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2awwxi
|
why do humans have such small irises compared to other animals?
|
I've always wondered this. I can't see the whites of my dogs' eyes unless they're looking to the side. I can hardly see the whites of a cats' eyes at all. Why are humans different?
I mean, I think we would look terrifying with huge irises, but still.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2awwxi/eli5_why_do_humans_have_such_small_irises/
|
{
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"cizljhe"
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"text": [
"There are a few ideas, one being the \"cooperative eye hypothesis\" which suggests that it is easier to follow another's gaze when communicating. We communicate a lot through our eye gaze, and it's easier to distinguish different communicative attempts from one another with the white part (sclera) present. Another idea suggests it's a sign of good health when choosing a partner. "
]
}
|
[] |
[] |
[
[]
] |
|
np8dp
|
would it be legal at all for godaddy to be specifically exempt from the sopa legislation? if not... how was that clause worked in?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/np8dp/eli5_would_it_be_legal_at_all_for_godaddy_to_be/
|
{
"a_id": [
"c3auphc",
"c3auphc"
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3
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"text": [
"When you make the law, you can make anything you want legal. GoDaddy will probably just become a branch of the government, the one that controls domain name.\n\nIt's not like there was something governing what power the state should have over the citizen or how it should behave. \n\nMaybe we should have something like that and call it the constitution, it would help a lot these days. ",
"When you make the law, you can make anything you want legal. GoDaddy will probably just become a branch of the government, the one that controls domain name.\n\nIt's not like there was something governing what power the state should have over the citizen or how it should behave. \n\nMaybe we should have something like that and call it the constitution, it would help a lot these days. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
3t10gf
|
when software updates say they've optimised it to run faster, what exactly did they do and why didn't they do it before?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3t10gf/eli5_when_software_updates_say_theyve_optimised/
|
{
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"cx245v1"
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"text": [
"Let's say you have an old PC game. The game is written to run on Windows 2000, but it still works on Windows 7. Sort of.\n\nWell that company might re-release the game *Optimized for Windows 7*.\n\nThey physically re-work the code of the program so it works better with the current system. \n\n____\n\nOther programs may have already been written for that current system, but those systems can go through updates too that might conflict with the program. This would cause the software to need an update so it can run without issues on the updated software."
]
}
|
[] |
[] |
[
[]
] |
||
1s1jpn
|
when a large company (typically oil & tobacco) has "lobbyists in washington" how does that actually affect the passing of legislation?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s1jpn/eli5_when_a_large_company_typically_oil_tobacco/
|
{
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"You know how when you want a family portrait *painted* you go to that person with the little cart in your local shopping mall, who has been there since before you were born, and you give that person a commission fee and they paint you a stunning portrait of your family?\n\nA lobbyist is the same thing. They do something for a fee—in this case—they perform civic duties that all citizens can perform. They petition, meet, rally, network, collaborate and organize to pass something through congress.\n\nSo what's with my painting example? Because everyone has the potential to be a painter, but some people are *paid* to paint. A lobbyist is the same thing. A lobbyist is paid to move something through legislation.\n\nAs to the very specific *how*: through all the legal channels, but primarily, by establishing relationships. So lobbyists are kinda like high school popular kids in that respect.\n\nBut there's another big component: lobbyists are researchers too. They know *everything* they can about the issue and make decisions about how to spin things, sell things, and frame things. It's like a chess match meets a high school science fair meets a ad agency.\n\nSource: some good friends in the lobbying biz. I gladly welcome revisions from anyone with corrections as I could be off.",
"The vast, vast majority of legislation out there isn't something the public pays attention to. It's stuff like changing regulations on oil refinement, or making new tariffs on trade in a specific industry. Lawmakers, especially in the House, are constantly campaigning, so they need money. So, if you're willing to give them the benefit of the doubt, they use lobbyists to help them wrap their heads around complex legislation on a subject they've never learned about before. Since a law will have winners, losers, and thus opposing lobbyists, the dueling lobbyists can each plead his case and the lawmaker can make an informed choice. If you're skeptical, they sell their votes for campaign money, especially in the cases where the voting public doesn't really care, and thus neither side of the vote will win them reelection.",
"Lobbying is essentially just meeting with congressmen.\n\nWhat is means when you hear \"such and such company has lobbyists in Washington\" it means that they pay people to be active in meeting with congressmen and talking about what the company wants.\n\nThe reason lobbyists have so much influence is two things:\n\nA. Lobbyists actually talk to and communicate with congressmen. This goes a long way to shaping their opinions. Just knowing about legislation that's seen as important can make them look into things deeper or vote with what seems to be the choice people want.\n\nB. Companies give large donations to political campaigns. Congressmen know that, so when they hear \"Hey Wal-Mart wants you to sponser bill ABC\" they know that might also mean \"Wal-Mart is willing to donate money towards politicians who sponser bill ABC.\"\n\nMoney is extremely important and influencial for political campaigns, and so when they're asked to support a bill and know that money is on the line, they're a lot more likely to support that bill. \n\n____\n\nFor example, consider that you're the senator from some state, and drilling for oil is the big issue that's dividing people left and right. You want to take a stance so that you can seem confident when you go up for re-election in a year.\n\nIf the only people you hear from are big oil companies who are completely for drilling and donate big bucks to pro-oil candidates, there is a strong likelyhood that you will lean towards drilling. All other things being equal, being pro-drilling gives you the backing of Big Oil and their donations. \n\nSimilarly, if you hear from members of your state and Anti-Drilling groups, you're much likelier to be against drilling.\n\n____\n\nAnother example: Consider again your a Senator. You go about your business, and a law comes up in discussion some time. It's some tobacco regulation. It doesn't seem very important, and you don't pay it much mind. You might vote on it but you might just abstain.\n\nLater that week, however, one of the people who meets with you happens to be a lobbyist for a tobacco company. He asks you to vote against the regulation, as it's a very important issue for the companies he represents.\n\nAt this point, you decide to vote against the regulation. You weren't really considering it very much beforehand, but now you have a specific reason to vote on the issue. Not only do you make members of your state happy, but you gain favor from tobacco companies who you can likely rely on for donations in the future. \n\n____\n\nReally, the core of lobbying is that congressmen want to be reelected. Votes are the most important thing to them, and lobbying tells them what will give them votes. Whether it's having people support you with votes directly or with donations, hearing from lobbyists helps them know what legislation to back in order to get votes."
]
}
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[] |
[
[],
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||
16bl2d
|
Non-American scholars of US History: What inspired you start?
|
As an American, I think it is very interesting that anyone would want to focus learning about the US. While interested in history in general, I never particularly enjoyed learning about US history, so I was curious to hear what others found appealing about the history of the country.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/16bl2d/nonamerican_scholars_of_us_history_what_inspired/
|
{
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"c7uiw4h"
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"I'm not completely US-oriented since I'm interested in the 19th century in general and not just the US, but I did take a lot of classes on US history and I was always fascinated by how much the US considered themselves special, from the puritans' concept of \"city on a hill\" to Manifest Destiny.\n\nAlso, I like how you can see the US's various historical border changes by looking at your states' borders. It's like living history."
]
}
|
[] |
[] |
[
[]
] |
|
alkdxp
|
What would happen to a single photon going through a prism?
|
To clarify things, let's make the prism "perfect" in the sense that it has no imperfections.
Furthermore, let's make it a photon of "red" light (625 - 740nm).
Here's one rough explanation of what happens:
If one were to conduct the experiment with a beam of red light, an angle of refraction would be observed. This angle of refraction would of course, be less than that if one were to employ a beam of "violet" light.
Now repeat with a single photon of "red" light: If the photon is not observed until after passing through the prism, it is fair to say that it should have passed through the prism as would a wave with the wavelength of red light. On the other side of the prism, it will be detected with an angle of refraction corresponding to "red" light.
Any thoughts on the above?
This has been asked before, but I felt the responses were not as clear they could have been, perhaps because the question & main assumptions required clarification:
[_URL_0_](_URL_1_)
|
askscience
|
https://www.reddit.com/r/askscience/comments/alkdxp/what_would_happen_to_a_single_photon_going/
|
{
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"text": [
"Describing the statistics of photons passing through a prism, as though a classical electromagnetic wave were passing through it, and where this classical EM wave determines the photon statistics is a perfectly legitimate way to go. The quantum operators for the electric and magnetic field actually obey Maxwell's equations, just like in classical Electromagnetism.\n\n & #x200B;\n\nIn quantum optics, describing a single photon passing through a prism would be:\n\nFirst: Give the initial quantum state of the electromagnetic field\n\nHere, it's a single -photon state with a given frequency spectrum and momentum.\n\nSecond: Propagate the initial state of the field to the final state of the field using Maxwell's equations for the operators, or Heisenberg's equations of motion.\n\nThird: Calculate the statistics of the final state of the field\n\nHere it would be a single-photon state whose momentum is now correlated to its frequency spectrum due to the prism."
]
}
|
[] |
[
"https://www.reddit.com/r/askscience/comments/22icbf/what\\_happens\\_to\\_an\\_individual\\_photon\\_when/",
"https://www.reddit.com/r/askscience/comments/22icbf/what_happens_to_an_individual_photon_when/"
] |
[
[]
] |
|
2yj055
|
why are white paints always bluish in color?
|
How does adding blue tint to a white paint make it more "white"? I hate the painter who always adds some violet pigment to white paint. He says it makes it more white. Sounds like an absolute BS to me, as I can see he turned the paint bluish and left me wanting for pure white.
But just yesterday I purchased a 100mL synthetic enamel for painting my bicycle. It said "Brill White" on the top, and I was too happy that I finally got industry standard "white", and no more bluish crap. But I was appalled to find the "Brill White" had a tint of blue in it too and was not pure white!
What the hell is going on?
**EDIT:** [This](_URL_0_) is what I mean; bluish "white" paint on a sheet of "white" paper.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2yj055/eli5_why_are_white_paints_always_bluish_in_color/
|
{
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"text": [
"There are lots of colors of white. It sounds like you are looking at \"cool whites,\" but there are also \"warm whites\" which use yellow or other warm colors as a slight tint.",
"blue tint is added to white fabric to make it appear whiter. the blue tint cuts the yellow."
]
}
|
[] |
[
"http://imgur.com/wk3Ffdt"
] |
[
[],
[]
] |
|
fngfw5
|
why it is hard to think about death deeply?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fngfw5/eli5_why_it_is_hard_to_think_about_death_deeply/
|
{
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"fl9gd32",
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"text": [
"Imagination doesn’t actually ever create truly new things. It takes bits and pieces of experiences that you’ve had and uses those to construct what you’re imagining.\n\nIf you want to test this, try imagining a colour you’ve never seen.\n\nThinking deeply about death falls into the realm of trying to imagine something you’ve never experienced. You’re alive and as far as your brain is concerned always have been. So to imagine death it has no construct to piece together what it is like. The brain can fritz out while attempting to do this as it’s searching hard through your memories for something related.\n\nThis may cause the fear response you feel especially since we are told enough messages that death is something to fear.",
"Maybe you haven't accept it I know when I was a kid I would cry thinking about it I was also 10 probably"
]
}
|
[] |
[] |
[
[],
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||
a3o81v
|
genome vs. gene expression
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a3o81v/eli5_genome_vs_gene_expression/
|
{
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"text": [
"Genome are all of your genes in your DNA.\n\nGene expression is wheter or not a gene is expressed.\n\nWe, human, have lots of DNA but only a minority of it is expressed, it's called \"coding DNA\" , the non expressed part of our DNA is very much studied now because we realised how important it could be in terms of regulation of the coding DNA and its implication in diseases.\n\nAnd lots of things affect expression, like non-coding DNA seems to regulate coding DNA. \n\n & #x200B;",
"Your genome is all the DNA that defines how your body operates. It's the same in all the cells in your body (except for sperm/egg cells - they have half your genome).\n\nGene expression defines what kind of cell each one is. So a skin cell and a muscle cell have different gene expression patterns.\n\nGene expression regulation is *incredibly* complicated, but the most basic principle is described by the central dogma of biology. DNA is transcribed to RNA and RNA is translated to proteins. Proteins do most of the work in a cell, including transcription and translation. They also regulate transcription and translation.\n\nTo define where a transcription starts and ends, the DNA has specific codes that are recognized by a protein RNA polymerase which starts making an RNA version of the gene. The binding of the RNA polymerase is regulated by other proteins called transcription factors. These can be regulated by chemicals, hormones etc. Transcription factors enhance or decrease the ability of the RNA polymerase to make mRNA.\n\nThe way the DNA is structured also determines what genes are expressed. The DNA strands are wound around histones. The histones are grouped in such a way that some DNA is accessible, while other DNA is blocked in. Different types of histones have different configurations, and so they affect which genes are expressed.\n\nOnce the mRNA is made, it can be translated into proteins, but again there are mechanisms that affect this. Some non-coding RNA is made by the RNA polymerase, and these can trigger degradation of mRNA to further regulate which proteins are ultimately produced by the cell.\n\nSo to summarize, expression is affected by the cell type and signals from inside and outside the cells (chemicals, sugars, hormones etc.). The regulation uses structure (histones etc.), protein signals (transcription factors etc.) and RNA signals to determine which genes are expressed (meaning which proteins are made)."
]
}
|
[] |
[] |
[
[],
[]
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|
46jgmu
|
Let's just say that the LHC had a place that you could open up and get inside the collider. What would happen if particles were accelerated to maximum speed and you stepped in front of them?
|
askscience
|
https://www.reddit.com/r/askscience/comments/46jgmu/lets_just_say_that_the_lhc_had_a_place_that_you/
|
{
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"text": [
"[Nothing good](_URL_0_). A single beam in the LHC is about 100 times as powerful as the beam that Bugorski encountered. Even if the beam struck somewhere other than your head, the local nerves would probably be permanently damaged."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Anatoli_Bugorski"
]
] |
||
4ajfbp
|
What would be the biggest boat I could build if I was a king or a rich person around 1000 CE in western Europe?
|
I mean of course a boat that would float and be able to reach a destination even if it is slow and hard to control. I understand having a fleet of smaller boats is way better, but I'm thinking about size only here (lenght, width, carrying capacity).
If the biggest possible boat was not in western Europe, I'm interested as well to know where it would be.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4ajfbp/what_would_be_the_biggest_boat_i_could_build_if_i/
|
{
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"It's hard to say with confidence how big of a boat *could* have been built at that time. A lot depends on the design and the resources said king could have pulled together. At the time a large cog would be about 50 or 60 feet in length, and carry maybe up to 150 tons. Supposedly, there were some legendary viking longships that were up to 150 feet long, though those are not that well documented as far as I know.\nTry checking out: Gillian Hutchinson, *Medieval Ships and Shipping*\n\nDisclaimer: I'm not a Medieval naval expert, though I do have some history in Medieval Mediterranean trade. If anyone has better information than I, please correct me.",
"Others will be able to answer this much better but without being able to speak for the other parts of the world, in China this was one of the golden ages of ship building.\n\n[The Quanzhou junk](_URL_0_) for example was an unearthed wrecked Junk from Song Dynasty (though slightly later than 1000 CE) with three masts and was over 114 ft. in length - meant to be about average size of sea-faring junks in the era. There were probably much larger ships as even 1000 years before this in the Han Dynasty four to seven mast junks were described by court historians. Joseph Needham in \"Science and Civilization in China\" describes that there were allegedly 12 mast junks in that era in the Song Dynasty, capable of carrying 1000 men each."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Quanzhou_ship"
]
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|
753euw
|
For how long has October/Halloween/All Hallows' Eve been associated with spooky, mystical forces and the dead?
|
Could it be that this holiday and traditions associated with it reflect a vestige of a mindset from an earlier age where goblins, ghosts, witches, demons and faeries were thought to be real and lurking in the dark corners of the world at any time of year?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/753euw/for_how_long_has_octoberhalloweenall_hallows_eve/
|
{
"a_id": [
"do3cb0d"
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"text": [
"The simple answer to your second question is yes, the modern Halloween associations with supernatural entities reflects 'a mindset from an earlier age' when these things were 'thought to be real and lurking in the dark corners of the world at any time of the year'. It also appears that the end of October/beginning of November has a long specific association with these 'spooky, mystical forces and the dead'.\n\nThe problem with arriving at a definitive answer to your questions is that primary sources are not always precise about these sorts of things, and there needs to be a lot of inferences - a lot of connecting the dots with too few dots. There is a sufficient body of information to indicate that in Britain and Ireland there was a strong association of this time of year with the opening of a door between the natural and the supernatural worlds, allowing for crossing over and contact with powerful forces. In Irish Gaelic, it is called Samhain, and ethnographic/folklore work gives clear evidence to this being an important part of the Irish calendar. In addition, references in primary sources hint at the antiquity of this calendar tradition; it is likely a tradition that predates historical records associated with conversion to Christianity.\n\nA great deal has been written on this; an excellent summary of these calendar traditions appears in James MacKillop, A Dictionary of Celtic Mythology (Oxford: Oxford University Press, 1998)."
]
}
|
[] |
[] |
[
[]
] |
|
7qxy92
|
why is it that certain weapons, like poisonous gasses, are banned from use in warfare by the geneva convention, yet countries and governments can still use them against their own population, such as tear gas to control riots?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7qxy92/eli5_why_is_it_that_certain_weapons_like/
|
{
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"Geneva convention is largely a gentlemen agreement. No one wants their soldiers getting gassed or having to patch up wounds from hollow points. Its easier to just say no one gets chemical weapons and fight with conventional weapons, then it is to say \"there are no rules\" and everyone have them. Its already illegal for citizens to use tear gas on cops, so there is no objective reason to outlaw it for law enforcement.\n\nThe question of its something is humane or not doesnt really tend to stand in the way of most governments. ",
"The Geneva conventions mostly specifically relate to wartime activity and uniformed combatants.\n\nRioters are neither at war nor uniformed combatants, and therefore only subject to local laws.\n\nIf the international community deems the local laws too harsh they may individually or collectively take action, but historically nations have been allowed to do pretty much anything to their own populace.\n",
"Weapons are banned in war because governments think it'll piss off other governments if they use it so they don't. They're allowed to exist, but if you drop nerve gas on enemy combatants you can bet you're going to have it dropped on one of your cities too.\n\nOne interesting case that gives some context to this is the ban on exploding bullets. In 1863 Russia developed a musketball that could light hard targets on fire, in 1867 they developed an explosive musketball that would explode on impact even with soft targets. They knew this would trigger an arms race as their neighbors worked to create their own explosive musketballs and it would be awful for both sides. To avoid this, they called a convention in Saint Petersburg in 1868 and issued the [Saint Petersburg Declaration of 1868](_URL_0_) which banned the use of explosive bullets, but not artillery shells because they're more likely to kill and not maim. Thus, their fear of having their new weapon used against them led to them getting everyone to ban it instead."
]
}
|
[] |
[] |
[
[],
[],
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"https://en.wikipedia.org/wiki/Saint_Petersburg_Declaration_of_1868"
]
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||
to8bm
|
Why do humans make similar facial expressions in response to similar situations? Nature, or nurture?
|
Is this because we have these facial expressions encoded into our DNA as reactions to certain stimuli, or is it just a social reaction that we are all just taught at a young age? Basically my thought is if we were to do the classic experiment of taking 100 children at birth and isolating them from the world with little to no foreign influence, would they have the same facial expressions for the same emotions, or would they develop new ones that became the norm?
|
askscience
|
http://www.reddit.com/r/askscience/comments/to8bm/why_do_humans_make_similar_facial_expressions_in/
|
{
"a_id": [
"c4occpb"
],
"score": [
2
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"text": [
"I would say the basic facial expression are a product of nature and cite the work of [Paul Ekman](_URL_0_).\n\nBTW, the TV show Lie to Me was inspired by his work on facial expressions and lying. However, the early work on basic human emotions and facial expressions pre-dated the lying work. \n\n\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Paul_Ekman"
]
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|
4wpz5c
|
whats the difference between christianity and orthodox christianity?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4wpz5c/eli5whats_the_difference_between_christianity_and/
|
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"text": [
"Well, since you are asking this question, I assume you know what Catholicism is. With the Pope and the Vatican and the Baby Jesus.\n\nEastern Orthodox Christianity is essentially a different group of Christians, who believe they are the One, Holy, Catholic and Apostolic Church, that was established by Jesus Christ.\n\nBasically, very early on in the history of the Christian church, there were some philosophical disagreements between very highly ranked members of the Christian Church, things like \"Is the Holy Trinity three distinct entities, or are they all aspect of one.\", \"Is the nature of Christ one of man, or one divine, a mixture of both, or is he both at once.\" and other various things. These people disagreed, and they had a falling out.\n\nSo they are Christians, technically, who don't follow the standard ideas of Catholicism, which is the more common form of Christianity. They don't believe the pope is the representation of god's will on earth and they have their own leadership and ideas on the nature of man, god, and the relationship between the two.\n\nI hope that answers your question, they are a subdivision of Christianity, in a similar sense to Protestants or Baptists, but the split became much earlier, and they are, as such, a bit different to most other groups of christianity.",
"The meaning of \"Orthodox\" in the Christian teaching is to denote a kind of Christianity that, according to the speaker, is close to the early Christian beliefs. This means that many different branches of Christianity are likely to regard themselves as orthodox, even if they are at odds with each other regarding theological matters.\n\n\"Orthodox Christianity\" is often used to refer to the Eastern Orthodox Church, which is one of the branches of Christianity, one that is mainly practiced in Eastern Europe, Greece and Russia. In this sense of \"Orthodox\", the question about the difference between Christianity and Orthodox Christianity is similar to asking \"what's the difference between a sandwich and a ham sandwich?\". Eastern Orthodox Christianity is one of the branches of Christianity.\n\nBasically, like the Roman Catholic church, it believes it is the kind of Christianity that carries on the original intent and authority of Christ and His apostles. Unlike the Roman Catholic church, it is not united under the authority of a single pope, but rather it is a group of related churches with their own religious leaders. The Roman Catholic Church and the Eastern Orthodox Church (which also calls itself the Catholic Church) were joined together in most matters until 1054, when they split due to disagreements. One of those was the issue of the authority of the Pope.",
"The standard setup for the early years of the church was the Orthodox church - where 5-6 Patriarchs ruled the Bishopric of their region. One of these was the Bishopric of Rome. The Patriarch of Rome would later come to be known as the Pope. Well the Patriarch of Rome got some lofty ideas about Rome being the most important of the Bishoprics and wanted to place themselves as first amongst equals. \n\nThis and other issues led to a pretty big falling out between Rome (the 'Western' Bishopric) and the others (like Antioch, etc. being the 'Eastern Bishoprics). That eventually sundered the church with the Western Church becoming Catholics led by the Bishop of Rome and the Eastern Church being known as Orthodox and being headed by the Bishop in Constantinople iirc.\n\nThat became a problem when Antioch, Constantinople, Jerusalem, and pretty much everything else in the Middle East being taken over by the heathen Islams, over which a multitude of Crusades were fought. Eventually Constantinople was the last remnant and the Ottoman Turks captured it in 1453. Many Orthodox Christians had to flee and either went west and 'converted' to Catholicism or fled north and east and established strong Orthodox presences in the Balkans, Russia, etc.",
"This doesn't directly answer your question but it might help you see where things diverge and how they relate, none the less it's very interesting to look at and might raise some questions you didn't know you had.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://000024.org/religions_tree/"
]
] |
||
1t786s
|
how is it not entrapment when the fbi provides you the means to commit a crime?
|
A guy was arrested last week for conspiracy to blow up the airport in Wichita Ks but was provided all his bomb materials by the FBI. How is this not entrapment? Why didn't they just stop and try to help him in the beginning instead of providing him the,means to commit the crime?
Here's an article about it...
_URL_0_
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1t786s/eli5_how_is_it_not_entrapment_when_the_fbi/
|
{
"a_id": [
"ce517h3"
],
"score": [
3
],
"text": [
"FBI > \"I hear you're looking for explosives, here you go\" \nvs \nFBI > \"Hey, you should blow up this airport. Here are some explosives you could use\""
]
}
|
[] |
[
"http://mobile.nytimes.com/2013/12/14/us/man-accused-of-airport-bombing-attempt-in-kansas.html?hpw=&rref=us"
] |
[
[]
] |
|
2g5m0m
|
- what does a 3200 rpm stall converter mean, and why do i want it in my modified muscle car?
|
I thought I knew what I'm getting into but now I'm confused. What's the difference between a stock torque converter, a 2800 stall, and 3200 stall?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2g5m0m/eli5_what_does_a_3200_rpm_stall_converter_mean/
|
{
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"text": [
"You only want that if your camshafts power curve starts at 3200 rpm. Stall speed os the max slippage speed the torque converter will allow, ie. break torqueing your car will hold the rpm at 3200 where your cam makes its max power.",
"The idea is that to make the best launch from a standing start, you need enough rpms to spin the wheels and not let the engine bog down. You don't want the rpms to fall below the meat of the torque curve, at any part of the acceleration run. \n\nI guess which one you 'need' depends on the other characteristics of your car; engine size and type, weight, weight distribution, suspension tuning, tyre dimensions and compound. \n\nIt seems pretty common to go for high stall converters, because standard is just more of a compromise that suits normal driving. But I don't think you need to go nuts, unless the rest of the car is also nuts. ",
"If you have to ask you don't need one."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
5itkxm
|
how did articles in the roman languages come about?
|
As far as I know neither ancient Indogermanic languages, nor Latin or ancient Greek had articles yet somehow all (or most) of the modern derivatives ended up having them.
