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I find no reason to attach any significance to a dead body. Once you're dead, you're dead. Your body is just a rotting pile of matter, and to me, is no more important than trash or toxic waste. CMV. | Why is the desecration of a corpse considered by so many people to be a terrible crime? I can understand from a religious standpoint. But there are plenty of atheists and non-religious people who also believe that a dead person should be given a proper burial and we should "pay respect" to the dead, no?
Why? I understand proper disposal of a body from a health stand point, but are there any reasons to care about what happens to someone's body that are not based in religion?
Moreover, I don't believe necrophilia is such a morally reprehensible crime. To me it is no different than dendrophiliacs or that guy that was on /r/videos who has sex with cars. It's completely disgusting, and I would have concern for the health of someone who fucked a dead body, but I wouldn't have any negative feelings toward a person who did (at least from a moral standpoint).
I remember a while back there was a news story on /r/worldnews about U.S. soldiers pissing on the dead bodies of some Taliban soldiers (the details are a little hazy, but I think that was the gist) and so many people in the comments were outraged, many who were atheists. To me, that is like pissing on a tree.
I also remember a story earlier this year about a soldier/rebel in Syria who ate the heart of a dead enemy. It was reported as the worst atrocity yet from the war and people on reddit were disgusted by it. Apart from the health of the soldier eating the heart, I was not affected by the story at all. To me, torturing, murdering, and raping are far, far worse.
**TLDR; Is there any logical reason to care about a dead body?**
**EDIT/UPDATE: I made this post and then left for the day, so sorry I didn't have time to respond to you. Thanks for offering your perspective though. I think the main concern that everyone seems to agree on is for the living relatives/friends/loved ones. They naturally attach a certain sentimentality/symbolism to the body of their deceased family member. By paying respect to the dead, you are actually paying respect to those living loved ones. Even if it is based solely on religious beliefs, there is no reason to shit all over someone else's beliefs if they're not hurting you. That's pretty common sense. However, beyond the feelings of living loved ones, I still think a dead body is just that.** | 15 | It's not that we believe a corpse has intrinsic value, it's that it's hard enough for the family of the deceased to be burying a loved one, it just makes it easier for them to grieve if the remains are cared for. Many people, in their grief, would probably be upset to see mom, dad or little Jimmy's corpse fucked and butchered by some weirdo necrophile. Things like funerals and embalming are for the living, not the deceased. | 33 |
ELI5: The US Treasury has stellar creditworthiness, but it seems to always pay its debts by incurring more debt. So if paying debt with debt is no big deal, then why couldn't Greece do the same thing? Why did they have to default? | I'm an economics major but international finance fries my brain like an egg. Please help me understand. | 62 | Because Greece would be a *state* in the US, and especially in the US Economy.
The US incurs huge amounts of debt, but has the economy to cover its costs. Basically, the US is a guy who borrows $10million and makes $8million a year... and Greece is the guy who makes $50,000 and owes $2.5million.
Nobody would lend more money to Greece... they were already wobbling. The US is a lot stronger of an economy, so people are more than happy to keep throwing money at it. | 42 |
[MCU] Is Baron Zemo the perfect Antithesis to Ultron? | throughout the films, we see Ultron's obsession with making the human race superior while Zemo as we see in the later movies, hates the concept of super powered beings | 25 | Ultron wasn't specifically concerned about making humanity better. His plan was for his "meteor" to wipe out any life that wasn't strong enough to survive. Humanity would be tested against the meteor but if they died during or in the struggle afterwards then so be it, they simply weren't strong enough to deserve living - at least in his eyes. At a very basic level his beef with the Avengers was that they stood in the way of that kind of world-changing event from happening. Zemo's beef is that he sees the Avengers and their kind as the same type of world-changing event, at least in the sense that he believes they treaten the survival of humanity.
I'd say their core philosophies are almost directly opposed, but they also fundamentally disagree on where the Avengers fit in their worldviews. | 33 |
ELI5: Why isn't carbon absorption from forests and green space included when determining a country's contribution to global warming? | https://www.reddit.com/r/explainlikeimfive/comments/4ajzqv/eli5_why_isnt_carbon_absorption_from_forests_and/d117kkb
A nice explanation of how the UN does account for this when it is relevant. Thank you! | 295 | Because a forest, over the long term, *isn't taking or giving* any carbon back to the atmosphere.
Every part of the forest takes carbon *as it's growing*, but at any time, the amount of decay in a mature forest is equal to the amount of growth, which released that carbon back to the atmosphere. | 106 |
ELI5: Why is it considered disrespectful in most western countries to not remove your hat when going indoors. Also, why is it a sign of respect to remove your hat (I.e.- in old movies where men remove their hats and tip them to women)? What's the big deal about hats? | 25 | It is historically act of respect, originating from knights customs whereby the helmit of armour would be removed in civil company or to address lords/ladies and royalty (removing hat), it was also customary to raise the visor of the helmit on the battle field as a sign of respect to nobility or adversaries (hat tip, or military salutes) it still remains a western custom but has adapted over time | 48 |
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If we observe a star X light years away, does that mean theres nothing inbetween here and there obstructing our view? | 6,820 | There can be stuff in between, it just can't be enough to completely block out the star. We will often see stars as being "reddened" because of the dust and gas in our line of sight that blocks out part of the light. Stars can also be partially eclipsed by a planet moving in front of them, but planets are much smaller than stars and only block out a small fraction of a stars' light.
But yeah, generally space is very very empty, and you usually have a clean line of sight to most objects. The biggest issue is the dust and gas within the Milky Way - when we look straight along the plane of the Milky Way disc, we're looking through the thickest part of the disc, and all that dust and gas adds up and blocks out much of our own galaxy. | 3,570 |
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eli5: if nothing can move faster than light, do other things have to slow down when something moves close to it?? | Sorry if the title is confusing. Basically if I'm in a rocket ship and I begin to move away from Earth super close to the speed of light, and let's say the moon is moving in the opposite direction fast enough to make it so that I'm moving away from the moon faster than the speed of light, what happens? Do I simply move away from the moon faster than light? | 16 | No, this comes down to relativity. This has why time distortion happens. So it isn't that things slow down. It's that time literally passes differently for them than something moving at close to light speed. It then becomes a conversation about frames of reference. What one object looks like to the other with respect to time and vice versa | 24 |
ELI5: how does mesh wifi work and how is it different from old school extenders? | 670 | Wi-Fi devices like phones have a sort of tunnel vision to them. When you connect to a network, what your device is really doing is connecting to one specific access point that's emitting a Wi-Fi signal. Once your device has locked-on, it has a death grip on that signal. It WILL NOT let go of *that specific* access point until you either force it to disconnect, or the signal genuinely goes to zero and stays there for some time. While it's locked-on like this, your device will flat-out ignore every other access point in the vicinity, even if there are other ones nearby with stronger signals that it could switch to.
When you put an old school extender on your network, what you're really doing is putting a second access point on your network. That way, when your phone looks up and sees the Wi-Fi networks, it will see two separate signals--one from the original access point, and one from the extender. You pick whichever one has the best signal and now your phone is locked-on.
Let's say you are in the extender's range when you connect. Now your phone is locked onto the extender. But then you move about your house or office or whatever and now the signal to the extender is not so good. But the signal to the other one is great now! Your phone should switch over, right? WRONG. It's *locked-on*. Absolutely dead set on maintaining that death grip on the bad signal, unless you command your phone to drop it and switch over to the other one.
What a mesh system does differently is it essentially makes all the extenders wear funny masks that make them look exactly like the original access point, in a way that your device can't tell them apart. When you connect to one of them, they mutter amongst themselves and decide who is physically closest to you, and whichever one gets selected will reach out to your device and establish a connection. Then, as you roam about the area and go in and out of the ranges of all the mesh extenders, they silently and seamlessly hand over the job of talking you your device, as they can detect who is the closest to you at any given time.
Essentially, mesh systems work the way you probably *expected* extenders to work all along. | 1,859 |
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CMV:I Believe That The Letter of The Islamic Scriptures Describes A Geocentric Flat-Earth Model of the Universe | I must stress that i'm not trying to argue whether the texts should be taken literally or metaphorically on this. My argument is only about whether the letter of the Islamic texts describes a geocentric flat-earth model, as opposed to the scientifically accurate model.
I would summarize the model of the universe in the Islamic scriptures as follows: The Earth is flat. The sun is a smaller-than-the-Earth hot sphere that passes through the Earth when it rises and when it sets. The sun sets in a muddy pool or spring. The sky you see above is a solid ceiling and is in fact the lowest heaven, and by this I mean 'paradise' heaven. There are a number of layers of heavens above this lowest heaven, and they are all physically, directionally above us. God’s throne is physically above all the heavens. Also the stars/planets are little lamps affixed to the underside of the lowest heaven.
Below is a list of Quranic and Hadithic [1] verses, as proof for my claims. I shall include only verses from the Quran (Yusuf Ali English translation) and the Kutub as-Sittah (traditionally regarded as the set of strongest Hadith by Sunni Muslims).
1.[~ Quran 18:86](http://www.islam101.com/quran/yusufAli/QURAN/18.htm)
>Until, when he reached the setting of the sun, he found it set in a spring of murky water: Near it he found a People: We said: “O Zul-qarnain! (thou hast authority,) either to punish them, or to treat them with kindness.
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2.[~ Quran 18:90](http://www.islam101.com/quran/yusufAli/QURAN/18.htm)
>Until, when he came to the rising of the sun, he found it rising on a people for whom We had provided no covering protection against the sun.
Verses 1 and 2 refer to the Quranic story of Zul-qarnain , whose story greatly resembles the mythic tale of the Syriac version of the Alexander Romance [2]. In the Romance, Alexander the Great travels to the place of the rising of the sun (page 148).
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3.[~ Quran 37:6](http://www.islam101.com/quran/yusufAli/QURAN/37.htm)
>We have indeed decked the lower heaven with beauty (in) the stars
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4.[~ Quran 52:44](http://www.islam101.com/quran/yusufAli/QURAN/52.htm)
>Were they to see a piece of the sky falling (on them), they would (only) say: "Clouds gathered in heaps!”
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5.[~ Quran 34:9](http://www.islam101.com/quran/yusufAli/QURAN/34.htm)
>See they not what is before them and behind them, of the sky and the earth? If We wished, We could cause the earth to swallow them up, **or cause a piece of the sky to fall upon them**. Verily in this is a Sign for every devotee that turns to Allah (in repentance).
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6.[~ Bukhari 4:421](http://www.sacred-texts.com/isl/bukhari/bh4/bh4_425.htm)
>The Prophet asked me at sunset, “Do you know where the sun goes (at the time of sunset)?” I replied, “Allah and His Apostle know better.” He said, “It goes (i.e. travels) till it prostrates Itself underneath the Throne and takes the permission to rise again, and it is permitted and then (a time will come when) it will be about to prostrate itself but its prostration will not be accepted, and it will ask permission to go on its course but it will not be permitted, but it will be ordered to return whence it has come and so it will rise in the west. And that is the interpretation of the Statement of Allah: "And the sun Runs its fixed course For a term (decreed). that is The Decree of (Allah) The Exalted in Might, The All-Knowing.”
[Sahih Muslim 1:297-300](http://www.hadithcollection.com/sahihmuslim/129-Sahih%20Muslim%20Book%2001.%20Faith/8487-sahih-muslim-book-001-hadith-number-0297.html) are similar to the above verse.
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7.[~ Abu Dawud 32:4002](https://sunnah.com/abudawud/32/34)
>I was sitting behind the Messenger of Allah (ﷺ) who was riding a donkey while the sun was setting. He asked: Do you know where this sets ? I replied: Allah and his Apostle know best. He said: It sets in a spring of warm water (Hamiyah).
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8.[~ Abu Dawud 35:4705](http://www.hadithcollection.com/abudawud/267-Abu%20Dawud%20Book%2035.%20Model%20Behavior%20Of%20The%20Prophet%20(PBUH)/18398-abu-dawud-book-035-hadith-number-4705.html)
>Narated By Al-Abbas ibn AbdulMuttalib : I was sitting in al-Batha with a company among whom the Apostle of Allah (pbuh) was sitting, when a cloud passed above them.
The Apostle of Allah (pbuh) looked at it and said: What do you call this? They said: Sahab.
