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ELI5: why do we remember Marie Curie but not Pierre Curie? | 1. not the first woman to win a nobel prize
2. only won 1 nobel prize rather than 2
3. died in 1906 from traffic accident so any later accomplishments in life wouldnt be possible
marie's life was a lot harder than pierre's.
people who are actually knowledgeable about science history know pierre. | 176 | 156 |
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ELI5: why do we find the sound of the rain soothing but can't sleep if there's a tap dripping? | rainfall is randomized, and produces what’s called a broadband sound: a sound which has lots of different frequencies, or pitches, in it.
a dripping faucet is generally pretty regular, like a ticking clock, and each drop creates a sound that is more narrowband: it has fewer frequencies, sometimes even to the point of being a discernible musical note. it also has a single discernible moment when the sound happens.
put all that together and what you get is that the dripping faucet grabs your attention several different ways, and when your attention is focused on something, you can’t sleep because your brain is like “i’m working on something here! can’t sleep until we’re done with it!”
the rain has no features to latch onto, and in fact its broadband nature means it masks other intermittent sounds which might otherwise catch your attention. by giving you nothing to pay attention to, the rain allows your brain to relax and drift off. | 55 | 34 |
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ELI5: why do most lotions contain alcohol when alcohol is very drying for skin? | Alcohol is a big word that contains a lot of different types of chemicals. Some of them are dry but others are called "emollients" and they partially consist of fatty substances which help hold in moisture.
Putting them on your skin has a moisturizing and protective effect, and they also help in making the lotion because they hold some of the other chemicals together when their normal behavior would be to separate.
Note for adults: the FDA considers the common types of these emollients to be very safe. | 1,179 | 1,414 |
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ELI5 why some people are able to easily recognize when someone else is receiving sexual interest but is completely clueless as to when they are receiving sexual interest themselves | People tend to be more risk-adverse when it affects them personally. When you're judging someone else's interest in other people, it doesn't affect you as much if you are right or wrong (though for friends, you can have empathy towards their plight). When you are judging someone's interest in YOU, if you think they are interested and they are not, it could lead to changes in the relationship that personally affect you. Thus, it's easier to be on the side of caution when it personally affects you, causing people to dismiss these signs as friendly interest rather than sexual.
It also has to do with self-esteem and self-worth. You can judge others all you want but if you don't judge yourself worthy, you won't be able to accept that someone else may actually be interested in you. | 64 | 102 |
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How would a solar system with 3 suns work? | This has been bothering me since the release of pitch black | There are a few simplified cases:
-the stars orbit each other closely and the planet orbits much farther away
-the planet orbits one of the stars closely and then the three stars have their own orbit (Proxima Centauri b is like this)
-the planet orbits two of the stars that are close to each other, and the other star is farther away
Or there could be a chaotic many-body orbital system that may not be long-term stable | 28 | 16 |
I believe that despite religious beliefs, Jehovah's Witnesses children should be given blood transfusions if they are dying. CMV | I was talking to a friend about how hard being a doctor would be, and he asked me this: "What if a kid, about 12 years old, was dying, and the only way to keep him alive was to give him a blood transfusion, and he's a member of Jehova's witnesses? What if his parents would not let you do anything?"
My answer was that I would do whatever it takes to keep that kid alive, regardless of religious beliefs. I have a few reasons for this:
1. A child is not capable of making a decision at such a young age. They can't fully distinguish the full reality of death.
2. I don't think that religious belief trumps the right to life. This kid is going to die, but you'll allow that because he can go to heaven? I think that it's unfair to the child, and selfish of the parents.
3. A doctor's job is to save and treat people. Knowing that you could save a boy's life but can't due to one belief defeats the purpose of medicine.
I hope my arguments are good enough. If you have any questions please ask. And if you can, please, CMV.
| In case you are wondering about law and/or medical ethics, a doctor can and must give a child lifesaving treatment regardless of the parents' wishes. There are a few complexities about what counts as a child, but usually it's <18, and essentially every 12 year old would qualify. | 17 | 25 |
Is a vacuum cleaner's "sucking power" limited to the atmospheric pressure around it? | I feel like all a vacuum does is create an empty space by pushing air, and the "sucking" that happens at the end is just the weight of the atmosphere pushing air into the vacuum. So can a vacuum cleaner's suction only be so strong? I see some vacuums advertise high horsepower, but is there a limit to how much horsepower actually helps the vacuum? If i had a million horse power vacuum that spun way faster than a normal vacuum, would they both still have roughly the same suction, because that's dictated by air pressure? | You are correct that the pressure differential is limited by the atmospheric pressure, but what you aren’t considering is the volume of air moved. A vacuum of higher power will be able to move more air than a lower powered unit. Air flow is as important as pressure differential and you need both to effectively move material | 24 | 16 |
ELI5: Where does the term "cop" come from when referring to a police officer? | In the 19th century, the verb "cop" was used regularly to refer to the arrest of criminals by police officers. Eventually, the police officers were called "coppers," and, later, that was shortened to "cops." Other suggestions for the origins of the term "cop" have little support. For example, "cop" is not an abbreviation for "constable on patrol." It is also not a reference to large copper badges worn by some police officers of the late 19th century........(Cut copy and paste it from reference.com) | 21 | 19 |
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How to know the top Political Science (PhD) programs? | Hello everyone,
I am looking into applying to PhD programs in Political Science (next year), and most of my undergrad professors have told me to not apply to any schools outside of the top 15, but regarding this so-called "top 15," how do I figure out what those top 15 are? I genuinely have no idea. When people refer to these top schools, are they just referring to the U.S. News list? Are they looking at National Research Council rankings? What exactly?
I understand that there are some schools that are in the top no matter what the criterium (e.g. Harvard, Michigan, etc.), but I've been confused due to some schools that appear high in one ranking but low in another. For example, in the NRC ranking, Rice is ranked 4/15 in S-Rank ([https://www.chronicle.com/article/doctoral-programs-by-the-numbers-124714/?cid2=gen\_login\_refresh&cid=gen\_sign\_in](https://www.chronicle.com/article/doctoral-programs-by-the-numbers-124714/?cid2=gen_login_refresh&cid=gen_sign_in)), but in U.S. News they are ranked #33 ([https://www.usnews.com/best-graduate-schools/top-humanities-schools/political-science-rankings](https://www.usnews.com/best-graduate-schools/top-humanities-schools/political-science-rankings)).
Does anyone have a definitive list? For what it's worth, I'm interested in International Relations/Political Economy. I'm trying to compile a list of schools to do more research on so I can have an idea of where I'll be applying to, but I have no idea how to compile this list. | Poli sci Prof at R1 here:
Go to US News rankings. Sort by subfield, specifically international relations. Apply to top schools there.
Your advisor is twice as important as your school. Go to a place with multiple well known IR scholars. That way, when they write a rec letter, they recognize the name and are impressed. Plus you need multiple profs of this stature in case you don't get along with one.
European PhDs are a mixed bag. European countries treat the poor way better, and as a grad student you will be the poorest of the poor. At the same time, European PhDs are generally viewed as inferior because of their lack of standardized training in quantitative methods. Exceptions exist, of course. | 64 | 56 |
What is your opinion on Edsger W. Dijkstra's "Why numbering should start at zero?" | https://www.cs.utexas.edu/users/EWD/transcriptions/EWD08xx/EWD831.html
But I've noticed that many numerical programming languages like Fortran, Julia, Matlab etc. are using 1 as default base index. | Look at the languages in your list and Dijkstra's: they're all designed for scientists and mathematicians to convert mathematics into code. Typically in written mathematics indexes start at 1, so a language which starts array indexes at 1 is less likely to cause inadvertent errors when converting a formula into code.
For languages such as C and its ideological successors which were designed for programmers to interact more effectively with the hardware indexing from 0 makes more sense, because that is what the hardware does (see u/raevenos's comment). That's where Dijkstra is coming from, but it doesn't make him absolutely right in all contexts.
The reality is, which is "better" depends on what you're doing with it. | 57 | 37 |
I think college is way too easy and the number of people graduating college should be cut in half. | College degrees are becoming more and more valueless because just about anyone with half a brain and enough money to pay 4 years worth of tuition can obtain a degree. I'm a Junior at a major University right now and I can with all honesty say that at least 2/3 of my classmates do not put in any respectable amount of work towards their classes or are just plain dumb/apathetic. The Cs get degrees attitude is rampant, but the thing is that its true. As long as the university is getting their money they can keep churning out unqualified students with increasingly worthless degrees and it will only benefit them.
Without rarity there is no value, and without competition there is no rarity. Graduating college with a degree should be an accomplishment of one's intellect and hard work, not the product of paying tuition and doing the absolute minimal for four years.
This would also help ease the student debt problem. | I argue that the minimum level of work to graduate, in general, is still sufficient, and that there can still be much diversity between "A" and "C" level students.
First, a college degree, even if accomplished at the minimum level, requires more effort and yields more educational benefit than simply ending the academic life after high school. They're already distinguishing themselves from those without college experience.
Second, competition already exists - at least, for jobs. A person who puts more effort into their academic career is one who can put their knowledge into practice, minimize errors, and find experience in their field. The same could not be said for those who put in the minimum effort. An employer would likely identify and hire the former of the two, and the latter, if employed, would probably fail often.
So if you put more effort into your degree than your colleagues, good for you. It'll show when your experience and abilities beat the competition. | 21 | 41 |
CMV: Instead of deporting them, we should give illegal immigrants in the US a "yellow" card. | There are approximately 11,000,000 illegal immigrants in the US, significantly higher than any other country on Earth. That's a larger population alone than most countries. Trying to deport them all is like scooping water out of a sinking ship with a bucket. It's ineffective, there will never be an end, and not only are we wasting tons of money doing it but we are missing a myriad of opportunities for our economy and for humans in general.
So:
Implement a "yellow" card that is given to anyone who comes to/is in the US without a visa or green card. The card is tied to an independent database for recordkeeping. Certain citizens can also obtain yellow cards *if they choose to* (minors, felons, other people who may experience difficulty finding low-pay work).
1. Create a new type of business license that allows legal hiring of yellow card holders with strict parameters. For example, any business with fewer than x amount of employees and/or a projected revenue of less than $1,000,000 per year (or some other arbitrary number after some research) is allowed to hire x amount of yellow card holders as employees, *only* for eligible positions. (They can't be managers or supervisors, etc.) The federal minimum wage would be lower for yellow card workers, maybe $5 an hour instead of $7.25. States would determine their own minimums. The catch is, if the business winds up making over $1,000,000 a year, they will have to pay 33%-50% more in taxes, since they saved so much money on labor. They can then transfer to a standard business license, which would at that point make more sense for them financially. The idea is that it would make startup companies have a greater chance to succeed in the beginning when initial capital might be scarce and labor can break the bank, and more people be able to start businesses.
2. Implement a banking service for yellow card holders (maybe the post office thing could work here?). They would be able to have bank accounts at this bank, and obtain debit cards solely for domestic use, to increase economic stimulation.
3. They would be subject to our criminal system. Lawsuits could garnish their wages, non-violent criminals would be subject to community service, violent criminals... well, I don't know about those yet.
We could restrict the amount of public services they are eligible for, without trampling on human rights. Already, illegal immigrants (and legal ones) contribute way more in taxes than the tax benefits they receive. They would always be subject to inspection, and because their employment is now legal and recorded, we can actually determine which ones are beneficial and which ones aren't, and focus efforts on deporting only those who are not putting money into the tax pool. Because the card would grant a very limited amount of rights, if they plan to stay, they would be motivated to apply for visas, green cards, or citizenships which pay higher and have better benefits. Having a track record on hand would make the process easier for those who are good workers and have created relationships with citizens to obtain those visas and citizenships. Tons of new jobs would be created: the enormous increase in demand for goods and services would create jobs, the opening of an entirely new federal agency would create government jobs, the implementation of a government banking system would create jobs. If 8,000,000 people paid a 15% income tax on a $5/hr, 40 hour workweek, that's an extra $11.5 billion of annual revenue in income tax alone.
