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ELI5:Time | Okay, I get the basics of time and how it works. What I'm wondering is why is it 'running' at exactly the speed that it is and how does that work? Has it always been running at this speed? What is there to indicate that time even exists? | Time is a human measurement of the environment that we live through. We measure it by an arbitrary scale that we invented/derived.
Basically though time is a measurement of change. Time as we think of it has existed from the big bang/creating of the universe.
Time does not "run" at the same speed everywhere as far as we can tell. It is confirmed that time passes differently at higher/lower gravity, or at high or low traveling speed. Our satellites in outer space literally have clocks that are running at "different" speeds than the ones on earth.
Time only goes in one direction because our consciousness only goes in one direction. We remember the past, but not the future. We can more or less easily look into the past, and know events happened in a specific order. | 21 | 27 |
ELI5:What do the scientists mean when they say the universe is flat? | We can clearly travel in 3d | Take a piece of paper and draw a straight line for a bit. From the end of this line, draw a line which is perpendicular (90 degrees) and draw about the same length. Now do it again, turning in the same direction. You should have a shape which roughly looks like this:
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Now pretend you do this on a globe. Draw from the north pole down to the equator, go 90 degrees a quarter of the way around the globe, and then turn back toward the north pole. You have a triangle with three 90 degree angles. This difference is due to the curvature of the surface of the globe and the flatness of the piece of paper.
When they say the universe is flat, they say that their experiments suggest that there is no large-scale curvature to the universe. We aren't on some sort of 4D globe. | 150 | 63 |
Why is Wittgenstein in (apperently) no introductory class to phil of language? | Viennese student here. I asked many of my friends in other (german speaking) unis about their introductory classes to philosophy of language. Everybody seems to be doing the “classics”, Frege, Russell, Kripke, Grice, Austin etc. I never understood why Wittgenstein is not absolutly mandetory in these classes? Both Wittgensteins, but especially the late Wittgenstein seem to me to be essential for a 101 class. Id love to here you opinions | The main reason for this is that Wittgenstein would take too much time, and you only have a limited time in those classes. As you may or may not know, Wittgenstein is not the easiest author to interpret/understand. In order to include Wittgenstein in an introductory class, you would have to dedicate a large number of sessions to him. Granted, Wittgenstein is a very important figure in the philosophy of language. But you want your students to have a grasp of the fundamentals of philosophy of language, and sometimes that means that you have to leave Wittgenstein out. | 55 | 82 |
What are some good books on feminism? | What are some good books I could read on feminism? | bell hooks' *Feminism is For Everybody* is a good introductory book on feminism and feminist topics. Other good ones are Marilyn Frye's *The Politics of Reality*, Sandra Lee Bartky's *Femininity and Domination*, and Patricia Collins' *Black Feminist Thought*. | 34 | 60 |
why do birds migrate back north? | In the summer arctic areas are full of insects which provide an excellent food source for young birds. Additionally, migration limits the number of competitors for resources as migratory birds have to dela with permanent tropical residents during the winter. | 12 | 17 |
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Do mosquitoes have any significant role to play in the ecosystem? In general what living beings have almost no role to play in the ecosystem? | Also, are all "plants" types important to an ecosystem because they are autotrophs (apart from some archea bacteria)?
The basic ecosystem (for me) is: herbivore, carnivore and omnivore. Mosquitoes - do they help in pollination? (like insects do).
If answer is no then one can also argue that even humans are not required, but I'd say the "brain power" we've got changes the answer to "yes" (imo).
Just a thought, (consider) for female aedes mosquito, the virus apparently lives in her, so in a way the mosquito is helping the virus, does it count as a role? At the same time viruses are neither living nor dead so do they really need a place to "live", also if the mosquitoes suddenly vanish can the virus "live" somewhere else, is there any problem here? | Mosquitoes are very important.
Mosquitoes actually play a role in pollination of many plants. As well mosquito larva are an important food source for many fish, frogs, and so forth.. and adult mosquitoes are important food sources for birds, bats, dragonflies, and many other animals.
Mosquitoes are insects by the way.
I suppose some total parasites might not have beneficial roles.. unless you consider that they help keep population levels slightly lower.. such as the fact that some animals are weakened by parasites and die.
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CMV: Employers shouldn't be allowed to fire employees based on any activities they do in their private life | I don't believe employers have the right to fire employees based on what they do or say on their own time. Even if the things done/said are morally dubious and shed a bad light on the company, as long as it's legal, the employee has the right to have a life without fear of losing their job.
As for companies, introducing legislation that explicitly forbids them from firing people based on things said or done outside of work would allow them to push responsibility off their shoulders (ie "our hands are tied, we know he's racist but we can't do anything about it").
My reasoning is that people should be able to engage in activities and speak their mind, in general live a free life, without fear that their company will decide it's not a good image for them.
Exceptions to this would include if the activity in question affects someone's ability to do their job.
The issue that sparked this post is the Roseanne issue. For those of you that don't know, the star of that tv show tweeted a racist comment, and had her show cancelled. Yes, it looks bad on the company who runs the show, but she is still entitled to express her opinions. Her company shouldn't be allowed to cancel her show on the basis of her political opinions in her private life.
(I posted this last night but realized I wouldn't be able to respond in 3 hours so reposting now)
EDIT: With regards to the Roseanne thing, I retract what I said in this post. The network would lose views because people don't want to watch a racist person on screen, which would cost them revenue. Thus, her actions and opinions do affect her job, and they were right in cancelling her show.
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> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | That does affect her ability to do her job. The network makes money based on advertisers that play during her show, if nobody watches the show or it becomes difficult to get advertisers for then it won't make money and they can't afford to keep producing it. | 86 | 185 |
[Terminator] How does the T-1000 work? | If he's liquid metal, where is the CPU, and how does he see and hear? He was frozen, and everything, hes 100 percent liquid, I don't get how the machine works.
(Also, just wanted to say I love this subreddit, I love the idea of it, I love the answers people get, easily one of the best). | Nanotechnology. Skynet wasn't sitting on their asses, they were innovating new and inventive ways to go back fix that whole Sarah Connor problem. What looks like liquid is really nanobots working together. | 17 | 15 |
ELI5: How are the different strains of marijuana different? How are they grown/modified to be different? | Generally speaking you have two main areas they can differ in.
The first relates to sativa / indica. Sativa has more of a "high", a buzzy, slightly awake feeling. More like coffee than alcohol. Indicas have a much heavier high, with more body effects, more of a sedating effect, and are a lot more like alcohol than coffee. This is the vast majority of the important difference between strains. Most people favour a hybrid, which just means a semi balanced mix of the two strains.
In terms of what those strains mean at the level of the weed itself, they relate to the levels of delta-9 THC (the principal psychoactive component of weed), and the levels of CBD's (less psychoactive, maybe more medicinally useful, probably more of an impact on body processes). THC is a psychedelic of sorts, CBD's tend to function as a depressant.
The other major thing they vary on is smell / flavour / appearance. Some people prefer super sticky moist buds, others prefer very dry buds (yes this is predominantly due to treatment of the buds post harvest, but the location and structure of THC crystrals on the plant plays a role). They can also smell like nice things - many of the names relate to what they smell like (supposedly). Frankly this whole variance point is close to irrelevant. They all smell predominantly like weed, and post harvest treatment carries more of an effect on the visual + tactile + smell aspects of the weed than the strain itself. The variance in CBD/THC ratios is the critical aspect
EDIT : made it clear post harvest treatment refers primarily to feel + smell aspects of weed | 55 | 115 |
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ELI5: How do DSLR cameras work? | SLR as a term is pretty well defined - it stands for "Single-Lens Reflex". Forget digital for a moment - remember normal point and shoot film cameras? You'd have a small viewfinder at the top, which you'd look through. Well, the problem with those is that you're not quite seeing the same as the camera lens sees - a bit like looking through a gun sight. They'll be close, and at a certain distance it'll be the same, but you're ultimately looking through a different window. In addition, this also means you can't easily use adjustable lenses because you'd simply have to guess the focus and zoom.
Well, SLR's solved that problem by having a mirror which moves. When you're not taking a photo the mirror is positioned so that the viewfinder is looking directly through the lens. In addition to being able to accurately compose the photo, this also means you can use adjustable lenses because you can physically see whether it's in focus or not. When you press the button, the mirror moves and exposes the film to exactly the same light you've been looking at.
DSLR is simply the digital equivalent. The mirror is still there, but instead of film you have a digital sensor. You press the shutter, the mirror moves, and the sensor can now "see" through the lens.
In day to day life, however, DSLR is somewhat synonymous with the idea of a higher quality camera. They generally come with additional features, better resolutions, better software and so on. But, strictly speaking, to be a DSLR they simply need that mirror system. | 90 | 95 |
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CMV: Making small assumptioms about a person based on their appearance is OK | I live in a very progressive and liberal area. Throughout my school career, I have been taught that you should not make any assumptions about a person based solely off of their appearance.
However, I think this is wishful thinking. A person's appearance is (for the most part) a *choice* by that person. I believe that this choice can reflect a lot about a person's character, likes, their social groups, etc.
I know that a person's appearance is by no means everything. I still treat everyone new I meet with respect and kindness, but I definitely take into account that person's appearance while doing so.
Thanks in advance. | Sure you can make assumptions about people's backgrounds. We give people clues about ourselves all the time in the words we use, our accents, or clothes, or hairstyles.
But if you are intending to assess a person's value based on their outward appearance, then you are mistaking the wave for the ocean. Cruelty isn't softened by a thousand dollar suit, and gentleness of heart isn't sullied by a tattoo. | 29 | 35 |
ELI5: Colour perception is typical described as a material absorbing light wavelengths and reflecting others, with those reflected wavelengths being interpreted as colour. EII5 how are light waves absorbed by a material? Is there a limit to absorption? | Materials absorb light by quantum interaction between the photons (light) and the electrons in the material. If the wavelength of light matches up to an electron properly, the electron can absorb the photon and jump up to a higher energy level. Materials have many electrons in many different configurations with many different energy levels so they can absorb a wide range of possible wavelengths.
It's not just the interaction of the electron with it's atom, it's also the electron bonds between atoms...that's why different chemical compounds can have different colours even if they involve the same atoms.
There's a limit to light absorption in the sense that the energy has to go somewhere, and it's typically going to show up as heat in the material. Eventually you get hot enough to cause the molecules to break down or change state (solid to liquid to gas to plasma)...either will change the electron configuration and energy and the absorption will change. | 225 | 836 |
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ELI5: Why is there a difference between your heart beating fast and beating hard? | During exercise my heart will beat fast, but not very hard.
However when I abruptly wake up from a nightmare or see a person I'd rather avoid, my heart will beat very hard but slow.
Why is it necessary for our bodies to have two different methods and do they achieve different effects? | When you exercise, your blood pressure is regulated by a combination of your arteries expanding, arterioles in the muscle expanding, and heart rate increasing. For any given increase in intensity, it takes 2-3 minutes for that change to fully occur.
When you’re at rest and under stress, your muscles don’t put out the same dilation (known as functional sympatholysis) yet your heart rate may still increase. In that instance, the heart has to pump more forcefully to overcome the blood pressure shift and maintain the same ejection fraction (amount of blood pumped vs amount of blood left in left ventricle). | 196 | 240 |
ELI5: What exactly is a major in Women's and Gender Studies? | I know that this is a more versatile degree than people think. I've heard it can be used for a job in marketing, writing, PR, and other general humanities jobs, but what exactly will you be in expert in with this degree?
It seems like an odd major. Not just because that it's use isn't readily apparent, but because MOST colleges seem to offer it. A lot of liberal arts degrees seem to be kind of hit or miss when it comes to which universities offer them, but WAGS seems to be a constant.
So... what is it? | There is a perception, particularly among feminist groups in the West, that a female perspective on all subjects (history, philosophy, economics, political science, psychology, sociology, geography, etc.) is lacking.
