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What would happen to a poor country, if it sets the retirement age to 55? | Will this country succeed in brining down unemployement and stimulating the economy by injecting millions of new workers (customers) into the economy? or will the pressure imposed on the retirement system be much hard to handle? | Could you clarify what you mean by "set the retirement age to 55"? You mean that the government mandates that no one older than 55 works? Or that it lowers the pay-out age of it's social security program (many poor countries don't have these) at 55?? Or something else? | 31 | 35 |
CMV: Gender as a social construct should be excluded from identification, and the law should not prohibit misgendering. | I know something like this has been posted before, but the user is often arguing against gender being defined as distinct from sex. I am not here to make that argument. While I think the distinction is largely overcomplicating things, words are defined by collective agreement of meaning, which makes the redefinition valid. I want to make that clear. That being said, I am *fundamentally* opposed to legislation that would legally require a person to acknowledge the distinction. There should be no law prohibiting misgendering. The only repercussions should be social.
Also, gender should not have any place in identification for obvious reasons. Gender is not an identifier, since if we agree it is subjective. This is especially true if we acknowledge gender-fluidity. There is no way to confirm someone's gender, therefore it has no place on identification. There are definitely ways to confirm someone's biological sex, however.
EDIT: I have decided that private entities should have legal requirements to not discriminate, in which case the law would prohibit misgendering. Well, more specifically it should be included in anti-discrimination laws. But fair enough.
I have changed my mind.
Edit 2: A lot of this has led me to question whether sex on ID is helpful anyway. I think ID is usually to confirm your identity at a glance, and the photo is clearly enough for that. The rest is secondary and largely unnecessary.
Which means I'm likely not responding to new comments. My mind has officially been changed. I'm really thankful for all you guys participating
Cheers! | The ways you check for bio-sex is to look at genitals or test Chromosomes. That is not acceptable for identification in public, or quick reference for ID. The Gender that someone displays is the factor that is useful for the vast majority of ID usages as it is some clerk making sure you are the person on the ID when you are buying something controlled (weapons, medication, alcohol, tobacco, etc) or when the police are checking you out (looking for you as a suspect, or running your ID for a violation such as speeding). | 159 | 441 |
ELI5: On what do our eyes focus in pitch dark? | Like if it is pitch dark, do the eyes focus on the dark "wall" directly in front of them? Or are they just indefinitely trying to focus on something? Or are they idling because it is dark? :) Thanks! | Optometry student here. Your eyes have several stages of accommodation including tonic and proximal accommodation.
When your eyes have nothing to focus on they will relax to tonic accommodation which is the point where muscles rest with minimal nervous innervation.
If you suddenly hit a wall, your eyes will accommodate to the proximal distance of that wall based on previous life experience.
Edit: Accommodation is where the lens in your eye (imagine a magnifying glass) changes power to help bring a near image into focus.
Edit2: A few of you are curious about relaxing your eyes and accommodation to relieve eye strain. You can use the 20/20/20 rule: every 20 minutes stare at something 20 feet away for 20 seconds.
Edit3: Accommodation is fully relaxed at 20 feet (6 meters) which is why you're tested at this distance when at the optometrist's office. | 4,340 | 6,556 |
ELI5: Would it be feasible to make enough solar panels to generate enough electricity for the whole world? | [This](http://boingboing.net/2014/06/12/the-total-area-of-solar-panels.html) popped up on my dash recently and I wanted to know if this is or will be possible. This size of the square is pretty damn large though. | The key thing to know about the energy market is that the total supply of electricity at any one time has to match the total demand for electricity.
One of the problems with solar power is that it generates electricity only when it's sunny, and even then only during the day, whereas people tend to use most of their electricity during the evening or at night. That means you need a way to store all the energy that's generated during the day and used later that evening, and storage of electricity is currently quite inefficient and expensive. | 12 | 26 |
[Various animes] In animes where it is a worldwide known thing that there are individuals out there that can take down armies all the way up to crack planets, why are people not more skeptical when a 11 year old jumps in front of an army/group of baddies they not more cautious? | There are multiple reasons:
1) *First Contact Scenario*: In some worlds this is the first time it happens. Using DBZ as an example.
Nappa was the first time this was demonstrated and shown large scale. Flying ki users who were any destroyers were rare, see teen Goku against the Red Ribbon Army. But, he had problems with mechs and mostly took on infantry. Nappa was the first to show Earth a ki user could take on and destroy naval fleets.
2) *Rarity*: Such beings are unlikely. In DragonBall Z there are only six humans that could destroy the Earth if you count the two mutants.
Then you have four, or three depending on Kami's status, aliens who are leagues above humans. Then they begin breeding and this doubles the world nukers.
Expecting this one individual to be a powerful as you say is almost nil. Hercule is strong. He makes most humans look weak. He is a one in how many million? These one man armies are to Hercule what Hercule is to us. So rare and reclusive that over time the world thought the last time they showed up on camera was a hoax.
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How do modern nuclear reactors avoid service interruptions due to slagging/poisoning? | Was reminded of a discussion I had with my grandfather (~WW2 era nuclear science engineer) about how problematic reactor poisoning was in the past and especially slagging.
