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ELI5: How countries like Costa Rica can just abolish their military and manage to live without an army for so long time?? | It was abolished in 1949!! | 286 | Who lives right next door to Costa Rica? - The USA.
The same USA that has made it absolutely clear that nobody... NOBODY picks a fight with the people in our backyard (except us). The same USA that spends more money on military than the next 10 countries on the list combined.
Costa Rica doesn't need an army... they have the US military. | 252 |
Are domesticated animals like cats & dogs conscious about gaining weight? Do these animals "feel the need" to lose weight like humans do if they ever become too slow? | 15 | The answer is probably not entirely scientific, but why would they? Animals don't understand that if you eat too much, you gain weight. They don't make plans that take months to work out. They don't conceptualize looking fit for a partner. Animals do not become fat in the wild, so there is also no instinctive response to becoming fat. | 14 |
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[Dragon Ball Z] Can the Dragon Balls be destroyed? Is there something that prevents them from being destroyed? | 17 | While no one has directly tried to destroy the Balls themselves, the fact that Shenron was killed by King Piccolo, and that Vegeta killed Piccolo (which killed the Dragonballs) suggests that the Dragonballs are far from being invulnerable. | 20 |
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So broadly speaking, white reflects radiation and black absorbs radiation. Then why do paler people experience sun damage so much faster than darker people? | I mean I know it's because of melanin but I guess I'm just approaching biology like the amateur physicist I am here and I'd like to reconcile the two! I mean why does melanin end up making skin darker to reflect more light?
EDIT: Thank you all so much for your great answers! Really enjoyed reading the discussions that were started too :) I think the reality of biology tends to be so much more complex than the (relatively) simple scenarios examined in physics, and that's part of what makes it so interesting!
| 2,600 | The purpose of melanin is not to reflect light. Melanin actually absorbs the UV radiation from the sun. Without sufficient melanin the UV radiation penetrates our skin cells and damages the DNA. If you're out in the sun without protection long enough the DNA damage gets severe enough to kill the cells resulting in various degrees of sun burn. | 1,757 |
[Marvel/DC] Why is the Earth so prone to creating and hosting superhumans compared to other planets? | 31 | For the Earth of the Marvel 616 universe, basically, it's because the Earth was apparently an excellent experimental space for ancient space gods, the Celestials. The genome of homo sapiens is very resilient and very malleable, and so makes for good experimental stock.
On top of that, the Sol system happens to be at a hyperspace nexus for several alien empires, and so in their trips through the local group of galaxies it has been embarrassingly easy for other races and entities to find it as they travel to and fro on their various missions. It's a clearing on a well traveled path, as it were.
Lastly, it is a planet full of secrets it keeps from itself. The populace in general is not interstellar, but are advanced enough to live comfortably, and the relatively few beings who do know much of the greater outside universe will actually conspire with alien interests to keep their fellow humans in the dark. If you need a place to hide, do dirt, do experiments, do *anything* you don't want others to know about, Earth is about a good a place as you can get.
Between those three factors, humans have become a stew of various experiments that all started maturing at the advent of the atomic age. | 47 |
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ELI5: Why does deep breathing relax you? | 19 | Holding your breath (or breathing much slower all of a sudden) highly decreases your oxygen intake. This activates a "dive reflex" that also happens when you dive into water. This puts your body into survival mode, decreasing the heart rate, rerouting blood away from the extremities and to the vital organs, and makes your brain calm down. This all conserves oxygen and also happens to calm you down (the brain uses alot of oxygen, so the your body wants to calm it down to conserve oxygen) | 15 |
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[Supernatural] Would home-loaded shotgun shells firing a spray of salt-coated iron/hardwood/silver flechettes be a good all-purpose rounds? | 145 | Many hunters have toyed with the idea once or twice, but the thing about these damn ghosts and whatnots is that there are too many of them playing by too many rules. Even a good multi purpose shot can still only have so many uses and you definitely wouldn't want to go up against some nightmarish hellspawn and find that your buckshot is impotent.
Beyond that, the time it takes to make the shots and the cost in wasted material (using all that silver when all you need are some splinters soaked in holy water) just doesn't pay off in the context of a hunter's lifestyle, we don't have the luxury of abundant time or money.
You'll be better off just researching what you're going up against and tailoring your arsenal in consequence. This is after all a matter of life and death.
That being said, it wouldn't hurt to make a couple of these rounds to load into a sidearm, in case you get taken by surprise. | 77 |
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ELI5: What runs the internet? Is it just a collection of servers? Is there any single place, that if destroyed, would destroy the internet? | I hope i don`t get put on a list for asking this... | 54 | The Internet itself was designed to be completely distributed. It's mostly just a collection of servers, with routers that all figure out the routes to the different servers on their own.
The only largely centralized piece of this is the Domain Name System- the thing that turns URLs into IP addresses. If you took out all 13 clusters that make up the root of that system, you'd pretty well cripple people's ability to use the Internet, although there's enough redundancy in the system that we'd probably be able to recreate it pretty quickly.
The biggest risk is probably someone cutting all of the trans-oceanic cables which would splinter the Internet into an American Internet and a European-Asian-African Internet. | 44 |
ELI5: Why are we so close with Saudi Arabia despite their connections to terrorism? | 65 | They have lots of oil, we want lots of oil. They oppose Iran in the Middle East, we oppose Iran in the Middle East. They spend a lot of money supporting terrorists, we spend a lot of money supporting some of the same terrorists sometimes. They like buying very expensive stuff from us.
All in all, they're bastards, but they're reliable bastards who more or less toe the US line. | 53 |
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ELI5: When an animation studio like Pixar has multiple dozens of people, all with their own styles, working on a project, how do they keep everything uniform? | 11,723 | Usually in animation we have model sheets and motion bibles (terms vary from studio to studio) that tell us how each character expresses themselves, reacts, and moves. Everything from how they look over one shoulder, how they smile, where their centre of balance is, what they do when surprised, and so on.
This helps keep all the work uniform. | 8,725 |
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[Star Wars] Higher death toll in Clone Wars or Galactic Civil War? | Post-Clone Wars media (e.g. Tarkin book, A New Dawn) talk of billions of lives lost during the Clone Wars. In Bloodline novel, they also say that billions were lost in the Galactic Civil War (Empire vs. Rebellion). I was under the impression that even though half of the combatants in the Clone Wars were droids, it was much more widespread than the Galactic Civil War and had higher casualties.
What do you guys think? | 36 | The Galactic Civil war was not a true war until after the destruction of the Second Death Star. The majority of the war was fought using insurgency tactics on various worlds, because the for a long time the Rebels could never hope to match the Empire in manpower or industry. There were true battles, but they were more of the exception than the rule. The Rebels avoided battles as best they could, but they did have to engage in them on occasion.
The Clone Wars were a true war, where pitched battles against two large armies were fought on planets across the galaxy. Even the Umbara Campaign, which used more irregular forces and ambush tactics than the standard battle, was still very much a fairly standard battle. Onderon was the exception, a tactic adopted too late into the Clone Wars to do anything other than annoy the Separatists.
However, because of the brutal tactics the Empire used, the Civil War still might have larger casualties. They destroyed Alderaan and wiped out an entire species using a genetic virus (The Geonosians).
So while Clone Wars undoubtedly has higher casualties from the battlefield, the Galactic Civil War might edge it out due to civilian casualties.
| 33 |
ELI5: New transistor defies theoretical limit. Wut? | http://techxplore.com/news/2015-10-flat-transistor-defies-theoretical-limit.html
Some of this stuff is just going over my head. | 76 | I think what you are becoming confused about it you think they are talking about breaking some kind of law of physics or something. They are merely talking about ways of augmenting the design of current transistors by utilizing methods and techniques that we haven't even really begun to explore, because nobody really seems all that interested in doing so. In this sense theoretical is not really an appropriate word. More like, new theoretical transistor design proposal suggests new capabilities of current transistor designs. | 17 |
ELI5: Why are so many people pedophiles? Is it actually a mental disorder from life experience or are some of us genetically made to be attracted to younger people? | 53 | One thing that's important to note is that humans become capable of sexual reproduction at ~12 years old. The concept of waiting at minimum 6 years before it is acceptable to engage in sexual acts is a VERY recent development and is also culturally specific. | 57 |
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Is it possible to get drunk through your skin ? | Me and my girlfriend just got a fan mister that sits over a five gallon bucket. Is it possible to get drunk through your skin? I figure if I dilute salt in tequila and pour it in this mister it will absorb through my skin like a brine via osmosis?
Just a friendly bet but I need outside science.
Thanks in advance. | 4,934 | Yes, but you would really have to sit in a bath of it for a decent amount of time. Your external skin is pretty impermeable until it gets waterlogged. The ethanol would probably speed up that process, but a quick dip in alcohol, for instance, probably wouldn't do much/anything to you. In the lungs would be a different story, but also likely very painful/irritating. Alcohol also evaporates quite quickly. So, spreading it out over your body, you would probably lose most of it to evaporation before it even had a chance to be absorbed.
Overall, you're probably best to drink it if that's what you want. Some people have been known to administer alcohol via enema, but this is a very bad idea as it can be absorbed very quickly and not processed efficiently by the liver, resulting in very fast alcohol poisoning. | 4,938 |
ELI5: The different types of Catholicism | I was raised Roman Catholic and eventually became an atheist. Anyway growing up I was only ever able to get partial or biased information regarding Mormons, Baptists Anglicans, witnesses, evangelists etc, I've always wondered what the actually differences are, is it just splitting hairs over scripture translations/meanings or is it more than that?
Edit: I had meant to put Christianity in the title, not Catholicism, sorry for the confusion. | 31 | Basically the religions split based on theological or political arguments between the leaders and the flocks just followed along.
For example, in the early days of the Church, the church elders would get together to discuss the finer points of their faith. These were called 'Councils' and named after the city they took place in. So there was the 'Council of Chalcedon' and the 'First Council of Nicaea', etc, where they would debate things like when Easter takes place.
Sometimes those debates ended and everyone agreed, so there was no split, but more often those debates ended with major disagreement and one side calling the other side heretics and claiming the 'One True Faith' for themselves. Since you can't really prove one side right or wrong, the church would end up splitting into parts. For example, the Arians believed that Jesus and God were separate entities, with Jesus subordinate to God, instead of being one entity with two manifestations, as believed by the rest of Christianity.
Other times, the arguments were more political than theological. For example, when the Anglican church broke off, it was mainly because King Henry VIII wanted a divorce, which was against church law. So he broke off the Church of England, made himself in charge, and granted himself a divorce.
Many times, there were both theological and political arguments. For example, the Great Schism between Roman Catholics and Eastern Orthodox dealt with the Filioque clause (deciding whether God and Jesus were one entity in two beings or one entity in two forms, AFAICT) and whether or not the Pope has more authority than the other Bishops. Catholics believed the 'one entity in two forms' and 'pope is supreme', while Orthodox believed 'one entity in two beings' and thought the pope was full of himself.
So, some of the differences are fairly large issues of dogma, others are basically political or splitting hairs, and others (like the filioque clause above) have major debates about whether it's an issue of dogma or splitting hairs (Now is a good time to point out that priests were the original lawyers). Some churches have split and rejoined. More churches have split but are 'in communion' with each other, which means they think the issues are just splitting hairs. For instance, if a Catholic happens to die and get buried by an Orthodox priest, the other Catholics will consider that a proper burial, or if an Orthodox man goes to a Catholic mass the other Orthodox Christians will assume he's fulfilling his duty to attend mass. Finally, there are churches that are not in communion, which basically means they both think each other are going to hell for not being good Christians, like the Baptists and the Catholics.
