how they utilized water conservation to accomplish this. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2575z5/how_were_native_americans_able_to_survive_in_the/ | {
"a_id": [
"cheh2yc"
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"text": [
"Since you're in the literary area, as something of an aside please allow me to recommend [Gary Paul Nabhan](_URL_0_)'s [\"Gathering The Desert.\"](_URL_1_) It's beautifully written and illustrated, and goes deeply into the lifeways of the Tohono O'odham people. If you haven't read it already I'm certain you'll find it enjoyable and informative."
]
} | [] | [] | [
[
"http://garynabhan.com/",
"http://www.uapress.arizona.edu/Books/bid327.htm"
]
] |
|
292kqb | cold welding in space | I recently read a short article about cold welding in space. Where if you touch to like metals together (ex copper on copper) they stick together. How and why does this happen? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/292kqb/eli5cold_welding_in_space/ | {
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"On earth, metals are almost always covered by a very thin film of oxide. This means that actual metal-to-metal contact is rare.\n\nIn space there is no atmosphere to provide oxygen, which would renew the oxide coating. When the oxide wears off, and you press the metals together, there is true metal-to-metal contact. Since the metal surfaces are not microscopically smooth, the pressure is all taken out on a small number of microscopic high spots, and the metals simply unite at these points.\n\nYou can try a similar effect in your own kitchen. Take a couple of ice cubes, let them warm up a bit, then press them together. They will weld into a single lump. Water already has all the oxygen in its molecule that it can accept, so it cannot oxidise further. ",
"So, you've probably heard of covalent and ionic bonds. In covalent bonds, the force of attraction that shared electrons cause binds atoms together. In ionic bonds, the positive charge of one atom attracts it to the negative charge of another.\n\nHowever, there's a third kind of bond: metallic. In metallic bonds, metal atoms are kept close to each other so electrons can freely move between them. The attraction between these electrons and all of the metal nucleuses keeps them held together. Metallic bonds are also responsible for the conductivity of metals.\n\nSo, if you touch any raw metal to another raw metal, they will fuse together instantly in a metallic bond. But this obviously doesn't typically work on Earth; otherwise, we could just press metals against each other to weld them together. If a metal is exposed to oxygen (of which there's an abundance in our atmosphere), its outer surface will oxidize -- the metal will form covalent bonds with oxygen. As electrons cannot flow through covalent bonds as easily as they can through metallic bonds, the whole contact-fusing property is done with. It only works when two metals can bond with each other and oxygen makes that impossible. What welding on Earth actually does is it burns away those oxygen bonds on the outer layers of metals and lets the raw metals fuse with each other.\n\nNow, if we were to remove the oxygen-laden atmosphere -- say, put the raw metals in space -- then we don't have to worry about covalent bonds and can just tap metals together to weld them. This would also work in a vacuum chamber on Earth, but it sounds a lot cooler to weld *in space*.\n\nThis is my first ELI5 answer. If you need any more clarification, just ask."
]
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[],
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] |
|
5bjurd | Were there significant amounts of refugees as a result of the American Revolutionary War, War of 1812, and Civil War? | We've see staggering amounts of refugees as a result of recent day wars and conflicts. I can't remember being taught of refugees that resulted from the wars that took place on American soil. Did those result in the migration of refugees, or did the population put up with the conflict? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5bjurd/were_there_significant_amounts_of_refugees_as_a/ | {
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"d9p5t6l"
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"text": [
"To come at this from a slightly different angle:\n\nDid the Civil War significantly drive westward migration after the war? I'm thinking freed slaves, Confederate veterans, or people who got uprooted by the fighting. "
]
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[]
] |
|
51b6ko | How representative is the composition of our solar system versus the composition of known exoplanets? | For instance, is a large gas giant like Jupiter representative of other gas giants? Are gas giants typically located towards the out portions of the solar system? Do rocky planets tend to have atmospheres like Venus and Earth or is Mars a more representative example? | askscience | https://www.reddit.com/r/askscience/comments/51b6ko/how_representative_is_the_composition_of_our/ | {
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"The solar system is quite different from the \"typical\" exoplanet systems we've seen so far, but that's because our methods for detecting exoplanets don't work well for systems like ours. Odds are good that our solar system is pretty typical of solar systems throughout the galaxy, but our exoplanet detection technology is highly biased.\n\nThe two main [methods of detecting exoplanets](_URL_0_), transit and radial velocity, both work best for very large planets located very close to a relatively small star, so most of the exoplanet systems we've found are of that type. Also, you need to take observations over a very long period to detect *all* the big planets in a system, especially those that are far from their star: we haven't been in the exoplanet game long enough to reliably detect distant giant planets like our Saturn or Neptune.\n\nOne good example of an exoplanet system that helps to answer your question is [Kepler-90](_URL_1_). This system appears to have seven known planets, ranging in size from Earth-size to Jupiter-size. The small ones are close in, the big ones are far out, just like our solar system. However, the whole system is packed in close to the star: Kepler-90's outermost known planet is as far from its star as the Earth is from the Sun!"