I know there are problems, obviously, but I'm convinced this is the start of an infinitely more effective system than what is currently happening. Change my view.
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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!* | Have you seen how guest-worker programs in countries like France work out? You create an underclass of people who are living among us but not as equals. They interact with us every day but have fewer rights. That's a recipe for social unrest, poor assimilation, and eventually violence.
Let people in or don't. If they're here, they should have the same rights as everyone else here. | 43 | 26 |
[Comics] Could a character with a healing factor contract parasites or a bacteria that resides in, say, their intestines? | Would their healing factor kill the intruders even if they aren't in the bloodstream? | Depends on how the healing factor works. Some like Wolverine or the Hulk could probably expel/kill the intruders, but someone whose power is just healing faster than normal (like the Flashes or other speedsters) wouldn't. | 19 | 25 |
[Star Trek] A question about starship design | What was the point of the saucer/body [design](https://upload.wikimedia.org/wikipedia/en/5/54/USS_Enterprise_%28NCC-1701-A%29.jpg) of the Federation Crusiers? Is it a simple design aesthetic or is there some purpose to it? | Originally, this design of saucer - hull - nacelles was the optimum for generating a warp bubble around the ship, while still keeping the crew safe and the Gravity and structural integrity fields from interfering. | 22 | 15 |
How do you come up with solutions to algorithms | I’ve recently started studying data structures and algorithms and I’ve been having a hard time. The problem is not understanding solutions but how to come up with them. I constantly find myself just looking up the answer when attempting leetcode questions after not being able to come up with a solution. So what I want to know is how should I study and practice in a way that teaches me not just the solution but ways to come up with solutions. Any help is appreciated. | 1. Think about the problem for several hours
2. Write code that doesn't work for a couple days
3. At some random time, like driving to the grocery store suddenly realize the solution
4. Log into work at 9 PM and implement solution in half an hour before you forget
5. Wake up the next day and try to explain why the thing you did works in a code review | 10 | 15 |
ELI5: If I have a 1 light year long stick and push it, why does that information not travel instantly? | Information travels through materials in a wave at roughly the speed of sound in the material, not light. When you push on the end of a stick, you are pushing on atoms that then have to push on adjacent atoms, which push on adjacent atoms, etc.etc. until the far end of the stick moves. There is no such thing as a perfectly rigid object. | 150 | 77 |
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ELI5: Why is 24 FPS unplayable in video games, but looks fine to me in movies/TV shows? | A lot of these responses are correct but are missing a critical point; That is that games require input and interaction while movies and television are passively observed.
When a game renders a low amount of frames per second, *especially* when it dips under ~30 FPS, the player can feel the difference much more because it takes more time for input to be read and then displayed on the screen.
In other words, this means that every action a player makes in such a scenario feels sluggish and unresponsive because when our brains are expecting to perceive a change much faster than we do. It can cause an element of frustration and it certainly does not help in immersing the player into the game as they are effectively being constantly reminded that something is wrong.
Television and movies on the other hand require no input from those watching it so utilizing lower frame rates - so long as they are constant - is far more comfortable than if we were to play a game at the same FPS. | 788 | 1,006 |
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ELI5: Why do wet clothes appear darker in colour when wet, even when water is colourless? | And further to this, why do some clothes appear see through when wet? | Water increases the scattering angle of light on fabric, and as a result, light is reflected and refracted in a greater number of "directions" than it is from dry fabric. Your retina is therefore receiving less overall reflected light. Since our sense of sight is simply a sophisticated means of making sense of a wide array of complicated light signatures, your brain interprets this as being darker. | 50 | 71 |
[Most Human Futures] Why in almost every conflict in almost every future universe is there a guy with a shotgun? | Shotguns and their equivalents are seen in almost every future conflict. From Halo to Aliens to Warhammer 40K. In almost all of them there is someone with a shotgun blasting their foes into quivering bits.
Why? What makes the humble shotgun into an omniversal weapon? | Its a design that works and is easy to maintain/understand.
If you need a door breached? Shotgun.
If you want to frag an alien that is closer than twenty feet? Shotgun.
If you want to provide for your family, so you go out hunting fowl, and run across some mutants trying to steal your shoes while quoting heretical obscenities?!
I think you know the answer.
The humble shotgun. Why improve perfection?
| 36 | 30 |
ELI5: How exactly does my pickle jar still smell vaguely of pickles after several trips through the washer? | Basically the way soap works is that it forms molecular bonds with a lot of sticky and food type molecules. These bonds are generally stronger than the bonds between food and skin, or food and glass. Then when you introduce hot water to the situation you're adding energy, which is used by the molecules to jump from the weaker bond to the stronger one.
So why doesn't the vinegar brine of pickles leave the glass? Because the bond with soap isn't strong enough. Dried vinegar forms a very strong bond with glass, so it has to be physically unbonded (pushed off with enough pressure) not molecularly unbonded (chemically sticking to the soap). | 32 | 43 |
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How do Ants Actually Eat? | I know that ants can suck up liquid food like sugar water and bug guts and then return to the nest to share the food through trophallaxis.
What I want to know is what ants do with the breadcrumbs and meat fragments that they drag down their anthills. How do they get the bits of bread and meat into their bodies? | You can more or less assume that insect digestive systems are the same as ours for most generalised purposes. They have mandibulae and maxillae just like we do, which break solid food up to make it fit into our digestive tract. They gave a long tube that goes from mouth to anus, they have gut bacteria, and they poop just like us. | 21 | 47 |
ELI5: Why is it when a person forces and mentally prepares him/herself to write something creative the mind is usually blank where as when he/she isnt actually thinking about it the mind is full of creativity? | When you're focusing, you're engaging the parts of your brain that handle step-by-step tasks like math. Creative efforts take specific skills to do, like drawing is a fine motor skill, but to get the ideas for that creative effort you have to use the parts of your brain that handle things like daydreaming. The daydreamy parts of your brain basically turn off when you're focused on a step-by-step type of task (unless it's a very very boring task that you've done so much you could do it with your eyes closed, like putting boxes together or folding clothes).
Basically, your brain is kind of like a computer that can do your taxes and can play video games but it can't run the video games if the taxes program is already running. | 144 | 257 |
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CMV: English speaking nations should do away with "Miss" and "Mrs.," and only use "Ms." instead. | Miss means a young or unmarried woman.
Mrs. means a married woman.
Ms. either means an older unmarried woman or can be used for any woman.
For men, they all just have Mr. regardless of age or marital status.
It is much simpler and more streamlined to just have one for all women as well: Ms.
It's sexist and demeaning to divide women by age and marital status, and has a huge potential to insult since often the speaker has to make a judgment call as to how to address a woman by assuming her age range.
Many married women idealize "Mrs." but that's only because it's something that currently comes exclusively from getting married and it makes sense that people latch onto traditions and customs pertaining to a significant life event for them. But once Miss and Mrs are eliminated and women only go by Ms, then marriage won't often come with that Miss to Mrs change that many women desire so the emotional attachment to Mrs will go away. Just because some women enjoy a sexist custom isn't justification to keep the custom. | It is a useful distinction if the married woman took her husband's last name. That way you know it is not her maiden name. Whether or not a wife should take her husband's last name is another argument, but it happens very often, so whether or not it is right has little effect on this argument.
It is also useful in dating, because it is often the man who does the asking out, and having a woman referred to as mrs. indicates that she is automatically not available.
These are a few ways that the title can exist without being sexist, because it has a functional use. | 46 | 118 |
How can we change the economic growth model in light of climate change? | Hi all, (I'm half a bottle of wine deep, don't judge pls).
My question is one of debate (at least in NZ). Economic growth is correlated to decrease in environmental conditions and more pressure on remaining ecologies and stuff.
Can the world ever get off the trajectory of economic growth, growth at all costs?
Is your country starting to lean, look and change towards one of these 3?
-Degrowth
-A growth
-Green growth?
Using Kate Raworths - Donut model as an example. Looks like its keeping economic growth, but as soon as it negatively impacts the environment, stop what that was and try something else. No matter how profitable.
In NZ it looks like its starting to take a green growth approach. The govt and others, believe in economic growth alongside environmental protection.
We introduced a new bill, the zero carbon act.
Basically;
Agriculture sector will decrease emissions (not eliminate as they are our biggest earner, and polluter lol) and everything else net zero or balanced as carbon neutral by 2050. This isnt very enforceable, much like our emissions trading scheme lol (polluter pays) which didnt work.
I wonder what climate change in terms of economics means for our consumer based attitudes, lol. I know everyone wants to have stuff, how can we satisfy them with less stuff?
Sorry, I know its many questions in one, unclear mess and such a big topic. Curious to know your thoughts x | Growth means being able to produce more with less inputs.
The idea that growth is always bad for the environment is incorrect. Technological change resulting in more agricultural output per unit of land is good for the environment, not bad for it, for example.
Things like carbon taxes are unrelated to growth and make it unprofitable to emit greenhouse gases for example. Allowing or incentivizing denser housing will free up more land. Etc. | 18 | 23 |
ELI5: Would training under increased gravity, be it strength or otherwise, be beneficial to humans once they returned to normal gravity? | I think it would be similar to training at high altitudes. That is, there would be measurable benefits for awhile, but they would quickly disappear after returning to normal conditions.
Our bodies are remarkable at acclimating to new situations, which is a double edged sword. It means we can adjust to harsher conditions like high altitude and (probably) slightly higher gravity, but then we just go right back when things get easier again.
I would also imagine that, depending on how strong the gravity increase was, prolonged exposure would have serious consequences. Imagine extra gravity pulling on all your internal organs and such, and making it harder for blood to get from your lower body back to your heart, or from your heart up to your brain. The extra exertion would eventually take a toll. | 198 | 445 |
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What are the basic questions one must ask themselves to form their own philosophy on the world, people, good and evil etc.? | I feel as though I am a forward thinking individual. As such, I find myself lying in bed at night thinking of questions that seemingly have no effect on my life or current situation. I lie awake prisoner to these questions until i have found my answer on the subject. To which, I say, there is a reason why and I believe it is to find a deep understanding of my own self and what i believe. I am no philosopher, just a man, who would like to form a basis to expand upon and excercise my right as a human to question. As this is my first post I will appreciate any and all feedback with the appropriate "upvote".
-Kilgore- | 1. What is there, really? (Metaphysics)
2. What can we know? (Epistemology)
3. How should we act? (Ethics)
All of these areas have a massive amount of literature over the past three thousand years and virtually every important philosopher can be lumped under at least one of these categories. | 13 | 15 |
ELI5: Why do some people wake up with puffy faces after a night of sleep? What is going on inside that makes this happen? | Gravity makes the fluids in your body (the ones in your blood vessels and the ones between cells, outside of your blood vessels, called interstitial fluid) to redistribute evenly through your body when you lie down. So when we're standing up most of the day most of the fluids distribute downwards, but when we lie down there technically isn't any force to promote that...
If there's enough force in the blood vessels (called hydrostatic pressure), such as when more blood rushes into them, but the diameter of the vessel stays the same, then the pressure will increase within it and promote fluids to leak out of the vessel into your tissues (becoming part of your interstitial fluid). So this makes your face swell up.
