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[SW - Darth Maul: Son Of Dathomir] If Dooku had a change of heart and sided with Talzin and Maul, could they have defeated Palpatine together?

Yes. Perhaps not directly, but they could have massively disrupted Palpatine's carefully laid plans. Palpatine's greatest strength (remaining hidden) was also his largest vulnerability at that time. Dooku and Maul together could have robbed Palpatine of the CIS and any underworld resources. This would have forced him to rely on his Republic influence much more strongly and may have disrupted his carefully laid plans, causing a confrontation with the Jedi earlier than planned. This combination of factors could have led to his defeat.

ELI 5: The comic the kid is reading in the movie Watchmen.

I didn't really get it so can someone explain what the ending of the comic meant

The comic tells the story of a man who changes because of what he *thinks* is going on — he *thinks* he's acting heroically in order to save lives. But in reality he's becoming a monster. It's obviously connected to Veidt's actions — possibly because this is how some people will view Veidt (ie Rorshach), or because this is what Veidt is becoming. Depends on how you view Veidt's actions.

What would happen if you dove in a pool while covered with a hydrophobic material?

As the title says. Lets say you get in a skin tight suit or something similar, sprayed yourself with a hydrophobic material (like shown in this video http://www.youtube.com/watch?v=7is6r6zXFDc ) and dove into a swimming pool? Would it make you float? Would you glide through the water?

Likely not much would be different. Let's say you wore a teflon suit, the water would still wet to the teflon suit, as a water-teflon interface is lower energy than a teflon-air interface PLUS a water-air interface. To demonstrate this at home, put a drop of water on a (unheated) teflon cooking pan. The water wets the teflon, despite "beading up" more than it would on a more hydrophilic (metal) pan. A thin layer of entrained air surrounding your teflon suit would be metastable at best, and not persist through the agitation of swimming.

ELI5: if the population was down to just a mere handful of humans left how many couples (man and woman) would it take to repopulate the earth without having any inbreeding in order to get numbers back to where they are today?

There'll always be *some* degree of inbreeding. Even today you might well be distantly related to everyone you meet. The issue is one of genetic viability through variety. I've see people estimate the number of *couples* needed to maintain genetic viability could be as low as 32.

ELI5: Why does my key fob only work for my car?

When I press "unlock" why does it only unlock my car? Why don't other cars react to my key fob? Are they all on different frequencies or what?

the very first ones actually had a keypad on them, and you entered a code to unlock it remotely. these days, that's done on the inside. when you press the button, it sends a unique digital identification code through the radio frequency editor that's in there. you were pretty close.

If I brew coffee with twice as much water but the same amount of grounds, how much more (if any) caffeine will be in the resulting pot?

My intuition says it would contain somewhat more but less than twice as much caffeine. Is that right? Does anyone have a better idea of where in that range you would fall?

It will have almost no effect on the amount of caffeine in the water. Caffeine has a very high solubility in water, especially hot water, so the limiting factor isn't the amount of water used, but the amount of coffee grounds added. Even at room temperature, one cup of coffee with its ~100 mg of caffeine is only around 2% of the saturation level. That's a good thing, because a cup of saturated caffeine solution (5 g of caffeine in 8 oz) is nearly enough to kill you.

Is it possible for an extinct animal to re-evolve into a near-identical form? If so, how does this differ given different scenarios?

Here's some example scenarios that are easy for my small brain to convey, and may be easier for you to understand and answer (if this ends up being too confusing though, just answer the first question in the title): Context: Let's say an animal called the Chilga and an animal called the Nimra share a recent common ancestor called the Kodor. The imaginary Chilga is a blue flightless bird that excels at catching prey using its long legs and thin sharp beak to sprint towards animals and impale them. Questions: The questions I have for each of the following given scenarios is as follows: 1. If the Chilga went extinct, is there a possibility that it could re-evolve from genetically similar animals? 2. If so, is it possible that the Chilga will re-evolve to have identical characteristics to its pre-extinction counterpart? Or will some characteristics be different, such as having green feathers instead of blue, or shorter legs due to an additional joint that allows them to run faster? Scenarios: Scenario 1: The Chilga goes extinct. Both the Nimra and Kodor are still thriving in various locations around the world. Scenario 2: Both the Chilga and the Kodor go extinct. The Nimra is still thriving in various locations around the world. Scenario 3: Both the Chilga and the Nimra go extinct. The Kodor is still thriving in various locations around the world. Scenario 4: All three animals, the Chilga, the Nimra, and the Kodor, go extinct.

Yes, it's possible. There are environmental niches that tend to be filled by animals with certain characteristics, so a repeat of a similar evolutionary path is not unheard of. One interesting example is that marsupials in Australia evolved to have a lot of similar characteristics that mammals have in other parts of the world as a result of filling similar niches and similar selective pressures.

ELI5: What are freckles exactly? How/why do they grow, how/why did evolution cause them, and why do some people have more than others?

The post from two years ago in /r/AskScience didn't help me understand much..

Freckles are just unevenly distrubuted amounts of melanin, the compound that makes your skin color/pigment. They frequently appear on the face of children because of the skin sensitivity of that area, but can appear later in life in areas of high sun exposure, such as the shoulder, back, arms, and legs. As the sun damages the skin, your body will produce melanin to try to protect itself, however, it can be produced unevenly, causes freckles.

ELI5: What do people mean when they say there are two China's?

I briefly read a comment somewhere on reddit where the person said there where to China's. What did he mean by that?

There are two countries which claim to be "China". There's the "Republic of China" (ROC) and the "People's Republic of China" (PRC). The PRC is the one that actually controls what you'd normally call China. It controls that massive territory in mainland Asia, plus the Special Administrative Regions of Macau and Hong Kong. The ROC only controls Taiwan and a few surrounding islands. Most people would probably just call this country Taiwan rather than China, but officially they claim to be the legitimate government of mainland China too. This all happened because before and after WW2 there was a civil war between the Communists and the ruling Nationalists. The Communists managed to take over the mainland and declare it the PRC, and the Nationalists retreated to Taiwan. After a while most of the rest of the world decided to accept the PRC as the legitimate government of China, and on paper don't recognise Taiwan as a separate country.

Can economies be expected to grow overall, forever?

So I know there are periods of growth and a recession every 7 to 10 years give or take. But my question applies to the longer time frame. Can modern economies continue to grow at the rates we've seen forever, or will increases eventually start to taper off? If they're expected to taper off, what implications does this have for say retirement plans because they rely on long term economic growth? I know this would probably be like centuries down the line but it's just an idea I thought was interesting.

>Can modern economies continue to grow at the rates we've seen forever, or will increases eventually start to taper off? I think the answer to this can be boiled down into one simple question: do you think our technology can always keep improving? So much of growth literature (and macro literature overall) is focused on the technology level and how exactly it grows. Seminal work from Lucas and Romer in the 80s and 90s is worth taking a look at. But at any rate, let's imagine a super simple scenario where the production in the economy is determined solely by y = A K^x N^(1-x), where K is the capital stock and N is the amount of work put into it. So obviously, there will be an upper limit on N, determined by the number of people who can physically work. Perhaps we even say that there's an upper limit on K, or we're only really interested in a "steady-state" K (in other words, changes in growth rates are being driven by capital stock). Then it just boils down to: how does A change over time? If you think that we can always keep making that bigger (aka make more stuff with less input), then sure, we can always keep growing. If you somehow think that's limited, then real growth could taper off.

[40K: Space Marine] If completed, would the doomsday device have made a difference?

In the game the inquisition is working on a doomsday device that seems to be capable of instantly killing all Orks on a planet instantaneously. The project never comes to fruition to due to the Okrk invasion, but I can't help but wonder: if the project had been completed and worked as intended, would it have made a difference in the endless threats besieging the Imperium?

Are you kidding?! Orks are probably the single largest threat facing the Imperium, purely because of how insanely numerous they are and how tough it is to eradicate them. Thousands of worlds and trillions of lives have been lost to the green menace and it will only get worse. The ability to essentially flip a switch and annihilate the entire ork presence on a planet would be a total game changer. What would take millions of IG several years to accomplish (and not permanently, due to ork spores) can be done overnight without any damage to the planetary infrastructure. The amount of manpower and resources that would be freed up to face other threats would be staggering, and could very likely tilt the balance of power firmly in the Imperium's favor.

Does the body store protein for muscle building, like it stores energy as fat for later use? If so, how does it do this?

Amino acids are 'tied up' in protein structures in the body. It should be noted that proteins in the body refer to a wide variety of different biological structures with varying functions - not just components muscle cells themselves. Proteins contribute as structural components, biocatalysts (enzymes), antibodies, hormones, lubricants, carriers etc. All of these may contribute to skeletal muscle protein synthesis in some way. The basic functions of proteins can be divided into: growth (pr synthesis), maintenance (pr turnover), regulation (hormones, acid/base balance, enzymes), energy (contribute to glycogenic or ketogenic processes). There are basically three fates for an AA in the body: 1. protein synthesis 2. as metabolic intermediaries for gluconeogenesis or fatty acid synthesis 3. carbon skeletons used in energy production They can provide a significant percentage of energy requirements - sometimes as high as 50% in high protein diets. Also the BCAAs can be directly used by skeletal muscle as an energy source, and glutamine and alanine by the digestive tract. There is a small free amino acid pool located in the intra/extracellular spaces that is not bound up in protein structures. This contributes to around 0.5-1% of the total amino acids in the body and plays a large role in the balance of muscle protein. It is thus in constant flux and can vary significantly. For a net increase in protein synthesis in the muscle, you have to have: 1. increase in rate of synthesis 2. decrease in rate of breakdown or 3. both To rephrase this: Your protein balance is a function of input versus output and this is in a constant state of flux. Muscle tissue is highly plastic and can definitely function as a 'reserve' within the body. Less active muscles actually see more use as a supply of AAs when needed. For example, the amount of leucine oxidised during training can be as much as 25x the amount available in the free AA pool, so endogenous breakdown can be a major source of AAs. there are at least four ways cell protein concentration could change: 1. increased transcription 2. increased translation 3. decreased rate of mRNA degradation 4. decreased rate of degradation of the protein So the rate of protein synthesis in skeletal muscle taking place during or after exercise depends to a large extent on having a complete complement of precursor AAs. It can also be affected by the availability and efficiency of various enzymes, tRNA, ATP etc. Long story short, the amount of intracellular AAs can be an indicator of the level of protein synthesis in muscle, but there is no particular 'storage' capability equivalent to glycogen or fat. Amino acids are either used in metabolism or to form protein structures with a function beyond simple storage. A very small amount is kept as a free AA pool.