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Methods_of_detecting_exoplanets",
"https://en.wikipedia.org/wiki/Kepler-90"
]
] |
|
8rkkc9 | why do city birds sing at night? do the city lights prevent them from ever sleeping? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8rkkc9/eli5_why_do_city_birds_sing_at_night_do_the_city/ | {
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"Birds in/around large human populations usually adapted \"singing\" before humans wake up, simply due to the fact that their shouts will not be overwhelmed by the sounds of the cities... a Bird is much easier to hear at 5am than at 12pm or during rush hour... not only can WE hear them more, but they can hear EACHOTHER",
"Male Mockingbirds that don't have a mate will sing all throughout the night. It can be very annoying to humans trying to sleep! They mimic songs of other birds (and sometimes even alarm clocks and car alarms). "
]
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[],
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||
a1on3q | why dont humans replace teeth more than once like animals such as sharks do? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a1on3q/eli5_why_dont_humans_replace_teeth_more_than_once/ | {
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"Humans have bred all the children before their second set of teeth wears out. That means there is no evolutionary pressure to have more sets. Other long-lived mammals do have multiple sets of teeth, elephants for example have 6 sets, but the infinite regeneration seen in fish are not present in mammals, as far as I know.",
"Humans, like most mammals, only have two sets of teeth through-out their lives. This trait most likely evolved in mammals (many early mammal ancestors did grow multiple sets of teeth) because of the way we learned to chew our food. To be able to do that, you need strong, durable teeth that are ankered in your jaw. Else you just can't grind down food properly. So along our evolutionary line, we traded in the ability to grow multiple (less sturdy) sets of teeth in favour of having fewer sets up teeth that can go the distance, so to speak.\n\nIf you look at animals that replace their teeth frequently, you'll notice that they don't really chew their food. Most can't. They just tear and swallow things whole. ",
"Simple sharks do not have teeth.\n\nWhat we call a sharks tooth is in fact a modified placoid scale.\n\nAs it is a scale it regenerates regularly as all other scales do. \n\nHumans have teeth and all said teeth are present at birth.\n"
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3t4pym | When, and how, did mint become the universal "fresh" flavouring for mouth hygiene products? | In the western world today mint has a near monopoly on flavouring for things like mouthwash and toothpaste, whereas for example in Asia you can easily find lemon or other flavours, and I've heard that lavender and rose were popular in Europe up until around ww2.
Does anyone have any insight as to when and how the shift to mint happened? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3t4pym/when_and_how_did_mint_become_the_universal_fresh/ | {
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"While I can't answer that question from a historic point of view (which might get this answer deleted, I'm aware of that), I'd like to say a few things about the biochemical/neuroscientific basis of mint flavor.\n\n**TL;DR:** We are not \"conditioned\" to perceive mint flavor as fresh. The responsible molecules in mint actually do evoke a \"fresh\" sensation.\n\nYou see, usually \"flavor\" consists of two different neurochemical components. The first is the activation of taste receptors on your tongue - they are responsible for the five basic tastes: Sweet, salty, sour, bitter, and umami (savory/meat-like). But if you ever had food when having a cold, you know that this isn't all. The more complex flavor patterns are the result of the activation of olfactory (smell) receptors in your nose.\n\nBut there's a third class of receptors, which actually aren't considered taste or olfactory receptors. These are called the [TRP channels](_URL_1_), they are a rather large protein family, and they have several functions in the body. Two of these channels are interesting when it comes to taste, and these two are temperature-sensing. \n\nThe first is called [TRPV1](_URL_2_), and one of its functions is to detect heat. When your food's too hot, they activate and tell you it's too hot (in terms of temperature) by sending a pain signal. But the protein does not only get activated by heat, but also by capsaicin, the active ingredient in ~~pepper,~~ chillis, and tear gas. That's why \"hot\" (in terms of taste) is exactly that - a \"hot\" (temperature) sensation (Edit: not in pepper, that's piperine, which also activates TRPV1. Thanks to /u/BloomsdayDevice).\n\nThe other one is called [TRPM8](_URL_0_), and it's the equivalent \"cold receptor\", reacting to low temperatures. Now guess what also activates this receptor? Menthol, the active ingredient in mint. So it's not that at some point a company decided \"let's make mint the \"fresh\" flavor\", and everybody just went with it, but rather that there weren't really common alternatives to mint that activated the (at that point unknown) ~~TRPV8~~ TRPM8 ion channel.\n\nEdit: Spelling.\n\nEdit 2: Mixed up TRPV and TRPM in the last paragraph. Also, is thanking for gold encouraged or discouraged here? Anyway, thanks ;)\n\nEdit 3: Was wrong with pepper.",
"Hello everyone, \n\nUnfortunately, we have already had to remove a number of poor quality responses in this thread, including many asking about the deleted comments, which merely compound the issue. In this thread, there have been a large number of incorrect, speculative, or otherwise disallowed comments, and as such, they were removed by the mod-team. Please, before you attempt answer the question, keep in mind [our rules](_URL_0_) concerning in-depth and comprehensive responses. Answers that do not meet the standards we ask for will be removed. Finally, the only answer that was in any depth did mention the science behind mint, but did not address the historical question OP was asking.\n\nAdditionally, it is unfair to the OP to further derail this thread with off topic conversation, so if anyone has further questions or concerns, I would ask that they be directed to [modmail](_URL_1_), or a [META thread](_URL_2_[META]). Thank you!"