EDIT: grammar and spelling | 20 |
[Star Wars] What would the galaxy look like without the Jedi or the Sith? | I'm speaking specifically about what would happen to the Force Users in the galaxy. The Jedi and Sith both exist as a way for Force Users to channel their abilities toward a higher purpose, whether that be fostering peace and harmony throughout the galaxy for the Jedi, or building toward the Sith'ari for the Sith.
But let's say the JEdi and Sith never arise, or they're a very small localized faction. Would we have more families like the Skywalkers where the Force Users have children and so pass on their Force Sensitivity? Would there eventually be "Force dynasties" that would rule entire Solar Systems? | 64 | Before the Jedi and Sith rose and began destroying galactic politics most Force Sensitives spent their entire lives never knowing their true potential. Luke was just thought to be a good sniper and pilot before Obi Wan finished with him. You would hear takes of remarkably skilled warriors, but not crazy samurai monks.
A few would form holy orders like any other, and many existed and still do by the time of the Fall of the Republic. They wouldn't nearly spend as much time meddling and more time meditating. | 50 |
ELI5: Why don’t the FBI or other 3rd party agencies investigate cases of police misconduct, wouldn’t this cut down on “no evidence of wrongdoing” reported by departments investigating their own people? | 28 | They do. The FBI has a big public corruption unit.
In cases like police brutality or racial bias the justice department also investigates but since rules about police brutality are written at the state and county level there’s not much the justice department can do except work out what’s called a consent decree where a department acknowledges they should change their ways because otherwise they might lose federal funding. | 20 |
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[Harry Potter] How would the Ministry respond to the existence of magic being leaked on the muggle Internet? | Wizard society, including the "experts", seems to have a very shaky grasp on muggle technology, and simultaneously obliviating the whole planet and hunting down any physical records seems a big ask. Does the Ministry even have international jurisdiction? | 63 | Counter-disinformation, and hard-boiled skepticism.
Imagine if James Randi was actually a Ministry wizard ...
Remember, a big part of their job already involves cover-ups. In a world like that, the people hollering the loudest and with the best solid logic about how there's no such thing as vampires and werewolves ... are vampires and werewolves.
| 62 |
Why is the letter "Y" sometimes a vowel? | 94 | Even though we label *letters* as consonants or vowels, it's really only *sounds* that are consonants or vowels. And thanks to English's screwy writing system, "y" can be either - at the start of "you", it's a consonant, and at the end of "try", it represents a vowel (well, a diphthong, so it's sort of two vowels strung together quickly - aah to eee). In the word "tray", "ay" represents a diphthong, as well, but you can say that the "y" is just one vowel of the pair. That's also why "w" is sometimes included as a vowel, in words like "how", where the "ow" is a diphthong that goes from aah to ooo. | 69 |
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CMV: People who falsely use religious exemption as a reason to not get a vaccine are making things worse for people with legitimate religious reasons and hurting civil rights progress | There seems to be a lot of high profile people claiming religious exemption for getting the covid vaccine. Many of the people requesting this exemption seem to have only recently 'become very religious.'
I believe this will make things worse for people who need legitimate religious exemptions and may reverse come civil rights progress since the 1960's. The mechanism is that religious exemption will not be taken as seriously and seen as a way to get out of things you don't want.
For example, the head coach of WSU is [claiming religious exemption](https://www.seattletimes.com/sports/wsu-cougar-football/decision-coming-soon-on-wsu-cougars-football-coach-nick-rolovichs-future-in-pullman/). This seems like a selfish act because the impact it will have on his team and this issue of civil rights.
What makes all these requests seem false is that most religions support the vaccine.
Edit: Thank you for discussing. My opinion still holds, but I was convinced that there are religious leaders in the US that do not support the vaccine. The way I worded 'most religions support the vaccine' is a little vague. I mean that religious leaders of the major religions (i.e. most of the religious population) are supportive. I'm taking a break now. But first this quote:
*“There is no credible religious argument against the vaccines,” \[* Rev. Robert Jeffress of First Baptist Dallas \] *said via email. “Christians who are troubled by the use of a fetal cell line for the testing of the vaccines would also have to abstain from the use of Tylenol, Pepto Bismol, Ibuprofen, and other products that used the same cell line if they are sincere in their objection.”* | 23 | >legitimate religious reasons
That in itself is debatable - not only as a statement itself (I would argue that there are no legitimate religious reasons for anything that affects anyone but yourself), but also based on the simple question who gets to decide what's legitimate.
Is the Satanic Temple claiming religious freedom as a way to circumvent the abortion ban in Texas "legitimate"? What exactly constitutes a "legitimate" reason? | 40 |
Post Doc Dilema | I just received my PhD and am currently exploring employment options. My dilema is this: my wife is finishing her last two years of medical school in a town in which it seems my only option is to reamin in the same lab that I did my PhD in for 2 years, or work in small-time industry as a low-level researcher. Or, we can spilt up our little family (we have a toddler) and I can get a more substantial post-doc far away from where I am now. I am trying to decide if it is worth it to leave my family for a couple of years, and alternatively, how much staying in the same lab for that time affect my academic career. Any advice would be appreciated. | 24 | I don't know your field, but your wife is probably gonna make more money as an MD, right? If that's the case, maybe prioritizing her career is more important for your family, meaning that your staying with her and helping her with raising your child would probably result in better career outcomes for her (more time devoted to studying, better residency options probably, etc etc). Not to mention the benefits for your child of having the father around every day. And hopefully a better marriage overall. You can probably build your CV and publications at this place too in the next two years. And then you'll look where to move together. | 62 |
Can you have two colds at once? | 18 | Yes, of course. Not just colds, you can be infected by multiple pathogens at once, which is one of the reasons why doctors might sometimes prescribe antibiotics to someone who is afflicted with a cold - to eliminate any bacterial infections potentially active even if it won't affect the virus. That's also the point of broad-spectrum antibiotics, when doctors prescribe that, it's because they suspect that a patient is infected by multiple bacterial infections at once. | 13 |
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[Batman] how can the riddler stay relevant in this age of information where you could just google his riddles? | I mean a cop can just Google his riddles or something, or a bystander can just post them on batreddit and the internet would just solve it in a couple minutes | 728 | Most of his riddles are context-sensitive clues to what he's up to, not well-known riddles. If he does ask you what has four legs in the morning, etc, he's doing so to pass the time or amuse himself, not as part of his MO. | 866 |
ELI5: why does 85 degrees Fahrenheit outside feel warm, but 85 degrees Fahrenheit water feel cold? | 55 | The feeling of hot/cold is not a measure of the absolute temperature of what you are touching. It is a sensation that tells you how much heat your body is losing or gaining.
Air, for various reasons, doesn't give or take away heat as efficiently as water. In 85 degree air, your body's natural ability to generate heat keeps up with, or even exceeds, the heat you are losing to the air, so you feel warm. The water, on the other hand, draws a lot of heat away from you right away---faster than your body makes up for it. Since you are thus transfering heat away, you feel cold. | 39 |
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[South Park] Why did the aliens who set up Earth as a reality show allow a poor kid from Africa and Sally Struthers to get their hands on interstellar travel technology? | That just seems like it runs a major risk of allowing themselves to be discovered. | 71 | It was a 2 part crossover with the popular sitcom "Everyone marklars marklar". Both shows got a little ratings bump from it, but it was a short term thing.
They tried a similar cross over with "who wants to be a member of the galactic federation " but the earthlings crashed out in the first round and the producers pretty much abandoned all further crossover plans. | 49 |
ELI5: I understand that Ebola has been around for a long time, but what caused this sudden spread of the disease? | 19 | Unlike previous outbreaks that happened in rural, isolated areas which burned themselves out, this one managed to spread to a large densely populated area with poor sanitation and terrible healthcare services. Throw in poor education, lack of basic knowledge of the illness, superstition, burial rituals that evolve touching the bodies of the dead and you have the perfect conditions for it to spread. | 21 |
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[Mass Effect] Would the Reapers've ignored Earth if we never found the Charon Relay? | I think first contact happened 27/29 years before Eden Prime, so what if Earth's space program took 35 extra years to discover the archives on Mars?
Aside from the Yahg, who else could remain? Is it possible we'd have Vorcha on every world in the Terminus system, just like we've got tresher maws all over the galaxy? Would the Virtual Aliens be spared, or considered space faring AI? | 40 | Remember that it can take the Reapers a century or two to complete their "project". So Earth discovers the relay 35 years later... and ends up in the middle of an ongoing Reaper purge, too late to do anything about it.
But that's besides the point. The Reapers' setup is meant to encourage Galactic civilisations to centralise. That's what the mass relays and the citadel are for. This means that as soon as the Reapers take over, which normally means they immediately take control of the citadel, they have access to the collected *data* of every species that made it to the citadel.
And that data will include records on civilisations that are of interest, that might reach the citadel some day.
It's not unlikely that Earth is on that list.
Even beyond that -- once the Reapers are done, well, reaping, they may well travel through *every possible relay* to check on the local system beyond.
They'd find Earth.
| 15 |
[Star Wars] Can a Jedi do a Mind Trick without wiggling his fingers, or is it just the way the power is activated? | On a related note, is [the claw hand gesture](http://i.imgur.com/BEIFunB.jpg) really necessary for a Force Choke? | 42 | No, the hand gestures aren't strictly required. They're more of a useful technique for focusing the mind in the specific way required to use that power.
It is possible to use powers without gestures, just more difficult. A good example is when Luke levitated C-3PO while tied up. | 50 |
ELI5: Why is the drinking age so high in the US? | I'm from the UK, where the legal drinking age is 18 and am curious as to why it is so high in the US.
I've read a few ELI5 threads, but most talk about the laws behind it and why states complied. **I'm more interested in the science behind it: why do the US see alcohol so dangerous for under 21s?** | 30 | Drunk driving. No other nation in the world has access to cheap cars, cheap gas and cheap insurance like the United States. Ours is a car culture. It is expected that at 16 you will have access to a vehicle and own one as soon as soon as possible.
The US is a different world when it comes to the ability of our population to drive to different locations for work, school and play at a whim. Mobility of residence is a by product of our individual independent nature.
Public transportation and dense population housing is available only to very select geographic locations. Our national policy on drinking age was finally dictated in the 1970s through the availability of highway building funds to those States with an over 21 drinking age.
| 50 |
Why does USA not have any container ports among the top ten busiest when it is the biggest importer of goods? | https://en.wikipedia.org/wiki/List_of_busiest_container_ports
https://en.wikipedia.org/wiki/List_of_countries_by_imports | 96 | There's a couple of things at play:
Firstly, the US only has the second largest volume of container traffic in the world, at 55m TEU and behind China at 242m TEU. The next largest ones are roughly the same as the US and include South Korea, Japan, Malaysia, and Singapore - which are all manufacturing hubs that chiefly deal with exports (except Singapore which is a transhipment hub). These countries are pretty small, and hence they dominate the rankings (except China which dominates because it has 4.5x the traffic of the US). For example, Singapore has roughly the same amount of volume as the US, and all of that goes through one port. In fact, of the top 20 ports in the world, only 4 are not from that country group.