[Legend of Korra] what is the fuel sauce used to power vehicles is it petrol/gas as the vehicles have internal combustion engines ?

It almost certainly is gas/petrol. One of the comics that follow up the original series (*North and South*) has oil exploration in the South Pole by a Northern Water Tribe corporation as a subplot. This indicates that gasoline is a thing in the Avatar world, and is presumably used in vehicles.

ELI5: Why do teeth, unlike other parts of the body, not heal properly?

Teeth don't have cells. Healing takes place when cells divide to replace cells that were lost. Your teeth were grown inside your body and then pushed out. Our DNA is only programmed to do this with 2 sets.

[ST] If Scotty invented Warp Speed Transportation later in his life, and this is communicated back to a younger him, why in the primary universe, where it was only old Scotty aware, do we not see Warp Beaming in VOY and DS9? Or the TNG Movies?

Probably because it happened after the TNG movies. He was found in suspended animation in TNG. Bones was 137 when the Enterprise D launched. Odds are Scotty would still be alive as well during the Hobus crisis.

ELI5: How does a Roth IRA work?

My brother's been telling me about using a Roth IRA and using mutual funds to become a millionaire. Someone wanna help explain what a Roth IRA is and how it works?

Okay, so first let's talk about what a *security* is. A security is, in the most generic sense, a thing which you buy today for some price $X, and which you sell in the future for some price $Y, with the goal being that Y should be greater than X. It's a simple idea: You buy low, and then you sell high, and you end up making money on the deal. One type of security is a *share in a mutual fund.* You know how you can buy shares of stock which give you an ownership stake in a company? Like imagine you own a company that makes widgets. You can divide the ownership of that company up into pieces, called shares, and then give some to yourself and sell the rest. These shares are securities, in the sense that we defined above: They can be bought, held on to for a time, then sold at a different, and ideally higher, price than what was originally paid for them, because in the time between buying and selling the shares became more valuable. A mutual fund works *kind of* like that. It's basically a pool of money which is used to buy securities, but rather than each member of the pool directly owning some of the securities, the securities are owned by the *fund itself*, and the members of the pool own *shares in the fund.* You might buy a share of a mutual fund which owns shares in the widget company we described above, but then sells those shares and uses the money to buy shares in a different company, one that makes gadgets. When those shares in the gadget company have gained in value a bit, those shares are sold and the money's used to buy shares in yet another company, this one making thingamagigs. And so on, and so on … but you, as a shareholder in the fund, don't need to worry about any of that. All you need to know is that the shares you own in the fund as a whole are accruing value over time through the wise buying and selling of securities on the part of the fund manager, the person responsible for managing the fund's portfolio and increasing its value over time. Of course, the basic rule of buying and selling assets applies to mutual funds as well: You are not guaranteed to make money. In fact, you aren't even guaranteed to *keep* the money you start out with. It's possible for mutual funds to lose value over time, meaning if you put $10,000 into one right now, a year from now your share of the fund might only be worth $9,000. So why would you put money into a mutual fund rather than just putting it into an interest-bearing deposit account, or buying bonds with it? Because an interest-bearing deposit account or bond investment might, over a year, turn your $10,000 into $10,300 if you get a good rate … while a mutual fund *has a chance* of turning your $10,000 into $12,000 in the same time. There's a chance for bigger returns, balanced by a chance that you might lose value over time. (This is pretty rare, though. Most mutual funds are well-managed, and give you returns that are *at least* somewhat better than what you could get from risk-free investing over the same period of time.) Now the question becomes, how do you go about buying shares in a mutual fund? Well, the most obvious way is just to walk into the office of some mutual fund someplace and write them a check. But when you do this, you need to know two things. First, the money you use to buy the shares of that fund has *already been taxed.* If you earned $30,000 last year and paid $10,000 of it in taxes, the $20,000 you have left is all you have to buy shares of the fund with. The other thing to know is that in the future, when you cash out of the mutual fund, *you're going to be taxed again* on the *profits* you made from your investment. The rate at which those profits are taxed depends on how long you stayed in the fund and how much you made when you got out, but the point is the government is going to take a cut. The way around this is to structure your investment as a Roth IRA. IRA stands for "individual retirement account", and a Roth IRA is a type of IRA (named for the guy in the Senate who sponsored the law that created it). The virtue of structuring your investment as a Roth IRA is that if you follow certain rules, you can get *out* of having to pay taxes on the profit the investment pays you. These rules are pretty complicated, and involve contribution limits — a limit to how much you can put into your investment every year — and seasoning times — how long you have to leave the money in the investment before you can take it out. But as long as you work within those rules, a Roth IRA backed by a well-managed mutual fund can be a really good way to store your money, protect its value against inflation (by getting a return on your investment that's equal to the rate of inflation), and make a decent profit for your trouble.

[Harry Potter] Could “The Doubling Charm” be used on a hamburger? If so, would that hamburger have the same nutritional value as the original (if eaten quickly enough)

From what I understand, The Doubling Charm creates a perfect replica of whatever it’s cast on; however, over time, the copy breaks itself down and it’ll lose value... while it does say it can’t copy metaphysical or fundamental entities, it doesn’t exclude organic matter in its description.

The relevant passage from Deathly Hallows: Hermione: "Your mother can’t produce food out of thin air, no one can. Food is the first of the five Principal Exceptions to Gamp’s Law of Elemental Transfigura—" Ron: "Oh, speak English, can’t you?" Hermione: "It’s impossible to make good food out of nothing! You can Summon it if you know where it is, you can transform it, you can increase the quantity if you’ve already got some..." So, while it's not clear if the Doubling Charm specifically works, there should be spells that can duplicate food.

[Van Helsing 2004] Dracula's "clothes" seem to transform with him when he turns into the huge bat creature, does it mean those aren't his clothes at all, and are just skin made to look like it?

http://stream1.gifsoup.com/view4/1407934/dracula-van-helsing-o.gif Sorry for the quality. So, does it mean dracula can't wear something else? Is he technically naked the whole film?

Dracula’s transformation isn’t a purely physical thing. It’s a spiritual/magical transformation. As such it doesn’t matter what he wears. He could be naked or fully armored, he’ll transform without hindrance

CMV: Free speech and the right to express controversial opinions must be protected (and should be respected) in a free and open society.

I know this is a touchy subject right now, but it's one I've been struggling with recently as a result. Let me start by fully acknowledging that freedom of speech does not equate freedom from consequences. 99% of the time, I fully stand behind that philosophy. That said, I believe that "cancel culture", doxxing, and the current intolerance amongst some on the left of any free speech deemed to be hateful, ignorant, or highly controversial is, at it's core, unproductive and antithetical to the very democratic ideals that allowed many of those movements arise and build consensus in the first place. What is deemed an appropriate or "acceptable" opinion has always been defined by the culture and zeitgeist of the times, but opposition to such opinions should revolve around public debate and political and economic disengagement (i.e. boycotts, voting, removal of media platforms, etc). What it should not entail is a rage-fueled vendetta against someone with the explicit or implicit intent of inflicting suffering and lasting, personal harm (like, for example, having the private details of them and their family blasted across the internet). This creates a culture where only some people get to decide what is an acceptable opinion and I worry that this a slippery slope. I'll be the first to admit that America is *far* from perfect, but what has often separated us from other countries is our shared belief in protected free speech and the right to express it. And there will always be consequences to such speech, but those consequences should involve resistance to the content of the speech and the platforms that support it, not some spite-fueled attempt to ruin another person's life (deplorable as that person may be). This only fuels a devolving tit for tat that endangers (what I feel) are the very tenets of a free and open society. I would love hear your thoughts. For the record, I'm a progressive and am very left-leaning myself. I believe we need systemic change in America and that speaking truth to power is how we get there. I just worry that the rhetoric and backlash on the left right now towards those who disagree is endangering some of the very values that progressive, liberal democracy stands for. If my right to free speech is protected and celebrated, then so should yours. \*EDIT: typo

The thing I've noticed with these topics is that if you ask 5 people what "cancel culture" is, you'll get six different answers. It's hard to have a discussion without knowing exactly what you mean. For instance: >but opposition to such opinions should revolve around public debate and political and economic disengagement (i.e. boycotts, voting, removal of media platforms, etc). For some people, this is what cancel culture is: refusing to engage or associate with a person, refusing to buy give money to companies who do, pushing to deplatform them, etc.

Has the popularity of reusable bags and cups decreased the consumption of plastic/paper bags and cups? Are we actually saving fuel and resources?

I feel like everywhere I go I see reusable grocery bags and plastic tumblers and bottles. Has the production of all these things meant to be reusuable made any dent in the use of disposable products? Is there any net energy or resources savings? **Edit to add:** I support the use of these things, and felt compelled to note that because there are some people ITT that seem to think this question dismisses the use of them. I am just wondering about the actual economics and enviromental impact of people constantly buying and re-buying reusable bags and bottles.

Bonus question: At work, they took away the (recycled paper) coffee cups and made everybody use their own coffee mugs. This has resulted in everybody washing their mugs in the sink and using tons of paper towels. Which is worse?

ELI5: Our bodies have adapted to make sugary things taste good since they provide energy. Why hasn't the same thing developed with healthy items like vegetables?

Because vegetables don't provide as much energy as sugars. They are only considered healthy in a modern context of an abundance of food. If you go back several thousand years (an eyeblink in evolutionary terms) finding enough food was a real problem that occupied most of your time. High energy foods like sugary fruits and fatty meats were *way* better than vegetables.