]
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4zxwyi | Jobs in the American Industrial Age | During the Industrial Age, plenty of immigrants settled in the booming cities to find jobs and lived in immense poverty. However, if working in industry was so money-less for the workers, how did the lower class among the "native" population (or essentially the decedents of earlier immigrants from the colonial times up to the Industrial Revolution) of the United States fair? I feel like they get excluded from the discussion regarding the Industrial Age. I've even read *How the Other Half Lives*, but I don't really recall any mention of lower class people who were not immigrants. I guess I have a broad question relating to the middle class and lower class of the time with respect to non-immigrants. What were their jobs? Surely there must have been more than *just* the factories, mining coal, or farming. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4zxwyi/jobs_in_the_american_industrial_age/ | {
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"I want to note from the outset that my answer, due to gaps in my own knowledge as well as a general tendency in the scholarship, is pretty focused on the Northeast, and is entirely focused on the White working class. There are important parts of this story that are about Southern Whites as well as Blacks, both before and after the Civil War. I hope someone can fill in that story.\n\nThe nineteenth century saw the transformation of the American economy from, as you are aware, a largely agricultural focus to a largely industrial one. For a native-born White man at the dawn of industrialization (the end of the eighteenth or the beginning of the nineteenth century), the most likely occupation was farm labor, usually on a family-owned farm in the Northeast, Old Northwest, or the South (particularly the Upper South). Gradually, these lands became less viable, due to soil exhaustion and partition of family farms into smaller and smaller chunks as a result of generations of inheritance. For the young men growing up on these farms, there were a couple main options: One was emigration, going either alone or with a young family to the newly-acquired territory in the West (this includes the Louisiana Purchase and all the land acquired from Mexico, plus the sections of the Oregon territory that ended up in the U.S. after the treaty with Britain). The other was to move to the city and join attempt to join the burgeoning middle class by acquiring work as a clerk in a mercantile house, eventually amassing enough money to start one's own business or otherwise join the ranks of the professionals (studying the law and, later in the century, medicine were also options for this route). However, this isn't really the \"working class\" in the industrial sense. \n\nThe working class is a creation of industrial capitalism. Before the widespread introduction of that mode of social organization and production, the urban producing classes were artisans. Organized in a manner very similar to the earliest medieval guilds, each trade would have had its own organization of master craftsmen, journeymen, and apprenticeship, and would have governed its own norms. This includes things like shoemakers, coopers, tailors, etc. Traditional norms would have governed their working lives, including a principal of independence for both shop owners and employees. Importantly, the \"management\" (ie the master artisans) would have closely identified with the workers. In other words, hierarchies were relatively flat, and there was a strong sense of a group of brother tradesmen working together. This included the right to stop working when one felt like it, to drink on the job, and to otherwise organize the day how one saw fit. What happened to this way of life? Industrial capitalism. As machinery increased the efficiency of production of basic goods like shoes, clothes, barrels, etc., it also decreased the skill required to produce them. This proved disastrous to the working class, who found themselves suddenly faced with an influx of immigrants willing to work for much lower wages operating the new machinery, causing severe downward wage pressure. Additionally, the capitalists took this opportunity to begin to assert greater control over the mode of work, requiring longer working hours with less freedom (including the banning of drinking on the job, or of the practice of knocking off for an impromptu holiday). The trade guilds fought back as best they could, forming the kernel of the American labor union movement. \n\nAs for what jobs they did, perhaps an economic historian will have actual numbers, but throughout the nineteenth century most jobs would still have been in farming. Resource extraction (mining, fishing, oil, etc) would have been big ones, as would manufacturing. You also have various labor jobs, like teamsters and longshoremen, supporting the import and export of all this raw material and finished goods. As I mentioned, for the emergent middle class you would have had the professions, like law, as well as accounting and the aspiration to ownership and upward mobility. Finally, there were a class of very low-paying, undesirable jobs like rag- and bone-picker, men who would walk the streets going through rubbish looking for rags (for papermakers) and bones (for soap-making as well as knife handles and the like). These were a group of true underclass, living in absolute penury and making the barest of livings.\n\nI hope this brings some clarity. Immigration levels were very high, and for the men who did not make it to the farms of the Midwest or into the middle and managerial classes, they would have been caught up in the same forces of industrial capitalism that swallowed up all the immigrants, though their relatively higher levels of social and actual capital would have actually helped. But do keep in mind that most labor was still agricultural throughout the nineteenth century. It was a process of urbanization and industrialization, rather than all-at-once.\n\nSources:\n\nWilentz, *Chants Democratic*\n\nBlight, *The Moneyed Metropolis*\n\nTrachtenberg, *The Incorporation of America*"
]
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|
1nenie | why are tobacco products behind the counter, while alcohol is on shelves in stores? | I don't understand why tobacco is behind counters and you have to be 18, and alcohol is on shelves in the store, available for everyone to see, but you have to be 21? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nenie/why_are_tobacco_products_behind_the_counter_while/ | {
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"text": [
"It's easier to steal a small package than a large bottle"
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1c8bwo | how can this guy drink this much alcohol at once at not die? | _URL_0_
I'm watching this video and apparently this guy Shoenice is the real deal. These aren't fake stunts. How in the world can one person consume this much alcohol at once at not die?
*Sorry for bad title, meant to put and instead of at. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1c8bwo/eli5_how_can_this_guy_drink_this_much_alcohol_at/ | {
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"I have to assume he immediately went and threw it all up. It would probably kill him if he didn't.",
"That or it's fake.",
"[Here's a little documentary](_URL_0_) about him. He says he has been drinking from an early age and always had an unusually high tolerance, but still suffered some health problems resulting from at least one of his liquor chug videos.",
"I'm gonna take a crack at figuring out if that was a survivable dose, assuming he actually didn't throw it up after the video (which is more likely).\n\na lethal BAC is somewhere between 0.4% and 0.5% for a normal person. So lets figure out how many drinks it takes to get a person of Shoenice's build (approximately 200 lbs?) to lethal level. A man ShoeNice's size (200+ lbs.) should be able to consume something like 20 drinks (in a short period of time) before he's near the lethal range of BAC. \n\n\"1 drink\" is typically considered to be about 0.5 ounces of alcohol content in the drink. That bottle of everclear looks to be about 750 mls, which is about 25 ounces. If he drank the _ENTIRE_ bottle it would be like 50 drinks and he'd just die. He might have credibly chugged as much as 1/4 of the bottle and still had a chance to survive it. In the video he clearly chugged more than 1/4 of the bottle. It was not a survivable dose. He pretty much have to conclude that he threw it up immediately after drinking it. \n\n[source](_URL_0_)"