Women's studies is a broad category of studies that reinterprets these subjects and others through the lens of gender. | 108 | 162 |
ELI5: how do drugs like tylenol and advil know where the pain is and sooth a headache? | First, it's important to note that if you read the package inserts on medicine closely, you'll see that each notes that the actual method of action (the nitty gritty of how it works) is unknown, but the scientists/pharma companies have a pretty good guess.
Second, Tylenol and Advil are both analgesics (pain relievers), but are in different "classes" of drugs and work different ways.
Tylenol, aka acetaminophen, works mainly in your central nervous system (brain and spine). It inhibits the "reuptake" (think signal) of certain chemicals in your nerves that are responsible for telling your brain that you are in pain. So, it really doesn't "know" where the pain is in your body, it's just blocking everything. Think of it like a dam on a river... whatever it is that's causing your pain is still there, but now it's behind your tylenol dam and the only pain that's getting through is the little dribble that comes over the side.
Advil, aka Ibuprofen, is what they call an "NSAID" or "Non-steroidal Anti-Inflammatory Drug." It works mostly in your extremities. When your body suffers an injury, like a broken ankle, the injury site produces chemicals called "COX"s for short. Advil is attracted to those chemicals like a magnet. It goes to wherever those chemicals are and dams up the production. The reason why it works for your pain is because the chemicals that it slows down are responsible for all the blood rushing down to wherever your injury is and generally speaking, the less swelling and inflammation, the better for your pain.
Hope that helps. | 30 | 18 |
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First university paper in philosophy. A comparative essay on Nietzsche and Foucault. Any advice? | Hello! First year university student here. I have a paper due next week in my modern-postmodern philosophy class. I really enjoy the class, and it's preoccupied my mind way more than anything else I've learned in school so far.
But, I'm at a loss for my final! More or less I just don't know what a typical philosophy paper should contain.
Any advice? I'm thinking of comparing Nietzsche and Foucault on either "truth" or "language". But any points that anyone can suggest would be greatly appreciated.
edit - thanks for all the advice so far! Really helpful. I will definitely try to narrow down my argument. | The most important thing you need to do in any paper--but especially philosophy papers--is make an argument. Papers without arguments are purely informational and, unless that is the point of the project, insanely boring to read.
Your argument doesn't have to be complex, revolutionary, or brilliant. Your argument has to be well argued, and it ought to be interesting. You want to compare Nietzsche and Foucault on "Language"? Do you want to say Nietzsche influenced or didn't influence Foucault? Or that one of them got it right and the other got it wrong? Something more nuanced than that?
Since this is your first paper, don't be ambitious, precocious, or arrogant. Be smart and have something to say. | 10 | 18 |
ELI5: How do credit card rewards work, and can I really get free flights and such just by spending money? | I only have one credit card right now, which I am using to slowly build my credit by buying gas each month (anywhere from $75-$125 a month). I do not really know anyone who uses a reward card, but I've heard plenty about frequent flyer miles and other rewards and such. How do these cards really work? | Credit card companies make money in 2 main ways;
1) If you do not pay of the balance at the end of every payment period (usually a month, but there might be cards with other terms), they can charge interest. Usually this is a rather high rate.
2) Companies that want to accept payments from credit cards must pay the credit card companies for this. For this reason credit card companies give you gifts for using their cards. If you want those rewards, you'll use your credit card more often, which means companies must pay your credit card company more. | 56 | 136 |
ELI5: Why can't saltwater fish survive in fresh water? | Simply put, saltwater and freshwater fish have different systems for maintaining the right amount of water in their bodies. Think about salt, if you sprinkle it on a slug it makes the slug dry out, killing it. The same thing would happen to a freshwater fish if you plonked it in the middle of the sea. saltwater fish deal with this by clinging onto urea in their bodies. Urea is normally something we want to excrete because it's a waste product that gets produced by the detoxification of ammonia. Too much of even urea in your blood is very bad for you, let alone the deadly ammonia. However, saltwater fish are specially adapted to deal with this.
Let me explain something called 'water potential'. When you have something dissolved in water (a solute dissolved in a solution), we say that the water potential has been 'lowered'. The more that is dissolved, the lower the water potential. Water tends to move from an area of low to high water potential until it is balanced in both areas. The water actually moves both ways (its called a dynamic equilibrium) but eventually ends up with an equal concentration in both areas because of the random movements of the water molecules (the concentration of the solution = number of solute molecules per volume of water so larger volume of water needed for more solute).
By having urea in their cells, the water potential of the cells is roughly the same as the water potential outside the cells (caused by salt in the salt water) so no water movement occurs. hence, water does not gush out of the cells and leave the fish all dried up and dead.
Freshwater is 'purer' so has a higher water potential meaning that water would move into the fish cells, making them burst. Some fish can survive both environments due to different biochemistries but properly saltwater animals like sharks (excluding the bull shark) have this urea retention mechanism. | 11 | 39 |
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When and how do infants learn that their limbs “belong” to them? | Cognitively/neurologically, how does a child learn to distinguish between “an arm” and “my arm”? | Antonio Damasio's book Self Comes to Mind discusses this within the context of how our brains and minds develop a mind map of what and where our body is. The concept is ongoing and fluid, and can change if for example, you lose a body part, or use a tool for an incredibly long, repetitive time. The sense begins to form in the womb, but is refined continuously. Actual deliberate control of limbs, and consciousness of the separation between nursing infants and mothers occurs around 3-4 months. | 14 | 35 |
Question: How much should i charge someone for implementing a opensource program in their business. | Like the title says, I work in IT in a small country in Central America, I currently am very interested in working in small projects besides my job, i have a business question, i can manipulate and configure open source project like openemr for small clinics or independent doctors, but how much should i charge for implementing an opensource project in a small business, or how could I have a business model around it, I'd like to point out that I'm not interested in working for said business, just install it, configure it, provide some support and go.
Sorry for my English it is not my main language.
Is it wrong to charge someone for installing an opensource software?
Currently wondering about how to make some money with my current skill handling those programs | You should consider a model where you host it or keep it updated and provide paid support if they need it. Small businesses don't usually have enough money to keep a full-time IT person and don't know how to run their own software.
The value you provide would be keeping backups, ensuring the projects are secure, issuing password resets, upgrading, and patching. If they need additional help beyond that it's an additional fee. If you're going to be serving lots of the same type of business, you might also offer training and guides.
> Is it wrong to charge someone for installing an opensource software?
No! Lots of companies work like this, you're not charging for the software, you're charging for your understanding of the software. | 16 | 24 |
ELI5: Why is it that when a girl decides to give up her baby for adoption, she's applauded for doing the right thing, but when a man doesn't want to be a parent, he's a deadbeat? | What your describing first is the woman chosing to give birth to the child and put it up for adoption, rather than have an abortion. In this example you're talking about people applauding her for doing the HARD thing of actually bringing the child to term, and then giving it up to live in a better home than she can provide.
The second thing you're describing is when the mother keeps the child, but the father refuses to be involved. If the baby's given up for adoption, nobody cares about the father not being involved, but when the mother keeps the child, and the father denies it, that's a different situation. | 94 | 199 |
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Eli5 Why do some countries measure their currencies in large units? | For example in Vietnam, lunch can be bought for 50,000 VD and in South Korea, apartments can cost several MILLION Won. Why do some countries use such large denominations? | Usually these very large denominations indicate a period of significant inflation in the past. At some point an economic crisis made it necessary for the government to pump out currency to pay off debts or force investment, permanently devaluing the currency.
If you look back through South Korea’s economic history, you can see multiple inflation spikes in the 60’s, 70’s, and 80’s with rates hitting 30-70% - an already weak currency post-Korean War being further devalued.
Vietnam has a similar but more dramatic story: enormous triple digit inflation rates after the Vietnam War.
Sometimes nations do rebalance the devalued currency to reset the values. A few years ago Venezuela scrapped the Bolivar currency and converted it to Bolivar *Fuerte* currency to knock some zeroes off. | 431 | 453 |
ELI5: How exactly does "turning it off and on again" fix such a wide variety of different tech problems? | When machines start up, they goes through a routine to put everything in the right place.
It’s like when you wake up for school, brush your hair, put on clean clothes, and eat breakfast. You are ready for anything.
Well some days are very bad. Maybe you fell in a puddle, ruined your clothes, got your lunch wet. You never could have prepared for this and now your day is ruined.
Nothing you do will salvage this day. You can’t get the mud out of your clothes. You can’t eat that lunch now. Sometimes the best thing is to just call it, go home, and start over again fresh tomorrow. | 17,398 | 17,088 |
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[Star Wars] Wasn't anyone in the Republic bothered by the moral implications of creating a massive clone army of sentient beings strictly for the purpose of killing? | Can't help but feel someone must have been bothered by the fact that there are millions of people, being bred for the purpose of fighting in wars, what with all the emotional trauma that would go with that.
And yet Obi Wan just swans around the facility like it ain't no thang, what gives? | Even if they were, there are a few things to consider.
* Droids have some AI and are conceptually very similar to incredibly obedient clones (to the point of directly changing tactics whatever happened; eg giving Kenobi a lightsaber and then turning to shoot him).
* In the face of a coming droid invasion, there were few options available. The Jedi had no comparable army and this provided an easy solution.
* The clones had been produced at an enormous cost, and whether the jedi that commissioned them was dead or not (and whether or not they were to be used) they were going to be expensive. Why not use them?
* Clones are probably unusually equipped to deal with emotional trauma from war. There's no reason their breeders wouldn't see that as a weakness to eliminate.
* Conceptually, clones are a much more ethical solution than a conscript army. The clones are not going to be as troubled by the situation, they have no relatives, and they expect to go to war.
* Once Kenobi is at the facility, it is difficult to imagine him leaving instantly (the matter is too important not to investigate), offending the breeders (the jedi way is one of diplomacy and avoiding violence at all costs), or shutting anything down (he has not got the authority, given the army was commissioned by jedi). Therefore the only thing he can do is 'swan around', as you put it. | 67 | 82 |
Why shouldn't personhood start at conception? | Pro-lifers do not seem to care about the concept of "personhood" but rather just that human life is present.
Other than the example of abortion, where a persons bodily autonomy is removed in favor of a living human organism that is not a person, are there other problems that arise or ethical reasons why we shouldn't just take the religious approach and say that personhood starts at conception? | This paper might be worth reading for you:
Tooley, Michael, 1972, “Abortion and Infanticide”, Philosophy and Public Affairs, 2(1): 37–65.
But it’s also worth pointing out that the morality of abortion arguably doesn’t even depend on this point. The most influential defense of abortion is Thomson’s, and her argument grants it that fetuses are persons with a right to life, etc. and shows that nevertheless, abortion is permissible:
Thomson, Judith J., 1971, “A Defense of Abortion”, Philosophy and Public Affairs, 1(1): 47–66.
But see Tooley’s paper if you’re really interested in this particular question. (It sounds to me that you’re not terribly interested in abortion itself, but this issue is almost always treated in conjunction with abortion. Tooley’s paper is worth reading for the debate itself, even though he does draw the connection with abortion.) | 122 | 111 |
ELI5: If muscles are built by cells repairing themselves after being ripped apart, how come cancer in muscles isn't more common? | I actually found a TED talk referenced in another post under r/askscience. The talk discussed how muscles are naturally going to tear and reproduce so our ancestors who developed cancer in muscles died and the ones survived developed muscle cells that are more resistant to gene mutations. | 76 | 46 |
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Why is it that low-level languages like C are capable of dealing with system processes and higher level languages, like javascript, are not? | Forgive me if 'system processes' seems a little vague, I do not exactly know what the proper terminology is from an OS standpoint other than 'process'.
For example, Node.JS has http_parser built into it, which is written in C. In fact, Node.JS is built with both C/C++. As I understand it, this is because Javascript, native to the browser, is not easily capable of dealing with system processes, like reading files.
But then it turns out we need C to parse / request things via HTTP, something which is directly related to web-browsing, so why isn't Javascript capable of handling this itself?