That's why people recommend putting ice packs or cold spoons on your eyes to get rid of the puffiness. It constricts blood vessels, redirecting the accumulated fluid in your tissues back to the rest of your body. | 29 | 70 |
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Why don't we always get immunity to diseases that we have had once before? | Lots of infectious diseases you can get multiple times because different strains exist, or mutate into different strains that is immune to the antibodies that worked on the earlier strain. Also some diseases like the common cold are actually caused by a bunch of different viruses that all prompt the same symptoms. | 15 | 19 |
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ELI5: the difference between 32-bit and 64-bit Windows installations, and their relation to the hardware. | Think of a computer like a great library. There are all kinds of books (storage) but also a librarian who helps figure out what books you need. The librarian has 32 assistants who help fetch books on bicycles and bring them back to the librarian. If someone comes in wanting all the books on dinosaurs, and there are 65 of such books, the books will all get there in three trips. The first trip all the assistants go out and get the books on, then go back and on the second trip they all get another book and on the third trip only one has to go and get data, but it still takes just as long, since the important thing is how long a trip takes.
So to get the books it requires three bicycle trips (but we can just call them cycles, so three cycles). However, if the librarian had 64 assistants, it would only take two cycles. There would be a dramatic speed boost, but NOT double, since there would still be on trip that only one assistant was needed, while the others are there but unable to make it go faster.
If there were 256 books on dinosaurs, then with 32 assistants it would take 8 cycles but with 64 it would only take 4. However, if there were only 20 books on dinosaurs it would make no difference if there were 32 assistants, 64 or even 128! It would still just be one cycle.
A computer works in much the same way. The computer fetches data from memory, but can only fetch so much at one time. If the computer is running at 64 bits, it can fetch 64 bits of data (and work on it) during one clock cycle. A computer running at 32 bits can only handle 32 bits of data during a clock cycle.
Well, now imagine that there were 64 assistants, but the librarian didn't know where half of them were! The librarian could only use 32 at a time, even though there were twice as many available. A 32 bit version of windows only knows how to "find" bits worth of data at a time, even though your 64 bit computer has other resources waiting that cannot be used. The 64 bit version of windows doesn't change the hardware any (of course) but it helps the hardware FIND all those assistants.
EDIT: And although this wasn't asked for, a dual core processor is like having two librarians, and the "speed" in gigahertz is how fast the bicycles can go. (Or more specifically, how long it takes them to make the trip. A 1 Ghz bicycle can make one billion trips in one second.) | 402 | 501 |
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ELI5: How do we know exactly that the bee population around the world is decreasing? How do we calculate the number of bees to begin with? | Bee keepers know how many bees they used to have, and how many bees they have now. Commercial bee keeping is a huge industry (many bee keepers rent their bees out to farmers, for example), and when commercial bee keepers, amateur bee keepers and people who plain notice bees notice colonies are collapsing, it's worth paying attention to. | 2,995 | 4,709 |
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How did humans figure what the sun is made of? | When gasses become energized, they release light at a certain wavelength. Similar to how you can use a glass prism to split white light into a rainbow, you can use a glass prism to split light into its individual wavelengths. By comparing the wavelengths of the light from the sun to wavelengths that came off of energized gas that we made on earth, we could identify that the sun was made of hydrogen. | 224 | 141 |
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evaluating a teaching demo | For those who have served on a search committee for a TT job, what criteria do you use to evaluate a candidate’s teaching demo in class? What does a strong teaching demo look like to you? Thank you. | I look for good design (appropriate length, not rushed, material flows/fits together), how likely it is to engage students (energy of the presentation, activities that help students work with or figure out parts of the content), and actual engagement with the audience (flexibility of delivery, responsiveness to points raised by the audience / questions asked, etc.).
Then there’s also the actual content coverage and how well it matches the intended level of the class and the instructions given, which is secondary to the above but important to show the candidate has a good idea of the students they would be teaching. | 27 | 28 |
ELI5: What are encryption backdoors? | I'm not sure what all the news is about and I don't really understand what backdoors are, and why the NSA wants them, or why they are bad. | Think of it like an office building, each individual has a key to their own office. Well security has a single master key that can open up all of the offices. Now the thing is when it comes to lets say an encrypted file. You are the only one that should have a key and that key if you set it up correctly should be impossible to replicate. With that in mind you should be able to trust your most sensitive data to stay secure. Well the government is saying that terrorists are using encryption to relay information about planning attacks so they need a "master key" to bypass any encryption so that they can spy on those groups. So it's like you have the key to the front door and they have their own key to your file, like a hidden back door. The main concern with this is obviously now it's not just you with a key to your most sensitive data so does someone else. People not only do not trust the government with that key but another concern is that an individual or group could possibly figure out how to use that back door and use it for malicious reasons.
TLDR; This kills your privacy. Now you gotta put all your nasty porn on a USB and actually lock it up in a safe. | 11 | 42 |
ELI5: How do we know what the Milky Way looks like? | If we're part of the Milky Way how do we know what it looks like? How do we observe a galaxy that we're part of? | Three things
1 - We understand the orbital mechanics of galaxies. We understand what shapes are possible and what are not possible due to the current laws of physics.
2 - We can look at other galaxies and see examples. For example, we see that spiral is a common shape for a galaxy.
3 - Most importantly, by looking at the stars surrounding us in the night sky, we can get an approximate picture of what the galaxy looks like. If you're on a highway and see a lot of cars in front of you and few behind you, you can estimate what the scene might look like to a helicopter even if you're on the ground yourself. Then using #1 and #2 we can match up what we see with what we expect to see and get our final picture. | 18 | 28 |
Learn C++ or Python? | First of all, I am aware of the fact that you better know both languages because they are both VERY powerful.
What language should I learn first? In my CS subject I am currently learning a lot of Java and next year C# and other languages will come too. But I want to start learning another language on my own. What is your opinion on both languages? Which one should I choose? | I would learn C++ first so you can understand things at a lower level which will translate into being a better and more efficient programmer in Python. Just to name a simple example, you’ll understand why `obtect1==object2` evaluates to false in Python although both objects contain the same exact property and values because you would have dealt with pointers in C++. | 17 | 25 |
[DC] Does The Flash always need to re-set his watch? | He regularly reaches relativistic speeds, which should make time pass more slowly for him than the rest of the world. If he's wearing a watch, it would appear to be slow (ironically). | Maintaining temporal relativity seems to be one of the benefits of the Speed Force for speedsters. The most interesting thing is it seems to be an at will thing, or relative to their rate of speed. There have been some instances of speedsters exceeding this and aging to death within seconds, but it's far more rare than one would expect.
Given this, they should only have to keep track of timezones like the rest of us, as long as they don't exceed the Speed Force's protective abilities. | 26 | 53 |
ELI5: Why is it that Iron is the worst element to a star? Why is it that it causes the end of a star? | Elements can be divided into two categories. The first category contains elements that require outside energy to push together (fusion) and give off energy when they split apart (fission). The second category is the reverse, giving off energy when they fuse, and requiring extra energy to sustain fission.
Heavier elements, like plutonium, tend to be in that first group. Lighter elements, like hydrogen are in the second. The dividing line falls roughly at Iron.
Since stars are basically giant fusion reactors in space, they can run on everything fusion produces, up to Iron. After Iron, they aren't getting enough out of the fusion to keep the cycle going. And so the reaction stops. | 15 | 15 |
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ELI5: Why is that foods have to be eaten at a certain temperature to have "good taste"? Why does temperature affect our taste buds? | Food is tasted because of chemical interactions in our taste buds and works in concert with our sense of smell; smell is critically important to taste. If you can't smell, you really can't taste very well.
"Heat" is simply a measurement of energy in chemicals, so when things are hotter the chemicals in them are moving around more, and more volatile. They interact better with our taste buds and also diffuse better into air, allowing us to smell them more readily.
This leads to the flavour being much stronger in hot foods than in cold.
So depending on the food, the amount you want to taste it will determine the ideal temperature. That's why bad beer has to be served cold, for example, because you don't want to actually taste it.
Whereas good beer is served at room temperature, because it allows you to actually taste it. | 17 | 32 |
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ELI5: Why is Social Security "running out" ? | I keep hearing that Social Security is running out and people of my generation wont see any penny of the money we are paying now. If this is true, why? And further, how come Social Security is at danger of running out but other welfare systems are not? | The social security is funded by payroll tax, for the benefit of mainly retirees. Problem is that the population of the United States (and pretty much all developed countries) is aging, and the pool of people paying the payroll tax is decreasing while that of the aging dependents are rising. ATM it is predicted that at its current rate social security will be exhausted in 2033, but it's not hard to solve that problem. Increase the taxes, upping the age at which people can start collecting benefits (logical now that people are retiring older), allow immigration so that more people will pay......... but some are only interested in cutting the benefits. | 18 | 28 |
CMV: Organized religion is harmful to human society | Organized religion, specifically the main three monotheistic religions (Christianity, Islam, and Judaism) cause more harm than good to human society and individual people.
Religion causes conflict between people. Almost everyone would agree that conflict is bad, since it causes physical and psychological harm to people. Conflict is more likely to occur when there are organized groups of people, or “tribes.” This is because each group has a cause they are fighting for, and people they are fighting against. In the case of religion, this is very evident as people in each religion would fight for their God, and would fight against other religions or against non religious people.
(For the previous point, it is talking more about modern day mistrust between religious and non religious people, not ancient wars)
Religion is based on non substantial evidence. Religious texts outline events which are not supported by our current understanding of the universe. These include the events of creation, various “miracles” performed by a divine being, and contemporary interaction between God and followers, such as through prayer. Although depending on who you ask and what their interpretations of the religious text is, some of these problems may be resolved as being merely metaphorical statements, many people also choose a more literal interpretation. Almost every seriously religious person would believe something that is at least partially contradictory to what has been proven to be possible, or is plausible given our current knowledge.
Given that religion accepts statements as knowledge despite them not being able to be proven, this will negatively affect the future choices made by people. One of the most fundamental differences between knowledge with proof and knowledge without proof is that the knowledge without proof is a lot more resistant to change. Think about someone challenging a scientific theory, and comparing it to someone challenging the existence of God. Since our knowledge affects the choices we make, and knowledge that is closer to the truth will cause people to make better choices, it would be better to allow for positive change (as in non religion), as opposed to not allowing positive change (as in religion).
Although there are some positive effects of religion, such as trying to balance wealth between people (such as through charities), the negative effects far outweigh the positive ones.
CMV | > Conflict is more likely to occur when there are organized groups of people, or “tribes.” This is because each group has a cause they are fighting for, and people they are fighting against
There’s a fun South Park episode where humanity recognizes the foolishness of religion and it’s abolished, only for humanity (and talking otters) to end up with three sects of atheism fighting over the one true form of atheism. While patently absurd, it highlights the natural tendency for humans to subdivide into tribes and fight each other. Religion is hardly the only way that we do that. Nationalism, party affiliation, sports team fandom...there are many different axis on which a lot of us pick or are assigned a side and slowly begin to dislike/hate those not aligned with our choice/side.
So the important question for you is, what makes you believe that, absent religion, we wouldn’t find some other way to subdivide ourselves into tribes which ends up just as damaging as religion is currently? Obviously, if we could all figure out how to live together harmoniously, it would be better, but what makes you think that’s at all possible for our species when the evidence seems to point to it being in our nature to divide ourselves into trusted/other groupings? | 57 | 161 |
[Star Trek] If Picard didn't specify the kind of tea, would it have been different? | I imagine the replicators would remember a person's personal preferences, but I am unsure.
To clarify:
"Tea. Earl Grey. Hot." = hot earl grey tea.