]
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3zx197 | Did a "closed state" like North Korea ever exist in pre-modern times? | I.e. a country where people were forced to have little to no interaction with the outside world in any form. Was this even possible before modern technology and Western-style bureaucracies? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3zx197/did_a_closed_state_like_north_korea_ever_exist_in/ | {
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"People are going to mention Joseon Korea and Tokugawa Japan. In fact, two people (/u/Shawn_Spenstar and /u/Das_Orakel_vom_Berge) have already:\n\n > This isnt my subject of expertise but it seems like Japan under the Tokugawa shogunate would have been pretty close to what you referring to. Their foreign policy of the time was one in which no foreigner could enter the country and no citizen could leave the country under penalty of death. However they did still trade with foreigners like the Dutch East India Company so it definitely not a perfect parallel.\n\nNow I am no expert on Tokugawa Japan, or any sort of Japan, either, but I do know Tokugawa Japan had extensive contacts with its various neighbors (besides the Dutch). \n\nIn Korea there was the Dongnae Japan House, a Japanese-inhabited outpost that was a locus of trade and interaction between the two countries. As a generalization, before the mid-18th century Korea sold ginseng and Chinese textiles and Japan sold silver, and after the mid-18th century Korea sold things like cow hide (as well as ginseng) and Japan began to sell copper a lot more. Things like samurai swords and Japanese maki spread among Koreans in the environs of the Japan House, and of course the Japanese islands of Tsushima, approximately between mainland Korea and the main islands of Japan, have many Korean cultural elements to this day. \n\nThe people of the tiny Kingdom of Ryukyu were thoroughly under the thumb of the Japanese, and of course there was trade between the Japanese and these southwestern cousins. The Ainu of the north were also increasingly falling under Japanese hegemony and rule, consequently with dramatic events such as Shakushain's War in the late 17th century.\n\nChina. Despite the idea that China and Japan were both secluded from the outside world, Qing China and Tokugawa Japan also had much trade going on between each other. I know really little about this trade (besides how it affected the Japan-Korea trade especially Korea's former position as middleman) but apparently a 1753 Chinese ship headed for Japan carried more than 12,000 books. So yeah, the trade wasn't tiny.\n\n > Korea was known as the Hermit Kingdom for a reason as well. North Korea currently conducts trade with several nations with its citizens themselves having little to no outside interaction, so Tokugawa Japan and Joeseon Korea are actually both very good parallels for what the question asks.\n\nThe Joseon government never in fact viewed itself as the head of an isolated state, so I always have the feeling that it's somewhat biased to call it a Hermit Kingdom and whatnot. Besides it's not necessarily true that the Joseon people had little to no outside interaction relative to other pre-modern, agricultural societies. From an elite perspective it's obviously not true, since there were annual missions to Beijing - more frequent missions than any other country was allowed. On a more private and mercantile level there was a lot of trade with China and rather less (but still more than a little) trade with Japan. Uiju, a fairly large town, appears to have depended almost entirely on the trade with China. The Japan House was probably a big part of the success of Dongnae. Sometimes Koreans were even allowed by Beijing to buy grain in the Jiangnan (the richest part of China).\n\n*The Northern Region of Korea: History, Identity, and Culture* has a chapter on how northern Korea was affected by the trade with China, and there's Schottenhaumer et al's *Trading Networks in Early Modern East Asia*. For Japan/Korea *Frontier Contact Between Choson Korea and Tokugawa Japan* is a case study of the Japan House and a good book, for the Ainu see *The Conquest of Ainu Lands: Ecology and Culture in Japanese Expansion, 1590-1800*, for the Ryukyus I found *Okinawa: The History of an Island People* pretty good. For the Sino-Japanese trade, sorry, I have nothing besides some information that accompanies the Japan-Korea trade. Also *To the Ends of Japan: Premodern Frontiers, Boundaries, and Interactions* might be helpful, but I have just read reviews of that one.\n"
]
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|
3eez0l | eye color | I am a white male with blue eyes, my GF is Mexican with brown eyes. What is the chance of us having a blue eyed baby? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eez0l/eli5_eye_color/ | {
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"Well, it isn't just a matter of what you and your partner have. There's a chance that there are some recessive genes that simply aren't showing up in either of you. To get a better idea of the actual chances you have to go back at least one generation to both of your parents. Here's a handy calculator that should help: _URL_0_",
"Since you have blue eyes, you likely only have genes for blue eyes. Blue eyes are recessive. In your girlfriend's case, though, it's conceivable that she may have one gene for brown eyes and another gene for a different color, but the other color is unexpressed, because recessive. However, if she has had no ancestors with anything but brown eyes, then it's probable that she has genes only for brown eyes. That means any child of yours would have a gene for brown eyes and a gene for blue eyes, making the child's eyes brown. But eye color is not a simple mendelian train. With a gene for brown eyes (that is, a gene that causes the production of a lot of pigment in the eyes) and a gene for blue eyes (a gene that causes the product of no pigment in the eyes), your child might end up with an eye color part way between blue and brown. That is, light brown or hazel."
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1r1n28 | what set apart google from yahoo, facebook from myspace (etc.) such that one failed where the other succeeded? | I remember a time when Myspace was big while Facebook was just coming up, a time when "Yahoo and Google" would be mentioned in the same sentence often enough. Yet now in hindsight, Google and Facebook clearly won out, while Yahoo/Myspace were to most either forgotten or relegated to uses secondary to their initial offering.
So, my question is: What did Google do right that Yahoo didn't do or did wrong? What key decisions let Facebook transcend the [network effect](_URL_0_) to eventually outpace Myspace? In short, **what key factors played a role in determining the outcome of these competitions?**
It can't just be that "they were the new thing," or else we'd see the same effects with G+ and basically any "next big social website" out there that got some views. What exactly set apart/determined which of a pack of sites is the last one standing? (I know Myspace and Yahoo are technically still around but they're basically non-existent now...) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r1n28/eli5_what_set_apart_google_from_yahoo_facebook/ | {
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"For me both were based on the lack of clutter. I never joined myspace because it was a cluster fuck and google was very simple and always gave me results without spamming the page full of non-sense. A lot of it has to do with how it was managed by the top level directors but for me this was a very important factor which I'm sure played a major role for others as well. Also, yahoo is FAR from extinct."