He said: And muzn? They said: And muzn. He said: And anan? They said: And anan. AbuDawud said: I am not quite confident about the word anan. **He asked: Do you know the distance between Heaven and Earth? They replied: We do not know. He then said: The distance between them is seventy-one, seventy-two, or seventy-three years. The heaven which is above it is at a similar distance (going on till he counted seven heavens). Above the seventh heaven there is a sea, the distance between whose surface and bottom is like that between one heaven and the next. Above that there are eight mountain goats the distance between whose hoofs and haunches is like the distance between one heaven and the next. Then Allah, the Blessed and the Exalted, is above that.**
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9.[~ Bukhari 19:1145](https://sunnah.com/bukhari/19)
>Narrated Abu Huraira:
Allah’s Messenger (ﷺ) (p.b.u.h) said, **“Our Lord, the Blessed, the Superior, comes every night down on the nearest Heaven to us when the last third of the night remains,** saying: "Is there anyone to invoke Me, so that I may respond to invocation? Is there anyone to ask Me, so that I may grant him his request? Is there anyone seeking My forgiveness, so that I may forgive him?”
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I will deal with a few rebuttals below:
I.[This IslamQA article](https://islamqa.info/en/118698) explains that the consensus among Muslim scholars is that the Earth is round, but as far as I can tell, it only gives this verse as evidence:
[~ Quran 39:5](http://www.islam101.com/quran/yusufAli/QURAN/39.htm)
>He created the heavens and earth for a true purpose; He wraps the night around the day and the day around the night
The above verse is however, vague. Even if this does hint at a round Earth model, it has to contend with all the other verses I’ve provided above.
II.[This IslamQA article](https://islamqa.info/en/88746) deals with the verse under the numbered heading, “8″. The article argues that the Hadith verse is weak in authenticity.
Even if it follows that the Hadith is weak, there are many other verses that point towards the erroneous model. Some of these erroneous verses are from the Quran, which is regarded by Muslims as infallible.
III.[This IslamQA article](https://islamqa.info/en/176375) argues that because we know the world is round, we cannot possibly tell what the Hadith is really about. The problem with this sort of argument (i.e. we can't possibly know what the text really means) is that it can be used to dismiss any errors that may turn up in any text.
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[1] Hadith are reports of the Prophet Muhammad's sayings and actions. Authentication of hadith are a major field of study in Islam.
[2] ~ Syriac version of the Alexander Romance (page 148)
>So the whole camp mounted, and Alexander and his troops went up between the foetid sea and the bright sea to the place where the sun enters the window of heaven ; for the sun is the servant of the Lord, and neither by night nor by day does he cease from his travelling. The place of his rising is over the sea, and the people who dwell there, when he is about to rise, flee away and hide themselves in the sea, that they be not burnt by his rays ; and he passes through the midst of the heavens to the place where he enters the window of heaven ; and wherever he passes there are terrible mountains, and those who dwell there have caves hollowed out in the rocks, and as soon as they see the sun passing [over them], men and birds flee away from before him and hide in the caves, for rocks are rent by his blazing heat and fall down, and whether they be men or beasts, as soon as the stones touch them they are consumed. And when the sun enters the window of heaven, he straightway bows down and makes obeisance before God his Creator ; and he travels and descends the whole night through the heavens, until at length he finds himself where he rises.
There are other clues that point to the Quranic Zul-qarnain being derivative of the Alexander Romance, which are the inclusion of Gog and Magog, and the reference to Alexander as the “two-horned one” in the Romance, which translates to “ Zul-qarnain”.
| 22 | "He went towards the setting of the sun" just means "He went westwards". It's a poetic way of looking at it.
For many other points, it's important to bear in mind that this is a religious text. So when it says 'Heaven' it's really talking about Heaven. The place that is above us morally, not physically. Cosmology doesn't disprove any religion when it examines the sky and fails to see the afterlife there.
This comes to the main issue. The writers of the Quran could easily have been aware of the nature of the solar system. They might have known about evolution and quantum mechanics too. But as they had been revealed the very nature of Allah and the spiritual nature of existence, it wasn't a priority for them.
Trying to learn cosmology from the Quran is like trying to learn biology from a washing machine manual. It can use biological washing powder, but the text is about something different. | 13 |
[LOTR] What Happened to Erebor after the battle? did anyone take over? What happened to the remaining Dwarves and what happened to the treasure? | 26 | With the deaths of Thorin, Fili and Kili, Dain inherits the throne. The Dwarves resettle Erebor and Men resettle Dale under the rule of Bard.
During the War of the Ring both cities are seiged. Although they eventually beat back the attackers, Dain and Brand (Bard's grandson and current king of Dale) die. | 19 |
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CMV: The blue pill is an impossible choice to make. | First off, I'm strictly talking about the choice in the matrix and the hypothetical presented in the movie, not any topic or issue that has adopted red pill blue pill language since the movie came out.
So the situation: you are offered a choice between taking the red pill, and "staying in Wonderland" and learning more about the truth of what your reality is and is not. Or take the blue pill and "wake up in your bed and believe whatever you want".
This hypothetical is often presented to people and ask if you are a red pill r or a blue pillar. Its similar to asking if you believe ignorance is bliss and would you rather not know an unpleasant truth.
But my view, is that even presenting someone with the situation already makes the choice for them. By presenting the question you are informed that your world is not real. There is no way to leave "wonderland" only not go deeper.
Going further specificly with the details of the movie, neo has already been presented with direct evidence showing that the world is not what he thought. He can't just wake up the next day and believe whatever he wants, he already knows some truth that can't be unknown.
I would also say this doesn't include a memory wipe. Since that isn't actually mentioned by morpheus | 94 | We know from the red/blue pill scene what the pills actually _are_ - they appear as pills in the Matrix, but they are actually code injections into the person taking the pill. This is confirmed by Morpheus shortly after Neo takes the red pill; he states that it was a bit of code to disrupt his connection with the Matrix, allowing them to remove him from the simulation and locate him in the body farm. While not explicitly stated, it is reasonable to assume that the blue pill also contained a code injection.
We also know that memories of "reality" can be manipulated in the Matrix. Smith does this after Neo is implanted with the tracker - Neo wakes up in his bed assuming that the scene with Smith was a dream. He confirms this in the car when the tracker was removed, saying something like "You mean that shit was real?!?"
Based on those two events, we can _reasonably_ assume that the blue pill would inject code similar to what Smith used - Neo would wake up in his bed and assume that the meeting with Morpheus was just a dream. If Neo chose that route, it seems likely that Morpheus would never contact him again - the red/blue pill choice was a one time offer from them, and taking the blue pill would "end his story".
Now, Neo would probably still have that suspicion in the back of his mind that the Matrix was real and reality was fake, but he would never again get the opportunity to confirm that, as no one would ever reach out to him again with a similar offer. He would just be another closet conspiracy theorist, believing what he wanted but never getting any opportunity to prove it. | 96 |
What stops fruits & veg like tomatoes from cooking on the plant during hot days? | If I put a tomato in the oven at around 30 degress celsius for 10-12 hours, it will become somewhat mushy and the skin might separate from the insides. It will be cooking and never return to the state it was before I placed it in the oven.
Why doesn't the tomato cook on the plant during a hot day? and how is the tomato "normal" again when I check the plant later, on a cooler day? | 15 | Damage is done to the plant from the heat on hot days, the difference is that when the fruit is still on the plant it has the opportunity to repair itself.
Just like you might not expect a severed human hand to heal a burn, neither will severed parts of many organisms. | 12 |
CMV: Software should not be patentable. | I am a professional Software Engineer working for some of the big boys in the software field.
Software should never be able to be patented (just Copywrighted) this includes software algorithims
* Most software algorithms are not non-obvious (Shopping cart, sorting a deck of cards)
* Software Algorithms for more complicated stuff (Compression Algorithm, communication standards etc etc) are also obvious to people in the field. (JPEG compression concepts are well understood by anyone who knows anything about compression (DCT, Run-length encoding etc etc) the only thing that should be protectable is the final product.
* It doesnt give a meaningful edge to any company other than to extort and complicate the creation of new products.
* most meaningful software used is open sourced, what companies pay for is the specialized tailoring that is done to build a custom application; again your product is protectable by copyright not patent. | 54 | Is shopping cart really obvious?
Internet was not originally designed for persistent states. So originally on-line shopping was a real engineering problem.
First shopping carts involved a clever use of cookies to persistently store user selections as he browses around different pages on the site. Why do you think this was obvious?
Similarly, Amazon's infamous "single click" patent did something that no one was doing before - used stored profile data to instantly check out customers without the need to walk a customer though tedious shopping cart menus.
Why shouldn't the engineers who came up with these creative solutions to real problems not be entitled to patents?
edit: spelling, grammar | 15 |
ELI5: How does the body know when to wake up from sleeping? | 23 | We are all subject to a circadian rhythm which dictates our sleep timings. A couple of factors include exposure to light and our body's release of supplement called melatonin.
Many babies, for example, are naturally nocturnal. That is why parents have to sleep train them. After that, they will typically get tired and wake up around the same times each day.
Of course, this circadian rhythm varies depending on the person.
This is also why when you wake up naturally, (as opposed to alarms or other noises) you often feel more rested, no matter how much or little sleep you got. | 10 |
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ELI5: Why Napster got sued but UTorrent and others are still fine? | 481 | Napster was one centrally located server whereas utorrent is just an application that you use to connect to any of the millions of torrent tracker servers out there. It's as if there are millions of Napsters out there now instead of just the one. And those DO get shut down, it's just that there's so many of them and when one gets shut down, another 5 pop up to replace it.
On top of that, the uTorrent application is perfectly legal, it's what can be downloaded using it that is illegal.
TL;DR - Decentralization. | 520 |
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What would be the consequences for a female Chihuahua if she would get impregnated by a Saint Bernard? | 40 | The mother Chihuahua can only supply the Saint Bernard fetus with a finite quantity of nutrients, due to her smaller stomach, smaller digestive tract, etc. Therefore the puppy will be stunted, a runt compared to ordinary Saint Bernard puppies, although at the maximum size of puppies that a Chihuahua can carry. The birth itself might be risky, but not ludicrously out of proportion. The puppy would probably regain a good deal of its normal size if allowed to nurse elsewhere. | 32 |
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[Oblivion] I'm strolling around the magic university completing tasks relating to ending Necromancy around Cyrodiil. Following me is my faithful reanimated skeleton, Spooky. Why am I not kicked out of the guild on the spot? | 29 | The fact that the creation is undead doesn't change the fact that the summon spells are just plain old conjuration, drawing things from other planes or simply thin air by the power of your magicka. You're not desecrating a corpse or playing with peoples' souls; as far as the Guild is concerned, it's not necromancy at all. | 44 |
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[Predator] I'm just a regular soldier being hunted by a Predator. If I drop my weapons, fall to my knees and beg for mercy, would the Predator let me live? | I'm not a special forces soldier/super badass, I'm just a regular grunt pulling guard duty around the base. So do I have to be holding a weapon and actively fighting against him for the Predator to kill me or can I just surrender and hope he lets me go? | 28 | Have you opened fire yet, or otherwise taken action against them?
If you haven't already made hostile contact with them, there's a decent chance you can ditch your rifle and hotfoot it out of there. If they're an experienced hunter (and they shouldn't be fucking around with Soft Meat if they aren't), and you don't accidentally flee straight into their perch, they'll likely let you go so they can focus on real opponents. Human kills have nothing to do with just getting a skull for the raw pleasure of owning a skull, it's all about *the story*. Humans backed into a corner do *crazy shit*, and that's the whole reason hunting them is worthwhile. No pred wants to point up at a skull on their trophy wall and say "Yeah, bagged that one while he was taking a shit, stabbed him with a spear right through the outhouse wall".
If you've already pulled the trigger? You're probably fucked, since you're counting on the pred to correctly interpret your action as fleeing the scene, versus fleeing to get a bigger gun and ditching your current gun so you can run faster. Perhaps they're feeling generous and let you bolt, perhaps they put a plasma caster round into your back, perhaps they want to gut you so your comrades who held their ground can listen to the sweet, demoralizing sounds of your guts being slowly removed. It's a crapshoot. | 77 |
ELI5: Why have it taken so long to prosecute former Nazi's, that we still see cases popping up today? | 5,619 | There are a few reasons. A lot of former Nazis hid their identities and escaped to countries where they were not easy to identify, such as Argentina. However, the main reason for the recent prosecutions is that Germany changed what had to be proven to convict someone. Between 1949 and 1985, there were 200,000 investigations and 120,000 indictments of former Nazis in Germany, but less than 7,000 convictions. Those convictions required that a prosecutor prove a person's role in a specific murder.
The German government changed its policy on Nazi war criminals around the year 2000, allowing prosecutions of Nazis who served in death camps or mobile killing units, based on their service alone, and not their role in any specific murder. As a result, former Nazis would couldn't be convicted before can be convicted now.