I believe more than a few of the US fleet of commercial reactors are at or are already surpassing 60 year total runtime licenses, was it just better designs or something else?
| There are two cases a reactor or core designer has to deal with, steady state operation and transient operation.
In general, poisoning is dealt with by having a large amount of hot excess reactivity so that you have xenon overrode capability. This means having sufficient hot excess reactivity to overcome any poisoning effects. Large light water power reactors are designed to run for up to 2 years continuously so they are loaded with a large amount of excess fuel to support that.
In steady state, the whole poison process balances out with excess reactivity and isn’t an issue. For transient conditions, like sudden drops in power or a scram, unit’s have xenon override capability based on their design.
For bwr plants, at full power you have a large amount of voids in the core producing negative reactivity. After a scram these steam voids collapse as the reactor shuts down, returning that reactivity and making it available for restart. Xenon may complicate ramping the unit back to 100% after the restart due to thermal limits, however bwrs always have xenon override capability and can start up in peak xenon at virtually any point in the cycle.
PWRs have xenon override until they are in the end of their cycle in coastdown with most of all of their boron diluted. For a pwr, you reclaim a small amount of reactivity as the reactor cools down to hot standby after a trip, but you rely on the hot excess reactivity to overcome peak xenon.
For CANDU plants, these units have very little hot excess reactivity, and can easily be poisoned out. The plant is designed to only do a full reactor trip when absolutely necessary, and in other cases runback to 60% or 2% based on he situation. At 60%, you have enough neutron production to prevent poisoning from shutting the core down. At 2% you have a time window where if the problem condition clears you can ramp back up to 60% before xenon catches up to prevent a xenon peak from poisoning the core out.
Hope this helps. | 891 | 3,405 |
ELI5:How does an LED bulb work? How is it different from fluorescent? | A fluorescent bulb works by using electricity to excite gas within the bulb, which releases photons (light particles) which then excite the bulb's coating which causes it to release photons in the visible spectrum.
An LED is a light-emitting diode. It's a little complicated to explain, but essentially there are two electrodes, one with an abundance of electrons, and the other with a lack of electrons. When you apply a potential across that it it allows electrons to flow from the material with abundance to the material with a lack of, which in turn causes photons to be emitted. | 28 | 122 |
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[General] what are some good military tactics for large-scale, ground based, superhuman combat? with flight, enhanced speed, enhanced strength, and other abilities, what better strategies are there than an all-out brawl? | questions a bit to vague, exact powers would be needed to formulate any sort of plan, if there just flying bricks the battle strategy wouldent change much beyond higher scale collatoral damage and being able to extend it upward
worm is a an excellent read if you want examples of powers being used very creatively and with actual strategy | 50 | 63 |
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eli5 Why do devices still briefly have power when unplugged? | Say you unplug your tv, the standby light will remain on a few seconds before going off? | Electronics use components called capacitors to regulate voltage. These capacitors act like little, short-life batteries - which still hold a charge when the power source is disconnected. The stored power then drains out and keeps other components powered for a short period of time. | 168 | 80 |
ELI5: Why do sparsely populated areas tend to vote Republican/Conservative? | You can see this on a state level:
http://www.google.com/elections/ed/us/results
If you zoom into any red or blue state, the sparsely populated counties usually end up red. Is there a simple reason why? | It's all about population density.
In an urban area, having a lot of people around is the norm. This has benefits and disadvantages. It means help in any number of ways is usually nearby (police, fire, you need a jump from your neighbor, etc).
It also means that other people's behavior can adversely affect you because you live in close proximity to them. If your neighbor constantly plays loud music, this can greatly impact your quality of life, so you need to rely on local government and society to regulate that person's behavior (noise ordinances).
In both cases, whether trying to get help or prevent other people from negatively impacting you, government has the power to make your life a lot better because you and all your fellow city dwellers are concentrated in one place.
Compare this to the rural lifestyle. Your nearest neighbor might be 10 minutes away by car. In this case, you would regard a noise ordinance as anything but helpful. Your neighbor couldn't buy speakers loud enough to bother you, so of course you'd take umbrage to some cop hanging around your property line telling you to turn your music down all the time when it hurts no one.
Similarly, government benefits are of reduced value to you. The average area that must be covered by the local fire department might be hundreds of times bigger than your average city precinct. Even if you do call for help, logistically, you realize it could be a long time until they get there. So naturally it doesn't make a whole lot of sense to rely a lot on government services that require you to be relatively close.
All of this adds up to: rural areas tend to be more self-reliant and mistrusting of government, while urban populations tend to be willing to rely much more heavily on government services and regulation. But: **only when locality matters.**
What does that mean? Well, note that rural areas are perfectly happy to rely on government services when those services can be rendered at a distance. For instance, farm aid. Washington DC can cut a check from thousands of miles away to help a farmer grow crops. In these cases, rural areas tend to like government regulation when it benefits them.