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pd5vk | What are the 'reset' and 'test' buttons for on a blowdryer? | I've only had to push reset a couple of times but I never knew what it actually did. | askscience | http://www.reddit.com/r/askscience/comments/pd5vk/what_are_the_reset_and_test_buttons_for_on_a/ | {
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"It's a built-in GFCI (_URL_0_). It's basically a sensitive circuit breaker to detect a short and kill power before you electrocute yourself."
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cjb2h9 | For how long after the Norman conquest of England can we find a distinction between Saxons and Normans | It is my understanding that even though the majority of the Saxon landed lords were deposed and replaced with Norman nobility, some did continue to hold lands and titles after William had consolidated his power. For how long did the distinction between a Saxon and a Norman last? During the House of Anjou period there was still a distinction between Saxon lords and Norman lords. Was the distinction felt until the Lancasters, or Tudors, or later?
An additional related question is: since the vast majority of the common folk residing within England were Saxon while the nobility was Norman and no nobility-changing invasions or major populations deplacements have taken place since the conquest, is it wrong to assume statistical significance in such traces even today. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/cjb2h9/for_how_long_after_the_norman_conquest_of_england/ | {
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"Follow up question: William the conqueror quickly distributed fiefs and lands to the Norman noblemen who followed him to England. For how long were these new landowners seen as intruding foreigners until they were accepted?",
"A previous thread had an answer that essentially said that there was no such thing as the Anglo-Saxon nobility within a relatively short timespan from 1066.\n\nThe response from /u/Vylander can be [found here](_URL_0_)."
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700u7m | how do manufacturers of vehicles make car keys that are unique such that not 1 car key is identical to the other? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/700u7m/eli5_how_do_manufacturers_of_vehicles_make_car/ | {
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"Certainly with normal keys, it's more than possible that there do exist keys that will open more than one lock, but the whole security of a lock and key is that you don't know that. \n\nOr put another way, if you were to find a random key at the side of the path one day and pick it up, would that make you any more likely, in the grand scheme of things, to be able to get into the house it came from? No, because you don't know which house that is. Could be any one of millions of keyholes. \n\nCars are the same. Odds are with the number of cars in the world, there are certainly keys that are duplicated somewhere, but how do you know where and what cars? You have no way of knowing. ",
"The trick is that they don't. They just need to make them unique enough that most keys do not fit. So there will be less accidents with people taking the wrong car and it is not convenient for car thieves to carry around a full set of keys. But that means that you might just need to make less then hundred unique keys for all the cars. Modern cars with radio chips in the key does have an added level of security as these often have a lot more unique patterns then physical keys.",
"If you're talking about physical keys, [they don't make them unique.](_URL_0_) They simply have enough different combinations that it is highly unlikely that you would ever find out if another car around you was using the same key. ",
"They don't.\n\nI distinctly remember someone talking of having a brand new car, going into the parking lot, blipping their car and an exact duplicate down to the colour and model responded.\n\nThe two drivers compared in amazement.\n\nI assume the manufacturers don't envisage it happening often enough to be a security risk.",
"One time my father and I got into the wrong car because he had this neon green Toyota I've never seen anyone else with. He was parked within the vicinity of the corner or the parking lot at our local mall-- we managed to notice within about 10 seconds that it didn't feel right.\n\nIt was a bit interesting for me since I was about 10 st the time!\n\nThere are definite key dupes ",
"Once upon a time I did accidentally open a car of the exact same make, model and color with the key to our family's car. It was in the parking lot of a mall and they were parked just a few cars away from ours. This was two decades ago before car remotes became popular.\n\nNowadays many manufacturers use laser cut keys which gives a pattern unique to each car, nearly eliminating the possibility of producing identical keys.",
"I worked at a local dealer for over 12 years and in that time twice we had to do a wärranty swap of ignitions. One a person either unlocked a matching vehicle at a mall parking lot and only realized as they went to back out and saw a kleenex box on the rear shelf. He left the owner a note explaining the event and later found out that he knew said owner. The second one was a buddy showing off his new car to the guy who bought one a few weeks earlier and for the hell of it they tried each others keys and yup they worked. Now these were both in the days before chipped ignition keys. It really is more common than one would think.",
"Certified Registered Locksmith of nearly 10 years here. Newer cars are getting better about this. Manufacturers are moving away from physical keys, to remotes and push to start systems. This is decreasing the likelihood that a random person will be able to accidentally access your car. \nFor older models that utilized pin tumblers that utilized cuts on the edge of the key as opposed to the face, it was common for manufacturers to only use a fraction of the key bitting for different locks on the car. The ignition would use the most, while the glove compartment might only use three, and the doors use five of a different combination, and the trunk will use a different combination of four or five as well. This worked because many keys had 8 cut positions. Ford, for example had 8 positions, with 4 different depths. This leads to nearly 65,000 different theoretical key combinations. Not all 65,000 could be used to to physical restrictions of the keys. It might not be possible for a deep cut next to a shallow cut on some manufacturers, or some manufacturers have specific rules about their key bittings. \nWith all that being said, car manufacturers do their best to make sure that you are the only person near you with a key to your car. But sometimes you may get an anomaly. But the likelihood of that happening is very small. Plus the transponder in the key is unique and must be programmed into the car. \n\nTldr: it is possible for cars to have keys, other than those with the car, to have identical cuts. However, vehicle manufacturers do what they can to limit this and electronic security is helping"
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s3ncx | If the nature of sexual attraction comes from natural selection and the desire to create healthy babies, why am I more attracted to a skinny woman than a muscly woman? | For example: I find this: _URL_0_
more attractive than this:_URL_1_
even though the latter is more likely to produce healthier, stronger, and genetically superior offspring than the former. | askscience | http://www.reddit.com/r/askscience/comments/s3ncx/if_the_nature_of_sexual_attraction_comes_from/ | {