So a number of people who were investigated and cleared are now being prosecuted because of this lower burden of proof. As far as identifying former Nazis who escaped, that happens at an increasingly less frequent rate because the majority have died at this point. | 4,909 |
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ELI5:Why does China only have one timezone? | Surely being the size of the US would mean the sunrise and sunset occur at very different times across China. | 179 | Mao Zedong and the Chinese Communist Party moved to a single, nation-wide timezone in 1949 to help promote a sense of unity in the country. It does present the problem you pointed out, which is that daylight does not correspond to the same hours everywhere across the country. This is most pronounced in Western China, where there are also separatist populations that still use the local time rather than Beijing time. | 121 |
ELI5: Why does fertilizer explode? | 22 | Most fertilizers contain ammonium nitrate.
Ammonium nitrate is an oxidizer that reacts with other combustible materials.
Normally it's fairly safe to have around at normal temperatures. But when it's heated up to higher temperatures, or exposed to a hot fire, a run-away chain reaction can occur with ammonium nitrate to cause a violent explosion.
It's often used for improvised explosive devices, and for accelerating the reaction of other explosives, such as in some forms of dynamite. | 14 |
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What is the psychology behind the "duck face" phenomenon? | Not its spread through social media, but the impetus to appear this way in the first place. | 25 | Makes cheekbones look more defined, face look thinner, and lips look fuller.
Lots of women (sometimes without realizing) do it to a lesser extent to put emphasis on these features. It probably just got out of hand after a while. | 63 |
[Star Trek]How strong is the Federation fleet, really? | The only really good view we get of federation multiship combat comes from snippets of Borg battles, combat scenes in Enterprise, and the few episodes of DS9. In any of the mirror episodes, it seems like the Federation gets its ass handed to it quite regularly by other Alpha Quadrant powers, whether it be Klingon, Romulan, or even the Xindi. Hell, the Dominion should have taken over the Alpha quadrant, if not for timely interruption by the founders. So my question really is: is the federation really a military force to be reckoned with against other military powers? Do they actually have an edge on any other super power? Or is it just a matter of peace due to no one wanting to rock the boat. | 53 | The Federation *fleet* is on par with, or slightly weaker than, most other Alpha Quadrant powers. They maintain the bare minimum amount of force necessary to protect themselves from unexpected hostilities, and devote the rest of their resources to scientific exploration, pleasure, art, etc.
Federation *theoretical military capabilities* are more powerful than every other faction in the alpha quadrant combined. The other aggressive alpha quadrant powers (Romulans, Klingons, Cardassians), are a fraction of the size of the Federation and don't have *nearly* the technological ability. They maintain something resembling military parity by devoting the whole of their industrial base to military production. They sacrifice aesthetics, quality of life, and democratic freedoms to do so.
For example, both the Cardassians and Klingons still use *slaves*. There's no logistical reason to even need to do so, they just lack so much respect for their citizens lives they they ensure a number of them toil away.
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So, if the Federation were willing to militarize, it would be an unstoppable juggernaut, capable of steamrolling the rest of the quadrant, and standing on equal footing against the Founders.
- It doesn't militarize against the existing powers because that would require compromising Federation values.
- It doesn't successfully militarize against the Founders because it doesn't have quite enough time to succeed. The entire war takes place over only a few years, and federation planners anticipated being able to drag out any conflict with known enemies by a decade or longer.
- The Borg are a special case. Federation scientists work exhaustively for innovative, rather than brute force solutions. | 64 |
ELI5: What's the difference between antihistamines and decongestants? | 76 | People sometimes (inaccurately) use them interchangeably but antihistamines are specifically for allergies. Histamines are compounds related to immune system response, and allergies are caused by hypersensitivity of the immune system.
Decongestants are just drugs that treat nasal congestion in the upper respiratory tract, which might be caused by allergies but could be lots of other things too.
If you just look at the labels on the drugs, you'll see the active ingredients are different. Some products might be a combination of the two, but it's just two different drugs mixed together. | 70 |
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ELI5: Why would the U.S. Armed Forces test a missile like the one seen last night so close to a heavy populated city? I understand it was not armed, but they had to know it would be mistaken for a UFO or other threat. | Also, to any ballistic experts or veterans, what kind of missile was that? It's large blue appearance is just odd to me. | 86 | It was a Trident II missile.
The large blue appearance has nothing to do with the type of missile. Rather, it has to do with the time of launch (shortly after sunset, IIRC). High up, the sun was still above the horizon, and lit up the exhaust gasses. | 63 |
If a flying insect hitches a ride on my windshield for a mile or two, does it find its way back home or does it start a new life when it leaves my car? If the latter, how does it integrate into a new ecosystem? | 554 | Most species of insect don't really have a "home," just wherever they happen to be at the moment. Spiders and other species that do construct a more permanent burrow will build a new one.
The ecosystem of two miles down the road is probably roughly the same as where you were before, so it'll be fine. | 242 |
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ELI5: Tax returns are the return of excess wages that the government in a sense loaned from us. Why aren't we entitled to interest on the excess tax? | 22 | Because you decided to withhold more money than you owed in taxes which is not the government's fault.
And the government makes the laws and they chose not to give you interest - and even if you did it'd probably be at most single-digit dollars. | 22 |
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I always feel really depressed and low after a night of drinking. What exactly is alcohol doing to us when we drink, and how long does it take the effects to wear off? | 141 | Psychology major here.
Depressants are a class of drugs that depress or inhibit central nervous system activity. In general, depressants produce drowsiness, sedation, or sleep. Depressants also relieve anxiety and lower inhibitions. All depressant drugs are physically addictive. Also, the effects of depressant drugs are additive, meaning the sedative effects are increased when depressants are combined.
In the case of Heath Ledger he was found to have multiple prescription drugs in his body, including two kinds of narcotic painkillers, two kinds of anti-anxiety drugs, and two kinds of sleeping medications. None of the legally prescribed medications had been taken in excess. Even so, the combination produced a lethal additive drug effect, depressing his brain's vital life functions to the point that respiratory failure occured.
Generally, it takes about one hour to metabolize the alcohol in one drink, which is defined as 1 ounce of 80-proof spirits, 4 ounces of wine, or 12 ounces of beer. Factors such as body weight, gender, food consumption, and the rate of alcohol consumption also affect blood alcohol levels. A slender person who quickly consumes three drinks on an empty stomach will become more than twice as intoxicated as a heavier person who consumes three drinks with food. Women metabolize alcohol more slowly than men do. If a man and a woman of equal weight consume the same number of drinks, the woman will become more intoxicated.
As far as how alcohol affects the body, it depresses the activity of neurons in the brain. Alcohol impairs cognitive abilities, such as concentration, memory, and speech, and physical abilities, such as muscle coordination and balance. As blood levels of alcohol levels continue to rise, death can occur because the brain's respiratory center can no longer function.
As far as alcohol withdrawal symptoms, it causes *rebound hyperexcitability* in the brain. The severity of the withdrawal symptoms depends on the level of physical dependence. With a low level dependence, withdrawal may involve disrupted sleep, anxiety, and mild tremors, colloquially known as *"the shakes"*. At higher levels of physical dependence on alcohol, withdrawal may involve confusion, hallucinations, and severe tremors or seizures. Collectively, these severe symptoms are sometimes called *delirium tremens* or the the DTs. In cases of extreme physical dependence, withdrawal can cause seizures, convulsions, and even death in the absence of medical supervision. | 45 |
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[Harry Potter] Do wizards have some form of wizard MMA? | Yes; we know dueling clubs aren't uncommon but quidditch seems to be the only popular sport; and some as interested in sports and dada as Harry would have probably taken note of it. | 24 | In the UK it appears they don't. Why should people hone their bodies when magic is enough? If you're in a situation where you don't have your wand against another wizard then you're screwed anyway. It's very unlikely that you'll both be without a wand and even so, wordless magic is still a thing. If you have to prepare to be in that predicament, then apparating is more efficient and practical. | 14 |
ELI5: What is Socialism? And why do people think America is coming to that? | I keep hearing that Obama is making America socialist. I'm sure I learned what it was back in grade school but do not remember what it is exactly. And is it really that bad? | 15 | It's maybe worth saying in addition to the responses you've had, that *nobody* at all, outside the US, thinks that America is going socialist.
That some Americans think they are, is pretty funny and the result of what Europeans, in various languages, used to call propaganda. Of course there's no such thing as propaganda in the States. That would be ridiculous. | 31 |
ELI5: How do modern day 'hackers' learn to do what they do best? | It seems everywhere I go you can see news clips about someone who has 'hacked' into a major system or found a new way past some firewall. I know it's not as it's depicted in movies, and programming language is an important pre-requisite, yet nowhere i look can you find a starting point or decent program for someone interested in doing it.
EDIT: Thank you for all of the replies, i appreciate it. Now I've been surfing around some threads and what not, lo and behold i'm learning something bout programming. | 49 | How do they learn? Trial and error and spending a lot of time analyzing even the most asinine elements. Looking at what others have built and seeing "patterns" hacking is basically software engineering but in reverse. So really ANY software class/textbook is a good place to start. | 24 |
[MCU] what happened on Titan to make its gravity so wonky? | I can only assume it was the result of some sort of superweapon deployed at the end of their resource war | 32 | Pre-collapse Titan had massive hovering structures. Maybe they were messing with gravity on the planet, resulting in it going weird when the societal collapse came and the technology could no longer be maintained. | 34 |
ELI5: Why do surface wounds like paper cuts hurt or sting so much, especially compared relatively to other wounds? | 33 | The above answers (more nerves on your hands/near the surface) are true but another reason that papercuts specifically hurt so much is because the edges of paper are really ragged microscopically (think Velcro), so when you get a papercut it does more damage to your skin cells than if you nicked yourself with a sharp knife. | 31 |
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Is the Oortcloud (est 0.03 to 3.2 ly) shared with other stars, ex Alpha Centauri (4,36ly) ? | I pictured the oortcloud as a far flung region of stuff loosely affected by the sun. But since it seems to stretch so far out that parts actually are closer to other stars wouldn't that make it shared? Or does it refer to the region of interstellar comets that are affected by our sun? But Doesn't the Alpha Centauri system have a higher mass than our sun shouldn't it be more affected then?
​
Or doesn't this have to do more with he fact that stars aren't static and are moving relative to each other so that the Oort cloud are "our" comets and they have theirs but since the distances are so huge and we aren't necessarily very close for too long it doesn't matter too much? | 32 | By definition, the outer limit of the Oort cloud is defined by where the gravity of our solar system predominates. It's not a sphere. The competing gravity sources are nearby stars (such as Alpha Centauri), and the whole Milky Way. But the mass of Alpha C is only 0.123 solar masses, so even in that direction you have to go out to 3.23 ly before Alpha C's gravity is stronger.
The question of whether an object is part of the Oort cloud depends on it's distance and dynamics. If it's going fast enough, a close-in object will escape, so it's not part of the cloud. | 20 |
ELI5: Sim City game server problems after release (and previous Diablo 3 problems). Why they just can't buy additional servers at launch and when peak is over cancel them? Everyone's heard about cloud computing, EA hasn't? | 60 | These kind of problems aren't necessarily solved by throwing more servers in the mix. Chances are they have plenty of computing and bandwidth resources to cope with the current demand. The issue is that with the release of any new system, the first time it is in a real production scenario, bugs and other logistical issues may arise that weren't apparent during more controlled testing. | 14 |
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ELI5: Why does the price of everything keep going up? | 437 | Central banks, more or less, have control over how much money is in circulation and also have a fairly good idea of the amount of stuff produced and services provided. As such, modest inflation, and thus increasing prices, is a policy choice.
The reason why is that it incentivizes investment (why hold cash instead of spending it or lending it to someone with a productive use for it if it will decline in value over time?) and helps avoid deflation (decreasing prices), which creates a feedback look sapping investment and spending (why spend your money now when it will be worth more later?). | 417 |
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ElI5: What made the big bang occur? | ELI5 What events allowed the big bang to occur. Thanks! | 21 | This one's easy:
We don't know.
ts;dr: It might not even be a valid question, since time probably didn't exist at all, or in any meaningful way like it does now. So the idea of cause and effect can't exist either, without time.
| 46 |
[Kingdom Hearts] Are the terms Heartless and Nobody backwards? | So the weird shadowy monsters are manifestations of hearts and are called "heartless", while the spindly gray things/Hot Topic dudes are empty bodies called "nobodies".
Shouldn't the thing with a heart and no body be called a "No-body" while the thing with a body and no heart be a "Heart-less"? | 21 | The names were picked (in-universe, even) to be a little ironic. What do you call beings that are made of hearts, but only out of the darkness within them? We'll call them Heartless, because that's what they represent, even though they're made from hearts. What do we call beings that are made of the bodies left behind, but which lack the feelings and identity that a heart brings along? Let's call them Nobodies, because despite being all body, they really are nobody. Ansem had a sense of humor.