Secondly, US ports are pretty bad, on the Container Port Performance Index, the first US port comes in at #53 while Chinese and Japanese ports dominate the list. For example, the largest port in the US, the Port of Los Angeles, has Average Turnaround Times (ATT) of about 2.5 days. The port of Yokohama has 9.5 hours, and the busiest ports in the world (Ningbo, Singapore, and Shanghai) all come in at between 10-15 hours. Much like the airports, American traffic infrastructure mostly dates back to the 70s and is plagued by poor labour quality and severe underinvestment. | 111 |
ELI5: Why do we find vibrato to be pleasing? | 29 | So, it's actually really interesting—if you listen to pieces from the Baroque or Classical periods, vibrato is never used because there was more of a focus on perfect harmony. In the late classical and Romantic era of music, these rules were broken for the sake of expression. IMO, it tends to add a warmth to longer notes especially because of the fact that hearing the slight wavering of a note with vibrato is perhaps less drone-like than a perfect sine tone. | 20 |
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[Judged Dredd] Whose life in Mega-City One is not terrible? | So evidently the unemployment rate is something like 90%, and there is this big industrial core which is able to sustain the Judges. To that implies that *SOMEONE* is making money here.
So who is it? Who is Employed in this universe? What do their lives look like? | 21 | The phenomenally wealthy live in palatial estates, their lives a panorama of life's pleasures. They have armed guards to defend them and the Justice Department leaps to defend them against the poor. Judges who attempt to Judge the upper class frequently find their arrests invalidated and themselves reassigned to slums where they will never have the chance to do that again.
Haha, what a wild, fictional world. | 39 |
ELI5 How was it possible for a heavily armored warrior to die in a battle? They couldn't get stabbed with neither swords nor arrows, could they? | 20 | Heavily armoured doesn't mean impervious to attacks. If they where truly impervious, they'd need a armour casting so heavy they wouldn't be able to move at all, at least with the metals and compounds used back then.
Stabbing through openings in the armour was one way of doing this, another was simply bludgeoning the enemy with a maul or a equivalent.
Armour quality is also a issue, hammering an axe against a poorly made piece of armour would've made either a nice huge dent, or slashed through it to hit the poor bloke wearing it.
Sometimes it was also a matter of using the heavy armour against the enemy. An example of this could be seen in the "Battle of Hemmingstedt" in Denmark, year 1500. A army of peasant took on the royal army, and won, even though they where (comparatively) lightly armoured. They achieved this through fighting in a marsh, and by having flooded the area prior to the royal army's charge, making the heavy armour cumbersome and hard to properly fight in due to the conditions, and the marsh made it near impossible to fight in a proper front, making knights and footmen easily outmanoeuvred by the lighter peasant. | 60 |
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ELI5: If we don't think homosexuality can be 'cured', then why do we think pedophilia can be treated? | 3,334 | We don't. The argument is that you have two options:
Let pedos come out, talk through their frustration with other people, and get support, or you can call them monsters, say you will arrest, hurt, or kill them if you find out that they are sexually attracted to children, and force them to deal with their problem on their own, which is fairly well proven not to work well.
It's not about a "cure" it's about support and education. | 2,894 |
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[John Wick]What makes John so special? | The guys just killed some of my men and I’m planning on gutting the fucker; he’s just one man, right? Can’t be too hard to kill? Why’s everyone so scared of him?
EDIT: I am so.Fucked. | 374 | What you want to do is pay out anything you promised your men to their loved ones after death and pretend that it never happened. This man single handedly put the Russian mob in power in New York then single handedly killed them years later and he had been out of training and retired for years prior to that feat. John wick posses something ordinary men do not.
He is a man of focus. Determination. Once he is set to a task it is completed. He has never failed. A 100% success rate. No one. No one in your industry has that. He is cream of the crop. He once killed two men with a pencil. *a fuckin pencil*. Who the fuck can do that!? But this is not the worst part. Everything I've just described, if nothing else, is *watered down*. | 367 |
[Star Wars] Why do Jedi and Sith use such an inefficient training model? | Why do Jedi Masters only train one apprentice at a time? Even if the Master trains more than one during their lifetime, this is still a really low replacement rate. And Sith are even worse. Only training one apprentice EVER before getting killed by them guarantees a 1 to 1 replacement rate AT THE VERY BEST, assuming absolutely nothing goes wrong. If something DOES go wrong, and Jedi or Sith die in large numbers for some reason, those numbers will either take a VERY long time to fix for Jedi, or are guaranteed to NEVER be fixed at all for the Sith. I know it's "tradition", but how did such a flawed system even become tradition in the first place? It would be far smarter to train small teams at a time, maybe with one Master leading a team of 5 or 6 apprentices at once | 16 | So we can just ignore the Sith, they are doing it that way on purpose. 100% so that there are only 2. Thats the way they want it.
As far as the Jedi you are incorrect. We see small teams of younglings being taught collectively. Its only later training that is one to one. That training only takes about 5 years. A Master can have numerous apprentices over the years particularly when a master can live to be 900 years old.
Yes its slow. Its not meant to be fast. Its meant to get it 100% right not mass produce an inferior product. No Jedi wants another force user out there not dedicated to the Jedi cause because they fall to the dark side.
They are only training the most adapt force users as it is. There aren't enough candidates to bother with more than 1:1. Even using human lifespans a Jedi could train 8-10 other Jedi in a 40 year career as a master. | 54 |
ELI5: What is "space time" and how does it "bend"? | I've heard the term "space time" thrown around, and that gravity "bends space-time" but how does that work? | 18 | Spacetime is exactly what is sounds like. You probably have an intuitive grasp of “space”. You also probably have an intuitive grasp of “time”.
When you combine the two and look at *where* and object is at any given *moment*, you’re looking at the object’s path through spacetime. It’s pretty much just that. Spacetime is just the “position” (both in space and time) of events.
So why is it important, and why do we combine them together? Well, it turns out that your movement through *space* affects time, and your movement through *time* affects space.
For instance, when you stand still, you’re travelling directly through time, but not through space at all.
When you start moving, you’re essentially “rotating” in spacetime, so part of your motion is through space now.
This “rotation” so that part of your movement is through space actually means you move through time more slowly! (It’s not noticeable to you because you’re moving through space reallllly slowly, relative to light)
Things tend to follow straight paths in spacetime. You either keep moving forward through time, or forward through space, but you don’t usually turn unless you put effort into it.
We’ve noticed that those straight paths “bend” around massive objects though. And every object “bends” the exact same way. It’s almost like they’re not bending at all, and instead they’re all following a straight path, just like you’d expect, and for some reason we see that straight path bending.
It turns out the “bend” around massive objects can be perfectly described if you think of *spacetime itself* bending around massive objects, and everything just following a straight path in that bent spacetime.
Why does spacetime bend around massive objects? We… don’t know. We’ve observed some effects that can be perfectly described and predicted by the math that you get if you assume spacetime bends a certain way. Black holes, gravitational lensing, gravitational waves, all stuff that we can predict perfectly by assuming spacetime bends. We know it *does* bend because of these perfect predictions. Why it bends? No clue.
It’s possible we’ll come up with a deeper theory of reality that explains spacetime bending. As of now though, the best we can really do is say that it does. | 23 |
Blue stars burn hotter than yellow or red stars, if that's the case will that increase the habitable zone around those stars? | What would the atmosphere be like on this planet and what could we theorize the day or night cycle would be like on a habitable planet with a different colored sun? | 141 | One thing to note is that blue stars last millions of years rather than billions for yellow stars or trillions of years for red dwarfs. The odds of life developing around a blue star in that short time frame drastically decreases the chance that there is life on a planet in its habitable zone. | 84 |
ELI5: Why do we need to send a test rocket to the moon when we've already been there? | I see all the excitement over the Artemis launch, but I'm not understanding why a test rocket is needed before sending humans to the moon when we've already done this decades ago? Why can't we go straight to sending humans back up there? | 1,331 | This particular design of rocket—the "Space Launch System"—has never flown before. First flights of rockets are typically the riskiest, because ground-level testing can never perfectly replicate the actual conditions of launch and spaceflight. If there is a fatal flaw anywhere in the system, you want to find out *before* you seal a bunch of live humans into the vehicle atop hundreds of tons of flammable propellants and send them into the vacuum of space for over a week. | 2,024 |
[Guardians of the Galaxy] Why is Groot limited to "I am Groot", no more, no less, without any permutations of that phoneme inventory? | Why can't he say words like "root" or "grew" or "tomb" or "ma'am"? | 16 | Maximus the Mad once claimed that "the mature dendritic form" of Groot's sound-producing organs is stiff and heavyweight. Consequently, he can only produce a few baseline sounds. However, there's enough nuance to how Groot produces these sounds that he can convey enormous amounts of meaning. Not many are practiced in picking up on this meaning, though, and so Groot's (alleged) genius often falls on uncomprehending ears.
Maximus also claims (in answer to your question) that Groot's meaning is contained in the "sigh of breeze" beneath his repeated phrase. This suggests that "I am Groot" is just the tip of the iceberg, and his expressed meaning is carried more alongside the phrase than in it. It may be that we rarely, if ever, hear other phonemes because "I am Groot" is just a frame over which is stretched the true vast canvass of his language. | 33 |
ELI5: I have heard that Grand Central Station has enough radioactivity to fail a nuclear power plant inspection. If this is true then why do we not feel the effects? | 1,229 | You've misunderstood the point of that little piece of trivia. The point is not that Grand Central Station is very radioactive. It's that nuclear power plants *aren't.*
Grand Central Station was built with a lot of granite. Granite naturally contains radioactive elements, including uranium. These elements decay, emitting radiation.
But they don't emit *much* radiation. In fact, they emit very little. The half-life of uranium is four and a half billion years. It's *barely* radioactive.
And nuclear power plants release even less radiation than that.
That's the point. | 2,316 |
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[terminator] Say a Terminator actually kills John Connor... | What's it's endgame? It accomplished it's mission now what? | 40 | It would then go about and kill off secondary targets: Other Resistance leaders. John might've been the Wily, but there's still eight bosses to take down. And a few minibosses.
Assuming it manages to do that, it would then go into hiding, like at the bottom of a lake or in a cave system, until Judgement Day. At which point it would emerge. | 35 |
Eli5 how does the eco setting on a washing machine save energy and water by washing the laundry for *longer*? | Edit: Thank you to everyone that replied! | 60 | The motor of the washing machine uses very little power when it's just moving the clothes around. It's a bit more during the spin cycle, but that doesn't last very long.
The vast majority of the power is used to heat the water, so if you can use a lower temperature and/or less water and instead just have the motor do its thing for a longer time, you use less energy (and water) overall. | 72 |
ELI5: Would people who are more intelligent, beautiful, and/or social than average be considered more evolved according to the theory of evolution? | I understand that all of these characteristics are relative or can be considered as constructed by the society. However, the majority of us can agree whether a guy is more handsome than another regardless of his race or nationality. Is a "handsome" guy more evolved than an "ugly" one?
Thanks | 33 | There is no "more" or "less" evolved; there is only *how fit they are to their environment.* But attractiveness can indicate certain markers of health:
There are lots of metrics and measures for "attractiveness." But there are definitely several that are hard-wired and purely biological, rather than cultural or social. And probably the largest and most influential of these is facial and bodily symmetry, where the sides and hemispheres of your face all match one another. This is not *the only metric of attractivness*, but symmetry is a huge part of that "wow" factor you feel the instant after looking at someone very attractive.
Chances are you see attractive people every day; but every once and a while, you've probably seen someone that was almost *otherworldy* attractive. Usually this beyond sexual - you can probably equally identify these factors in men and women, regardless of who you are sexually attracted to. These people are just instantly, magnetically attractive, well beyond the limits of attractiveness we're used to. In these cases, you're seeing someone who is on the very edge of the bell curve in terms of phenotypic expression of symmetry and genetic markers for health and fertility.