Would "Tea. Earl Grey." Produce a cup of tepid earl grey? | The computer usually asks the user to specify if a needed argument isn't given. General syntax would be:
>User: Tea.
>
>Computer: Please specify type.
>
>User: Earl Grey.
>
>Computer: Please specify temperature.
>
>User: Hot.
We can assume that the 'hot' argument is a preset value, vs stating the exact temperature desired, presumably based on user metrics. This is not always the case with replicators, especially those that have been brought online recently. The replicators on Voyager were notoriously user-unfriendly in the beginning. | 26 | 16 |
ELI5: Would health or body weight outcomes differ if you: a) Eat one slice of pie every day, year round, or b) eat 7 slices of pie on one day each week, every week, year round. | Would the same be true for alcohol? Is regular consumption of unhealthy food/drink better or worse than periodic bingeing, holding average consumption amount equal?
Had to look up spelling of bingeing/binging. Seems they're both acceptable. | Nutrition wise: It would be different, because your body adjusts based on how much it needs to work at the time. But that said, the difference would be so small it may not even be worth paying attention to.
Dental: Well, yeah, because you're exposing your teeth to the sugar 7 days a week rather than just one. | 21 | 38 |
CMV: "White privilege" gives nowhere near the advantages as money, family status and connections do. | I don't deny that being a minority gives people some disadvantages and that there are still stereotypes and discrimination floating around. However, in recent times we have really done a lot to battle those things and I think people in America for the most part don't discriminate based on race.
What I think is really going on when people spout about"white privilege" is the middle class and up that has more money, more status and more connections that make life a whole lot easier.
I really don't think you'd find a significant difference in advantages between an upper middle class white family and an upper middle class black family.
In my opinion, people only say white privilege because the middle class is mostly white. In America, minority communities are usually poor and live in inner cities. That itself is a huge problem and has been a problem forever.
I think that if a white person grew in a poor inner city neighborhood, they would have hardly any, if at all, advantages over a black person in that same area.
I believe the real problem is wealth and connections and not skin color. I also think this talk of white privilege just misses the point and doesn't address the real problem of income inequality.
Edit: I changed my view and am no longer responding to comments. | Generational effects have actually made it so those three things (money, family status, and connections) are all quite concentrated in the white demographic. What you're talking about mostly affects competition *among* white people, but the average white person is better off in all three areas than other groups, this fact is itself *part of* white privilege. This is not changed by the fact that white people don't all have equal amounts of privilege in every area, nor that not every single white person has more of them than every single black person. You're correct that income inequality is a big problem, and the source of many other problems, but are missing the fact that income inequality is itself one of the vectors along which racial inequality makes itself apparent as well. | 542 | 1,340 |
ELI5: when people do coke in movies, what are they actually sniffing? | Lots of different recipes. For snorting they use powdered lactose, or a vitamin b power if there are lactose intolerance issues. Also, if the actor is using a straw or something to snort it, they will coat the inside with Vaseline so very little will actually go in the nose. Snorting anything will cause congestion. | 121 | 108 |
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ELI5: what is visa? (not the credit card) | Context: I want to ride the bike from Austria to Australia. 35.000km. 365 days. Obviously, I have to cross a certain amount of countries between. (More infos on austria2australia.com/)
So: what is a visa? I was born with Schengen, I never had to apply for a visa, and the whole concept of it is strange to me. I honestly have no glue about visa.
| A Visa is a document giving you permission to enter another country. Some countries require that you get permission before entering. They offer different types of Visas, depending on how long you are staying and for what purpose. You will usually need to visit that Country's embassy in your nation to fill out the application and in most cases pay a fee to get the permission to enter. | 16 | 20 |
[Star Trek] Why are Star Fleet computers so complex to operate? | Every time a crew member uses a Starfleet computer to do anything it takes a lot of button presses, sometimes striking the same button several times. Why so complex? It just seems inefficient | Remember that Starfleet computers need to be operated by multiple species, sometimes with very different bodies or manipulating digits. They need to be as universal as possible and as comprehensive as possible while still being functional.
Often, when you see someone press multiple buttons, they're actually inputting calculations for specific systems so the computer can automatically follow through. On navigation consoles, the pilot will put in spatial coordinates, ordered speed and any known obstacles for the ship to avoid. A weapons officer will put in weapon types, yield and targeting information. Doctors need to look up appropriate medicines in a menu, create a dosage and a safe delivery method. (I doubt hyposprays "spray" at the same velocity for every species and individual) Engineers... put in a lot of things.
Pressing the same button could be multiple "confirm" commands. Or maybe going back to a menu to open up another set of options to fill out the desired comands. | 75 | 29 |
Why are light blocked by walls but radio waves are not even though they are both electromagnetic radiation? | One of the ways to think of light is as an individual little "chunk" of light. Imagine that your class goes on a field trip to the amusement park. You're walking around together, and then you pass the entrance to the Ferris wheel. There's a problem, though, a sign says you have to be at least 4 feet tall to ride on the Ferris wheel. Your tall friends all go on the ride, but you and the other kids have to keep walking through the park. Later, you guys might pass by one of the kiddie rides, and that says you have to be UNDER 4 feet tall to ride, so now you get to go on that ride, while your tall friends keep going.
That's the way light works when it goes through stuff. All of your friends are like little pieces of light. Just like not all of your friends are the same height, not all pieces of light are the same color. When it passes through a material, if it's not too tall or too short, it gets 'absorbed,' but if it's unlucky, it might go through the whole park without ever finding a ride that it is allowed to go on. If that happens, then the light passes right through, like it does in glass or water, or like how radio waves (very very tall guys) go through walls. | 97 | 120 |
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[DC/Marvel] When you sit down for your first day in a physics class, what does the teacher tell you about the value or truth of what you will be learning? | And I'm not talking some special genius institute run by secret agencies or one of the world's smartest men. Just a regular physics/science class at a regular college teaching normal people how to be the electrical engineers or nuclear physicists of tomorrow. I mean, teaching out of the same old physics textbooks must be a tough gig. You can play the "Thor's an alien, not a god" card at first, but there are guys running around like Dr. Fate, Zauriel, Mr. Mxyzptlk, Scarlet Witch — public figures battling on national TV whose very existence calls the basic foundations of science into question.
How do regular teachers answer those kind of questions and objections from regular students? | You know how, sometimes in high school, if you ask a question that's too advanced for your teacher to answer, then he or she will say something like, "That's not something we can cover in this class, but if you're interested in it you can research it on your own, or maybe even major in it in college"? Sort of like if you tried to ask a question about the equations that prove general relativity in a basic physics class. Your teacher would probably be impressed with your knowledge and initiative, but would not be able to cover the topic to a sufficient level of depth or rigor in a high school physics lesson. Heck, your physics teacher might not even know enough about the math behind general relativity to give you the answer you need.
Similar idea. Physics classes in the Marvel or DC universe would cover the fundamental rules of physics, like mechanics and optics and electromagnetism and thermodynamics. But some kid raises his hand and asks, "But what about Dr. Strange, he can make fire spout from his hands. Doesn't that violate conservation of energy?" And the teacher would reply, "That's a good question, but it's not something we can cover in this class. If you're interested in knowing more, you can research it on your own, or maybe even seek out the Ancient One and ask him." | 75 | 64 |
ELI5: Why does water make some things slippery while also making other things more grippy? | When your hands are wet, it can make gripping things more challenging, like your feet on a pool deck or your tires on the road, right?. Climbers use chalk on their hands to get rid of moisture/better grip. So why does licking your fingers make it easier to count money or separate plastic bags (sticky)?
I’m aware of the terms cohesion and adhesion in regards to water particles themselves but how does that apply to both the slippery aspect and sticky (for lack of a better word) of water against non-water things? | It depends on both the materials of the objects in contact and the amount of force being applied. With the paper and grocery bag examples, there is little force and lots of adhesion. Paper and plastic bags are very porous on a micro level, giving the water lots of surface to 'stick' with. Adhesion with water, though, is not strong enough to hold a climber. The force of holding up a human body is too great. The water molecules instead slide around each other and the surfaces, reducing friction. This is not what you want when clinging to a cliff. | 11 | 26 |
Which IR theories are the most popular today? Which contemporary IR theorists are the most cited? | I live and study in Poland and I can't help but think that the curriculums in our universities are a bit outdated when it comes to international relations theory. Even the university libraries don't really have anything newer than 2000 or if they do, it is just a reiteration of the works from the 20th century. It is difficult to learn which are the most dominants theories/paradigms/schools in the second decade of the 21st century and which currently living scholars contribute the most to the discipline.
Can anybody fill this gap for me? Where should one look when trying to analyse the current status of IR? | Your main three are probably Realism, Institutionalism (Liberalism), and Critical theory. None of these are particularly new, but critical theory is the most recent. All of these were mainly developed by 2000 so you should be able to find some information on them.
Foreign policy ideas of course are always changing in the contemporary. You could check out the most recent pop-theory “Why Nations Fail”. It was a great read. | 11 | 32 |
ELI5 Why does diarrhea come so quickly when food takes hours for the stomach to digest and days to pass through the intestines? | I had Mexican tonight and had to rush to the toilet after a hour. Did I expell the burrito? What about the pasta I had for lunch, or the omelette I had for breakfast? Did they all came out without my body absorbing their nutrients?
Edit: Front page? Whoa. I guess diarrhea is more than meets the (butt) eye.
There seems to be two school of thoughts here: (1) the diarrhea is caused by the burrito, and (2) it is caused by something I ate the day before. | So your bowels are like a long train track and your food is like a set of cars on the track. Transit time between Point A, your mouth, and Point B, the chute, is a bit flexible but normally operates on a regularly scheduled basis.
When you eat, you put cars on the track and send them to Point B. As these cars go to Point B, they lose passengers (nutrients) at various points in the thin tunnel portion (small intestine). The journey isnt complete and the journey has already altered the shape of the car pretty significantly giving a rusty color. Once in the larger portion of the tunnel, the cars are checked for stray passengers and are hosed down a bit so that transition out of Point B isn't so bad. Sometimes, the train cars park juuust outside the gates of Point B so they can exit at the best time for the operator (toilet).
Now, all of this goes fucking nuts when you load a bad set of train cars at Point A. The track sensors located everywhere along the track, detect this alien set of cars and sends a distress call to the Supervisor (your brain). The Supervisor wants to handle the situation without having to phone the Manager (your consciousness) about the craziness on the tracks and also wants to make sure you never know it was on the tracks. It has to make a choice now: send it back to Point A violently and somewhat painfully risking tearing the tracks, or send it to Point B as fast as fuck? Depending on where it's located on the track, it'll choose the best route.
Let's use the destination Point B. The Supervisor hits the panic button and puts all the train cars that are on the track (in your body) on overdrive. The tunnels are flooded with water and lubricant to speed all the cars up and get them the hell out of there as quickly as possible. Cars collide with each other, and previously well formed cars are just flooded with water and lubricant that they are just a soggy, shadowy reminder of their former glory state.
The Media (pain) hears about the car collisions immediately begins filming live the high speed, flooded train cars out of control. They want to knos how an alien set of train cars were put on the tracks and they want someone to pay for such carelessness. The Manager is just watching the horror unfold on Live TV but cannot do anything to stop it, because the Supervisor was deaf and he had not installed a means of communicating with him after hours in the office.
I hope this answers your question.
TL;DR when you get diarrhea, everything gets pushed out, one way or another. There are no passing lanes.