Generally speaking, I am having difficulty understanding why some languages are capable of doing some things with your system and others are not.
I do understand some languages are by design much closer to machine code, but what I do not understand is why this merit gives them 'privileged' access to certain system processes and data.
Obviously I am not very familiar with computer science, any sort of ELI5 would help. | Many operating systems are written in C/C++ or similar languages. If C/C++ could not do everything you wanted (and this doesn't mean doing things is easy), then no language could those missing things.
Javascript is meant for operating in a specialized environment (web). There isn't a theoretical reason why the language couldn't do special systems things.
The big divide is really if the language has a concept of native assembly language. If the language can't generate native code, then it must have native code generated for it (a runtime environment), which limits the language to the capabilities of that code. | 21 | 23 |
CMV: I have no emotional connection to my religion. Having an emotional connection to a religion is strange. | I am a practicing Hindu. Every day, I try to meditate, chant mantras, perform rituals etc, I also burn incense, listen to bhajan (devotional songs) etc. I go to a temple meet up group weekly for around 2 hours.
Thing is, I don't think I feel any emotional connection to Hinduism at all. I don't care if anyone says anything that would usually be perceived as insulting about it at all. This is probably due to me constantly experiencing depersonalisation.
I just find the whole concept of being emotionally connected to a religion very strange. It's a religion, it has nothing to do with emotions.
Your challenge in this CMV is to convince me that feeling an emotional connection to a religion is not strange, that religion is linked with emotions and to convince me that I do in fact have an emotional connection to Hinduism.
​
Thanks in advance and blessings,
Abi | It's very possible that your religious practice differs from others, but for many people religion is a matter of deep personal faith that supercedes logic; it *has* to work on an emotional level. It isn't strange at all to have an emotional connection to that.
Additionally, experiencing depersonalization constantly is a very abnormal state of being, and as you note, that probably makes it hard for you to judge what a normal level of emotional connection is. | 23 | 15 |
Why is the imaginary number defined as i^2 = -1, rather than i = sqrt(-1)? | In case of i^2 = -1, there are two possible outcomes for i. So why wouldn't you just define i? | By starting with i^2 = -1 you are basically extending the algebra of reals with an object i that has that properity that is defined in terms of the operations of that algebra but if you start from the sqrt you have to deal with the fact it's multi valued. | 67 | 122 |
[Interplanetary] Is there any way to explain interplanetary warfare without starships? | The game "Interplanetary" is an artillery game wherein the populated planets of a solar system start engaging in all-out war, without actually possessing space travel. Or at least, good enough space travel for ships to relevant in war or successfully invade planets. So they start firing massive railguns at each other (Think "Stonehenge" in Ace Combat), and later nuclear strikes, giant death lasers, etc.
These planets appear to be engaged in the most extreme form of total war imaginable, with lore entries alluding to school field trips in armored school buses, building road tunnels to serve as improvised shelters, game upgrades like "mandatory fertility medications," and in-game radio-astronomy telescopes to try to spot targets on opposing planets.
It seems completely insane, and yet fascinating. Are there any circumstances where this could make some kind of sense? It seems like if you had this tech and resources you'd just be able to do asteroid redirects (it's a late game superweapon). And why are there multiple inhabited planets in a system that all suddenly decided they want to kill each other? If it's to take the resources, there doesn't seem to be a way to properly exploit it from other planets even if they won. | Multiple inhabited planets are able to detect the existence of the others as they develop technological. By the time they develop any form of two way communication (radio) centuries of fears and suspicions have left them predisposed to attacking first (in a get them before they get us first kind of deal). This mean that everyone is busy investing in ways to strike the enemy as quickly as possible while the longer term fields of rocketry struggle on in the background. | 13 | 33 |
How are time and space, according to Kant, a priori? | They're a priori for Kant because they're part of the conditions of possibility for our experience. They're the form of our sensibility, and are the form that appearances must take in order to be appearances for us. On Kant's view, we wouldn't have experience if we didn't have some form of sensibility, and we wouldn't have the experience that we do if the form of sensibility weren't space and time. It's not as if we just encounter space and time in experience; if that were the case, they would be a posteriori. They're needed for us to have experience at all, and so must logically precede all actual experience. | 18 | 18 |
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ELI5: Fundamentally, what is mass? | If you want go even further how are the particles that have no mass? | There are two types of mass, which as far as we know turn out, for reasons unknown, to be exactly the same:
- Gravitational mass is the quantity that determines how much gravity something has. According to general relativity, gravity is caused by objects trying to take the shortest possible path through spacetime: if their route through spacetime is bent, their path is altered, and we observe that as gravity. The more massive something is, the more it bends spacetime, and so the more gravity it exerts. Objects with no mass don't bend spacetime, and so don't gravitationally attract other objects (although they can be attracted by objects with mass). (edit - correction: objects with no rest mass still bend spacetime because they have energy)
- Inertial mass is the measure of how resistant an object is to acceleration. Heavier objects require more energy to accelerate to the same speed than a lighter object would. In a vacuum, massless objects travel at the speed of light without any force acting on them (although it's possible for objects with mass to travel faster than massless objects in certain mediums).
There's no known fundamental reason why these two masses end up being the same thing, as they're two entirely different concepts. However, the fact that they are the same is one of the fundamental facts which general relativity relies on.
Fundamentally, mass (both gravitational and inertial) comes from two places. First, via E=mc^2 , you have the mass resulting from the energy that binds the smaller particles together (e.g, gluons binding quarks together in a proton). For constituent particles like protons, neutrons, or atoms, this is the source of the vast majority of mass. Second, you have the mass of a particle resulting from its interaction with the Higgs field. The Higgs field is a field that permeates the entire universe and interacts with particles proportional to their mass: particles with a lot of mass interact with the Higgs field a lot, and particles with no mass don't interact with it at all. This interaction is mediated by the Higgs Boson. | 12 | 19 |
ELI5: What is the difference between mixing and mastering a song? | The most basic explanation is mixing is making adjustments to the individual tracks/instruments so that they mesh together best (adjusting volume of tracks against each other, adjusting eqs or the panning of certain tracks.)
Mastering is adding whatever final touches/effects to the track as whole once the individual tracks have been mixed together. This could be making the track fade out, adjusting the overall eq, or adding reverb to the entire track. | 18 | 26 |
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[Sherlock Holmes] How is Sherlock allowed to examine bodies? | If he isn’t in law enforcement or a family member of the deceased, how is Sherlock Holmes able to observe dead bodies to make his deductions? | Hes a well known detective asked by the police to aid in investigations or brought in by local lords and ladies. It's not an official chain of custody since those procedures were fairly rare in Victorian England and a lords permission or the constables was enough to give him access.
And if you're talking about newer more modern versions of holmes it's because he knows people at the morgue and coroners. For a few bucks they let him examine the bodies or simply because they know he can see things detectives may miss. | 56 | 26 |
ELI5: Why do highly precise mass scales fluctuate wildly? | I was preparing some samples today for dissolving, and I needed to prepare 0.001g and 0.0005g of material. The scale I was using had 5 decimal places.
Anytime I put a sample on there, it would go something like 0.00118g, then a few seconds later, 0.00090g, then another few seconds, it would even hit 0.0005g. That's over 50% in fluctuation!
What are the machinations of this phenomena? ELI5! | When you are trying to measure that precisely, even small variations in the environment can have a profound effect. Those scales measure the downward pressure on the plate to determine weight, so even a slight breeze from the labs A/C could put enough pressure on the plate to change the reading (that's the reason they have those sliding doors) | 48 | 114 |
ELI5: Did our ancestors experience vision loss similar to how we do? If so, how common was it and how did it affect their day-to-day survival? | Nearsightedness is largely a disease of urbanization and industrialization. populations like the Inuit went from like 0% nearsighted to like 50% nearsightedness in one generation due to urbanization. So our ancestors likely did not have that vision issue. But presbyopia, which is difficulty seeing near, starts around age 40 no matter the population, in most people. | 17 | 24 |
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Does anyone know what the deal is with Nature having a maximum article length of only 5 pages? Doesn’t that seem unreasonably restrictive? | So I was looking at [Nature's guidelines for authors](https://www.nature.com/nature/for-authors) and they list 5 pages as the maximum article length. Exactly what is the point of this limit? To me it just seems like it would be restrictive on content and what can be discussed. | Nature publishes short, data-dense reports on robust findings of extremely broad interest and significance, i.e. the sort of studies that are expected to have major implications for many workers across multiple subdisciplines. As such, Nature wants manuscripts to be honed down to just the information that is of interest to that audience. So, you won't necessarily get a thorough and exhaustive examination of the problem and data, but you'll get the greatest hits and the central takehome message.
People may complain about that, but realistically journals like Nature, Science, Cell, etc exist because no one can read everything and we need quick easy access to studies which may force us to rethink our approaches or assumptions in adjacent research fields or may force us to update lectures, textbooks, etc. | 138 | 77 |
ELI5:How come my body can heat up so much when I'm anxious but it fells like it barely does anything when I'm cold. | When you enter a cold environment your body starts preparing for extended exposure and begins conserving body heat through various means such as blood vessel constriction in the extremities.
Being anxious (and not out in the cold), is a stress reaction that does almost the opposite - gets the body and muscles ready for a fight-or-flight scenario, which among other things *increases* blood flow.
Thus one results in you feeling cold (even though your body is *preserving* heat), and the other gets your muscles prepped *at the expense* of producing and losing extra heat. | 22 | 91 |
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ELI5: What is the difference between Ashkenazi Jewish and other Jewish people? | There are two branches of Jewish origin following the diaspora from Israel - Ashkenazi and Sephardic Jews. Ashkenazi Jews are the ones who ended up in Northern and Eastern Europe... places like Germany, Poland, and Russia, and comprise about 80% of Jews today. Sephardic Jews are the ones who remained in the Mediterranean, such as Spain/Portugal, North Africa, and across the Middle East (there were even Jewish communities in Yemen and Iraq until a few decades ago). There are some differences is practice that developed over the centuries, but those have greatly diminished over the past century as Jews of both branches have ended up intermingling in the U.S. and Israel. | 37 | 43 |
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CMV: Reality is most likely very different to how we perceive it. | We perceive the world via our senses, things like sight, sound, smell and touch. But if we evolved without eyes, we would have no concept of color. I understand that color is determined by the wavelength of light, but we probably wouldn't even have a concept of light. In fact, without eye sight, we may not have asked many of the scientific question we have, so far.
How can we be sure that we are not lacking the ability to resolve other elements of reality due to our limited array of senses? Could there not be much more stuff around us that we are unable to interact with physically, or at least knowingly interact with it physically?
Perhaps that is were Aliens could exist? They could be right in front of us without our knowledge, existing in a non physical form or at least as far as we understand physical forms. I'm not saying Aliens are among us, I am just saying we may not have any idea if they were. Like I said, reality is most likely very different to how we perceive it. | >How can we be sure that we are not lacking the ability to resolve other elements of reality due to our limited array of senses?
Because we have machines with sensors that compensate for the limitations of our senses. We don't have the ability to see radio waves, for example, but we know they exist because we have machines that detect them.
>Could there not be much more stuff around us that we are unable to interact with physically
What does it mean for stuff to be "around us" if we are unable to physically interact with it? | 22 | 39 |
Eli5 - how can people get stabbed or shot in the gut/torso area and have it not hit vital organs or be fatal? | The term vital organs is key. The small intestines, not a vital organ, are 22 feet long in the average adult. You also have the stomach, also not a vital organ. That being said, you can still hemorrhage after being hit in one of these organs and die of blood lose | 36 | 32 |
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AskScience AMA Series: Hi! I am Prof. Nadav Davidovitch, an epidemiologist and one of the architects of Israel's coronavirus response and vaccine operation. Ask me anything! | Hi! I am Prof. Nadav Davidovitch, an epidemiologist, public health physician, professor, and director of the School of Public Health at Ben-Gurion University of the Negev (BGU). I study health policy, vaccination policy, comparative health care systems, public health ethics and global health. During the pandemic, it has been my honor to serve on Israel's national COVID-19 advisory committee, as well as on the COVID-19 Task Force of the Association of Schools of Public Health in the European Region.