Symmetry is cross-cultural. In every culture and society, people with high degree of facial symmetry are considered more beautiful (there is also a theory that the reason "dancing" evolved simultaneously in many separate isolated human cultures was as a mating strategy to demonstrate excellent balance and coordination, which therefore indicated your body was highly symmetrical).
Facial symmetry is largely indicative of how healthy you were as a fetus. A growing human fetus can be subjected to a number of various illnesses and diseases that will disrupt the process of symmetrical facial and body growth.
People who are symmetrical, therefore, may be considered biologically "healthier". From a primitive perspective, these people would be better to procreate with, because your child with them would be more likely to survive, because its healthier in the womb.
Scientists believe there are actually other ways your immune system comes into play in determining attractiveness. The unwashed scent of a potential mate contains certain markers of their immune system. Several studies have shown that you are *most likely* to find someone attractive who has an immune system *much different than your own*.
This actually makes perfect sense, because again, your brain is selecting an individual *with whom your child would be most likely to survive*. If you combine your immune system with one much different than yours, you're giving your child the broadest possible immune system to fight off many different diseases (and also be more likely to develop into a symmetrical, attractive child).
Keep in mind though, again, that these are all generalizations. Symmetry doesn't *always* indicate health. And there are many, many other factors overlaid on top of this with which we ultimately determine attractiveness.
But your brain is *extremely* quick at picking up very small cues. So if you're ever out and about, and you encounter that rare person that is just so impossible attractive that they strike you like a bolt through the heart, where they almost seem like another race - in all likelihood, what you're seeing is just a perfect combination of symmetry, strong immunity, the perfect phenotypical expression of "good health."
**TLDR; no they're not more evolved: they simply have more physical cues indicating they will make a healthy, immunologically sound baby**
| 34 |
ELI5: What do computer scientists research in academia, as opposed to industry? | So I was just wondering this today after listening to a seminar from of my CS professor's about his AI research. The talk was fascinating and intelligent, but it also seemed like something that could easily be developed by a tech company for profit. Most professors of any type have a Ph.D. and they typically have teaching responsibilities, but how does their research differ from say, some of the AI research and development coming from Google? | 26 | Most university researchers have research budgets because they wrote a research grant proposal to study something. They have papers to publish, and their research gives them things to write about, and their students topics to study.
Most corporate research depends on the company's products. Product A needs feature B so there's someone doing research on "can AI do B?"
Academic research is "B might be possible with AI". | 17 |
What kind of damage would a collapsing space elevator do to earth? | In a few anime a falling space elevator has a potential to destroy the planet but what kind of damage would it really do if the elevator was 60,000 miles high? | 71 | A space elevator consists of three parts: the terminus up at geosynchronous orbit (or a little higher), the car that moves up and down, and the cable.
The terminus wouldn't fall. It's essentially just like a satellite that orbits freely.
The car that moves up and down would most likely mostly disintegrate on entering the atmosphere, in much the same way that the Space Shuttle Columbia did. In terms of effect, you can probably compare it to the meteorite that landed in Russia a while back.
I think the largest risk is going to be from supersonic whiplash from the cable, which would be under tension. How that behaves depends on where it breaks. | 23 |
CMV: capital gains should be taxed as ordinary income | *(Not many people seemed to like my previous idea, so I'm turning it on its head.* [*https://www.reddit.com/r/changemyview/comments/x9clus/cmv\_all\_retirement\_accounts\_should\_be/*](https://www.reddit.com/r/changemyview/comments/x9clus/cmv_all_retirement_accounts_should_be/)*)*
Capital gains and dividends should be taxed as ordinary income.
In order to protect the middle-class earner from their retirement savings being eaten by taxes, everyone should be able to contribute to a tax-free retirement account (like a Roth IRA, but doesn't have to contributed only from income) with an annual cap, maybe $50k. Current retirement accounts like 401ks would be phased out. The step-up in basis upon inheritance would also be ended, so the estate would need to pay capital gains taxes upon the owner's death. (There could be a maybe $1-5MM capital gains exclusion upon death to make sure the family house gets passed on.)
This would tax the wealthy and ultra-wealthy much more on their assets and also make the entire taxation system simpler and more fair, because everyone would have equal access to retirement accounts and everyone's income would be treated similarly. | 22 | Short term capital gains and dividends are already taxed as regular income (in the United States). The issue with long term capital gains is inflation. Imagine if you buy a share of a company and then sell that share 20 years later for the exact same *value* as you paid for it. Since there has been significant inflation over 20 years, if you paid $10,000 for it you could sell it for $13,000 and still have the same value, the same purchasing power. You would pay taxes on that $3,000 of "gains" even though you did not gain any value. It sort of makes sense to discount the long term capital gains rate to compensate, though it isn't really the right way to deal with it. Long term capital gains should be adjusted for inflation and then taxed at the same rate as regular income. | 58 |
Why is Papua New Guinea considered part of Oceania, and Indonesia considered part of Asia, when they share an island? | 47 | It's an arbitrary measurement, but it is likely due to the fact that Papua New Guinea was under Australian control until 1975 and is still strongly within Australia's sphere of influence (particularly in aid). This is likely why it is set as the border between Asia and Oceania/Australia/etc as it has stronger ties with its southern neighbors than its western and northern ones.
Edit: Forgot you were five. So people aren't really sure where continents start and end, so they put the borders where they think it makes the most sense. Papua New Guinea likes to talk to Australia more and has been better friends for a longer time than with Indonesia, so people thought that they would like to be in Oceania because Australia is there. Indonesia isn't good friends with Papua New Guinea and spends more time talking to its other neighbors like Malaysia and so people thought it should be in Asia. That's why people thought that Papua New Guinea and Indonesia should be on different continents even though they share an island. | 25 |
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[Gattaca]Are Olympics still a thing? | And why did the doctor care about the scars of eye surgery but didn't care about the scars on the legs? | 38 | I imagine so, pro/competitive sports is still a thing since what's his face was a diver before his accident, even if you have perfect genes for a sport you still have to train to realize your potential. | 13 |
ELI5: if ISIL is "heavily recruiting online" like I keep hearing shouldn't it be relatively easy to infiltrate their ranks with undercover agents? | 20 | Infiltrate them? Yes. Infiltrate them in a way that could actually be beneficial and ethical? No.
ISIS works with a cell structure. If you get recruited, you end up in the lowest level cells. Only the high level cells have any sort of valuable information. The way to work yourself up to these high level cells is to constantly apply yourself to their dogma and prove your worth. You know, by killing people. There is no agency in the world that is going to send their agents to kill lots of innocent people in the hope that maybe some day they end up high enough in the structure to maybe pass on something valuable. | 27 |
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ELI5: Why don't our "breathing muscles" become tired like any other muscle would if used at the same rate for years? | If we flex a muscle enough times, it will become tired and hurt eventually. Why doesn't this happen with the muscles responsible for breathing, they are "flexing" continuously for as long as we live. | 25 | Your premise that if you flex a muscle enough times it will become tired and hurt eventually is not true.
Muscles contain a mixture of different types of muscle fibres (cells). Some are better at generating high amounts of force quickly (fast twitch) while others are better at resisting fatigue but generate less force more slowly (slow twitch).
Your diaphragm has a roughly equal distribution. This allows you to breath faster/more deeply when you expert yourself (e.g., exercise) and also breath more slowly and less deeply at other times when you are basically resting.
When resting (not just sleeping but when you aren't exerting yourself such that you need higher respiration rates) the slow twitch fibres are capable of contracting continuously without fatigue because of several characteristics of the fibres including a smaller cross-sectional area, more capillaries, more enzymes that allow aerobic metabolism.
TL;DNR: The diaphragm (muscle involved in breathing) has muscle fibres (cells) that are highly resistant to fatigue. | 17 |
How far does an insect (like a beetle or a fly) travel from the place they were born in? | 7,977 | It varies a lot. Most non-migratory ants for instance never venture more than a few meters from the place they're born.
Others travel considerable distances. Monarch butterflies, for instance, migrate 2500 miles to survive the winter. | 3,130 |
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I used some menthol crystals for a cold, and after about an hour this thing formed. What happened? | I'd used some of [these](http://i.imgur.com/825OH.jpg) crystals in boiling hot water, and they'd seemingly dissolved but I came back to find [this thing](http://i.imgur.com/fHSDl.jpg) floating in the water. I'm curious as to how it formed.
Thanks! | 103 | menthol has lower density than water. so it floats. it is not soluble in water, so it separates. it also has a crystallization point that allows it to crystallize at reasonable temps. so, when the water cooled, the menthol floated to a bit in the middle, crystallized. that's all. | 58 |
ELI5: How do they make vitamin tablets? | Where does the vitamin come from and how do they make it into pills? | 17 | Vitamins can be derived from plant or animal products, or produced synthetically in a laboratory. Vitamin A, for example, can be derived from fish liver oil, and vitamin C from citrus fruits or rose hips. Vitamin C is water soluble, so all you need do is crush or grind the plant material and then shake it up with water. A common method is to grind the material with some clean sand in a mortar with a pestle. The material can then be filtered or centrifuged to get rid of the debris. The vitamin C will be in the water. The water is removed and what is left is made into tablets.
Producing it synthetically just means that we have learned what basic chemicals make up the vitamin. Those chemicals in a very purified form are mixed together and put into tablets.
Most commercial vitamins are made from synthetic vitamins, which are cheaper and easier to produce than natural derivatives. So vitamin A may be synthesized from acetone, and vitamin C from keto acid. There is no chemical difference between the purified vitamins derived from plant or animal sources and those produced synthetically. That said, some people react differently to the different versions and have a preference for one type or the other. | 10 |
Is there a correlation between 1 cal = 4.184 J and water’s heat capacity of 4.184 J/g°C? | I’m in an online introduction class to chemistry. Today’s lesson covered energy, temperature, heat capacity and such. There was one part of the lesson that said 1 calorie is equal 4.184 joules. Later in the lesson there was a part that said water’s heat capacity is 4.184 J/g°C. I noticed that numbers were the same between the two. No where in the lesson did it address this similarity. So I was wondering if there’s a reason that these numbers are the same or if some there is some kind of correlation out side of having joule as part of the measurement? Or is this just coincidence? | 74 | It's not a coincidence at all. The "calorie" unit is defined to be the amount of energy required to increase the temperature of 1 gram of water by 1 Kelvin (or °C, which represents the same temperature increment). As such, it is directly linked to the heat capacity of water.
The heat capacity of water depends on the pressure and starting temperature, so the amount of energy that 1 cal represents changes slightly with these variables. The conversion value of 4.184 corresponds to water at atmospheric pressure with a temperature somewhere around 18 °C. It was picked as the standard conversion rate between calories and Joules. | 197 |
Are 2FA codes random or is there an algorithm in place to make the digits more human-friendly? | Hey,
At my work, as in most tech companies, we use the security tokens to log into certain systems as a 2-FA.
For those who don't know, it's a little device that displays a 6-digit code that changes every 30 seconds and you use it to log into work-related systems. Some sites use your phone for this, steam for example. Others use google authenticator that also has 6 digits.
​
My question is since these codes need to be input manually, are they more human-friendly or indeed, completely random?
I have noticed on the security token I use for work, since I use it way more often than any other 2FA, that often the code is somewhat easy to remember. Often you get codes like "556 789" or "222 001". Digits repeat, follow one another (478), are close on the keyboard (369) or "skip" (727 545).
​
Is it normal practice to incorporate some kind of algorithm into these code generators to make it easier for humans to copy them or are they completely random and my confirmation bias is only remembering the "good" combinations?
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Thanks. | 47 | The codes don't have a discernible pattern in them. While you may not technically be able to call them random, effectively that's what they are.