Source: medical student
Edit: Wow, thanks for the gold!! | 5,359 | 4,205 |
CMV: The "Model Minority" and "Positive" Asian Stereotypes are Dangerous and Racist | People don’t believe Asian stereotypes are harmful. We are the “model minority” and how can stereotypes be harmful when these stereotypes are “positive?” All my childhood, I have been bombarded with unrealistic expectations of being quiet, demure, and smart. I felt like if I didn’t live up to these standards that I was a failure. I was supposed to be good at math, ace every test, and know every answer. All my achievements were attributed to my racial status rather than praised as evidence of my hard work.
It was even worse when I started puberty and engaged in social media platforms. The hyper sexualization and fetishization of Asian women in media was appalling. Media had created the image of the Asian woman as passive, submissive, and flat; in addition, the lack of Asian female representation perpetuated this stereotype due to ignorance. It equated Asian women to the epitome of feminine women who praised the patriarchy. We are “exotic” in the eyes of Western media.
So how can Asian stereotypes not be harmful when it creates a toxic mindset and perpetuates the sexual objectification of an entire race?
Edit: I am an Asian woman.
_____
> *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!* | I would say it's an intermediate stage to attaining full equality and hence, a means, and not the end goal.
In general, prejudice against a new group (race, gender, religion, sexual orientation etc.) follows four phases, each being progressively better than the last.
Fear and aggression ---> Comic and Stereotype of Inferiority ---> Positive Stereotype (Cool) and Fetishing ---> Equality.
In case of black people, the pattern can be reflected as
Savage animals raping white women ---> Bumbling servants who are hillariously stupid ---> The "cool" black friend who'll give you advice and solve all your problems ----> Equality and Respect
In case of homosexuality, it is -
Perverted Freaks who are Rapists and Molesters ---> Funny Freaks with womanly accents and made fun of (gay jokes) ---> The "gay friend" who'll help you shopping and accessorizing and give relationship advice ----> Equality and respect
In case of Asians, it is :
Freaky Japs, who eat dogs and torture people in creative ways ---> Funny simplistic idiots who get confused by English ----> genetically intelligent people, good at math, electronics and technology ---> Equality and acceptance | 10 | 35 |
ELI5: What's the difference between one day (single use) contact lenses and regular lenses? | What makes the single uses lenses single use. Why can they not be used multiple times like other contact lenses? | One day lenses are much thinner and less durable, however since you wear a new pair every day they're usually more sanitary, can't develop buildup that can scratch your eyes, and generally easier for the wearer.
Biweeklys and monthlys are much sturdier, but degrade over the lifespan of the lens. They also require a lot more care than daylies. You're supposed to rinse them for 5 seconds on each side with solution and let them sit in the contact solution for 8 hours, which can be a lot of work. Most people I've heard don't rinse their contacts, just soak them.
Also, everyone's eyes work differently - some people can use the biweeklys for over a month, while other people's contacts degrade quicker. This can lead to either just living with worse eyesight or quicker replacement. Wearing contacts longer than their recommended use period can cause microscratches on the cornea from tiny amounts of buildup. It can be done, of course, but it isn't great for the eye. | 14 | 43 |
Advice For Humanities Scholars Thinking of Leaving The Academic Industry | I wanted to offer advice to professors or PhD students who are considering a career change. Last year I resigned from my tenure-track job in English, my first full-time academic post after graduate school. Ten months ago I began a new career in hospital operations management, a field in which I had no previous experience. The work is stimulating, challenging, and well compensated.
My post is mainly intended for Humanities scholars as I am most familiar with that discipline. I am not offering (or selling) services of any kind, just some ideas I've picked up over the past year.
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**Volunteer For More Work Experience**
If you are fortunate enough to have a tenure-track appointment it counts as one entry on your resume. You can include one bullet point for teaching, another for research, and a third for administrative work, which in my experience was the main focus for/of employers. This is the complete entry for teaching on my standard resume:
> “Developed and taught 18 courses over 8 years; translated complex topics and coached foundational skills; conducted qualitative and quantitative feedback to improve self- and participant performance.”
Eight years of my working life – all of my successes in the classroom, the late-night grading sessions, untold hours developing my lecture notes and materials – over two adjunct positions and one tenure-track appointment is condensed into three clauses. You may add another bullet point for your editorial responsibilities at a journal or your leadership of a working group or program, but many early-career academics do not have those experiences.
You will need additional, non-academic work entries on your resume to be competitive for most non-academic jobs. Perhaps the best method if you still work in academia is volunteer work. If you do not have a specific industry already in mind I recommend two options:
* Write grant applications for local non-profit organizations. You will likely already have strong writing skills and understand how to follow grant application instructions. There are many charitable funding opportunities that go unused. Email the director of a non-profit organization whose mission you support, explain your commitment to their cause, and offer your services.
* Serve on the board of directors of a local non-profit organization. You will likely already have strong organizational skills and can hold the attention of a room. Research the organizations in your area that are run by volunteer boards: civic organizations, charities, co-ops, condos... you should volunteer with the organization first to determine whether their general leadership structure is sound, but unless you observe any serious problems it is relatively easy to get elected to these positions.
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**PhD Students/Adjuncts: Consider Working For a Staffing/Temp Agency**
My hospital uses a staffing agency and short-term contracts for, among other reasons, the chance to evaluate promising employees for long-term positions. After talking to colleagues in other industries I learned this practice is fairly common. Some staffing agencies specialize in a particular industry, while others may have experience working with highly-educated candidates like you. Most recruiters work with rosters of managers who require certain kinds of staff. They do not benefit from sending unqualified staff to their customers (i.e. people like me), which means they can help you to identify your strengths and expose you to a range of *relevant* non-academic opportunities.
I hire temporary staff for short-term entry-level clerical and research positions; usually BAs and MAs without much work experience. They make considerably more money than adjunct professors and do not work nights or weekends. They also parlay temporary placements into full-time positions at the hospital or, even if a placement is not successful, they gain valuable work experience. I was originally hired on a temporary contract as a researcher with no previous experience or contacts in my industry; a few months later they hired me to manage my own program, as well as a few others. You can do this too!
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**Learn/Teach Yourself Key Skills**
Before leaving the academic profession, I came across many articles in *The Chronicle* and elsewhere that advised readers to identify ‘transferable skills’ that can be re-purposed for non-academic contexts. These skills do exist; for example, many academics in the Humanities can write for multiple audiences (students vs. colleagues) and know how to navigate complex bureaucracies. However, you should also consider learning more about the programs, applications, and/or skills that are valued in the industries in which you want to work.
For example, one of the most highly-valued skills you can learn for an office-based or management role is expertise in MS Excel. Almost everyone claims on their resumes to know the MS Office suite, yet very few entry-level job candidates seem to understand conditional formatting or how to use pivot tables, much less the more advanced features in Excel. Do you know them?
One way to learn Excel: download a numbers-based data set relevant to your own academic research: census data on a community you study, sales figures in the literary genre in which you specialize, etc. Look for free online courses through educational organizations like Khan Academy, or check with your institutional or municipal library for a subscription to services like Lynda (now LinkedIn Learning). Spend one hour each day taking an Excel lesson using your specific data set. You can simultaneously develop your Excel skills and also produce material for your next research article or lecture notes.
Do not go back to school for another degree.
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**Practice Writing Your Resume Now**
Writing a post-academic resume is surprisingly difficult if your only recent experience is in writing or updating an academic CV. As an exercise: visit a job search engine with listings in your community, choose a listing that appeals to you, and attempt to write a 1-page resume for that job. How do you demonstrate that your past or current work experience is relevant to the position? What are your marketable skills? How do you convince an employer that you could do the job? Stylistic conventions for the academic CV are standard across the industry, with slight differences in what matters most depending on your field or department. There is no universal standard for resumes, other than a typical 1-2 page limit. You should practice writing resumes using real job listings for at least a month or two before you go on the job market.
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I hope these bits of advice are helpful to those of you thinking about a career change, but unsure where to begin. I don't plan to write about the academic-to-non-academic career transition ever again, but I would be happy to answer any questions you have about leaving academia, job searches, etc. Just leave a reply!
([cross-posted](https://www.reddit.com/r/Professors/comments/fqpoce/advice_for_humanities_scholars_thinking_of/) to r/professors) | +1 on the advice to apply for local grants. Most scholars are completely oblivious when it comes to where pots of money are. Everyone is going after NEH, MacArthur...sure, apply to one of those once but then repurpose that application for the family or community foundations in your area. You might only be getting $10k after overhead, but you get to hire a couple students for a semester, or do some major summer travel, or pair it with other funds.
And fwiw, your school probably has a subscription to fdonline.foundationcenter.org (edit: fixed URL). It takes all of ten minutes to find lesser known foundations that are interested in your work...and a lot of those small ones are happy to hear from you directly, by phone or email, and'll sometimes just say "Your project sounds great. The application will just be pro forma."
Big piece of advice though is to research their 990 tax forms. You'll see who they've given grants to in the past, and for how much. In the case of family foundations, sometimes you need to do that in order to weed out politically sketchy families. You'll have people that are wonderful arts benefactors who also, like, fund bonkers think-tanks. | 27 | 220 |
CMV: New York City should abolish rent regulations. | NYC currently has two schemes for limiting rent: rent control, and rent stabilization. Both of them should be abolished, though gradually. I would propose that currently controlled units remain controlled, but that:
* Current units cannot be transferred to a new tenant. If the original tenant on the lease at the time of the decontrol law vacates the unit, the unit can be listed by the landlord at market rates. Currently, other occupants related to the lessor can inherit the lease, meaning units pass down in families indefinitely.
* Newly constructed or rented units are not subject to any controls.
* Rents in all controlled units can rise by up to 5% per year.
* Rent decontrol be coupled with large scale upzoning to allow more housing to come on to the market. This will include infill construction in NYCHA housing projects where developers are willing to pay market rates for the land.
* Buildings which received Mitchell-Lama or other tax subsidies must pay back the subsidies with interest before decontrolling units which were built as a condition of the subsidy, on a pro-rated basis.
The reason I want to abolish rent regulations in NYC is that it drastically reduces the available housing supply and harms people looking to move to or within the city. Anyone who has won the rent regulation lottery never moves out, and you end up with a highly inefficient allocation of apartments within the city.
It also hugely depresses the creation of new rental units within the city, because new landlords see what happened to old landlords who got stuck with controlled units.
I don't think there should be a property right in a rental. If you want a property interest in the place where you live, you should buy it. If you're renting, you should be subject to the market forces that come with that.
**Edit 1:** I was hoping to get some replies before I had to step away, but so far it's just crickets. Will be away from computer for about an hour and a half or so, and will reply when I'm back.
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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!* | You can find reams of papers back and forth about the positives and negatives of rent control. In general, economists prefer market driven pricing while social activists and minority rights activists tend to prefer rent control.
The strongest argument for rent control I've heard is that it provides housing price stability for long term residents - If someone is lower income and/or fixed income, they could easily be forced out of their apartment in an appreciating housing market. Since moving costs and security deposits are a lump sum cost that many can't afford, it can be very harmful for these people to have to move regularly, and continually have to relocate to further away and/or less nice neighborhoods. This tends to disproportionately hurt elderly, poor, and minorities, and benefits landlords and property owners. | 133 | 279 |
ELI5: What is acid, and how can it "burn" things into almost nothing? | My knowledge of acids are very limited: All i really know, is that it has to do with the value of the PH-scale. | Acids are compounds that provide hydrogen ions when in solution. Since a hydrogen molecule is just a proton plus an electron, a hydrogen ion is really just a proton.
These unattached protons are like groupies backstage at a rock concert, willing to make attachments with anything they encounter, whether they were previously attached or not. If you have enough of them, especially in high concentration, they will break down existing substances as they destroy the molecular bonds in those substances.