How did this happen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5itkxm/eli5_how_did_articles_in_the_roman_languages_come/
|
{
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"dbaxs9d"
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14
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"text": [
"Actually, Ancient Greek did have articles: it had definite articles, but not indefinite articles. This is why some sticklers for correct grammar insist that you cannot say \"the hoi polloi\", because that translates as \"the the people\".\n\nAncient Greek's definite articles were derived from the demonstrative pronouns of an earlier form of Greek, Homeric Greek. Demonstrative pronouns are words like \"this\", \"that\" and \"yonder\".\n\nThis is also the derivation of Germanic definite articles. For example, in Old English, the phrase \"se dæg\" could mean \"that day\" or \"the day\", while \"þæt ēage\" could mean \"that eye\" or \"the eye\". The word \"se\" became our modern \"the\", and \"þæt\" is now \"that\". The reason the word was sometimes \"se\" and sometimes \"þæt\" has to do with grammar: Old English, like modern German, had three genders; \"se\" was used with masculine nouns and \"þæt\" with neuter nouns. Feminine nouns used the form \"sēo\", and it's believed that this is where our word \"she\" comes from.\n\nIn modern German, the connection between \"the\" and \"that\" is even more obvious: a sentence like \"**Das** ist **das** Haus, **das** ich gebaut habe\" translates into English as: \"**That** is **the** house **that** I built.\"\n\nA similar thing happened in the Romance languages. In Latin, the word for \"that\" was \"ille\" for masculine nouns and \"illa\" for feminine nouns. From those words we get the modern definite articles in French (\"le\" and \"la\"), Spanish (\"el\" and \"la\") and Italian (\"il\" and \"la\").\n\nAs for indefinite articles, they simply evolved from the word for \"one\". In fact, in most European languages, it's still the same word: \"ein Hund\" is German for \"a dog\" or \"one dog\"; \"un chat\" is French for \"a cat\" or \"one cat\"."
]
}
|
[] |
[] |
[
[]
] |
|
826gsd
|
the weird lettering and symbols that are meant to “help” us pronounce words.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/826gsd/eli5_the_weird_lettering_and_symbols_that_are/
|
{
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6,
3
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"text": [
"You mean Diacritical or IPA?",
"What else would you use? It is defined in the International Phonetic Alphabet. You need a system that complex to describe how word are pronounced.\n\nI would agree that is is not useful for most people as you need to understand it. But if you study languages and look at it you can start to learn it. A simple usage is to look at words that you know how it is pronounced and see if parts are the same. If it is not the pronunciation is different. ",
"What you're referring to is the IPA pronunciation guide, and it's a better phonetic alphabet than English has, because each symbol has one, and only one sound. If you know how to pronounce 'special,' then you can infer that 'ʃ' sounds like 'sh' and 'ə' sounds like 'uh'. So, 'special' sounds like 'speshuhl'.\n\nThis is opposed to if you pronounced the word the way it looks. English is such a speekeeall language."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
39zpn5
|
How do plants change the pH of the soil?
|
Observation: [Japanese Stiltgrass] (_URL_0_) (an invasive species to the Eastern US) makes soil slightly acidic. My best guess is due to nitrogen released from decomposition of the roots in the soil. Additionally, the plant may support a certain soil bacteria whose waste product changes soil composition.
Reason for concern: If you wipe the invasive plants out using mechanical control (e.g., weeding, goats, etc.), as opposed to chemical control, they will come back if the area is not seeded with native species. A contributing factor may be soil pH prefrence. Other factors include high seed production, lack of natural predators, and highly disturbed soil.
Reason for asking question: Google and Google Scholar have failed me. Chemical control is not an acceptable option.
All information is helpful.
|
askscience
|
http://www.reddit.com/r/askscience/comments/39zpn5/how_do_plants_change_the_ph_of_the_soil/
|
{
"a_id": [
"cs89coa"
],
"score": [
2
],
"text": [
"The assertion that Microstegium varieties raise soil pH by altering local nitrogen content is asserted by [Ehrenfeld](_URL_1_):\n\n > Soils directly beneath each of the two exotics had higher pH values and higher nitrification rates and often had higher net N mineralization rates than did soils beneath adjacent patches of the most common native understory shrub, Vaccinium pallidum.\n\nThe suggested mechanism is specificity of nitrogen absorption:\n\n > Both species evidently favor uptake of nitrate, which may elevate pH.\n\nSo we have an invasive grass which prefers nutrient poor, high drainage, shaded soils, and which exhibits an allelopathic effect on other nearby plants by preferential intake of more highly acidified nitrogen compounds, which results in a net raising of soil pH. \n\nGenerally, a highly effective solution to this type of invasive plant is soil treatment. Because the plant is competitive with nitrates you cannot rely on nitrogen acidification as a soil treatment. Till soil and treat with acidifying agent, because this invasive grass depends on high drainage soils for tillering growth I would suggest something like a [sphagnum peat moss](_URL_0_[com.lowes.commerce.storelocator.beans.LocatorStoreBean%40fc20fc2] & pl=1 & productId=3319744) which will add weight to sandy soils and lower soil ph. Denser soil will inhibit fast extension beneath the ground, so then you want to seed the area with a stoloniferous competitor species - I do not know your region so I cannot suggest a competitive local grass. The invasive variety has maximum growth efficiency at 25% exposure, so clear the area after tilling in the peat, and seed with a high-light competitor."
]
}
|
[] |
[
"http://www.fs.fed.us/database/feis/plants/graminoid/micvim/all.html"
] |
[
[
"http://www.lowes.com/pd_322730-10799-1310503___?storeNumber=1623&Ntt=peat&selectedLocalStoreBeanArray=",
"http://www.esajournals.org/doi/abs/10.1890/1051-0761%282001%29011%5B1287:CISFFI%5D2.0.CO%3B2"
]
] |
|
2gxhxw
|
What decade is this painting portraying?
|
_URL_0_
Can't figure it out. I say 20s or 30s, my girlfriend says its the 50s or 60s
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2gxhxw/what_decade_is_this_painting_portraying/
|
{
"a_id": [
"ckng2to",
"cknm8c0"
],
"score": [
3,
2
],
"text": [
"Based on the automobiles I would say the 20s/30s.",
"I'm almost insulted by the idea that this is the 50's or 60's, as a former resident of SLC. Utah is backwards but not THAT backwards.\n\nIt'd have to be between the 1880s - when the first street cars were used - and the 1920's, judging by the automobiles. \n[Here](_URL_1_) is a nice picture of Main Street in 1890, and [another](_URL_0_) from 1912. "
]
}
|
[] |
[
"http://imgur.com/MW26mr7"
] |
[
[],
[
"http://en.m.wikipedia.org/wiki/File:Temple_Square_1912_panorama.jpg",
"http://en.m.wikipedia.org/wiki/File:Salt_lake_city_main_street_c1890_ug.jpg"
]
] |
|
15nu0f
|
Do you expend more energy running on a treadmill or a non-moving flat surface?
|
This is a question that some family friends, my parents (both PhDs, one in Physics) and I (only recently finished college) debated at a dinner table a few years back.
The question is whether a person expends more energy running on a treadmill or propelling himself along a flat surface, assuming that he runs the same "speed" on each. To simplify the scenario, we assumed no air resistance and the person does not hold onto the treadmill (or otherwise cheat) while running.
Naively, it would seem that an equal amount of energy is expended in each case, as the person is maintaining a constant velocity and simply overcoming resistive forces to move his limbs at the necessary rate. Are there other factors that should be taken into account?
|
askscience
|
http://www.reddit.com/r/askscience/comments/15nu0f/do_you_expend_more_energy_running_on_a_treadmill/
|
{
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"text": [
"If you look at the surfaces providing the normal force to hold the runner up against gravity, they are both moving in a circular fashion. Earth is rotating and the treadmill belt is rotating. If you stand still on either, you will expend no energy and stay in the same position on the surface as that surface rotates. The only difference is that Earth is much larger and more spherical, so you won't fall off it like you will the end of the treadmill.\n\nHowever, if you run at 5 mph on either surface, you will be expending the same amount of energy and be moving at the same velocity, covering the same linear distance. If the Treadmill had a surface area and rotational period equal to Earth's, there would be no difference in the perception of how much energy you need to expend on either to walk or run at a specific speed (assuming the same gravitational forces, no air resistance, etc).\n\n*edit*: clarification.",
"I'll try to find the citation, but there was an article a little back answering this question. It found that energy expenditure was roughly the same for a treadmill at around a 1 to 1.5 incline. That is, for purposes of Calorie burning, weight loss, & c., I think it's about the same.\n\nHowever, the actual muscle use is different. You can experience this when you finally get out of the gym when the snow melts (if you live in the North), and after your first run your calves hurt like a mother.",
"Ok, I know my flair is not in physics, but the answer is that the treadmill is easier at the same pace, and the reason is pretty straightforward, and you will be led didactically to the answer. First consider energy use while running. \n\nWhy does running take any energy at all? You are simply moving at a constant rate of speed. No acceleration. That's a reasonable first approximation, but it is wrong. On each step you take, you decelerate in the direction you are running (slow down), and accelerate upward, while your center of mass approaches your foot. After your center of mass passes your foot, it accelerates downward and forward. Your velocity profile, in the horizontal, or vertical, directions is roughly sinusoidal. Good runners are much better at decreasing the vertical and horizontal magnitudes of these sinusoids, which enables maintenance of more speed with the same work. So now we understand the basic relation between energy usage and running. Let's go to the treadmill. \n\nOn the treadmill, the inertia of the treadmill is tiny compared to the inertia of the earth when you are running. The treadmill will actually slow down a little when your center of mass approaches your footstrike, and will speed up a little when you push off on your foot. This makes the sinusoidal variations (horizontal, not vertical) smaller, and you do less work to go the same speed. In essence, some of the horizontal accelerations during your run are absorbed by the treadmill. \n\nThe magnitude of the difference between the treadmill and terra firma is dependent on how smooth your running gait is. If you are a fast runner, there is less of a difference than there is for a novice (where the difference can be HUGE). ",
"You can't ignore air resistance, because that's exactly what makes running on a treadmill easier (also the total lack of hills, turns, and uneven footing). "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
2twj15
|
if congress passes a bill that has a 'watered down' version of net neutrality, can't obama simply veto it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2twj15/eli5_if_congress_passes_a_bill_that_has_a_watered/
|
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"Sure, but it goes back to Congress after he vetoes it, and if over two thirds of both the House and Senate (voting separately) vote in favor of the bill, they can override the presidential veto.",
"Obama can veto any bill he wants. Content does not matter. That is part of the basis of the US governmental system's of checks and balances.",
"Sure he can. It's just a matter of deciding whether he wants to take the compromise offered or try pushing his luck to get the whole thing."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
26n46a
|
what was the point of ww1? was anything significant achieved?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/26n46a/eli5_what_was_the_point_of_ww1_was_anything/
|
{
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"text": [
"How the treaties among nations can bring them into a war they do not want to be in. \n\nFor future generations to learn from the mistakes from our past. ",
"[Just listen to this - trust me](_URL_0_)",
"It was about a whole lot of different things for different countries. Most wars (at least from an American perspective) are between two countries over a small set of issues, and can be easily summarized as \"the Civil War was about slavery, states' rights, and the nature of the Union\" or \"the American Revolution was about fair representation, republicanism, and monarchical authority\". Major European wars are a lot more complicated, because every country in the region has a chance to jump in and settle scores.\n\nThe war started as a fight between Serbia and Austria, with the Austrians seeking to suppress a movement in Serbia that was agitating for the independence of Bosnia from Austria (a little bit like the fight over Northern Ireland if the UK had invaded the Republic of Ireland to suppress the IRA). Austria was in the war to defend the integrity of its empire; after the war it was broken up into its constituent parts, so it didn't achieve its objective.\n\nRussia intervened on behalf of the Serbs in an attempt to assert its claims to be the protector of all Slavs - in effect attempting to establish an exclusive sphere of influence over Eastern Europe. When Lenin's government made a separate peace with Germany, it gave up a seat at the table for the final peace agreement, and the remaining Entente powers punished Russia for the betrayal by establishing numerous independent, Western-oriented states in Eastern Europe (as well as providing limited assistance to the counter-revolutionary Whites in Russia proper).\n\nGermany was in an awkward position at the time. It had been the greatest power in Europe since unification in the 1860s, but it was nestled in between an array of great powers potentially hostile to its ambitions. Bismarck had spent most of his career mitigating the threat by making friends with Russia, and sowing discord between Russia and France, but Kaiser Wilhelm didn't have the same appreciation for subtle diplomacy. Russia and France had been growing closer in their opposition to Germany for some time, and the Germans felt that they had to neutralize this potential alliance sooner rather than later, as Russia was growing stronger by the year. They saw an opportunity to support Austria against Russia (and presumably France) and to win a decisive victory now that would firmly establish their position as the strongman of Europe. Obviously they didn't achieve this.\n\nFrance, conversely, was concerned about Germany's growing military power, and still chafing from their disastrous loss to the Germans in the last war. In effect, their goal was to prevent Germany from having its way, and they achieved this handily (for the time being). Germany's closest ally Austria was broken up, Germany's military was largely disarmed, and the Rhineland, the most industrialized part of Germany, was demilitarized.\n\nThe UK is the hardest case to understand. Officially, they became involved after Germany attacked France by way of Belgium - a neutral country under the UK's protection. More to the point, they were very close to France and had been involved in an arms race with Germany over the last decade, so it was natural for them to honor their various agreements with France and Russia. It isn't entirely clear what they hoped to get out of the war; some argue that they were afraid a German victory might lead to German control of the English Channel, and that this would be a devastating blow to long-term British security. In any case, like France, their goal was primarily to contain Germany.\n\nThe US didn't get involved until much later than the other combatants, and with a very different purpose. President Wilson was an idealist, and he and his chief adviser Colonel House sought to spread contemporary American ideas of democracy and national self-determination throughout Europe. They didn't have any particular animosity towards Germans specifically, except insofar as Germany, Austria, and the Ottomans were all anti-democratic sprawling empires. Unfortunately, Wilson's hopes for Europe were at odds with the more self-serving objectives of Britain and France, and he had to compromise with them quite a bit to get a peace treaty. A number of independent nation-states were created, particularly in Eastern Europe, but without American participation in the League of Nations or a willingness in Britain and France to back the Treaty of Versailles with force, most of the positive results of the war were lost within 20 years.\n\nTL;DR Everybody wanted something different out of the war; it wasn't \"about\" any one thing. The victors had conflicting goals, so they didn't get everything they wanted, and none of them put much effort into protecting what gains they did manage, so the war accomplished little in the long run."
]
}
|
[] |
[] |
[
[],
[
"http://www.dancarlin.com//disp.php/hharchive/Show-50---Blueprint-for-Armageddon-I/First%20World%20War-World%20War%20One-Great%20War"
],
[]
] |
||
1h8njz
|
Could we workout for longer if we inhaled pure oxygen during the process
|
askscience
|
http://www.reddit.com/r/askscience/comments/1h8njz/could_we_workout_for_longer_if_we_inhaled_pure/
|
{
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"Inhaling pure oxygen would theoretically increase the rate at which your body could produce energy. However this is dependant on there not being any metabolic bottlenecks that exist so that the extra oxygen delivered to the muscle tissue is utilised in generating ATP. Your breathing rate will be relatively unaffected as your body has no way of monitoring O2 levels, only CO2 levels which would only change if the metabolic rate changed. \n\nSo assuming there are no metabolic bottlenecks (eg. enzymes in glycolysis or beta-oxidation of fatty acids) that are limiting the rate of ATP production then the extra O2 would allow for longer muscle contractions before failing. Whether this translates into a longer workout would be more about efficiency of fat metabolism, phosphocreatine levels and glycogen levels in the muscles and liver, as these will determine how long energy can be synthesised. For reference you only get a few seconds of high intensity muscle contraction before your muscles run out of energy and must make more. ",
"Short answer, probably not. Oxygen availability is not typically limiting to exercise, the limitation in VO2max is more to do with blood flow and cardiac output than oxygen exchange in the lungs. Blood oxygen saturation remains high (in the order of 95%) in normal air, I doubt there would be benefits to maintaining 100% saturation. Consider athletes who blood dope or use EPO, they increase blood oxygen content by increasing blood cell count, ambient air still has more than enough oxygen to supply them.\"deoxygenated\" blood is a misnomer as there is still oxygen in it (and quite a bit too) just not as much as arterial blood. Room air is about 21% oxygen normally (sea level), during exercise the air you're breathing out is still probably 14-15% oxygen at worst. \n\nAn interesting thing to consider (which unfortunately I'm not well versed in) is central fatigue, ie fatigue in the brain. In hypoxia, it appears that you fatigue faster because your brain tells your body to stop, not because of any limitation at the muscle. So perhaps with increased oxygen maybe central drive would go for longer? But at normal oxygen levels I don't know how much central fatigue contributes.\n\nTL;DR - exercise is not usually limited by gas exchange at the lungs, so more oxygen there will have little benefit."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1pql1e
|
why is the media not referring to the lax shooting suspect as a 'terrorist'?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1pql1e/eli5_why_is_the_media_not_referring_to_the_lax/
|
{
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"text": [
"There is no evidence he was a terrorist, was involved in terrorism, had connections to terrorist organizations, or was doing this act for terror purposes. This was just a crazy/suicidal guy with a gun shooting people, though its currently thought he had \"anti-govt\" views, but not terrorism."
]
}
|
[] |
[] |
[
[]
] |
||
23belf
|
Are electricity and magnetism related in a similar way that space and time are related?
|
I know that as one approaches the speed of light, several things happen: Space and time change in some proportional manner, mass and energy both increase (obviously because they are the same thing), and electric fields become magnetic (and vice versa I think). I can conceptualize why time slows down, why space shrinks, and why mass increases using fundamental laws of relativity, but I can't see why electric fields in motion should produce magnetic fields. Is there any way to conceptualize it, or is the answer all in the equations?
|
askscience
|
http://www.reddit.com/r/askscience/comments/23belf/are_electricity_and_magnetism_related_in_a/
|
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"text": [
"An electric charge at rest \"produces\" an electric field but no magnetic field. When a charge moves it also produces a magnetic field, via the Ampère(-Maxwell) equation. When it moves faster, the magnetic field is larger.\n\nNow the quantity *E*^2 - *B*^2 is Lorentz invariant, which means that it stays the same under Lorentz boosts, which is the formal way of saying thing like \"approaching the speed of light\". So as you change the velocity of your reference frame, electric field can be traded for magnetic field in a certain way. \n\n\"Electric fields in motion\" is not really a useful way of thinking about it, looking at the charges that produce the field is much better. However the equations for electric and magnetic fields under Lorentz boosts can be found in for instance D. Griffiths, Introduction to Electrodynamics, chapter 12, or in [Wikipedia](_URL_0_).",
" > Are electricity and magnetism related in a similar way that space and time are related?\n\nThere is at least one relationship that I think it would benefit you to understand. Energy and momentum are related in a similar way that space and time are related, as are electricity and magnetism.\n\nIn ordinary three dimensions, we consider energy to be a scalar quantity (a simple number, equivalent to a 1x1 matrix), and momentum to be a three-dimensional vector (i.e. a column matrix -- 1xn where n is 3).\n\nBut we can model time as if it were a dimension, like space, which leads us to relativity. It's easy to generalize a scalar quantity to higher dimensions -- it doesn't change, it stays a scalar 1x1 matrix. But to generalize a vector quantity requires an additional degree of freedom. In relativity, momentum is not a 3-dimensional vector; it's a 4-dimensional vector. If each dimension corresponds to a momentum in that respective direction, what corresponds to momentum for the time dimension?\n\nTurns out it's the energy (along a conversion factor of c^(2) or sometimes c based on conventions) -- you can think of energy as a \"momentum through time,\" similar to how ordinary momentum in any direction is a momentum through space. Just like how objects moving through space with momentum can affect other objects in space (but objects with no momentum, relatively, can't), so too do objects with energy affect other objects throughout time -- without energy to drive it, change is non-existent.\n\nThat's super cool right, but what about electricity and magnetism? Well, in classical mechanics, the electric potential is a scalar potential (meaning there is a scalar quantity for every point in space -- the electric potential), and the magnetic potential is a vector potential (meaning there is a vector quantity for every point in space). Since space is 3-dimensional, the magnetic potential is a 3-dimensional vector -- a potential corresponding to each direction in space.\n\n(Edits: I was too loose with distinguishing potentials and fields, so I've cleaned this part up a bit to be more accurate -- thanks /u/tagaragawa!)\n\nBut in relativity, space and time are related into a 4-dimensional space, and the magnetic potential vector must be 4-dimensional! What should go into the time component for this relativistic 4-vector?\n\nTurns out if you put in the (scalar) electric potential in, you get the [electromagnetic four-vector](_URL_3_) which describes the electric and magnetic potentials as a single potential, from which the (unified) electromagnetic field can be derived.\n\n > Space and time change in some proportional manner, mass and energy both increase (obviously because they are the same thing)\n\nActually, mass and energy *aren't* the same thing, the same way that a square and a rectangle are not the same thing. A square is a rectangle, but the opposite is not necessarily true. Likewise, mass is a form of energy, but the opposite is not necessarily true -- not all energy is mass.\n\nYou *can* sort of consider energy part of a \"relativistic mass\" -- but really that's a fancy way of saying \"energy with a conversion factor of c^(2) so that it's in units of mass.\" It's not really the same thing, it just can be put into the same units. You *cannot* use relativistic mass in every equation that you can use rest mass in, and still get correct answers.\n\nFor example, Einstein's famous equation E=mc^(2), defines \"m\" as the \"rest mass,\" and it's *not* the full equation. The full equation is E^(2)=(pc)^(2) + (mc^(2))^(2), where \"p\" is the momentum. If you set p=0, the equation reduces to E=mc^(2) -- so that equation only applies to particles with mass that are at rest (zero momentum). If you instead set m=0, you get the equation for the energy of massless particles, which is E=pc. That's the energy of a photon, which is experimentally measured.\n\nBut if instead you try to use the relativistic mass term (M=γm, where \"γ\" is the Lorentz factor and \"m\" is the rest mass), and tried to use E=Mc^(2) in every situation, then massless particles would need to have zero energy (since m=0 and anything times zero is zero, including γ). But we know that in reality this is not true, so the relativistic mass M cannot be a fundamental part of Einstein's equation. Instead we have to use the full equation that includes *rest* mass, and an added term from momentum.\n\n > I can't see why electric fields in motion should produce magnetic fields. Is there any way to conceptualize it, or is the answer all in the equations?\n\nIt's all in the transformations between reference frames. There are some textbook ways of teaching how to conceptualize it, but you have to be familiar with the [Lorentz transformation](_URL_0_).\n\nTry watching [this video](_URL_2_) if you aren't already familiar with visualizing Lorentz transformations, then [read this explanation](_URL_1_) of how Lorentz contraction demands that a static electric field be transformed into both an electric and magnetic field (or vice versa) because of a Lorentz transformation. But the gist of it is, magnetic fields can be thought of as arising due to differences in Lorentz contraction of space, in order to guarantee that the same phenomena (electromagnetic physics) happen in every reference frame.\n\nHope all this helps!",
"I would encourage you to watch [this video](_URL_0_) because it explains that relativistic effects, combined with the electric force, result in what we describe using a \"magnetic field\" and \"electric field\".\n\nCoupling is pretty confusing. But it just means that it isn't really a causality in one direction, it is the both directions that affect each other. Spacetime in relativity is a sort of geometry, with a special metric of d^2 = x^2 + y^2 + z^2 - t^2 that is invariant when you change reference frames.\nIn electromagnetism it is less simple, there are fields that consist of vector valued functions of the entire space that are thought of as varying with time as a result of motions of charged bodies. Other comments here give a more detailed description of how all that works.\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Relativistic_electromagnetism"
],
[
"http://en.wikipedia.org/wiki/Lorentz_transformation",
"http://en.wikipedia.org/wiki/Relativistic_electromagnetism#The_origin_of_magnetic_forces",
"http://www.youtube.com/watch?v=C2VMO7pcWhg",
"http://en.wikipedia.org/wiki/Electromagnetic_potential"
],
[
"http://youtu.be/1TKSfAkWWN0"
]
] |
|
52vinv
|
How much, if at all, does the moon's gravity effect satellite's orbits?
|
Specifically do we have to include a moon's gravity variable in satellite orbiting calculations?
|
askscience
|
https://www.reddit.com/r/askscience/comments/52vinv/how_much_if_at_all_does_the_moons_gravity_effect/
|
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"It depends. There are a lot of contributing factors to the acceleration of an earth-orbiting satellite: earth gravity, atmospheric drag, the moon and sun, etc. The relative magnitude of these contributions depends largely on the *altitude* of the orbit. For example, for low-earth orbits (e.g., the ISS), atmospheric drag can be a larger effect than the moon's gravity.\n\nThere is a useful figure 3.1, p. 55, in Montenbruck and Gill's \"Satellite Orbits\" text that shows these contributions; a Google book search for \"montenbruck gill satellite orbits fig 3.1\" should get you there.\n",
"Yes, the moon's gravity exerts influence on satellites. This is especially important for geostationary satellites where very small alterations in their orbits could make them no longer geostationary. \n\n > moon's gravity variable\n\nUnfortunately is isn't that simple. The distance between the moon and the satellite is constantly variable as both things are orbiting. \n\nAnalyzing deviation from a mathematically ideal orbit is called [orbital perturbation analysis](_URL_0_. This gets incredibly complicated very quickly, as the orbits of the moon and Earth themselves are also irregular. \n\nSatellites have some propellant onboard for station-keeping, which is regularly correcting for irregularities in its orbit. ",
"This is actually pretty easy to figure out with a quick back of the envelope calculation. The acceleration an object feels from gravity is just MG/(r^2 ). If we plug in values for Earth's mass and the Moons mass and look at a couple of different orbital locations we can get a feel for the relative pull between the earth and the moon. \n\nFor a satellite on the outer edge of Low Earth Orbit (LEO), the orbital distances is about 2000km above the surface of the earth (r = 8371 km). The moon as a semi-major axis of about 385000km so that means this satellite is roughly 377000 km from the moon. so if we take the ratio of the acceleration toward the moon and the acceleration from earth and plug in these values we get 5.76*10^-6 . This is a very small correction, and is also the largest it will be. As the satellite and moon orbit the earth they will move out of this idealized system where they fall exactly on a line from the earth through the satellite to the moon. \n\nLets consider now a satellite in Geosynchronous orbit, much further from the earth/closer to the moon. We'll again assume the maximal configuration and take the ratio of the accelerations (r = 48000km from the earth now). For GEO orbit we get a ratio of 2.428*10^-4 much larger than before, but still quite small, and again coming from the maximal configuration. \n\nLooking at these numbers it seems like the moon's gravity on a satellite is going to be pretty much negligable when launching the satellite. That said even these small numbers over time can start to significantly affect the orbit so people in charge of operating these satellites while their in orbit will have to consider the Moon's gravity and occasionally have the satellite make orbital corrections to account for it. ",
"People here seem to he largely forgetting one key point. The acceleration the Moon causes on the satellite is almost the same as the acceleration the moon causes on the Earth. The perturbations in the satellite's orbit, then, can be either caused by the slight gravity differential between the Earth's center of mass and the satellite's orbit, or are caused by the difference in angle between the Earth/Moon line and the Moon/satellite line. These are miniscule, but are most pronounced when the satellite is about (a tiny bit less than) 90 degrees away from the Earth/Moon line."