So what "big govt / small govt" is really about is which population is better able to extract utility from government. This is why Republicans tend to favor government involvement in things like farm aid even though that's inconsistent with their "small govt" core message. | 83 | 43 |
ELI5: What is the slow motion effect we experience during car accidents or other traumatic events? | I've read that it's not really about increased perception, it's about increased memory formation. While adrenaline does create a heightenbed state of awareness and alertness, time really only seems to slow down in your *remembering* of the event, since your body created detailed memories of every instant of it (a snapshot every quarter second, as opposed to one every second, for example) to help you learn from it and increase future survival chances. thus the density of memories you have of the event makes it seem in retrospect like time was moving slowly. | 60 | 70 |
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CMV:I think you don't need to go to college in order to have a good career and or job | I was born in Khartoum,Sudan.My family and I moved to the US about 5 years ago, I'm currently 15 years old.My dad has a degree in engineering and my mom in accounting.I personally think that people have been brainwashed to believe that you need to go to college in order to be successful in life, which I think isn't true at all.I don't think that college isn't good but I believe it isn't worth all the debt that most students have to pay off after graduating and also most of the people I know that have gone to college don't even have a job in their field of study or at least not as soon as they graduate.CMV about college. | Highly depends on what you want to do. If it's anything STEM then you're going to need a degree and advanced education in order to be successful. However if you're satisfied doing low-tech or low-skill jobs or go into the trades then no, you don't need a traditional degree. Plenty of people go into business for themselves and ascend through the ranks with very little education and become successful. | 10 | 17 |
ELI5 Why is it that poison ivy can be spread by scratching but you don't get it on your finger tips? | Tolerance, thickness, etc.
Your hands are really sensetive, it helps us use them better, but they're also very tough, because we use them so much.
So you can get poison ivy on your fingertips, but the poison isn't strong enough to damage you through the strong skin on your fingers, but then you spread it to other, more sensetive and weaker areas of your skin | 13 | 25 |
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ELI5 How does Google photos separate photos into such specific categories without them being labeled manually. | With machine learning. A computer program has looked at many many images that _were_ labeled, and it learned from them what sorts of labels to put on other photos. It learned by looking at an image that people had labeled but not looking at the label, guessing a label and then comparing the result with the label given by a human. Then it made a note of whether it was right or wrong. Doing this many times with many different images it learned to label automatically. | 25 | 24 |
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ELI5: How do they determine statistics like “8 million people in the US have __ disease and another 1 million are undiagnosed”? | I work in healthcare and there have been multiple times where I’ve seen disease prevalance statistics that include “undiagnosed cases”. If they have not been diagnosed then where do they get those numbers from? | By reliably measuring rate of infection in smaller populations then extrapolating the results to larger populations, researchers compare the extrapolation against reported cases. The difference between these quantities becomes the assessment of undiagnosed cases, which is always subject to some measure of error. | 47 | 32 |
CMV: There are only two genders | Yeah, I know that it's a meme at this point with the whole Change My Mind thing. But, I still never understood how there are more than two genders. With the exception of a few rare genetic disorders, people are born with either XX or XY chromosomes, which determines their gender. I know that there are people who truly feel that they are some third/non binary gender, but that doesn't change the science. Why is different than someone who truly believes they are a duck? I think the science is more important than what people feel. But, I'd like to hear reasons why gender is fluid and can be non-binary. Change my view
Edit: I don't think I will change my mind, and I'll probably stop responding to this thread now. I am going to address some common arguments here.
"You are confused between sex and gender. Sex is based off of chromosomes, gender is simply how someone identifies themself within the rules society places."
Gender and sex are synonyms. Modern gender theory says otherwise, but that's exactly what I am arguing against. How someone feels is not the determining factor in their sex, it is their chromosomes.
"People can identify with 'non binary' or something else because they do not believe they fit neatly into either man or woman."
People can say they are whatever they want. This doesn't mean other people should or should be required to adhere to this. Other people determine your identity. Hitler thought he was a reasonable person. We do not call Hitler a reasonable person, because we determine his identity, not him.
"You can't exclude intersex because they are different and/or rare."
I am not excluding them because they are different or rare. I think that we can all agree that people with XXX or XXY are exceptions to the general population, and do not fall neatly under male or female.
"You are going against science and academics by not accepting modeen gender theory."
There are qualified people who believe that there are only two genders, like Dr. Jordon Peterson. I understand that most of you are not fans of his, but he is an example. Besides, even though I acknowledge I am not the most qualified person to talk about this, a layman can still have an opinion that goes against a consensus. Like how people used to use Darwanism to "prove" that blacks were inferior to whites. They called that science.
Also, I know that I have offended people who are trans or identify as nonbinary. I do not express my view to be offensive, and I'm sorry to those who may be offended. But, science should not be based on what people feel. It should based on fact, even if facts may be offensive.
Still, thanks to everyone who tried to change my view.
| Try this:
Gender isn't sex. Gender is a *set of stories we tell ourselves* about our identities as persons. This set of stories does *include* stories about our bodies -- but it's not *limited to* stories about those bodies.
I'll prove that claim --
What gender is Optimus Prime?
Optimus Prime does not have sex. He has no chromosomes and no sexual anatomy. But he does have *gender*. We identify him with a set of cultural narratives that have to do with physical power, strong leadership, fatherly guidance, a deep booming voice, etc. We exempt him from the "penis" stories because those are not important to who he *is*.