What is an observation in quantum mechanics?

From what I understand, an observation causes the wavefunction of a particle to collapse (forgetting this year's Nobel for a minute). This collapse is due to the interaction between the measurement device and the particle. As a simplified example, to observe an electron in some way a photon can be scattered off of it. The interaction between the two causes the wavefunction to collapse. Now if an electron is traveling through space in an area near an energy source so that the photon density in the space surrounding the electron is very high, does that mean the electron will constantly exist in some sort of collapsed state? How exactly does this work? We don't really cover what exactly constitutes an observation in class, but the professor almost makes it seem like there is a human element attached to the process -- as though even though the electron would be constantly colliding with photons its wavefunction would evolve as though the photons are not there unless a human observes the interaction? Can someone please explain this to me?

Observation does **not** require a human element. In QM an observation can be thought of as any interaction between two quantum systems which entangles them. When this happens, if you try to look at the state of one system alone, you get a classically mixed state (which is basically what people mean when they say the wavefunction has collapsed).

Why do fabrics become more resistant to tearing when wet, while other materials, like paper, become more prone to it.

Simply put because the wetness softens the fibers. In a woven fabric, the fibers are basically going the entire width of the item in one strand. So when they become softer, they tend to stretch or slide past each other, and they still need the same amount of force applied to break each fiber, but it is harder to apply that force to each fiber. In paper, they aren't woven. They are just laid down in the sheet, pressed and dried. So when the fibers soften, and slide past each other easier, it is that much easier to pull one fiber completely free of its neighbors. Edit for clarity: In a fabric, they are purposefully woven so that the fibers don't pull free of each other easily, the hems and seams prevent fraying. In a paper product, they aren't. So in a fabric you have to break every fiber in the ripped area, in a paper you just have to pull the fibers away from each other.

Can we forget what a color looks like?

Say a normal person who has lived with colors their whole life, were put into a black box, without any other color. Would they eventually forget what colors looked like, why/why not?

Ever heard of the colour Taupe? Look it up now, then try to remember it again in a week. I can never remember if it's a shade of yellowish-green or magenta. EDIT: Turns out it's neither, it's beige...

ELI5: What happened at the New York Stock Exchage today and what it affects

What exactly happened at the New York Stock Exchange today, and how does it affect anything?

To put it simply the computer system that runs the NYSE crashed and it took about 3 hours to get it back up. It's believed to be an internal technical issue that has now been resolved. Strangely enough though, Anonymous, the hacking group, tweeted something about it yesterday, but the media is reporting that there was no malicious involvement. Will this affect anything? Not really. There are 11 other stock exchanges and lots of the trades from today were just routed through the NASDAQ.

ELI5: Why is harvesting rain water illegal.

Been hearing for this for a while, why is it illegal?

Okay typical harvesting of rainwater usually isn't illegal. Whats illegal is trapping large amounts of water on your land. So you cant go and build an artificial lake to catch all the rain on your property. This is because in many places farms depend on the water that would have run off your property into streams. Simple rain barrels arent illegal, giant water storage like diverting streams etc is.

ELI5: How do fortune tellers know what to say to you?

I don't believe in fortune tellers but i'm guessing there is some trick in order to guess information about people in order to "tell their fortune/horoscope"

Fortune tellers do what's called cold reading, picking up on little nicks and things that you physically show. They are also great at reading on your vulnerabilities such as emotions. They then attempt to predict, based on information that you have provided, try to create a crazy, but understandable fortune that can actually occur, such as the death of a loved one or you going bankrupt, not that dragons appear or Thor comes down from the heavens. If that person is really vulnerable they'll accept that information and then believe that's going to happen. Placebo effect takes place and they start acting like it has been foretold to happen. Then it actually happens because of the person's actions and they believe that the fortune teller was right all along. It's all bullshit and they are just really good manipulators and they interpret information really well.

CMV: Limiting business hours is not a reliable way to limit the number of customers and may actually be detrimental

I've seen a lot of businesses recently shifting their hours to try to limit the number of people coming to their store. While this may be effective in shopping malls, where a lot of people wander store to store just to shop, I do not think this is effective for the huge majority of stores, and may even have negative consequences. If I need to go to the store (for necessities like food), I'm going to make an effort to go to the store whether they've limited their hours or not. All that limiting store hours does is take the number of people who were going to come to the store throughout the day and put them into a shorter timespan. This also has the negative effect of crowding people closer together in the store. Rather than having the same number of people spread throughout the day, you have put them closer together and perhaps more at risk. I fail to see a benefit to this policy, at least for a majority of stores.

So, the counter to this is that some stores are limiting hours to enable their staff to clean more than usual. In other cases - 24 hours stores have dropped an entire shift of workers. This is a group of people less exposed because that entire shift is not working. While you might be concentrating the number of people at once, if it is still below guidelines on average, cleaning surfaces may be a better option than spreading those people out.

[BTTF2] Why is Biff the carwasher so much nicer than Biff the grandfather in 2015?

What happened that caused him to essentially revert from looking for advice on matchbooks to bullying?

1985 Biff was *terrified* of the McFly family. He has a bad reputation in Hill Valley because of the attempted rape back in 1955. While they couldn't prove anything, nobody would hire him. Seeing an opportunity to get back at him, George McFly offered Biff a job as a carwasher and general servant. Biff knows that if he steps out of line, George will fire him. As the years go by and people slowly forgot about Biff's reputation, he began to lose his fear of George. Additionally, the sight of his grandson developing into a mirror image of himself in 1955 inspired Biff to relapse into his old habits.

[Star Wars]Why is the battle of Yavin used as the dating point in the galaxy?

Sure it was a defeat for the Empire but it wasn't the end of it, but wouldn't the battle of Endor be a better candidate?

It was more for the significance of the battle. It marks the destruction of the first Death Star, an unbelievably huge victory for the rebels. Not just in the destructive power of the Death Star's weaponry, but also the millions of Imperials on board, all the resources it held, thousands of ships, and all the time it took to build (20-some years?). It's also a major boost in confidence, moral, and credibility for the rebellion as it's their first major victory that shows that the Empire isn't all-powerful and can be taken down. After the Battle of Yavin, the rebellion started gaining support from thousands of systems that were originally neutral or not-pro-rebellion in the war.

[Left 4 Dead 2] Why was it necessary to blow up the gas truck with a rocket, instead of going around it?

Could a pipe bomb or Molotov not have done the job either?

Well, they figured crazy man with guns plus relatively easy task to retrieve cola, a rocket would have gotten the job done faster, and doing the favor would have decreased the risk of being shot by him. Also, it was payment for the guns they took from his store.

ELI5: Why does adding one methyl group to Adderall change it from being a common prescription medication to an extremely hard drug?

Why does adding one oxygen to water change it from being refreshing to a corrosive nightmare? Even seemingly minor alterations to a chemical structure can radically alter the way it interacts with itself and other molecules. In this particular case, the methyl group in *meth*amphetamine is altering the electron structure around the adjacent nitrogen center, which significantly accelerates its reactivity.

ELI5: Why gaming companies want to remove gameplay videos and "let's-plays" from YouTube?

That's not what the current issue is about, it's about monetizing. People can make money from their videos based on the number of hits. The new content ID system scans whole videos for even a tiny fragment of copyrighted content and tries to give all monetization of the video to the people it thinks own the copyright, as well as allowing nonsense fraudulent claims. Many game studios have come out and said they're fine with people using their content in stuff like LetsPlay videos or video reviews of their games. The only one who's explicitly said they'll attempt to claim copyright on every video they can is Nintendo. No studio actually wants to have the videos taken down, except a couple of very specific instances where a development company has put out an awful game, then tried to copyright-claim bad reviews of it off YouTube whilst letting positive reviews remain.

ELI5: Why are snowflakes symmetrical?

How does one side of the snowflake know what what the other side looks like? How do they grow six identical segments? Shouldn't the shape of each segment be random?

The formation of ice crystals is dependent on the precise atmospheric conditions. Because each arm is experiencing the same atmospheric conditions, each arm forms the same way. This is also why no two snowflakes are alike: each one follows a different path to the ground and experiences different minute fluctuations in temperature, humidity and airflow, all of which impact the crystal formation.

[Star Wars] If Anakin had never been discovered, would he have consciously figured out some of his abilities during his lifetime?

Maybe a little. Most force-sensitive people can live their whole lives without realizing that there's something more to them than uncanny luck or skill. If at some point Anakin would get a reason to try and delve deeper, he might have developed some low-key abilities, like weak telekinesis or enhanced senses or reflexes, but it rarely goes beyond that.

ELI5: Why don't we trigger our gag reflex when we swallow food, but we do if we put our finger down our throat?

Our body doesn't like something being both down our throat and out of our mouth at the same time as it will choke you. Same goes for toothbrushes. You mouth is very aware of the size and shape of things you shove it it.

[marvel/dc] what would happen if the Hulk got a red Lantern ring?

I know it's different universes blah blah blah, but any ideas on this?

He'd be crazy powerful. Possibly infinitely-so. Hulk already gets more powerful as he gets angrier, that would also mean his ring gets more powerful. He might not actually get the acid-blood thing either, since his own regeneration may counter it. However, it would still probably cause him pain, further feeding his rage.

[The Dark Knight] What would the Joker have done when "Gotham was his" following the ferry debacle? What was next?

Nothing. Joker had no "next plan". His entire plan was to show that the entire human race was irredeemable, that humans were one bad day away from throwing off civilization and descend into chaos. Had the Ferries blown up, gothamites would have felt immense guilt and some would then spiral into insanity, creating more Joker-style crimes across the country. Thus proving that life is the cruelest joke played on us all.

Ok so ios14 is coming soon, how long can we keep using iphone6 running on ios12?

Your phone will continue to perform just fine for normal tasks like calling, texting and browsing the internet. However, app manufacturers may soon end support for iOS 12 over the next year or two, meaning that some apps may cease to function as they require iOS 13 or later, which is not supported by your device. I hope this helps a little more than the arseholes that have responded already.