]
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[] |
[] |
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[],
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|
2c8qwj
|
why do so many games have a "start" screen where you have to push a button before they decide to start a several minute loading process? (i'm looking at you, battlefield 4)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2c8qwj/eli5_why_do_so_many_games_have_a_start_screen/
|
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"The primary reason is going to be player input. Let's say you omit that start screen, and just begin loading. All of a sudden, the player is sitting there, as you say, for minutes at a time, before anything happens. Is the game working right? did I do something wrong? is it frozen?\n\nBy forcing a player to hit start, it provides feedback that indeed, things are proceeding correctly. If it doesn't work, then you can safely begin troubleshooting reasons it might not be.",
"Gamedev here.\n\nI usually create a splash screen that appears immediately after the user runs the application ensuring that the game is actually running and expecting user's input. It contains a background image, music and ~~three~~ four main buttons: New Game, Restore Game, Options and Quit. No loading happens at this point (unless the game is heavy then I'd let some main libraries load in the background that won't have apparent affect to the user). The splash screen is a very good choice when developing a game in case the user have run it by mistake, or had a change of mind or any reason to quit without going through the waiting phase.",
"Another reason for having a clicked start button is that for multi-windowed environments, the \"focus\" may be on another window, so when you start using your arrow keys you'll be using them on your porn window rather than your game window. By forcing you to click on the game, you are bringing the focus to it so it won't seem to be not working.",
"Gamedev here:\n\nthe press start screen is used to determine the \"primary\" user. \n\nThe bit that most people probably dont realise is that once you've hit start, (and you've signed into XBL/PSN/Steam) We're going to talk to the system platform to get your profile, controller preferences, gamertag etc etc, and with a game like BF4, we're going to talk to service platform(s) to get what content you own, your game history, all your battlepack information, making sure you're not banned, downloading messaging, advertising, etc etc.\n\nOn top of straight up loading the data off the disk, there's quite a lot of back and forth from a communication POV, this takes time, especially when there's multiple services and systems involved. Its also not something you can easily hide as we need to know who the primary player *is* before we can go and do all this work.\n",
"Sometime the ''Splash screen'' is used to determine which controller will be used as primary input for the game.\n\nFor consoles, it might be controller 1 to 4.\n\nFor Pc, it might be the keyboard or the controller.",
"All console manufacturers have a first party requirement of having a start screen and an attract mode which is usually a video. So and game cross developed for PC and consoles will have them unless the dev took the time to remove them from the PC release. The mass effect series comes to mind as a good example of a start screen then the menu screen. \n",
"Having never played Battlefield 4, I'm going to guess you mean the start screen many games have that appears after the initial game load and credits play, but before the options, mode select, etc menus.\n\nThis is a throwback to arcade cabinets, where you would have an attract mode that plays when there is no one touching the controls. While many games have ditched the attract mode (or most players hit start before the attract mode can start) the start screen has become something of a tradition in gaming.\n\nI suppose it still matters in cases where individual controllers sign on with different accounts (what, read the other comments in the thread, me? nah!)",
" Another reason is that on the Xbone, Macrosoft has a pretty strict requirement that the game be responsive within a set amount of seconds after being told to launch (something like 3-5 seconds), as in, the title must have some sort of interactive element. I guess this is for the previously mentioned reasons of reassuring the player that everything is working normally and to not leave them waiting.\n\nsource: Am an xb-one games tester, and have had to occasionally fail a game for the start screen taking too long.",
"I actually considered this not too long ago. \n\nAnother reason I don't think has been explored relates to accidental keypresses.\n\nImagine without a splash screen. The game turns on, loads through producer screen, etc. At this stage most users are mashing \"x\" or whatever primary key for their system. The game suddenly loads, and because the user was mashing keys, whatever is initially highlighted is selected.\n\nThe user is now starting a new game, often with lengthy start cut-scenes, when most likely they actually want to load a saved game.\n\nForcing the user to press \"start\" while ignoring other input forces them to move their finger from the primary buttons, and makes it known to the user the main game menu is about to be displayed and active.\n\n",
"Another point to consider is that arcade cabinets would have a \"insert coin\" screen and has transferred over to consoles. \n\nAlso it makes as a great advertisement in store or booth, previous games would have a cutscene or gameplay that would appear if no one pressed start to entice a player",
"Imagine the game as city traffic. The traffic has to get from point A to point B. Lets put the traffic into Rush Hour mode. Now we have enough traffic to where getting from point A to point B will take longer. As the traffic moves, that represents assets (audio, images, textures, scripts, etc) being loaded into your memory from your hard disk. Some games have traffic cops, which are essentially asynchronous tasks that load the assets in the background of the \"start\" screen sort of like directing traffic at a red light. \n\nWith a PC, all of the cars are self-driving smart cars which are in sync, which means lower load times.\n\nWith a Console, all of the cars are broken down 1980 Geo Metro's which can only get into 2nd gear. Many times, accidents happen, slowing the traffic even more.\n\nWhen it comes to games like Battlefield or anything with online multiplayer, imagine construction zones which clog certain lanes of the traffic. As you and your friends all move to a certain location, the traffic might get rerouted at different stop lights, which increase latency and synchronization time.\n\nThis is about as simple as I can put it."
]
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3ut5zh
|
why is it that most corporate jobs don't have unions?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3ut5zh/eli5_why_is_it_that_most_corporate_jobs_dont_have/
|
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"Many corporate jobs are achieved by skill. So wage and benefits are given accordingly. There is a lot less likely of a chance of near slave labor in an office building than in a factory/warehouse.",
"When I worked for Boeing, there was an attempt by some to unionize the engineers. It was voted down. Most of the engineers preferred having raises based on performance rather than flat increase across the board.",
"Because most white collar workers are smart enough to know that a union would be detrimental to their ability to receive bonuses, pay/promotion based on performance, and that their competitors would have a competitive advantage. "
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||
40ftla
|
During WW2, were there any jews who actively collaborated with the Nazis to hunt down other jews?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/40ftla/during_ww2_were_there_any_jews_who_actively/
|
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"Ok, first off, it is important to understand that this is an extremely touchy and controversial subject even within academia today.\n\nThe short answer is that there were indeed Jews who collaborated with the Nazis though most of it was part of the perfidy with which the Nazis ran their system of genocide, basically actively forcing people to assist in their own murder.\n\nThe more nuanced answer must start with how the Nazi system of deportation etc. worked. In Germany in a model they would transfer to most of Western Europe, Jewish communities had their own official infrastructure in place. Meaning they had an official organization with elected officials running stuff like determining who was to be become Rabbi, organizing community life and so on. These community organizations (Gemeinde) were essentially left in place by the Nazis and placed under guardianship and overall control of the Nazis. They determined who was to become Judenältester (Jewish elder) as the guy who was ultimately responsible for running the whole thing. It was part of the Nazi enforced mission of these communities to not only run stuff such as Jewish hospitals and homes but also the transit camps in which Jews awaited deportation and to compile the lists of who was to be deported. In essence the Gestpo ordered the Jewish community of Berlin for example that next week 8000 people were to be deported to the east. And then under the threat of deportation and death, these communities had to compile the lists of who was to be deported.\n\nOften it was not just limited to the lists but also the forced responsibility of these communities to gather then people for deportation. To this end, a Jüdischer Ordnungsdient (Jewish Order Service) was to be established. This was in essence a sort of police force consisting of members of the Jewish community charged with arresting people and bringing them to the detention sites where they awaited deportation.\n\nThis system was put in place in much of Western Europe as well as in the Polish Ghettos where the Jews inside the Ghetto were essentially placed under self-managment with only the higher ups receiving orders from the Nazis locally in charge.\n\nThe difficult and controversial question comes up around the behavior of the officials of these Jewish communities and of the Ordnungsdienst and revolves around the fact that they essentially collaborated but did so under the threat of deportation and death but also with the - in the end unbeknownst to them imaginary - perspective of being able to at least save some of their people.\n\nThe difficulties of these situations are exemplified by Adam Czerniaków, head of the Warsaw Ghetto Judenrat. Czerniaków was made head of the Judenrat in the Warsaw Ghetto and helped draw up lists for \"resettlement to the East\" as was the Nazi code word for deporting people to their death. When he found out what that meant and when his Nazi superior demanded he send 6000 Jewish orphans to their death in 1942, he committed suicide for he saw no way out. We know of his impossible moral struggle from his dairy which survived the war and has been published, exemplifying the dilemma in which people like himself or members of the Jewish Ordnungsdienst found themselves in.\n\nSeveral survivors also make mention of Jewish Gestapo collaborators who hoping to avoid their own deportation did indeed help the Gestapo. However, in contradiction to other collaborators, they always operated under the dire threat of their own death by the hands of the Nazis and that would also be their fate ultimately, which is why we don't have any accounts of these people.\n\nAgain, I can't stress enough that the issue of Jewish collaboration in the Judenräte, the Ghettos and the camps is incredibly difficult since it always operated with the faint hope of saving oneself, a loved one or larger numbers of the total community and that it always was intended this way by the Nazis as a way to force their victims to a certain degree of complicity in their own murder.\n\nSources:\n\n* Trunk, Isaiah Judenrat: the Jewish Councils in Eastern Europe under Nazi Occupation, with an introduction by Jacob Robinson. New York: Macmillan, 1972.\n\n* Michael Berenbaum: [Judenrat](_URL_0_)\n\n* Dan Michman: 'On the Historical Interpretation of the Judenräte Issue: Between Intentionalism, Functionalism and the Integrationist Approach of the 1990s', in: Moshe Zimmermann (Hrsg.), On Germans and Jews under the Nazi Regime. Essays by Three Generations of Historians. A Festschrift in Honor of Otto Dov Kulka (Jerusalem: The Hebrew University Magnes Press, 2006), S. 385–397.\n\n* Doron Rabinovici: Instanzen der Ohnmacht. Wien 1938–1945. Der Weg zum Judenrat. Jüdischer Verlag bei Suhrkamp, Frankfurt am Main 2000.\n\n* Aharon Weiss: Jewish Leadership in Occupied Poland. Postures and Attitudes. In: Yad Vashem Studies. 12, 1977, S. 335–365.\n\n* Adam Czerniakow's diary."
]
}
|
[] |
[] |
[
[
"https://www.jewishvirtuallibrary.org/jsource/judaica/ejud_0002_0011_0_10457.html"
]
] |
||
342cyz
|
lagrange points for a planet with two moons
|
So, Google was no help regarding this question and I'm hoping someone here can help me out. I understand very basically how Lagrange points work (five locations of equilibrium between opposing gravitational forces and centrifugal forces) but what would happen in a system with more than three bodies?
Taking Mars as an example, it has two moons. If the two moons don't share the same orbital path, one moon would be passing through the system created by the planet and the other moon. What effect would that have on the Lagrange points? Can Lagrange points even exist in this configuration?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/342cyz/eli5_lagrange_points_for_a_planet_with_two_moons/
|
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"It would depend a lot on the relative sizes and positions of the bodies. Taking the solar system as an example: Jupiter has fairly large concentrations of asteroids at some it's lagrange points, because it and the sun are much more massive than anything nearby which would disrupt the system. By contrast, Earth doesn't have big concentrations of asteroids at the same solar/Earth lagrange points because Jupiter would tend to disrupt the system. \n\nThere's so many things that would change the situation in your moon question - relative masses, orbits, whether the orbits are in any sort of resonance, all might make a difference. But broadly speaking, you'r intuition is right, that more bodies tends to make lagrange points less stable.",
"Could the Lagrangian point \"shift\" or \"change\" its spatial coordinates in space based on the phase of the orbit of the twin moons? Assuming a satellite or a space station with the Lagrangian point would also shift along with the point? Or would it move out of the Lagrangian point and then be subject to the gravitational force of some body like the planet or one of the moons?"
]
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[] |
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[],
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|
3v10z6
|
why hasn't microsoft word made times new roman the universal font?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3v10z6/eli5why_hasnt_microsoft_word_made_times_new_roman/
|
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"Because TNR is ideal for some uses, but would be awful for many other things.\n\nFor example, in a spreadsheet it would be hard to read, and on a shop-front it might send the wrong message.",
"It used to be the default font because it looks best when printed out. Now fewer things are printed out so they switched to calibri which is easier to see on a screen",
"Fonts with serifs (the little embellishments on the end) are great in printed materials, but are harder to read on a computer screen. It's why most of the Internet uses sans-serif fonts, like Arial or Helvetica, and why Word switched the default font from Times New Roman (a Serif font) to Calibri (a sans-serif font) in 2007- Microsoft noticed that people had stopped printing out most Word documents and instead were reading them on a laptop or tablet."
]
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|
[] |
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||
5w8cd4
|
if calories are the measure of how much energy there is in food - how can things be 0 calorie?
|
I mean - isn't there still energy in those 0 calorie cookies? Would you starve to death if you tried to live on those and Coke Zero?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5w8cd4/eli5_if_calories_are_the_measure_of_how_much/
|
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"Yes. It has zero nutritional value. Zero calorie stuff is just a bunch of chemicals that your brain tells you is tasting good.",
"Yes, you'd starve. 0-calorie food is made of stuff you can't digest. Since you can't digest it, it comes out in basically the same form it came in, which often causes... intestinal difficulties.\n\nDue to some wiggle room in labeling laws, you can have up to 5 calories/serving and still label food as 0-calorie.",
"ok, so essentially calories are the value attributed to the amount of simple and complex sugars that a material has inside of it. Wether that's carbohydrates, fats or protein calories are the estimated value of how much energy that food stores in it.\n\nCalorie free, or extremely low-calorie foods use substitute ingredients to provide something that may still have nutritional values, however provides very little in the way of caloric value.\n\nCase in point, Coke Zero. While it helps quench your thirst, and will settle/calm your stomach, it will not provide you any significant boost in energy. This is because Coke Zero is made with many inorganic and processed chemicals that will not provide your body with beneficial nutrition or chemical based energy that it needs. The chemicals pass through your body almost undisturbed until you either pee/poop them out. The only useful thing is whatever water your body can strip chemicals off of to use.\n\nOther foods, such as rice cakes, may have 1-2 calories, however still have other minerals and nutrints, such as sodium or Vitamin A, but still have no fuel to add to the mix.\n\nIts like your body is a car. Do you need brake fluid? not every day. Do you need oil? Yes, but in small amounts every 1-4 months. Do you need Gas? Yes, every 2-5 days depending on how you drive.\n\nIn this instance, equate GAS to CALORIES. Oil, transmission fluid, etc... these are going to be other minerals and vitamins you NEED, but arn't actively used to make you GO. They work with the things that make you GO to make sure you keep GOING, but they arn't the fuel your body burns."
]
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|
[] |
[] |
[
[],
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|
ch8iq6
|
How was the production of coins organised in ancient Greece / Rome (or even after)? How did rulers ensure the people who made coins didn't steal them?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ch8iq6/how_was_the_production_of_coins_organised_in/
|
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"At least in the Late Republic, but I think also earlier and definitely later, the Romans had \"governmental\" mints. On the Roman Imperial coinage (RIC), the mark SC, Senatus Consulto, showed that the coin was created in one of these mints. Before that, usually the mint masters (tresviri monetales) would put their name on the coins. This way, one could see which coin was made by decree of the senate and which one wasn't. \n\nThe coins would be produced in batches: there would be a mold with an reverse and a die with an obverse, which would then both be imprinted in the metal(either gold, silver or bronze).\n\nI'm not sure how they made sure that nobody stole coins while producing, but the tresviri monetales come from senatorial families, so they were of high(er) status. The senate would also know these people personally, so I don't think stealing coins from these mints was profitable.\n\nMaybe these sources are interesting for you:\n\nHamilton, C. D. (1969, January). The tresviri monetales and the republican cursus honorum. In Transactions and Proceedings of the American Philological Association (Vol. 100, pp. 181-199). Johns Hopkins University Press, American Philological Association.\n\nWallace-Hadrill, A. (1986). Image and Authority in the Coinage of Augustus. The Journal of Roman Studies, 76, 66-87.\n\nMetcalf, W.E., “Roman Imperial Numismatics”, in: D. Potter (ed.), A Companion to the Roman \r\nEmpire (London 2006), pp. 35-44.\n\nHope this helps!",
"The production of coins within Republican Rome was under the direction of the *tresviri monetales*. They are referred to by Pomponius (*Digest*) as the *triumviri monetales aeris argenti auri flatores* which is basically 'the three men for casting and striking of bronze, silver, and gold.' The position of *monetales* was an introductory position into Roman public life. When such position was introduced is unknown, some scholars suggest a date of 290-289 BC based upon the introduction of other similar offices, some scholars suggest 269 BC given the date that a Roman mint began to produce silver coins, and some just believe that we do not know but establish the foundation to the 3rd century BC.\n\n\nThe mint of Rome was a building on the Capitoline Hill located next to the temple of Juno Moneta. The *triumviri monetales* would supervise the production of said coins including the type (design) included on the coin, which would then be struck by the mint workers (*monetarii*). It was under there supervision then that it would be expected to understand how many coins were to be produced. The method of striking coin was simple. The designs for the obverse and reverse of the coins would be engraved into metal known as *dies*. One die would be placed in an anvil and the other in a metal bar, the soon to be coin was placed inbetween and a hammer was then used to make an imprint.\n\n\nThe production of coins was pretty standard between 218 BC - 140 BC. Bronze coinage (*aes grave*) had standard designs for the most part made up of six types: the As (Head of Janus/Prow); the Semis (Head of Saturn/Prow); the Triens (Head of Minerva/Prow); the Quadrans (Head of Hercules/Prow); the Sextans (Head of Mercury/Prow); and the Uncias (Head of Roma/Prow). Likewise, the silver coins (*denarii*) for the most part included designs related to the state such as Roma, Hercules, the Wolf and Romulus and Remus, the Dioscuri and so on.\n\n\nIt was in the 130s BC in which we begin to see the iconography of coins beginning to change annually with the focus being political propaganda. The reasoning behind this change is suggested as being because of an increase in political competition during the period (I myself believe it had been ongoing for decades prior). Another influence may have been the *lex Gabinia Tabellaria* in 139 BC which introduced secret ballloting - the use of coins as propaganda then became more important. From then on the position of *monetale* became important as one could issue coins outlining the achievements of their families and alike (this could have also been simply a way of remembering their family members - something which was important in Republican Rome).\n\n\n & nbsp;\n\n\nIn terms of stealing within the Roman Republic, I am not aware of any cases of the mint itself being robbed. The mint was provided with the metal they striked by either the state or individual citizens so they would know how much metal they provided and therefore how much coin they should receive. However, there was issues with forgery.\n\n\nAccording to Pliny (*Natural History*. 33.13.46), it was Livius Drusus (tribune of the plebs) in 91 BC who produced a silver coin alloyed with one-eight of copper. According to Cicero, the issue became that bad by 85 BC that the tribunes of the people and praetors took action to standardise the value of currency, because (*On Duties*. 3.20.80):\n > ...or at that time the value of money was so fluctuating that no one could tell how much he was worth.\n\n\nSulla introduced a law in 82 BC as dictator known as the *lex Cornelia de Falsis* which considered forgery as an act of *falsum* (fraud) and a *crimen publicum* (crime against the public) and would result in severe punishment.\n\nIf you are interested further in books then really the best place to start is M. Crawford. More recently published books will no doubt reference back to Crawford.\n\nCrawford, M. (1974). *Roman Republican Coinage*, London.\n\nCrawford, M. (1985). *Coinage and Money under the Roman Republican: Italy and the Mediterranean Economy*. London.",
"Actually during the reign of Aurellian there was a rebellion of mint workers. It's not very well documented, unfortunately, but what we do know is that the person in charge of the Roman mint, a gent by the name of Felicissimus, allowed the the silver content of the coins to slip below official levels with the extra silver being pocketed by the workers. Felicissimus was executed for allowing this to occur, and his workers rebelled en masse. The Roman mint was temporarily shut down, which happened to be one of the steps in making the city of Rome less important to Romans. In about a decade the official capital would be Milan (which happened to have its own mint working in overtime while Rome's was shut down)."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3ent4e
|
why does germany have such a strong influence over the eu?
|
Seems like Angela Merkel and her effect on the EU is always in the news.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ent4e/eli5_why_does_germany_have_such_a_strong/
|
{
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"text": [
"Germany is the EU's strongest economy and has the largest population. Why wouldn't they have a strong influence?",
"Germany does have the largest economy in the EU, and the largest population, but that is probably a little more simplistic than the actual situation; France, Italy and the UK are also powerful EU member states.\n\nGermany, and to a lesser extent France and Belgium, are the most \"European-minded\" countries in the EU. They place a lot of value on European politics and ideas, contrasting especially with the UK, which has always been on the edge about the EU.\n\nAlso, most Germans, but particularly Merkel, are relatively conservative and supportive of the austerity policies promoted by the European Central Bank. The media covers Merkel a lot because most of the EU politics that Americans care about are related to these austerity policies, which are causing all the trouble in Greece, and she is their most powerful European proponent.\n\nEDIT: Partially because Germany's economy is so powerful, many of the loans given to the Greek government were provided by German banks. This makes them particularly invested in how the debt crisis is resolved."
]
}
|
[] |
[] |
[
[],
[]
] |
|
fnkud3
|
Can anyone explain how someone can be an asymptomatic carrier of disease?
|
askscience
|
https://www.reddit.com/r/askscience/comments/fnkud3/can_anyone_explain_how_someone_can_be_an/
|
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"There's always a portion of the population that falls into this category, even for virulently lethal diseases like the black plague. Some immune systems hit that point where the person shows no symptoms, but still carries a sufficient amount of the virus to infect others. Some people will not even be carriers, but are simply immune to a particular virus.",
"There are actually four ways that you can be asymptomatic:\n\n1. Early in the infection you can start shedding virus before you start showing symptoms. That might be true for everyone. I've heard estimates for perhaps 24 hours before symptom onset.\n2. You might have such mild symptoms and not recognise you have COVID-19.\n3. You might have rarer symptoms and not recognise you have COVID-19. You might for instance just have a sore throat or diarrhoea—rather than having the more usual high temperature, dry cough and muscle fatigue. It's not clear how many people move from these rarer symptoms to more full blown \"standard\" symptoms later.\n4. You might have no symptoms at all.\n\nI find Number 1 the most scary in some ways as suggests there is no way of avoiding contact with carriers in the early stages of the disease. Numbers 2-4 are also problematic, but at least they suggest the current mortality rates are probably exaggerated which is good news.\n\nFrom a semantic point of view I only think 1 and 4 are truly asymptomatic, but it's clear that all four uses of the words are going to be mushed together for the foreseeable future.",
"Keep in mind that the period that a person is asymptomatic can be very short. \n07:00 you feel fine but the virus has reached your throat, you can exhale particles into other people's face (when very close). \n12:00 when you normally wouldn't, you cough just once for no apparent reason (needs 2m 'social distancing'). \n18:00 your temperature has gone up (first noticeable indication?). \n06:00 your life sucks like it has never sucked before."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2bghf7
|
Why do a lot of little kids have freckles, but not that many adults?
|
Also, why are they more common with red headed people?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2bghf7/why_do_a_lot_of_little_kids_have_freckles_but_not/
|
{
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"Two theories about the prominence of freckles in children are as follows:\n\n1. Freckles, being triggered by exposure to sunlight, are more common due to more frequent exposure to the sun and outdoors play, coupled with less care for sunscreen. \n\n2. Freckles, being clusters of melanin, are more easily visible through the thinner skin of a child. On adults their presence becomes more subdued.\n\nAs for redheads, there is likely a genetic correlation to freckling; the amount of freckles is genetic and is related to the presence of the melanocortin-1 receptor MC1R gene variant."