They don't turn other substances into "nothing"; they just produce what are usually soluble salts, as opposed to the solids that were there before. So, like the Wicked Witch of the West, those solids turn into liquid and melt away.
| 54 | 15 |
Are there more than 2 solutions to the grandfather paradox? | It seems like the only two solutions that I've ever heard are that either you can't kill your grandfather no matter how hard you try or the universe splits into alternate timelines. Are there any other possible solutions? | What would you consider the criteria for a solution? Currently I’m in a graduate seminar on Time Travel and metaphysics. Most of the literature in defense of TT turns on trying to show that there is no paradox here at all. Are these solutions?
I am currently working on a paper which is meant to explain certain objections to Time Travel which are considered “inexplicable”. | 32 | 56 |
Why can't quartz be grown epitaxially? | Ceramic engineer here - it can be grown epitaxially, but generally if you try to deposit silica onto a substrate that isn't quartz or something with a very similar structure it's deposited as amorphous silica rather than one of the crystalline forms of quartz.
| 29 | 170 |
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ELI5 what happens with spit once you swallow it. | The vast majority is water which will recycle back into your bloodstream and lymph system where it will either be used or excreted. The small remainder which is protein, enzymes, salts, etc will either be digested and reused or excreted. | 36 | 37 |
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ELI5: Why the US congress is trying to class pizza a vegetable | I've only seen the odd joke about it here and there, what are they actually doing it for? Is it in the interests of the pizza industry or something? &#3232;\-&#3232; | Food in school has to meet various nutritional requirements. It had to include like 1 serving of veg, 1 serving of protein or whatever.
It was lobbied by the food manufactures that the tomato paste used as sauce on school pizzas should be considered a vegetable.
It ends up being more cost effective, although obviously not better for the students. | 317 | 319 |
CMV: Jury nullification should be a respected right. | Jury nullification is when the jury acquits someone because they feel that the laws used to convict them are unjust, or are being unfairly applied. I think it should be a right that's more publicly known, that courts can't restrict the doing or awareness of, and that jurors feel more comfortable using. I think it could help significantly in cases where jurors feel that a law is being used for racial profiling, for needless incarceration, such as drug convictions, and that it would do more good than harm to let juries overturn the law when they find it to be wrong.
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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!* | There are two ways legal consequences could be doled out, the rule of law, or personal discretion.
They both have some strengths and drawbacks, but on the whole, discretion is scarier, and we ought to be pretty thoughtful where we allow the rule of law to be pushed back.
When you have rule of law, you have predictability, you have transparency, you have broad community input. When you work from discretion, you take all that power and you make it unpredictable (You don't know how a small group will act with their discretion) you make it opaque (There is no clear system, the reasons can be easily hidden) and maybe most importantly, you take away power from the broader community and put it in a small handful of people.
Of course bad laws can be made, but we have checks against that in our current system. Legislators can be unseated by election, they can only pass laws with a majority, which requires the support of a lot of people. We have a constitutional system, both on a state and federal level. Certain freedoms are enshrined in the constitution and can only be changed by a massive majority.
Yes, we've had some bad laws, some racist and sexist and dumb laws. But without rule of law, how racist and sexist and dumb legal consequences may be would vary by whim. | 17 | 57 |
What are the best contemporary defences of liberalism against Marxist critiques? | At least in what I've studied, post Rawls there seems to be a basic acceptance of at least a modest liberal framework in contemporary analytic political theory, even from philosophers pretty far to the left (e.g. Otsuka or even Cohen).
I'm looking for the best contemporary works/philosophers that defend this assumption against the more traditional Marxist critiques that wholly reject that framework (others welcome too). Thanks! | A lot of the contemporary defense of post-Rawls liberalism centers around Marx’s critique of justice. You may want to look into Allen Buchanan’s *Marx and Justice: The Radical Critique of Liberalism*, as well as Will Kymlicka’s *Liberalism, Community, and Culture*, which defends liberalism against both communitarian critiques and Marxian critiques (see especially chapter 6 on “Marxism and the Critique of Justice”). Another book worth reading is Steven Lukes’ excellent *Marxism and Morality*, which analyzes and assesses Marx’s critiques of morality and *Recht*. | 20 | 31 |
If the sun disappeared, just vanished, would we be able to tell something has happened before it all goes dark? | If some weird cosmic event made the sun disappear, presumably, it would take 8 minutes before the lights went out on Earth. However, are there other effects we would notice before the lack of sunlight became apparent, for instance, how quickly would the Earth hurtle into space on a tangent to our normal orbit. | According to general relativity, gravity also propagates at the speed of light, as does any other information we could measure about the Sun. Unless we had some way of detecting the event that was about to cause the sun to disappear, we wouldn't notice it until 8 minutes later. | 39 | 30 |
Can one be a good person and be happy while others are suffering? | I am wondering how/if it is possible to be happy if one knows that people in the world are suffering. For example, how can a globally conscious person be happy if there are many people suffering due to mistreatment, war, poverty, etc. Is it possible to care about those people yet still be happy? | Notice what happens if at least one of the following is true:
- **P1**: It is not possible to be a good person while others suffer
- **P2**: It is not possible to be happy while others suffer
- **P3**: It is not possible to be happy and good while others suffer
Depending on which proposition you say is true, in any case it seems to destroy the possibility of there being good people, happy people, or good & happy people, since human suffering is quite widespread.
On the other hand, we can modify what was said to one of the following, which is probably what OP is after:
- **P1**\*: It is not possible for X to be a good person while X knows that others suffer
- **P2**\*: It is not possible for X to be a happy while X knows that others suffer
- **P3**\*: It is not possible for X to be happy and good while X knows that others suffer
Depending on what we select as true, good, happy, or good & happy people must be ignorant of suffering. This says nothing about whether there is suffering, just about what information X has.
Do any of these sound convincing requirements for goodness or happiness?
Edit: I've added a third conjunctive expression and edited the wording thanks to /u/mrken71's comment
| 22 | 37 |
ELI5: Why do college applications and job applications even ask for your race, ethnicity and gender? Wouldn't it be more fair to screen applicants without that knowledge? | For colleges there are scholarships and grants that are limited to specific races, ethnicities, and genders.
For both jobs and colleges they need to know that information for legal purposes in case they get sued for discrimination in the future. | 35 | 70 |
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What keeps tree roots from rotting under ground? | Rot happens when dead tissue gets consumed by bacteria and fungi. Living organisms don't rot because they have immune systems to protect them.
The immune system of a plant doesn't work the same way ours does. It tends to be a lot more passive. Instead of having special cells seek out and destroy invaders, it tends to secrete chemicals that either harm the invading microbes or else block them from spreading. But that simpler system still usually achieves the goal, of making sure microbes can't eat it alive. | 14 | 18 |
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Why dont we kill HIV/ AIDS by killing the immune system? | Alright so I was prepping a lesson for class, where I need to cover HIV in the work place.
My question is, since the virus cannot survive without attaching to and replicating through a cell(specifically for HIV,cells with the CD4 molecule) why do we not just use a process such as chemotherapy to kill the cells, stick the patient in a clean room for however long it takes for the virus to die and then restart the immune system through bone-marrow transplants or something that might actually work.
It might be like taking a butchers knife to the patient, I'm just curious if this has been looked into.
Forgive me if this is a dumb question, its definitely not my field. | This has been done a couple times, coincidentally, in people with both HIV and cancer who received a bone marrow transplant, but it is very risky and the donor has to be a very specific and exact match. To kill off someone’s immune system and form a new one is a huge task and many would not even survive the process. The side effects of medications used for this take an enormous toll on the body, and significantly increase the risk of cancer later in life. In many cases, this treatment would be more deadly than living with treated HIV. | 119 | 31 |
Does Thomas Nagel believe there is no evidence for an external world? | https://wmpeople.wm.edu/asset/index/cvance/nagelskepticism
I was reading this excerpt and from the reading it sounds like Nagel thinks of the problem of the external world to be an unsolvable one.
While most philosophers would say that although unsolvable, it is the best explanation that the world is external and beyond our own minds. However, Nagel never mentions anything of the sort, instead saying that we are programmed to believe in an external world wether or not it is actually true. If Nagel is correct, does that mean that we are effectively giving the shrug to the question of metaphysical solipsism, saying “it could go either way” with no justification for each? In other words, 50/50. | As he says on page two, Nagel does not intend to argue that scepticism about the external world is the right picture: he thinks that there is an external world beyond ones own experiences and that in at least some fashion one’s experiences reflect that external reality.
He isn’t going for the 50/50, he is all in for external reality, he just doesn’t think that a sort of ‘traditional’ empiricism can give the final determination about what is and is not “conscious” or “minded”.
Remember that in these short eight pages Nagel is only trying to motivate an interesting question about the nature of consciousness and the problem of other minds: he’s not giving his final thesis or the arguments for it, and he will go on *later* in the book to attempt to give what he considers better explanations for what minds or consciousness or whatever *actually* are. | 40 | 69 |
When I brush my teeth, what's more important—the brushing or the toothpaste? | Which would leave my teeth better off: brushing my teeth with no toothpaste for a year or putting toothpaste on my teeth for a year without brushing? | Brushing the important part, the mechanical action of the bristles break up the biofilm created by bacteria, loosening up the bacteria so they can be rinsed out and of course clears out food residue that may be stuck in crevices.
If you go without brushing, but just gargle with toothpaste and regular mouth wash you will get substantial buildups of bacteria which cause decoloration, plaque buildup, gingivitis and cavities. Your gums will be very vulnerable as you have no way to clean the crevace between your teeth and gums.
Brushing with just water is very effective, although flouridation has been shown to help as it can kill residual bacteria left after brushing and rinsing.
Many animals and humans in undeveloped societies use fibrous material to help clean teeth, such as fibrous wood, dried fruits or dried animal skins. | 26 | 24 |
ELI5: How does this whole net neutrality thing affect non-Americans like me? | A few things to consider:
1. if ISPs in America figure out how to make money off of content providers, then you can bet ISPs where you are will want to get some of that action. I'd worry about the cascade effect into your geography.
2. If your economy wants to penetrate the U.S. market with internet based anything, it will be more expensive to do so because those businesses in your locale will have to pony-up extra cash to ISPs so that customers get a really great, speedy experience. The playing field for entry into internet businesses will become significantly less flat than it is today.
3. Potentially, the diversity of "stuff" on the internet will suffer. Minority sites without the funds to pay fees for acceleration will become increasingly less quality because they'll be slower and marginalized. The diversity of stuff on the internet may go down. | 138 | 332 |
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ELI5: Are music tastes completely personal or does our environment play a role on them? | Do friends shape what we listen to? Are we born with certain music tastes? | Nature or nurture? It's both. Your environment can definitely play a role!
1. You like what you hear around you. This is how music is passed down in certain cultures. Like how Indian people like Indian music. Or if your mom is a classical pianist and played piano all the time, you probably have a higher chance of liking classical music.
2. You like music that speaks to you and that you can connect with emotionally. Maybe you like hip hop because your environment made you poor and now you're working really hard to "get yours" so the lyrics in hip hop songs are meaningful to you. | 10 | 24 |
ELI5 Why are there so many different internet browser and can I make my own? | So, there are two different aspects of an internet browser: the user interface and general usage, and the browser "engine" which does the transforming of a webpage to a more computer friendly structure. There are only 3 main engines now: gecko (firefox), blink (chrome, brave, opera, modern edge, etc., and which is based on webkit) and webkit (safari). You could make your own browser using an existing engine which would take some work, but the biggest codebase is the engine. Making your own engine would take in all likelihood a number of years. | 16 | 15 |
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How do denatured proteins in cooked food get absorbed and "used" in the body? | What I mean is: Proteins are essential components in the body for building all kind of things like building enzymes....I also know that proteins denature at high temperature and that this process is irreversible as you destroy the disulfide bond between the amino-acids. So if you cook your food for example an egg you are destroying the proteins conformation. How can it still be used in the body? Does the body regenerate the aminoacids for usage? | You already solved it - proteins are made from amino acids. Denaturing a protein just changes the conformation (shape) irreversibly. Your body would do that when you eat it. You need 22(?) essential amino acids in your diet that your body can't produce. Your body breaks down those amino acid chains and reconfigures them as needed.