My research focuses on various aspects of health policy, combining my multidisciplinary experience as an epidemiologist and public health physician with my knowledge of the sociology of health and public health ethics. I am involved in several projects related to legal and ethical aspects of public health practices, including pandemic response and health inequalities.
As a reserve medical officer during 2014's Operation Protective Edge, I was the commander of a medical unit of 700 physicians, paramedics, medics, and other medical personnel. I received my M.D. and Ph.D. from Tel Aviv University and my M.P.H. from Ben-Gurion University of the Negev.
I have authored or co-authored over 150 papers and book chapters, coedited 5 volumes and books and published work in leading medical and health policy journals, such as the New England Journal of Medicine, Clinical Infectious Diseases, Emerging Infectious Diseases, Journal of Pediatrics, Vaccine, Social Science and Medicine, and Law & Contemporary Problems.
Here are a few links related to COVID-19 in Israel that you may find of interest:
+ https://aabgu.org/mass-vaccinations-effective/
+ https://aabgu.org/covid-breakthrough-test/
+ https://aabgu.org/covid-mass-inoculation/
Learn more about Ben-Gurion University of the Negev: www.aabgu.org
I'll be answering questions starting at 11am PT (2 PM ET, 18 UT), ask me anything!
Username: /u/IsraelinSF | In terms of transmission how intertwined are the israeli and palestinian population?
I assume the vaccination rate of Irael does not count for non-israelis. Is the herd immunity effect possibly dimished by this? Since the "herd" is in constant contact with another non-immunised one. | 167 | 2,900 |
ELI5: Why does some smartphones get slower with time? Is it a hardware or a software problem? | Both
On the software side of things not only are newer programs typically more demanding, but newer operating systems are designed with newer/more powerful devices in mind.
As for hardware, the only real thing that degrades over time is the battery. As they age, and go through more charging cycles, batteries tend to be able to store less charge. What's more important for performance though, is that they also can provide less current. As electronics are under more load they draw more current, and if the aging battery isn't able to keep up then that effectively puts a speed limit on the device as a whole. | 24 | 25 |
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Which philosophy class should I take? Critical thinking and reasoning or existentialism focused on Kierkegaard, Nietzsche, jaspers, Heidegger, Marcel, Sartre, and Camus | Hopefully this is the right place to post this. Both of these topics are super interesting to me. I have an open elective in my science degree (geology) and would like to take a philosophy course to learn more about the subject as it is something I have always been curious about. Obviously philosophy is a very broad subject but which of these two would you recommend and why? Critical thinking would translate into other subjects better but existentialism would be very interesting as well. Let me know what you all think. Thanks | Critical thinking and reasoning is usually an introductory logic course. It’s really easy and will get your GPA up. However, it can be really dry.
Existentialism will probably be more interesting, but harder in that they likely won’t give out as many As and you’ll have to work for it a bit more. | 28 | 28 |
Does language define reality or not? (Sapir-Worf) | Hey all, its going to take me a moment to set this up so bear with me :)
 
I was in my class last night and the subject that was on the board was about the **social construction of reality**, which is listed as the process of people shaping reality through social interaction. Really neat! I am particularly fascinated with this subject as I think that language does determine reality.
 
In my textbook a couple weeks back I also remember us going over the **Sapir-Worf** thesis *really* vaguely. The definition of the thesis in the book says that people see and understand the world through the cultural lens of language, and goes on to say later that "evidence supports the claim that language does **not** determine reality". The book did not mention what *evidence* supported that claim, also didn't go into why sapir-worf isn't correct.
 
so which is it?
 
I'm confused as these ideas seem to contradict one another, people use language to communicate, then that shapes reality.. but it doesnt? (when I asked the teacher said "that's very interesting...and went on about his day... probably to be expected in the SOCIO 101 class in community college.. probably didn't want to take the time to answer me and waste everyone's time)
 
any light that you could shed on this question would be most appreciated. Thanks! | I think the important thing to remember about Sapir-Whorf is that it's not absolute. So when sociologists say that we construct our reality through through language or discourse, what they are saying is that the language we use reinforces values, norms and inequalities and our belief systems. Early proponents of Sapir-Whorf would say that people who didn't have words for certain concepts could never understand those concepts. That's where you hear stories about peoples who can see more or fewer colors or who can only count to three (supposedly the Piraha people of Brazil). But modern research has been skeptical of these findings. I'd encourage you to read Berger and Luckmann's The Social Construction of Reality if this is something that you are actually interested in. The book is challenging but very interesting.
Edit: Levinson, Stephen C. (2000). Yeli Dnye and the Theory of Basic Color Terms, Journal of Linguistic Anthropology, 10:1 (pp. 3–55). | 14 | 34 |
ELI5: How hormones are turned into pills | How are hormones such as melatonin harvested and put into pills? | It depends on the hormone. Each hormone is a completely different chemical and there are different ways of making them. Some hormones are extracted from other animals or plants. For example the meat industry have a lot of byproducts that is used for tons of different things including hormones. But plants may also be full of chemicals we want to extract. Another option is to find the protein that generates the hormone in humans and then encode the DNA that makes that protein into bacteria which then allows you to have a bacteria that will produce a lot of the protein you want. Another option is to make the hormone completely synthetically using techniques from organic chemistry. By mixing certain basic chemicals in a certain way using the right temperatures and ratios we are able to make almost any organic molecule we want.
Melatonin used to be extracted from cows however due to cost and contamination production have now switched to synthetic production instead. Famously insulin costs dropped to almost nothing over night when scientists were able to splice human genome into bacteria and start mass production using these bacteria. | 10 | 19 |
Does human vision have an aspect ratio? | The typical human binocular visual field spans approximately 125-135 vertical degrees and around 180-200 degrees horizontally. This gives an angular aspect ratio of around 3:2 for the bounding box in spherical coordinates. | 32 | 47 |
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ELI5: Why do so many Asian nationality adjectives end in "ese" (i.e. Chinese, Japanese, Vietnamese, etc.) where so many other nationality adjectives end in "ish" or "an" (i.e. Scottish, American, German, Egyptian, Italian, etc.)? I know there are exceptions, but in general, this seems to be a thing. | Edit: I mean nationality adjectives in English, not their native languages.
edit edit: For instance, Portuguese and Korean are exceptions, and then you have nationalities like "Czech" and "Filipino" which don't end in "ese," "an," or "ish." | We get our language/nationality names from European explorers who first made contact and had to call them something pronounceable.
Those ending in "ese" were countries first visited by explorers speaking Italian, Portuguese, or a similar language -- this ending is normal in those languages.
Those ending in something else were first visited by explorers speaking other languages. | 11,742 | 16,270 |
If mankind were to become roaming galactic nomads forced to live aboard giant spaceships, as Hawking believes, how would the structure of civilisation change? | It depends on the scope of the universe. If there is enough competition for resources, certain vessels may even attempt to attack others, in order to salvage from the wreck. If that is the case, those in the highest position of power may take their power from some sort of defensive presence, like the classic tribal hierarchy. | 10 | 33 |
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[The Culture or other post-scarcity utopias] How are raw materials secured and how is growth managed to prevent such a post-scarcity civilization from overrunning the universe in search of said raw materials? | In the Culture specifically, they have solved all of their energy requirements through a combination of antimatter and grid energy (energy siphoned off from the medium between universes), which is for all intents and purposes limitless.
They are able to manipulate energy at such a file level that they can read a human mind from light-years away. They generally *don't*, but they could. They can also transform matter into new states. For example, if a Culture vessel is going into battle, it might reformat the bulk of its mass into propulsion or weapons systems, and then undo this after the battle.
So basically, limitless energy gives them all the building blocks they need, and their technology then allows them to create whatever *else* they need, essentially from scratch. | 37 | 31 |
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how to know if a career in research is right for you? | I'm currently an undergrad studying biomedical science. I have the choice at the moment to either continue biomedical science at a different university in Sweden which is a lot better in the field and so go into research I presume, or to try and get into medical school (which I've heard it doesn't really matter where you do that). I could also change degrees entirely. I have no idea what I want to do, and I've never really done research before, how do you know if academia is the right path? | You should try it - probably volunteer at your university during the academic year or in summer - try to get into a summer research program such as Amgen scholars if you will still be eligible. But it seems in your case it may be easier to decide if medicine is right for you - e.g., how do you feel about making quick life-and-death decisions? and quality-of-life priorities, such as are you more interested in being able to work almost anywhere in your country of studies (medical doctors are needed everywhere, biomedical researchers in a smaller number of places) or in being able to work in other developed countries (that's typically extra difficult for medical doctors but common in research careers with non-human research subjects)? If it is, you probably should go to medical school, medical doctors are needed in larger numbers and more vitally. "Even" dentists and veterinarians. BTW as a medical doctor you can still end up doing research (though probably of a different kind, on people, such as clinical trials). | 10 | 20 |
What does Heidegger mean by Dasein having a "Vorontologischer Begriff des Seins?" | Heidegger frequently argues that dasein has a pre-ontological or pre-phenomenological understanding of being, but what does this mean? Does Dasein already operate with an understanding of das Sein selbst? But how is this possible? And does this have anything to do with dasein's nature as Existenz and it's Existenzialen? Heidegger attempts to search for the apriori conditions of experience and any conception of the subject, and he begins with dasein which is ontologically prior and analyses it's structures of it's being (Sorge etc) which ground any ontic approaches to the world or the subject. These ontological Existenzialen are more primary and closer to being, right? So does he think that from these concepts he'll get to Dasein's pre-ontological understanding? | Heidegger's method is understood to be "hermeneutical", that means trying to gain understanding of something that has meaning, and it has meaning because someone created it as being meaningful - therefore this someone himself already would have an understanding of this meaning. Therefore you could argue that "hermeneutics" is the art of interpreting not the meaning of something, but the creators understanding of it.
In other words: You can only try to understand what has already been understood. Therefore Heidegger claims that in order to understand the meaning of being, we have to assume that there's already an understanding of being prior to our project of explicitly understanding it. And since we as a particular being are able to ask the question of "what is the meaning of being itself", we already would have this kind of prior understanding, even though we can't express it yet.
And there's the difference between "ontological" and "pre-ontological": The project of "ontology" as a "-logy" is according to Heidegger "to make visible", or to express something explicitly. There's a pre-ontological understanding as in: it is lived, but not expressed explicitly (through language, respectively). The pre-ontological understanding does not have the form of a shared language. The "pre-" in "pre-ontological" therefore refers to the "-logical" part of "ontological".
Therefore the project of ontology is to transform this non-spoken, non-expressive understanding into a spoken, expressive, explicit understanding. Which is according to Heidegger a very hard task because language (as the medium of the being of "Man") tends to distract us, it tends to conceal more than it reveals. Therefore he realizes his "ontology" through the means of what he calls "formal indication": expressing the understanding of being itself in a way that it doesn't fully replace our pre-ontological understanding with a fully developed ontological understanding. Rather, it is being expressed only as far as it helps us to get in touch with our own pre-ontological understanding through experiencing it more vividly and more consciously. | 19 | 17 |
Why doesn't intel increase the size of the processor to make it faster? We're trying techniques to make transistors smaller, but would a 1 square meter processor outperform what we have now at the same transistor size? | Edit: I'm learning something new with every answer, great sub, thanks a lot. | Several factors:
* Job 1 is making money, and bigger processors cost more (and you can't necessarily charge more for them)
* Most of the die is not logic anyway - it's cache. You could make processors bigger now, and just not have so much cache (or have fewer processors, since most are 2 or 4 cores per die)
* Bigger processors are less power efficient, and everyone is on a power efficiency kick right now
* A new (and bigger) design carries a fair amount of risk - you spend a few hundred million dollars, and it might not work as expected. Plus, if it's really bad, you have no new product for the next cycle. | 963 | 2,556 |
ELI5: Why is dietary advice constantly changing and contradictory? | Fat was once the enemy now it apparently isn't, sugar is the demon, eat lot's of carbs/cut out carbs, X is the new wonderfood, never eat Y, eat red meat/go vegan... With so much advance in our understanding of the human body surely there should be a recognised standard? | Nutrition studies are very hard to do precisely, due to the amount of confounding factors, length of time required, small sample sizes and more. All these details get completely ignored by the media, who instead will print whatever new results have come out that gets them a nice headline | 24 | 26 |
Eli5. How its possible for the light to travel constantly with out stop slowing down from the most old galaxies? | Light is special because it has no mass and always travels at, well, the speed of light. This is one of its fundamental properties due to the laws of physics. You can’t really compare light to say, a spaceship, because it’s just not the same thing.