]
}
|
[] |
[] |
[
[]
] |
|
xrgy5
|
what is r/circlejerk?
|
I figure this belongs here because it's popular culture (at least to redditors) because references to the page are made EVERYWHERE. I went on, and the only heads or tails I could make of it is that it is a place where people pretend to speak french and make up stories. Is this an accurate analysis?
**Edit:** Thank you!!!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/xrgy5/what_is_rcirclejerk/
|
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"It is a subreddit where they mock the rest of reddit. The more time you spend on Reddit the funnier /r/circlejerk becomes ",
"It's a kids game that could alternatively be called \"Who can agree the loudest!?\". The idea of the game is no matter how ridiculous something is (actually the more ridiculous the better) you have to agree really LOUDLY. There are no winners.\n",
"It is making fun of widespread and stupid or really immature/youngish opinions on Reddit. For example American anti-Americanism of the I-am-better-than-the-people-around-me-kind, the dumber kinds of atheism, the incredible wankery around science and so on. \n\nIt is basically a place to vent every time the Reddit Hivemind rustles your common sense and not being a narcissistic pseudointellectual prick jimmies."
]
}
|
[] |
[] |
[
[],
[],
[]
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|
69tm5a
|
How well did the the late Roman(Byzantine) emperors know their history?
|
For example, did Constantine XI know that the small empire he ruled had once been a Mediterranean spanning empire that was founded over 2000 years ago in Rome? I'm sure he knew that his empire had been way larger, controlling all of Grecce and Anatolia(and obviously Rome).
But did he know that Rome had once been a republic? Did he know about Carthage? Augustus? The fall of the west? I'm sure he knew about Constantine the great but other great emperors and statemen?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/69tm5a/how_well_did_the_the_late_romanbyzantine_emperors/
|
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"I can't speak as well to the last Byzantine emperors but its early and middle leadership certainly were aware of their past connections and history to the earlier \"Roman empire.\" This awareness, if nowhere else, is apparent in the Byzantines' own term for self-identification: Roman (the identification of \"Byzantine\" is attributed to Hieronymous Wolf in the 16th century).\n\nJustinian I (527-565 CE) was driven to recover, through the Byzantine Empire, the lost glory of the former Italian Roman Empire. Despite the proclaimed cause of his Gothic campaign (the assassination of Queen Amalasuntha), the 535-554 CE conflict -- in addition to his Vandalic campaign in North Africa -- was focused around reclaiming lost Roman territory. Unfortunately, while Justinian was successful in that expansion, in typical Byzantine fashion, those gains were quickly lost in a relatively short span within the ensuing generations.\n\nHeraclius I (610-641 CE) was a capable military general-turned-emperor from Carthage. He was certainly aware of his city's past history and affiliation with the previous Roman empire.\n\nLater, several major religious events would bring that past mutual history to the forefront and its breaking point. The Monothelistic and Iconoclastic Controversies (First and Second) of the seventh, eighth, and ninth centuries CE, surrounded theological ideologies on the nature and will of Christ, and the legitimacy of icons. These matters resulted in Byzantine conflicts with the Roman papacy and Italian peoples. Those conflicts brought that past relationship to the forefront, but stressed that lingering goodwill toward a social, political, and religious break. \n\nBy the time we get to later emperors and dynasties, such as the Macedonian from 867-1025/1056 CE (I recognize the end of the M. Renaissance as Basil II), Byzantine identity is something unique. Although they still consider themselves Roman, the Byzantines are now the product of over 700 years of cultural exchange and conflict: their state reflects the integration and opposition to multiple foreign peoples, including the Rus, Bulgarians, Greeks, Goths, Franks, Persians, Jews, and Arabs. Emperors have come and gone, some by peaceful means and others by assassination or civil war. Consistency in the empire, I've seen it argued, is held by a break between perceived reality and actual reality: the elevated idea of the imperial court, versus the dirty reality of its complicated leadership (See the 10th century Book of Ceremonies). \n\nThis shifting perspective is even more apparent during in-fighting among Byzantine leadership post-Manzikert (1071 CE) when several aristocratic families actively aligned with Turkic forces for their own gain. The Crusades serve as another example (1095-1291 CE), in that the Byzantines were not always aligned with the Papacy and Western Europe's crusaders. \n\nAlternatively, you should also consider the evolving state of Byzantine education and leadership over the centuries. Without going into too much detail, the seventh and eighth centuries CE can be considered rather fractious and tumultuous times. They are characterized by a shift in political leadership, away from educated scholars and toward former military commanders. This is as much a result of internal policies as the state's then-current military opposition and frequent engagement with Arab and Bulgarian forces. Internally, this period is recognized by a general decline in the empire's educational standards; public works within this time tend to drop off, to the detriment of the empire's previous standards and its citizenry. This decline is later corrected during the Macedonian Renaissance (867-1025 CE).\n\nIn short, the Byzantines (as we know them today) were certainly aware of their past history, as past glory and power were frequent points of reference in the empire's early years. However, the importance and value of that past history was subject to change over the 1123 years of the empire's run (starting from Constantinople's dedication in 330-1453 CE). Over the evolving course of its length, the empire was exposed to new ideas and peoples, and was subject to shifting demographics and political leadership. These changes repeatedly brought about policies and internal divisions which affected foreign policy, and often pitted it against past allies and affiliations. ",
"The Byzantines were always relatively interested in antiquity, and especially in Rome. They never \"forgot\" that they were, however theoretically/distantly, part of the Roman empire. I can't say for certain how much Constantine XI was interested in this, since he probably had more pressing concerns than ancient history. But the Palaiologoi *do* seem to have been very interested in their connections to pre-Fourth Crusade Byzantium, and in turn to Late Antique and even ancient Rome.\n\nFor example: the Souda is a relatively well-known Byzantine reference book, a kind of encyclopedia containing mostly interesting grammatical and historical trivia, originally compiled around the year 1000. (You can check out a pretty handy translation online [for free](_URL_0_); see the entries for e.g. [Augustus](_URL_1_), [Caesar](_URL_6_), [the Roman Empire](_URL_2_), etc. for what the Byzantines might have been interested in on these subjects.) Now, the Souda is written in Greek, and the Byzantines didn't know much (if any) Latin, but aside from the grammatical component of the entries (mostly, for example, words that appear only once in Homer/Sophocles/etc.) a great deal of the Souda's entries are on Roman history. There's certainly some Greek stuff, but not the kind of classical-interest stuff you'd get in a modern ancient history course: they've got a pretty substantial entry on [Alexander the Great](_URL_5_), but no single entry on \"Athens\" or \"Sparta.\" When they quote historians like Polybius or Plutarch, it's mostly for what they've got to say about Rome, and almost certainly about imperial Rome (since the Byzantines too recognized the importance of having an emperor). \n\nThe tenth century was a remarkable period for this sort of thing, so maybe the Souda is just a fluke. But the Palaiologoi, at least two hundred years after the Souda was compiled, made tons of copies of it: [Pinakes](_URL_4_) lists some 53 manuscripts copied between 1204 and 1500. Some of these are [pretty fine copies](_URL_7_), if not terribly embellished, but even a plain hand-written copy of an encyclopedia represents a tremendous amount of time and work. The manuscript I linked here is dated to 1402, so it's probably not originally meant for a western audience (as some of these, especially after 1453, may have been); this also means it was written when the empire was not necessarily in the best position, diplomatically or financially. Yet even while they're surrounded on all sides they're still copying books about the Roman past. Not all of the information they have about this past is accurate -- but at this point, the same is certainly true of the West. \n\nI'm not terribly knowledgeable about Palaiologan classical reception, but most of the scholarly reading on the Souda that I'm familiar with is a.) in Italian and/or b.) probably difficult to get to outside of an academic library. If you can get to it, I recommend Barry Baldwin, \"Aspects of the Souda,\" *Byzantion: Revue Internationale des Études Byzantines* 76 (2006): 11-31. The [S\\(o\\)uda On Line](_URL_0_) site also contains some general information about the work, the most relevant of which you can find [here](_URL_0_about.shtml) (under \"The Raw Material\")."
]
}
|
[] |
[] |
[
[],
[
"http://www.stoa.org/sol/",
"http://www.stoa.org/sol-entries/alpha/4413",
"http://www.stoa.org/sol-entries/rho/246",
"http://www.stoa.org/sol/about.shtml",
"http://pinakes.irht.cnrs.fr/notices/oeuvre/12664/",
"http://www.stoa.org/sol-entries/alpha/1121",
"http://www.stoa.org/sol-entries/kappa/1199",
"http://www.bl.uk/manuscripts/Viewer.aspx?ref=add_ms_11893_f001r"
]
] |
|
129pv6
|
Can cancer cells potentially mutate to virulent forms?
|
Student with biology as major here. I'm currently studying for my microbiology exam, and I'm going through cancer and how mutations can make cells progress towards various forms of of the decease.
So this thought hits me. If cancer mutates to behave largely independent of the host organism through uncontrolled mitosis, can cancer cells potentially mutate to become virulent and infect other people, and even worse; without their bodies recognizing the cancer cells as foreign objects?
|
askscience
|
http://www.reddit.com/r/askscience/comments/129pv6/can_cancer_cells_potentially_mutate_to_virulent/
|
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"[Yes, cancer can become virulent(potential NSFW GORE)](_URL_0_), and it is the main reason Tasmanian devils are endangered. ",
"You are looking for [Clonally Transmissable Cancers](_URL_0_). Three types are known, one for Tasmanian devils, one for dogs, and one for Syrian golden hamsters. Additionally, one case is known in humans, where a cancer transferred to a surgeon through a cut.\n\nTasmanian devils have low genetic diversity, and Syrian golden hamsters in captivity all come from one single pregnant female, and the genetic similarity of members of these species probably makes it easier for these kind of cancers to spread. On the other hand, dogs have them too, perhaps implying that they could spread in humans as well, given the right mutations. Certainly it seems that some sort of body to body contact is necessary, given that the cells can't really survive \"loose\" in the environment.\n\nAll in all, an interesting topic, especially since, phylogenetically speaking, these diseases could essentially be considered single-celled parasitic mammal species."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Devil_facial_tumour_disease"
],
[
"http://en.wikipedia.org/wiki/Transmissible_cancer"
]
] |
|
23ccyk
|
why aren't we sexually attracted to our siblings or parents?
|
I know some people are, but why doesn't the majority of people find their siblings or parents sexually attractive?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/23ccyk/eli5why_arent_we_sexually_attracted_to_our/
|
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"text": [
"[Westermarck effect](_URL_0_) - we're not attracted to thoe we grew up with.",
"Imo its more a cultural and societal thing because there have been plenty of cases of incest and lusting of or after family members. I think the average person is gonna take any of those feelings and bury them deep down though it's not gonna be something that a person would openly admit to.",
"I look exactly like my dad and let me tell you he is one handsome fellow.",
"It all comes down to evolution - we are attracted to the people we perceive to give us the best offspring. People we are related to share *too* mush DNA with us and therefore would not provide good offspring."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Westermarck_effect"
],
[],
[],
[]
] |
|
8xip0o
|
Did Nazi Germany get any tourism? If so, what countries visited? Were people who would be otherwise gassed (Jews, Blacks, homosexuals, etc) allowed there? Were they allowed to leave?
|
Reading The Stand by Stephen King, the antagonist Randall Flagg often compared to Hitler and he said something about the other society visiting (as a ruse) and it got me to this question.
Side note: Great book if you're into reading.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8xip0o/did_nazi_germany_get_any_tourism_if_so_what/
|
{
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"Having written on the topic of forreign tourism before, I'll reproduce that here as it may be of interest, although more can always be said.\n\nNazi-era Germany wasn't necessarily destination number one for foreigners looking to travel abroad, but that isn't to say it wasn't seeing any visitors, and during the 1930s, Germany wanted to encourage people to see it as a travel destination for both economic and propagandist reasons. the push came both from private, industry related organizations such as well as government related groups, one of the big ones being the Reichsbahnzentrale für den Deutschen Reiseverkehr (German Railroads Information Office, or RDV), which was one of the biggest initiatives for promotion of Germany as a vacation destination, which took up the vast majority of its advertisement focus. They ran 31 offices in 26 countries by 1938, and coordinated from its headquarters in Berlin. The aim of the RDV in its promotions was to serve state needs, not only bringing in foreign currency from visitors, but also attempting to create more positive images of Hitler's Germany for people, even if they were unable to follow through with the journeys the RDV was selling.\n\nThe image that the RDV projected was one heavily laced with propaganda. They billed Germany as a modern, attractive, cultural destination, but heavily played up \"*how Germany is going ahead: no unemployment, production at peak levels, social security, gigantic projects for industrial development, economic planning, organized efficiency, a dynamic will of pulling together – a happy, energetic people who gladly share their achievements with you*\" to quote one ad. The low cost of Germany as a destination was also a popular draw that the RDV played up, a favorable exchange rate for most foreign visitors allowing for the country to be billed as a good destination for those on a budget.\n\nTo focus on the USA, the RDV had an annual budget of 470,000 RM which were spent on initiatives such as newspaper advertisements, promotional films, and informational handouts for travel agencies, highlighting and promoting different destinations of interest in Germany and various events being held through the year that might draw people. They also did 'cultural' promotions with museums and schools. Prospective travelers could reach out to the RDV office and receive sample itineraries to help them plan their trip, as well as informational packets to guide them on various things they would need to be aware of. Although it of course doesn't mean every single person ended up going through with a trip, the RDV was receiving anywhere from 65,000 to 150,000 such inquiries a year during the 1930s, which can help give some idea of the level of interest for travel to Germany from the USA during the decade. The campaign was evidently successful too, and authorities recorded that from 1934 to 1937, numbers of American tourists had doubled. Interestingly, even after war broke out in 1939, the RDV continued to operate in the US, working to signal German confidence in a speedy victory and resumption of travel in the near future, nothing more than thinly veiled propaganda at that point in time - to the ire of many - but it wouldn't be closed down by the US until June of 1941 (offices in neutral and Axis countries would remain open beyond that point).\n\nAll in all, the push for foreign tourists seems to have been a successful one. from 1933 to 1935, German authorities claimed that foreign tourism increased 260 percent. Although as with any numbers from the Nazi government, it must be taken with a grain of salt as to its precise accuracy, the numbers certainly were going up. To quote from Semmens' \"Seeing Hitler's Germany\", from which I've been drawing on here, she provides a brief overview of the numbers for the middle of the decade:\n\n > The Olympic Games marked a banner year in international tourism and Berlin was not the only city to benefit. That summer, 1.2 million foreigners, about 15 per cent of all registered visitors, arrived in Germany, an increase of 55 per cent over the summer of 1935. Thuringia alone witnessed a 61.3 per cent rise in visitors from abroad.77 But the Olympic year merely presaged what was to come. Berlin welcomed almost 56,000 more foreigners in 1937 than it had in 1936.\n\nLooking at the entire initiative, it seems to have been on the whole successful in the goals Germany wanted. While the rising amount of tourist traffic to Germany should be understood as part of the larger international picture which \"saw a continual increase in leisure travel after the Great War\", the initiatives by the German government specifically played an undoubted part in seeing the country, specifically, chosen as a destination out of other options. And although not every visitor of course was swayed and instead left with sour impressions of the Nazi movement and the changes it had wrought, most visitors seem to have left the country for home with thoroughly positive impressions of what they had seen, extolling the \"pleasant normality\", a small victory for the propagandist aims of the tourist initiative as a whole, although of course hardly enough to sway international opinion in the end.\n\nAll cited from \"Seeing Hitler's Germany: Tourism in the Third Reich\" by Kristin Semmens. Specifically see Ch. 6 \"International Tourism\" pp. 129-153",
"You might be interested in reading [A Time Of Gifts](_URL_0_), by Patrick Leigh Fermor. It's a primary source memoir written by a young Brit who, after (if memory serves, it's been a minute since I read this) dropping out of Oxford, decides on a romantic whim to walk on foot all the way through Europe -- getting to the Continent by boat, of course -- to Istanbul. In, like, 1934. He spends a lot of the book in Nazi Germany, and almost all of his journey is through areas that would soon be Nazi-occupied. Along the way, he mostly either stays with affluent European families via his social connections or falls upon the locals in whatever village he's passing through. He meets lots of Nazi sympathizers and many people who are otherwise not political but, surely, within a few years, would have been swept into the Nazi orbit. (I haven't read up on his more significant acquaintances and what specifically happened to them in the war.)\n\nOf interest here is the fact that Fermor was not in any way an official guest of high ranking Nazi officials. The nation of Germany wouldn't have cared that he was a tourist there any more than 2018 Germany would care if you took one of those Viking River Cruises up the Rhine. He was just a guy who had a harebrained scheme and ended up in Nazi Germany. The UK and Germany weren't enemies yet, and while I'm sure his friends and family back home thought the whole thing was a ridiculous fantasy, there was no real bar to him doing this. As he walks from village to village through Germany, he is greeted warmly by locals and soon finds himself basically on the German \"tourist trail\", walking the same paths that all kinds of tourists have taken for decades before him. Nobody thinks it is unusual or a bad thing that he is there.\n\nIt should be noted that (as far as anyone knows?) this wasn't espionage or any kind of \"the other side visiting as a ruse\". He was just some guy. He was also white, British, Christian, and I believe he had studied German in school and had connections on the continent. This was also, again, before the war per se and definitely before the \"Final Solution\" or anything like that.\n\nEDIT: I feel I should also stress that Fermor was not, himself, a Nazi sympathizer and ended up fighting on the Allied side during the war. He also famously lived undercover for 2 years as part of the Cretan anti-fascist resistance and was instrumental in the capture of an important Nazi commander. In part using knowledge that he had gathered on his travels before the war."
]
}
|
[] |
[] |
[
[],
[
"https://www.amazon.com/Time-Gifts-Constantinople-Holland-Classics/dp/1590171659"
]
] |
|
1axomk
|
How did some species (i.e, humans) come to require proteins that they could not produce themselves?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1axomk/how_did_some_species_ie_humans_come_to_require/
|
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"I think what you meant to ask is why some species have come to lose the ability to synthesize certain amino acids - not proteins. Amino acids are the building blocks of proteins. In the process of digestion, any protein that you consume are actually decomposed into the amino acid building blocks, which are then absorbed by your body for whatever use.\n\nNow, as for why species have come to lose the ability to produce certain amino acids? Well, that's kind of a tricky question to answer. The really unsatisfactory answer is that at some point in our past, our diet had these amino acids in sufficiently consistent and large enough supply that when our genes that conferred us the ability to synthesize the amino acids were damaged or lost, the impact on our fitness was minor enough that it wasn't really a problem.",
"_URL_0_\n\nThis covers a lot of it. Some highlights.\n\nSpecialization emerged early in evolution when there was little selective pressure to make certain amino acids for certain organisms.\n\nTryptophan is very expensive biochemically to make, so that may explain why it is essential.",
"Spin off question: If humans were able to produce all amino acids required for the proteins that we need, what's stopping us from consuming pure calories and water? What else does the body need?\n\nEdit: I just realized there are some minerals we need like Calcium and Potassium. What if we took a multivitamin+multimineral as well?"
]
}
|
[] |
[] |
[
[],
[
"http://www.nature.com/scitable/topicpage/an-evolutionary-perspective-on-amino-acids-14568445"
],
[]
] |
||
43fiu6
|
What was the relationship between knight and horse?
|
I know this is a huge question that can't be possibly answers to a certainty but I'm curious as to how knights treated there horses, which were more likely than not, invaluable. Did they form a close relationship with them the way is today feel with our dogs? Or was it more of a master servant relationship?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/43fiu6/what_was_the_relationship_between_knight_and_horse/
|
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"I don't have an answer to knights of the medieval period in particular but the training and relationship between horse and trooper in the Napoleonic Wars and beyond is essentially that first and foremost that it was a primary mode of transport and fighting platform. In a sort of quid pro quo scenario, a trooper that looked after his horse and that his horse was attuned to could make your life on the trail/campaign much easier. A horse soldier without his horse is not well equipped and trained for life on the march, although towards the end of the Napoleonic Wars, the Grand Armee had some dismounted dragoon units (distinct from what the British called dragoons, which was every mounted unit in existence). A late as the Australian campaign in the Middle East in WW1, the reports of troopers loving their mounts and the great care and dedication which the men made for them are as common as accounts of general staff aides riding horses to death to bring news and/or messages between generals. \n\nCertainly, a lot of famous generals and marshals had horses which they loved; the Duke of Wellington had a horse which he rode throughout his Peninsular Campaign and Waterloo (a half Arab named Copenhagen) and the Emperor Napoleon had an Arab which he rode from his Egyptian campaigns all the way to Waterloo. Both of these men had a great love of their horse, I guess very much in a way you have a favourite dog but I wouldn't like the speculate what sort of affection they had to their mounts - they certainly loved them, after a fashion. The hunting dogs of Louis XIV of France were greatly loved as well - there are paints and bronzes of these guys all over Fountainbleu. \n\nAll in all, the conclusion I would draw is that a knight would love and care for his horse so long as it was able to fulfill his or her obligation as either a war horse or palfrey, for which either were expensive commodities which affected a knight's ability to fight on campaign much more than, say, the quality of his arms and armour but less than his retinue of sergeants and 'staff' for want of a better term. \n\nSources:\n\nAustralians at War (?) - Unknown (pre 1950), Monash University Library Collections **This is not a properly cited source, I'm sorry! It was missing pages and water damaged to boot!**\n\nCaptain Coignet - Jean-Roche Coignet (Published Leonare 2007)\n\nSwords around a Throne - J R Elting (1988)\n\nBreaking and Riding: With Military Commentary - James Fillis (2005)\n\nInteresting read: _URL_0_"
]
}
|
[] |
[] |
[
[
"https://www.awm.gov.au/wartime/44/page54_bou/"
]
] |
|
277dt0
|
swift, apple´s new programming language
|
Is it helping? Or is another programming language just adding a new layer of confusion and complexity?
What can it actually do?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/277dt0/eli5swift_apples_new_programming_language/
|
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"While I can't talk specifically about Swift, seeing as I've not read much about it, I can tell you something about programming languages: new languages constantly evolve. Often as \"better versions\" of older ones. Each programming language has a different use and a different feeling to it. Certain things are going to be easier, others are going to be more complex. One of the core differences between languages is how much you have to micromanage and how close the language is to the machine - the closer it gets, the more micromanagement and in-depth knowledge is normally required, meaning that more time has to be put in.",
"It was just announced. This is the first that anyone outside of Apple's heard of it. Ask again in a week or a month if you want to get some unbiased opinions on how good it really is.\n\nUltimately, it can only help so much. Programming complex programs is complex. No matter how much easier it becomes to express the complexities, they won't go away. If you're making a fighting game with 500 different moves, somebody still has to program them and decide how they interact - no language can make that go away."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1mjs37
|
how are large games abled to be rendered?
|
Im a PC gamer and I was wondering how different games are rendered. Why is it that I can get ~100fps in call of duty or source games (games with small maps) but other games (like skyrim or other huge maps) able to be rendered with the same fps? Basically I heard of a new game coming out with endless generation and was wondering how it would work. Minecraft is endless but that maintains fps by rendering the map in different chunks and you can change how far it is rendered. I was wondering how a graphically entense game would be rendered endlessly and how games like skyrim or GTA5 are capable of rendering such huge places with great fps? That then led me to wonder if games like skyrim are able to load huge areas with good fps why are smaller maps and games not able to load small areas with alot better fps?