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"May have to do with mating. Natural selection doesn't only evaluate for healthy children. A woman who has masculine features may have assumed a masculine role in society, and may be less capable of raising a family for those reasons. She may also be less submissive as those muscles could have developed from an excess of testosterone historically.\n\nSomething along those lines. ",
"There are two different questions you are asking. One is why you are more attracted to feminine looking women (without huge bulky muscles). The second, which is implied, is that the bulky muscle women are better suited to create healthy babies.\n\nThis second assumption is wrong. Women with large muscles often have higher testosterone levels. If those muscles are clearly defined, as in the picture you linked, they probably also have less fat. Both of those factors are actually less conducive to having a healthy baby.\n\nHigh testosterone causes fertility problems in women, as does having too little fat. The *type* of fat is also important. Men usually find fat around the hips to be more attractive than large bellies. It so happens that fat around the hips is rich in DHA, which is precisely the kind of fat that's needed to produce large-brained babies. Human babies have unusually large heads (and brains), and making such babies is much easier for women who have sufficient fat around their hips.\n\nSo by selecting for a woman with \"normal\" looking muscles and a larger hip-to-waist ratio, you are actually selecting for women who are more fertile and more capable of producing healthy babies.\n\nIt's important to remember that big muscles doesn't necessarily mean \"healthy\", biologically speaking. The woman in the first picture looks perfectly healthy to me. So long as the muscles are toned and used to activity, not flabby, it wouldn't make her any healthier if they were twice that size. Her hormonal levels are probably more conducive to keeping her heart healthier than the more muscular woman's. Again, those higher testosterone levels aren't very heart-healthy.\n\nThere is a normal variation among women, just as there is among men. There's nothing wrong with exercising, it does women good, just as it does men good. All women don't start with the same level of testosterone either. So there will be a range of body types and musculature. But if you pick the more extreme examples, such as women with very bulky muscles and low body fat, you will find that they probably started off with more testosterone to begin with, even if they take no hormone supplements to build those muscles. This can be good for bodybuilding competitions, but it's not a better body for producing healthy kids than a woman with smaller muscles and a more female-looking figure."
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1vkyc0 | does having more blades on a helicopter make a difference? | Title mostly says itself. So if one was to have 4 blades as opposed to 2 blades on a helicopter, would it make a difference?
EDIT: To clarify, I mean in terms of speed or height or other things | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1vkyc0/eli5_does_having_more_blades_on_a_helicopter_make/ | {
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"It would make a difference. But what difference? That extremely complex to answer.\n\nMore blades would be capable of lifting more weight.\n\nBut after that, you need to know the exact details of the blades and the helicopters to know what effect it will have. It will almost certainly affect the noise of the helicopter. It will affect its empty weight, and, because of that, perhaps its handling characteristics. You might also find that each blade gets caught in the down wash from the previous blade, which will alter how effective each blade is. It will also increase manufacturing and maintenance costs.\n\nYou can be pretty sure, though, that the designer has taken into account the intended usage of the helicopter and designed it with the number of blades which is the best compromise for the job it's going to do.",
"Each blade generates lift proportional to its area and the rpm it's spun at, right?\n\nSo, take two hypothetical copters with blades of equal length, but one has four blades and the other has two? Four blades should generate a good deal more lift, but very likely less than twice as much. Fluids get turbulent; turbulence eats efficiency.\n\nPushing the blades through air creates resistance. This requires horsepower to overcome, so the four-bladed copter will require a more powerful engine to spin its rotor at the same rate. It probably requires slightly more than twice as much power to spin four blades as it does two, not to mention that now you have to lift a heavier engine.\n\nSo copter designers must find optimal \"sweet spots\" in compromising between number of blades, power (and thus weight & bulk) of engine, and other attributes of the craft. Most are designed with pretty specific functions in mind, so it might help you to read up on for example the difference between a cargo moving helicopter and one intended for anti-tank combat. They're both technically helicopters, but with completely different design priorities.\n\nForm follows function. Engineers are some clever people.\n",
"The speed limit of a chopper is directly affected by the maximum speed of the tip of the rotor on the forward moving side. If its speed relative to the air approaches supersonic speed you'll get nasty aerodynamics, so you can't get above that.\n\nAn increased number of rotor blades has improved lift compared to a rotor with less blades that is otherwise identical, but also uses proportionally more power (is less efficient)\n\nTherefore you can achieve the same lift at lower RPM or more lift at the same, allowing you to increase the speed limit or maximum weight while maintaining the same speed at the cost of efficiency\n\nIncreasing rotor diameter has similar effects minus the hit in efficiency, but of course there is a limit to how much you can increase the rotor diameter, and it may affect handling in a negative way\n\nedit: Grammar\n",
"Generally, if we assume the helicopter has the same amount of power, rotor shaft rpm, weight etc and you only change the number of blades and the rotor diameter;\n\nHaving more blades allows you to use a smaller diameter rotor to get the same lift, which means the tip speed is reduced, and the helicopter can fly faster. If you wanted to lift a large payload with only two blades you could either use a very large diameter rotor or spin the blades faster. Both of these options will mean the blade tips will be approaching or higher than supersonic airspeeds, which can be cause catastrophic vibrations and buffeting. It also limits the top speeds, because even if the blades aren't already transonic, as soon as you have any forward speed, the proceeding blade will go transonic.\n\nGenerally no more than 5 or 6 blades are used on the same rotor, because more blades results in less efficiency. This is due to the following blades flying through the previous blades wake. Once you go above a certain number of blades (I don't know exactly, because it probably changes for different helicopters) the added lift is negated by the reduced efficiency of all the blade.\n\nFor altitude you want as much lift as possible and to get that out of the same amount of power you want the most efficient blade configuration, which is usually the lowest number of blades you can get away with. But helicopters normally don't even have pressurized cabins, so you fly up until the pilot passes out.\n\ntl;dr: More blades allow for higher speeds up to a point were the reduction in efficiency results in minimal advantage."