Of course, they weren't the ones who named the Unversed, so those dudes got a more literal name, being things that were made from pure emotion without any ability to think or identify themselves. | 17 |
CMV: We would have a more informed populace if schools prioritized statistics and probability over other areas of math | **Constraints**
First, my primary education in the US public school system in the pre-Common Core days. I took a quick glance at the [Common Core curricular content](https://en.wikipedia.org/wiki/Mathematics_education_in_the_United_States), and it looks very similar to what I had to learn. My understanding is that before CC, curricula were more varied by state, but for the sake of keeping the discussion focused, I will be focusing on CC Standards in the US.
Second, I majored in a STEM field that was fairly math-heavy, and while I don't believe that much of it is useful to me today, I'm not ready to make this claim for all majors. So I will focus on primary education and leave universities out of this.
**My View**
As per CC Standards in the US, basic math education consists of Algebra I, Geometry, and Algebra II. College-bound students are also offered Pre-Calculus, Calculus, and "other optional mathematics courses \[...\] such as statistics or business math".
One of the age-old questions that students ask is, "When are we ever going to use this?" While I'm not here to argue that these skills are useless in adulthood, I think they are vastly overrated. [This article](https://www.forbes.com/sites/jamesmarshallcrotty/2012/12/06/when-am-i-ever-going-to-use-algebra-the-real-world-utility-of-classroom-learning/#36fe2bfd6bfc) has some examples of ways we use certain subjects every day, and some of them, like using algebra when calculating purchases, are very reasonable. However, to reference another one of its examples, I'am not convinced that one needs a solid understanding of calculus to pay off their debt, especially with the prevalence of apps and online calculators today.
What I do believe, is that we benefit from a solid understanding of statistics everyday. Gaps in people's knowledge of statistics have long been exploited by advertisements, political campaigns, and unscrupulous con artists. Given the tumultuous current events right now, a fundamental grasp of statistics is necessary to make sense of two or more conflicting sources, particularly when they present conflicting interpretations of the same data. Without knowing how to determine statistical significance of the numbers we see in the news, or in commercials or opinion pieces, it is very easy to fall prey to someone's agenda, and this may result in wasting money, spreading misinformation, or making life decisions based on faulty, inconclusive, or erroneous data. If these decisions concern one's health, they may even be life or death decisions.
At the very least, I think the emphases on statistics and calculus in the American school system should be swapped, and an leaning towards spreading it out over multiple years, de-emphasizing the importance of Geometry, Algebra II, Pre-calculus, and Calculus in favor of a more rigorous statistics education. I am not ready to say that it is more important than Algebra I.
**What would CMV**
A convincing argument as to why Algebra II, Geometry, Precalc, and/or Calculus are more important for day to day life than statistics, or an argument as to why statistics are not as important as I have claimed.
**What would not CMV**
Anything about standardized tests. I am operating under the assumption that tests should resemble education, and not the other way around (it doesn't always work that way, but that's a discussion for another time).
Anything differentiating probability and statistics. While they are often bundled together, I realize I didn't state that clearly. But from here on out, let's lump them in together as being equally important.
I also think that for the sake of "not getting duped" (to summarize what I wrote earlier), understanding the rules of logic and critical thinking are just as essential as statistics, if not more so. This should be taught alongside probability and statistics, but for now, I want to focus on the importance of prob/stat vs. algebra/geometry/precalc/calc. | 159 | The reason why Algebra II, Geometry, Precalc, and Calculus are more important to do first is that _they are prerequisites for Statistics_. You fundamentally can't do Statistics with any sort of continuous random variables without either Calculus or lying extensively to students about what terms mean. For example, the expected value, which is a central concept essential to basic statistics, literally _is an integral_ (in its simplest formulation) and can't be properly explained without integration. | 64 |
[Loki] Why don’t all Loki variants look the same? | Maybe I’m missing something big, but don’t all variant Loki’s come from the Sacred Timeline? We’ve seen different Loki’s in the show so far, and all of them have looked very different from each other. We know that Sylvie has a different backstory than the Loki we know. How come she wasn’t taken by the TVA as soon as her life differed from Tom Hiddleston’s Loki? Wouldn’t any small changes to Loki’s life (like him being a crocodile) cause a nexus event? Also does the fact that there is only one Sacred Timeline conflict with the Doctor Strange movie, in which the Ancient One shows Strange the multiverse? | 27 | The Simple explanation is that the Sacred timeline isn't just a single timeline its a collection of timelines that work in the favor of whoever is controlling the TVA
so basically Sylvie wasn't arrested because she was a female loki coz if that happened she would have been taken as a newborn her nexus event was that she was good
Basically the sacred timeline also has a timeline where there is a female loki | 42 |
[Discworld] What would happen is you used the Warlock's Wheel on the Disc? | http://tvtropes.org/pmwiki/pmwiki.php/Literature/TheMagicGoesAway | 37 | Depends on the size of the wheel. Thing is, Discworld also has Narrativium, which would assuredly not allow the wheel to function for very long since it would wind up destroying the Disc in a decidedly underwhelming manner. Belief is also an extremely powerful force on the Disc - it is entirely possible that the world would be held together by the sheer ego of the UU faculty, who hold wizardliness as part of their very being.
Ironically, it would be the witches who would step up to the plate to destroy the device, since their two bastions of strength - headology and understanding of Narrativium - don't require any conventionally measurable magic of the Disc to function. Weatherwax would just stare at the wheel until it gets embarrassed at how childish it's acting and stops.
Edit: There's a more horrifying way for the Disc to defend itself, if the wheel does not destroy it in nine months. Once wizards identify this void of magic, the first thing they would do is revoke the celibacy rule. A wizard squared - an eighth son of an eighth son of an eighth son - is a sourcerer - a walking source of magic in his own right. Coin was strong enough to trap the gods and even enable Rincewind to use magic. A single sourcerer saturated the world with enough magic to plunge the Disc back into the wizarding wars, which were, from Rincewind's description, close enough to being caught in a reality warper conflict.
>The wizard shook his head gloomily, and picked up a pebble. He tossed it up above the ruined wall, where it turned into a small blue teapot. It smashed when it hit the ground.
>'The spells react with one another,' he said. 'There's no telling what they'll do.'
...
>The battle of Al Khali was a hammer-headed cloud, in whose roiling depths weird shapes could be heard and strange sounds were seen. Occasional misses seared across the city. Where they landed things were ... different.
>For example, a large part of the soak had turned into an impenetrable forest of giant yellow mushrooms. No-one knew what effect this had on its inhabitants, although possibly they hadn't noticed.
>The temple of Offler the Crocodile God, patron deity of the city, was now a rather ugly sugary thing constructed in five dimensions. But this was no problem because it was being eaten by a herd of giant ants.
>On the other hand, not many people were left to appreciate this statement against uncontrolled civic alteration, because most of them were running for their lives. They fled across the fertile fields in a steady stream. Some had taken to boats, but this method of escape had ceased when most of the harbour area turned into a swamp in which, for no obvious reason, a couple of small pink elephants were building a nest.
I think the sourcerer containment policy might actually destroy the Disc before the wheel is able to. | 28 |
I believe that falsely accusing another person of rape with the intention of defaming that person should be a felony. CMV | The damage done to the wrongly accused is often terrible and irreparable. When one is accused of rape, they are often treated as if they are guilty before ever seeing a courtroom. They are often divorced by their spouses. They often lose their jobs, and they are often vilified by their friends and peers. Accusing another person of rape can in many cases ruin that person's life.
When somebody accuses another of rape as a way to harm or intentionally defame that person it makes people more skeptical of actual rape victims. Obviously when somebody claims they were raped, everyone must take the accusation very seriously. Rape is one of the worst crimes a person can commit, IMO, and rape victims should be immediately trusted and accepted instead of doubted and questioned. False rape claims wrongfully perpetuate the idea that rape victims are lying about the crime or simply exaggerating.
I know someone who was falsely accused of rape. The supposed "victim" was caught in a series of lies and eventually admitted to accusing the other person of rape as a way to get back at them for some past event. So far, the accuser has seen no discipline. Please change my view. | 150 | I think the problem with this is the idea of proof beyond a reasonable doubt.
When someone is accused of rape, and acquitted, that doesn't automatically mean that the person that accused them of rape was lying. It could be that the person *did* rape them, and everyone knows it, but there wasn't evidence beyond a reasonable doubt to prove it.
Proving that someone intentionally lied about someone raping them is a whole separate issue from proving if they were raped in the first place. They have to be treated as two separate cases. You can't automatically assume that if one person is found innocent of rape, then their accuser should be found guilty of lying about the rape.
Unless the process is handled *very* carefully, it could serve as another barrier in preventing legitimate rape victims from reporting the crime. If they feel that they could actually be thrown in jail for being a rape victim if the rapist has a better lawyer than them, they might be too afraid to report the crime.
Your idea sounds like a relatively good idea in theory, but how would you implement it in a feasible way that wouldn't put innocent rape victims in jail? | 59 |
ELI5: What's the difference between Club Soda, Seltzer, Tonic Water, Mineral Water, etc. and what's the purpose of the different kinds of bubbly water? | Question struck me as I was grocery shopping today. I think one of them is great for cleaning stains, one helps settle the stomach, and one is good with Gin, but that's all I got. | 169 | Mineral water, like Perrier, is water from a natural spring that has high mineral content & natural carbonation.
Seltzer and club soda are virtually identical. Seltzer is *just* carbonated water, soda has a small amount of minerals added. Most people use them interchangably.
Tonic water is carbonated water with a touch of quinine in it. Quinine used to be use as a treatment for malaria. The tonic water you get these days just has enough to flavor it (and make it glow under a black light). It's often lightly sweetened.
Any clear bubbly water will help you clean out stains. They're all reasonably OK with upset stomachs.
Tonic you mix with gin. Pretty much every other liquor gets mixed with soda/seltzer. | 91 |
ELI5:If only 1% of the water in the world is fresh, why do we use it in our toilets? | 1,470 | Assuming we still want to use water, the alternative would be to use salt water. And the biggest issue is infrastructure.
You would need 2 sets of plumbing. One to handle fresh water for sinks, faucets, hoses, etc, and the other for salt water. This is prohibitively expensive since each house, apartment, pump station, treatment plant, etc. would need to support that. Also, there would need to be more pipes put in place to pump the saltwater to landlocked areas. | 881 |
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[Spiderman:Homecoming] Isn't Cap a Fugitive? | I was just wondering why we see Captain America videos still being shown in gym classes and even in detention if he is an international fugitive after the events of Civil War. | 42 | His fugitive status is top secret. The world doesn't want everyone to panic about the existence of a rogue superpowered team that we have no power to stop. Also, we don't want to deal with the scandal of letting people know about Cap's betrayal. | 64 |
[WH40K] How powerful is the PDF? | How do they differ from the Imperial Navy and Imperial Guard?
Have they ever held out against the enemies of the imperium?
Are there any notable PDF forces? | 25 | They're the primary military force/security on an individual planet. Many Guard regiments recruit from their highest/most experienced ranks.
They can stave off particularly small scale conflicts, like pirate raids or riots, but if an Ork Warband, a Chaos Incursion, or a Tyranid Hive Fleet shows up, they're the first ones to be violently destroyed/eaten/enslaved/sacrificed.
Can't really think of any notable PDFs post-Heresy, but the Prospero Spireguard was a militia/peacekeeping force comprised entirely of normal humans from Prospero, homeworld of the (traitorous) Thousand Sons Legion.
| 30 |
ELI5 why, if our bodies have gone through evolution to fit our environments and make our bodies the best possible, why don't our taste buds think every healthy food we eat is delicious and every unhealthy food is revolting? | 19 | Because for the vast majority of our development, starvation was the main problem. So our food adaptations (higher-calorie foods taste better, our ability to store fat, etc.) are based on preparing for periods of potential starvation later.
edit: fixed typo | 45 |
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[Deadpool movie] *SPOILERS* A question about Angel | So, we are told that Angel is extremely strong. She can restrain Wade without any real effort before he undergoes his 'awakening.' Right before his escape, he head butts her in the nose, and she recoils in pain, holding her nose. Later, we see her going toe-to-toe with Colossus, of all people, and even getting the better of him. He can hit a *lot* harder than Wade can without doing any real damage to her. So, how is it that she feels pain, or suffers damage, when struck by Wade? | 53 | Instinct is a tough thing to overcome. If you spent your whole life being vulnerable to bullets, then you're going to flinch when a gun goes off no matter what mutations you might have. We see this most commonly with immortal beings like vampires who still are known to gasp for air despite not needing to breath. The same situation happened here, Angel recoiled because that's what she was used to for 90% of her life. | 66 |
How does "slingshotting" around a planet or star work? It seems like entering the body's gravity well would require you to expend additional energy to escape it again... | 134 | If you're on a bicycle coasting down a hill, you will accelerate faster and faster. At the bottom, you will actually go fast enough to go up the next hill just by coasting. Now, on a bicycle you won't go as high as you started, but in a perfect world without friction and air resistance, you'll go just as high on the next hill as you started on the first. That's due to the conservation of energy.