Edit: So its all based on the games specific engine and how it does things? For games like skyrim or large maps it has ways of making things farther away less taxing to render, and thus games with smaller maps are just as taxing due to rendering alot more polygons at higher resolutions? I guess its a little bit too over my head to truly explain like im five. But i thankyou for answering.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1mjs37/eli5_how_are_large_games_abled_to_be_rendered/
|
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"Generally there are a few methods:\n\n* Intelligent clipping. You only draw the polygons that might be visible.\n\n* Variable Level of Detail. As objects become more distant, they get drawn more simply. A building might be very intricate up close, but at a distance might be rendered as just a single rectangle.\n\n* Fog. This one is cheesy, but it's been used in a few games. You draw a stack of semitransparent polygons at fixed intervals out from the camera, creating the effect of a uniform fog. Then you just stop rendering stuff at a distance where it would barely be visible anyway.",
"Not at expert in the field, just a fellow gamer, who blundered through the 64 fog...hopefully someone more qualified can answer better...\n\nAnyways, the basic idea as I understand it, is that the further away something is in a video game, the less detail it is rendered in. In Skyrim, for example, the Throat of the World is probably made of only a relative handful of polygons as you gaze upon it from Whiterun, but conversely, so is Whitefun when looking upon it from the Throat. The game and your PC can only handle so many polygons and textures, but things far away are rendered in less detail, and so, until you get close to them, only use a few polygons, and low-resolution textures. \n\nIn some games and with some graphical options checked, you can actually see it update as you close, as in \"pop in\". Objects in the world will jump from a low-quality to a high-quality. This was more noticeable in older systems, and a high-end PC can hide it pretty well."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1nqc1q
|
Why didn't every independent medieval ruler declare himself a king?
|
Many rulers, like those of Cyprus, Naples, or the German states, did declare themselves kings, but still many rulers were content with living their lives as counts or dukes.
Why was this?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1nqc1q/why_didnt_every_independent_medieval_ruler/
|
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"Do you have specific examples?",
"One does not just become a king. In almost all circumstances a higher power created kings. In the older kingdoms that trace back to antiquity that 'higher power' is often claimed to be descent from a god or the ancestral founders of a people. Just assuming the title of king back then was the equivalent of an American citizen just declaring themselves President. Even if that person has a lot of power everyone knows its not legitimate. \n\nMost people in the Middle Ages would look to the Bible for the example of how a new king is chosen for a people or area without one. God sent the Prophet Samuel to anoint Saul and only that made him king. They would also note that God and Samuel could also remove the king which they did when they anointed David in Saul's place. In the Middle Ages the Pope would be the equivalent representative from God as a Prophet. The power to be king as opposed to a mere lord of some time flowed from the religious authority ie the Pope. The other possible source was from the Emperor (Roman or Holy Roman as the case may be). Now was it always on the up and up? No. In the case of Sicily there were definite shenanigans. Dukes of Sicily playing Popes against Antipopes and Popes against Emperors until someone was desperate enough to make the Duke a King in return for aid. But the Duke still had to get that outside acknowledgement before crowning himself however forced (and contrived) it might have been or he would have been looked at as illegitimately assuming a title.\n\nThe rulers above did not just declare themselves king:\n\n * The King of Naples was previously the King of Sicily who lost Sicily in a rebellion. The Kingdom of Sicily was granted its crown by the Pope in return for its assistance against the HRE.\n\n * Cyprus was created a kingdom after it was conquered by Richard the Lionheart of England. It was given to a former King of Jerusalem who was Richard's vassal as a consolation prize for being ousted from Jerusalem and to rid Richard of a problem territory. It was done with the consent of the Holy Roman Emperor Henry VI. The King of England has long considered itself as a lord over lesser kings, notably Scotland so this was not a case of a king creating an equal but a king creating a lesser king.\n\n * You will have to be more specific on German states but I'm sure if you do the research you will find that in almost all circumstances a higher power (Pope or Emperor) raised a lesser noble with a lot of power to the title of King.\n\n",
"They *could* declare themselves kings - many minor Irish rulers did, for example - but this was largely useless if their royal title wasn't internationally recognized by friends and foes alike. To get that recognition, you usually needed to get that title from a superior authority, which in medieval European reality meant either the pope or (western or eastern) Roman emperor. \n\nIt's not that the rulers were* content* to remain dukes or counts. It's just that they didn't have money/prestige/diplomatic pull/high-ranked friends to get a higher title.\n\nIn case of Poland, for example, the early Piast rulers used the title of Ksiaze (Prince/Duke, in Slavic tradition it's difficult to separate this two terms)\n\nIt is thought that Boleslaw I might have obtained the emperor's Otto III consent to become a king during their meeting at Gniezno in 1000, but after Otto's death his successor fiercely opposed his attempts as HRE claimed sovereignty over Polish lands (Boleslaw's father Mieszko I was considered and behaved like an imperial vassal at times).\n\nIn the end, Boleslaw I didn't become a king until 1025 - a few months before his death - despite being an extremely powerful ruler, capable of occupying Bohemia, capturing Kiev and forcing territorial concessions on HRE emperor.\n\nLater on, Polish state collapsed and the royal title was lost. Boleslaw II was able to regain it in 1076, thanks to his status as an ally to the pope in his conflict with the emperor. However, few years later he was overthrown and his brother and successor Wladyslaw Herman sent his insignia to Germany in order to get in emperor's good grace.\n\nInterestingly, few centuries later it was Poland that was blocking another country's attempts at becoming a kingdom. In the early 1400s, emperor Sigismund of Luxembourg sent a royal crown to the Grand Prince Vytautas (Witold) of Lithuania, but Poles stopped them on their way.\n\nIt's my observation, by the way, that during the 13th century it become somehow easier to become a king. The rulers of Lithuania, Albania and Galich all received royal crowns from the Papacy - it seems it was an award for supporting Catholicism in their respective countries. In case of Poland, Przemysl II become a king in 1295, despite ruling only two of the Polish provinces and being significantly weaker - both internally and externally - than several of his ancestors who were merely dukes/princes."
]
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|
[] |
[] |
[
[],
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|
7sk9lx
|
why aren’t more major electronics companies making video game consoles?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7sk9lx/eli5_why_arent_more_major_electronics_companies/
|
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"The cost is way too high for the profits available. You have to invest huge sums in games and then make profit from selling hardware at very low margins. It's more a question of why anybody is still making consoles.",
"There is almost zero profit in consoles. They are loss leaders. For a while, Microsoft was losing $100 for every XBox sold, but they try to make it back with games. So unless you own a crapload of game studios, it's not worth it to make the hardware.",
"For a console to be successful, it has to have a large following, and a lot of development behind it. That’s hard to create from nothing. Also, most people only have room in their lives and budgets to devote to one console. A customer that has put a lot of $$$ into one console usually can’t afford to do the same with another, and has less incentive to do so. What you see (PS, Xbox, Nintendo) are the three current exceptions to the rule that creating a console is damn difficult.\n\nIt’s a lot like smartphones and why they quickly converged on just two major players. It’s no coincidence that both were created by huge corporations with a solid vision and a crapload of resources to risk on the venture. ",
"First, creating a console takes a lot of time and money. If they don't sell enough, they lose lots of money.\n\nThey have to compete with other consoles that exist. Are you going to buy a PlayStation, an XBox, or a Huawei JoyMech? \n\nAll the companies making games? You're saying they need to translate games even more. It already takes time and money to translate a game from Windolish to Xboxese and PlayStationian. Now they have to translate it into JoyMechan as well?\n\n OUYA tried doing this halfway. It used a language that was already out there (Android) and simply made things show bigger on a TV and use a consult controller. \n\nIt still failed, badly. Barely lasted 3 years. The problem? \n\nNobody wanted to make games for this new thing. Nobody wanted to make games in a new language. Not enough people wanted to buy the new thing instead of another Xbox. \n\nAnd there wasn't enough people using it to make high enough sales and make money."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
5cxg3p
|
why is the ability to ride a bike something you can't lose once you gain it
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5cxg3p/eli5_why_is_the_ability_to_ride_a_bike_something/
|
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"Muscle memory. You don't have to mentally remember anything because your muscles remember how to preform actions they've repeated over and over. Another example is that I learned how to solve a Rubik's cube in 6th grade by memorizing 10 or so algorithms but now I couldn't tell you what they are or even write them out. I can still solve a Rubik's cube however because the movements are so engrained in my muscles. ",
"If you learn to ride a bicycle with reversed steering, you can no longer ride a bike with normal steering until you learn again. The Backwards Brain Bicycle - Smarter Every Day _URL_0_ From /u/MrPennywhistle I believe.",
"In terms of psychology your brain has sensory memory, short term memory and long term memory. Now long term memory can be broken down into two categories: explicit and implicit. Implicit has 4 categories; 1 of which is procedural. This is where all motor skills like typing on a keyboard, riding a bike, swimming, etc go and are stored for vast amounts of time. This is because your brain has remembered the blue prints for how to execute those activities and has placed them your long term memory",
"Bikes are governed by a strange law...\n\n\"Push Right and Lean Right to Go Right\". (and left, left, left).\n\nThat is, if you push the _RIGHT_ handle of the handle-bar forward the wheel will point _LEFT_, this just looks and feels wrong when you start. You are \"steering left\" to \"go right\".\n\nIndeed if you hold a bike upright and walk it, you'll \"push left\" forward to right. But not when you are riding.\n\nThis rule is counter-intuitive because the static analysis and any vehicle that cannot tilt works \"the other way\", from a trike to a wagon to a car, you steer right, to point the wheel right, to go right.\n\nNow if you pay lots of attention to riding, you'll discover that you \"push right to lean right\" because by steering to the wheel to the left, you move the center of gravity to the right of the center of support, or more correctly you move the bike \"out from under you\" to make the leaning easier.\n\nAnd if you stop pushing right, the bike will come back under you and you'll be going straight again. This self-correction is why you can shove a bike out of a moving truck or take your hands off the bar, and it will stay upright as long as it's still moving.\n\nSo anyway...\n\nOnce you learn this odd rule it has it's own path in your brain. If you haven't been on a bike in many years you might take a few moments to recall this process. But the sensations of falling over and the self-correcting nature of the bike will quickly remind you of how it works ... or you fall down ... and your brain _hates_ falling off a bike, so it's very motivated to re-learn and reinforce the old understanding.\n\nSo between threat of injury and very unique system, it's the kind of thing your body and brain are designed to remember.\n\n(EDIT :: Wikipedia on \"[Countersteering](_URL_0_)\")",
"It's because you don't actually learn to ride a bike. You just overcome the irrational fear of the bike falling and commit to it. It's like learning to jump off the high diving board. Not a skill just a psychological barrier. Something like an instrument requires extensive muscle memory and general memorisation."
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=MFzDaBzBlL0"
],
[],
[
"https://en.wikipedia.org/wiki/Countersteering"
],
[]
] |
||
4qs8um
|
Was there ever any protest or opposition to mandatory military service in ancient Greece and Rome?
|
Thank you!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4qs8um/was_there_ever_any_protest_or_opposition_to/
|
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"Nothing as dramatic as burning draft cards. Anyway, those people wouldn't have histories that survive. We do get a couple hints though.\n\nI'm assuming you aren't referring to mutinies - these are often not objections to service in general, but rather a way of bullying the state into giving the soldiers a better deal.\n\nThe big one is entirely unattested. It's a bit of a hike to get there, so strap in.\n\nThe standard narrative of the 2nd century leading up to the crises of the Late Republic is usually framed around the Land Crisis and the Gracchan reforms. All the sources agree on the basics of the story: Ti. Gracchus got concerned with 1) the mass of urban poor, 2) the proliferation of slave labor inside Italy, 3) the lack of men that met the property qualification to serve in the army. Gracchus proposed to solve this by distributing publicly owned property, which Rome rented to wealthy men to farm (with slave labor) as a source of state revenue, to the urban poor, so that they would both reduce the need for slave labor on the big farms (latifundia) AND provide a new body of men of sufficient wealth to participate in the army. I'm going to skip over the the causes of this problem and success or failure of this project and it's long term effects for this question, but lots of us have written about it elsewhere.\n\nThat is the traditional narrative. All the sources agree. It seems to be entirely wrong.\n\nRosenstein recently wrote a book* Rome at War* (here's a [review](_URL_0_)) that argues that there was no land crisis. There is no archaeological evidence of latifundia in Italy, or dissolution small farms, or proliferation of slaves. The sources are entirely wrong. So what did Gracchus think he was doing? He was responding to something, right? He wasn't manufacturing a crisis he died trying to fix out of whole cloth. Rosenstein suggests there WAS a dearth of soldiers, but not because of the property qualification. Rome's major engagement at this time was in Spain, which was a long, messy slog without much by way of loot. People just didn't want to go. They didn't show up when the call for soldiers went out, leaving the army understaffed.\n\nI have a suspicion that this (whether right or wrong) is partly the product of a scholar who lived through the problems with the draft the US experienced in Viet Nam; if nothing else it might have inspired Rosenstein to look for another reason for the dearth of soldiers. We'll see in a generation or so how that works out.\n\nThere are a couple of other incidents. \n\nAfter Punic 2, there was reluctance on the part of some centurions to serve in Macedonian 3. [Livy gives the account at 42.32](_URL_1_). Some people were being enlisted with a lesser rank than they held in P2, and the case was tried in the assembly. This isn't strictly speaking a refusal to serve, but rather service with conditions. Livy says the movement fell apart when they were shamed by another potential centurion.\n\nThe move towards paid professional armies might also be seen to follow this general line of protest. Scipio Aemilianus led an army largely of his clients to Spain. \n\nThere is somewhere a reference to the veterans of Scipio Africanus' African expedition being exempt from service in one of the wars following P2, but I can't find it at the moment. If I dig it up I'll add it."
]
}
|
[] |
[] |
[
[
"http://bmcr.brynmawr.edu/2004/2004-07-56.html",
"http://mcadams.posc.mu.edu/txt/ah/Livy/Livy42.html"
]
] |
|
2i01og
|
Will the first Quantum computer disrupt worldwide encryption and security?
|
Let's say this Quantum Computer just came out of the factory floor, and not-so-much-ethical individuals just started it up. Can it collect data - quickly - and start decryption before we can update all other encryption protocols and spread them?
I guess my question could be, also: "Will Quantum Computer generate a severe destabilization in worldwide encryption while we physically can't update system-wide encryption?"
|
askscience
|
http://www.reddit.com/r/askscience/comments/2i01og/will_the_first_quantum_computer_disrupt_worldwide/
|
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"text": [
"It's going to be a long slow process from first proof-of-concept prototypes (which we've seen), to prototypes that work reliably, to prototypes that have an actually useful capacity, to demonstrations of breaking weak crypto as another proof-of-concept, then finally something usable in a lab, then the NSA getting one and not able to use it all the time, to finally being commercially available someday.\n\nThe point is that there will be plenty of time for cryptographers to watch the technology develop and to respond. When big enough and reliable enough quantum computers become a reality, they will be able to instantly break today's asymmetric ciphers and significantly weaken (but not break) the symmetric ciphers. That may be a cause of concern for anyone worried about recorded communications, but by that time I imagine post-quantum cryptography research will have settled on some usable alternatives that can hold up.\n\nIt's an uncomfortable fact of most cryptography algorithms that they are not mathematically proven to be secure, it's just that after pounding on it for a long time they haven't found a way to break them. Probably that will happen again with post-quantum crypto. A cryptographer will say \"well I think this holds up against quantum computers, but I'm not sure, can you break it?\" And if no one does for a few years they'll say ok, that's good enough to use for now."
]
}
|
[] |
[] |
[
[]
] |
|
5vrc53
|
why does some scientists/countries still want to go on the moon ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5vrc53/eli5_why_does_some_scientistscountries_still_want/
|
{
"a_id": [
"de46h4c",
"de47303"
],
"score": [
6,
4
],
"text": [
"The moon is the closest large object to earth in space, so going to the moon allows us to develop and test a lot of technology related to landing on and moving around on solid, non-earth objects. Mars would be better to colonize for several reasons (atmosphere, temperature, soil, similar hours in a day, etc.), but we don't have the technology to set up a space colony yet and the moon is a much closer place to do testing.",
"The single largest reason is that it has a lower \"Delta V\" than Earth. That's just a way of saying that since the escape velocity on Earth is about four times higher than the Moon, it costs a lot more fuel to lift the same load out of Earth's gravity well than the Moon's.* If we're serious about doing things in space, and not just LEO, we're going to need to address the high Dv required to leave Earth. Fuel is *expensive* in every sense, because the essential problem of rocketry is that you have to lift your own fuel. Therefore fuel savings become a massive proposition, defining what kind of loads you can affordably send into LEO or further. \n\nThe reason why people look at the moon, is that it's a compromise between a pure space station, and a colony. You can reap the benefits of having a *little* gravity, while still having close access to freefall and vacuum. As with Mars, shielding from radiation would be accomplished by tunneling, and there might be something useful for fuel conversion there as well. It doesn't present all of the advantages of a space station or a bubble-formed asteroid colony, but it has the advantage of being something we actually could conceivably make soon.\n\nThe problems are numerous though, and while the Moon has a much lower gravity than Earth, it's still a problem. \n\n*Actually Dv is just \"Change in velocity\" and is shorthand for all of the acceleration you'll need for the whole mission, most of which is going to be a result of escaping from Earth's gravity well. Obvious Dv is a function of the gravity well you're in, and obvious how much you need to accelerate defines your fuel budget. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
2kn286
|
why do subreddits need mods to control posts? doesn't the voting system show what people actually want, whether it's shitty or not?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2kn286/eli5why_do_subreddits_need_mods_to_control_posts/
|
{
"a_id": [
"clmvdlj",
"clmwlxj"
],
"score": [
3,
2
],
"text": [
"If you have someone being abusive and harassing, simply down voting won't remove it from existing.",
"Hi! There are a LOT of things that really are better off not being seen by anyone. For example, sometimes there are accounts created solely to post spam everywhere possible. Other times, there's a network of accounts created by one or a group of people who go around trying to further some agenda (recently there was one such group posting questions and comments here about Jewish people drinking the blood of babies). There aren't enough admins to control all this. \n\nSometimes there's a thing that's popular enough for it to get upvoted to the level where it's seen by lots of people, while still spreading negativity and being unliked by many, like \"people who don't spay or neuter their pets should be banned from owning them\" or something. That's an extreme example, but I hope it gets the point across. \n\nAlso, if that were the case, all subreddits would be pretty much the same and that's no fun. \n\nSorry, I do have to remove your post, because rules and rules. /r/Askreddit, or another \"ask\" subreddit would also be a good place to post this. \n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
1hlb7a
|
why do royal families of defunct monarchies still exist?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hlb7a/eli5_why_do_royal_families_of_defunct_monarchies/
|
{
"a_id": [
"cavg3ao"
],
"score": [
2
],
"text": [
"Even if they came with no money or lands, titles can still give you an edge. "
]
}
|
[] |
[] |
[
[]
] |
||
1af64u
|
We saw that bionic eyes can be a success. Could we make them better?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1af64u/we_saw_that_bionic_eyes_can_be_a_success_could_we/
|
{
"a_id": [
"c8wvx6f"
],
"score": [
2
],
"text": [
" > Could we modify such a bionic eye so that a person could see beyond the visible spectrum (..., radio, IR, UV, X-ray, Gamma, ...)?\n\nYes. Current high quality CMOS sensors in cameras already do this. They need filters and coatings to keep them seeing the visible spectrum instead of IR and UV.\n\nAs far as X-Ray and Gamma that's a bit difficult since you need an emitter source and you also get cancer.\n\n > If yes, what kind of limiting factors would we run into?\n\nThe eye is still better than any camera sensor out there but the tech still has room to improve. Hold onto your pants.\n\n > If such a thing is possible, why can't we expand into other types of sensors, such as being able to feel (much more sensitively anyway), the strength of an electromagnetic field rather than it's frequency?\n\nInterfacing directly with the optic nerve especially in the resolution and bandwidth required is not possible yet."
]
}
|
[] |
[] |
[
[]
] |
||
2ojmc7
|
how come space probes that travel to distant planets not collide with the smaller objects in space?
|
All these objects are travelling at insanely fast velocities right? And there are thousands, if not millions of asteroids between Mars and Jupiter, right? How come the space probes never collide with even the smallest of particles?
If they do - shouldn't they face a lot of damage, owing to their high relative velocities?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ojmc7/eli5_how_come_space_probes_that_travel_to_distant/
|
{
"a_id": [
"cmnqh9h",
"cmnqhg8",
"cmnqhgo",
"cmnqhqz",
"cmnrcd7"
],
"score": [
7,
2,
2,
3,
3
],
"text": [
"Asteroid belts are nothing like in the movies. They are mostly empty space. Chances of getting hit are incredibly small. \n\nIt's like spreading millions of ants across a Sahara desert and stepping on one. ",
"Yes: Collisions in space are pretty deadly.\n\nNo: Despite it looking so, the asteroids are quite a good distance apart from each other. Space is massive, your chance of collision is actually very slim.",
"Yes there are a lot of objects between Mars and Jupiter, but they are really, REALLY far apart. It's like driving a car through a field and wondering why you aren't hitting any trees.",
"Space is really really big, and asteroids are really really far apart. The average distance between asteroids in the asteroid belt is about 600,000 miles.",
"It is true that other people wrote - that it's not easy to hit something large because things are far apart in space. However, most probes and satellites are equipped with special multilayer honeycomb core protective shielding to give some protection from micro-meteoroids.\n\nAlso probes are often rotating to use gyroscopic rigidity effect, so that even if they are struck with some meteor their trajectory will not be affected (at least not a lot)."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
9575nh
|
why can you feel capsaicin irritating your mouth, stomach, and butt but don't seem to feel anything when it's passing through your intestines?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9575nh/eli5_why_can_you_feel_capsaicin_irritating_your/
|
{
"a_id": [
"e3qmcdh",
"e3qxvy6"
],
"score": [
5,
3
],
"text": [
"Oh I've felt it. You try some good peppers or other high scovile oily food and you feel it working it's way through. It's not the same sensation, but you know it's there.\n\nAs for why you feel it less sit is because capsaicin triggers pain receptors and your main gut just doesn't have many pain receptors. Why would it? Skin, mouth, and anus have way more pain receptors because they are far more likely to come into contact with pain causing things.",
"Capsaicin is similar to an oil. Acid breaks it down, so once in your stomach the acid breaks it down. This stops it from irritating the mucus membrane in your stomach and intestines. This is why spicy foods are often served with a lime.\n\nCapsaicin is also fat soluble, which is why milk products also help with the heat."
]
}
|
[] |
[] |
[
[],
[]
] |
||
4jqyr2
|
Tuesday Trivia | Treasure Hunters
|
[Previous weeks' Tuesday Trivias and the complete upcoming schedule.](_URL_0_)
Today's trivia theme comes to us from /u/sunagainstgold!
To quote Sun's favorite start to undergrad history papers, *since time immemorial* humans have sought out treasure, whatever that word may mean to them. So **please share stories of humans looking for lost or secret things of great value**, from gold to historical objects to fountains of youth to scientific mysteries.
**Next week on Tuesday Trivia:** We'll be talking about different memorials and remembrances through history, from the tangible (like statues) to the intangible (like federal holidays).
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4jqyr2/tuesday_trivia_treasure_hunters/
|
{
"a_id": [
"d38sr6h",
"d398vur"
],
"score": [
12,
14
],
"text": [
"Heinrich Himmler, the infamous head of the SS, was a firm believer in the existence of ancient relics that had an immense power. Himmler believed that *Mjölnir*, the hammer of Thor, the god of thunder from Norse mythology, was an ancient electrical weapon. He believed that if this weapon was found by the Ahnenerbe (the Nazi German institution responsible for research and retrieval of history of the \"ancient Aryan race\") and its secrets uncovered, perhaps German scientists could turn ancient Norse knowledge into *Wunderwaffen*, being able to knock out tank divisions and entire armies.\n\nOur source for this belief is a letter that Himmler sent to Ahnenerbe, requesting a search for evidence of Thor's hammer. This letter was sent on May 28 1940 to the head of the Ahnenerbe, Walter Wüst:\n\n*Have the following researched: Find all places in the northern Germanic Aryan cultural world where an understanding of the lightning bolt, the thunderbolt, Thor's hammer, or the flying or thrown hammer exists, in addition to all the sculptures of the god depicted with a small hand axe emitting lightning. Please collect all of the pictorial, sculptural, written and mythological evidence of this. I am convinced that this is not based on natural thunder and lightning, but rather that it is an early, highly developed form of war weapon of our forefathers, which was only, of course, possessed by the Aesir, the gods, and that it implies an unheard of knowledge of electricity.*\n\nAs far as we know, nothing came out of this.",
"Here is one of my favorite stories.\n\nIn the 19th century a man named Heinrich Schliemann (1822-1890) decided to try to use the Iliad, which he had loved since he was a little boy, to find the location of Troy. Until then it was unclear if it was real or purely mythological. Schliemann, however, was convinced it was real and decided to critically study the Iliad for clues. In the 1860s, with Schliemann now in his 40s, he finally found what he had been searching for: The site of Troy.\n\nUnbeknownst to him he actually dug farther than he needed to and began to excavate an even older civilization that lay under the ruins of Troy. \n\nAmong his discoveries is the so-called \"Mask of Agamemnon\", which didn't actually belong to Agamemnon but still retains that name:\n_URL_0_\n\nHis discoveries helped spark a rush of new investigations into ancient Greek history, including what became known as Minoan (Crete) civilization.\n\nSource:\n\n-Leonard Cotrell: *The Bull of Minos*.\n\n[Yes, I keep citing this book. Yes, I really, really like it]"
]
}
|
[] |
[
"http://www.reddit.com/r/AskHistorians/wiki/features/trivia"
] |
[
[],
[
"http://imgur.com/i7OSS4v"
]
] |
|
7rt7zq
|
What really was Bushido?
|
I know this is a very broad question, considering the different eras involved, but I am having a hard time finding an answer to it so turned to reddit. Wikipedia (great source, I know) seems to draw mostly from Bushido—the Soul of Japan, which I’ve heard is heavily romanticized. If anyone who knows about the subject could help, it would be much appreciated
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7rt7zq/what_really_was_bushido/
|
{
"a_id": [
"dszi56a"
],
"score": [
5
],
"text": [
"Not to discourage other answers but /u/bigbluepanda and /u/ParallelPain discuss Bushido in these answers from the FAQ\n\n_URL_1_\n\n_URL_0_\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4rte1l/were_samurai_generally_honorable/d54202b/",
"https://www.reddit.com/r/AskHistorians/comments/52sewz/was_the_way_of_bushido_ever_documented_in_a_book/"
]
] |
|
4bfv96
|
Why are far away galaxies redshifted, when they aren't actually traveling away from us, there's just more space there than there was before? Does light lose energy traveling through a vacuum?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4bfv96/why_are_far_away_galaxies_redshifted_when_they/
|
{
"a_id": [
"d18y684"
],
"score": [
8
],
"text": [
"Yes, the light loses energy by being stretched as the Universe expands while it travels."