ELI5: why do we "hide under the covers" when we feel endangered. Why do we feel like it makes us Safer?

I searched first, but none of the answers satisfied me.

We are taught this at a subconscious level throughout our childhood. You are put to bed by your parents, given special attention in the form of stories or goodnight kisses, and told everything is fine. Repeats this every single night of your young childhood and suddenly there is a very strong psychological reason why you think under the covers feels safer.

[Star Wars] How does the Deathstar move?

Are there like some thrusters hidden underneath it that we just never see in the movies?

The Death Star had giant ion engines which only failed to strike terror into its enemies because of the overwhelming scale of the rest of the construct. These ion engines provided thrust through space, such as maneuvering around Yavin's gravity well or orbital station-keeping at Endor. The Death Star also had several vast and interlinked hyperdrive generators (backed by formidable computing power) which allowed it to move rapidly around the galaxy's Outer Rim. Both of these systems, and the main superlaser, were powered by a hypermatter reactor with several times the power of a captive star.

CMV: Circumcision is straight up genital mutilation, no different than female genital mutilation, and should be banned by law.

The foreskin is a necessary and natural part of the human body. It contains 80% of the nerve endings in the penis. It is the main sexual area of the penis, the primary erogenous zone. Cutting off the foreskin is no different than cutting of the clitoris. Yes, you can still have sex without a clitoris, but it's nowhere near as pleasurable or satisfying. It was generally practiced by anti-sex bigots to prevent masturbation, usually with a religious bent, as is true with most harmful anti-sex practices. It does nothing to prevent disease. Cultural reasons are only valid is the individual is a legal adult making this decision for their own personal desires, like any genital piercing or body modification. Fear of being shunned, as is also seen in cultures that practice adult female circumcision, is the result of emotional abuse. Mutilating your children's genitals should be considered child abuse, it should be illegal, and offenders should not only go to jail but also lose custody of their children. EDIT: To clarify, I mean that circumcision should be considered LEGALLY no different the female genital mutilation. It is already illegal to force FGM onto infants and children, and would not be performed by a doctor unless there was a valid medical need. To further clarify, I don't mean that all parents who are solely motivated, but the cultural factors leading to the practice. Furthermore, I have now seen evidence that it may be effective in helping reduce the chance the risk of HIV infection, but that would not be a concern for a child and is only important if you do not live in the developed world. The 80% of the nerves statement is not easy to verify, but the idea that the foreskin is the most sensitive area on the penis still stands.

So, accepting that the whole “80% of the nerve endings” canard is one that you can’t source and have no reason to believe, we’re left with two questions: (1). What is the actual harm? Well, that’s a tough one, since we can’t actually have someone who was circumcised as an infant compare their pleasure (or ease of pleasure, or total enjoyment) to themselves as an uncircumcised person. And without the “foreskin = clitoris” equivocation (which you admit you can’t source), there is no reason to believe that sex without foreskin is significantly less pleasurable or satisfying. Nor would you be able to find unbiased sources for any of the other claimed mechanisms by which removal of the foreskin would reduce pleasure or satisfaction. It’s all speculation which begins with the premise that removal of the foreskin *must* make sex less enjoyable, so why, rather than proof that it *does*. (2). What are the verifiable benefits? Let’s go back to your CMV: >It was generally practiced by anti-sex bigots to prevent masturbation, usually with a religious bent, as is trued with most harmful anti-sex practices. It does nothing to prevent disease This is a weird bit of equivocation. You first posit that circumcision is “no different” from removal of the clitoris, and then refer to the lack of medical benefits from removal of the clitoris. You speak not at all to the medical benefits of circumcision. So, I’d suggest you read the American Academy of Pediatricians’ most recent guidance on the subject, in which they concluded that the medical benefits outweighed the harm and should be left to individual parents to decide. But the more insidious argument you make is that because a practice was done for stupid reasons in the past, it is invalidated as a medical practice even if we discover it was a good idea done for the wrong reasons. Trepanning was done way, way, back for the purpose of letting evil spirits leave someone’s head. Now we call it a craniotomy and know it should be done to relieve intercranial pressure. We once bled people to reduce the bad humours in their body, and now know it’s a valid treatment for hemochromatosis and polycythemia. We knew we should chew on willow bark because the spirit of the tree would heal you before we knew it was actually acetylsalicylic acid. So let’s say circumcision *was* done to prevent masturbation in the bad old days of Kellog being crazy. Why would that invalidate real and statistically significant benefits today? To put it another way: why do you think you have a better grasp on whether the benefits exceed the cost than actual doctors?

Why are viruses so much harder to kill than bacteria?

With the rise of CoVid-19 there are tons of news reports about the fact there are no medications for this virus. Obviously we have tons of antibiotics, but why are antivirals so much harder to develop?

Antibiotics kill bacteria by interfering with the bacteria’s metabolism. They usually sabotage the creation of new bacterial cell wall resulting in the cells to burst, or they mimic nutrients that the bacteria gobble up but ultimately cannot use, so they starve. Viruses are not bacteria. They barely fit the definition for ‘alive’ and lack any sort of metabolisim that we can exploit. Put a virus in front of you and it will just sit there, completely inactive. A virus particle only consists of a little bit of genetic information (DNA or RNA) and a protein hull or sheath. That’s it. Viruses only activate by coming into contact with a living host cell. Their genetic information then enters the cell and reprograms it so that it now produces many more virus particles. And that’s the difficulty. Since they don’t have their own, discrete metabolism there is next to nothing that can be sabotaged that doesn’t also affect the host. Basically, if we want to find drugs against viruses we have to find one for each virus type or family separately (and hope that is doesn’t mutate and then drug becomes useless). That is a VERY long process and we haven’t had much luck yet. HIV drugs are now around that cannot remove the virus, but can force the virus into a sort of inactive state as long as the drugs are taken. HIV positive patients now have a near normal life expectancy if they adhere to the therapy. Tamiflu was created for influenza viruses. The idea is that it inhibits an enzyme that new virus particles need to detach from their host cell, so now thy can’t infect new cells. Nice in theory and some countries stockpiled it for severe outbreaks but it turns out that the drug is next to useless. Acyclovir is used against Herpes (zoster) infections quite effectively. That’s it. Among the thousands of viruses that we have and that affect us, that’s the best we can do at the moment.

ELI5: The difference between one 30% alcohol beverage and three 10% alcohol beverages

Further info, why is one 100% alcoholic beverage posionous but 10 10% beverages fine?

Assuming the volume of all drinks are the same, the difference is the amount of non-alcohol you consume between them. If you drank three ten oz. drinks with 10% ABV each, you'd have consumed 3 oz. of alcohol but 27 oz. of non alcohol. If you drank one 10 oz. drink with 30% ABV, you'd still consume 3 oz. of alcohol but only 7 oz. of non-alcohol. Drinking three drinks would probably take you longer, too.

Why is there a limit to how big wooden boats can be?

I recently read that boats made solely of wood have an upper limit in dimensions if they are to float. While I instinctively thought that this made sense, I could not quite come up with concrete reasons for it. Could anyone explain?

A boat is structurally very similar to a bridge (or an airplane wing). At its worst case (e.g. in very heavy seas) it will be supported by the ends, or entirely in the center with one/both ends cantilevered. For a given length, mass, etc, a certain amount of strength is required to meet the structural needs of a boat hull. All materials have some limit in strength that creates an upwards boundary for the maximum size structure practical with that material. Wood's limit For boats is a few hundred feet. Steel can go a few thousand. Of course you can play tricks (multiple articulated hulls) to create a boat that is bigger than the "limit".

If I were able to watch an object enter a black hole, would the object going into black hole eventually come to a stop from my point of view or would it disappear as it passed the event horizon?

Given that time runs slower relative to me, shouldn’t the object passing through the event horizon come to a stop eventually through my eyes?

It will technically never stop, because it won't ever reach the event horizon from your perspective. It will continue to slow down and light coming from it will continue to get red shifted further and further. It will be invisible to human eyes pretty quickly. You'd need some other kind of detector to continue to observe it.

If I am a moral realist and I reject the "natural law theory", then what non-consequentialist theory can I subscribe to? Is there any other deontological theory as robust as natural law theory?

In his book "Disordered Actions: A Moral Analysis of Lying and Homosexual Activity", John Skalko argues that - " Just fifteen years ago, the common non-religious consensus was that homosexual acts were immoral. Within one decade, however, this consensus waned. The secular majority no longer held, as they previously did, that such actions are morally bad. What explains this sudden change? One explanation is that many conservatives lacked adequate philosophical tools to explain the foundations of the earlier historical consensus. Another is that modern research has shown that there never existed any solid philosophical grounds for calling such actions immoral in the first place. This book questions the latter narrative; for prior to this book no exhaustive historical treatment of philosophical thought on the moral question of homosexual acts existed. Both liberals and conservatives failed to research adequately the long history of thought on this issue. The current author not only argues that the earlier non-religious philosophical consensus has largely been ignored, but that the proliferation of arguments in favor of acting on homosexual inclinations reveal a strong desire to justify what isn't possible to justify morally. **The non-religious arguments of the great philosopher Thomas Aquinas are then examined; they reveal that his reasoning can soundly show that acting on homosexual inclinations is morally wrong,** and also that the same argument rightly entails that every untruthful assertive speech act is morally problematic. If conservatives wish to be consistent, they ought to reject lying too. And if liberals expect conservatives to believe that what they preach is true, then they ought to stand with Aquinas and reject all lying as intrinsically evil. " ​ Now, most natural law theorists like Feser, Skalko, Hsiao and others suggest that the natural law theory is robust and has great explanatory power. Adapting natural law theory is the correct or rational thing to do. What are some arguments against these theories? Also, if I reject natural law theory, then what (non-consequentialist) theory can I subscribe to without sacrificing moral realism? I read that Kantian theory is another good theory but that theory also seems to suggest that homosexual sex, masturbation, are all wrong acts. Is there any other moral realist, rights based deontology theory that is available to people who reject that masturbation and/or consensual homosexual are wrong and/or immoral and/or irrational?