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5zkayt | why is heaven most commonly referred to as being up above the earth while hell is most commonly referred to as being down below the earth or in the ground? when did this tradition come about? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5zkayt/eli5_why_is_heaven_most_commonly_referred_to_as/ | {
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"It's really old. The ancient Egyptians had this notion, 5000 years ago. The Jews, and then the Christians, and then Dante colorized them as we think about them today, but the idea goes way back.",
"Many early religions and the basis of modern religion appears to be based upon worship of the sun. The sun of course is in the sky and appears to go away \"into the ground\" as the sun sets. Celebrations centering around the solstices or lunar cycles highlight this relationship to celestial bodies.",
"There is a certain logic to the heavens being above us. The Greeks reasoned that the heavens were very different from the Earth, being ordered and not subject to decay. It was thought that the heavens were composed of an entirely different type of matter (aether) than the four elements that made up the Earth.\n\nAstronomical observations eventually disproved this view, Newton showed that the law of gravity explained the orbits of the planets and other solar system bodies, and spectroscopy proved that stars were composed of the same elements as found on Earth. Also, that our Universe is in a constant state of change and evolution, but on its own rather than a human timescale.",
"It's because of the stories of the Bible. In the Bible it states that God created a vault to separate waters from waters (ocean from weather) and that God looks down upon us from far above, above another vault separating sky from heaven (this vault is space)"
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22rhwz | given that life has existed far longer in our oceans than on land, why hasn't there been species that evolved with the same intelligence level has higher primates? | An earlier question concluded that dolphins are an example of an aquatic intelligent species and yet humans have been far more successful. This also doesn't account for the fact that life existed in our oceans far, far longer than it has on land.
Basically, I want to know why we aren't having epic battles with mermen for rule over Earth. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22rhwz/eli5_given_that_life_has_existed_far_longer_in/ | {
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"Human-style intelligence, while very cool, is not easy to evolve, and it is not free. It requires a lot of energy to run our brain, for example, and in an environment without fire, and where communication is harder, that cost may not be worth it, at least at the intermediate stages between, say, a proto-lemur and a person. Similarly a lot of what allows us to be truly dominant over the planet is relatively recent. In a world without easily accessible coal deposits, or more difficult to domesticate animals, or any of a number of other things our population would be a lot smaller and less technologically advanced, and we probably would still be fighting bears and mammoths for rule over Earth. Note that dinosaurs ruled the earth for 165 million years, and as far as we know, there wasn't a one of them that had human like intelligence. And if they did, they certainly never ended up with a recognizable, technology driven society. \n\nAlso, the particular path many think led to the development of human intelligence would also be difficult to replicate in the sea. Language was a big driver of the development of our brains, and that's hard to get. We also split off from true sea creatures (like fish, rather than dolphins and other sea mammals) very early, so the structure of the brain is very, very different. Squid and Octopi are very intelligent, but their basic brain structure is distributed, and may not be capable of becoming \"human-like.\" That's not to say they couldn't be smart, or better at some kinds of \"thinking\" just that it would be very alien and might not lead to the kind of society that has allowed homo sapien to extend a technological and social dominion over the planet. ",
"Evolution doesn't have a specific goal.\n\nIt isn't like \"Human Level Intelligence\" is the goal that everything is working towards.\n\nEverything adapts in such a way as to be specialized for the environment in which it lives; those which are better adapted to the environment tend to live, while those which are less adapted tend to die.\n\nHumans became so intelligent because of a couple of specific mutations in specific genes; one of the big ones was in a gene that codes for our jaw strength, oddly enough.\n\nThat gene ALSO codes for brain size; so as our jaws grew weaker, our brains grew larger and more complex, and the increased intelligence gave a greater adaptability to our environment than the reduced jaw size removed.",
"you mean dolphins?",
"To thrive and survive in that environment has and does something different than it does topside. I guess you would call it incidental but our evolutionary process required a lot of tactile desterity which brought us to a point where we became tool users, which ultimately led us to where we are now. Such is not the case in the ocean environment.",
"Traits are not evolved just through time, they are evolved because they make the organism life significantly longer. \n\nThe most likely reason for man's evolution, beside just dumb luck, is that surface life is more complex due to more rapidly changing environmental factors and higher availability of resources. \n\nOne of the best ways to spur evolution is by killing off mass amounts of creatures including the organism you want to evolve and/or it's competitors. \n\nThe easiest way to think about evolution is in terms of bacteria. If we wanted to force bacteria to evolve how could we do it? We could overuse antibiotics, killing off bacteria and creating a strong stimulus for natural selection to favor a mutation. We could change the environment which impacts untold amounts of variables, particularly increasing heat or fuels (like animal waste) for bacteria to breed.\n\nThe oceans are so large and don't really have weather and seasons like the surface of the earth. That makes them more resistant to rapid change. As a consequence most marine life cannot take rapid change nearly as well as surface life. The average lifespan of a dolphin is an amazing 40-50 years, while the average lifespan of primitive man is estimated to be about 23. Life on the surface is harder for most creatures and that leads to a faster life cycle and better chances of evolving since evolution only happens via reproduction. This is again by bacteria or things like fruit flies are great ways to study evolution.\n\nEvents like the meteor strike that killed off a huge percentage of life on the planet are huge catalysts for evolution but they tend to impact the surface animals more rapidly. Things like changing seasons are also constant motivators of evolution since they provide a rather consistent challenge to life.\n\nIf organisms have few challenges they will not evolve as quickly because mutations will not increase their lifespans as significantly, thus instead of a new mutation sweeping over the population due to it being an overwhelming advantage, the mutation will not spread as rapidly and could even die off due to lack of being passed on enough. \n\nEvolution and intelligence really don't have all that much to do with time. Life existed on earth for billions of years and anything resembling man has only existed for a few million.\n\nSo, the main lesson here is to not associate time with the development of intelligence. Intelligence is most likely developed by some really lucky mutations and environmental conditions that lead to the rapid adoption of those genetics into the species, thus ensuring that train takes hold as a new feature of the species. \n\nSo the real question is.. what the hell happened to primates a couple million years ago that so rapidly led to humanity. ",