]
}
|
[] |
[] |
[
[]
] |
||
1oa0n7
|
How much, if any, correspondence occurred between opposing leaders during wartime? Is there more correspondence nowadays, or has it decreased over time?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1oa0n7/how_much_if_any_correspondence_occurred_between/
|
{
"a_id": [
"ccq4qm3"
],
"score": [
15
],
"text": [
"The first thing I thought of when I read your question was the ['Willy-Nicky Telegrams'](_URL_0_), an increasingly desperate series of telegrams exchanged between cousins (hence the familiar way they address each other) Kaiser Wilhelm II and Tsar Nicolas II in the last days of July 1914 as Europe was dragged towards war.\n\nThough the correspondence abruptly ends with the declaration of war on Russia by Germany on August 1st and so doesn't fit within the parameters of your question, you (and anyone else who hasn't seen them) might still find these fascinating. \n\n\n\n\n\n\n\n\n\n"
]
}
|
[] |
[] |
[
[
"http://wwi.lib.byu.edu/index.php/The_Willy-Nicky_Telegrams"
]
] |
||
1f2wkr
|
Who was history's first recorded gay right's activist, in times of homophobia?
|
I realize that it was not always the taboo in society that it was in many places the last few centuries.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1f2wkr/who_was_historys_first_recorded_gay_rights/
|
{
"a_id": [
"ca6jsom"
],
"score": [
3
],
"text": [
"It depends on what you define as an \"activist.\"\n\nKeep in mind that homosexuality as a category of identification really dates back to the late nineteenth century, when sexologists began to classify and medicalize homosexuality. This is also when the first real \"movement\" for homosexual rights was launched. The movement really began in Germany. Karl Heinrich Ulrichs is the man credited with launching the movement. He \"came out\" (before \"coming out\" was a thing) to his family by letter and called himself a Uranian, the term he coined for homosexual. He then went on to write extensively about homosexuality in a series of essays. This, of course, was almost unthinkable in 1860s Germany, where homosexuality was against the law. By 1867, Ulrichs was fighting for the repeal of the anti-homosexual law.\n\nIn 1897, two years after Ulrich's death, Magnus Hirschfield--a sexologist and advocate for homosexual rights--started the Scientific-Humanitarian Committee in Germany, the first major homosexual rights organization. The major focus of the group was to push for the repeal of Paragraph 175, an anti-homosexual law passed in 1871. This is when the \"movement\" pioneered by Ulrichs became larger and more influential.\n\nThe (albeit small) movement in Germany spilled over into the United States in the early part of the twentieth century. Having been in the military, Henry Gerber traveled to Germany and witnessed the movement for homosexual rights in action. He brought the idea home and started the Society for Human Rights in 1924 in Chicago. It did not last long. After one of the members' wives found out about the organization, she reported it to the police, who promptly raided its headquarters and shut it down, arresting those involved. The headline the next day read \"Strange Sex Cult Exposed.\" No gay rights organization would exist again in the United States until Harry Hay founded the Mattachine Society in the 1940s.\n\nHopefully that answers your question. For more reading about this, I would recommend John Loughery's book The Other Side of Silence: Men's Lives and Gay Identities. It goes into detail about the American side. For more on Germany, Richard Plant's The Pink Triangle: The Nazi War Against Homosexuals gives a pretty good survey of the early German movement."
]
}
|
[] |
[] |
[
[]
] |
|
684kwn
|
how can a distiller like jack daniel's meet doubled demand within one year when their product takes 4 years to age?
|
A recent TIL said that an endorsement by frank sinatra led to jack daniels doubling its sales of the previous year (150,000-300,000). But how is this possible when the minimum a bottle of jack daniels is aged is 4 years?
Post in question:_URL_0_
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/684kwn/eli5_how_can_a_distiller_like_jack_daniels_meet/
|
{
"a_id": [
"dgvmcxf",
"dgvnf7s",
"dgwgtkw"
],
"score": [
7,
14,
2
],
"text": [
"the article says the distillery was already almost 100 years old, so they probably already had enough stock to be able to sell 300,000 units",
"Jack Daniels complies with \"straight bourbon\" classification, which requires a minimum of two years in barrels. It's a blended whiskey, meaning that some of it may be older, and that blend can be varied. The company doesn't go in to exact details about blends and aging. ",
"Once whiskey is in a bottle is stops aging. So a 4 year old blend of jack is very similar to any other bottle of jack daniels. They can have a massive surplus. Aging only counts when it is in the barrel. \n\nA lot of fancy high demand whiskeys are hard to find in stock even for bars. Yamazaki 18 year old whisky is very hard to have in stock. I would order it for months on end and then get it and sell out in a week. At $60(IIRC) a pour. \n\nAlso no bottle of whiskey tastes exactly the same. They are all blends of different barrels and clear grain alcohol. There is a reason all jack daniels is 80 proof exactly. No two barrels tastes the same. A barrel on a different side of the barn can have a hugely different taste(if you have a super fine palate) than each other. The whiskey master mixes them to create the most uniform taste possible. While fancier high end batches can vary. \n\n"
]
}
|
[] |
[
"https://talesofthecocktail.com/culture/frank-sinatra-jack-daniels?utm_content=bufferb7b43&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer"
] |
[
[],
[],
[]
] |
|
4tp910
|
What's the longest single cell in the world?
|
I'm assuming it's probably going to be a neuron in a blue whale ... but how long is it?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4tp910/whats_the_longest_single_cell_in_the_world/
|
{
"a_id": [
"d5j91lv"
],
"score": [
14
],
"text": [
"Informal estimates place the dorsal root ganglion of the blue whale at ~25 m on average.\n\nIf we include prehistoric animals, though, this figure would not be the largest by a long stretch. The recurrent laryngeal nerve, which does a loop down the length of the neck all the way to the heart (only a fraction of total length, usually), can equal or exceed this figure in length in the longest-necked sauropods."
]
}
|
[] |
[] |
[
[]
] |
|
906tuf
|
why old tech is being shown in new movies
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/906tuf/eli5_why_old_tech_is_being_shown_in_new_movies/
|
{
"a_id": [
"e2o44ss",
"e2o4nde",
"e2oe6tu",
"e2ofxkf",
"e2ohk7z"
],
"score": [
33,
14,
5,
3,
2
],
"text": [
"Because most people can't identify models in simple passing.\n\nIf someone pays for the rights to feature their latest and greatest, the studio would use it, but otherwise it's just a prop phone with the model being completely unimportant. ",
"Not sure about the John Wick case but in case of Spider-man I think it was intentional to point out his humble / poor origins. Similarly, you see old flip phones and other old tech used for its uniqueness or coolness factor.\n\nThis is not the only reason but usually when an old tech is used in high-budget movies/series, it has a specific purpose. In lower budget pieces, it's usual to use whatever the production team could get their hands on / whatever was convenient.\n\nEdit: Another major factor that plays into this is product placement (think futuristic Audi cars in I, Robot) and sponsorship deals.",
"Several reasons.\n\nThey don't think people will notice. For the most part, they're right. Unless it's mentioned by name, most people will just see \"a phone,\" not \"an iPhone 4.\"\n\nThey already have props that look like iphones, so they don't need to make new ones. New props cost money. Old props don't.\n\nEven if they used brand new stuff, by the time they're done filming, it will be old anyway.\n\nIf they feature a brand new product, and that product ends up not selling well, they've tied their movie to a failed brand.\n\nSometimes a company (like Apple) will pay the studio to include their latest product (iPhone X) in a movie. If they put it in the movie anyway, nobody would ever pay for it.",
"I would also venture to say that when they filmed those items might have been new. It isn't like a movie is instantly downloaded to theaters. They edit, reshoot, all that jazz and it may be a year or so from the time shooting completed to the release of the theater. Just a thought.",
"I’ve worked on 40+ feature films as a cameraman. The phones come from the prop department. Unless it’s some special product placement or the director/writer specifies exactly which one to use then they use the same old phones that’s been in their kit for years. I’ve worked on some movies with the same prop team that used the same exact phones across five films. They are usually non working older iPhones or worse.\n\nSometimes the director will request a working phone because he wants something to pop on the screen and they don’t want to CGI it so the crew will scramble to use someone’s personal phone or (more often) we will just use the actors personal phone which often isn’t far away.\n\nThe worst example of old tech is a “found footage” style movie where we see the cameras in the film and prop department busted out some old analog 8mm camcorders for the actors to use despite it being a present day film. Being a cameraman, I pointed out these were ridiculous cameras to use as props for the story but I got just evil glares from the prop crew who didn’t want to deal with it and the director was an idiot that didn’t know the difference.\n\nEven on larger movies such as Spider-Man or John Wick they are still dealing with limited time and budget. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
8b324m
|
bosons, do they facilitate all matter and how?
|
I was under the impression that energy is made matter through Bosons or something at that level. I know this is high level stuff but can anyone simplify it at all?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8b324m/eli5_bosons_do_they_facilitate_all_matter_and_how/
|
{
"a_id": [
"dx3lyeb"
],
"score": [
3
],
"text": [
" > I was under the impression that energy is made matter through Bosons or something at that level.\n\nThis is not really a correct statement. It sounds like you're referring to force carrier particles, which are bosons (a boson is anything with integer spin). There are a number of force carrier particles in the Standard Model of particle physics. They mediate interactions between all of the different particles in the Standard Model. For example, the photon is the force carrier particle for the electromagnetic force."
]
}
|
[] |
[] |
[
[]
] |
|
13wwa7
|
What will happen when we run out of accessible stocks of rare-earth elements?
|
askscience
|
http://www.reddit.com/r/askscience/comments/13wwa7/what_will_happen_when_we_run_out_of_accessible/
|
{
"a_id": [
"c77vqtm"
],
"score": [
4
],
"text": [
"Earth-bound rare earths will be around for a long time. This is why investing in [Planetary Resources](_URL_1_) might not pay off for a while, for example:\n\n[Japan finds major rare earth deposits](_URL_3_)\n\n > JAPAN has found a large deposit of rare earth minerals in its Pacific seabed, enough to supply its hi-tech industries for more than 200 years, a scientist says.\n\nDR Congo has a [crapload of all kinds of minerals](_URL_2_), as does [Greenland](_URL_0_).\n\nAnd yes, there may be substitutes for many rare earth properties:\n\n[Substitutes for Rare Earth Minerals Under Development (MCP, AVL, REE, REMX, GM, TM, PHG)](_URL_4_)\n\n > While rare earths miners like Molycorp Inc. (NYSE: MCP), Avalon Rare Metals Inc. (AMEX: AVL), and Rare Element Resources Ltd. (AMEX: REE) race to begin production, other companies like General Motors Corp. (NYSE: GM), Toyota Motor Corp. (NYSE: TM), and Koninklijke Philips Electronics NV (NYSE: PHG) are working on finding substitutes for the rare metals. Toyota announced last January that the company had developed a new motor for its hybrid cars that does not require lanthanum, neodymium, and dysprosium.\n"
]
}
|
[] |
[] |
[
[
"http://www.guardian.co.uk/environment/2012/jul/31/rare-earth-greenland",
"http://www.planetaryresources.com/",
"http://euromin.w3sites.net/Nouveau_site/gisements/congo/GISCONe.htm",
"http://www.news.com.au/business/breaking-news/japan-finds-major-rare-earth-deposits/story-e6frfkur-1226412676374",
"http://247wallst.com/2012/06/25/substitutes-for-rare-earth-minerals-under-development-mcp-avl-ree-remx-gm-tm-phg/"
]
] |
||
el0liq
|
do nutrients in food change when heated/frozen, and if so, how?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/el0liq/eli5_do_nutrients_in_food_change_when/
|
{
"a_id": [
"fdf49wr"
],
"score": [
6
],
"text": [
"Yes and no. Freezing won't change anything about the nutritional value of food, but cooking will. \n\nThere are many molecules that the human body cannot easily digest, and therefor cannot extract nutrients from. Cooking food can help to break those down into digestible molecules, and allows people to get a greater nutritional benefit from the food. There are also some chemicals our bodies need that can be broken down by high heat, so in those cases cooking can make things less nutritious."
]
}
|
[] |
[] |
[
[]
] |
||
26ed3t
|
why do many companies nowadays see tattoos as being "unprofessional"?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/26ed3t/eli5_why_do_many_companies_nowadays_see_tattoos/
|
{
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"text": [
"Because in much of modern history the people with tattoos have been people very often associated with unsavory organizations, crime, and violence. I think you can understand why companies wishing to present a professional and safe environment would shy away from hiring those with tattoos. That general attitude has been passed down, even though it may not be as applicable nowadays as it was in the past, since many people with tattoos are in no way associated with violence or crime.",
"In general, any body modifications, bar regular ear piercings are seen as \"unprofessional\".",
"\"Nowadays\"?\n\nTattoos have been seen as unprofessional in Western society for ages. They've become vastly more acceptable in the last few decades.",
"It's because of the customers, if the customers didn't care the businesses wouldn't either. I work in a service where I travel from house to house, when I first started I had earnings and tattoos. I went in to the office to quit at the end of my first week, it was rough and the Customers were horrible. My boss told me no, I wasn't quitting. What I was going to do was try the next week without my earnings and longer sleeves to cover my tattoos. Then after that I could do what I want. I'm glad I took his advice, it was a start to the vest job I ever had. Attitudes were drastically different, I was welcome and treated as a friend. \nPeople can be pretty petty, and a business has to make their customers happy. ",
"Tattoos being mainstream(ish) is a recent change. The older generations still see them as something indicative of the low-class/undesirable types. (don't read this wrong, I have a good bit of ink myself.)\n\n",
"It depends on the company. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
||
ci6qt5
|
what purpose do continents serve apart from broad classification?
|
Is there any difference between Asia and Europe or Australia and Africa in terms of administration? How come cultures of Europe and Asia are so different even in neighbouring countries?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ci6qt5/eli5_what_purpose_do_continents_serve_apart_from/
|
{
"a_id": [
"ev1z97y",
"ev1zay0"
],
"score": [
8,
3
],
"text": [
"There is not one but a few different models for the continets. Some of them are just for classification. Some are used to differentiate what is one landmass and what is another. I thing the most common models used are the geopolitical and historic political one. These differentiate between what you could roughly call cultures.",
"Continents are just names we give to large areas.\n\nSome continent divisions have real meaning in terms of geology and wildlife and travel. But we name continents for historical reasons. Europe and Asia are not separate continents in any natural sense, they're just different areas our culture has chosen to name. Some other cultures have different sets of continents, and different numbers of continents."
]
}
|
[] |
[] |
[
[],
[]
] |
|
slk6r
|
Where did energy originate from?
|
This is a question stemming from [this post](_URL_0_) about what propels light. I guess it's another "which came first, the chicken or the egg?" question, but I've always wondered where energy originated from. From my understanding, you need energy to create energy, so where did the first occurrence of energy originate from? There had to be energy to begin with in order for the "Big Bang" to occur, no?
|
askscience
|
http://www.reddit.com/r/askscience/comments/slk6r/where_did_energy_originate_from/
|
{
"a_id": [
"c4ez3nz"
],
"score": [
13
],
"text": [
"[This video is about pretty much exactly what you are asking for, watch it!](_URL_0_) "
]
}
|
[] |
[
"http://www.reddit.com/r/askscience/comments/sktc1/what_propels_light/"
] |
[
[
"http://www.youtube.com/watch?v=7ImvlS8PLIo"
]
] |
|
2yxl7y
|
why are united states parents much more strict with the sexual life of their children compared to european parents?
|
Okay, the title is kind of difficult to understand so let me explain.
My girlfriend is from Germany and she tells me stories of how all of her friends' parents allow their significant others to go away with them on the weekends, go on vacations together alone, etc.
When we asked to do something similar ourselves, my parents were against it and so was her mother (American), however her father (German) seemed very okay with the idea and was almost happy that we asked.
Why are American parents so much less open about these types of things?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2yxl7y/eli5_why_are_united_states_parents_much_more/
|
{
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"score": [
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"text": [
"The main reason is because of the religious background of the United States. ",
"Probably because of religious reasons/status/culture. I don't really know how to explain the phenomenon but what I do know is that for some reason one of the most liberal countries in the world looks is also one of the most strict in this area. \n\nFor example, in public people kiss each other, breastfeed, whatever in South American countries. That sort of stuff is recieved much differently here.\n\nBut If I had to put it to one thing it would be status. Since culture looks down on it, no one wants to look like a skank or the male equivalent.",
"The U.S. in general has a much stronger taboo on sex, especially with regard to adolescents. Remember that we were more or less founded by super-fundamentalist groups who left Europe, and that puritanical base is still very much a part of our culture.",
"because of the fucked-up puritans who were thrown-out of several countries before illegally immigrating here.",
"It's more to do with the same group that advocated prohibition.",
"It's not so bad. \n\nGirls here get off on being \"bad girls\" and I like that. You don't really get that in Europe. In a way, tabboo makes teh secks hot",
"Remember the Pilgrams? Yeah, they were what we call Puritans. Very strict religious sect. We have got more liberal since then, but somethings such as sex have stayed very conservative.\n\nPuritans, Wesleyans, Methodist, Etc, they were (are) all very strict on social life. Most of your mainstream American \"Christians\" have roots in those 3 branches of protestantism.\n\nThat is the historical fact.\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[
"http://truthforsaints.com/denomination_history/denomination_history.html"
]
] |
|
6j0o00
|
how have beauty standards changed so much throughout the years? wouldn't what humans find attractive be genetically ingrained into our heads and not really allow standards to change over time?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6j0o00/eli5_how_have_beauty_standards_changed_so_much/
|
{
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"text": [
"Humans are successful because we adapt to environment. We adapt by learning skills instead of genetically changing. Finding a potential mate is important part of successful survival. If traits we find attractive were genetically imprinted in our brains we wouldn't be able to adapt as fast and well. People would find outdated skills and characteristics attractive and new generation would inherit these characteristics and learn these skills in order to attract mate.\n\nThere are certain universal characteristics that people do find attractive across the species though. Facial and body symmetry (indicates health), scent (indicates genetical compatibility to certain degree), good social behaviour (indicates strong social bonds)",
"A lot of the things we find attractive are not physical attributes but does have different physical manifestations depending on technology and culture. For instance we are attracted to wealth. Previously wealthy people were fat and sat indoor all day as opposed to poor people who were skinny, fit and dark as they worked outside on the fields all day. But as times have changed poor people started working inside and the current symbol of wealth is to have time to exercise and have a nice golden natural skin color.",
"Some standards have changed while others haven't. \n\nThe .7 hip/waist ratio still holds true no matter the size. \n\nI think most of our beauty ideals are designed fir optimal health and ability to procreate. \n\nIn the old days, you had to have enough money to eat and enough fat to get you through a famine. \n\nNow our biggest obstacle to s long life is not famine but heart disease, so we are attracted to slimmer people. \n\nFull lips are a sign of youth, clear skin is a sign of health, and symmetrical features are a sign of genetic hardiness. \n\nIn the past, Anglo Saxons had the most wealth, so those features were the most desired. The Roman nose was revered and the Celtic pug nose was scorned. As Celtic people grew more mainstreamed, those prejudices fell away. \n\nToday, as Hispanic and African Americans achieve increased success and wealth, the physical traits associated with these groups are becoming more desirable. People are dying their hair black, getting Brazilian Butt Lifts, and lip injections. \n\nLips thin with age, so that's another reason that people are attracted to fuller lips - they signify fertility just like the ideal hip waist ratio. ",
"Have they? I find historical portrayals of beauty to be remarkably consistent through time.",
" > Wouldn't what humans find attractive be genetically ingrained into our heads and not really allow standards to change over time?\n\nYes, but the details are left to you and your environment. \n\nYou're programmed to find women attractive (or whatever) once puberty kicks in. Because that's what keeps the species going. To that extent any sexual dimorphism that helps us differentiate the sexes will trend towards \"looking sexy\": tits, hips, beards, shoulders, dicks or lack thereof. Things like \"long hair\" is an example of sexual dimorphism that isn't the result of evolution and your genes in the least. It's entirely social. \"After-market modification\". You've been trained to think that those people with long hair are women. That's not your genes, that's society. \n\nDetails like preferred height, breast size, the ideal shape of the nose, the perfect BMI, skin tone, if you like piercings? All of those are all also social cues you've picked up from your surroundings. Our genes dictate a lot about us, but a lot of it is left entirely up to our environment. And even when our genes steer us towards a certain path, the environment can make adjustments. ",
"One important biological concept missed in discussions here is \"**imprinting**\" - an animal's tendency as an adult to follow its caregiver when the animal was young. [Not just geese](_URL_0_), all animals imprint to varying degrees in differing behaviors.\n\nThat is, we are genetically programmed to be attracted to what we see in a critical learning period during infancy/toddlerhood. If you have tall parents then you will be attracted to tall people, fat parent-figures will cause a child to find fat people attractive.\n\nSo to answer the question.... we are genetically programmed to prefer those who are genetically fit (e.g. clear skin) *but are also genetically programmed to imprint, to like what we see as children (e.g. freckles maybe) so these affinities differ with each person and may change en masse according to culture*. ",
"The evolution of our species occurs via the natural selection of the most beneficial genes. The evolution of culture occurs in much the same way, these have been called memes (not to be confused with internet memes, although it functions in much the same way). These memes would include things like hairstyles, clothing, manners of speaking etc. While there is a base genetic component to sexual selection, there is the memetic component that goes along with it. Our cultural memes can change as quickly as communication between people, which is why beauty standards have changed so quickly within the past century. I like to compare this to firmware and software on a computer, firmware like genes and software like memes. The firmware is more fixed and software can be updated and changed. ",
"They haven't. Being fit has always been attractive. As proof I present [greek statues](_URL_0_).\n\nThat's 3000 years ago. Fit.\n\nNow let's move on 1500 years and we get the [Statue of David](_URL_1_). Fit.\n\nIt very much is genetically ingrained and it has changed less than you'd think. And people saying it's socially engineered *is* the social engineering."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[
"https://www.youtube.com/watch?v=2UIU9XH-mUI"
],
[],
[
"http://etc.ancient.eu/wp-content/uploads/2014/11/1023-1024x768.jpg",
"https://upload.wikimedia.org/wikipedia/commons/thumb/a/a0/%27David%27_by_Michelangelo_Fir_JBU002.jpg/1200px-%27David%27_by_Michelangelo_Fir_JBU002.jpg"
]
] |
||
6dhjkj
|
What happened to the French, Belgian and Dutch colonies when their European owners were conquered by Nazi Germany during WW2?
|
Did their leaders collaborate with the Nazis? Did they stay loyal to their former owners? Where there any attempts of revolutions?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6dhjkj/what_happened_to_the_french_belgian_and_dutch/
|
{
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"di2x16t"
],
"score": [
44
],
"text": [
"I can answer in some detail where the Dutch colonies are concerned. \n\n & nbsp;\n\nThe Dutch had 3 major overseas holdings: the Antilles, Suriname and Indonesia.\n\n & nbsp;\n\nThe Dutch colonies in the West Indies became vulnerable after the Germans occupied the Netherlands in May 1940. The Antilles produced oil and Suriname was a major supplier of bauxite (which was made into the strategically vital aluminium). Especially the United States feared that these vital holdings, in their own backyard no less, would fall prey to the Germans. The Americans cooperated with the British and occupied these territories before the Germans could get to them. This is one good example of how involved the Americans were in World War II before Pearl Harbor. The Dutch government was not too pleased with the US-UK action but pretended to be okay with it. These territories remained peaceful and their resources made a significant contribution to the allied war effort. They were returned to Dutch control after the War ended in 1945.\n\n & nbsp;\n\nIndonesia was an entirely different scenario. The Governor in Jakarta remained in power after May 1940 and still ruled on the orders of the banished Dutch government in London. This would not hold for long however, as in early 1942 the Japanese began their invasion of the Dutch territory. Indonesia was also very rich in natural resources, notably rubber and for that reasons was too great a price for the resources-starved Japanese to let go. Not long after the invasion started did the Japanese occupy the Dutch East Indies. The more nationalist elements in Indonesia were quite happy with this and they were actively encouraged by the Japanese to consolidate their own identity and turn away from their European colonisers. This fit in the broader Japanese strategy to mobilise Asia under Japanese leadership and stop the influence of Western powers there. There was clear collaboration between the Indonesian Nationalists and the Japanese occupation forces. The Japanese occupation was brutal though, partly to the dismay of the Indonesian nationalists. \n\n & nbsp;\n\nThe Dutch loss of control over Indonesia proved crucial. Nationalism had taken a hold on Java, the biggest and most populous island of the archipelago. Despite largely successful campaigns by the Dutch military to regain control over Indonesia, broader geopolitical considerations forced the United States to force the Dutch into giving up their colony (this whole process is worthy of a post in itself). Therefore it could be said that in the long term the Japanese occupation did lead to revolution in Indonesia, as the fires of revolt proved impossible to tame without repercussions after it had been boosted by Japanese intervention. "
]
}
|
[] |
[] |
[
[]
] |
|
22vje1
|
what is passion and where does it come from? (passion for subjects or jobs.) how can it be created?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/22vje1/eli5_what_is_passion_and_where_does_it_come_from/
|
{
"a_id": [
"cgqshiw"
],
"score": [
2
],
"text": [
"This is a good question. Comparable to \"how do you knew when you've met the one?\" You just know. "
]
}
|
[] |
[] |
[
[]
] |
||
170k8t
|
Why don't dead leaves smell bad like other decaying organic matter?
|
Or is the smell just lost in the large volume of air surrounding it?
|
askscience
|
http://www.reddit.com/r/askscience/comments/170k8t/why_dont_dead_leaves_smell_bad_like_other/
|
{
"a_id": [
"c8177r4"
],
"score": [
4
],
"text": [
"It actually takes quite a while for leaves to decay - assuming the leaf was detached from the tree in the fall due to 'normal' circumstances. So, think a regular autumn leaf, not a bunch of leaves that fell off when a branch broke. \n\nDeciduous trees will actually begin pulling nutrients out of their leaves during the autumn. This is evolutionarily advantageous, since the nutrients are not then lost when the years leaves fall off. So what's left when the leaf finally falls off? Just a bunch of tough cell components (lots of carbon) with little nutrients in it. So when the bacteria that decompose organic matter go to town on these leaves, there's not much there. It takes a while for the leaves to be broken down!"