But almost anything can move long distances in space without slowing down. By default, things continue moving at the same speed they’re already moving unless something acts to slow them. On Earth, everything needs to fight air resistance or water resistance or friction with the ground to keep moving. But in space there’s nothing to bump into (at least it’s very rare to hit something) so if you do nothing, you keep moving. | 67 | 78 |
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ELI5- how do scientists know that a particular species' (panda, turtle, sharks, tigers) population is getting extinct? | They do studies to see how many of that animal there are in certain areas, and try to extrapolate outward from there. For example, if you know pandas can only live in bamboo forest, and you survey some random bamboo forest and find 1 panda per square mile, and you know there's only 100 square miles of bamboo forest left, you can make a guess that there probably aren't much more than 100 pandas. | 31 | 34 |
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How much energy does it take a bird to flap its wings during flight? Is it equivalent to humans walking/running? | Oh wow. Thanks for all the amazing answers and follow up questions. For science! | It varies by the type of flight and the species of bird. Most flight is energetically expensive, at least on a calorie per second basis.
Gliding is very efficient, especially with favorable thermals. Some birds can fly for hours without a single flap. This is roughly analogous to you standing on a bicycle while rolling down a hill. You could probably do it all day, but it's going to be tiring and make you sore.
From there, you have migratory birds which can fly large distances at high speeds. That is roughly equivalent to a brisk walk or light jog for you.
After that, it's a sliding scale of flight becoming more and more energy intensive. As a good rule of thumb the more agile a bird is, the more energy it needs to spend to stay airborne. This peaks with the hummingbird, which burns a staggering amount of calories staying airborne.
It's also worth noting that taking off is generally the most taxing part of flight for any bird. | 593 | 1,003 |
Philosophy, what is it and why do people study it? | ELI4 | **What is philosphy?** If you were to take a course an Intro to Philosophy course in college, you would learn about major schools of thought regarding human purpose, ethics, and rationality. The foundation of most of today's philosophy is based in Greek Philosophy -- the ideas of ancient philosophers like Plato, Aristotle, Socrates. Their timeless writings are still relevant and debated to this day. Their work has been built upon for many years and have gone in many different directions. Some of these schools of thought are in direct conflict with one another, such as utilitarianism (the ends justify the means) and deontology (the ends do NOT justify the means; it is about the best moral choice).
~~Philosophy is considered a "soft" science, similar to sociology. This is different from a "hard" science like biology or physics because it deals in intangible social issues: things that are difficult to measure and prove with hard data.~~ Philosophy is full of a lot of debate and semantics (determining the exact meaning of a word -- such as "morality") that don't always end with conclusive answers.
**Why do people study it?** People study philosophy to better understand the human condition. People want to better understand not only individual purpose (self), but collective purpose (all of humanity). People also want to better understand ethical issues, and argue for what they believe are the most moral choices. An example of a classic ethics debate is whether or not the "needs of the many outweight the needs of the few." Such questions are not easy to answer because they heavily depend on the context.
Nonetheless, people spend a lot of time contemplating these questions. Anyone can sit around and read about and contemplate these questions--most people do at some point in their life. But academically (at Universities), it has to be more than wayward contemplation. Therefore, like anything in academics, it requires a deep knowledge of past and current writings on the topic to provide a foundation of supporting concepts and ideas. This creates a web of supporting data to transition and progress into new or modified ideas.
At the end of the day, people who study philosophy hope to understand themselves and their world a little better than they did before. There are not a ton of career options tied to philosophy -- many who specialize in it often become professors of the subject, or move onto higher education that is more focused on something like law. The study of law is often intertwined with philosophy due to its connection to morality/ethics. Therefore, a background in philosophy is not a bad stepping stone into law.
More often, philosophy as college curriculum is taken as a minor degree, or a class or two in supplementation to a seemingly unrelated degree. Example: someone who is specializing in biological engineering may be forced to take classes in science ethics, which is rooted in basic philosophical principles. This is so they are able to better make choices in a career field that is full of difficult, complex moral dilemmas that cannot be answered with a microscope. They are questions that require subjective introspection.
**TL;DR- 42.** | 12 | 20 |
ELI5:The difference between a Federation and Confederation | Both a Federation and Confederation distinguish between the sovereignty of the individual members (e.g. states) and the the sovereignty of the whole (e.g. the nation or "Federal" government). Typically a Federation and Confederation differ in who has authority over the other, specifically in regards to conflicts.
In a Federation, the Federal government is granted power over the states whereas in a Confederation the power of the states trumps that of the Federal government. | 14 | 27 |
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Relationship in the lives of academicians | It takes time for someone who went for a PhD to get settled down with a permanent job which is pretty obvious. By that time, a person is near 30 or around 32 or more if we consider postdoc. How does uncertainty of which city/state/country(?) one may get a job relate to finding and keeping relationship a partner? This particularly happens a lot in faculty position. If one's lover or spouse has a job, how should the decision to move in other's city be taken?
There is a meme on internet that you either settle down for less or stay single. Jokes aside, once I read an social studies article where it shows that statistically male faculties more likely to have housewife (had a job but left) or wives doing a job she's too qualified to do because of moving with her husband. Female faculties may have faculty husband most likely (I forgot the percentage). Housewife observation may be relatively uncommon nowadays because of the changes compared to 30 years ago. Unfortunately I can't find the article again, so please ignore if you wish. However it is relatable.
I wonder about my professors how their life is (am afraid to ask such personal questions). It is more difficult for single academicians in a foreign country to find a partner (like me). From PhD to postdoc, you may need to change your place 2-3 times or more. I have checked my teachers's profiles and I don't know how they manage to do it if they had spouse at that time. Also, taking children is a parallel issue and a time dependent factor for female academicians if they want to. What do you think about this?
about me: I am a male grad student of STEM in his mid-20s. I have a plan to stay in academia, if not, in a research lab. I may do 1-2 postdoc (maybe?) in different places in future. I never had any partner and I am worried how it would go in future. I don't want to be a jerk asking someone to leave her job for me. I am even afraid to ask out someone I like because most likely we won't be able to stay together.
Any kind opinion and comment on my perspective will be welcome! Thanks for reading. | 1. Find a partner working in academia (at your grad or postdoc university)
2. Be kickass as you both begin your careers, and both apply to faculty jobs
3. Whoever lands the job at the better university, condition the appointment on also finding a faculty position for the partner
4. ????
5. Profit
Kinda tongue-in-cheek obviously, but that route seems to happen an awful lot. | 85 | 125 |
ELI5: If food gives us energy why do we get tired after a big meal? | Edit: Thanks for the answers! | Different definitions of "energy".
Food provides chemicals that your body needs to support its metabolism.
Feeling tired has no relation to whether or not your body has what it needs to function (except in extreme cases of starvation), but is instead a result of brain activity.
In short, "feeling energetic" is not caused by having chemical energy available for your body to use. | 13 | 19 |
ELI5: How is the breakthrough of the IBM 7nm chip is going to change technology and why it is important. | Computers calculate by turning a series of switches on and off in various patterns.
If a computer has more switches, it can perform more calculations.
But the bigger the switches are, the more power it takes to turn these switches off and on.
The more power it takes, the hotter it becomes, the more complicated the way these switches cooling has to be, etc.
So people make the switches smaller to put more switches on a computer on the same space to make a computer faster. That is why computers today are so much faster than in our fathers time, while they have become smaller.
The 7 nm process can be used puts the double number of switches that your computer today has in the same space. So it will take so much less energy to run so much more faster. | 27 | 18 |
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Was there a cultural reason for why Postmodernism developed primarily in France? | and among French intellectuals
as opposed to German and Anglo/Anglo-American philosophers? | In the context of philosophy, usually what people mean by "postmodernism" is what is more strictly called "poststructuralism", which is a response to structuralism and phenomenology, which had been the dominant intellectual currents in French culture. So the reason that poststructuralism largely happened in France is the more or less plain one that structuralism largely happened in France.
But analogous developments were going on in Anglo-American intellectual culture as well. They just don't get called "poststructuralism", because they're not responses to structuralism. Rather, they get called "post-positivism" or "anti-foundationalism" or "neo-pragmatism", or other such terms which situate them in the Anglo-American context. In the literal sense of being *after modernism*, or *using modernist strategies to critique modernist principles*, these Anglo-American developments are as much "post-modern" as post-structuralism is. | 65 | 34 |
Eli5 why are today's webcams so bad when compared to phone cameras? | I made a short attempt in streaming to Twitch during lockdowns and the pandemic. One thing I noted quickly was that the video quality differed immensely when I used an old android phone as a webcam compared to my then newly bought Logitech C920.
Why do they differ so much in terms of visible quality?
Edit: My webcam is a C920 HD Pro and cost me around $110-120 (1190 SEK).
Edit 2: I bought it a few years back. | The lens and sensor are only two of the four critical components of a camera
You need a good lens to get a lot of light onto the sensor. Most webcams are still using pinhole cameras while many phones have switched over to much bigger apertures, this results in brighter cleaner images.
You need a big sensor to collect the light that makes it through the lens and to provide you a lot of pixels to get the image quality you want.
But more importantly than either is that you need a signal processor and good storage connection to actually handle what's coming in. A 4k 30 fps camera will be sending 750 MB/s of data that needs to be processed, compressed, and then stored at least briefly in memory. The chip in your phone has a good signal processing segment specifically dedicated to the cameras with lots of hardware acceleration to help it with this job and connections to a large fast bank of memory, but its part of an expensive chip.
Your webcam is limited by the realities of its size, power allowance, price point, and connections. Most external webcams today are still USB 2 which restricts them to just 60 MB/s which means that they either need something that can get *really good* compression of the video stream very quickly to get their 30 FPS 4k video to fit down the connector, or they just film at 1080P and call it good enough.
The aggressive compression of the video stream combined with the tiny lens result in a sub part video quality for most cheap desktop webcams but there are good ones out there that sport a proper lens for good light collection they're just at a different price point | 440 | 1,001 |
CMV:US Citizens should not have to justify being in any public location with legal accessories including guns | So many people have argued that the Rittenhouse verdict was correct but not just, or that it was incorrect on the basis of "He had no reason to be there" or "he couldn't justify why he was there" or that "no one should go to a protest/riot with a gun no matter what", etc.
I think it was a bad idea, a dangerous idea, etc to do what Rittenhouse did. But I don't think we can or should condemn him or anyone based on simply being on public streets that were dangerous. I can't see how we get the restrictions on movement out of this argument. I don't mean legally, I mean even morally - who decides what constitutes a public place where certain people "can't go"?
Presumably, on different days, these same people wouldn't say Rittenhouse would need to justify being in Kenosha. Most of them explicitly say if he was just outside his house it would be different. So this would be a shifting curtailment of freedom of movement. What is the universal standard here? I've never liked "I'll know it when I see it" because it seems inherently ex post facto and just likely to be unfair and biased in application.
The final part of my view is that I don't think taking one legal activity and adding an accessory to it that is also legal changes any need to justify yourself. I see that all the time with Cameras - so many people get harassed for having a camera on them in public, even though it's perfectly legal. There is no need to justify having a camera in a public place. This is the same with guns when they're allowed open carry.