In space, there's no friction of wheels on the ground, and no air resistance. So if an object falls towards a planet, it will go faster and faster, and unless it hits the planet or its atmosphere, it will curve around for a bit and then escape the planet in a new direction. There's no need to expend additional energy: the speed you gained during the fall is enough to get you out.
So that's a nice way to change direction without using energy, but you can actually gain speed from it. That's because the planet is moving. Basically if you shoot around a planet coming towards you, by the time you shoot back you will gain up to twice the speed of the planet.
A simple example to illustrate that is like bouncing a rubber ball on the floor. You drop the ball and (in a perfect world) it bounces just as high as you dropped it from. Now imagine that you're bouncing it on a platform that goes up (you are not on the platform, you drop the ball on the platform from above). The ball will bounce on the platform and gain energy from the platform's motion. The result is that it will bounce higher than the point you dropped it from. | 208 |
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ELI5: Why are genitals darker than the rest of their owner? | ... even though they hardly see the sun. Is there a reason genitals receive more pigmentation? | 17 | Your genitals have more melanin, which protects against UV radiation. A long time ago, humans and their ancestors didn't wear clothes, so such sensitive parts did need more protection against the sun. | 23 |
What is daily life like for an atom in the sun? | Of course I don't mean 'life' literally. I'm wondering about the quantum state of e.g. a hydrogen atom/nucleus in the sun. Is it constantly changing? What does it mean to be a hydrogen atom in a plasma, is it always gaining and losing electrons? Or is it like a sea of electrons with a bunch of nuclei floating in it, and those nuclei are the same from moment-to-moment?
Of course some atoms are undergoing fusion at any given moment, but most of them are not. What is life like for the atoms that are not being fused?
(I do not know anything about quantum physics). | 31 | As you already have suspected, the atoms inside of the sun are completely ionised, so we only have nuclei and electrons floating around.
These nuclei are about 75% Hydrogen, so mostly just a proton, and 25% Helium. Of course there are some others but in more or less negligible amounts.
For our sun, only the hydrogen in its core gets fused, the nuclei in the surrounding radiative and convective zones don’t have any nuclear reactions taking place. The „life“ of a nucleus here should be pretty boring.
In the center we have fusion. This can take place in different ways, but in all cases the actual probability for a specific nucleus is really tiny. On average, a proton lives for 9 billion years inside the sun before it undergoes fusion. In the most common reaction two protons fuse to produce hydrogen-2. one proton needs to be converted to a neutron, for which a weak interaction is needed, hence the low probability. Hydrogen-2‘s lifetime in the sun is much shorter because it can just catch another proton to become helium-3. Two 3He finally fuse to a helium-4 and two protons. This step also takes much less time than the initial step. There are other reactions happening, but those only account for less than 20% of the suns energy output.
So Tldr; most of the nuclei and electrons in the sun just float around, lightly bumping into each other, maybe absorbing and re-radiating some photons, but the exciting stuff is pretty rare. | 23 |
eli5: how do beauty marks that show up later in life, “form” ? | like I’m 18 and I’m slowly getting a small darkening beauty mark on my cheek that only showed up about a year ago! So what’s the biology of it? | 26 | Cells on your body are constantly replicating and regenerating, they do this *a lot*.
Sometimes, they get it wrong.
The effect of this is often benign, but sometimes can be serious. This is how cancer starts for example. But a mole, freckle, or beauty mark, is not cancer. Hurray!
Basically, what happened is that the cell whose job it is to maintain your skins pigment, called a Melanocyte develops a fault in the instructions it gets when it tries to do its job. Basically what happens when a mole has formed, is that a cell receives different instructions to the other cells around it, begins spewing out a disproportional amount of melanin pigment in the affected area. The more melanin in the vicinity of the faulty cell, manifests as a brown or black mark.
That's all! It's just a cell that has gone wrong somewhere, and is overproducing melanin, making that very specific area of your skin appear darker than the rest. | 30 |
ELI5: How is it possible to restore species when there's just a few (10+) animals left? | Would not the gene pool be too small?
So I've read about conservation attempts at saving animals that are nearly extinct, and I'm trying to understand how is it not too late if there are so few of them left. Would not their cubs be eventually suffering from from being, well, inbred? | 208 | I don't know where everyone suddenly got the idea that inbreeding is some sort of impossible hurdle to reproduction. Sure, it's not optimal, and will result in offspring that are sometimes mildly less fit than the alternative, but it's still successful reproduction and will rapidly increase the size of the gene pool so that inbreeding is no longer a concern after a few more generations. It is what it is. Sometimes you have no choice. | 336 |
ELI5 why is rocking or swinging so soothing? As in, swinging in a hammock, or sitting in a nursing chair | 828 | Babies have a “calming reflex” when in the womb. The sounds and the motion that the fetus experiences in the womb trigger this reflex. When out of the womb, certain things like rocking, shushing, and pacifiers can trigger this reflex.
As they mature, this reflex goes away and the behavior is somewhat learned, allowing a babies brain to release feel good chemicals (endorphins) when being rocked. This can carry into adulthood.
It’s why hammocks are so nice and riding in a car can put you to sleep easily! | 799 |
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ELI5: If I move a 1 lightyear long "stick", why wouldn't the other end move instantaneously? | 26 | Because there's no such thing as a perfectly rigid material.
The compression wave from you pushing one end would travel through the stick at the speed of sound, so even if you could push enough energy into your end of the stick, there'd be a huge lag before anything happened at the other end. | 42 |
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What would happen if i was going 99.9% the speed of light which would slow down time and I had a phone call with someone not moving?
| 295 | So first of all, there's no such thing as someone 'not moving'. All movement is relative. So it's just as valid to say that you're stationary and they're moving at 99.9%c away from you.
What would happen is that you wouldn't really be able to hold a conversation too well, because the signal between the two of you would take longer and longer to get back. At the moment you passed them you'd be like "hi!" and they'd be like "hey". One second later, there'd be a ~one second before their voice (encoded in light, presumably) reaches your phone. One minute later, there'd be a ~one minute delay. As such, actual conversation would be difficult.
As for what you'd "hear", you'd likely hear their voice just as you normally would, depending upon how the signal from the phone conversation was recorded. In all likelihood, once the signal from their phone reaches yours, it's decoded into sound, which you hear in the usual fashion -- because remember, it's perfectly valid (and physics works identically) if you consider yourself to be stationary and them to be moving away from you. | 228 |
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How is the U.S. allowed to be 14.5 TRILLION dollars in debt? Where is all that money coming from? What's preventing us from defaulting/economic collapse? And why is our currency still considered to be strong? | 26 | The US government offers Bonds, which is basically a peice of paper saying, pay us $xxx and we'll pay you back $xxx+y in z years. Thats where the debt comes from.
Other countries by these bonds, or pensions, or investors or whatever. The bonds are typically very low interest because its seen that governments will always pay back the money they owe people.
The US debt isnt actually that big, as a percentage of GDP its like 60-90% depending on how your measure things, Japan currently has 225% GDP.
What's preventing you from defaulting is the fact that the government can raise taxes, or sell assets or cut services in the future to pay things off.
The strength of the currency is more a factor of the US economy than the debt. | 10 |
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[LOTR] Why do wizards look like men? | From what I understand, wizards aren't mortal men, so why do they look like old men? Are there no dwarf or hobbit looking wizards? | 22 | The five Wizards, or Istari, were sent by the Valar to guide and inspire the people of Middle-Earth to combat Sauron. The short answer is they outwardly appear to be old Men so that they can be most effective in this task.
The longer answer has to do with the reasoning of the Valar and their views of the races of Middle-Earth. Since the Elves are immortal, they were present during the Last Alliance of Elves and Men against Sauron and thus have firsthand experience with him, therefore needing little inspiration to form an opposition. Dwarves are largely self-involved and only interested in gathering and crafting treasures from the Earth, thus being significantly more difficult to rally and inspire. Hobbits, as is frequently the case, are entirely overlooked. That leaves Men. As Gandalf echoed to Elrond, the Valar came to the decision that they must place their faith in Men to resist and defeat Sauron. To that end, they sent their Istari to guide and inspire Men to do this. To engender feelings of respect and trust, the Istari appeared as wizened old Men, rather than strong young warriors.
| 24 |
ELI5: What is the "heel and toe" driving technique and why is it useful? | 93 | It's a technique for downshifting smoothly, and is useful when you need to downshift mid-corner and do not want to upset the balance of the car and risk losing drive-wheel grip from a jerky shift. You see it a lot in "decreasing radius" corners, which means they get sharper as the corner goes on requiring you to slow down.
You use your big toe to press the brake, your left foot to press the clutch, and downshift. Before releasing the clutch, you rotate your foot to tap the throttle (with the other side of your foot/pinky toe) while still braking. This revs the engine a bit, so when the clutch is released, the revs match the road speed and the change is smooth.
You don't actually use your heel most of the time, it's just the term that's been applied, because "big toe and side of foot" doesn't roll off the tongue quite as well. Some cars with a throttle hinged from the bottom (like Nissan Z cars, or an Acura TL) do let you use the heel. Top-hinge throttles like most cars have require the side of your foot or little toe to be used because your heel won't reach. | 46 |
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ELI5: Why does my stomach growl? | What causes the noises it makes when I'm hungry and after I eat? | 19 | Stomach growling is the sound of peristalsis, the process of the muscles in your digestive system doing its thing to move food through you. Normally you can't hear it because the sound is muffled by food in your digestive system. But when you're hungry, the body triggers peristalsis to remind you to eat. You can hear it at this point because there's nothing within your digestive system to muffle the sound. | 19 |
[Big Hero 6] Question about Dr. Callaghan (full spoilers) | I'm utterly confused about Dr. Callaghan's plan and his approach towards executing it. When he was walking around the science expo, was he prepared to steal a piece of tech that could successfully destroy Krei, and was he fully committed to fake his own death at a moment's notice? He didn't know Hiro was going to bring tech that could be a powerful weapon. When he got dressed for that evening event, what was going through his mind? Did he have the building rigged to explode, or did he have some convenient device that could quickly start an inferno so intense that he would stand no chance of being rescued? Did firefighters not find it odd that they couldn't find his body afterwards?
Even more confusing, if Callaghan was so absolutely consumed by his hatred for Krei, why didn't he just wait for him to arrive that night and stab him from behind? Or do the same thing months earlier? He obviously had the means to rig a building for either a fire or an explosion very quickly. Why didn't he just get a tour of Krei's new building and explode it?
You might say that Callaghan wanted to kill Krei in a method that would guarantee his anonymity, but one could easily argue that the plan he chose was far less anonymous than the stab-in-the-back technique. For one, tens of thousands of people in Sanfrantokyo would have recorded the masked Callaghan, and dozens of respectable, trustworthy students and professionals would later come forward and say that the only place they saw that tech before was at an expo in which only two people died: Tadashi Hamada and Robert Callaghan. Even if the police didn't make this connection, however, after Callaghan successfully executed his plan it's not like he could just stroll back onto campus.
He also had an insufficient number of microbots to execute his plan, and had to manufacture more. With this in mind, why didn't he just steal Hiro's idea at his leisure, and then produce the microbots in secret? He would then have an alibi and not have to incur the obvious risks of trusting a brand new technology to save his life in a broiling inferno. If this was a crime of passion, perhaps sparked by Callaghan unexpectedly running into Krei, all it would've taken for Callaghan to enact his plan is to steal the neurotransmitter and a handful of microbots, and he already had access to both of these. If killing Krei using the poetic justice of the Stargate was absolutely essential to his plan, it still doesn't explain why he didn't just ramp up manufacturing in his free time. Also, withdrawing money from your ATM and purchasing manufacturing equipment tends to raise eyebrows when you're supposed to be dead. (And stealing it is perhaps even riskier.)
| 20 | Consider this theory:
**Callaghan's entire plan (burn down expo, steal microbots, manufacture microbots, bring down Krei) was all accidental and ad-hoc.**
Callaghan had (mostly) moved on with his life. He was a successful professor, running a very popular program at a prestigious school. This is not the life of a man bent on revenge. He sees Hiro, young, with lots of spirit and potential, and he has just invented a rather spectacular, world-changing, invention.
Then in walks Krei (obviously uninvited). Krei makes a bee-line for Hiro: he wants those microbots. While Callaghan calmly deflects Krei, the entire exchange had to make him wonder. He knows (or at least believes) Krei will do whatever is necessary to get those microbots. He also might be worried that Hiro will eventually cave to pressure. The microbots are a great invention but they can't fall into the hands of a man like Krei; more people will just die. He has to destroy them.