There are more than two genders because there are more than two *sets of stories* about our identities as people. Other cultures already have such sets, like the Native American Two-Spirit people, and the Bugis people of Indonesia with five genders. And now in Western culture we have people constructing new sets of stories for new genders. How successful these new constructs will be in the long run remains to be seen -- they could fade and be forgotten if they don't take hold in our culture. But they do *exist*. | 97 | 72 |
If I have two blankets of different materials, does the total insulation change depending on how I layer them? | for instance, I have a cotton sheet and a polyester blanket.
Would having one on top trap heat more effectively than the other way around? | Thermal mass can have an impact if there are changes in temperature involved. Having the denser layer on the inside keeps the temperature more constant.
NZ's building code, for example, requires that new buildings built with concrete blocks have them within the insulation layer, not outside.
Other effects that could have an impact are wind and water. Many types of insulation get significantly less effective if full of water, and also perform better without airflow, e.g. glass-wool batts. | 34 | 76 |
CMV: Affirmative action/positive discrimination should never be used | Honestly, I see affirmative action (as you muricans call it) is both an unjust and ineffective way to solve problems in society.
Firstly, the morality of it. I think justice should always happen on an individual basis. While this isn't strictly a 'punishment', it certainly feels like one. I live in the UK, I'm not white English, but I would never dream of demanding an unfair advantage over those who are. It is obviously not the fault of either of the affected individuals that such a problem exists, so why should we make them be affected, sometimes negatively, by it? Why should people be made to suffer for something they didn't have any part in doing? Shouldn't people be selected on ability and competence? If most of the people who are best at a particular job are white, so what? Who cares? They're the best people there are, they should do it.
It also tries to simplify really massive trends. Imagine some researchers calculate white people earn 10% more than black people, on average. So, the government decides white people should pay 10% more tax. Nice, isn't it? Well, sure, maybe on average, but that white family struggling to feed its children are not gonna be happy, but the black billionaire might. I know these are cherry picked examples, but still, some people are going to screwed over by it.
Finally, I don't think it's the best thing to do. Sticking to my above example, why should we help people based on race, and say "we'll help everyone who's black, because they could be poor" instead of just "we'll help everyone who's poor, in which black people make up a proportionally larger amount"? Why are we supposed to be helping people because the colour of their skin *might* disadvantage them, instead of people who are *actually* disadvantaged? It makes 0 sense to me.
So, there's my long ramble. Please, don't call me a racist :)
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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!* | > Shouldn't people be selected on ability and competence?
Yes, and the underlying premise is that they aren't necessarily, all things being equal. Most people can agree that, in a world entirely free of prejudice, the best candidate will win by merit alone. The argument here is precisely that the "best candidate" isn't determined by merit alone; that the decision is tainted by various biases reducing the chances of minorities. Also, if some classes are advantaged over others for some time, there's a good argument to be made about this comparative advantaged not simply fixing itself. Getting access to the best schools and then the best jobs for generations will create a structure where some classes will *always* appear to be the best candidates. On the one hand because they might be, but also because they had much better chances to be. While they very well might be, there's nothing wrong with trying to even out the equation by inserting variety into the pool. This way, you can try to diminish the comparative advantage and lead to greater diversity, which addresses both problems on the long run.
| 20 | 56 |
[Alien] If xenomorphs inherit traits from their hosts, what, if anything, do they get from humans that other hosts don’t give them? | Nothing in particular. The traits they inherit are just for adaptation to the prey's environment and appropriate size for hunting them. If it's grabbing a human host it wouldn't make a sense for the resulting Xenomorph to be the size of a rat or an elephant when it wouldn't be able to hunt more humans effectively. The other adaptations are more minimal but regarding how it's senses are tuned for different atmospheres and light levels. Overall the xenomorphs Rea only concern themselves with how big or small they need to be or if their prey is adjusted for living in extreme conditions. Eventually these traits are shed as more pure xenomorphs are molted out of the younger ones that don't hunt as much. | 31 | 19 |
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Why wouldn't crossing an event horizon mean instant death? | As I understand it, once inside a black hole all paths lead towards the singularity, no matter the properties of the matter that falls in, so I assume bodily functions like blood flow would fail immediately because it would require some small motion away from the singularity.
I have also read that in a supermassive black hole one could survive crossing the horizon (radiation aside) until very close to the singularity. Is this true, and why?
| Blood can flow to different parts of your body while still getting closer to the singularity. Consider when a person is flying on a plane traveling at hundreds of kilometres and hour. All the parts of his or her body are always traveling in the direction of the plane with respect to the ground (and so are always getting closer to the destination). Nevertheless blood can flow towards the back of the plane by flowing slower with respect to the ground than other parts of the body. | 19 | 45 |
[Update] Prof claims first authorship for a paper I wrote 75% of. | Hi everyone,
[Previous Post] (https://www.reddit.com/r/AskAcademia/comments/4kywje/prof_claims_first_authorship_for_paper_that_i/)
Thanks for the great responses to my previous post. They really helped, and made me feel less alone and bitter. Lol.
Anyway, loads happened in these couple of weeks. I thought I'd give a brief update for anyone who is interested.