>I read that Kantian theory is another good theory but that theory also seems to suggest that homosexual sex, masturbation, are all wrong acts. I mean Kant thought this, but contemporary Kantians do not.

[DC/Batman]What are Bruce Wayne's political belief?

With the upcoming election I have been meaning to question whether Bruce Wayne is either a liberal,consecutive or any other political belief

I think it's worth considering the Wayne family's background- they were indisputably wealthy, but not in the same way that a self made man like Lex Luthor is- with his LexCorp and his battlesuits and so on. The Waynes, by comparison, seem to have been what you might call "old money"- it had a source at one point, but it's been rolled over so many times in the form of investments that they were 'rich by being rich' the way some people are 'famous for being famous'. Traditionally, these families (whether they're the old families of Virginia, the Brahmins of Boston, or the (as the nouveau riche used to call them) "lockjaw" families of New York, just north of Gotham) got into politics as a sort of public service out of *noblesse oblige*. This can include conservatives and liberals alike, and includes both direct participation (running for office, like a Roosevelt) and sitting on boards of powerful organizations. Bruce Wayne is, understandably given his childhood, somehow a bit reclusive and a bit of a party-boy. Wayne Foundation reps sit on boards for various charities and civic institutions, acting on his behalf. This is a very old-school thing, and exists outside of party politics. It actually isn't unheard of for big-name donors to give generously to *both* candidates in a race, so they have the ear of the winner no matter what. (That is, thinking long-term.) That said, he stays relatively clear of Gotham's notoriously corrupt Mayoral politics. He seems to be for crime-reduction in general, and dedicates time to reducing the conditions that cause it (poverty, bad education, economic issues, etc). He hasn't shown much interest in political affairs outside of Gotham.

[Pokemon] What defines a Pokemon and what makes it 'legally' viable for battle?

What is a Pokemon anyway? And when is a Pokemon allowed to fight in a Gym battle? Now, of course most Pokemon are wild animals. Pikachu is simply a mouse that has electric powers. It gets a tad more confusing when it comes to more humanoid Pokemon or Pokemon with intelligence similar or greater than that of humans. Then later down the line we have Pokemon that are heavily implied to be extraterrestrial. Pokemon like Deoxys, Clefairy and Beeheyem. Then, later down the line we start encountering things that aren't even animals or creatures, but paranormal phenomena such as the living doll Banette, born out of spite for being abandoned by its child. Or Yamask, which is just a formerly human ghost. Not to be confused with the ghost of Marowak fought in Pokemon Red, which is not a Pokemon but a Pokemon's ghost. Not even getting into how the entire Marowak/Cubone line seems to be a paradox. But what really, really confuses me is the artificial Pokemon. Golurk, Porygon, Mewtwo, Genesect. How are these legal? Genesect is a crustacean with a cannon mounted on it. Is that really allowed by the official Pokemon League? Can I hand my Pikachu a gun and call it a new Pokemon? Can I send a drone into battle and claim it's a new Pokemon? At what point does something become labeled as a 'Pokemon'?

This was actually explained in the manga. Pokemon can bring tools if they are approved by the Pokemon league or used naturally. So man made items like Choice Band but also items they use naturally in the wild like Farfetch'd stick. A gun or knife would not be legal in an official league fight. Also Pokemon that exist as a permanent or semi permanent group naturally like Exeggcute or Magnezone are fine, but duct taping two Gyarados together is not. As for artificial Pokemon it's a bit less clear. It's hand waved by "league approved" but that gets a bit more complicated for Mewtwo and Genesect. Maybe Team Rocket has the league paid off with bribes and slowpoke tails.

ELI5: Why are so many small business restauarants cash only?

Such as take out Chinese

1. they don't like giving 3% (+/-) to the credit card companies. 2. they don't like waiting 30-90 days to actually get paid by the credit card companies. 3. they don't like to pay for the equipment 4. they don't like the risk of the customer rejecting the payment later on. 5. they don't like there being a paper trail of tips (taxes). 6. they don't like there being a paper trail for the business overall (revenue/taxes). edit: i will also add that in the case of Chinese take-out it is probable in some instances and in some locations that the banking system is inaccessible to some foreigners and some non-English-speakers, or that cultural backgrounds lead to less trust in banks and so on.

[X-Men] What's stopping Cyclops' laser from burning through his eyelids?

1) They're not lasers, they're concussive force. 2) His eyeballs are portals to another dimension. 3) his entire body is capable of blocking off that dimension except for his eyeballs. Even the thin eyelids are enough to shut off access to the dimension.

Eli5: If food/drink and oxygen both enter through the mouth how does the body decide which pipe to send each down?

Im asking because I just choked on a twistie

There is a thing in your throat called a epiglottis that moves back and forth as you breath and swallow. When you breath its in the upright position, but when you swallow it flattens out covering the foodpipe. When your done swallowing it goes back to upright. ELI5 Edition: Little piece of flesh that sits in the middle of the 2 pipes. when you swallow it closes your air pipe. When your breathing it stays open

ELI5 Why do jeans shrink after washing and then go back to normal after being worn?

Denim is a very strong material, it's actually so strong that it's used in paper money. When it gets washed and then heated up when dried, the fibers in the strands tighten up due to the heat. Wearing them forces the fibers back apart. It's actually what causes jeans to eventually tear because the fibers have contracted so many times that they lose their strength.

How does DNA function as an information storage medium?

I wanted to relate this topic to microarrays, but I searched and didn't find much about it.

There are a few layers to it, but basically the DNA sequence is read by proteins that transcribe the sequence into an intermediate message (mRNA). Those mRNAs are then translated by ribosomes into proteins, which then allow a cell to perform specific functions. Not all RNAs are translated, some perform functions in the cell. This movement of info from DNA->mRNA->protein is called “the central dogma” of biology.

ELI5: How are newer phones waterproof for 15 minutes but not 45 minutes?

Why isn't it a thing where the phone is indefinitely waterproof? Why does the duration matter?

The water pressure will slowly force water through the seams in the phone. However, the seams are so tight that it takes a while for the water pressure to force water through. But eventually it will.

ELI5:WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

Proposition 65 in California requires that products that are sold that may cause cancer be labeled. It's inefficient to label two sets of products - one for California and one for the rest of the country, so many companies will simply comply with the law in California and say that their product contains chemicals known to the state of California to cause cancer and birth defects or other reproductive harm. It was intended to be a consumer advocacy measure to protect its citizens from genuinely dangerous highly toxic materials, but that label is put on just about anything, so it's lost its meaning over time.

ELI5: What is the simplest way you can explain left vs right when it comes to politics?

I am a middle of the road kind of person and i think the money involved in politics is mind blowing. I grew up with grandparents on both sides, my parents vote republican. I don't see things the way they do and i seem to vote the opposite of them. Edit - i should add that my grandparents weren't communists after reading some of these comments.

**Economically** *Left wing*: taxation is (relatively) higher, but pays for more services, eg, hospitals, roads, police. Includes more state-owned businesses. This allows the rich to be charged more for the services the country provides than the poor. *Right wing*: taxation is lower, but services like healthcare, roads and so on are paid for at point-of-use, eg health insurance, road tolls. This means people only pay for the services they use. **Socially** *Left*: (generally) more progressive policies on gender, marriage, etc *Right*: (generally) more protection of traditional standpoints. Right wing can be associated with more individual freedoms, but looser business regulation, whereas the left wing tries to stop monopolies by restricting businesses. I have tried to keep this as neutrally-phrased as possible: if anyone sees any major mess-ups, do say.

ELI5: When I exchange currency, why is the exchange rate often given to 8-10 or more decimal places? Surely nobody, even when dealing will millions of dollars, cares after the fourth decimal place.

It seems so insignificant and unnecessarily precise to say "We're offering $1 = £0.8462485301" (as I've just been told by Amazon). As a consumer I only care about the first two decimal places. I can understand if you're trading currencies or working as a business maybe you'd care about the third and *maybe* fourth decimal place. But is anyone really looking at that thousandth of a penny in the fifth decimal place? I'm absolutely certain nobody is looking at the millionth of a penny. And yet most currency exchange places - both brick & mortar and online - offer this insane level of accuracy, providing 8, 10, or even more decimal places. Why? And how do they come up with such precise numbers?

I've worked in foreign exchange for a number of years. FX is bigger than all the rest of the markets put together; it's the great granddaddy of them all. Global FX trading volume is currently over $5 trillion USD **daily**, 5.5 days per week (the market runs continuously from the NZ open on Sunday evening to when the NYC markets close on Friday at 5pm). That's over $50 million per second. It's not unusual for single international transactions to be in the tens of billions of dollars, and professionally traded positions are always at least in the tens, if not hundreds, of millions. For ordinary people like you and me who are just trying to exchange cab fare at the airport, there's no difference. But at the volumes that drive the actual FX market, a change in the seventh and eighth "pip" (number after the decimal) is still a lot of money. (And if god forbid you should screw up your pricing and make a rounding error in those digits, there are lots of automated arbitrage desks out there that will immediately flood you with enough trades to bankrupt you.)

ELI5: Why does pregnancy and birth defects get riskier as women get older? Do their eggs expire, what about the sperm?

Eggs exist in a woman before she is even born. So the genetic material making up the egg gets older and more frail as time goes on, leading to higher risk of genetic malfunction, like downs syndrome. A dude produces sperm every 72 hours or so. It's fresh genetic material. But as he gets older he produces less so his chances of impregnating are lower. The risk of poor genetic material doesn't super increase though, like it does in an egg

[Harry Potter] Would Quirrell have gotten the stone if Harry didn't show up?

I am rereading Harry Potter, again, for the twentieth time. Something keeps bothering me, in the Philosopher's Stone I think Harry is at fault. Am I wrong?