Be begins trying to destroy them when something goes wrong. A fire starts and he can't contain it. He manages to survive/escape but then realizes that Tadashi died trying to save him. He's distraught. But rather than accept blame for his reckless actions, he blames Krei. This is all Krei's fault. Once again Krei has robbed him of someone whom he cared for. Krei must be stopped. Not just stopped, but publicly exposed. Not just Krei, but his entire enterprise. But how?
As he stands among the rubble of the rubble of the expo he looks down into his clenched fist and opens it:
Inside is a microbot. | 27 |
Fractional Reserve Banking: How does it really really work? (without the cash example). | Hello /r/AskSocialScience
It's been really difficult for me to find an answer to this question, as most articles I find, usually use the 10% cash only example. I have found and read an "alternate" version which seems more plausible for modern times, but I need an expert to prove its validity.
**Here is how I think FRB works:**
Example country: EUROZONE which has only got a 1% Reserve Requirement according to [this Wikipedia article](http://en.wikipedia.org/wiki/Reserve_requirement).
1. Bob goes to the Bank and deposits 100€.
2. The Bank now has Bob's 100€ in its reserves and Bob has an account (bank liability / promise) worth 100€.
Next day.
3. Alice enters the bank and asks for a 9.900€ loan. She doesn't want cash, she wants it in her bank account like most people do nowadays.
4. The bank opens Alice a bank account and gives her the loan. The bank gives her "credit" and types in the numbers in her bank account.
5. Since Alice now has an account, the Bank has a liability towards her of 9.900€, but also an asset worth 9.900€ + interset which is Alice's debt.
Total deposits: 10.000€
Total reserve: 100€
Notice that the bank is still keeping 100€ in its reserves, which accounts for 1% (reserve ratio) of its liabilities.
ERGO: The Bank doesn't need physical cash in its reserves to give out credit.
**And here comes the interesting part:**
The next day both Alice and Bob go to a restaurant and pay with their awesome debit cards.
Bob pays 100€ for his meal, and Alice pays 9.900€ for her meal. Now, what the debit card is actually doing is transfering the liabilities (promises) the bank had with Bob and Alice towards the restaurant owner's bank account.
Notice that we exchange 10.000€ worth of real goods and services for money that did previously not exist and does only so in form of a Bank's promise (credit).
------
Could an expert please point out the flaws and validity of this example?
Thank you! | 30 | Your example is incorrect. The bank can only loan out a 99% of the deposit Bob made into the bank. So Alice can only be offered a 99€ loan if the bank deposits worth 100€. However, when Alice deposits her loan into another checking account, the bank that oversees that checking account can now loan out 98.01€, and the next bank can then loan out 99% of that, or 97.0299€. If banks continue lending ad infinitum, the deposits will eventually increase by 10,00€ (10.00€) including the initial 100€ deposit.
If the bank could lend out 9,900€ on the deposit of 100€, the bank in which Alice deposited the 9,900€ could then make a loan for 980100€. The next bank could then loan out 97,029,900€, and so on. This obviously doesn't happen, but it seems to be a common misconception about fractional reserve banking. | 20 |
Does a combustion reaction always need to have an organic compound and oxygen gas as the reactants and water and Carbon dioxide as the product? | What if there's no organic compound present in the reaction? Is that considered already as not a combustion reaction? | 1,073 | To an extent it depends on what you mean by "combustion". If you take a "man on the street" interpretation of an intense reaction with visible "flames", there are plenty of examples that fit the description. An obvious set of examples are the way certain metals will burn in air, for example magnesium. The question is a bit difficult to answer scientifically, though, because "combustion" is not a terribly well defined term, and similar reactions can occur in different chemicals that in one case resemble combustion and in another case do not, but they are chemically similar. | 401 |
How many of the stars we see probably don't exist anymore? | Light only travels so fast, and some of these stars/galaxies are millions or billions of lightyears away. Is it possible to estimate how many of these have died or ceased to exist, even if we just don't know it yet? | 667 | The only stars you can see with your naked eye are definitely in our galaxy, and our galaxy is only about 100,000 light years across. Stars lives are on the scale of millions to billions of years. So any star you can see with your naked eye has a pretty good chance of still being "alive". | 434 |
ELI5: How do bongs work? | I know how to use them, please don't explain how to use them. I just want to understand what's happening when you're using a bong. | 15 | The smoke has some of the tars filtered out and is cooled somewhat when it's drawn through the water. That's the whole point of using a bong or other waterpipe. You apply suction (negative pressure) and it draws the smoke through the water. | 15 |
Does convergent evolution lead to similar genotypes in addition to the similarities in phenotype? | 19 | It's possible, but very unlikely. It would be like if two people on opposite sides of the world both wanted to write a really popular novel and the books they wrote had not only the same themes but the same plot, characters, writing style, etc. A different analogy: if you and a partner were to both roll dice until all of your rolls add up to 100, would your series of rolls look anything alike, even if you reached the same result? When we're thinking of something like wings of insects, birds, and bats, it just doesn't make sense that the millions of base pairs coding for development of the wing would be anything alike, even if they form a similar structure.
Scientists (geneticists) use this assumption to make phylogenies. They more or less disregard the function of the genes and look only at the form (what letter is where, how many letters and chromosomes there are) to establish relatedness of species. This is the same thing we do (though less precisely) when we disregard the differing functions of a whale fin, a human arm, and a bat wing to look at the similar skeletal and muscular form to infer recent common ancestry.
Basically, the genes for a bird's wing are going to be more similar to those for a bat's wing than to those for a butterfly's wing, but that is because they are more closely related, not because they have a more similar function. By that logic, a hummingbird would have genes more similar to a bee (based on flight pattern) than a hawk. | 13 |
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why doesn't an atomic bomb cause a chain reaction and start spitting and exploding other atoms around it? | 52 | The same reason, more or less, that your fire doesn't burn the fireplace: the fireplace isn't made of fuel.
Only a few types of heavy atom are subject to neutron-induced fission. When neutrons hit (say) concrete, the concrete doesn't emit yet more neutrons.
Thermonuclear detonations (fusion bombs) are even more analogous to a very high temperature fire: they work by heating light elements very hot, and those elements fuse and release more heat that allows the reaction to continue. Most light elements can yield energy through fusion, so in principle a large enough hydrogen bomb could fuse (say) all the nitrogen in the air. But it turns out to be very hard to keep the heat from fusion concentrated enough to enable further fusion, just like a firecracker going off in a forest doesn't necessarily set all the trees on fire. Except worse, because fusion requires very high temperatures to achieve and it takes something the size of a star to keep the "fire" going. | 73 |
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Are we, by paying our taxes, complicit in imprisonment, torture, rape and murder? | Our government's agents regularly commit heinous acts of imprisonment, torture, rape and murder. By paying our taxes we fund such activity. Does that render us culpable? | 181 | Taxation, by definition, is compulsory - we don't get a choice whether or not we pay taxes (or, more accurately, our choice is between paying, or suffering a harsh penalty). This is the case regardless of the moral status of a particular government. Typically, being forced to do something is not seen as being ethically equivalent to doing something purely by choice, regardless of your ethical model of choice. | 102 |
Is it too late for me to leave phd program? | I'm a PhD student that has realized (over the course of the last 2 years) that I do not want a career in research. I don't even want to do industry research and I certainly don't want to do academic research.
My issue is that I'm ABD. I passed my Qualifying Exam last semester. But...I don't have a proposal in sight. I've completed 2 research projects, and I'm working on something now that I *think* will lead to a proposal to bring them all together. My advisor never wants to talk about a proposal. She just keeps telling me not to worry about a proposal, but how can I not? I'm in the middle of my 4th year and I can only stay 1.5 more years after this. I need to propose within the year to have a reasonable chance of graduating within 1.5 years. I can't stick around indefinitely like some phd students seem to do.
If I stay, I *might* be able to graduate within 1.5 years, but nothing is guaranteed in research, and I haven't even started writing a proposal. Am I in too deep? Am I pot committed at this point? I dread meeting my with advisor, I constantly worry that I'm not working on something that will lead to a proposal, and I just feel all-around unhappy. The only things keeping me going are 1) I'm ABD with 2/3 of the work "done" and 2) I'd be interested in lecturing positions in the future and having a PhD would help with that. | 17 | I research doctoral attrition. It's never too late, I've known people who finished their proposal and then never completed and left their programs.
I think you need to sit down with your advisor and have a blunt conversation about where you're at and what you're considering, as well as your timeline concerns. That might help you to determine if you want to continue or not. | 22 |
Why don't we see eclipses of external stars? | The question is pretty much the title.
Why don't we see a constantly changing night sky with stars popping in and out of our view through let's say star bound planets crossing our path of vision?
Shouldn't there be a significant amount of stellar eclipses happening all the time, visible to the naked eye?
I'm looking forward to being educated and thanks in advance, all input is appreciated :) | 50 | We do, that's how exoplanets are detected. But they're not visible to the naked eye, the drops in brightness are every few days (more more) and are typically less than a percent of the star's total brightness. The human eye can't detect that, it can't even see most stars. | 74 |
ELI5:Do horses know they're racing? | I've been told that when they win they're spoiled with apples and treats and stuff, but how do you teach competition to an animal? how do you make it understand that it is supposed to go faster than the one in front of it? how do we know they're not all just running together and wondering why the little guy on top of them is hitting them so much? | 20 | A racehorse usually doesn't need to be taught competition because they're born with it. Over hundreds of years people bred horses to be very fast, aggressive, and competitive.
Does this mean they understand when they've won a race? Not really. But they definitely want to show the other horses that they're the toughest and fastest. In fact, sometimes the jockey has to actually slow his horse down, because otherwise the horse will run too fast too early, and get exhausted and lose the race. | 18 |
CMV: Victims and suspects deserve the same amount of anonymity in news coverage stories. | If a victim or a minor does not wish to have their name and age disclosed on media coverage, whether it be through a news article online or in print, or a news story through television, then the suspects or criminals being arrested in breaking news stories should also have the same choice of anonymity. For example, there is a recent story about a woman in a vegetative state who got pregnant by a nurse at a healthcare facility. The nurse was arrested for sexual assault and abuse of a vulnerable adult with his name and age given to the public through numerous news outlets while the woman's name was not disclosed, but her age was. The man should not have his name and age disclosed like that if he does not want it to be. Change my view. | 25 | While it has its down sides, especially in sensational cases, the fact that the names of the accused are public is a really important aspect of U.S. Democracy and freedom.
When you hear about somebody in another country being "disappeared", then you're hearing about what happens when the names of the accused aren't public. The government can simply quietly arrest someone, try them, and convict them out of the public eye, without the obligation to inform anyone of the reasons why, or give friends and family a chance to step up and help the accused out.
A system of justice needs to be as transparent as possible to prevent abuse. And a public accounting of ongoing accusations and trials is a critical part of that transparency. | 14 |
To all Computer Engineering/Science students & graduates, what sorts of projects did you do during college and what do you recommend for the students currently in CS program? | I am not sure what field to enter after completing my undergraduates. I want to get a taste of all the options before considering something to do all my life.
I am a Computer Engineering student in my 5th semester. I wanna know what sorts of projects or things are my fellow CS students learning and doing in their university? Even the graduates can share their experiences and projects. Mentioning languages, tools and the benefits from those projects would be highly appreciated.
Any tips regarding how to figure out the topic for me would be great as well.
I am sure it is just not me confused with the mushrooming fields around CS to choose a career from. So, any help/suggestions from fellow students, graduates or even professors would be appreciated by a whole lot of us.
Thanking you all in advance! | 20 | There are a number of things you can try to do, I'll just list some that come to mind:
Build an application that lets users upload an image, and it says whether that image contains a flower or a dog. Architecture this app as a web app with React/Vue/Angular on the frontend and Python/C# on the backend. Use a neural network to do the image classification to try your hand at deep learning. Make a CI/CD pipeline which runs tests and publishes your app as a Docker image to a Docker registry. Deploy your app to a cloud platform like AWS/Google Cloud/Azure using your Docker image. Bonus points if you try your hand at Kubernetes.
If you do something like that, you'll get a cross-section view of a bunch of software fields: frontend, backend, ML, CI/CD, cloud. You can decide for yourself which parts you enjoyed the most, and enhance your project in those areas.
Enjoy ML? Improve the accuracy of the model or give the users an option to add new classes of images (like boats).
Enjoy backend/frontend? Add more features like batch asynchronous processing, multithreading etc.
You can make a mobile client app for this.
If you enjoy the cloud aspect, you can configure GitOps, or improve your deployment by adding rolling deployments or redundancy. Learn about Kubernetes and Helm.