]
}
|
[] |
[] |
[
[]
] |
|
24c9pd
|
are you able to move your hand forward whilest traveling at the speed of light?
|
Say you're in a vehicle that moves at the speed of light and there's no friction, would you be able to move your hand, or anything else forward? Hypothetically ofcourse.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/24c9pd/eli5_are_you_able_to_move_your_hand_forward/
|
{
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"text": [
"every question you have that starts with \"i will be moving at speed of light\" is going to start at impossible. so answering it will be weird.\n\nthings with mass are not going to ever be moving at speed of light, your hand moving at speed of light would have more energy than is in the universe.",
"Well you can't move at the speed of light, so lets say you are traveling at 99.9999999999% of the speed of light. If you moved your hand forward, it would travel faster, but still not at the speed of light, maybe 99.99999999995% of the speed of light.",
"You can't travel at the speed of light. So any question asking \"what would happen if you could travel at the speed of light\" is like asking \"what does physics say would happen in a situation that physics says can't possibly happen\"",
"Setting aside, for the moment, that you can't really travel at the speed of light, let's look at the more interesting question:\n\nIf you're travelling at 99.99999996% the speed of light. And let's say you're in a bus, moving at that speed, where you can walk up and down the aisle.\n\nAt that speed, you're only 0.1 m/s from the full speed of light. You can easily walk faster than that. So what happens if you walk briskly down the aisle of the bus?\n\nWell Special Relativity answers that question. Remember according to SR, there's no such thing as a preferred reference frame. If you're on the bus, the universe is whooshing by at 99.99999996% the speed of light. If you're 'at rest', it's the bus whooshing by. **And both perspectives are equally valid!**\n\nThe first question is \"can you, yourself, in your own perspective, walk briskly down the aisle of the bus?\" And in your reference frame, the bus isn't moving at all. The rest of the universe is moving BACKWARDS at 99.99999996% the speed of light. So sure - That doesn't affect you, so you can walk down the aisle of the bus at 2 m/s and be just fine.\n\nThe second question is, \"can you, according to the guy standing 'still' watching the bus go by, walk down the aisle of the bus?\" And because everything needs to be consistent in special relativity the answer is of course 'yes', but *how* that happens is a bit more complicated.\n\nYour velocity walking down the bus isn't (according to the 'at rest' observer) 2 m/s. You'll be appearing to move much slower than that. In order for all the bits & pieces & causality to work out correctly, that'll mean that the bus is contracted down to 0.00283% of it's original length! So you may be walking down the entire bus, but from the outside observer's perspective, that's not very far.\n\nThe exact numbers are given by this equation:\n\n_URL_0_\n\nMoreoever, from the perspective of the outside observer, **time** is flowing slower for you as well, by the same amount. So over the span of 1 second for an observer, you'd appear to only experience 0.00283% of a second. So you're also moving slower because time is flowing slower for you.\n\nSo it turns out no matter how fast you're going, running down the aisle of that bus, you're not ever going to go faster than the speed of light. You could be running down the aisle at **half** the speed of light, and your speed according to the \"at rest\" observer would only go from 99.99999996% to 99.99999998%. No matter how fast you go on the bus, all you can do is add 9's to the end of the number, but you'll never get *to* 100%, nor higher, for that matter."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://upload.wikimedia.org/math/4/1/8/41898d25611a3359aa6bb3a9a7cac36a.png"
]
] |
|
tpfvx
|
Since the Earth is getting more mass in the neighborhood of 100 tons a day, will the gravitational pull be strong enough to pull the moon into it?
|
Saw this post today: _URL_0_
Title asks it all.
Thank you.
|
askscience
|
http://www.reddit.com/r/askscience/comments/tpfvx/since_the_earth_is_getting_more_mass_in_the/
|
{
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"c4ole15",
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],
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2
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"text": [
"100 tons compared to the mass of the earth (~6x10^24 kg) is barely a rounding error.\n\nIt would take approximately 1.8 x 10^14 years to increase the mass of the earth by 1/1000 of it's current mass at that accumulation rate. The universe is only about 13.75 x 10^9 years old. So the Earth's mass isn't changing much percentage wise.\n\nAlso, the moon is moving away due to tidal interaction with the earth transferring energy to it.",
"Unfortunately whoever posted that to TIL misunderstood the article. Although the Earth is gaining 100 tons of meteorite mass per day it is also losing mass via the escape of gases.\n\nWhether or not Dr. Chris Smith and David Ansell are correct about the Earth losing 50,000 tonnes in mass per year or not, clearly in no way was NASA implying that the Earth's gain of 100 tons of mass in meteors is actually an overall net gain."
]
}
|
[] |
[
"http://www.reddit.com/r/todayilearned/comments/toekr/til_the_earth_gets_a_100_tons_heavier_every_day/"
] |
[
[],
[]
] |
|
1ex7no
|
how vinyl record players can play not only the pitch but also other details of some sound
|
How can vinyls store different sounds at the same note, because they have the same frequency and so the grooves would be the same?
Eg. Middle C on a piano vs same note on guitar.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ex7no/eli5_how_vinyl_record_players_can_play_not_only/
|
{
"a_id": [
"ca4ni6z"
],
"score": [
4
],
"text": [
"Different instruments produce different shapes of sound wave. [Here](_URL_0_) are a few examples.\n\nThese are stored on vinyl by physically making the edge of the groove into the shape of the sound wave that the instrument makes."
]
}
|
[] |
[] |
[
[
"http://amath.colorado.edu/pub/matlab/music/F_InstrumentWaves.gif"
]
] |
|
ylowe
|
how and by whom are generation groups (x,y,z etc.) determined?
|
I understand the concept of generations in a family (daughter, mother, grandmother), but I don't understand the line that separates generations in a culture. As new people are born everyday, and there are people of every age at any given time in a country, how/who decides which generation they are placed in?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/ylowe/eli5_how_and_by_whom_are_generation_groups_xyz/
|
{
"a_id": [
"c5wv0ym"
],
"score": [
3
],
"text": [
"Marketers, mainly. Most of the time, you get a steady drip-drip-drip of people being born every year; there's about as many 7 year olds as 5 year olds or 9 year olds or whatever. \n\nBut the World Wars, particularly WWII, fucked that up: All over the world, the young people who would normally be getting married and having their first kids weren't, because the young guys were in the army and times were tough, so even people who were married put off having kids if they could. Then the war ends and all of a sudden you had like 6 years worth of kids being born at once. That changes things up: You have to build bigger schools, bigger toy stores, more cribs and braces and so forth all at once. That forced the people who sell stuff to pay particular attention to what was going on with young people, because they knew that in, say, a couple year's time there was going to be 6x the normal demand for bicycles or prom dresses or whatever. So they started doing more advertising aimed at young people, more TV shows and movies and books specifically aimed at young people and so on, all through the years. Young people are pretty much always rebellious in their late teens early 20s; but when you have six times the normal number of them at once all that rebellious energy can cause much more profound changes in society than it normally does. Viola: The 60s.\n\nSo it wasn't until the baby boom came around that people really started paying attention to the idea of generations as an important thing. \n\nBy the time the boomer wave was passing into adulthood marketers were used to this idea that people the same age as each other have the same types of ideas and desires, and that those desires are different from those of their parents and so they know they'll have to adapt themselves. (Technological change helps too.) They're the ones whose bottom lines are affected, and they're the ones who pay attention to all this stuff and write most of the BS you see about how generation whatever thinks about the world. "
]
}
|
[] |
[] |
[
[]
] |
|
n0wts
|
What originally defined the human size/mass? Why are most of us 1.5-1.9m tall instead of 0.5m or 20m tall?
|
What would be the minimum possible mass for a human to survive? I'm assuming a baby is the smallest size. Would it be possible to scale down any smaller, ie in atoms or is that the smallest we could possibly be? Why don't we stay at baby size, why do we grow to 1.5-1.9m in average and then just stop? Why doesn't our body just keep scaling up to like 20m+? I'm assuming there's a marker in our DNA that keeps us from growing to gigantic proportions. But how did it get there? What defined that original mass/height in the first human? If you scaled everything up in the human body, all the organs, more skin etc, is there a theoretical maximum size we could be? I know we're supposed to have evolved from apes so maybe we get the general sizing from them, but then what defined the ape's mass? You could keep going back further, what defines trees are going to x height and width, cows smaller, birds even smaller, insects even smaller and so on?
|
askscience
|
http://www.reddit.com/r/askscience/comments/n0wts/what_originally_defined_the_human_sizemass_why/
|
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"Evolution is an optimising process, it's always making tradeoffs between competing criteria to find the highest fitness for the environment. There are advantages to being bigger, as well as disadvantages. On the simplest level, if you're bigger you can win more fights, but you need more food. So maybe you want to be as big as you can be for the amount of food available. But htere are more factors than just those two of course. The size an organism ends up approximating the optimal tradeoff between all of those sorts of factors for the environment that organism lives in. Interestingly over the last few thousand years people have become a little bigger, and one of the proposed reasons for this is that we have become better at growing food, so the problem of being too big and needing too much food is less of an issue than it used to be. Also of course even genetically identical people will end up different sizes if you feed one much more.\n\nRegarding being massive, the issue is the [square-cube law](_URL_0_). Basically weight is determined by volume, so it's size cubed, but muscle strength is determined by muscle cross section, which is area so it's size squared. As you get bigger the amount of strength you have goes up by squares, but the amount of weight you have to lift goes up by cubes. So there's a limit to how big you can be and still lift your own weight. This is also a big part of why ants can lift so much relative to their weight.",
"Evolution is an optimising process, it's always making tradeoffs between competing criteria to find the highest fitness for the environment. There are advantages to being bigger, as well as disadvantages. On the simplest level, if you're bigger you can win more fights, but you need more food. So maybe you want to be as big as you can be for the amount of food available. But htere are more factors than just those two of course. The size an organism ends up approximating the optimal tradeoff between all of those sorts of factors for the environment that organism lives in. Interestingly over the last few thousand years people have become a little bigger, and one of the proposed reasons for this is that we have become better at growing food, so the problem of being too big and needing too much food is less of an issue than it used to be. Also of course even genetically identical people will end up different sizes if you feed one much more.\n\nRegarding being massive, the issue is the [square-cube law](_URL_0_). Basically weight is determined by volume, so it's size cubed, but muscle strength is determined by muscle cross section, which is area so it's size squared. As you get bigger the amount of strength you have goes up by squares, but the amount of weight you have to lift goes up by cubes. So there's a limit to how big you can be and still lift your own weight. This is also a big part of why ants can lift so much relative to their weight."
]
}
|
[] |
[] |
[
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"http://en.wikipedia.org/wiki/Square_cube_law"
],
[
"http://en.wikipedia.org/wiki/Square_cube_law"
]
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|
jmzpr
|
what is "fair trade" and why should i care that my coffee is labelled as such?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/jmzpr/eli5_what_is_fair_trade_and_why_should_i_care/
|
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"Originally, fair trade was about a group of people that came together and said that they would pay the farmers that grew coffee a \"fair\" price. They wanted to do this in order to help them make more money, so that we weren't just using (exploiting) them. A lot of coffee comes from the poorest parts of the world, even though it gets used by the richest parts of the world, so the system was designed to help these farmers. The system pays these farmers slightly higher than what the world agrees on, thus being \"fair\".\n\nNow the problem with Fair Trade. There's delicious coffee, and then there's the crappy coffee you find at Wal Mart. Let's say you're a farmer, and you have two separate batches of coffee to sell. One is delicious, that you could probably sell for more money, and one that's kind of crappy, that would sell for less money. Wouldn't you sell the crappy coffee to the Fair Trade people, in order to make more money than you could have, selling to anyone else? The delicious coffee gets sold at an even higher price than that, so you're still making money. This means \"Fair Trade\" coffee CAN be less delicious than if you were to buy coffee from the indie cafe down the street, that really cares about quality. \n\nFair Trade also claims to be a non profit, and takes some money from the people that buy their coffee instead. This money pretty much goes to telling everyone what a nice bunch of people they are (advertising/marketing), instead of going back to help the farmers. Then, the people that buy the coffee from the Fair Trade people, let's say Starbucks, can ALSO say that they're trying to do good. They have good intentions, but they're not really helping us have good coffee WHILE helping the farmers too. \n\nThis is where Direct Trade comes in. Before, the Fair Trade people were the only people that could actually PROVE that they were helping farmers. Direct trade means that a bunch of guys are going to the farmers, and telling them how to grow coffee in the best way possible. They give these farmers \"coffee tests\" to make sure that the coffee will turn out to be absolutely delicious, and if the farmers pass these tests, they get rewarded by being paid more. \n\n==\n\n**Edit** - I'm sorry if this isn't too easily understood by a five year old :/ I tried my best! Feel free to ask me to clarify on anything, though. More reading for non 5 year olds [here](_URL_0_) about the problem with fair trade.",
"Originally, fair trade was about a group of people that came together and said that they would pay the farmers that grew coffee a \"fair\" price. They wanted to do this in order to help them make more money, so that we weren't just using (exploiting) them. A lot of coffee comes from the poorest parts of the world, even though it gets used by the richest parts of the world, so the system was designed to help these farmers. The system pays these farmers slightly higher than what the world agrees on, thus being \"fair\".\n\nNow the problem with Fair Trade. There's delicious coffee, and then there's the crappy coffee you find at Wal Mart. Let's say you're a farmer, and you have two separate batches of coffee to sell. One is delicious, that you could probably sell for more money, and one that's kind of crappy, that would sell for less money. Wouldn't you sell the crappy coffee to the Fair Trade people, in order to make more money than you could have, selling to anyone else? The delicious coffee gets sold at an even higher price than that, so you're still making money. This means \"Fair Trade\" coffee CAN be less delicious than if you were to buy coffee from the indie cafe down the street, that really cares about quality. \n\nFair Trade also claims to be a non profit, and takes some money from the people that buy their coffee instead. This money pretty much goes to telling everyone what a nice bunch of people they are (advertising/marketing), instead of going back to help the farmers. Then, the people that buy the coffee from the Fair Trade people, let's say Starbucks, can ALSO say that they're trying to do good. They have good intentions, but they're not really helping us have good coffee WHILE helping the farmers too. \n\nThis is where Direct Trade comes in. Before, the Fair Trade people were the only people that could actually PROVE that they were helping farmers. Direct trade means that a bunch of guys are going to the farmers, and telling them how to grow coffee in the best way possible. They give these farmers \"coffee tests\" to make sure that the coffee will turn out to be absolutely delicious, and if the farmers pass these tests, they get rewarded by being paid more. \n\n==\n\n**Edit** - I'm sorry if this isn't too easily understood by a five year old :/ I tried my best! Feel free to ask me to clarify on anything, though. More reading for non 5 year olds [here](_URL_0_) about the problem with fair trade."
]
}
|
[] |
[] |
[
[
"http://www.ssireview.org/articles/entry/the_problem_with_fair_trade_coffee/"
],
[
"http://www.ssireview.org/articles/entry/the_problem_with_fair_trade_coffee/"
]
] |
||
cnsa6a
|
how do cpu temperatures drop so rapidly?
|
I was using Intel Power Gadget to monitor my Mac’s CPU temps, and I noticed that the temperature would sometimes drop from 80 degrees to around 70 within a second. It makes sense to me why the temps would increase cause the electrons moving through the CPU cause that. But how can the temps drop so immediately when all these processes are going on?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cnsa6a/eli5_how_do_cpu_temperatures_drop_so_rapidly/
|
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"Depends on the exact configuation, but computers have fantastically efficient cooling systems onboard to keep the CPU at safe temperatures when just idling/keeping the OS running, that can max out to disperse more heat when it's doing heavy processing.",
"It's measuring the temperature of the CPU die, which is very small (The size of your thumbnail, or a US dime). The die has a very low thermal capacitance, meaning it does not store heat very well. So when it stops producing as much heat, the temperature drops very quickly as the head spreader and heat sink absorb and dissipate the heat.",
"The temperature sensor you're reading is most likely part of the silicon die, and inside a particular CPU core(which is very small, so it doesn't have much thermal mass). As the silicon in a CPU has the same atomic structure as diamond, it has a very high thermal conductivity, so when heat stops being generated in this particular core, the core temperature drops to the average die temperature very quickly. \n\nIt takes much longer for the average die temperature or the heatsink temperature to change. This is why when you start a stress test the temperature will jump up almost instantly, but then slowly creep up as the heatsink comes up to the new equilibrium temperature. \n\nFor an analogy: The CPU core(what you're measuring), is the heating element of a stove, while the heatsink temperature is the pot of water on top of it. If you boil a pot of water, the heating element will heat up much more quickly than the pot of water, and can get hot enough to glow red. When you turn the burner off, it very quickly cools down to not-glowing temperatures, but it will take a long time for the temperature to go all the way back down to room temperature because the pot of water is still holding a lot of heat."
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[],
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|
23sgc6
|
Is rain water pure H2O, or does it pick up other elements from the air on the way down? If not, why?
|
askscience
|
http://www.reddit.com/r/askscience/comments/23sgc6/is_rain_water_pure_h2o_or_does_it_pick_up_other/
|
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"No, rain water is not pure. For starters, it has to have a \"cloud condensation neuclei,\" basically a particle on which water forms. When the cloud becomes dense enough, rain begins to fall. The rain will react with various gasses and particulates on the way down, including hydrogen sulfide and carbon dioxide, creating sulfuric acid and carbonic acid respectively. In addition, rain water may pick up particulates such as pollen and carry them down. So when it reaches the ground, although it is primarily water, it is far from pure."
]
}
|
[] |
[] |
[
[]
] |
||
2pw4pu
|
paradox?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2pw4pu/eli5_paradox/
|
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"Don't post just to complain.\n\nAlso, you're using \"paradox\" incorrectly.",
"Sometimes people don't always know how to phrase their answers right, sometimes people ask questions that necessarily demand a degree of technicality. It's nice for people to be volunteering their time to answer nonetheless, where serious. \n\nAnyway this is Reddit. If you believe you have a better way of explaining something that better suits the ELI5 theme, you're welcome to. "
]
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[],
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4ai49v
|
why are so many americans hooked on opiate pain pills?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4ai49v/eli5_why_are_so_many_americans_hooked_on_opiate/
|
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"We are a pharma loving people. There is a newer prescription pill epidemic and I think it partially reflects that. People tend to think that because someone gets a prescription for these pills that they are safe and sanctioned. And in ways it is better than heroin in that it is regulated. However, many people are going from the pill habit onward. I guess one could say that it is a gateway in that case. We also have really bad laws regarding less addictive substances. There are many ways to get them. Some people could be legitimately taking them but one of the hallmarks of addiction is gaining tolerance. Fraud and all kinds of strange deals are expected when someone is on these. It's surprising that the visitees were high functioning but IME they will either let the addiction go or let it take hold eventually.",
"First of all, most synthetic opiates are extremely addictive. For reasons I cannot explain, doctors in the USA still tend to prescribe these rather than the less addictive kinds of opiates (tramadol for instance). In Europe, prescriptions for these kinds of opiates are very tightly controlled - not many european doctors prescribe oxycodone or morphine outside of a hospital setting, so these pills seldom leave that setting. Hence, addiction is relatively rare due to oversight from hospital personnel.\n\nThen, there's the fact that US pharmacies aren't interconnected most European pharmacies are. I don't know about the UK, but in the NL all pharmacies are connected to a central database where prescriptions are checked. Anyone shopping for pharmacies would be caught quite easily.\n\nFurthermore, most European doctors use digital systems to communicate with pharmacies. This makes faking a prescription next to impossible. In the US, they still use paper prescriptions quite often, which allows for forgeries, theft and illegal transfer. \n\nIn the end, it all has to do with the relative ease one can get ones hands onto a substance. Pill-popping is most popular in rural parts of the USA, where illegal drugs are otherwise hard to come by. In Europe, it is more easy to obtain heroin than oxy or other such drugs. Hence, relatively speaking, more people are addicted to prescription pain meds in rural US, and more people are addicted to heroin in Europe.",
"I think that the problem is getting a little better. I went in for stitches recently and they gave me one hydrocodone. I think the problem is that for a long time Doctors over prescribed pain killers in America. It was really a matter of convenience. Patients didn't want to get 20 pills, but need 32 pills. Forcing them to go back to the doctor. So instead Doctors prescribed a 20 pill bottle with one refill if necessary. \n\nEveryone always got the refill, and then left the pills in the cabinet. Those pills got stolen or the person began taking them not for pain. So people slowly got addicted to pain killers which are in the Opioid family, and are very addictive. I think that a lot of Americans have a hard time seeing something prescribed to them from a doctor as being dangerous, but pain killers are. \n\nThis is also coupled with the fact that Americans get very little vacation. So, a lot of people are stressed and take little pills to make themselves feel better about there stressful lives. \n\nI worked in Hospitals for a while, and I do believe the problem of over prescribing is getting better here. Doctors realize the dangers of Opioids a great deal more today than they used to.",
"This is also a problem in Canada. My mother worked at a methadone clinic and 80% of her patients were prescribed painkillers when it was not necessary and became addicted as a result. We love medicating everything, covering up symptoms so people can continue to work. I was prescribed percocets for my wisdom teeth. Definitely did not need them nor did I ask. I moved to NL and here they dish out paracetamol or ibuprofen and that is it unless it's very severe. I noticed there's more of a focus on physiotherapy etc here for pain rather than just giving out meds.",
"In the last year, I went to the dentist and twice he handed me an opiod prescription without me asking. He did not mention trying an NSAID first, which is very effective for tooth pain. He was just building a new business and ethics be damned. ",
"when I had my wisdom teeth pulled a few years ago I was prescribed Oxycodone for the pain. I sort of get how people can get addicted to it, the stuff is amazing for pain relief. I found it a bit strange how the doctor didn't seem to have any worry about giving a College-aged kid highly addictive drugs.",
"Let me tell you the story of the local Dr. Feelgood pill pusher from my tiny town. On a quiet street nestled between a garage, a day care and a t-shirt shop, there is an abandoned doctors office. A few years ago, in a town of 2500 people, it would not be uncommon to see over 100 people milling about in the parking lot waiting there turn to see the \"doctor\". Office was open 2 days a week. There were so many people there that he put picnic tables and pop machines outside of his little 900sq ft house turned office and paved almost an acre for parking. Hundreds of people a day. Cars with license plates from one hundred miles or more away ( in Indiana you can tell where a car is from based on a county code on the license plate.) When they finally caught him, I think his average time per patient was about 90 seconds or less. He only took cash. He didn't file with insurance. He had an ATM in the office. His prescriptions were always the same Oxy or Hydrocodone and Xanax. Tens of thousands of scripts for the same shit. Same people. Killed a couple. State finally shut him down. \n _URL_0_\n\nGreat, right? No. While I didn't exactly like the guy by any means, he was, in a sort of way, maintaining the addicts. Most of his customers looked to be construction workers or factory workers. Guys that got hurt on the job and just ended up either still in pain or addicted. What happened after they could not get their prescribed, legal fix? Heroin. We now how a heroin problem that we never saw before. Needle exchanges and HIV outbreaks. They made an effort to stop the dealer with out ever considering what would happen to the addicts. Oh well.",
"Most people answered this well enough already but I wanted to chime in that drugs reps for Purdue hit the doctor's offices *hard* when Oxycontin came out. They touted it as the next best thing to god. It would cure any pain, it's got a mechanism of action that didn't allow for abuse! (when in reality, simply crushing it got rid of the time release). They gave out so many free samples **and told the doctors to give it a try on patients with *any* pain**.\n\nOur doctors were listening to drug reps about what to prescribe patients. Big pharma is awful and it's done it's part in making the healthcare system in the US awful too.",
"You're not an addict if you are in real pain. When u start taking them knowing you have no pain, that's when trouble starts.",
"The bottom line is that in Europe health care is a service, but in the US health care is a business. If you can make loads of money selling addictive prescription painkillers to people who don't need them, someone is going to take advantage of that system unless there are regulations preventing it.",
"You've had a couple good answers, and that's great.\n\n[NPR However, has had a number of articles on this recently](_URL_2_). I'm sure any on that list will shed some light on the topic for you, but [this one](_URL_0_) and [this one in particular](_URL_1_) I remember and think might help address the question specifically.\n\n\nThe \"Listen to this Story\" buttons are way up top if you prefer audio over reading.",
"Finally something I have expertise on! Pain is a complicated mechanism that is still not well understood. Opioids enter the body through endogenous mu opioid receptors and are some of the most effective drugs there are in treating pain, at least initially. There is a signaling process involved, either with the g-protein receptors or the beta-arrestin signaling, or maybe the GRK dephosphorylation process, that causes opioid tolerance. This means that the same amount of drug will stop relieving pain, yet still cause the same side-effects. People in chronic pain will need their prescriptions gradually increased, while side-effects also increase (which is a factor in the huge number of opioid-related deaths in the US). This tolerance can occur after 2 days of taking morphine and the level of opioid required for tolerance to develop is less than the dose required for blocking pain.\n\nThat's the mechanical aspect, but like I said pain is not well understood. There is an emotional aspect as well where patients take the pain stimulus and see it as an emotional negative. When patients are stressed this emotional aspect is increased and patients returning to a high stress environment after receiving surgery or injury are at a greatly increased risk of developing chronic pain. There have been many studies on the effect of stress on pain. You may have noticed that when you are sick or stressed your skin feels \"tender\" this is allodynia, which is basically just your nerves reacting to non-painful stimuli as though it is painful. People with chronic pain can get severe allodynia which can spread to large portions of their bodies, making it extremely painful to do daily tasks- some can't put on socks or shirts because the material feels like it's burning their skin. When you are stressed and become injured it does something to prime your sensory system where you are more prone to developing chronic pain.\n\nSo in the USA where people are lucky to get a few weeks off a year, and low-paying jobs don't even offer sick leave, stress gets piled onto patients as soon as they are awake from surgery. This increases the chance the develop chronic pain, which then needs to be treated. Unfortunately opioids are the best treatment for pain and doctors didn't realize how bad the side-effects could get or the addiction that would occur as tolerance to opioids grew. There are some alternatives now and doctors are trying to avoid prescribing opioids unless everything else fails to provide relief, but the alternatives are not as good. Sometimes patients have to accept being in pain for the rest of their lives, which can be very depressing AND being depressed increases allodynia and risk of chronic pain, so it's like a double-whammy of pain for the patients.\n\nIt should also be mentioned that it may be a cultural thing. Researchers have measured pain scales in different parts of the world and seen that how patients react to pain culturally seems to have a large impact on the percentage that develop chronic pain. For example they interviewed Chinese rice workers who were unable to stand straight and had all the signs of extreme back pain. Yet the patients never complained about it and when the researchers asked if they were in pain and wanted medication for it they said they weren't in pain it was just how their bodies were now, and seem to think it was funny the researchers didn't expect old workers to be stiff. Someone in America with the same symptoms would most-likely try to get opioids so they could go back to feeling 100% again. Also in other countries pain is accepted as a thing that happens and is accepted. In America pain and weakness- such as being old- is unacceptable and quick fix pills are needed to help keep pace with the long workdays and weeks.\n\ndisclaimer: the mechanistic stuff is accurate, the cultural views are my own. :-)"
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[],
[],
[],
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"http://www.npr.org/sections/health-shots/2016/01/11/462390288/anatomy-of-addiction-how-heroin-and-opioids-hijack-the-brain",
"http://www.npr.org/2015/12/30/461519814/doctors-look-to-prevent-abuse-in-midst-of-opioid-epidemic",
"https://www.google.com/search?q=npr+opiate+addition&ie=utf-8&oe=utf-8"
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||
25mkqs
|
What made the United Nations significantly different from the League of Nations?