"Because evolution doesn't give a crap about what we think is better or worse :D\nA cave dwelling fish is doing pretty well by having no eyes.\nWhat I mean is, evolution is not about getting better, bigger, stronger, it's just about survival... (actually its more about sex).",
"Since inate \"intelligence\" isn't really quantifiable, who is to say there are not similarly elevated levels, even though they can't be observed by human standards? After all, fossilized evidence of examples of man's intelligence didn't come to be until after we'd evolved, not a bigger brain, but opposable thumbs.",
"I know this is a highly debated subject, but the consensus seems to be that cuttlefish octopuses etc are intelligent.\n\n_URL_1_\n\nAnd that's not even taking aquatic mammals into account.\n\n_URL_0_"
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8u2asp | What was the highest number of Frenchmen to ever live in French Algeria? With said territory being considered an integral part of France, how realistic would it be for French Algeria to remain a part of France? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8u2asp/what_was_the_highest_number_of_frenchmen_to_ever/ | {
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"Hey!\n\nUnfortunately, we've had to remove your question--\"how realistic would it have been\" demands a speculative answer, which doesn't work. **However**, you have a real question here! Could you please resubmit it as \"How many native French people were in French Algeria? If it was so integrated into France, why did Algeria seek independence?\" or something else concrete along those lines. (That is, ask \"why did\" instead of \"how could it have been different.\"\n\nThanks!"
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2uy7xs | Everything in space orbits something, right? | OK, so let's see if I can get this right. The Moon orbits the Earth, the Earth orbits The Sun, The Sun orbits the center of the Milky Way, the Milky Way orbits the center of the Virgo Supercluster, but what does the Virgo Supercluster orbit? Is there just some massive object out there in space and we don't know what it is? What could possibly be bigger than a Supercluster? And whatever it is, does it orbit around something as well? Is there just an infinite loop of something orbiting something else? I get that space is ever expanding, but wouldn't it have to stop somewhere? So when it does, how massive could that largest object POSSIBLY be?
And now for the biggest question (lol), putting space and it's size into a perspective like this, why is it seen as insane to think that there is life out there somewhere? (inb4 crazy ufo people and little green men) | askscience | http://www.reddit.com/r/askscience/comments/2uy7xs/everything_in_space_orbits_something_right/ | {
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"No, not everything orbits something else. The largest orbits in the universe are those of galaxies within galaxy clusters, but those take such a long time (billions of years) that they aren't consistent or stable. At the supercluster scale, things stop being gravitationally bound to each other. We're not bound to the Virgo Supercluster, and we aren't orbiting it. On very large scales, the universe is **not** rotating, and the peculiar motion of galaxies is insignificant compared to the spreading out of the universe, which precludes large-scale orbits.\n\nMost astronomers think it's quite likely that there is other life in the universe. One of the fundamental ideas underlying modern astronomy is the Copernican Principle, which could be summarized as \"We are not special\". The last half millennium of astronomy has been a continuous fight against the idea that we occupy a privileged place in the universe. The discovery over the past several years that planets are extremely commonplace only further supports the idea that life probably exists other places besides Earth.",
"If you want to get technical nothing is orbiting \"something\" but instead each of those things is orbiting a point in space between them. \n\nFor example, Jupiter doesnt orbit around the Sun. Both Jupiter and the Sun orbit around the location of their combined center of mass. I use this example because that point is actually [outside of the sun itself] (_URL_0_), albeit very close to the surface. The Earth and the Sun both orbit a similar point, but in this case the point is inside the Sun and close to the center. So most people and applications will ignore this and say that the Earth is orbiting the Sun, which is pretty accurate. \n\nThe only reason I point this out to people is because it can lead to misconceptions and questions like can a star orbit another star. No, they orbit a point between them that is determined by the ratio of their masses. Same goes for everything. \n\nFor the non-pedantic answer that actually answers what you were asking see Das_mines answer."
]
} | [] | [] | [
[],
[
"https://en.wikipedia.org/wiki/Jupiter#Orbit_and_rotation"
]
] |
|
29f2o5 | The last caliphate ended with the Ottoman Empire in the 1920s. Why has it taken until 2014 for the Muslim world to declare a new one? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/29f2o5/the_last_caliphate_ended_with_the_ottoman_empire/ | {
"a_id": [
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"score": [
26,
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"text": [
"It should be pointed out that this is a unilateral declaration by a group seeking greater cachet among fervent [Sunni] believers, not a declaration by \"the Muslim world\" as a whole. If you do not control the Holy Places, you can't make much of a claim to Caliphate in the broadest sense; if you are a tiny fraction of the world's Muslims, even less so. There was not, and is not, a single predominant Islamic power that could reliably make the claim to true succession from the Prophet and have it taken seriously. The Ottomans, on the other hand, controlled an enormous percentage of the Islamic world in the 16th and 17th centuries, which is why they could take it on--but whether the Ottoman claim ever carried the weight it had for earlier Caliphates is doubtful.\n\n[edit: As a follow-on question for the Islamic 20th-C. specialists, is this the first time a group or entity has sought to proclaim that connection? I'm not aware of the Saudis ever trying, and I can't imagine they would be happy about anyone else doing it either.]",
"Additional question: has anybody ever seriously floated the idea of having a caliph, but having him be more like the equivalent of a pope, with no real power, but acting as a spiritual leader?"
]
} | [] | [] | [
[],
[]
] |
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