That's just an idea, you can take it anywhere you want. | 10 |
[Star Wars] Does R2-D2 recognize the significance of Anakin's fall to the Dark Side? Does he have moral agency and so fights with the rebellion, or is he merely "swept" into the fray? | 478 | I've always loved (and agreed with) the fan theory that R2D2 is one of the main spy agents of the Rebellion, working as the real operative while C-3PO is loud and obnoxious, and thus draws all of the attention. If you think about it, R2 has been at the heart of the Rebellion since the very beginning, and hasn't had a memory wipe since. Droids in Star Wars become more individualized the longer they go without a memory wipe, and he's way, way overdue. He can basically serve as the main hacker (slicer, in Star Wars parlance) that the Rebellion has access to without anybody thinking of him as anything more than an astromech droid. | 302 |
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Eli5 Why does saliva taste like blood when you exhaust yourself? | Why does your saliva start to taste like blood if you ride your bike up a hill or run fast for a while?
Edit: Thanks for the Awards and the nice Comments.
Also blew up bigger than I thought! | 20,802 | When you complete a quick, strenuous exercise, some excess hemoglobin is released from your blood cells into the lungs, which is then moved to your mouth during an exhale. Since hemoglobin is also made up of iron, that is what your receptors detect- hence the blood taste. | 16,852 |
ELI5: What are the results of the Indian Elections, and what does it mean? | 253 | The Bharitya Janta Party (BJP; rough meaning Indian People's Party) recorded a solid landslide, gaining a clear majority in their own right in the Lok Sabha (People's house, analogous to the House of Reps), and with their coalition partners control a solid majority of the 543 member lower house. The Congress party that previously held government has been reduced to a fairly tiny 50 or so seats, and their leadership is in somewhat disarray. Most of the remaining seats are taken up by minor regional and small issue parties.
The BJP is the conservative party, right of Congress. In American terms, it is a thumping win for Republicans. Note however the Indian political realities puts the BJP somewhere around the Democrats, while the previous government could have been described as borderline socialist.
India hasn't seen a party with a clear majority for 30 years, so while the BJP are so far indicating they'll retain their coalition partners (mainly because they'll need them in the upper house, which isn't yet clear), they could push through their agenda without the compromises and delays that have dragged down politics in recent history.
PM designate Modi specifically: as a former chief minister (governor) for Gujarat state, Modi achieved significant economic growth, attracting business from overseas and other parts of the country to an area that hadn't had such development for years. As a result, he has been seen to bring a pragmatic and business focused reform agenda. India's middle class has been complaining of rising inflation with (relatively) low growth, so the hope is that he'll control the former while encouraging the latter. Modi is the _first_ prime minister of India born after Independence, though at 63 he is no spring chicken.
Modi has his critics. He is seen as being passive in the face of sectarian violence against Muslims in his state 12 years ago, and he hasn't quite shaken it. The BJP's association with the religious movements (like any Conservative party) is troubling to minorities, particularly Muslims, but with 150 million Muslims in India and two neighbouring Muslim countries in Pakistan and Bangladesh, the BJP would be suicidal to actually do anything that would be anti-Muslim. Other minorities are considered small enough or inconsequential enough as to not be worth ruffling (no perceived threat from Sikhs, Jains or Buddhists.)
Any more and you really start delving into history. | 77 |
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[General] Are there non-psychically capable people who have such natural mental strength and will that they can resist a psychic invasion of their mind? | Generally, psychic powers are portrayed with people falling into three general categories: (1) psychically capable; (2) neutrally capable/non-psychic; (3) actively anti-psychic powers.
In several universes there are examples of non-psychic people being taught techniques to resist someone invading their minds.
However, what I’m wondering about is if there examples of non-psychic people who just have such strong mental will that they could resist a psychic? For instance, when we see Picard being tortured by the Cardassians we see his mental will in resisting them. I’m thinking about a psychic trying to read Picard and his internal voice being able to resist them. Does anything like that exist? | 17 | Storm in X-Men is considered extremely resistant to mental manipulation.
Superman has also had training to resist psychic influence, and Joker simply can't have his mind read because it's too much of a chaotic and unstable mess for anyone to make sense of. | 22 |
ELI5: Why when you zone out(daydream), do your eyes go wide and you don't blink? | Why is it that happens? Or does it just happen to me and the people I see zoning out? | 41 | because your frontal cortex's neurons aren't firing at the same rate of the rods in your eyes leaving a blank image that repeats tricking your mind to think that it's seeing a still image when in reality it's seeing in real time with parts of the retina blurring it out and the blurring happens do to your eye widening. | 18 |
AskScience AMA Series: We are Dr. Karen Cranston and Dr. Stephen Smith, computational and evolutionary biologists at Duke and U Michigan and other members of the Open Tree of Life team, here to answer questions about the Tree of Life, AMA! | Hi reddit!
We have just released a draft of the tree of life (http://www.pnas.org/content/early/2015/09/16/1423041112 ) that includes 2.3 million named and extant species. This is the first attempt to automatically combine published evolutionary trees (phylogenies) into a comprehensive tree of life. This publication is only the beginning, and we will update the tree of life based on feedback and contributions of newly-published data. Our database of published trees and the underlying taxonomy provide additional important resources for the broader community, allowing people to do their own analyses, including but not limited to building their own trees.
Answering questions are:
Dr. Karen Cranston, Duke University
Dr. Cody Hinchliff, University of Michigan
Dr. Mark Holder, University of Kansas
Dr. Stephen Smith, University of Michigan
Dr. Joseph Brown, University of Michigan
Dr. Jonathan Rees, Duke University
We'll be back at 1 pm ET (10 am PT, 5 pm UTC) to answer your questions, Ask Us Anything about the Tree of Life!
**EDIT: We are finishing up for now. Thanks to everyone for all the great questions!! If you want to stay up to date as the project continues check out our [blog](http://blog.opentreeoflife.org) and [twitter](https://twitter.com/opentreeoflife).** | 2,022 | What did you discover at the root of the tree i.e. is there a point of origin?
How long did it take you to compile this?
Can this data be used to predict or see evolutionary trends?
How is the data stored and how big is it? | 71 |
ELI5: When burning a CD, does a 4x vs a 1x write speed change the quality of the end product? Is there anything different about a 4x vs any other speed other than, speed? | 44 | I always thought this harkened back to the old days of CD burning, where buffer underruns occurred frequently. A buffer was created for the data being burned, and if the buffer emptied before the burning process is complete, it would fail.
Burning at a slower speed (1x) meant you didn't empty the buffer and cause problems. However if your PC could handle it, you could attempt to burn at faster speeds (4x). | 24 |
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What determines if it is called a road, street, drive, lane, boulevard, highway, avenue, parkway, etc.? | Is there actually a nomenclature system or is it all arbitrary? | 195 | In Gainesville Florida it is very precise. The basic lay out is a grid of squares that are all numbered streets (north-south) and avenues (east-west)
Between two numbered streets, say between 20^th st and 21^st st are IN THIS ORDER 21^st terr, 21^st drive, and 21^st way. All odd number addresses are on the west side of the pavement.
Between two number avenues, say 16^th Ave and 17^th Ave are IN THIS ORDER 16^th Place, 16^th Road, and 16^th Lane. All odd number addresses are on the south side of the pavement.
Boulevards cut across the diagonally
University Ave and Main Street are like the x and y axis that cross right downtown and all the numbering counts out from there.
An address might be 2025 NW 16^th Lane. (notice it is odd)
From that address. the 20**25** the last two digits are used to number the houses on the block, the rest of the digits tell you that you between 20^th St and 21^st St, the NW tells you you are North of University Ave, and West of Main St and 16^th Lane means you are between 16^th Ave and 17^th Ave, and since it is a Lane it comes after the Place and the Road. Now since it was an odd number and the address is on a lane your house is on the south side of 16^th Ln.
So it may have arbitrary origins, but they are assigned in a very orderly manner in Gainesville, FL.
**NOTE** Not all St, terr, dr, ways, Av, pl, rd, ln exist. but when they do exist, they exist in that order | 67 |
ELI5: after pulling you over, why do cops sometimes stand near your door handle, facing forward where you can't make eye contact, rather than standing at you mirror, facing you? | Sometimes an officer will stand closer to where your car door opens/where the handle is and face forward, making it impossible to make eye contact or even see their face.
What's the reason for this? Are the looking for something in particular? | 27 | They want to be able to see your hands and glovebox, places you might have a weapon. You also can't easily exit the car if they stand by the handle. They don't need to see your face until they know they are safe. | 17 |
[General Sci-Fi/Fantasy] If a dragon lived long enough to make it to a futuristic world where gold had lost most of its value and people traded in 'credits', would he try and hoard the credits or keep with the gold? | Or would he do something else? | 229 | I believe Shadowrun did exactly this - the antagonist of one of the games is a dragon who is a CEO of a major corporation with a lot of influence and money.
Said dragon can also shape shift to look like a human.
So, something along those lines. Power and greed are still there. | 242 |
[LOTR] Why does Saruman have a tower? What was it built for? | The tower of Isengard is clearly way too large for one man to use, perhaps even too large to be practical at all. Why was it built and why does Saruman choose to live there? | 32 | Orthanc was orinally built by Númenóreans or more so their coastal breathen Dúnedain. It was both and outpost and a communication array. The stones of Orthanc or Palantír were gifts from the elves that were used to view far and wide, it can be assumed the tower itself helped in this function much like the Seat of Seeing on Amon Hen.
As to why he lived there it was a gift from Gondor after their power had started to wane. It was left abandoned and Saruman was interested in both the stones and he used them to often to view Mordor. | 39 |
[ASIP] How does the gang do in a zombie apocalypse? What's the best and worst possible scenario? | 16 | They would last a pretty long time. Frank would have stocked up on guns and water filters. Charlie is an expert at foraging and scavenging. Mac is a master of hand-to-hand combat and can conduct ocular pat-downs to assess if a person is infected. Dennis is the Face. He conducts trade and deals with other survivor groups. Dee is a drunk whore and will sell her body for bird seed.
They would wait out the first week or so in the bunker, then eventually get bored and leave. They still wouldn't go outside, just sit around Paddy's and yell at each other. By the time they need to venture outside, the worst part of the collapse will be over.
Worst case scenario is that Frank gets infected first while partying with Pondy under the bridge. He turns in the night and bites Charlie while he is unconcious from cat food and inhalants. Dee, Mac, and Dennis and unprepared and Mac and Dennis quickly decide to sell Dee for survival supplies. After a week of surviving together in close proximity, they both slowly start to go crazy and eventually let down their guard, allowing zombies to get in the bar and corner them. | 34 |
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If HFCS is fructose and glucose, and raw honey is also mostly fructose and glucose, what makes HFCS *that* bad? | Honey is often hailed as having medicinal benefits (or at least being not as bad as table sugar), whereas HFCS is in multiple nutritional black lists (figuratively) and is feared by many for its harmful effects being much worse than straight up table sugar.
Often the explanation is that HFCS has higher fructose which is the bad thing about it, when honey usually have similar if not even higher fructose content compared to glucose. So what gives?
I know that honey has enzymes, minerals and vitamins making it somewhat beneficial, but this doesn’t change how the body absorbs and metabolizes fructose whether in HFCS or honey. So what’s the deal here?
Is honey just as bad as HFCS or is HFCS not as bad as it is made out to be? Or am I missing something? | 2,450 | The problem is not that HFCS is itself bad for you, the problem is that it is cheap and easy to put in foods so manufactures tended to put it in \*everything\*. It's gotten better over the past few years, but for a while every processed food had HFCS in it -- potato chips, canned fruit, sausage, bread products, and every single beverage.
Think of it as pouring honey over everything you eat and in the water you drink. That would be pretty unhealthy for you. | 3,868 |
ELI5: Why can we not change the colour of steam? | Why is steam always white, even when the liquid isn’t? Maybe it is possible to change, but I couldn’t find anything. I tried Googling but every search result was about Steam gaming. | 29 | The white you see is not steam but clouds of tiny droplets which have quickly condensed back to liquid water. The colour comes not from the liquid itself but from the thousands of tiny surfaces of the droplets that scatter light around randomly. Steam itself is largely transparent though it will often have a shimmering mirage-like appearance when we look through it due to temperature variations. | 53 |
ELI5: Why are there no giant bacteria? | How big can a bacteria get?
Why are there no real life "[Gelatinous blobs](https://en.wikipedia.org/wiki/Gelatinous_cube)"
Edit: thanks everyone for your answers, love the icream analogy! | 83 | Ok, so do we all like ice cream?
Today you get to have any amount of your favorite flavor, and then cover it with as much topping as you want. Let's say you love chocolate sprinkles.
Your eyes shine and you scoop the biggest ice cream ball the world has ever seen. It barely sits in the cone. And now you cover it nicely all around with 2 spoonfuls of sprinkles. Nice!
Then it's your cousin's turn. To a bowl she adds the exact same amount of ice cream you did, but instead of a huge ball, she splits it in 6 smaller scoops (lame!)