|
I know America was in the UN but not the LoN, but I asking about more structural things, in terms of their charters, their powers and their organization.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/25mkqs/what_made_the_united_nations_significantly/
|
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"One of the larger differences is that the League of Nations had no teeth, it had no military force of its own to physically put down an aggressor. The League of Nations provided that if an aggressor would not stop it could use military force but it having no force if it's own made it an empty threat. \nA nation would have to volunteer it's military but that means that nation would be declaring war.\n\nMembers of the UN volunteer troops to UN command, that allows the UN to have teeth when needed( like in the Korean War)\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.historylearningsite.co.uk/leagueofnations.htm"
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|
110o3n
|
humanism
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/110o3n/eli5_humanism/
|
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"See /r/humanism\n\n > Humanism is a democratic and ethical life stance, which affirms that human beings have the right and responsibility to give meaning and shape to their own lives. It stands for the building of a more humane society through an ethic based on human and other natural values in the spirit of reason and free inquiry through human capabilities. It is not theistic, and it does not accept supernatural views of reality\n\n > -- International Humanist and Ethical Union, minimum statement on Humanism.\n\nor\n\n > I am a humanist, which means, in part, that I have tried to behave decently without expectations of rewards or punishments after I am dead.\n\n > -- Kurt Vonnegut"
]
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|
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[] |
[
[]
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2mt3su
|
Is it possible to melt snow (or whatever) with sound?
|
I was reading another post about how the speed of sound changes depending on density and stiffness and other properties and one commenter was talking about how snow is an excellent sound absorber/dissipator/what have you. Because the sound is converted into thermal energy when it is absorbed/dissipated, how loud would it need to be for a noticeable amount of snow to be melted. (Of course this is totally ridiculous, but can anyone chime in?)
|
askscience
|
http://www.reddit.com/r/askscience/comments/2mt3su/is_it_possible_to_melt_snow_or_whatever_with_sound/
|
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"text": [
"I was the guy who made that comment on the other post. While technically you could input enough energy to melt snow, the amount of energy contained in sound is very small.\n\nAssuming you have 1 g of snow at 0 C, the amount of energy needed to melt that is 334 Joules. The sound from an entire orchestra only amounts to 1 W of energy. If you could somehow focus all of the energy from the symphonies music onto that ice, it would take 334 seconds to melt it, a full 5 minutes. And that's an entire symphony focused directly on a little more than a tablespoon of freshly fallen snow\n\nHope that answers your question."
]
}
|
[] |
[] |
[
[]
] |
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tf7wi
|
Why do plants go "limp" after you pick them?
|
There's a fern growing on my lawn, and I plucked a small part of it off, to bring inside and look at under a microscope.
Within 15 minutes of picking it off of the main part of the plant, it was very limp, whereas it was somewhat stiff beforehand.
I understand it's because it's not attached to the stem of the plant, but *why* does it go limp?
|
askscience
|
http://www.reddit.com/r/askscience/comments/tf7wi/why_do_plants_go_limp_after_you_pick_them/
|
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"text": [
"Plants use turgor pressure to maintain the rigidity of structures. When you pick the plants they lose pressure because they lose water. When they lose turgor pressure, they wilt."
]
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|
[] |
[] |
[
[]
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4r2bxd
|
how is monster energy allowed to claim some of their drinks contain zero calories, yet there's 4g of carbs per can?
|
And carbs contain calories. Also, they claim zero sugar, yet there's 2g per can of Erythritol, which is a sugar additive?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4r2bxd/eli5_how_is_monster_energy_allowed_to_claim_some/
|
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"text": [
"The FDA allows numbers on Nutrition Labels to be rounded to the nearest whole number. If those 4g of carbs amount to less than half a calorie per serving, then the manufacturer is going to take advantage of the situation and put 0. \n & nbsp; \nAs for the erythritol, the regulatory definition of what counts for the purposes of ingredients and nutritional labeling doesn't always line up with scientific definitions of the same. The law that talks about what products can make a \"zero sugar\" claim uses the wording \"The food contains no ingredient that is a sugar or that is generally understood by consumers to contain sugars,\" and I imagine the manufacturer would claim that consumers don't generally understand sugar alcohols to be sugars. \n & nbsp; \nAnd for all this seems like the Labeling requirements are filled with loopholes, the FDA does try to press back against some of the more flagrant attempts by the industry to game the system. A few years back they issued a \"stop doing that\" notice to some manufacturers who were trying to disguise sugar on their ingredients labels by calling it \"Evaporated Cane Juice\". "
]
}
|
[] |
[] |
[
[]
] |
|
g1zy4
|
With the recent horrifying earthquake that hit Japan, I'm curious: With today's technology and know-how, how difficult is it to predict an earthquake?
|
askscience
|
http://www.reddit.com/r/askscience/comments/g1zy4/with_the_recent_horrifying_earthquake_that_hit/
|
{
"a_id": [
"c1kbnym",
"c1kbra0",
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"c1kcop8",
"c1kdpds"
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"score": [
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11,
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2
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"text": [
"Prediction of catastrophic failures is basically impossible. Scientists have been making progress in being able to measure tectonic pressures in earthquake hotspots, but it is still just an indicator and not a full blown predictive theory. ",
"Basically impossible. There's a guy in Italy (Giampaolo Giuliani) who claims he can, but nobody believes him.",
"Part of my PhD work focused on understanding how stress is released and transferred during earthquakes. We are still very far away from being able to predict earthquakes. Right now predictions are all based on recurrence intervals and statistical calculations. We can say how likely it is for an earthquake to occur in a given region and make some estimates (based on stress build up) for the size of the earthquake, but not when or exactly how large. Think of it is knowing that you live in a 100 yr flood plain, or 500 yr flood plane.\n\nWhat is really fascinating about today's magnitude 8.9 event in Japan is that there was a magnitude 7.2 foreshock only 40 km away. Foreshocks are rather rare, so I think there will be some intriguing scientific discussions that follow.",
"All the blah blah aside. The reality is that we can't.\n\nBasically what the geo/planetary etc. scientists can do is give us probabilities within a time window. The type of stuff useful for insurance companies' risk analysis.\n\n",
"Actually, [according to this story](_URL_0_) the Japanese early warning system sent out a warning to millions of people about 1 minute before the quake actually struck. It is astonishing to me that this actually worked, I was always under the impression that any system of this sort was basically impossible. A minute may not seem like much, but I am sure it gave many people the warning they needed to get to safety."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[
"http://www.montrealgazette.com/news/Alert+sounded+minute+before+tremor+struck/4425621/story.html"
]
] |
||
54fzqx
|
why does cannabis make people sleepy after the high wears off?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/54fzqx/eli5_why_does_cannabis_make_people_sleepy_after/
|
{
"a_id": [
"d81lm6s",
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"d81szpi",
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"d81ta0k",
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],
"score": [
616,
49,
179,
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2,
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2,
2,
11,
2,
2
],
"text": [
"CBN is a degradation product of THC and other cannabinoids. It is highly sedative.\n\nThere is also the issue of flooding the endocannabinoid system (which regulates our hormonal functioning and a number of other systems) with exogenous cannabinoids producing a temporary down-regulation. \n\nIf you don't want to get tired from smoking pot you can do two things: Smoke less and choose sativa dominant strains. Smoking less is the key really. In moderation cannabis will not produce the burnt out effect that heavy smokers are familiar with. ",
"Not every strain of cannabis will make a you sleepy. This is one of the widespread misunderstandings that prohibition has caused. As a professional in the medical cannabis community in California, we see many patients who come specifically for Sativa heavy strains that energize, and increase activity levels even after the effect wear off. Dispensary grade cannabis does not have to make a person couch-locked, lazy brained or sleepy. Over the years so many people have experienced dirty weed that is old, laden with pesticides or Indica heavy causing them to believe that is what cannabis is about. Nothing could be further from the truth. This being said, every person's endocannabinoid system will process CBD's differently. If you are game, you can experiment with different strains and find what works best for you.",
"Im a heavy pot smoker and the groggy, burnt out feeling goes away after a long...long time. When i smoke im 3 things, happy, hungry, and happy because im high and forgot what else i was going to say.",
"I've never noticed a difference between indica/sativa strains. Having tried 100% sativa, 100% indica, and hybrid(50/50.) IMO the biggest factor that causes sleepiness is the method of use. Vaping and edibles don't seem to create as much fatigue compared to smoking. This is due to the lack of carbon monoxide, other combustibles when you smoke. There's also evidence that marijuana increases melatonin significantly.",
"Also, the point of harvest makes a significant difference on the \"sleepiness\" of the high.\n\nLate harvest with trichromes turning brown will make you much more sleepy, so it's both strain and harvest timing that combine to make you sleepy.",
"you should really ask this in /r/askscience because here you'll probably just find a lot of anecdotal explanations.",
"Depends on the strain and your physiology, not everyone gets sleepy and not everyone gets hungry. Sometimes you'll get 'sleepy' tired but it was just because you were already tired and smoking helped you 'chill out' other times you will be stressed and then get the 'happy' 'high creative' go and not get sleepy at all. I recommend you to try Maui or Haze, tbqh any Sativa strain. ",
"I've never had anyone be able to explain why it never makes me tired (opposite - takes me ages to fall asleep after smoking or ingesting) or hungry (I have to force myself to eat). Fwiw, I'm a long time user and don't have problems sleeping or with hunger any other time. ",
"After? It's always made me super sleepy *during* the high. The moment it starts to take effect, it takes a *TON* of effort for me to not just curl up and go to sleep.",
"I would often smoke pot before bed to help with insomnia. I've since abstained from weed for a 3 month trial. There's a product you can get on Amazon called \"True Calm\" and it almost makes me sleepy like pot did. Does anyone know why?",
"In relation to your body, cannabis is a stimulant. Measure your heart rate before and after partaking and you will find a approx 10-20 bpm increase when under the influence. When this wears off, you will feel relatively lower in energy due to less blood being pumped.\n\nIt is also a stimulant in relation to your brain and its reward center so everything seems more fun when you're high. When this effect disappears then everything seems more boring. Being bored means you're more likely to go to sleep.\n\nAlso, add in the chance of a sugar crash/food coma from all the snacks you just ate."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
zi72o
|
Are most living organisms today considered to be more complex than those, say, 70 million years ago?
|
askscience
|
http://www.reddit.com/r/askscience/comments/zi72o/are_most_living_organisms_today_considered_to_be/
|
{
"a_id": [
"c64t856"
],
"score": [
4
],
"text": [
"No. First off complexity is a very hard thing to measure. Are ants more complex than non-hive insects? But most importantly most life on Earth (by any measure, number, mass, etc.) is single celled. So most life on Earth is just as complex as it was.\n\nNow there may be a slight increase on some \"average complexity\" (assuming that term has meaning). There is some minimum complexity to to a living organism but no obvious maximum. Likely this is a bounded random walk and so there will be over time a slight movement from the wall. \n\n"
]
}
|
[] |
[] |
[
[]
] |
||
alvd2w
|
AskHistorians uses a 20-year rule to consider something to be "history." Is this a common rule among historians, or is it just a pragmatic measure to moderate this community? If so, how do scholars decide when something can be called "history"?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/alvd2w/askhistorians_uses_a_20year_rule_to_consider/
|
{
"a_id": [
"efhlf0t",
"efikb83",
"efjh8vg"
],
"score": [
84,
3,
3
],
"text": [
"There's not a hard and fast rule among universities or historians in general to consider events beyond a certain number of years \"history\" vs. \"current events.\" One only has to look at ~~Mao~~ Zhou Enlai's (probably apocryphal) comments on the effects of the French Revolution being too recent to analyze to see an example of this. \n\nThat said, we do have a 20-year rule fairly explicitly to avoid discussion of modern politics and modern events ... and as we inch closer to Jan. 1, 2021, we are semi-seriously considering extending the deadline to avoid 9-11 conspiracy theories. \n\n[This rules roundtable](_URL_0_) explains the reasoning behind the 20 year cutoff, both on the pragmatic side of things (we don't want to endlessly analyze every past US administration in the light of the current one) and the philosophical (at what point do we actually feel we have enough remove from a topic to engage with it).\n \nTo sum up, 20 years is *arbitrary*, but we don't think it's *capricious* in what can and can't be discussed, and it functions pretty well in keeping modern politics out of the subreddit. \n\nWith somewhat more than 900,000 subscribers and slightly less than 40 mods, we can only do so much in the time we're given, and removing modern debates lets us focus on, well, history. ",
"There is also a debate among historians that time does not really matter in the sense that doing history is a way of thinking about different topics. So the only thing that changes is the nature of the historical material that one must investigate. For example, newspapers are a very popular source for historians, or digital data, etc.",
"I don't know if I can answer this but I gotta congratulate this sub for implementing this rule. When one sees the debates at other social media or even other subs it's alarming how events just from 10 years ago still sparkle a lot of biased debate. ¿How could Obamacare be measured in just 8-10 years? ¿Can we really explain fairly the european migrant crisis? ¿How about even the post 9/11 world? It's going to be soon 20 years of 9/11 but I doubt the conspiracy theories will end anytime soon."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/45wqkl/rules_roundtable_5_the_current_eventsmodern/"
],
[],
[]
] |
||
9eglr7
|
why do toddlers prefer to run everywhere instead on walking? it doesn't matter if it's indoor/outdoor or what distance. the first option is to run to get from point a to point b.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9eglr7/eli5_why_do_toddlers_prefer_to_run_everywhere/
|
{
"a_id": [
"e5oqg0t",
"e5oqrka"
],
"score": [
3,
4
],
"text": [
"Well, if you have energy to burn, and are impatient as someone who's only got 2 or 3 years of being alive, it only makes sense to run.",
"They have the energy and impulse control isn't developed in their brains yet. Won't happen til closer to 4. That's why kids have to be taught o walk safely places in preschool and kindergarten."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2dbzng
|
Why is it that a SSD (Solid State Drive) will eventually decrease in performance after a long period of time, but RAM doesn't?
|
I was reading about Solid State Drives online recently and I have noticed a lot of people mentioning that SSDs do not have an unlimited usage as they will decrease in performance after constant writing of files, then I had a look at RAM. RAM works similarly, but needs a constant electric supply in order to preserve the memory. So what differentiates between SSD and RAM?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2dbzng/why_is_it_that_a_ssd_solid_state_drive_will/
|
{
"a_id": [
"cjohnx8"
],
"score": [
8
],
"text": [
"Two differences that contributes to write speed degradation:\n\n1) DRAM stores data as a charge in a capacitor. NAND flash used SSDs stores the data as a charge in a floating gate. In DRAM, the charges simply flow through the transistor into the capacitor. In NAND flash, writing requires tunneling electrons into the floating gate. This damages the insulation and eventually more time is needed to successfully write the bit. \n\nThe effects of NAND wear can manifest as higher error counts and SSD spare area decrease, both which can decrease SSD write performance. On the other hand, the difficulty in getting charges in and out of the floating gate is why SSDs are nonvolatile. DRAM must be refreshed constantly to keep the data which is why it needs a constant electric supply. The charge will leak out of the capacitor in the order of milliseconds.\n\n2) DRAM has a more fine-grained addressing mechanism. Current SSDs can only be erased in \"blocks,\" which is a large chunk of data. So in the course of usage, the SSDs controller will have to read a whole block, change data in a portion of the block in memory, erase the block, and then write. If fresh blocks are available, then it can skip the 'erase' stage and write the block. TRIM will try to minimize the churn involved in writing to a dirty block, but SSDs are always fastest fresh out of a complete wipe.\n\nFlash can be much more compact than DRAM because it lacks the extra circuitry needed for addressing. \n\nGenerally speaking, SSD write performance will quickly degrade upon first use after a clean wipe and remain stable until the end of the line."
]
}
|
[] |
[] |
[
[]
] |
|
71imyi
|
if atoms are over 99% empty space, how is it possible to create structures like spaceships that contain air and are airtight themselves while being surrounded by a vacuum?`
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/71imyi/eli5_if_atoms_are_over_99_empty_space_how_is_it/
|
{
"a_id": [
"dnayq78",
"dnayqyo"
],
"score": [
3,
2
],
"text": [
"Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5: I know that even though atoms are mostly empty space, we can't walk through walls because of electric fields, but if they're mostly empty, why isn't everything practically invisible? ](_URL_5_)\n1. [ELI5: If atoms are 99% empty space, and everything is made of atoms, what are we actually seeing when we look at something? ](_URL_6_)\n1. [ELI5: If atoms are 99% empty space, and if all matter is made up of atoms, why does solid matter appear ...well, solid? ](_URL_7_)\n1. [ELI5: How do we see objects if the atoms that make it are 99% empty space? ](_URL_3_)\n1. [ELI5:If atoms are 99.99% empty space then why some objects are solid? ](_URL_8_)\n1. [ELI5: If atoms are 99.99% empty space, why aren't objects mostly empty space? ](_URL_10_)\n1. [ELI5:Why if atoms are mostly empty space, we do not phase through matter. ](_URL_0_)\n1. [ELI5: If atoms are mostly empty space, how do we make impervious or waterproof things? Shouldn't atoms be able to get through? ](_URL_11_)\n1. [ELI5: If atoms are mostly empty space and don't even touch each other, why dont we just go right through? ](_URL_4_)\n1. [ELI5: if atoms are almost completely empty space and I am made up of atoms, then what is stopping me from walking through walls if the empty space lines up right? ](_URL_9_)\n1. [ELI5: If an atom is 99.99% empty space, why isn't all matter transparent, irrespective of density? ](_URL_1_)\n1. [ELI5: If all matter is primarily made up of empty space, how can a knife cut a tomato? And why can't my hand go through wood? ](_URL_12_)\n1. [ELI5: the reason why matter is solid, if the space between nucleus and electrons is so vast ](_URL_2_)\n",
"While yes, atoms are mostly empty space, remember how small atoms are. The space is orders of magnitude smaller than any molecule of air could fit through. "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/explainlikeimfive/comments/1ebd9w/eli5why_if_atoms_are_mostly_empty_space_we_do_not/",
"https://www.reddit.com/r/explainlikeimfive/comments/40mhaw/eli5_if_an_atom_is_9999_empty_space_why_isnt_all/",
"https://www.reddit.com/r/explainlikeimfive/comments/5btvyv/eli5_the_reason_why_matter_is_solid_if_the_space/",
"https://www.reddit.com/r/explainlikeimfive/comments/4e794w/eli5_how_do_we_see_objects_if_the_atoms_that_make/",
"https://www.reddit.com/r/explainlikeimfive/comments/3mt4o4/eli5_if_atoms_are_mostly_empty_space_and_dont/",
"https://www.reddit.com/r/explainlikeimfive/comments/3ak1z0/eli5_i_know_that_even_though_atoms_are_mostly/",
"https://www.reddit.com/r/explainlikeimfive/comments/3s0xzj/eli5_if_atoms_are_99_empty_space_and_everything/",
"https://www.reddit.com/r/explainlikeimfive/comments/26ohq6/eli5_if_atoms_are_99_empty_space_and_if_all/",
"https://www.reddit.com/r/explainlikeimfive/comments/3ig8id/eli5if_atoms_are_9999_empty_space_then_why_some/",
"https://www.reddit.com/r/explainlikeimfive/comments/2q8y7t/eli5_if_atoms_are_almost_completely_empty_space/",
"https://www.reddit.com/r/explainlikeimfive/comments/6sozkj/eli5_if_atoms_are_9999_empty_space_why_arent/",
"https://www.reddit.com/r/explainlikeimfive/comments/3xaeme/eli5_if_atoms_are_mostly_empty_space_how_do_we/",
"https://www.reddit.com/r/explainlikeimfive/comments/569hld/eli5_if_all_matter_is_primarily_made_up_of_empty/"
],
[]
] |
||
8yljle
|
Is there any historical documentation of the Viking Blood Eagle execution?
|
If so, do we know if this style of execution actually worked as intended?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8yljle/is_there_any_historical_documentation_of_the/
|
{
"a_id": [
"e2bvncl"
],
"score": [
4
],
"text": [
"More could be pried out of someone, but you might like to start with ['What are the chances the Vikings actually used the \"Blood Eagle\"? (previous highly rated answer has been deleted and other posts just link to the deleted answer)'](_URL_0_) by /u/mikedash .\n\nThis is not to discourage discussion. More questions, data, and debate are always welcome.\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/8temli/what_are_the_chances_the_vikings_actually_used/"
]
] |
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