1. I found out that Prof didn't even write the 25% I thought he did. He copied and pasted big chunks of paragraphs from the collaborator's papers (we're framing the study based on collaborator's theoretical framework). How did I find out? Well, the first time I realized, I was reading the collaborator's unpublished manuscript out of interest. I felt that some parts were uncannily similar to certain sections of our paper, checked back, and confirmed that they were exact to word. Second time, the collaborator's student alerted me to it and sent me an unpublished paper from his lab. Same process of discovery, I read the paper and identified another twin paragraph. By this time, I am pretty sure that most of the stuff Prof "wrote" was a patchwork of paragraphs borrowed from collaborator. I don't know what to think. In my undergraduate years, I was taught that this constitutes plagiarism. My work ethic and values about writing and research are in distress.
2. I found out that the collaborators thought Prof was doing most of the work - the analyses, writing, additional analyses, and edits (> 20 drafts of the paper) based on their numerous email exchanges. What actually happens is that Prof copies and pastes the requested edits in his email to me, asks me to finish by the next morning, and sends it off after dropping me a word of thanks. I never saw any of the edits he claimed to have done, and he has never handled anything related to the writing or analyses of this paper on his own.
Hmm....... Redditors of AskAcademia, what do you make of this?
| Contact the right administration department and let them know your concerns. Between the authorship claim and plagiarism, your PI isn't fit for academia and you can find a bettor mentor. Change labs (maybe even departments). | 72 | 73 |
I don't think anyone should get extra time in an exam. CMV. | This may not exist in some exams, but in the high school exams that I took (the IB), some students were allowed extra time for things such as: dyslexia, ADD, etc. Now before you think I'm a complete ass for essentially harming people with those conditions' future by not allowing them to perform to the "best" of their abilities (quotations will be explained later), here are my reasons for thinking as such:
In my view, an exam should assess a person's ability to absorb and process information in a manner suitable for the exam (for example: in math or physics exam, to be able to solve problems quickly and correctly). I think the exam should be used to distinguish between candidates for university, or a career. As such, I think that the time allocated is a rather large factor: if you have more time to absorb or process the information, you may eventually get it. But the point is to distinguish between person A and person B for a position.
Given an infinite amount of time, I would say more people would be able to get 100% on an exam, which then defeats the purpose of taking one unless your aim was just to have a confidence booster.
Now, I also think that when applying (let's take the example of applying to university), these conditions should be considered: the admissions officer should know that your exam result may not be completely reflective of what you could do given a lot more time. But in the context of an exam, I don't think its about measuring your best abilities when given infinite time. The rate at which a student can absorb and process the information should be compared. This is why I put quotations around ""best" of their abilities". Of course they could do better with more time, but so can everyone (a generalization, I know: I recognize that I cannot say that all can answer every question correctly in an exam).
Now the reason I care is that the exams are graded on a curve. If you compensate for a student's difficulty in reading by providing them extra time to raise their grade, it will (if enough are given more time) affect everyone's grade. It also doesn't tell the admissions officer what you can do in the time given normally in an exam, compared to another student. It defeats the purpose (in my opinion) of a standardized exam.
As well as this, I am a little skeptical as to the ability of the examiner to determine exactly how much more time would make the exam "fair".
Yes, it sucks that a person has this condition. Yes, I think it should be compensated for, or at least considered. No, I do not think that giving extra time in a standardized exam graded on a curve is the way to do so. I think it's like having a race between Pistorius and Bolt on the 100m, and giving Pistorius extra time. Then, taking that result into account as an average to determine who is the fastest runner. Again, I'm sorry for Pistorius to have a natural disadvantage (although I do not claim to be an expert in whether this provides disadvantages but I just compared best running times), but I don't think he should be given extra time due to his condition.
TL;DR: I think extra time in an exam is like giving a legless man a head start in a race with Usain bolt until he almost beats him, then considering this a good comparison.
PS: Let me know if my explanation isn't that good, or is missing some logical connectors. I'll try and clear it up to show exactly what I think.
Edit 1: Wow this has become bigger than I expected! Thanks so much for all the contributions: it's fascinating to read these comments. A common theme I'm seeing among the answers is now the disagreement on what exams test (which I should have clarified earlier): Some, like Sabazius, Dr_Wreck, and sarcasmandsocialism, seem to say that exams usually should not include how fast you can answer, or rather, as Sabazius said "the quality being tested was a student's ability to perform in a given amount of time". I actually do think so. In this case, as many explained better than me: the condition does affect a part of the aptitude being tested. So giving extra time does not level the playing field, but rather distorts results (which was what I tried to explain earlier). In this case, how does my opinion hold up?
Edit 1.5 (super quick added edit): Another thing I've noticed is people pointing out that I seem to be not thinking outside of the school world, and not taking into account the fact that exams aren't perfect for demonstrating how good someone would be in the real world. This is partly true (I do sometimes get a little stuck in the school world) but I also think that exams both do a fairly good job at emulating the real world in a period of time, and at the moment seems to be the only viable way to compare aptitude(and realistic: ideally one would interview each person for a long time to figure out how apt they are but that's a bit time consuming/expensive). Yes, they aren't perfect, but I don't think that extra time improves the system. | The primary purpose of testing is to see if a student understands something, *not* to see which student can answer fastest. If a student has dyslexia and takes a long time to understand the questions, limiting them on time means that the test is no longer measuring their subject comprehension, it is measuring their reading speed.