He would not have gotten the stone no. The trick of the mirror is that Quirrel didn't desire the stone, the stone was just a means to an ends Quirrel desired the return of Voldemort. Most people after the stone wouldn't desire the stone they would desire the immortality it granted. It took someone that wanted the stone itself not what it granted that would get it, so Harry or maybe an archeologist.

ELI5 What happens when black holes collide?

While it doesn't answer your question, it's important to remember that black holes aren't actually super-vacuums in space. Objects in space aren't "sucked into" a black hole any differently than another object of similar mass, provided you're away from the event horizon. If the Sun instantaneously became a black hole, Earth would continue to orbit it like it did the Sun. Two black holes can even orbit each other.

If carbon and nitrogen are more electronegative than hydrogen (C = 2.55 and N = 3.04 while H = 2.2), why are methane and ammonia hydrides?

By convention (that is for historical reasons) all Binary compounds of Hydrogen (that is Hydrogen with ONE other element) are hydrides by name, not necessarily by reactivity. So, NH3, PH3, H2O, CH4, H2S are all 'hydrides'. The nomenclature is analogous to 'oxides' or even 'carbonates'. In many cases the isolation of these compounds was achieved before oxidation numbers were known or understood. The mass ratios and later mole ratios of the compounds were known. Back when this was done, there wasn't a particularly well developed sense of what chemical bonds were - the people naming them had no idea they were talking about (what we now know as) covalent compounds vs ionic compounds. The even more detailed ideas of Pauling Electronegativity was over century away: Ammonia was isolated in 1775 and the Pauling scale of electronegativity wasn't described until the 1930s!

ELI5: Why does Mongolia have such a low population?

I'm surprised that it has only 3 million people. Especially considering it is next to China who have well over a billion.

They were taken over by the Soviet Union who destroyed their culture, history, and natural resources leading to sharp economic decline. Their birth rate declined after the 70s sharply but is now rising again (59% of their population is under 30, one of the highest in the world). They also at one point had more Buddhist monks per capita than anywhere else on Earth, 20%+ of the population. Those guys don't have kids. The main reason is just that it's a small, landlocked country with economic troubles and not a whole lot of resources. It's kind of in the middle of nowhere, not particularly close to urban Chinese cities, surrounded by Siberia on one side and the massive Gobi Desert on the other side. All in all a recipe for basically zero immigration. China is many times the size, and has lots of coastal areas that have spurred trade, immigration, and a powerful economy.

Why do women have a hymen?

What's the evolutionary advantage of women having a cherry?

>What's the evolutionary advantage Something that exists in the human body does **not** necessarily have to have helped our ancestors survive. It's not like evolution chooses all the best possible features to create some super-being, "The All-mighty Human". Not at all. Evolution is very limited in what it can do. There are toms of things in the human body that serve no purpose, or are harmful to our health. A woman's hyman—a result of the development and growth of her genitals—does not prevent her from reproducing. It also doesn't do much to help reproduction either. So the hyman is an *evolutionary neutral* structure, meaning evolution *does not act on it*.

Are there solar systems of stars, where a supermassive star has a group of smaller stars revolving around it?

Even large stars don't have ridiculous masses, so all of the stars end up orbiting each other, so it won't be quite like a solar system with one in the middle. One of the largest and heaviest stars is UY Scuti, its about 1,700x as large as the sun, but only about 32x heavier so if you put it and the the sun in a system together they would both orbit the common center of mass which would be outside both stars, in our solar system the center of mass is within the sun so it seems we orbit the sun. There are larger multi star systems, Alpha Centauri is a triple system made of Alpha Centauri A, Alpha Centauri B, and Proxima Centauri. The biggest multistar systems i can find reference to is Nu Scorpii which is at least a 5 star system but believed to be a 7 star system, and AR Cassiopea which is known to be 7, this is about as close to a solar system of stars as you will find!

ELI5:How is it that although we don't know all of the words in the dictionary by heart, we can easily spot when something is not a word?

1. Recognition is easier than recall, so if you see a real world you usually recognize it, even if it's not one you use. 2. In a specific language, certain letter combinations are rare or completely unused. Here are some realistic non-words: famp, droom, pank. Here are some plainly unrealistic ones: qqaq, eoao, thethith, yfg.

Why do hands shake from nervousness or anxiety?

Would there have been any evolutionary benefit, or is it a side-effect of the normal functions of other bodily systems? Are there comparable reactions to fear in other species?

Everyone has some degree of tremor from the way that your brain and muscles work together. The normal tremor is called the physiologic tremor. Tremors are measured in hertz (Hz) or beats per minute. Physiologic tremors occur anywhere from 6-12 Hz (as opposed to Parkinsonian tremors which are 3-10 and essential tremor which is 4-8 Hz). Under stress (which could be psychological or mechanical like holding your arm out for a period of time), this tremor becomes exaggerated and is called an exaggerated physiologic tremor. The tremor is exaggerated because the muscle groups start to fire in groups. Adrenaline (aka epinephrine) enhances the effect. So interestingly, athletes can use beta blockers (like for your heart) to block the effect and reduce the tremor (that is why beta blockers are considered performance enhancing drugs in archery and rifle shooting).

CMV: Imposing Senator Term Limits would be in the best interest of all citizens for either party.

This would likely never happen, as our senators would have to be the ones implementing this decision. Fat chance they impose rules that put them out of a job in this economy. But I digress... ​ Lifetime senators do no service to their constituents. People like Mitch McConnell AND Nancy Pelosi know they're essentially set for life as long as they keep the favor of their party, because they aren't exactly in swing states. As it stands, the senators we currently have have the hands of various corporations lining their pockets and are abusing their power by utilizing their power to promote their own insider trading. We also have people who don't care to make good on any promises because there is no threat if they don't do a good job. ​ Term limits would mean that there would always be a position open and there would always be someone angling for the spot. Even if we had a round of 3 or 4 terms by the same party, it would always be a different congressperson. I believe this would force candidates to actually do something in their time in Congress.

>People like Mitch McConnell AND Nancy Pelosi know they're essentially set for life as long as they keep the favor of their party, because they aren't exactly in swing states. Not entirely. Both could be primaried and replaced with other candidates that align to their party, even in states that are not swing. They _aren't_ seriously primaried because they command power in the Senate/House, which is _incredibly_ beneficial to their home state. Having the Majority/Minority Leader or Speaker be _your_ representative is incredibly valuable. ----- But let's put all that aside. The problem with term limits is that governing is a job just like any other. You aren't good at it when you first start, and it takes many years to learn how to effectively pass law. Term limits sound like a good idea because you get "fresh blood" but what happens when you get a group of people who have no idea what they are doing in incredibly important positions? They get advice from whoever is there to give it, and those people would be **lobbyists**. Term limits would just give lobbyists even more power. Lobbyists will come with ready-made bills that the Congressperson won't understand, and that won't be good for governance at all. Moreover, with term limits, there would be nothing stopping Congresspeople from making sweetheart deals with lobbyists for post-Congressional employment because they know they are no longer accountable to the people. Term limits create worse representation, not better. They should be avoided at all costs. If people want a new representative, let them vote in a new one. If they like the one they have, that's great too. ----- So, why do we have term limits for the President? Well, that is a very unique position where the benefits outweigh the cost. No other position in government has _all_ of the power invested in a _single_ person, so the danger of one person consolidating power is incredibly great. Imagine a ruthless president that replaces all of the military commanders with folks loyal to _him_ rather than the country. That leads to dictators. Congressmen don't have that same threat - even McConnel has only 1/100th of the power of the Senate.

Why do Canada's police kill more people than their European counterparts?

http://theindependent.ca/2015/04/14/stop-the-killing-fatal-police-shootings-in-canada/

One answer is in the article you posted: >But that cannot be the whole story, because Canadian police kill more people in one year than UK police kill in 10, despite our countries having homicide rates in the same ballpark. **This seems to be the result of different approaches to policing; in particular, most police officers in the UK do not carry guns.** The typical British ‘bobby’ is expected to carry out her duties armed only with speed cuffs, a baton, and tear gas or pepper spray. Firearms are restricted to special units whose members have lots of experience and special training. If police in Canada were to adopt this approach, a lot of unnecessary tragedies could be averted.

What was the biggest cell ever existed on planet Earth?

Not necessarily a unicellular creature, it might even be an egg or a plant/animal with really big cells.

It depends on what you mean by biggest. *Caulerpa Taxifolia* is a single celled green algae with multiple nuclei, with a connecting root that can reach 3 meters and leaves that can go up to 30 cm. In terms of lenght, this is the biggest. *Syringammina fragilissima* is a single cell organism that can reach up to 20 cm diameter, it has a ball-like structure made of countless interconnecting tubes. It is then the biggest cell in terms of diameter. Ostrich eggs are the biggest in terms of volume and weight, they are 10-15 cm across and have no empty space in their volume.

[Rick & Morty] S3 spoiler - Rick takes down the galactic federation by setting their currency to 1 = 0, what would have happened if he set it to 1 = 2?

Depends on if it's a one-time calculation, or if it's recursive. If the money is only doubled once, nothing happens in the long term. You now have twice as much money, but so does everyone else. Prices would be higher, but you're also earning more, so it's a wash. Things might be weird for a bit, but eventually everything would stabilize pretty much the way it was before. Things get bad if it's recursive, though. Your dollar is now two dollars. But each of those dollars is also two dollars, and on and on... It would end up pretty much the same as the 1=0 scenario. Having infinite worthless dollars is a lot like having zero dollars.

ELI5: Is the 4th dimension something that we know actually exists? Or is it just a concept?

We have three spatial dimensions. Length, Width, Height. Using those three dimensions you can plot a spot in any space. We do not know if there are more spatial dimensions, if there are, they are likely to be things we're not capable of observing. What does it even mean to have a 4th spatial dimension, when you can plot any location in space using only three? That's beyond the scope of eli5. We have a temporal dimension as well. We don't know exactly what this temporal dimension *is*. We know what it feels like. It feels like the past moving through the present to the future. But Einstein turned that concept on its head when he declared the speed of light is constant. That's also beyond the scope of an eli5. Einstein called this Space-Time and it's the mathematical representation of both space and time as a singular entity, when you pull on one, the other is pushed. When you push on one the other is pulled. Space and Time are connected. But we don't know if time is an actual dimension, or if it's just the emergent property of having the ability to move through space while being constrained by the constant nature of the speed of light, which dictates that Space and Time *must* change, and that they change in ways that are correlated to one another.