2FA systems that produce a new code every 30 seconds are part of a system called "Time-based One-Time Passwords" or TOTP. TOTP works by combining 2 elements to generate the code: First is a shared secret key that is present in both the authentication device (which can be a separate device or a smartphone app) and on the server. This secret key is unique for each user. The second component is the time. Typically measured in 30 second intervals.
When you press the button on the device or open the smartphone app, the code is computed by taking both the secret key and the time and running them through a certain mathematical function called a "cryptographic hash function". A cryptographic hash function is a function that can take any number or data as input and outputs a number in such a way that it is impossible to reverse the process and figure out what the input was for a given output. With a good hash function, no matter how many outputs you collect, you should not be able to deduce or brute force what the input was, even if you have some partial information about it, for example that the outputs are TOTP codes that belong to consecutive time-steps.
So when you try to use this system to authenticate, both the device and the server use the shared secret key and the current time to compute the code. You then input the code and the server can verify that it is the same as what it has computed. If it is, then that proves that you possess the shared secret key. The secret key is crucial in this process. If an attacker obtains it, he will be able to perfectly reconstruct the authentication codes.
Since time is a variable in the algorithm, it is important for both parties to have a clock that is synchronized. Unfortunately, clock synchronization is not something that is easy to do between devices that aren't directly connected. So to compensate for this issue, the server may allow for not just the current code to be accepted, but also codes corresponding to one or more 30 second steps backwards or forwards. If the server detects that a user is having a clock that deviates slightly, it could store this offset in the user's profile and use that information in the future. This would allow users with a clock that is gradually drifting further away from the actual time to still use the system. As long as the clock drift between two logins isn't too big, the server can accept it and keep track of it.
The algorithm used for TOTP doesn't care about what digits come out on the other end. There is no bias towards combinations that are easier to enter and the fact that you're remembering the codes that do appear to have a pattern is simply because those are the codes that are the most memorable. | 45 |
ELI5 what happens when I click on "Safely Eject Hardware" in the Windows Tray? | Here's what normally happens:
* I have one (1) USB stick in the computer
* I click the "safely Eject Hardware" thing
* Up comes a window asking me what I want to Eject which lists one thing: "USB Mass Storage Device"
* I have to click on that
* Up comes a window with *three* things in it:
* one of them is "USB Mass Storage Device" from the previous window
* one of them is "Generic Volume"
* one of them is the name of my device
* It doesn't matter which one I click on.
Then it's ejected.
I mean, seriously?
**NB**: my experience is mostly with XP. Maybe it's better in 7? | 61 | If you're asking what happens when you click on the icon, it is just giving you a list of removable storage devices that you can disconnect. The repetition is to make it easier to identify which device you want to disconnect. If you want to disconnect fappy's device, you can do it by type *or* name.
If you're asking why you need to disconnect it, that's because the data essentially exists in two places. And all changes are not made until you eject the device. Imagine you have two buckets, bucket A and bucket B. In bucket A you have some water. You want to pour the water into the bucket B, but instead of waiting to make sure you're finished pouring all of the water from A to B, someone randomly snatches bucket B away. Now, all the water may have been poured into bucket B, and it probably has been because that bit of water pours fast, but then again there may be a bit of a mess to clean up. And water on the floor is very corrupt water. | 41 |
ELI5: Why can sports teams, sports channels on TV, or sporting news on the internet reveal the exact details of sports players' injuries if HIPAA exists? | I thought there existed patient-doctor confidentiality? Why don't you see players suing journalists, teams, websites, newspapers, etc. over violations of HIPAA? Are they exempt for some reason? | 45 | HIPAA only restricts certain types of organizations from revealing health information (basically healthcare providers and insurers, plus their agents). The Hospital---without a release from the patient---couldn't say much of anything about a famous person's injury or treatment, but the coach or the team can. It is also almost certainly part of any athlete's contract that they consent to share health information with the team, probably with only a limited expectation of privacy in return, if any. | 23 |
ELI5: How do clouds of interstellar gas collapse and form stars and planets? | I've been reading Neil deGrasse Tyson's Death By Black Hole. In it, he states "Microwave telescopes allow us to peer inside clouds of interstellar gas that collapse and form stars and planets."
How does that happen and why? | 32 | Gravity. Over time, dense regions in interstellar clouds will begin to form little "clumps" of gas. As the clump gets heavier, more and more matter falls onto it, adding to the mass. The object will also spin faster and faster, forcing itself into a disc shape called a protostellar disc. As the mass of the disc increases, more and more matter falls onto it, making it more and more massive.
Once the disc is massive enough, and the core of the disc compressed enough that the temperature reaches 10 million Kelvin, nuclear fusion begins. The protostar begins to shine.
Planets are formed a little differently; typically from the remnants of supernovae. The same process of gravitational attraction applies, but there is typically insufficient material to get the planet anywhere near big enough to begin fusion. That's what happened with Jupiter; it is a failed star. | 18 |
CMV: In the "trolley problem," choosing to pull the lever is the only defensible choice. | The classic trolley problem: A runaway trolley is barreling down a track and is going to hit five people. There is a lever nearby which will divert the trolley such that it only hits one person, who is standing to the side. Knowing all of this, do you pull the lever to save the five people and kill the sixth?
I believe that not pulling the lever is unacceptable and equivalent to valuing the lives of 4 innocent people less than your own (completely relative) innocence. Obviously it's assumed that you fully understand the situation and that you are fully capable of pulling the lever.
Consider a modified scenario: Say you are walking as you become aware of the situation, and you realize you are passing over a floor switch that will send the trolley towards five people once it hits the junction. If you keep walking off of the plate, it will hit the sixth person, but if you stop where you are, the five people will die. Do you keep walking? If you didn't pull the lever in the first situation because you refuse to "take an action" that results in death, you are obligated to stop walking for the same reasons in this situation because continuing would be an action that leads to death.
Is it really reasonable to stop in place and watch four more people die because you refuse to consciously cause the death of one person?
Many of my good friends say they wouldn't pull the lever. I'd like not to think of them as potentially horrible people, so change my view!
edit: Some great comments have helped me realize that there are ways I could have phrased the question much better to get down to the root of what I believe to be the issue. If I had a do-over I would exaggerate a little: Should I flip a switch to save 10,000 people and kill one? There are good arguments here but none that would convince me not to pull that lever, so far. | 439 | If you don't pull the lever, you are letting 5 people face the consequence of their choice to stand in the path of a trolley. If you pull the lever, you could be killing a person who is purposefully avoiding the trolley.
Your stance requires a utilitarian viewpoint. We could probably save thousands of lives and cure Ebola if we rounded people up, infected them, and tested treatments. Is that a valid approach? | 220 |
[Star Wars] Why are force sensitives so morally extreme? | I searched online for the answer to this, but I couldn't find it.
Why are force sensitives either on the light side, or full on dark side? I know there are grey Jedi, but they seem to be a very small minority of force users. Why is it that, if a Jedi starts to try out the dark side, the temptation becomes overwhelming? They don't seem to behave like normal people, who are usually somewhere in between. | 97 | If a person uses the Dark side, they can be very quickly corrupted by it. Morality is like alcohol, and Force-Sensitives are those on the former-alcoholic knife-edge, whereas others can stray most places and emerge relatively unscathed. | 98 |
ELI5: What exactly Is the Static On A Tv? | I under why static happens.. what what exactly is it? What is it a bunch of black and white dots? | 61 | Background noise of the universe.
So the tv antenna is resonating with the band of frequencies it's designed to pick up, and when we send a specific signal comprised of one of those frequencies the antenna resonates and the tv takes the signal and puts it into all the dots on your screen.
So the antenna is picking up the random times it's resonates by other causes and it's trying to put that random shit on your screen.
This is why the static is often called "noise" and why noise can distort your picture. Like when your ear can focus in on one conversation in a crowd of people talking, the rest is just noise. If you take that conversation away all your ear can then hear is noise until you focus on another sound. | 43 |
ELI5: If the internet is primarily dependent on cables that run through oceans connecting different countries and continents. During a war, anyone can cut off a country's access to the internet. Are there any backup or mitigant in place to avoid this? What happens if you cut the cable? | 22,006 | Think of it like closing an interstate highway. If I-95 suddenly disappeared, you could still drive from Miami to New York; you'd just have to take alternative (longer) paths, and you would be further slowed by all the other cars taking that route instead of I-95.
Internet routing works the same way. There are redundancies built into the system, whereby traffic will take an alternative path if its preferred route is blocked. Now if ALL the cables got cut and there were no alternative paths to take, then yes. The affected continents would be effectively cut off from each other for internet purposes. | 13,230 |
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Do multidimensional (more than 3D) mathematics and physics have practical use that we can face in everyday life? | 63 | Yes yes and more yes!
The mathematics used in multidimensions is really the same thing as saying that the problem is multivariable. In fact almost any real world problem you solve will be more than 3 variables (dimensions). In fact describing one of the the simplest possible situtations, a single point particle moving in a potential is a 6 dimensional problem! (3 variables for momentum and 3 for position)
Imagine the engineering that had to go into cars and planes... the types of models engineers work with to understand dynamics are incredibly complex and certainly more than 3 dimensions.
Nearly every single robot that works in a factory is programmed with models that use more than 3 variables (think of a robotic arm with several joints and all the degrees of freedom it has!).
Models that companies use to look at the stock market are built on hundreds (thousands?) of variables.
Signal processing (internet, phone, television) is necessarily a multidimensional problem.
Bottom line, any time you hear 'multi-dimensional' think 'multi-variable'... and our civilization, with all of its technical knowledge, certainly depends on solving these types of problems. | 49 |
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CMV: There are very few problems with the transgender movement, and most of the people who criticise it only do it to be nasty. | I will list my issues with the transgender movement first, and then those who criticise it second.
-Transgender Issues-
-Things such as hormone therapy are not to be taken lightly. Those who identify as transgender should go through tests and have a fairly long time period, say about 6-12 months in between diagnosis and treatment just to make sure it isn’t just a phase or something they’ll regret. The transgender movement should be accepted, but not largely encouraged as young people are easily swayed and they may believe something about themselves that they will change their mind about later, leading to potentially regrettable life choices.
-Children should be taught about trans people and learn to accept them as anyone else would be, but it should not be pushed upon them by crazy parents and they should wait to come of age (maybe eighteen) before they make the choice for themselves.
Those are pretty much my only issues with the transgender movement, and these criticisms I believe are perfectly normal and fine to have. Now onto my issues for those who criticise the movement.
-Refusal to use pronouns: Okay, I’ll admit the whole xhe/xhem/xher pronouns and stuff like that are daft, but should it be too much of an issue to address someone how they ask to be addressed? If you were speaking to some guy called John Smith and he asked you to call him “John” instead of “Mr Smith” you’d call him by his first name, right? So why should it be any different for transgender people? If someone was called Harry and now they want to be called Lucy why don’t you just call them it? It would be the kind thing to do, instead of just being contrarian and disrespectful. It really makes no difference to your life, it barely affects you in the slightest except for having a bit of awkwardness when you first start using the pronouns.
-Labelling transgenders as “mentally ill”: I’ll be honest, I haven’t done much research into this area, and that’s one of the main reasons why I made this post, however I’ll state my current point on this matter. Calling transgenders mentally ill is just a rude thing to do. It’s got pretty negative connotations, and I’d imagine there would be a better word to describe body dysmorphia with. People who make this statement tend to do so very smugly and matter-of-factly and it’s really obvious from the way they say it that they don’t really care about transgender people at all, they just like having a group they’re allowed to insult and demean. It’s mostly a superiority thing, people label others as mentally ill (transgenders are traditionally left) and they validate their own opinions and feel better about themselves. Instead of doing this why don’t the people who say these things look at it from an understanding angle and try and help transgenders to be able to achieve happiness without drastically changing their lives? I know the answer, it’s because they just don’t care about them and they enjoy mocking them and offending them for no reason other than cheap laughs and a moment of moral superiority.