But you don't expect what she does next: taking the same 2 spoonfuls of sprinkles, they just cover 2 of her scoops! While taking 4 more spoons of the chocolatey deliciousness, she winks at you and you finally realize – you've played yourself. You might have the biggest ball, but she has the same amount of ice cream and her topping game beats yours. Good luck enjoying that giant dull scoop after the first bits...
Now to bacteria, they're like ice cream scoops: they need a big surface to get their good stuff (food, "air"). To keep the balance, they stay nice and small so they don't go "dull" :) | 174 |
[Watchmen] why does Rorschachs mask move like it does? | I saw a video on the news of Rorschach and his masked looked like it was moving is there any reason behind this does anyone know? | 42 | The mask has an outside layer, which is transparent, and an inside layer. Between the layers are two fluids, one black, one white, and about as thick as oil. The fluids are of a type that they never mix, and body heat/movement keeps them in motion. The design of the mask keeps the shapes made symmetrical down the center (I have no idea how that part works) | 50 |
ELI5: Why are artists now able to create "photo realistic" paintings and pencil drawing that totally blow classic painters, like Rembrandt and Da Vinci, out of the water in terms of detail and realism? | Don't get me wrong, I find many of the classic works amazingly beautiful, I'm just trying to figure out why the old masters were not able to create art with the same level of detail and realism as what can be found in this album: http://imgur.com/a/3Bqjx#0 | 3,655 | Contemporary artists have a lot of advantages over classical artists. They have a better variety of tools and media, like airbrush, and higher quality paint. They have an additional 500 years of art history to work from, during which other artists have done a lot of work and developed a lot of new techniques. Also, they have photos to work from, and aren't constrained to live subjects. So, they can spend a lot of time looking at that reflection up close and seeing exactly what the shapes and colors are. | 4,339 |
CMV: The US government should produce and print textbooks and provide them for free to the public/schools/students. | This is a policy idea I've been kicking around in my head a bit. Essentially, the government would finance (maybe through a prize based system) the writing of public domain textbooks for most subjects/grade levels in the US, and provide copies of them free of charge to any American who asked, and to schools who asked.
The reasons for this are:
1. Schools are already almost entirely a government-run project, and this would be a much more efficient way of procuring textbooks than the current system of paying overpriced private contractors on a per-book basis. So I think overall it would take less government money than the current scheme.
2. It would substantially aid people in college and homeschool students who currently have to pay for their own books.
3. It would produce a large volume of public domain works people could spin off from to produce their own versions if they wanted without having to worry about copyright.
_____
> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | 1,170 | It would get way too political.
The central government selecting the *exact content* of what the entire country’s next generation will learn? Every politician, especially every president, will want a hand in deciding which textbook to go with and what the content, phrasing, etc. should be. It will become less about learning and more about pushing an agenda and trying to indoctrinate youth.
Not to mention the cost of such a program. Many Textbooks today will remain in the classrooms for at least a decade, and the constant need to update isn’t all that prevalent. But because of the wide audience and the political aspect of it, each new president (at least) would most likely input a new textbook. Then some teachers and school districts would rebel against the new books (Trump text) in favor of the old books (Obama text), because why not? They still have copies of the old books anyway.
So then schools will show their political stripes by which iteration of the textbooks they use; and the polarization of American media and government will worsen as a result.
It’ll become a big political mess over what should go in the textbooks and which textbooks to use, so as nice as it would be to have this funding, it’s not really feasible.
However, you could have a government-backed “model” textbook and public-provided funding for *any* textbook that cost the same as the model one. That might be a way of saving your idea without the monopolization. | 628 |
[StarWars] Did Anakin get stronger after the fight with Obi-Wan on Mustafar? | I've been told Anakin's wounds (I.E. losing two legs and an arm) in his fight with Obi-Wan on mustafar weakened his ability to use the force.
If so, was Anakin at the peak of his power when he was defeated by Obi-Wan? or did Anakin become stronger during his time as Darth Vader? was Anakin in a weakened state when he fought Obi-Wan? | 59 | Anakin's maximum Force potential was lowered by his injuries on Mustafar. Had he not suffered his dismemberment and horrific burns, then he had the potential to eventually be approximately twice as powerful as Sidious. As it was, though, after Mustafar his maximum ceiling was approximately three quarters of Sidious's power.
Keyword here is potential. At the time of his duel on Mustafar, Anakin wasn't at his maximum power yet. So after he was put in the suit, he continued to develop his Force abilities, and actually became stronger in the subsequent years. But he would never be strong enough to challenge Sidious directly.
As for his combat skills, being put in the suit made Vader less mobile, which meant his saber skills had to be adjusted. He adapted a more power-oriented style, compared to the fast and mobile Djem So style he practiced pre-Mustafar. His new style was still devastatingly effective in combat, though, as evidenced by the fact that he defeated so many Jedi in the Purge. | 73 |
elI5 Why are sleeping bags made out of such loud materials? | 73 | Sleeping bags are usually synthetic material (nylon) filled with more synthetic insulation or goose down. The priority for most sleeping bags is to minimize their weight and bulk as much as possible while still achieving the needed warmth. Thin nylon does this better than almost any material, but has the downside of making that annoying swishing noise. There are sleeping bags out there that have a liner made from linen or flannel like material that’s much softer and quieter, but those bags tend to be a lot bulkier and more suited to RV camping rather than backpacking. | 135 |
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Does gradual cold exposure(cold showers, ice baths,etc.) Increase your blood circulation over time? | It seems to spike your metabolic rate, at least that is what I heard. Anyone know if it helps with blood circulation as well? | 149 | It most certainly does. The reason why your metabolic rate increases, is because your body is trying to keep as warm as possible, (through pilo erections (goosebumps) and minute muscle contractions. This all requires ATP, and produces heat. So your metabolic rate tends to increase. When you're exposed to the cold, your body loses heat to the environment, this heat is lost from the blood. E.g, blood that leaves the heart at 37 degrees, may arrive back at the heart at 36.8 degrees for example. Therefore it follows that circulation of blood may increase, to make up for this loss of heat and to keep on providing constant heat to your body parts. All of these activites require alot of energy, and the body has to withdraw resources from other sectors "hypothetically". This is why you can get sick when you are exposed to the cold. Your body uses all of it's energy to maintain homeostasis leaving little else for immune response. However, this increase in circulation can only be sustained for a short period of time, If this cold temperature is maintained for long enough, the bodies primary energy sources are depleted and it then one becomes hypothermic, and a couple of fingers fall off, and that sort of thing. | 34 |
ELI5: How are billionaires able to pay such a low tax rate? | I know they write off stocks somehow, and some use something called the "variable prepaid forward contract" however this stuff makes my head spin. Can anyone break down how this is possible? | 40 | Billionaires make most of their money off various sorts of investment income (which affects a very small percentage of the population) rather than payroll taxes (which affect most people).
Given the total tax liability of a typical billionaire, it's usually very cost-effective to do some combination of restructuring their income to avoid taxes (relatively easy, since they're probably a CEO or major shareholder of a company that employs lots of high-level accountants), or lobby the relevant national government to add a few tax loopholes that benefit billionaires with their specific income structure.
In other words, you don't need to understand the details of the "variable prepaid forward contract;" the important thing to understand is that once you make a sufficiently insane amount of money, it's much cheaper to game the tax system than to pay your fair share. | 25 |
[Futurama] How was the Lunar Lander lost centuries ago? | Leela claims it as lost but with the technology they have, they explored there universe in no time at all. Could they not do a circle around the moon and find it ? | 33 | The same way that Bender is composed of:
* 40% Zinc
* 40% Titanium
* 30% Iron
* 40% Dolomite
* 40% Lead
* 40% Luck/horseshoes
* 40% Chromium
* 60% Storage space
* 40% Scrap metal
* 40% Wire
* 40% Empty | 31 |
If captchas are supposed to differentiate between man and machine, how does the server confirm I wrote the correct letters? | Aren't those pictures generated randomly? If a sequence is first created, and the picture thereafter, couldn't a bot just re-do the steps to get from the picture to the text sequence?
Edit: Thanks guys! So you it's not really hard to distort the picture in a way that is practically impossible for a bot to re-do. Also, the crowdsourcing thing looks really interesting. I'll look further into it! | 36 | Some processes are easy to do in one direction but hard to undo. It's easy to take a series of letters or numbers and to apply a series of random effects to it, but it's hard to figure out exactly what those effects were. Even if you knew that one of the effects was "draw a black line from one random point to another" it could be difficult to work out which pixels were part of that random black line and which ones were part of the original letters. | 41 |
Why do Mars rovers work so much longer after their mission is over? | I saw Opportunity is going on 4000+ days, for a 90 day mission, but even Curiosity, with a much longer mission, is now hundreds of days past it's mission end date. What were their original missions, and what are they doing now? Is there a list of mission objectives, and then an extra long list of potential extra things they want to do if possible?
Thanks | 1,925 | With Spirit and Opportunity, there is a specific reason. It was expected that the solar panels would quickly become coated in Martian dust, and soon the rovers would not receive enough power to function. However, the Martian wind turned out to be quite effective at cleaning the solar panels, so while they look fairly dirty they never get completely covered. As solar-powered rovers, they can basically run forever until they start breaking. This won't happen for Curiosity because it's nuclear powered.
But in general another part is probably just the mission planning, where they set a fairly low standard for "success" - acknowledging that lots of things can go wrong - and so they can declare the basic mission a success fairly quickly. | 1,339 |
ELI5: If space is a vacuum, how come it's so cold? | Wouldn't there have to be something there to be cold? What's making it cold? | 104 | Unfortunately, space isn't just space. How "hot" or "cold" it is depends on where you are. It also doesn't help that heat "moves" differently in space than it does on earth due to the vacuum.
If you have a thermometer in your house and take it outside, it will warm up or cool down until it reaches the same temperature as everything around it, with "everything" mainly being the atmosphere or whatever rock/table/bit of ground you left it lying on. By coming in contact the atmosphere and the ground, the thermometer can easily exchange heat with the environment and will soon give you an accurate reading of the temperature.
Now let us imagine you're on the International Space Station and you do the same thing. You take your thermometer out of the ISS and leave it floating a little bit outside the airlock. Let's say you also did this "at night", i.e. when the ISS passes through earth's shadow so that the sun doesn't interfere with your experiment. The thermometer's temperature will barely change. This doesn't mean that the space is the same temperature as the inside of the ISS, it's just that your thermometer can't exchange heat the way it would on earth since it's in a vacuum. It will cool VERY SLOWLY by emitting so-called black body radiation (this is exactly the same as the light that metal gives off when it glows red hot, except that your thermometer is only at room temperature, so it only glows in the infra-red).
Now let's say you wait a little longer. The orbit will carry the thermometer out of earth's shadow into full sunlight. Now, the thermometer is giving off a little bit of IR light (which cools it down slowly very slowly) and absorbs large amounts of light from the sun (which heats it up rapidly). This means that your thermometer floating in space will get HOTTER! And for quite a while, it will continue to get hotter and hotter. However, as it gets hotter, it will emit more and more black body radiation until the radiation it loses is equal to what it gains from the sun. At this point, it will be showing the "correct" temperature, which is quite hot for the ISS. After all, when you're in orbit around earth, you receive more light per square meter than if you were sitting in the Sahara desert at mid day.
Finally, let's imagine that you did the same thing from a space ship that was floating in deep space (i.e. well outside of our galaxy). Now the thermometer will lose heat through black body radiation as it did before, but there is no sun to heat it up. The only light it can absorb is the so-called "cosmic microwave background", which is the left-over light from the big bang. But otherwise, the situation is the same. The thermometer will continue to lose temperature (and hence will emit less and less black-body radiation) until it is giving off as much as it is receiving from the CMB. This happens at about -270C, which is very cold indeed. This is why people say that space is cold, but it's really only true for deep space. | 112 |
Eli5: Why do some exercises (eg. wall sits) hurt intensely in the moment but cause minimal soreness, whereas others (eg. deadlifts) feel effortless in the moment then hurt terribly the days after? | 17 | I kinda see where you're going with this. But, if deadlifts feel effortless, you may need to increase the weight.
To simplify, there is central, and peripheral muscle fatigue. Central refers to the motor neurons of the nervous system. This tells the muscles to contract. The more force you need, the higher the frequency.
For wall sits, it's a much lower amount of force. But, since you're holding it for longer, the lactic acid produced by muscles when contracting has longer to build up, causing that initial soreness.
The delayed onset muscle soreness (DOMS) you're referring to is still not totally understood, but believed to be a result of the damage we do to our muscles when we use them in ways they aren't used to yet. But, some people still get DOMS even after months or years of regular training, but it's usually much easier to manage. | 10 |
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