ELI5: Why do colored pencils sharpen like crap in most sharpeners?

They aren't made with the same stuff as your Dixon-Tigonderoga. Standard pencil are made with graphite or charcoal, forms of carbon that is black in color. Colored pencils are made with wax or oil-based products that hold artificial pigments.

[StarWars] If Jabba the Hut is a weird space Frog/Slug why did he have sexy humanish Slavegirls?

Because he can? Any visible form of wealth and opulence is a status symbol for the Hutts. That can be slaves, vehicles, cities, starships, entire planets, debtors frozen in carbonite, they are all status symbols.

[Vampires] will any holy symbol do, or is it only the cross that works?

Okay, I am currently in Riyadh and there is this vampire going around killing anyone he gets his hands on. Problem is that I didn't bring along my vampire hunting kit with me (something about airport security and "youre not allowed to bring guns on the plane", I don't remember, I was kind of zoned out.) Now, seeing as I am in Saudi Arabia, and the chance of me finding a church here is nil, I need other options. Will the Crescent moon of Islam protect me against a vampire, or must it be a cross?

I am going to break with the consensus here, and say that anything will work, but that you don't have to believe in it. The *vampire* has to believe in it. Assuming the vampires in Riyadh aren't those bullshit "virus" guys with all kinds of odd science based weaknesses, the core essence of a vampire's being is selfishness and self-exaltation. Hence their common reaction to the icons of faiths. Even the most corrupt place of worship is ultimately and always about something greater than the self, about ideas of sanctity or charity or service or glory that are so antithetical to the existence of a vampire that the magics that drive them are simply incompatible with their presence. Think of it as the moral equivalent of scattering 100,000 grains of sand in front of the fiend. It's not the weak or strong faith of the wielder or even the particular beliefs behind the symbol that keep vampires at bay. It's that their mind simply boggles at the idea of true faith.

[LOTR] Why do the Nazgul wear cloaks if they are invisible?

What advantage do their clothes provide?

Intimidation, also disguise, a cloaked figure on a horse in the distance might not raise any suspicion, a riderless horse with reigns held up by an invisible force is another matter. Cloaks have been proven to help aerodynamics in flight.

ELI5 why when the window is open in a car the wind comes in so sporadically when driving

If air comes in it creates an overpressure in the car, which has to go somewhere. So air comes in and goes straight out after. This makes the horrible „wub-wub“ sound. So if you want your air to come in evenly, you have to open a second window, preferably in the back to get rid of the overpressure. Edit: This is also the reason your ears sometimes pop when you open your window.

Is getting published as an undergrad possible?

I'm currently in my fourth and last year of my undergrad in Communication, and I had the opportunity to complete some of my own research with the help of a grant. Now that the research is done, I want to publish the report. My supervisor said that it's a long shot, but I would like some second opinions. In particular, they said that me being an undergrad might immediately disqualify me from a number of journals. Do undergrads not get taken seriously when submitting to journals? Is the content of the manuscript the only thing considered with peer-review/publication standards? Any tips for an inexperienced researcher? In my admittedly biased assessment, the work that I have done is on par with many other articles I encountered. This is the closest I'll probably ever get to publish something, so I want to increase my chances as much as possible. Or at least be told honestly that I don't have a chance. Thanks.

Many journals review papers double-blind: the reviewers don’t know who you are, and you don’t know who they are. The bigger issue is that if you don’t have a mentor for this project, you may not know whether this work is new and noteworthy, and if they are you may still struggle with writing the paper in the manner they want. See if this professor can help guide you through the writing process, and that will help a lot.

CMV: Cemeteries need to be phased out and eliminated

I believe cemeteries are one of the biggest wastes in our society. They take up too much land that can return to nature or allow for new development. In addition, the embalming process has harmful effects on the environment that release chemicals into the ground. It also requires large amounts of fertilizer and water to maintain them. Some cities such as London expect their cemeteries to be full in 20-30 years. There’s not enough space and eventually there won’t be. Societies should revert to green funerals. This will allow bodies to be buried in nature without all of the funeral jazz. No embalming, no casket. The body can decompose and nourish life. Cremation is also the other effective option to go down.

Most cemeteries are a home for nature, even in big cities. They are home to a host of different plants, insects and birds. Cutting the grass costs money, so few cemeteries use fertilizer or chemicals. It's simply an added and unnecessary cost. Given the rapid decline in insects and birds, I'd say they were an asset rather than a problem.

Why doesn't a woman's immune system attack the fetus during pregnancy?

Since the fetus has different DNA from the woman, why doesn't her immune system recognize the foreign body and try to kill it? When people receive new organs they have to take drugs to suppress their immune systems, why doesn't that happen with pregnancy?

Cells of the mother's immune system cannot cross the **placenta** into the baby. Only IgG anibodies can cross the placenta into the babies circulation, all other antibody classes are too big. The IgG which does cross the placenta is what gives the baby immunity during its first six months before its own immune system activates. Sometimes these IgG antibodies from the mother do attack the father's antigens in the baby's tissues. This is most commonly seen where a mother's antibodies attack a baby's red cells. The reason this does not happen more often is that many of the antigens in the baby's tissues are not fully developed and the mother's antibodies do not readily bind to them.

Office mate is visibly struggling and trying to hide burnout- should I reach out? Need Advice

someone I work with has just experienced a really bad breakup and her latest round of numerical simulations have failed leaving her in a really bad way. I chatted with her last week when she was in the office but she's not been in the past few days. As someone who's dealt with frequent low moods and burnout I kind of feel well placed to maybe reach out and ask her how she's doing. As a guy I kind of feel this may be overstepping the mark and I don't want to give the wrong impression...

Nothing wrong with asking a colleague if they’re okay. If she’s a student, could also recommend the school’s free counseling services, or if she’s faculty/staff could mention their free services for employees (there’s probably a hotline they can can for one-off counseling or other services).

ELI5: How does Google/Apple Maps accurately measure traffic on every single road to predict trip time from origin to destination?

In addition to amount of traffic and trip time, how do they know if an accident occurs? I assume it has something to do with satellite imaging and/or tracking individual user’s location that are using the app on their phone.

There are quite a few sources of data. Crowd sourced information is very fast and high precision, but can be messy (is the traffic bad, or is this person just driving slow?). This kind of data comes from anonymized reporting while your phone is using its GPS. For example, while you’re using the turn by turn directions, you’re also reporting your own location data (anonymously) which gets combined with other people’s data and turned into one component of the traffic prediction. Another source of data is simply highway patrol. Different states (and countries) have different methods for determining and reporting traffic on major routes, but they almost always have something. This data is very curated and accurate, but sometimes lags behind a bit and only covers major roads. Despite the lag, it can still be a valuable tool for training the predictive model to better understand the more variable patterns produced by the GPS data. And finally of course you have accidents and construction, which are usually reported very quickly, again to highway patrol, and these usually have a comparatively predictable effect on traffic. They can’t be used to give high precision predictions on their own, but taken together with the rest of the data, they’re very valuable.

[Star Wars] How powerful would a force user with an advanced scientific education be?

Say a force user also had a degree in advanced physics. Would that help their force powers in any way? For instance, could a force user collect electric charge to fire bolts of lightning? Or agitate molecules so fast that they can make fireballs? Or create pulses of electromagnetic radiation to create an EMP?

Possibly *less* effective. Yoda says "you must un-learn what you have learned," suggesting that most views of how the universe works are incompatible with how the Force actually drives things, and are mere distractions to a Jedi. Also, you're demonstrating a serious misunderstanding of what makes a Jedi powerful. The most legendary Jedi Masters are known for using their wisdom to subtly shape destiny, not their telekinesis. Same goes for Sith Lords.

Why does boiling water make patterns in the cup?

https://imgur.com/gallery/EY84L24 Also apologies if the flair isn't suitable

Look's like the water isn't quite boiling. There's no bubbles, but this pattern that you're observing is indicative of temperature gradients in the water. So it can't all be at 100 degrees C yet. The temperature gradients cause gradients in the water density, which in turn cause variations in the refractive index throughout the water. This causes the light to refract (bend) at changing points in the water, leading to your observed changing pattern. If you brought the water to boil, you'd lose the pattern and have (ignoring the bubbles) a much clearer liquid as the water would all be essentially the same temperature. Edit: spelling

[Rick and Morty] What's Earth's current political status?

The Federation has collapsed, as well as their entire currency. But Earth knows about all the other civilizations in the galaxy, and vice-versa - do we maintain trade and relations with them? Or are we a backwater again?

Most likely backwater, as Earth (AFAIK) doesn't have the technology to reach out the other civilizations, and after the Federations occupation, few would want to. I would assume most humans would be at this point, somewhat xenophobic, if the little extra videos are anything to go by.

[Doctor Who] What does the Doctor think of his past regenerations?

We already know how much Ten loves Five. What does Eleven think of Four or so on?

Generally speaking, later incarnations tend to look down on/be annoyed by past incarnations, and past incarnations seem to be skeptical about later ones. The First Doctor treated Two and Three like children in *The Three Doctors*, which is odd as they're technically older and more experienced than him; what's odder is that they reacted like they were younger. Six and Two argued quite a bit, and Six treated Two like a disobedient child. Ten and Eleven got along better than any other pairing we've seen, except for their brief argument over Trenzalore; they behaved like similarly-aged siblings, despite having several hundred years (possibly) between them.

Why does light diffused from laser (pointer) look grainy, but other sources look smooth?