That’s my opinion on the matter, and I realise it’s probably pretty skewed and biased in favour of transgender people, so I’d like to hear some proper arguments against the movement instead of just the usual vitriol you see in YouTube and Facebook. | 29 | I agree on all points but one: being transgender is indeed a mental illness, the problem here is that mental illness is stigmatized. Many people do use “it’s just a mental illness” as a way of dismissing a transgender person’s experience and brushing them off as “delusional”. It’s just ableism, plain and simple. Mentally ill people still have valid experiences and are just as deserving as sympathy as anyone else, though unfortunately not everyone believes that apparently. | 10 |
ELI5: What is the point of a conductor in an orchestra when everyone knows what they are playing? | 43 | Everyone knows their parts and can play it nice on their own but once you have to coordinate a complex piece of music with lots of other musicians it can be very hard. First of all sound takes some time to travel from one side of the stage to the other. So if you were to base your tempo on someone across the room you will be off and it will sound horrible. So you need to use visuals to find the tempo as light travels much faster. This is why the conductor swings his arms in beat with the music. But there is also a lot of other things that is different each time you play a piece. The performers are in different states of mind, the instruments might be affected by temperature and humidity, the sound changes depending on the room, the audience act differently, etc. So the conductor is "playing" on the performers as if they were a big instrument. If one section of the band is too loud he can tell them to bring it down, if someone gets out of beat he can tell them to they are ahead or behind, some pieces have sections that is deliberately changing beat or does not have a beat and it is up to the conductor to find the right timing, etc. Basically if you have a large group of musicians you need someone to coordinate them to make great music. | 76 |
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ELI5 Stalinism vs Maoism vs Trotsykism | I see these varieties of communism referenced but I don't understand the difference. | 133 | Stalinism doesn't exist. It's basically a slur for anyone who loves Stalin. But usually it references the tendency of Marxist-Leninism.
Before showing what the difference between Marxist-Leninism, Trotskyists, and Maoism (short for Marxist-Leninist-Maoism) you must know what Marxism is.
Marxism is a body of analysis and critique of capitalism. It forms the basis of the worldview of communists and it is the utter rejection of liberalism. Marxism is considered by communists to be a science in that it is a constantly developing theory shaped by a cycle of making theory, practicing it (applying it to the real world), and then changing the theory to accommodate for what works and what doesn't. Marxism also assumes the world to be ever changing so it develops as the world evolves.
Marxist-Leninism is considered to be a major scientific advancement of Marxism and also differs from Marxism in that it isn't solely analysis and critique, but also a description of how revolution should occur, how we organize the workers, how society should look like, and how to continue combating capitalism and liberal ideology after revolution. Some of the major advancements include:
-**Analysis of imperialism**, how rich Western countries maintain overall high living standards, wealth, and decadence by exploiting the Global South (what some people today would call world systems theory, neoliberalism, or 'globalism').
-**The vanguard party**, posits that the revolution must be organized in order to be successful. The most devoted workers form what is called a vanguard party which acts as the central leadership in revolution, and after revolution becomes the government.
-Indepth analysis of the state and how it can be a tool of oppression depending on which class controls it.
-Posits and proves that revolution is more likely and more successful in developing and more exploited Global South countries.
-**The Peasantry is Revolutionary**, it is recognized that the peasantry is also an oppressed class with similar interests to industrial workers. In agrarian societies like Tsarist Russia, uniting the proletariat and peasantry is necessary for successful revolution.
-Creates the idea of **Left wing nationalism** as a nationalism for oppressed people/nations that is compatible with communist internationalism.
-**Socialism In One Country**, the strategy of a socialist state after revolution should be to rebuild and fortify itself against possible counter revolution or invasion/coup/embargo by the West, rather than take an immediate active stance in exporting revolution to other countries.
Trotskyism is in opposition to Marxist-Leninism. Leon Trotsky, Bolshevik revolutionary, believed the Soviet Union was abandoning internationalism and was also losing touch with its workers, so he created a new theory that is based on Marxism, is similar to Marxist-Leninism, but rejects some of the advancements and contributes new analysis of its own. Some of these things were:
-Rejection of Socialism In One Country for **Permanent Revolution**, a socialist state after revolution must immediately devote as many military and economic resources as possible to exporting revolution to the entire world, so as to subvert capitalism as fast as possible.
-Posits the **Degenerated Worker's state theory** which says that the USSR was becoming 'degenerated' or slowly giving way to a new bureaucratic class with interests of its own to the detriment of the workers.
-**United Front and Antifa**, Trotsky was the first person to recognize that fascism was not only worse than liberalism but the greatest threat to communism ever faced. He believed that communists should do whatever it takes to combat fascism, including fighting on the streets AND temporarily siding with liberals (United Front). This is also Trotsky's most important contribution, so important that all tendencies of communism from anarchism to Maoism have accepted it and implemented it.
Maoism, short for Marxist-Leninist-Maoism, is a scientific advancement of Marxist-Leninism as the name suggests. Currently it is the most popular communist tendency in the world, especially in the Global South. Maoism is not as a big jump from Marxist-Leninism as Marxist-Leninism was from Marxism. Here are a list of some of its advancements:
-**Protracted Peoples War**, strategy for revolution which says that the best way to win is to use guerilla warfare and make the war last as long as possible so as to outlast the state and bleed out Western support.
-**The Mass Line**, the best keep the Communist party in tune with the people by taking the unorganized ideas and aspirations of the people and forge policy out of it.
-**Theory of Social Imperialism**, in many ways this is similar to Trotsky's Degenerated Workers State theory but Social Imperialism theory is considered more accurate, developed, and comprehensive. It posits that the USSR succumbed to revisionism (which is the unscientific rewriting of Marxism) and started engaging in imperialism, an act previously thought to be exclusive to capitalism. Many also conclude from this theory that the USSR was no longer socialist after Khrushchev took power.
-**Cultural Revolution**, Mao recognized that a threat to communism would not just come from the outside but also from the inside in the form of revisionism, and if nothing was done to stop it then it would slowly deteriorate and destroy socialism. Cultural Revolution is a method of stopping revisionism by actively finding and removing members of the party and the state who pretend to be communist and do not believe or care about workers liberation, and to continue the fire of revolutionary fervor in the population by having the people take an active effort in fighting dated or oppressive cultural traditions, and destroying positive symbols of the capitalist past.
-**"Class struggle only intensifies under socialism"**, a new understanding of socialism that reinforces the importance of taking defense very seriously and actively. It is said that class struggle intensifies under socialism because instead of strikes, riots, and insurrection, there is now proxy wars, coups, spies, covert warfare, and more. The capitalist class will do whatever it takes to hold power, and so will the workers, resulting in intensified struggle on a global scale. | 69 |
CMV: Bait trucks/cars are a good police operation and I disagree with the backlash they get. | So I just read [this article from CBS](https://www.cbsnews.com/news/bait-trucks-chicago-police-taking-hard-look-at-controversial-program-to-lure-thieves/) after seeing it on my Facebook feed. In Chicago, a police operation to set up a "bait truck", a truck people are misled into believing contains expensive shoes, so that the people who attempt to break into it can be arrested, is facing some backlash. Now whatever can be said about the Chicago police force, I don't understand how this can be criticized. Based on what I read in the article, people believe that this targets minorities and is a breakdown of trust, but isn't it targeting criminals and only breaks trust between criminals and the police? If someone is willing to commit a robbery, wouldn't you rather have them rob nothing of value and get arrested for their crime when they try to rob a bait truck, rather than have them rob something that *is* of value and possibly not get arrested for their crime when they commit an actual robbery?
I don't understand the backlash to this. Bait trucks and bait cars are good ways to catch criminals. CMV
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> *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!* | 15 | Entrapment is generally considered an unethical way to catch criminals because you're creating a situation which is *by design* meant to encourage criminal behavior, then arresting those who are encouraged. Independent of this specific situation, and independent of the legal definition which varies from jurisdiction to jurisdiction, do you agree that at least some kinds of entrapment are unethical? If so, then this boils down to what extent the practice of bait cars in Chicago can be considered entrapment. If not, please explain your thoughts on why you believe entrapment in general is a permissible way to catch criminals. | 12 |
If the symptoms of an illness are typically the body creating a hostile environment to get rid of the infection (runny nose, fever, etc.), what do viruses/bacteria actually do? | Or, what would an illness look like if our immune system didn't do all of those things to destroy the viruses/bacteria? | 28 | Bacteria actually "just wanna live". Since they are living cells hey also have a metabolism like any other living cell, plant, animal, human. What makes them infectious is the materials they secrete - these are poisonous to your body. Of course not all bacteria do this or secrete other stuff that is no danger to your body. So it depends what bacteria you have.
Virii in turn don't actually "live". They are more like dead things like a stone. However, they possess detectors on the outside and blueprints of themselves inside. Once their detector docks with the right counterpart (here a certain cell) they inject their blueprint (virus DNA or RNA) that reprograms the cell to just build more virus shells and blueprints and assembles them into new virii. Then the cell collapses and unleashes the virii into the world. | 14 |
What causes the global cooling after a Milanković cycle? | Hey,
I'm reading about the climate change, and one prominent argument is the connection between global CO² concentration and temperature. Afaik the temperature increases periodically because of Milanković cycles, which causes the CO² levels to rise, which in tern increases the temperature further.
The question I can't seem to find an answer to is this: If the Milanković cycle only kicked of the feedback-loop between temperature and CO² and both are at very high levels, what causes them to decrease again after a certain amount of time?
Thanks! | 375 | Jumping in because I’m not seeing the ice sheet connection in any answer here.
One important detail about Milankovitch cycles is that the slight changes in Earth’s orbit around the sun, the degree of its axial tilt, and the location of the equinoxes in its orbit (these are the ‘orbital cycles’ you hear about) have little effect on the OVERALL incoming solar radiation hitting Earth. Instead, they significantly affect when and where the most direct incoming radiation is hitting throughout the year.
This matters most in the Northern Hemisphere polar regions, where big ice sheets have formed and melted throughout the last 2.7 million years (the Pleistocene Epoch). When the orbital cycles are oriented so that these regions have mild and short summers, snow and ice can linger throughout the year and eventually lead to the formation of large ice sheets (see the Laurentide and Fennoscandinavian Ice Sheets during the Last Glacial Maximum). Now here is the key connection to Milankovitch cycles and CO2: when these big ice sheets form around the North Atlantic, they pull water out of this ocean region and make it saltier, which leads to more surface water sinking into the deep ocean. This pulls a tremendous amount of dissolved CO2 into the deep ocean, where it does not exchange with the atmosphere. This is one of the main reasons why CO2 lowers in lockstep with certain phases of Milankovitch cycles. This dynamic is also a feedback loop, because as atmospheric CO2 lowers, the global greenhouse effect is reduced, which leads to more cooling and further ice sheet buildup.
The reverse happens when the gradual changes in orbital arrangements start lengthening and warming Arctic summers, leading to ice sheet melt and reduced ocean downwelling in the North Atlantic.
Source: Paleoclimate PhD student | 86 |
CMV: I Think Intellectual Property Rights Should Not Apply To Scientific Research | Since intellectual property can be held by multiple people at the same time, one does not have the "right" to it in the sense that if I take it from you you no longer have it. Therefore, the state cannot be expected to guard a property that cannot be taken away without some other justification. This justification goes as follows: since there would be no profit in invention if there was no right to exclusivity, we must form a patent office to ensure profitability which then ensures continued incentives for research.