The reality is that subject comprehension is far more valuable for most jobs than the ability to provide written answers to standardized, written questions while sitting still for a specific amount of time. In real life, there are many ways students with ADHD or dyslexia can adjust their environment to increase their productivity, but those are impossible in the artificially controlled testing environment.
tl;dr Tests should primarily measure subject comprehension, not the ability to take a written test. | 267 | 187 |
ELI5: How is it possible for dinosaur footprints that are hundreds of millions of years old to exist at the bottom of a riverbed without being eroded away by the water? | Many parts of Texas are experiencing severe drought (though not quite as severe as the b\*tch that was the 2011 drought). As a result of these exceptionally dry conditions, a certain riverbed in Dinosaur Valley State Park has run dry, exposing previously undiscovered dinosaur tracks that are roughly 113 million years old. How is this possible—like, how have they not been eroded by the river? Water is pretty excellent at eroding rock, especially over the course of 113 million years. On the one hand, I do understand that most likely the river has not been there as long as the dinosaur tracks have been, but on the other hand (1) we actually don't know this for sure, and (2) even if it has been there for less time than the tracks have been, there certainly has still been ample time to erode them away. What am I missing here?
[https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjWsazb4t\_5AhXRk2oFHVUIBawQvOMEKAB6BAgGEAE&url=https%3A%2F%2Fwww.cnn.com%2F2022%2F08%2F23%2Fus%2Fdinosaur-tracks-discovered-texas-park%2Findex.html&usg=AOvVaw2co9awHFuiD-qAeMOP5DNk](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjWsazb4t_5AhXRk2oFHVUIBawQvOMEKAB6BAgGEAE&url=https%3A%2F%2Fwww.cnn.com%2F2022%2F08%2F23%2Fus%2Fdinosaur-tracks-discovered-texas-park%2Findex.html&usg=AOvVaw2co9awHFuiD-qAeMOP5DNk)
*EDIT/UPDATE: Aha! It now makes sense. It turns out that these particular dinosaur tracks were first discovered in 1908, when a layer of rock that had been covering the tracks broke up and washed away due to a flood. In the time since then, there have been multiple paleontological excavations that have revealed even more of the tracks. And the most important thing to know here—the thing that ties it all together and makes everything "click"—the River* ***has*** *been eroding the prints ever since the first tracks got exposed in 1908. It's just that obviously on a geological timescale, the 114 years between 1908 and now are just a tiny, minuscule blip in the grand scheme of things... nowhere near long enough for the tracks to have been eroded. So it all makes sense, knowing that the river has only been eroding the tracks for 114 years instead of 113 million years.*
*Source:* [*https://www.nps.gov/.../nature/making-dino-prints.htm...*](https://www.nps.gov/dena/learn/nature/making-dino-prints.htm?fbclid=IwAR3MZ-SQHiJg8uZ7LEjeSZTNgE705yDE4x54VFmrHZgGdySHhI5kLdXgcO4#:~:text=When%20dinosaurs%20walked%20through%20the,where%20people%20can%20see%20them) | 1) Step in soft mud to leave a footprint
2) Footprint in soft mud dries into kinda hard clay
3) Kinda hard clay gets covered by other soft soil. Lots of soft soil.
4) Soil compacts for a few million years and and the kinda hard clay turns into very hard rock
5) A river shifts and begins to erode an area.
6) Erosion takes away any soft and kinda hard stuff, exposing the footprints that are now in very hard rocks. | 2,632 | 1,549 |
Humans can easily identify other humans using their faces alone, but we generally can't easily distinguish one member of a species from another by face alone (e.g. a lion from the others). Do animals have the same ability to recognize each other (same species) from face alone? | Good question, some animals are capable of face recognition, such as Chimpanzees. To humans most chimpanzees look the same, although chimpanzees can distinguish each other by seeing each others faces most of the time. Some other common methods animals use to distinguish each other are by smell and sounds. | 116 | 242 |
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ELI5: Why does the US have a high gun ownership rate and a high gun violence rate and the Swiss have a high gun ownership rate and a low gun violence rate? | The Swiss also have mandatory military service and a relatively low income gap, with universal health care and a more robust welfare state. So less of the desperation that leads to violent crime combined with knowing everybody has a gun and knows how to use it would logically result in in a low violent crime rate. | 39 | 21 |
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ELI5: Why aren't there many engineers or scientists in congress/politics/government? | I get that people think differently but why isn't there an effort for this? I DO believe there are SOME issues that engineers would solve/attempt to solve better than current politicians. | Engineers do what they do generally speaking because they like to solve problems. Engineers design better things, fix broken things, make things more efficient. Making an engineer work in government would essentially be putting him into some sort of engineer-specific dante's circle of hell. | 25 | 21 |
ELI5: Why are judges given discretion in deciding penalties for crimes? | In theory, to make sure the punishment fits the circumstances surrounding a crime.
If someone robs a convenience store because their kid needed lifesaving medical treatment and the person genuinely appears to feel terrible about it, yes he still deserves to be punished. But, most would argue he shouldn't serve the same sentence as someone that did it because they're a sociopath, and generally acted like an unremorseful dick.