You could disagree with the law, but that doesn't mean I need to justify myself to anyone.
Anyway - if you have a coherent argument on why we should require people to "prove they should be somewhere in public" and have that play into their criminal or moral culpability, or clarify why carrying something legal is morally wrong because it bothers others I'll listen to it. | Choosing to go somewhere, and choosing what to bring to that place reflect on your intent or expectation. These things absolutely can be morally problematic, and depending on how strongly they imply intent they could also have legal implications.
Going to a fur coat sale is fine. Carrying a can of red paint is fine. Carry a can of red paint to a fur coat sale raises legitimate questions. Do you always carry red paint? If not, why did you bring it here? Assuming you don't usually carry paint, and that you aren't on your way to paint something, it's a reasonable assumption that you came to pour paint on fur coats, which is at least morally problematic.
Similar questions can be raised for guns even if they are legal to carry. Do you usually carry a gun? If not, and you felt like you needed to carry it to this place, why did you choose to go to a place where you felt unsafe? You could answer that you felt the counterprotest was important, but that you thought it might escalate so you brought a gun for defense. You could say you carry your gun all the time. You could also say that you wanted to bring your gun so that you could keep the protesters in line, and now you've entered problematic territory.
Our laws factor intent heavily into guilt and sentencing. We can't read minds, but we can look at the situation and deduce at least a bit of what the likely motives and thought processes were. Where we choose to go and what we choose to bring there are good things to consider in trying to determine this. | 34 | 23 |
Shouldn't time dilation prevent the creation of a black hole? | Because of relativity, the effects of time should almost stop at the event horizon. Doesn't that mean that a black hole takes an infinite amount of time to create? | The time dilation that goes to infinity at the horizon is meant between two observers that remain at a certain fixed distance from the black hole. To do so, they have to accelerate so as to fight the BH's gravitational pull. This necessary acceleration for not falling in becomes infinite at the horizon, another presentation of the fact that you cannot escape.
The surface of the collapsing star that forms the black hole, instead, is not doing this. It is (essentially) freefalling down, not fighting, and does not experience this particular time dilation. It does measure time dilation with respect to a distant observer, but it is milder and it does not go to infinity at the horizon. So the black hole can form in a reasonable sense.
Still you can imagine insisting on using an array of hovering observers watching it happen and relaying to you far away (this coincides with using the standard Schwarzschild coordinates). What you would see then is that the falling surface of the star slows down as it approaches the horizon and pancakes above it, never overcoming it and getting more and more redshifted; in the meanwhile the horizon grows pushing along the pancaked star outwards. The final result is a proper black hole with a "film" of star dimming exponentially fast. However, this is just one (partial) representation of facts, following from a choice of arbitrary coordinates. | 23 | 23 |
Marxist commentaries on Hegel | I'm looking for some secondary readings on Hegel written from a Marxist perspective. I plan to read The Phenomenology of Spirit, mainly because I'm interested in Hegel's relevance to Marxism. So, I would like to supplement my reading with some evaluations by Marxists. | Marx wrote a bunch of things obviously like *Critique of Hegel's Philosophy of Right* or the section called "Critique of Hegel's Philosophy in general" in the *Economic and Philosophic Manuscripts of 1844*.
Engels has a section on Hegel on *Ludwig Feuerbach and the End of Classical German Philosophy*.
Lenin has a few commentaries of some of Hegel's works in his *Philosophical Notebooks*.
Lukács' *The Young Hegel* and *The Ontology of Social Being Volume 1: Hegel*. Also the section "The Antinomies of Bourgeois Thought" on *History and Class Conciousness*.
Ilyenkov's *Dialectical Logic* and also a bunch of essays collected in *Intelligent Materialism: Essays on Hegel and Dialectics*.
Althusser's *Spectre of Hegel* is a collection of essays from his early writings.
Jameson's *The Hegel Variations: On the Phenomenology of the Spirit* | 15 | 17 |
Eli5 How does inducing a coma help save a life but if someone is dying you sometimes try to keep them awake? | Different methods for different situations. For instance, you want to keep someone focused and awake on you if you're trying to prevent them from going into shock, falling asleep while in the stages of hypothermia, that kind of thing.
Medically induced comas are largely used when dealing with brain issues. Perhaps a major artery was damaged and you need to induce a coma so you can actually operate on it. Maybe you want brain activity and blood flow very low so the brain can be less active, and perhaps recover from swelling or simply buy more time. | 35 | 40 |
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Where to start on big project? | So I had an idea for a project that is quite expansive, a lot of parts all working together. I've figured out most of how everything should work and what I need to do to implement different functionalities, the problem I'm having is because it's such a huge project I have no idea where to begin. Every time I start to do one thing I get sidetracked of on one tangent or another.
So my question is, when starting a large project how do you decide where to start or what order to do things? I understand this probably varies depending on the project but some generalizations should at least help get me on the right track, thanks in advance! | Start with a prototype of the Minimum Viable Product. Break down the functionality and build it up piece by piece. Deciding what that is is up to you and can only really come with experience. Just get started and have your plan/sprits/kanban sorted out for the functionality | 10 | 15 |
ELI5: What the hell is going on regarding Planned Parenthood | Trying to be objective about the situation. I'd like to hear from both sides what is really happening, why, and if it really is as bad as some people and the media are currently saying it is. | They donate tissue to research labs and are reimbursed for the costs of storing/shipping the tissue. PP does not profit from this. Research on fetal tissue, while perhaps unsettling to think about, is not illegal or immoral.
A right-wing group videotaped discussions with PP representatives edited them to make it appear that PP is gleefully murdering babies for profit. The group has been exposed as a fraud but they keep publishing the edited videos because a certain percentage of people want to believe the lie. | 42 | 19 |
CMV: Timed essays like the SAT don't properly measure one's writing skills, nor their critical thinking skills. | Timed essays, especially with as little time as the SAT gives, force test takers to come up with a BS answer without really thinking about it. As a result, they are either forced to justify an answer that they really aren't confident about, or they don't have enough time to write about their well-founded conclusion.
Consider the following essay question:
Do memories hinder or help people in their effort to learn from the past and succeed in the present?
This is a really interesting question. I wouldn't expect anyone but those that have already thought about it to formulate a truly essay-worthy opinion (one that they are confident in, and can truly justify it because they have thought through all facets that are apparent to them), and write about it in twenty-five minutes. If I don't have the time to truly form an opinion, how can you claim to measure this ability? It measures my ability to make a decent-*sounding* opinion in a short amount of time, and write about it.
I understand that test-takers are given a quote to consider before writing their essay, in addition to the question itself. This may indeed help people formulate their opinion, but it will also make it easier for test-takers to take a cookie-cutter opinion from the quote, which is really what many are forced to do given the time requirements, and write an essay without really formulating their own opinion.
Furthermore, everyone knows that one of the most fundamental aspects of good writing is good editing. Everyone's first draft in almost any form of writing is going to be poor. Ask the folks over at /r/writing if you're not sure. I know that the graders know that, and that they grade accordingly, but you can't really measure one's writing skill from a first draft. This is because the purpose of the first draft is really to put ideas on paper, and you get rid of the crappy ideas and crappy phrasing by editing. It really puts a damper on one's essay to have 25 minutes to write, even if one devises their argument in the instant they receive the question, and be forced to not only be rushed at the very writing of it, but to not have time to edit.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[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)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | The SAT is designed to measure your aptitude for college so that schools can determine whether you are qualified for their programs.
Most of the courses you take during college will have midterms and final exams that have time limits, and therefore the SAT accurately captures your ability to do well on those exams.
Of course schools do care about your writing skills as well, which is why competitive schools will ask you to write a specific essay for admissions which you have unlimited time and resources to work on. | 27 | 55 |
[BTTF 3] Why did Doc waste his time building the model of what they were going to do when it was just pushing the car with a train? Is Marty "special"? | It often helps to go over the details with actual models in order to foresee potential problems that aren't readily apparent when it's just in your mind.
Some law enforcement and special ops teams use models of buildings when they're planning a mission for this reason. | 38 | 31 |
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ELI5: What is it that gives a material the ability to be polished? | I've always wondered what it is that allows you to polish metals to a mirror finish, but not wood or plastic, for example? I assume its something to do with light scattering and reflection from the internal structures of the material? | There are two things that go into why a material can have a mirror finish. First, is whether light that hits it reflects straight back or gets scattered in many different directions. Smooth surfaces scatter less of the reflected light, and will be shinier than rough surfaces.
Any material can be polished.* Polishing is just making the surface smoother. Generally, the smoother a surface, the shinier it looks.
So the real question is, why are smooth metal surfaces extremely shiny and other materials not so shiny?
The second part of the story is that light is reflected any time it encounters a boundary between two materials with different indexes of refraction. The bigger the difference in the index of refraction, the more light gets reflected.
For visible light, metals have very large indices of refraction. The huge difference in the index of refraction between the metal and air can result easily in over 90% of light being reflected.
Explaining why metals have such high indices of refraction for light is a little more complicated. Metals have lots of free electrons that can move around inside them (that's why they conduct electricity). All these electrons interact strongly with the electric field of light.
Things like wood and plastic do not have many free electrons so they don't interact nearly as strongly with light. For example, when travels through air and hits a glass surface, only about 4% of the light will be reflected.
* It turns out that it's a lot easier to polish a metal than it is to polish wood. | 27 | 147 |
ELI5: Why does the propensity for motion sickness increase as you get older; e.g., riding roller coasters or other rides at amusement parks? | Balance is controlled by a group of small organs in the ears, called the vestibular system. These organs detect two different kinds of motion: rotation and movement in a straight line.
The way straight line movement is detected is that there are tiny little bones shaped like bits of stone that sit in a kind of sac that is lined with tiny hairs. When you move in a straight line, the little stones press against the hairs, which send signals to the brain that say “hey, we’re moving forward!” or “hey, we’re tipping over!”
The way rotation is detected is with three rings inside your ears. These rings are filled with fluid and more tiny hairs, and they are arranged in a way so that no matter which direction you move, the fluid presses on the hairs, too. So, if you did a cartwheel, one of the rings would say to your brain, “hey, we’re doing a cartwheel!” If you spin around like a ballerina a doing a pirouette, a different ring would tell your brain, “hey, we’re doing a pirouette!” And if you nod your head up and down, a third ring tells your brain, “hey, our head is nodding!”
The fluid in our ears is roughly the same as blood. Sometimes, that fluid thins out, which makes movements seem more intense than they actually are, which can cause problems with balance. Sometimes the little hairs in the organs will break away, and the spot where they were either sends too many signals to the brain, or none at all. This can also affect balance. | 85 | 204 |
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CMV: I think it is ridiculous for one ethnic group to be indebted to another based on the actions of people who've been dead for hundreds of years. | ~~For example - government funded benefits to people with even small traces of Native American genetic makeup. Is this really justifiable? Are the taxpayers who are funding these people's free income really responsible for the actions of men who lived hundreds of years ago - who they may not even have any genetic relation to? It gets even more complicated when we start talking about percentages - for instance, a person who is maybe 1/4th Native and 3/4th Anglo would qualify for these benefits despite the fact that the majority of their genetic makeup represents the people that they are claiming victimization by. But this is really not a relevant piece of the original topic - so don't feel obliged to include it in your arguments.~~
Edit 2: This example has done nothing but misrepresent my original thought, and I clearly do not have a strong enough understanding of Native American history to justifiably use it. Thanks to rigoding90 for making me realize this.
Note: My view extends far beyond any controversy involving Native Americans, to include any instance of this phenomenon.
Change my view.
Edit 1: It's currently 1am and I just realized that there are several very detailed replies to this post. I need to get to bed so I can get up in time for work tomorrow, but I will be reading through them in the AM. Thanks for taking the time to reply if you did. | The actions of people who have been dead for hundreds of years can have lasting effects if not adequately remedied. Don't think of it as necessarily a debt tracing back hundreds of years - think of it as an attempt to remedy a current inequality, the reason for which we acknowledge to be some past cruelty. | 64 | 132 |
CMV: Affirmative action is wrong. | Edit: I'm mainly talking here about quota style affirmative action.