EDIT - 22 total amino acids in human nutrition. 9 essential ones that cannot be synthesized from others. Thanks to /u/n00bz0rd | 450 | 1,128 |
ELI5: Do IQ tests actually mean much? How accurate of measurement of one's intelligence are they? | They are fairly accurate in the sense that whatever they measure, they measure it consistently and it is reasonably correlated with true intelligence. If you score well, you are smart, if you score poorly, you are either less smart, or you have a specific deficiency that makes it hard to take tests.
There is some evidence to suggest there is culture bias in how tests are written. However, that does not completely invalidate them, it merely means the results are sometimes skewed against people not part of the dominant culture.
| 46 | 65 |
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What types of Economist jobs are the most prevalent in the private sector? What do people do in these jobs? For instance what does a corporate economist do? | Non-native English speaker here.
&#x200B;
It seems that virtually all the occupations of an Economist is in the government. There does not seem to be that many Economist jobs in the private sector.
I am referring to Economist occupations here and I am not talking about people with a background in Economics who goes on to be a Financial Analyst within a business or do any other job other than that of Economics regardless of their occupational title.
&#x200B;
My question is:
\- What percentage of Economist jobs are in the private sector?
\- What are the *types* of these jobs?
\- What do people in these jobs do on a daily basis? For instance what does a corporate economist do?
&#x200B;
PS: I know these are basic questions, but I couldn't find any information on this topic even after weeks of searching. Maybe I am using the incorrect search terms in Google because English is not my native language. If anyone can guide me to a PDF or link online where I can get the information in my questions that would be great as well.
Thanks in advance. | In the banking industry there is a demand for PhD economists. Typically from the best schools and usually with a focus on Financial Econometrics.
Also real estate companies need economic analyst to study the housing market. But typically a BA/BS is enough. | 21 | 67 |
How should Schopenhauer’s Philosophy be reconciled with his essays? His essays teach one how to live the good life materially, his philosophy says life is simply suffering, and preaches music or asceticism as the way to overcome the will to life. | Schopenhauer prefaces his essays on living a good life by saying the essays cannot be reconciled with his main philosophy. The essays are a compromise where he ditches core ideas to give people something a little more practical. The first paragraph of one of his essays on attempting to live a happy life essentially says that living a happy life is impossible per his primary philosophy however if one were to attempt living a happy life, this is how one should go about it. | 33 | 33 |
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What exactly is a linear transformation? | This is a basic question I know but I cannot wrap my head around it. I understand the conditions under which a transformation is linear (although I could not tell you exactly what the significance of it is) given here. What I don't get it this. The transformation y = ax + b is non-linear but it is the equation of a line. It seems to me that if you took all of the x points and scaled them then shifted them that should be a linear transformation. Please help me.
I stumbled upon this question when looking into the relation between Celsius and Fahrenheit (F = (9/5)C+32). Both Fahrenheit and Celsius scales are linear correct? If they are, how can the transformation between them be non-linear? | Linear transformations preserve addition and scalar multiplication (as you've said you already know).
Let's see what happens when we try the transformation f(x) = ax + b.
*Addition*
We need f(x1 + x2) = f(x1) + f(x2)
f(x1 + x2) = a(x1 + x2) + b
f(x1) + f(x2) = ax1 + b + ax2 + b = a(x1 + x2) + 2b
*Scalar multiplication*
We need f(kx) = k f(x)
f(kx) = a(kx) + b = kax + b
k f(x) = k(ax + b) = kax + kb
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So f(x) = ax + b doesn't meet either of the criteria for a linear transformation. You are right, though, in saying that it describes a line. As you can see from the calculations above, the problem in both cases is the constant term (b). Without the constant, the transformation f(x) = ax would be a linear transformation.
f(x) = ax + b describes an *affine transformation*, which is not linear, but does still map lines to lines.
| 16 | 18 |
How do barometers measure altitude accurately when air pressure is constantly changing? | Fitness watches or bike computers - probably some phones too - track altitude change via air pressure change, accurately enough down to the foot/metre.
How can they do this when the air pressure is always changing.
And how can they be accurate down to feet/ metres? | If your question is how is this possible if there is a daily variation of the sea level pressure? Off from the 1013.25 average?
First, the pressure difference between different altitudes is (almost) absolute - so you can always easily measure the vertical speed. By tracking the difference you know by how many meters you moved up or down. The pressure at 0 altitude doesn't matter - only the difference does.
Those that give you an absolute height reading - it is always based off some estimate for the current ambient pressure. Those found in smartphones and GPS-enabled variometers use the GPS the get a rough altitude estimate. GPS has about 10m vertical precision. Then they use it to calibrate the barometric altimeter, which is much more precise. Some are better at doing this, others frequently give erroneous readings unless you manually calibrate them. | 16 | 23 |
Why do entry level jobs demand 3-4 years of experience ? | About to graduate next year with a CS Degree and almost all entry level jobs on every possible platform i could find (like linkedin , angellist , indeed etc) demand 3-4 years of experience while paying the shittiest of salaries they possibly could . Any advice on where to look for a mern stack developer job that doesn't demands experience from a fresher rather focuses on projects and skills to hire people ? | As a general rule of thumb, subtract 2 years from requested experience. 3-4 years might actually be looking for some one with *some* professional experience, but if they say they want 1-2 years of experience, they'll probably take a fresh grad.
The situation arrises in a number of ways, but mostly it boils down to an absence of communication between engineering (who wants to hire someone) and hr (who write job postings). Engineering wants someone familiar with a tool, hr translates that into a couple years of experience with a tool that anyone could pick up in a month. It's not HR's fault per se, learning new "resume-relevant skills" is just a lot more common in software than it is most other fields. | 43 | 59 |
ELI5: How do we know instruments used in measuring the properties of distant objects (e.g. the mass of a star) are calibrated correctly? | Calibrating any measurement instrument is a combination of trial-and-error and testing agreement with mathematical models. If an instrument is measuring the thing it is designed to measure, doing this consistently, and getting results that make sense according to calculations about what they could/should measure based on how they work, then we would generally take them to be reasonable instruments. As our understanding grows, and as we encounter, analyze, and correct errors based on unexpected influences (e.g. human error, poor construction, degradation of the instrument, etc.), the idea of an acceptable instrument may change a bit, but the general idea is there. | 11 | 35 |
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[Star Trek] How the heck do you burn food when using a replicator? | One of my buddies who was stuck on Voyager during its extended trip in the Delta Quadrant always tells stories about during potlucks the great and powerful Captain Janeway always managed to burn food that she made with replicator. How in the world did she manage that? That said apparently the burnt food was still better than anything the chef Neelix made. | You can specify what temperature you want your food to be. Janeway could be setting it too high, so the food burns after it's been made.
It's also possible that replicators can toast food after it's been replicated. Some present-day microwaves can do that. Maybe the interface is fiddly, or Janeway is an indifferent cook. | 12 | 20 |
The 2nd Law of Thermodynamics dictates that a black body is a perfect absorber AND emitter of light. How does a black body emit light? | This also means the sun is a perfect absorber of light. How does the sun absorb light? | It is important to understand that light does not necessarily mean wavelengths you can see. Radiowaves and ultraviolet are light as well. A blackbody will absorb light at a high wavelength, which will excite an electron. When the electron drops down to an unexcited state, it will release a photon, however, it won't necessarily be of the same wavelength as was absorbed and usually is of a lower energy wavelength with the extra lost energy going to heat.
The sun actually does absorb light. The photons that are created from fusion go in random directions from inside the star. A photon will go until it hits something which often isn't far considering the density of a star. As before, when a photon hits an atom the photon is absorbed, the electron jumps up an energy level. The electron drops and releases a photon and the process repeats. Sometimes the photon goes closer to the surface, sometimes it goes deeper. It can take a photon thousands of years to get to the surface, then it takes 8 minutes to reach earth. | 21 | 18 |
ELI5: How is it decided how much memory a picture takes. Like what makes a difference and why do some pictures take more memory than others. | This depends on the type of compression used and with many compression algorithms depends on the complexity of the photo.
If the photo is comprised of simple shapes and solid colors then it compresses better than a complex scene with many colors. | 18 | 50 |
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I believe if there is a minimum wage, unpaid internships should be illegal. CMV | Pretty self explanatory from the title. Unpaid internships are jobs that pay less than minimum wage. Therefore they should be illegal. | Any legal unpaid internship can't be called a job because it cannot benefit the company in any way. So if the company isn't benefitting from your work, why should you be paid?
Edit: Here are the criteria for an unpaid internship in the US. If your experience could impede on the company, why should you be paid?
1. The training, even though it includes actual operations of the facilities of the employers, is similar to that which would be given in a vocational school.
2. The training is for the benefit of the student.
3. The student does not displace a regular employee, but works under the close observation of a regular employee or supervisor.
4. The employer provides the training and derives no immediate advantage from the activities of the student; and on occasion, the operations may actually be impeded by the training.
5. The student is not necessarily entitled to a job at the conclusion of the training period.
6. The employer and the student understand that the student is not entitled to wages for the time spent training. | 12 | 41 |
ELI5: Why are clothing brands like: Ralph Lauren, Kenzo, michael Kors So expensive? | i just looked at some online stores and found out that most of their clothes costs above 200 euro's/dollars for just sweaters!, even the polo's from ralph lauren are like 60 bucks or more, why is it like this? | It's a combination of perceived quality, a certain amount of actual better quality, and status.
People are willing to pay a premium price for shirts with logos to show that they have lots of money to spend on wearing "status" logos. | 46 | 30 |
[Harry Potter 7] When they started processing half-bloods,considering them as no witches/wizards, what was their sentence? What did they do to them? | There was a whole range of possibilities. The simplest and most "merciful" route would likely be the snapping of their wand followed by a Memory Charm before releasing them into the care of the Muggles (such as it was). Remember, the Muggles' *dominion* was Voldemort's overall goal, not necessarily their *genocide*. | 22 | 21 |
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ELI5: What do spies do in real life? | Both in a modern and historical sense | Gather intelligence in different forms, communicate that information back to others, and sometimes try to stop the "enemy" from getting certain info, and sometimes spread false info. If you ever get the chance to visit DC, there is a spy museum you might enjoy. | 75 | 81 |
ELI5:Why are lenses round but the camera sensor and resulting image square? | For SLRs the attachable lenses are circular, yet when you look through the camera, as well as the image taken, the shape is rectangular. | When making lenses for a camera, it's difficult, if not impossible, to achieve a uniform distortion of light throughout a rectangular lens. A circle is very uniform and makes all refraction of light through the lens the same. Rectangular image sensors are also easier and more cost-efficient to make than circular ones, assuming you'd even want a circular sensor.
Basically, it's the cheapest and easiest way to manufacture. | 21 | 33 |
ELI5: Why do small, superficial wounds heal faster on certain areas of the body, like the mouth, than in other areas? | The mouth is special for two reasons, one it contains certain chemicals that aid wound regeneration and saliva, saliva provides moisture, cleaning/defence and more good chemicals.