This argument is essentially passing the buck to the future: we will deny the resource of everyone having access to pre-existing inventions (something I think is obviously useful) because if we do not we will never get anymore new inventions. It made a lot sense when the patent office was founded and the government realized that the amount of inventions was going to be accelerating rapidly. The U.S. had also stolen much from Britain and they wanted to make sure that wouldn't happen to their investors. It became accepted as the right and wise way of business and none could argue the stupendous results that the system produced seeming *ad infinitum*.
But now we are in an age that can look back over the pat 150 years and find a seemingly infinite amount of knowledge in the past and I think that the utilitarian argument has been reversed. The advantages of further research are not going to out-weigh the costs of not having access to so much technology from the past. This is not a certainty by any means, we cannot know what science will discover. What we do know is that high return technology investment has ensured that research and patent control is kept by giant corporations trying to maximize a buck. We also know that the best way to do that, in a capitalist system, is through producing high-tech waste, i.e., weapons . So, even if science does have amazing discoveries to await us, I'm not convinced that they will be that much more useful to humanity than the technology we already have but are not utilizing. If we remove the profit from patenting new technologies, research will have to be channeled into practical applications in order to be profitable. As technology is finally applied freely and the ingenuity of the past is revealed, humanity will enter a new golden age. | 17 | research is really expensive. it costs a lot to research the science and then find applications and then find ways to build those applications.
what doesnt cost a lot of money is stealing those ways of building things and producing the same item, without haveing to do any of the research for it.
companies that do this can put a significantly lower pricetag on their items, becuase they didnt have to pay anything up front. as such, the company who initially created the invention loses a lot of money.
this cycle means that there is no profit in (or even a way to sustain) a company doing research to find new technology or drugs or whatever the item is.
if there no IP rights existed, this wouldnt be considered stealing. it would just be and everyone could and would do it. and no company would be willing to risk their buisness/employees/money in order to try and research new things. it just wouldnt happen. | 10 |
ELI5: Why does it seem like I have to change my deodorant brand every year or so to avoid body odor? | 1,899 | The smell that emanates from your armpits is largely caused by the bacteria that makes its home there. Deodorants, in addition to smelling pleasant, discourage bacterial growth.
Over time bacteria may grow resistant to some extent if you always use the same type of deodorant. Occasionally switching can help combat that problem.
| 1,465 |
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ELI5: What happens to a fit, pregnant mother's abdominal muscles during and after pregnancy? | 8,284 | They get stretched out, and can separate, causing diastasis recti. Not everyone experiences this condition, and many times the muscles just go back to normal. Your ligaments and joints get loose as well, all caused by certain pregnancy hormones that enable a women's hips to shift during birth. All of this usually goes back to normal in the months after birth. Binding your belly after birth can help your muscles come back together as well, at least anecdotally. Your skin will almost always stay a little looser than before.
FYI, there are many exercises you can do to strengthen your ab muscles after birth (wait a couple months minimum though, to heal) and these are usually not your typical "ab strengthening" exercises/movements. Crunches will not help, and can often make diastasis recti worse. A quick google search will help you find something. | 4,079 |
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ELI5: Why can't we put all our mathematical knowledge into a supercomputer to solve things like the Riemann hypothesis, instead of offering a reward of a million dollars to the human that can? | 40 | At this level of mathematics it's not a matter of the math being too hard, it's that no one has ever thought of doing the math in that way.
If no one has ever thought of doing the math in that way previously, there's no way we could have a supercomputer do it. One way we have computers solve problems like this is that we just give it a set of criteria that suggest "this is the correct answer" then have it just arrange everythign in every possible way.
Not only would this be impossible (even super computers can't arrange all the numbers and functions in math in all ways) to do, we also have no idea what a solution would look like, until someone comes up with it. | 22 |
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[Marvel] What are the odds of a family somewhere sitting alone together and exactly 0 of them getting snapped by Thanos, and how long before they notice half the population is gone? | edit: I never got why people say "wow this blew up" but wow did this blow up
Can't wait to sit down and read all of these great comments. Thanks for the discussion! | 512 | Let's say a family is 4 people. You have 50% chance of getting snapped. For all four people in the family to be spared, the odds are 0.5^4 =6.25%
They would probably notice almost immediately as their social media accounts start blowing up. | 417 |
If we can't get an ought from an is, how else do we get an ought? | For example, if an anti-realist says morals come from our emotions and empathy, and that we ought to follow these emotions and empathy, then isn't this also falling into the is-ought gap? | 17 | The is-ought gap describes the logical problem of not being able to justify a particular conclusion based on given premises.
So one way to approach this question would be to consider the possibility that at least some 'oughts' are basic or implicit rather than being conclusions that are produced _a posteriori_ after a due consideration of facts.
For example, you couldn't have articulated this question without already having implicitly accepted that you ought to drink and eat in order to survive. But this isn't the sort of ought that you arrived at as a logical conclusion; it's an ought that we can recognize as being implicit in your behavior and in your ongoing survival. | 10 |
ELI5: Why is the sound quality of AM radio so much worse than that of FM radio? | I often listen to both music and talk radio while I am in my car, and there is a very large difference in the audio quality between the AM stations that I listen to and the FM stations. It's actually really annoying because the AM stations are all talk radio, so not being able to hear them clearly is rather frustrating. Is it just my car's radio quality, or is there some other explanation? | 4,596 | If you can imagine instead of a radio tower there is a giant lightbulb. This is essentially the same thing electromagnetic energy but instead of being in the radio part of the spectrum it is in the light part of the spectrum.
With the AM (amplitude modulation) lightbulb the signal would be varied by adjusting the brightness of the light. With the FM(frequency modulation) the light would change in color to produce a signal.
If you were trying to see this signal through static, say a bunch of trees it was be much easier to see what color was coming through than how bright the light was.
Edit: missed a word. | 5,748 |
CMV: If an ISP sells your data, you deserve a cut of the profit. | My position is quite simple. My browser history is mine. I made it. If an ISP is going to sell it, then I deserve a portion of the proceeds.
I've had similar debates before and one thing that comes up is: it would only be fractions of a penny. When an ISP sells personal data they don't sell it person by person. They consolidate their data into blocks of hundreds of thousands of individuals and sell that. The data of one person isn't worth much at all (depends on the person I guess) but the data of one of these blocks is. So for me to claw out the value of just my data, may only be pennies and my cut of those pennies might not even be half.
However, I dislike the idea that I am just suppose to accept that someone else gets to sell the product of my work. It's like someone trying to sell the dust from your footsteps. If they're going to do it, I deserve a share of the money. I'm the one doing all the walking.
**EDIT**
I can be very stubborn. I wouldn't be here on the internet bitching about pennies if I were not a silly, bitter person. While my mind has not been changed, all the people participating have valid persuasive criticisms. In responding, many required me to think and re-think my position.
To just stop being an old man yelling at clouds is also compelling.
Thank you for the discussion.
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> *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!* | 2,441 | The browsing history that they sell is not a personal one based on your computer. It is a collective block of information on the wok that their routers do. They are not marking the information you have provided, but merely the actions that their routers are taking while providing that service to you.
In addition, they can just "pay you" by reducing their bill. Then can then also arbitrarily increase their bill by that amount, like they do every so often from inflation. A lack of competition means there is no reason for them to do anything else for you, price-wise. | 364 |
ELI5: Why does gardening without gloves dry your hands so much? What is happening there is it just that dirt is dry and suck moisture or is there anything else involved? | 29 | If the soil is wet, it will dehydrate hands by removing surface oils.
If soil is dry, it will dehydrate hands by absorbing surface oils and moisture.
If soil is abrasive, it will dehydrate hands by scrubbing off surface oils and damaging the skin. | 51 |
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ELI5: Why is Activision acquiring King for ~6 billion dollars? What is the benefit for the company? | 17 | King is a foreign firm so Activision can use money that was mostly sitting in low return bonds (and didn't have many other legal uses without paying a large tax bill).
King makes money, so Activision will gain King's earnings (about $500 million last year).
Activision gets experienced mobile developers and marketers which they can combine with their own very well known gaming assets to hopefully create the next big thing in mobile gaming.
Activision gets access to a massive userbase who are different from their typical customer. | 16 |
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ELI5: How does the golden ratio follow the fibonacci sequence? | 23 | Take two successive numbers of Fibonacci sequence, 13 and 21 for example. 21/13 will be close to golden ratio. Kepler proved that limit of ratio of two infinitely large successive Fibonacci numbers is golden ratio, or lim{n -> inf} F{n+1}/Fn = phi.
EDIT: More general form, as wikipedia says, is lim{n -> inf} F{n+a}/Fn = phi^a, and it leads to phi^{n+1} = phi^n + phi^{n-1}. | 14 |
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ELI5: How languages like Chinese, Japanese and Arabic, with their own writing systems can be written with the latin alphabet? Can latin languages and English be written in their systems? | 15 | We're just making a close approximation of the pronounced syllables. Even though the letters are different, the sounds are mostly the same, so we can just write what the sounds are. If everyone knows what the letters are supposed to represent in another language, and how to pronounce those letters, it becomes easy to romanize.
You absolutely could write out English in the same syllabic style of writing in most other languages. | 28 |
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CMV: I judge people who get gastric bypass bc it's cheating. Overeating should be treated as an emotional addiction instead of going under the knife to remove your organs. | I come across more and more people who go under the knife to get gastric bypass and remove their stomach instead of going to overeaters anonymous to deal with WHY they over eat, exercising & changing their food habits. It seems backwards to me. Those who deal with the emotional issue in why they are overweight while they change their lifestyle and become more active is the answer to weight loss.
I met a woman at work who said she lost 150lbs and I was blown away and so proud of her. I am in the fitness industry so I naturally assumed she changed her habits and that is an incredible story. Later she told a story about how she had two misscarrages in the past and she decided to make a change so her and her husband got weight loss surgery. All of a sudden all her credibility to me is lost. For some reason, to me there's no pride in that.
Idk, just to me, it is absolutely absurd that people are more comfortable going into risky surgery to remove their bodily organs instead of getting to the root of their problem and changing their habits. I don't want to be judgmental but being in the fitness industry, having been to overeaters anonymous myself, having changed my habits ... and watched other overweight people change their life and lose weight by hard work and determination... I just feel judgmental and see weight loss surgery as fixing the symptom not the problem... CMV . I dont like feeling judgmental. | 32 | 1. Gastric bypass doesn't involve removing your stomach.
2. Weight loss isn't a game, it's a health issue. There's no rules, so there's no such thing as "cheating."
3. If obesity is the problem and you lose weight, you've fixed the problem. | 149 |
ELI5: Why aren't any elevators designed so you can press the buttons again to undo the floor selections? | I've always wondered about this; and it was especially annoying when I stayed on the 24th floor of a hotel last month and some jokester from a floor above me decided to press all of the buttons for the way down. Kind of like on Elf when he lights up the entire elevator buttons like a christmas tree. Shouldn't elevators be advanced enough to have this technology?
| 59 | There is an anti nuisance feature that can be enabled on some control equipment that will determine if this very thing occurred, and cancel all car calls. But this has to be requested by the owner. The control equipment has to have this software or ability of course. | 13 |
[Disney’s Tarzan] Why Does He Wear That Little Underwear/Lioncloth Thing? | Wouldn’t he be raised by apes with nudity? | 42 | The funniest explanation is actually the length and size of his... Manhood.