Of course, racism is very real in modern society, but I feel that Affirmative action is the wrong solution.
First off, it's fighting racism with racism. It creates a system in which someone who is more qualified but in the majority might lose out to someone less qualified who happens to be a minority. Adding to this, there are few to none affirmative action programs support Whites in areas dominated by other groups. For instance, in my high school, we have a STEM magnet class. We take more advanced classes and have access to a research research program as well as apprenticeships. The program has an affirmative action program, yet despite this, roughly 80% of the members are of East Asian descent. If someone suggested an affirmative action program for people of European descent in the program, they would be labeled a racist. This reveals some level of hypocrisy.
This next reason is based on principle. Race and gender should not be taken into account when it comes to who is allowed in. Time and time again in history, we see that bringing race into policy only creates more problems. Why is this time different?
My third argument is this. It make people more likely to find some way in which they are "disadvantaged", when they really aren't.
My final argument is that affirmative action does not help the real issue. Let me explain.
Let's say you have a population split between group A and group B. Group A tends to have a lower socioeconomic status.
Level | part A | part B | Notes
-----|-----------|----------|-------
Gen. Pop | 50%(100,000) | 50%(100,000) | evenly split.
HS grad. | 25%(25,000) | 75%(75,000) | Here shows the racism.
num HSG qual. for Coll. | 12,500 | 37,500 | 50% of each qualify
accepted after A.A. | 50%(25,000) | 50%(25,000) | after affirmative action.
Here's the thing. After all of that, things are only "equal"on the surface.
Within group A:
25% are in college.
0% have only completed high school.
75% are high school dropouts.
In group B:
25% are in college.
50% have only completed high school.
25% are high school dropouts.
That doesn't look very equal to me! The issue that must be addressed is lower down.
Despite all this, I understand that my arguments may have flaws, and I always want to understand the other side of an argument. Adding to this, if presented with logic and facts, I will change my views. I try to live my life putting rationality above emotion.
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> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | I think it largely depends on the rationale for affirmative action - obviously each case or situation needs to be judged on its own merits.
In NZ for example Law and medical school has a small pool for indigenous applicants and interestingly restricts international students (because these courses would be absolutely overwhelmed with international students if totally open)
For the indigenous applicants it has *nothing* to do with equality, its hardly going to even and scales or past injustices etc, but its about trying to enhance the areas of law and health which are noted problems in their communities and having people within the culture qualified in the areas is thought to be a good way to target the problem.
So yes affirmative action is unfair, pretty much by definition, and its unlikely to be a balancing tool for unfairness, but it may be a relatively small cost of unfairness for a big benefit in some wider community issues. | 20 | 24 |
ELI5 Classical music is still relevant es ever. Nevertheless how come there are no longer super star composers like in earlier times and how do you actually transcend undying music of genius composers to be relevant today? | Yes, I am aware of world star performers like David Garret, Lang Lang but they still perform old repertoires 90% of the time. The closest star composer I know is Ludovico Einaudi but the music still sounds very modern and different. Is it because classical music no longer has a monopoly and because the world has become more diverse?
TL;DR where is the next Beethoven or Vivaldi?
Thank you
Edit: „as ever“ as opposed to „es ever“ | Well, the landscape of classical music changed a lot over the course of the last hundred and fifty years because there are other means of entertainment. It used to be that classical music was the music of the common man, but now it has the appearance of an aristocratic activity. Composers writing academic art music aren’t necessarily writing for a wider audience, rather they’re writing for academically trained composers like themselves. That doesn’t mean that there aren’t composers that everyone knows these days, take John Williams or Hans Zimmer for example. They’re writing for the most popular media of today just like how Puccini, Verdi or Wagner wrote for opera, which was the most popular media in the 19th century. | 208 | 181 |
HOW do sunflowers face the sun? | I'm not asking why, I'm asking how. It has puzzled me because they are the only flowers that do this behaviors. No other plants do this, so I'm wondering how it works. | Firstly, a correction; *many* plants display phototropism (movement in response to light source/s). In terms of flowers, many are named after this phenomenon with “heliotrope” in the name, such as the European Heliotrope, or the Salt Heliotrope.
As for the mechanism, there are two primary methods known. One uses “motor cells” which pump potassium ions into other cells nearby when exposed to light. This makes the pressure in the receiving cells change, while the pressure in the cells on the shadow side stays the same. Different pressures in the cells make them different sizes, thereby causing the flower to rotate. The other method is through actual cell growth rather than modifying the pressure in existing cells. In this method, the plants promote the growth of the cells on one “side” (either the light side or the shadowy side) more than the other, making the flower bend one way or the other. | 58 | 15 |
Why does the ISS maintain a radial-in attitude? | In almost every photo of the International Space Station, you can clearly see that the cupola module is always pointing towards the earth. That means that the ISS maintains a constant attitude relative to Earth and that it's spinning at 1 rotation/orbit (90 min)
I understand that it doesn't need any energy to maintain this low angular speed, but I assume that it does create some potentially avoidable problems:
• Small centrifugal accleration on the outer most modules.
• EVA astronauts will maintain the linear velocity of the spin, thus moving away from the station after they exit.
• Docking: I just can't wrap my head around how stuff could dock to the ISS if it's spinning at 4°/min (unless it stops spinning for docking maneuvers).
So why is it spinning? Just to maintain a view for the cupola at all times? Does it stop spinning during EVAs and docking? | This orientation helps decrease atmospheric drag, decreases chances of micrometeorite impacts.
This attitude also requires the least amount of energy to maintain (well an uncontrolled spin wouldn't require any energy, but that would cause a whole bunch of other problems)
And this means they can place antennae for communication in positions which always have a good view of Earth. Or for science experiments which need to always face towards or away from Earth. | 24 | 34 |
[Mathematics] What number refers to the number of possible orderings of natural numbers? | The number of unique orderings of a set of length n is n! and as such it seems logical to me that the number of unique orderings of the natural numbers is Aleph null factorial, but what does it mean to take the factorial of an infinitely large number as infinity minus one is still infinity(i think). I was also thinking about the Continuum hypothesis which says that the cardinality of the set of real numbers is 2 raised to the Aleph null. x! grows faster than 2^x so would that make the number of unique orderings of the natural numbers to be larger than the set of real numbers(assuming that we are able to take the factorial of Aleph null)? Apologies if my question makes assumptions which are incorrect, but thanks for reading! | A rather simple way to encode numbers between 0 and 1 to all possible orderings of natural numbers would be to create decimal number between 0 and 1, and type each integer in order, in base-2, then use 5 as separator. So if your ordering starts like 1, 5, 16, 4, 2, ... Then we'd have our encoding of
0.1510151000051005105...
Or to replace 5 with clearer separator
0. 1 | 101 | 10000 | 100 | 10 | ...
It's quite easy to see that if n'th digit of two orderings differs, then the encoding differs, so it's an injection from all orderings to the interval ]0, 1[, and as such, there are at most as many orderings as there are real numbers. | 17 | 35 |
Why do so many drugs end in HCl (hydrochloride)? | Hydrochloride salts of drugs are often easier to work with. The native form of the drug is often an oily liquid at room temperature, while the hydrochloride salt is a powder which can be shaped into a pill for easy administration. Once the drug is in your stomach, it dissolves into HCL + the drug. Conveniently, there’s already a lot of hydrochloric acid in your stomach, so adding a little bit more is basically harmless, and the drug can go on to the intestines to be absorbed into your bloodstream. | 56 | 21 |
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ELI5: How did they get, and keep, the footage of the atomic bomb tests? | You've seen the footage: those orange-red tinged shots of the car and bus being blasted across the desert, the shockwave hitting the trees and making a "forest" shimmy, and the house blistering into ashes.
So with all these thermonuclear torments, how the the camera stay trained on the spot, and how did the film not vaporize? What about retrieval? Don't get me wrong, I'm not some truther who's trying to say it wasn't real or the Freemasons did it (we had a pancake breakfast that day so we're good on alibis), or any such nonsene. Just curious.
Was camera tech good enough back then to have super long-range zoom? With the terrible force and energy, the shockwave pushing out and the negative pressure return wave what was used to stabilize the image? How was the recording possible with the presence of EMP? | First of all: for most shots of the blasts themselves, the camera was with the human observers i.e. sufficiently far enough away to be safe from massive shockwaves. Zoom lenses did not need to be super zooms, given the sizes of the explosions. Some cameras were put in massively heavy enclosures to survive being closer e.g. to capture the shock wave effects on structures and animals. You can design such things if you have an estimate of the conditions, which they did.
Plus: who's claiming that no cameras or film were ever destroyed? I'd be very surprised if that never happened! | 11 | 26 |
[Harry Potter HBP] Is Snape a good defence against the dark arts teacher? | The narrator presents Snape as a terrible teacher, presumably because he really wants the Defence against the dark arts (dada) job. Yet most his students seem to do well in Potions, taking O.W.Ls and gaining skills like polyjuice brewing (Crab and Goyle are even making it in the final book).
In spite of hating Harry, he still passes him to advanced potions and with the Prince’s (Snape) old potion book Harry learns more in that year than ever before. But we don’t see much of what is happening in DADA besides essay writing.
Is Snape doing anything in DADA to prepare Harry to fight the dark Lord or go after horcruxes? Is he giving the DA any skills to fight death eaters? | Snape is a good teacher in the sense that he's a very smart person who can deliver information clearly and answer any questions that come up. He's a terrible teacher in the sense that he's a bitter bully who will not hesitate to berate students that he doesn't like. So he creates an environment that's hostile - look at Neville Longbottom. He's a good enough study with a lot of self-confidence problems. Over the course of the books he starts to excel in most other subjects as he grows more self-assured, but he's never able to get that chance in Potions because Snape can't actually help someone with personal challenges, he can just tell them they're dumb for forgetting the order of a recipe. He seems to take a more theory-focused and less hands-on approach to DADA (at least at the level that we see), so he'd presumably be a fine teacher in that sense, though with less ability to inspire struggling students.
Also just a minor note - Snape isn't actually the one who passes Harry's OWL in Potions - those are administered by a separate Ministry-run group who test the students and grade the results. That being said, he *did* teach well enough that even Harry, who had almost no personal interest in the subject itself, was able to get an excellent grade. | 42 | 23 |
ELI5: How do cameras, or their lenses, auto-focus? | At first I thought that maybe the concept was a little similar to our eyes in that it tries to get as much of the incoming light on one point, the middle of the sensor, and so adjusts the focus ring until it finds a position with the largest amount of light on this spot. However, this doesn't explain (to me, anyway - maybe I'm just being thick) how a lens will be able to refocus on objects based on distance. | 2 ways:
- You digitally analyze the frame to figure out the least blurry lens configuration. Least blurry means sharpest color transitions between neighboring pixels. Only works in certain types of digital cameras.
- You measure the distance between the camera and the target, and figure out an appropriate lens configuration. Little IR sensors can be used to measure the distance. | 131 | 421 |
ELI5: Why do hot glass shatter when cooled down with cold water? | Glass expands when hot and contracts when it's cold. It doesn't conduct heat very well so when the hot glass comes in contact with cold water some of the glass shrinks faster then other parts which causes the glass to shatter. | 18 | 23 |
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ELI5: Why do men go bald solely on top of the head as opposed to on the sides or on the back? | There are different levels of "why".
There is something different about the hairs in that zone that makes them more sensitive to a particular hormone called DHT. There is a whole series of inflammatory events that slowly kill the follicle.
Now, why are the hairs in one spot more sensitive than the hairs in another spot? No one knows. | 181 | 577 |
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If refraction is caused by the absorption and reemission of photons, why don't materials only refract certain wavelengths of light? | It's my understanding that light seems to slow when entering a more optically dense medium because the photons are being reabsorbed and re-emitted by the atoms of the medium, which takes time and results in a lower average speed of light.