In the rest of the body, it differs, certain places in the body have worse blood flow, which inhibits wound regeneration. The dimensions of the wound are important too, if it’s a cut ; it’s easier to heal, as less time/material is required to make a ‘block’. If it only perforates the skin layer (epithelium) and not go further it is also preferable as epithelium grows quickest, if it perforated deeper, into the connective tissue, where you have Nerves and blood vessels, regeneration is gonna take longer. | 17 | 57 |
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ELI5: why is private education in England called "public school"? | It's confusing. | A small number of older private schools are known as "public schools". When they were founded, the name made more sense because it indicated that they were open to the general public rather than being tied to membership of a particular church or other organisation.
Other private schools tend to refer to themselves as "independent schools", emphasising their independence from the government, but "private school" is also used. Government-funded schools are known as "state schools". | 18 | 17 |
[MCU] Ok, so Ant-Man can lessen the distance between the molecules in his body while retaining mass, making him strong. So when the distance expands and grows huge, why didnt he just flop and fold on the floor? | Pym Particles can increase/decrease size AND mass. The point of the suit is that it carefully regulates these changes without the user having to do advanced calculus every time they grow/shrink, to maximize the effect of the change. That's why when he's small, he hits like a truck yet can still walk across plant leaves when it suits him: his mass is literally shifting on the fly. | 403 | 337 |
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ELI5:How did time become standardized across the world? | How did we get all of the countries to accept the hour/minute/second system? | Multiple cultures simultaneously developed a system of 'hours' equal to or divisible by 12.
- The ancient Egyptians divided the day into 12 equal parts, 10 during the day and 2 at twilight.
- An ancient Greek astronomer, Andronicus of Cyrrhus, built a structure called the Tower of Winds which encompassed sundails, water clocks, and other timekeeping mechanisms to divide the day into 24 equal parts.
- In ancient China, the day was divided into 12 equal parts.
- In ancient India, the day was divided into 24 equal parts, 12 for 'day' and 12 for 'night'
Why 12 in so many different places? That's the number of lunar cycles in a year, which is where the concept of 12 months comes from. This made it easy to standardize 24 hours for a day around the world, as virtually everyone was already using 24 hours, or could easily adapt to it by dividing their 12-hour days by 2. Using a standard time system made trade and commerce much easier. This 'basis of 12' system is known as the 'duodecimal system', and comes from prehistoric lunar calenders.
That explains hours, but how did we get 60 minutes in an hour?
The ancient Greek astronomers relied on methods by their predecessors in Mesopotamia, who based all of their calculations on a sexagesimal system, or based off of the number 60, which can be traced back to Sumeria in about 2000 BC. That heritage is also why we have 360 degrees in a circle - as a result of the base 60 system.
Minutes and seconds came along a lot later than hours did. Before this, hours would be divided up into halves, thirds, quarters, what have you depending on need and region. There was no need for this level of precision for much of history.
Minutes and seconds were introduced sometime around the advent of mechanical clocks in the 14th century. There was a need for more accurate sub-units of hours. The world was still using the base 60 system at the time, and so hours were divided into 60 equal parts called minutes, which themselves were divided into 60 seconds. The base 60 system is also why clock faces are round.
Humanity transitioned from the base 60 system to a decimal system, or base 10, around the 17th century. It is easier to divide things by 10 than it is by 60. The sub-unit of seconds was not needed before this transition. That's why a second is divided into 1,000 milliseconds, which can be divided by 10, not 60 or 12.
Hope that was ELI5 enough! | 59 | 88 |
ELI5: Why does seafood go bad faster than land food? | It seems that fish and other seafood goes bad more quickly than land animal meats, and when it does, it goes bad seriously, being more likely to result in food poisoning. Why is this? | ELI5 Version: The parts of a sea animal we're eating often live at temperatures just above freezing, so does the "stuff" that helps the body of the animal operate. If you put a beef steak in the fridge, the "stuff" (enzymes) just shut down, where as if you put fish in the fridge, the enzymes are continuing to function at the lower temp. Bacteria can feed off the breaking down of the enzymes/bio product since they're still active. | 2,196 | 1,014 |
REALLY basic question about how money works in a closed economy | I'm having trouble understanding where new currency comes from when value is created in an economy, and how it enters circulation.
I'm thinking of a hypothetical closed economy with say 10 people. Each person produces 10x of goods/services of value $10. They all exchange. Let's say one decides to innovate, and produces 10x goods of value $20. How can they sell their goods without others going into debt? The only way I see is if the others increase their money supply, but this feels wrong - how can they increase their money supply without having produced something commensurate with that increase?
What seems to follow is that if one person adds value, everyone else has to add value by a similar amount to prevent from going into debt. This doesn't sound right. And even if it's correct, how does the new money enter the circulation?
I understand this is an incredibly rudimentary question, but maybe so rudimentary it isn't articulated, so I've kinda missed it. | If you have a fixed amount of currency in circulation, the currency would become worth more as prices would decrease over time. If it was impossible to create or destroy currency, then as new goods are produced prices would decrease.
However, basically all monetary systems run on a fractional reserve system which creates money to through debt. This process is controlled by a central bank.
| 11 | 15 |
[Star Wars] Surely they must have a way to just regrow lost limbs by this point, right? | We've seen so many robotic arms and by this point, these wars have spanned 3 generations of a family. Are you telling me medical technology hasn't progressed in like 60+ years across any planet when there's already science like near lightspeed transportation, etc? | They have bacta, which promotes stem growth and has been shown to regenerate damaged organs. But the amount and time needed to regrow an entire limb (and the complications and readjustment period afterwards) would not only be prohibitively expensive but also require Luke (or Anakin) to cease being involved in military operations in a desperate time. | 31 | 15 |
[40k] Warp entities are maxe through belief. Countless billions of people believe in the god Emperor so it must exist in the Warp. But the Emperor is a powerful psycher. Is there a vastly powerful warp entity that thinks it is the Emperor, but in fact is not and has nothing to do with him? | The relationship between *beliefs* from entities in the materium affecting and/or creating entities in the immaterium, in turn impacting events and entities again in the materium, is a tenuous one, and often overstated in recent times.
For instance: while /u/TLhikan is correct in stating that emotions feed chaos gods, it should be noted the extreme duration of time that it took to actually foment a change in the warp under even "ideal" circumstances.
To whit: the Eldar rose to prominence well before mankind had two telomeres to rub together. As a psychic race, each eldar shines like a beacon through the warp far brighter than the most powerful human psyker.
As an entire race, the Eldar engaged in excess, debauchery, and pursuit if pleasure for thousands of years, only birthing Slaanesh "recently" (around M30).
The less psychically powerful humans have only been worshiping the Emperor for around 10k years, and if you forgive me for saying so, their worship of the Emperor is not as strong or clearly defined as the Eldar's dedication to hedonism.
On some planets he's a philospher king, others a warrior prophet. That's why it's the cult of the emperor — there are millions of different expressions of this worship, and untold legions of ecclesiarchs dedicated to discovering, evaluating, and cataloging them. There is, ironically, no unifying force or emotional tide to bring this all together in a way that would birth a chaos god. | 30 | 50 |
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ELI5: When picking up a prescription at a pharmacy and you have to wait 20-30 minutes for it to ready, what are they doing during that time? | Checking with your doctor that the prescription is valid. Checking the dosage instructions for sanity. Checking other medications you are taking for interactions that could hurt or kill you. Checking that your insurance will cover the medication. Counting the pills. Recounting the pills. Having a second tech triple-count the pills. Complying with state, federal, and company documentation rules. Passing it to the licensed pharmacist to sign off on everything. Then the packaging and such.
They aren't just slinging pills by your request back there. | 110 | 71 |
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ELI5: What is a p value and a null hypothesis in scientific research and how significant are they | I’m starting to get into science a lot more these days but I do not know what p values and null hypothesis are.
Appreciate the help. Thank you. | Going to start off with some relevant definitions first
Dependent variable — the thing that’s being measured, a response variable (ie. heart rate)
Independent variable — the thing that’s being manipulated or set by the researchers; the variable that is hypothesized to cause a change in the *dependent* variable (ie. a drug treatment)
Population — the group being tested. Important to note that the conclusion can only be generalized to the population of the study. If the experiment (“sample population”) only includes men of Asian descent aged 45 and over, then the conclusion cannot be assumed to extend to men of other backgrounds, women, young men, children, etc.
The alternative hypothesis is the research question in the form of a true/false statement (This drug affects heart rate).
The null hypothesis is the “blank.” It assumes there is no relation between the independent and dependent variables (This drug has no effect on heart rate). With no evidence, we default that the null hypothesis is true. The experiment aims to disprove the null hypothesis in favor of the alternative.*
The p-value is the probability of getting the observed result under the assumption that the null hypothesis is true — that there is no relation between the variables.
A small p-value means that it would be very unlikely to observe this result by random chance; therefore, it is likely that something is causing it. In a well-designed experiment, the cause can be attributed to the independent variable.
*Just because a result is not significant, does not necessarily mean that the null hypothesis is definitively true, it just means we did not find evidence to say otherwise. Same goes for the alternative. Just because a result is significant, does not mean it is the end-all explanation. We just have evidence to support the conclusion. That’s not a go-ahead for all you conspiracy theorists out there to say “Gotcha!” If the results can be observed time and time again, then that’s more and more evidence to support the explanation. | 51 | 48 |
ELI5: Why is AC better than DC ? | The main benefit is that you can easily change voltages/amps with AC using a transformer.
Voltage and Current have inverse relationship, but power used/lost depends mostly on current, so being able to transport it as a very high voltage, and very low current means you can use much smaller wires, which cost a LOT less when your talking about miles and miles. Then substations you transform it to medium voltage, then low voltage at all your houses, and businesses etc.
With DC switching between voltages takes much more complex equipment thats more likely to fail, AC only takes some wires rapped around a bar of iron, so its relatively cheap, and unlikely to fail.
Source EE working in power distribution. | 2,546 | 3,898 |
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I think unmarried fathers should have the right to absolve themselves of responsibility to their offspring. Please CMV. | In many countries, non-custodial parents can be sued for child support - and in the majority cases, the plaintiff is a mother seeking payment from the child's biological father.
An unmarried mother has the option to absolve herself of responsibility to the child by postcoital contraception, abortion, or adoption; in many cases without the consent of the father. In contrast, the father has no such opportunity.
I think it's only fair he be given the option to absolve himself of responsibility to his offspring (perhaps by signing away his rights as a biological parent).
***
As a pre-emptive retort to the idea that you 'reap what you sow', and that the father has a responsibility to use contraceptives:
* Contraceptives are not 100% effective. Whether through malfunction or incorrect usage, mistakes do happen.
* The mother has those same responsibilities, but has the *extra* option of absolving responsibility after conception.
Unwanted pregnancies do occur, and in those situations the father should also have the opportunity to absolve himself of responsibility.
***
Please change my view. | The reason why noncustodial parents have to financially support their children is not to punish them or to equalize the contributions of each parent, but to ensure that the child is adequately provided for.
In many instances, the financial resources of a single parent will not be adequate to raise a child. In those cases, there are only a few options: 1) let the child starve/go without clothing/schooling/etc. 2) have the state provide assistance 3) have the absent parent provide assistance. We have decided that it is better to require the absent parent to provide assistance than to let the child go without or to require the taxpayer to assist. In both of those cases, a completely innocent party has to suffer.
In essence, you should ask not whether it is fair that the father has to provide support while the mother can choose to abort/adopt, but whether it is fair to make you and me support the child instead of the father. | 79 | 50 |
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