It's basically impossible to codify all the potential variables in a case into law, and the law's complicated enough as it is. | 38 | 22 |
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ELI5:There are warnings on my microwave that say not to run it while empty. Does anyone now why or how this damages the microwave? | The walls of the oven are designed to reflect the microwaves, intending for them to eventually be absorbed by food. But with no food, they will just keep bouncing around, eventually being reflected back at the magnetron, heating it up. The excess heat can damage it. Best case is that it blows a fuse, rendering the microwave inoperable until it's replaced. Worst case is it gets so hot to cause something like the insulation to burst into flames. | 79 | 118 |
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CMV: Successful people from humble backgrounds have had to work harder, and so deserve more respect than those with well-off families. | In my view, people who were born into well-off families, and who subsequently become successful, for whatever reason, don't deserve the same amount of respect as successful people who come from more humble backgrounds. It's always struck me that most of the time, that former type of person has never really known, and likely will never know, hardship - and even more likely, won't have had to work as hard to get where they are as those whose families have less.
Let's illustrate this idea with the current US President, and his 'small loan of a million dollars' from his dad (which, with inflation, would be more like $70 million nowadays). He wouldn't have got where he is today without his family's fortune. He's had a silver spoon in his mouth all his life - how can he truly understand what Americans who are struggling are going through?
Speaking more generally, let's compare their childhoods. The majority of well-off families are going to want to send their kids to the best schools they can, and good for them: after all, most parents just want the best for their kids. Said well-off families are also going to be able to pay for extra tuition if their kid is struggling, music lessons, and so and so forth. Meanwhile, the less well-off families, who in many cases will also want the best for their offspring, would no doubt want to try and get their kids into good schools - but for various reasons (catchment areas, financial barriers, rigorous entrance tests) that just isn't possible. Same goes for the extracurricular stuff - unless it is subsidised, for many working-class families, that sort of thing just isn't feasible.
It's the same story at university level (a.k.a college, if you're American): kids with rich parents are able to take full advantage of uni life; for example, they won't need to take a part-time job to fund studies/living costs (on a side note, in the UK, our student loan is basically a graduate tax which is written off after 30 years, so it's not quite as bad as in the States). They'll probably be able to pay for textbooks/study materials, foreign trips and all the rest of it. Conversely, the poor kid is going to struggle to pay for a lot of this without a job and/or significant financial assistance (in the UK, at least if you're dirt poor, I understand the latter is actually quite decent for students).
Then what about those who move to big cities (London, NYC, LA, etc) to try and 'make it' in whatever industry (i.e. the media/showbiz, finance, creative industries, to name but a few)? The rich kid is inherently going to be at an advantage, because their families can financially support them; meanwhile, the poor kid is at best going to have to take a job in order to cover (if they're lucky) the high living costs in such cities. The rich kid can take unpaid internships, some of which are necessary for certain industries (the media is fairly notorious for them in the UK); for the poor kid, these are basically off-limits. Just how is that fair?
This is why I have so much respect for those who have made it from nothing - as trite as this may sound, they've had to go the extra mile in order to get where they are; meanwhile, someone at a similar level who had many hands up in their life hasn't had to work nearly as hard (even if, in their minds, they've worked exceptionally hard). What have they done? They've had help from Mummy and Daddy all their lives. It seems like nothing they've done has been entirely off their own backs. They were born rich and will probably die rich, never truly understanding the struggles of those worse off than them.
I realise much of this post will likely come across as inverse snobbery, and to be fair, it probably is. It is also, however, a view I have held for some time, albeit one which I realise could do with being challenged.
TL;DR: Successful people from more humble backgrounds deserve much more same respect than successful people from well-off background, because the former will have worked much, much harder to get where they are; meanwhile, the latter will usually have had a lot of help from their families. | You’re right people from humble backgrounds have most likely seen more hardship and worked harder. But why does where you’ve come from decide how much respect are given?
What if successful person from a humble background has children, maybe their hard working attitude rubs off on the kids and they achieve success too. It may have been easier for the children than the parents but is that really a bad thing? It doesn’t mean they didn’t work hard or try their best or that they deserve less respect for what they’ve achieved. Does that mean no one who plans on having a family should strive for success so that their children can learn about hardship?
IMO respect should be more about how people treat other people than the career they have and just because someone came from a more privileged background doesn’t mean they don’t share the same values in life or deserve the same amount of respect.
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Advice on how to include or document code into a dissertation | Hi, the core of my dissertation is not coding. However to do all the studies I had to write a series of scripts to handle the data for either visualizations or any sort of analysis. For the niche group of researchers in this topic, we consider these pieces of code could be useful. So, besides including a github repository with mys scripts, could anyone share tips on how to include this type of work? Is it an appendix the best alternative? Or is this worth a chapter? | Apart from the appendix, which is a good idea, you can also create project for your dissertation on Open science foundation or Zonedo and link your GitHub repo, to make it more visible for researchers. | 15 | 17 |
First time giving a long (45+ minutes) presentation on my research - What to talk about? | Hi everyone,
having been a graduate student for quite a while now, I have given quite a few 20-30 minute papers that give a general introduction to my research. What I normally did (I am a graduate student in history) for these short talks, is to first shortly introduce what my topic is, talk about the past literature shortly and what is new about my research, then discuss the themes that run through my dissertation and then focus on the most important aspects in terms of content that I focus on, before closing with the conclusion.