However, don't atoms also only absorb photons of certain energies? Wouldn't this mean that only certain photons with the right frequency would be refracted and those with other frequencies would carry on straight through? | Refraction is an emergent property of a material, that is, it only arises when there is a large number of atoms that the light is passing through. For instance, if you have 5 carbon atoms, that group of carbon atoms will not have the refractive properties of a diamond which is made of carbon.
So, how do large collections of atoms have continuous absorption patterns? Because large collections of atoms have many more absorption methods than simple electron promotion. Collections of atoms can vibrate and oscillate, using two to n atoms (where n is some large number) which allows a nearly continuous absorption pattern as they are many, many combinations. | 18 | 53 |
ELI5: How do thermometers work and how do they calculate what "it feels like." | Checking my phone for the temperature, I see that its currently 91 degrees but it feels like 99. Got me wondering how thermometers work/how they came to be and how they calculate "what it feels like." | Thermometers often exploit the fact that materials expand/contract depending on temperature, and different materials do it at different rate. The "feels like" temperature is a mix of the real temperature and the humidity. Humidity decreases the ability for sweat to remove heat from the body, so it makes the body heat up more than the same temp with low humidity. | 17 | 15 |
ELI5: How did the cameras that were used during the moon landing work? How were they able to broadcast relatively clear picture and sound from space, using 1960s technology? | I ask this because there is a group of people who think the moon landing *itself* is real but the tv broadcast was staged. I personally don't believe that the broadcast was fake, but the question piqued my curiosity and I would like to know how it worked. | Basically, the important thing in space communications is not the size or power of the transmitter, but the sensitivity of the receiver. Once you have compensated for local issues like atmosphere, other radio sources, the rotation and revolution of the Earth, etc, then the only thing that affects the transmission is distance, and we have lots of distributed, really sensitive receivers to pick up weak signals. | 156 | 456 |
ELI5: What are wavelengths and how does it relate to color? | What exactly are wavelengths, and how do colors have wavelengths? What exactly is a color? | >What exactly are wavelength?
The distance between two crest of a wave. Imagine an ocean with waves. There are high points and low points. The wave moves forward, but the distance between the high points stays the same. This is the wavelength.
>how do colors have wavelength?
Color is just light, and light behaves like a wave. Sort of. As light moves through space it has high energy areas and low energy areas which can be measured just like the area of high water and low water with an ocean wave.
>What exactly is a color?
Color is just how our minds perceive different wavelength of light. The same way our hears perceive the difference between high frequency and low frequency sounds, our eyes perceive the difference large wavelength and low wavelength light. Our brain then interprets that as color. | 38 | 56 |
ELI5: How/why is space between the sun and the earth so cold, when we can feel heat coming from the sun? | You need to distinguish between heat and temperature to understand this. The sun radiates energy, but it doesn't contribute to an increase in temperature until it hits something and warms that something up. Because there is nothing in between the sun and the earth, it is "cold". But if you were floating there, with the sun full on you, it would heat you up. They need to put reflective foil on spacecraft for this reason. In the shade of something, your body would radiate heat, which would make you very cold. | 9,055 | 11,511 |
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ELI5: Why do some light bulbs need to warm up, while others don't? | There are a few different types of artificial light in common use, and they all behave differently.
- The good old-fashioned light bulbs are called "incandescent." They work by making running electricity through a tiny little tungsten wire to heat it until it glows. These have to be warm to work, but they warm up completely in a fraction of a second, so they're pretty much instant-on from your perspective. Problem is, they're super inefficient and waste lots of electricity, although we've made some more refined varieties (called halogen) which run even hotter and use a bit less energy.
- Fluorescent bulbs are a newer, more efficient technology. Both the long, straight tubes in office lights, and the little twisty spiral bulbs at home, use this technology. They pass electricity through a special gas at low pressure, and the electricity makes that gas glow. These turn on pretty fast, but don't reach full brightness immediately. They keep getting brighter gradually over the next few minutes as the gas inside warms up. These are much more efficient, but some people don't like the gradual warm-up. They also contain a small amount of mercury, so they're not totally environmentally friendly.
- Vapor lamps are the worst offenders for slow warm up. It's so bad, they are only used for big lights which stay on for a long time like streetlights, warehouses, and school gyms. These work by using an electric arc to vaporize a little blob of sodium, which gets so hot it glows super bright. The lights take five minutes or more to turn on at all, and then they gradually get brighter over the next few minutes. That's just how long it takes to heat up the blob of sodium to melt and vaporize it. The reason we put up with this kind of lamp at all is that they're very efficient. The most efficient ones, for things light street lights, make a very ugly yellow light, so stores and schools and warehouses use a slightly less efficient type which runs at higher pressure and makes nicer white light.
- A new kind of light is called LED. These are little semiconductor devices, like computer chips. They're the most efficient type of all, and can be made into all different shapes and sizes, with all different colors of light. They also last a very long time (years or decades). And they turn on *immediately*. So fast, in fact, that you can turn them fully on, then fully back off again, *thousands of times per second*. We sometimes use this to our advantage, to dim their output very efficiently by blinking them on and off faster than the eye can see. The only reason we don't use LEDs absolutely everywhere is that, as a newer technology, they're pretty expensive. In the coming years, these will likely start to replace all the other kinds above. | 43 | 96 |
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ELI5 Why do our personal tastes differ? | Like, why does one person like chocolate but the other vanilla? Why does one person like pink and another blue? I understand genetics and how you are conditioned as a child play roles, but can one say more? | Our preferences and tastes are subjective to our own bodies and experiences. If you live in a country that has a lot of spicy food, like India or Mexico, you are more likely to develop a taste for such spicy foods.
As you said, genetics and hormones can also play a part. If you react painfully to chili peppers, you will grow to dislike spicy foods.
In a more general sense, out tastes are pretty random, because our bodies are random, our minds are random, and our situations are random. So, while shared traits can lead to reasonable predictions, like little boys in America favoring blue over pink because "girls toys" are colored pink, there is no set mechanism that will force or prevent a little boy from liking pink anyway. | 19 | 23 |
ELI5: Why does a company like Tesla or Uber have such high valuation (over 50 Bn) despite have low sales or losing money yearly? | Valuation is not simply a product of sales/revenue/net. It also has a growth component to it. The hope is that these companies will grow into profitable companies. So the value of the company today, is it's current value + its expected value at some point in the future.
| 66 | 168 |
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What actually kills a person when their body temperature is too low? | What is the first fatal effect of lowering a person's body temperature? I bet a lot of bodily functions cease to function at too low temperature on different scales. Is there a big one? Maybe one that occurs way before the rest. Thanks. | There are a strange set of physiological responses to hypothermia. In one sense, hypothermia can be preservative - the body's functions slow to a minimum - and is in fact used in some critical situations in hospitals. Humans can also survive a hugely depressed core body temperature. In fact, people are not supposed to be declared dead when they are hypothermic because recovery may be possible. There is a common adage among doctors that "you're not dead until you're warm and dead".
However, there are a number of physiological responses that could potentially cause death in hypothermia:
1. Low temperatures affect the electrical system of the heart. The channels that allow ions through them respond slowly and incompletely. So the heart doesn't get the signals to beat as fast as it should. If this continues, you can get what's called bradyarrhythmia (slow heart rate) to such an extent that the heart cannot maintain proper blood pressure. This could be fatal.
2. The cough and gag reflexes are suppressed in cold temperatures. You could potentially die from aspirating saliva or vomit.
3. Carbon dioxide production by the body decreases because the body is not metabolically active. Carbon dioxide is one of the major triggers for your brain to stimulate breathing. This is generally protective in normal physiological situations. This control system is broken in hypothermia and the brain may stop triggering breathing. | 48 | 32 |
Never thought about Grad School before but now I'm interested in something pretty specific and think it might be worth a PhD... | I really just need to pitch this thought off some people in-the-know who can set the record straight. I'm really interested in a topic that seems like it'd be worth it to pursue a PhD in. I'm interested in big data/machine learning in regards to genomics and its applicability to medical marijuana. How do I get a PhD in this? Where do I even start? All I have is a Bachelor's degree. Do I need to find an institution that is slightly relevant? Find a professor in a relevant field who can help/mentor? Can I even pick a topic of interest and pursue it? Are PhDs not really like this? Are they more strict/structured than what I'm thinking? Sorry for the dumb questions but googling most of this just brings up the scare articles about how people shouldn't go for PhDs... Not very informative about the inner workings of it all.
*****
**Editing to add:** BS in Computer Science, currently work at an R1 institution in the US in their IT department. Tuition assistance covers 1/2 the cost of grad courses. | If you have a computer programming background and foundational coursework in either biology or statistics, you may be competitive for a PhD program in computational biology or something similar. However, your research interest is currently too specific and needs to be more generalized. Specifically, you should be saying that you are:
"interested in big data/machine learning in regards to genomics and its applicability to ~~medical marijuana~~ human health." | 24 | 19 |
ELI5: What is happening when the shower water pressure drops and the water gets hotter? | If someone flushes a toilet or turns on the cold water it reduces the pressure in the cold water feed lines, and thus the total flow for any one open tap. Since the water coming from the shower is a mix of hot and cold, reducing the cold water flow reduces the total flow but increases the *proportion* of that flow which is coming from the hot water feed.
How strong an effect it has will depend on how close (not physically, but in terms of the pipe layout) the newly opened tap is to the shower, and the details of the plumbing system. | 314 | 179 |
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According to this chart, "Retirement Wealth" increased for white households during the recession. Why might that be? | I'm looking at data related to the racial wealth gap, and I'm wondering about why [retirement wealth for white households increased?](https://big.assets.huffingtonpost.com/RaceCharts5.png) Does this seem accurate? Is their an obvious explanation?
Data from this (old) huffpost piece (figure 4):
https://www.huffingtonpost.ca/entry/civil-rights-act-anniversary-racism-charts_n_5521104 | From the study the article is based on:
> This finding is consistent with research that suggests lower-income families are more likely to withdraw money from retirement savings after a job loss or other adverse event....Those families able to hold on to their retirement saving over longer periods (such as those who remain employed or have other assets to which they can turn) come out much better than those who sell when markets are low.
So basically it's a product of income and overall wealth. White households drew from their retirement funds less, and perhaps were less likely to be laid off, so they'd continue contributions to their retirement accounts, benefit from continued employer matching to those accounts, and bought the market cheap via continued contributions into those accounts during the depths of the crash in 08-09. | 22 | 19 |
If salt raises the boiling temp of water, is there additive that will let water freeze at a higher temp also? | Adding salt depresses the freezing point of water - that’s why municipalities salt the roads in the winter where it is snowy and icy.
Both the boiling point elevation and freezing point depression are types of colligative properties (in case you want to read more - use that term).
Colligative properties are about how the properties of a solvent (in this case water) can be changed by an added solute. It doesn’t matter what the identity of the solute is, it only matters how many particles are present (the particles essentially get in the way of the interactions between the water molecules).
Fundamentally what occurs is that you lower the vapor pressure curve of the solution relative to the pure solvent. This causes both the boiling point elevation and the freezing point depression. So there is no way to add a substance to water and increase its freezing point, because the solvent is still water. | 732 | 1,243 |
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How were sufficiently coherent light sources generated for optics experiments before lasers? | All the optics and photonics lab work I did as an undergrad a decade ago used a laser as the source due to its coherence.
I still don’t understand how the famous optics experiments (thin slit interferences, interferometers...) that predated the laser were achieved without that advantage. | For light sources to be coherent, they must be monochromatic (one colour) and have a constant phase difference between them.
The monochromatic-ness is easy to achieve, just use a source which produces only one wavelength of light.
For the constant phase difference, a single slit was often used before the gratings, or double slit, or whatever equipment the experiment was using. This works because the single slit acts as a point source, and therefore, as long as it is not moving relative to the other gratings/slits, will mean there is a constant phase difference between the sources.
Hope this is correct and answers your question :) | 724 | 2,412 |
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