I'm a physics phd, and playing with my laser pointer today, pointing at objects that diffuse the light made me remember this question again. Why does this happen? I assume this is some coherence effect, but I can't come up with any train of thought into why all diffused light from laser pointers have the same grainy noisy effect while uncoherent light never displays this characteristic. EDIT: Confused the words collimation and coherence

It's not an effect of collimation, it's an interference effect from coherent monochromatic light. It's called a speckle pattern and it appears when the light is reflected either off a surface or scattered by some medium.

ELI5: How can some watches be more accurate than others?

I don't know much about watches, but I remember reading some watches only make a few seconds mistake each day, whilst others have larger error range. Isn't there a mechanical system that keeps the thing automatic? How can that create errors? Also some watches can remain accurate for decades, if one watch maker can do it, why can't other do it? I guess I'm just confused as to why there are errors and if there are errors, why some brands have larger margin of errors. Thank you in advance for your answers.

Quality control and tolerances. In any machining operation your parts have tolerances. A tolerance is how far out of the specified dimensions the part can be. Very exacting tolerances get rapidly more and more expensive, as they require much higher quality of both manufacturing equipment and labor, and a quality control system that is willing to throw away potentially very expensive parts for being a *tiny* bit too big or small. A mechanical watch with very tight tolerances will be very expensive to make, but it will be extremely accurate because you know to a very high degree of certainty *exactly* how all the parts interact. A watch with loose tolerance will be much cheaper to make, but won't keep time as accurately because bits and pieces are going to be a little bigger, or a little smaller, or a little heavier than they should be, and in unpredictable ways.

ELI5: Why have Asian-Americans flourished, while African-Americans remain under-educated & impoverished? Both were slaves here at one point, and both were heavily discriminated against throughout US history.

i'd like to point out, not all asian americans flourished. the ones you are seeing in the top of the sciences and engineering sectors are the ones that immigrated out of China on highly competed positions to be foreign exchange students and workers. the ones you are seeing as flourishing are the new generation of asian immigrants. the "old" generation living in chinatowns and opening up restaurants and gift shops are IMO stagnant. it's also the same reason why "all indian doctors are Patel's" because those people are the creme de la creme that have made it out of their originating country.

[Star Trek] There were a bunch of times Odo would turn into an Eagle and fly somewhere. But how could a 200lb bird possibly fly? Can he actually change his weight when he shapeshifts?

Odo has been used to compress metals and bend bulkheads by his mass and yet Sisko carried him around for hours as a satchel on Earth, smugglers unknowingly received him as a bag of latinum and Rom even carried him around on a drinks tray as a martini glass. Founders must have the ability to alter mass on the fly on a very fine scale without even realising it. If that's the case it's little wonder everyone wants to put Odo in a jar and study him. If it wasn't for the need to use him as a vector for genocide Section 31 might have disappeared him to a lab for the good of the federations future technological superiority.

[SW:TESB] So, a bunch of us crew members on the Executor were wondering how far Vader's power extends. The Admirals seem scared, but can Vader really kill everyone on the bridge or just one or two people at a time?

It would almost be preferable to have Vader kill everyone simultaneously. Unfortunately, in situations like this, he has a tendency to just seal the door behind him and go through everyone with a lightsaber. Is Vader powerful enough to break the trachea of each person in a room at once? Sure. But is it easier than stabbing them all? Does is send the right message to whomever has to clean up and spreads the rumors of the carnage following those who displeased Lord Vader? Really, it comes down to his mood, why he's so pissed, who he is trying to punish and/or send a message to, and if he is in more of a stabby mood or a chokey mood. Edit: also it seems uncharacteristically wasteful for Vader to kill everyone on the bridge crew of his flag ship. They were chosen for that post due to competence. Frankly, the lower you are in the totem pole, the safer you are. He prefers to make examples of leaders, not peons.

[Star Wars] Why does Yoda speak the way he does?

Presumably the way he speaks is correct grammar in his native language. You will sometimes hear people who have English as a second language use grammatical structures from their birth language when speaking English.

[Marvel] Can Bruce Banner get outwardly angry enough that Hulk is willing to let him have a moment before Bruce allows him to step forward?

In a scenario for example where Bruce has been grossly wronged and he wants to be legitimately angry at someone with the full intention of transforming, but getting his own chance to shine first? Would Hulk let him have a proper intelligent rant before Bruce "steps aside" for Hulk to bring the muscle?

Yes, if the Hulk and Bruce Banner are alike in mind then the Hulk will let Bruce get his licks. Bruce and the Hulk tricked Doctor Strange by changing back into pink, only to break the good doctor's arms as he transformed back into the green Goliath. So, lets say Betty Ross got backhanded by some two-bit skinny punk Chris Brown style. Bruce Banner would probably beat the shit out of him, *then* the Hulk. If both of them could they'd happily do a Hardy Boyz style, no-holds-barred, tables and ladders tag-team beat down they probably would. Then they would go back to hating each other.

ELI5: Why does eating salt increase blood pressure?

Table salt is composed of two ions, Sodium (Na+) and Chloride (Cl-). Sodium is easily absorbed by the body through rapid uptake, and it also tends to pull water along with it, by action of osmosis. The body uses Na+ for exciting cells, and also to regulate blood pressure by adjusting how much water is present in the body. The easiest way for water to move around is with Na+, because it's the most abundant ion in the body. Eating too much salt will increase the amount of Na+ in your body, and that also increases the water absorption, which enters your blood and increases the circulating fluid. This increase in fluid occupies more space, which exerts pressure on the sides of your blood vessel, translating to an increase in blood pressure. Your kidneys will eventually get rid of the extra sodium, but sometimes, for reasons not very clear, the body decides to keep retaining sodium instead, which leads to high blood pressure. Hence why you're advised to limit salt intake if you're suffering from blood pressure problems.

CMV: In a truly equal society, we must abandon the tradition of 'ladies first'

Early today, I was discussing with my father a time when, in a theatre, I didn't let a woman out of her row (thus breaking my conversation with the person in front of me) while we were walking out. His argument was that it's polite to follow the rule of 'ladies first'. I agree that, typically, holding a door open for the person behind you in a shop or other aspects of common courtesy are polite, but if our societies are to become truly equal, as we strive for, we need to leave the idea of treating women differently and giving them preferential treatment for things - being gentlemanly - behind with the other parts of discrimination which we hope to leave behind. For females and males to be completely equal in society, let's treat each completely equally. And surely that means forgetting 'ladies first'. _____ > *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!* Edit: We we’re walking as we left the theatre. We didn’t wait in the way of anyone. Clarification for one of the replies

How about we treat each other completely equally by being equally civil to each other? Maybe the shift in perspective shouldn't be that you're chivalrous to women only because they're women. Maybe we should treat both men and women with the same amount of regard. So, next time, let whomever pass, regardless of gender. It's only a step aside.

[Star Wars] Why is it that Jedi have many different variations in lightsaber colour while the Sith are stuck with only red?

Also, do the colours of lightsaber correspond to anything?

The color of the lightsaber blade is determined by the type of Crystal chosen. The the reason that you don't see Sith with more color variations is because they use a mass produced/farmed crystal in their light-saber construction. This allows for utility and uniformity. Sith do not need to "personalize" their tools the way some Jedi do. A lightsaber is just a tool to a Sith. Jedi more often choose crystals for their sabers that have some personal meaning. It could be tied to their Knighthood Trials, perhaps they found it on a mission, or perhaps the force led them to it. Each Jedi's Lightsaber is a very personal and customized thing. It is an extension of that person.

ELI5: How a manual transmission (and clutch) work

Basically what motors do is they spin a bar around in a circle very quickly. By itself a spinning bar can't make a car move, so something has to transfer the energy of a spinning bar into spinning wheels. What does this is a long system of gears. However, it's important that there's a way to change between gear sizes. If the gear system was fixed (as in, you couldn't change between sizes), then the car wouldn't be able to move efficiently at different speeds. Think about the gears on a mountainbike-- when you go up hills, you switch to a smaller gear. It turns the tires less per pedal, but it turns them with more torque (more forcefully). When you go down a hill, that extra torque means nothing, because you can't pedal fast enough to keep up with the size of the gear--so you shift up, and your chain moves to a bigger gear. this turns the wheels more times per pedal. To solve this problem in a car, there are transmissions. Inside the gearbox, there is a gear on the end of a bar that is retractable. It retracts when the clutch is depressed--and sure enough, the gear the bar fits into is the same one you can change with the stick shift. While the clutch is pressed, the motor is spinning fruitlessly, out of contact with the axle, but it allows the driver to change gear sizes to fit the current speed of the vehicle. Automatics do the same thing, but they have a much more complicated system that does it ... ... ... automatically Unless you were asking how to *actually drive* a manual...

Would Earths atmosphere get blown away if we would hit a gas cloud in space?

No. The densest nebula have about 10^4 particles per cm^3. The air you are in right now is round 10^19 particles per cm^3. It's like a mosquito slamming into a mountain. We would definitely notice something on the space probes which monitor the environment around the Earth. We might also get some pretty cool aurora displays, but at night the nebula would probably be barely to totally unobservable to the unaided eye.

ELI5: What is the so called Axis of Evil and why does it trouble astronomers?

Basically there is an underlying assumption that our universe should look essentially the same from any location, and that there's nothing special about where we are in it. The Axis of Evil is an anomaly in the background radiation of the observable universe, which appears to line up oddly with our position. If that were true, it would seem to suggest at least the possibility that the earlier statement is flawed, and raise quite a few questions about *why* our position is 'special.' However, there's definitely not strong agreement that this is actually the case, it has been suggested it could be coincidence, noise in how the data is processed, less significant than believed, or simply an error, among other ideas.

ELI5: Why do programmers hate using "GOTO" so much?

I just used it in a calculator program and it saved a lot of time and energy.

GOTO makes a program hard to read. The main reasons functions are used instead of GOTOs is that they are easier to modify, debug, and understand without going into details of how they are implemented. In a nutshell, functions may take a tiny bit more time to code than a GOTO, but GOTOs are really just hacky and break easily (but may be necessary if you don't have functions in the language you're using)