Gorillas have, proportionate to their size, small penises. Tarzan seems to be a freak of nature in comparison.
The second explanation is Tarzan being ashamed of having no fur and trying to hide his groin area in general. | 62 |
ELI5: Why electronics require such specific voltages as 3.3v, 5v or 12v? | Is it just plain standardization? Why such numbers were chosen? How come we never see a household device requiring like 10v?
| 28 | Two different things:
Common batteries come in a multitude of 1.5 volt because a single cell of a alkaline battery provides 1.5 volts when full. This voltage does not change if the battery becomes bigger or smaller, that only changes the duration it can provide this 1.5 volt.
The other, 3.3v, 5v and 12 volt (and you are missing -12 volt) are standardized voltage levels in electronics (and thus computers) and then specially transistors and all inherited technologies like digital chips:
Digital chips (IC's, integrated circuits) specially the TTL series have an "low" or 0 level at between 0.0 and 0.8 volts and a "high" or 1 level between 2 and 5 volts. So the maximum voltage you need there is 5 volts. Bingo, there is your 5.
-12 and +12 volt are (where?) the voltages used for communications, but early logic used +12 because of noise / interference. You needed a huge difference between a 0 and a 1. With the TTL logic later on this wasn't needed so much anymore and you could go back to 5 volts.
Now 3.3 volt: It's part of making chips faster without melting. If you double the number of transistors on the same area and double the frequency, you will need four times the power consumption. That's a lot of heat. If you decrease the voltage for that chip, you will reduce the power consumption and the metal lines on your chip won't melt.
| 30 |
ELI5: How do bonsai trees work? | I've seen the picture of an apple bonsai tree with a single apple on it and I want to know how that happened. | 628 | The tree is limited in how far it can grow, its roots can't spread and its branches are pruned. The tree still matures, it still becomes an adult organism, but it never reaches its adult size, mainly because the lack of roots and leaves stop it from getting enough nutrients from growing that big.
The apple is its offspring, and isn't so limited. The tree still has a tough time getting the resources needed, likely why there was only one apple, but as far as the cells at that branch tip are concerned it's a normal adult tree making a normal apple, which is therefore full sized.
Think of it like an amputee; an amputee who's lost all four limbs is going to have a child with all of its body parts, they won't be smaller than a normal baby and they won't be missing bits. | 734 |
Were there any reasons why homosexuality was so stigmatised in religious texts? | I know throughout history different cultures have had varying attitudes to homosexuality, but the attitudes mostly seem to be negative and often extreme, e.g. scriptures in many religions prescribe the death penalty for homosexuality. Even in societies where homosexuality was allowed, from my understanding they were still seen as less good than heterosexual relations, and often involved a master and slaves rather than consenting people.
I am just wondering, were there any real social reasons why so many religions and societies became so anti-gay, to the point of prescribing the death penalty? For example we know many of the dietary restrictions in religions were originally made for safety or health reasons, to avoid eating foods that may kill you, etc. Was this sort of logic used when societies decided homosexuality was wrong? Did homosexuality bring about dangers to a society, that caused people to stigmatise it so much? | 115 | There is a lot of religious studies scholarship that brings together information from historical and linguistic sources to help understand why the holy texts of many ancient religions, especially the Abrahamic religions, condemned homosexuality. See, for example, Daniel A. Helminiak's What the Bible Really Says about Homosexuality.
One likely aspect is emphasis on procreation, since many non-procreative forms of sex are commonly condemned. Procreation might be particularly important for tribal societies vying for resources with other competing groups. Exclusive male homosexuality might be seen as particularly threatening in patrilineal societies.
Another element is the use of male-on-male rape as a form of asserting domination in some cultures. This could create an association of male homosexuality, at least, with humiliation and/or inhospitality.
As a final example, in some ancient contexts homosexuality was associated with temple prostitution. For cultures without those practices and particularly those in competition with groups with such practices, condemning same-sex sexuality could be an effort to reinforce cultural distinctiveness and ritual purity. | 52 |
Can we predict where the Voyager probes will be in a hundred years (in relation to our Sun)? A thousand? A million? | Considering they are now being influenced by interstellar forces, can we predict where these probes will be long after they've gone silent? | 128 | I work on interplanetary and interstellar navigation solutions and your question is best answered with another question: how accurately do you need to know their position? Even now, we don't know their position to centimetre precision but we certainly know it to a kilometre or two. Interstellar forces play a big role as we've never measured their effects till the voyager probes encountered them. I'll put it to you this way, in another 100 years, you wouldn't be able to fly a ship out of the solar system and look for the probes using modern sensors, the space you'll have to search will be far too vast. | 41 |
[Star Trek Franchise] I'm watching through TNG again. I'm at the episode, "Q Who" and the away team are on the Borg Cube. Why don't Star Fleet away teams wear *any* sort of body armour? What does Star Fleet armour look like? During the Dominion War I don't recall seeing any... | Nog could certainly used some. | 314 | They’re slinging around directed energy weapons with potencies that range from neurological disruption to physical disruption on a personally massive scale, most armor you can effectively fight in would delay your vaporization by a couple fractions of a second. | 177 |
ELI5: How does the idiom "the exception that proves the rule" make any sense? | How can an exception from something prove a rule? Like if i don't blink when i sneeze, how am i in any way proving that people as a rule in fact do blink when they sneeze? | 17 | The expression "the exception that proves the rule" is legal concept (*exceptio probat regulam*), and is often misunderstood. What it actual means is that you can *infer* a law when an *opposite* and *explicit* law is present. The classic example is a sign that says, "No Parking between 8am - 5pm." The explicit law is that the you can't park there during that time period. The implicit law—the law that is not directly mentioned—is that you *can* park there anything *outside* 8am - 5pm. The signs does not say that you can park there, but the principle of *exceptio probat regulam* implies that you can. Similarly, let's say that on the street, one spot has signs that say you cannot park there. This implies that you can park everywhere else on that street. That one spot is the exception, and so the rest of the street is the rule. | 65 |
ELI5: If pre-election polling is mostly done by phone interviews via landline, and the number of landlines is declining among most demographic groups, why are they still fairly accurate? | 114 | It is not accurate that "... poling is mostly done by phone interviews via landline". Actual polling companies call cellphones and have non-phone ways of reaching people. "Polls" limited to landlines are badly disguised political activism. | 51 |
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Does iron still rust when it is molten? | Title | 2,155 | That is actually how you cut ferrous metals with a torch. You heat the metal to a molten state and then blast it with pure oxygen, rapidly oxidizing it. The force of the oxygen jet removes the oxidized product and you are left with a clean cut. | 1,811 |
Can we really see the Milky Way with the naked eye? | I always see [pictures like this](http://i.imgur.com/paoWS.jpg) and I have always wondered if they are real or if it is an exposure thing with the camera?
So can you see it and if so how/when/where?
Thank You
| 70 | Yes. It's not that long ago when everyone saw this regularly.
Now, you need to be away from light sources, like cities, highways, etc. on a clear night. Regular campers have probably seen the Milky Way.
It's impressive. | 93 |
CMV: Because drywall screws exist, there is no reason to buy brass wood screws for basic carpentry. | For basic carpentry (putting up shelves, building a theatrical set, knocking together a picnic table, etc.) phillips-head, coarse-thread drywall screws seem to always be superior to brass "wood" screws. They are sharper, go in faster, don't generally strip, and are plenty strong for most applications. Brass "wood" screws, on the other hand, are blunter, strip like the dickens, and take longer to drive.
I can see that in some cases the color of a drywall screw might be a dealbreaker (black, dull finish), but for structural, basic work (not making fine furniture) I can't figure out why anyone would ever buy a wood screw.
Change my view-- convince me that brass-colored wood screws deserve their shelf space in Lowe's.
_____
> *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!* | 33 | - Dry wall screws are fully threaded and can sometimes split wood, whereas wood screws have much less of a chance to splitting wood.
- Brass is softer than drywall which means it molds better to expanding/contracting wood based on humidity
- Brass is more water resistant and anti-corrosive than drywall
Overall, the most important reason is just the appearance - 95/100 times using drywall is better. But there are scenarios where brass is better, and if these factors are applicable then brass would be used. Examples include sandy/dusty areas, structures subject to frequent weather/water/humidity, etc. | 15 |
[General] Would mermaids breastfeed their young? | 32 | Mermaids are likely full mammal. The tail is probably akin to a dolphin's tail. Therefore, they have eggs, but only internally, and birth their young in a similar fashion to other aquatic mammals. Since they are mammals, they have warm blood, hair(fur) and mammary glands from which they feed their young. | 27 |
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ELI5:Why is GMO Vegetables a "Danger" but Cultured Meat is "Cool" or "Has Potential" | I would like to ask for an explanation of the viewpoint, on why it seems GMO Vegetables are a danger, and threat. While test tube meat seems to be much more positively received , even thought it should or would seem to be the same category as GMO Vegetables?
Is something fundamentally different between the two, to have earn these distinctions? | 39 | Because Monsanto uses GM tech to make themselves a monopoly.
There is nothing more wrong about GMO crops than cultured meat.
There seem to be 2 schools of thought opposing GMO. 1.) Informed people who oppose Monsanto on ethical grounds, 2.) uninformed people who oppose GMO without understanding what it actually is (blowback from #1). | 65 |
How do I practice becoming a better thinker? | Hello everyone
I hope it's appropriate to ask this here since it's not a philosophical question but one about your methods.
I just started studying philosophy and I'd like to improve the way I think; to be more precise, more critical - all in all I'd like to develop a sharper mind.
When googling and youtubing I find that the consensus to improving critical thought is 'writing a lot' and 'reading a lot'. But I just don't really know where to start or what I should be looking for. What should I write? How should I write? What should I read? How should I read?
-How did you become a better thinker?
-Do you have any recomendations or examples for a book or article where you thought "this is some sharp thinking"?
Maybe if I see an example I'd have a better idea for what I'm looking for..
Thanks for reading
-A pupil | 19 | What really helped me become a more critical thinker was honestly reading books on various topics i was interested in, watching lectures on youtube which i think immensely helped as well, and engaging in conversation about the topics I’ve learned to family members and friends. The last point is crucial because you are actively engaging in active recall and it introduces you to perspectives you may have not heard of, all while giving you more perspective and reasoning to aid you in becoming a better thinker. | 14 |
If Hubble is able to take such detailed pictures of the universe, why can't we just point it at Pluto and take some instead of having to send a space probe all the way out there like New Horizons? | It just seems like it would be much easier for Hubble to take a picture of something as close as Pluto | 24 | The average galaxy that you see in Hubble pictures is (very roughly) several trillion times further away from Earth than Pluto, but also anywhere from a thousand-trillion to a million-trillion times larger than Pluto. | 30 |
CMV: There needs to be more transparency regarding the use of artificial intelligence in court sentences | There is little to no regulation to how artificial intelligence can be used in determining sentences for criminals in the US. Currently, some judges have been using algorithms created by 3rd party companies that show criminals “risk level” of committing future crimes to help determine the proper sentence. However, there is little transparency about how these algorithms are made and their potential bias against certain groups. No one gets the see the full algorithm except the company who created it, not even the judge. While I’m not accusing any company of being intentionally biased, these algorithms have the power to exaggerate the current racial bias in the court system. If the full algorithm can be reviewed and be proven not to be unbiased, it would be a lot fairer compared to now, where the lack of transparency is potentially biased against minorities. | 25 | >Currently, some judges have been using algorithms created by 3rd party companies that show criminals “risk level” of committing future crimes to help determine the proper sentence.
That's remarkable. Could you link to some sources explaining what these algorithms are and how they're used? | 12 |
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