However, in a few weeks I will have to give a longer talk about my research for the first time (I was asked to speak for between 45 and 50 minutes) and I am not too sure what to focus on. The audience will be rather general, so not specialists in my field. Currently I am thinking of keeping the structure of my talk, but extending the last part (the content bit) further with a few more stories and by going a little more deeply into what I do in my dissertation, mainly as I always felt that I wanted to say more about that in previous talks and because I think that would be of greatest interest to the audience. But I am wondering what other suggestions people might have as to how to structure a longer talk about one's research?
Thanks. | When you're speaking to a more general audience, you can / should spend some time elaborating on the context in which your research takes place, and also a bit more time explaining why what you did / found is important within that context.
So expand on your background discussion to help people unfamiliar with your subject gain enough familiarity to follow your research, and then spend a bit more time near the end explaining *why* that work is important, and why what you found is relevant within the context that you established during the earlier part of the talk.
Also remember that slides should be pictures, not text. Text bores the shit out of general audiences. Find good-quality pictures, or create good-quality graphics, or both, that emphasize your points and give people something to focus on when you're talking. | 13 | 19 |
How did academics do literature review before the internet? | My first thought was libraries, but that still sounds crazy | There's a great book by Umberto Eco about how to be successful in grad school - he wrote it for his own graduate students because he was tired of giving them the same talk every time a new cohort started. He describes going to the library, going through the catalog and writing down the bibliographical reference for the texts he wanted on individual note cards. Then he'd go find all the texts, take his notes on the note-cards and then keep them in an ever-increasing collection in his office.
​
So - yeah, as everyone else said. Libraries. And note-card collections. | 146 | 82 |
[Zootopia] Why isn't Officer Hopps concerned about the buying of fur rugs... in a world where animals are sapient? | After the question about her continued association with people who have a murder pit, I realized this-- the skunk butt rug bit was played for laughs, but... it's still a fur rug *in a world where animals are sapient!*
Isn't this like selling someone a rug made from human back hair instead of scalps? What poor skunk had his butt taken for the rug? And why isn't Officer Hopps concerned about this? | Animals can provide their fur and wool to be used in clothing and furniture.
High-end wool, like from alpaca or angora, can be sold for top dollar. Most other animals have to settle for bargain rates and so usually only the poor resort to selling their fur. And then there is the bottom of the barrel hair, like from muskrats or skunks.
Those with undesirable fur have to donate it because no one will purchase it willingly. Charitable organizations will take donated fur and weave it into useful textiles to be given away or sold at discount rates.
A welfare recipient or college student might be desperate enough to pick up something like a skunk-butt rug, but most Zootopians can afford better. | 106 | 173 |
Learning Philosophy vs reading Philosophers | Is reading philosophers important at all? And if so, how much?
In context I ask because if we want to learn philosophy and use it as a way of figuring things out and thinking about the world better then how important is reading philosophers work as opposed to just learning philosophical skills. For example I am interested in the idea of personal identity so I find it interesting to read David Hume and Buddhist works but are these for me to use philosophical techniques and neuroscience etc to try and figure out the concept of personal identity and whether it even exists at all? We study logic so that we can spot whether an argument is valid or invalid, and if valid is it sound. But we don’t need to read any philosopher to learn this skill, except for the one who wrote the curriculum. The skills of philosophy allow you approach any subject better, whether philosophical or not. So if someone is interested in learning philosophical skills as a way to approach things then how important is reading the works of philosophers? | So you want to learn to philosophize, or more exhaustively, you want to learn how to use the tools and methods for reasoning to arrive at generalized statements of some truth value, about topics that empirical study won't yield meaningful results. How do you do this? By practicing these skills in some manner. People have been doing this for ~2300 years already, though. Do you set out on your own, and build up your skills from the ground up, or do you take advantage of the fact that there is ~2300 years of work on this subject to use as a guide?
If you try to build your own system from the ground up, you'll probably make some mistakes and errors, and the chance is that someone in those intervening thousands of years made those same mistakes. So learning to philosophize by learning about the theories of past philosophers is beneficial for at least three reasons: you get to see examples of philosophizing done by experts, you can correct certain errors and pitfalls you would have made on your own by seeing how past thinkers have run into those problems and corrected them, and you can see how *not* to do things, based on errors or holes in their reasoning they did not correct.
Many subjects are taught like this. In art you study and copy works by the masters before you can break the rules and forge your own path, in music you learn the compositions of great composers before you can compose your own pieces, etc. | 32 | 25 |
[Portal] Aperture Markets their products to Modern-Day Earth! | **This deviates from canon slightly. We're going to have Aperture be founded somewhere in the 1990s instead of in the Half-Life universe during the 40s, as well as Cave and Caroline being alive and GLaDOS never being built.**
*Fact: Aperture is the best damn applied sciences company on Earth and it's testing program is a huge success.*
*Fact Two: Aperture is an inefficient and expensive company that has such craziness like packaged turrets and panels being unwrapped within minutes to be put in chambers.*
*But what could they do to improve this?*
*Simple - Gain some competence. Take their many technologies, fix some of their safety problems (like the Portal Device being prone to implosion, energy pellets being agitated by alarms and hazard lights, and repulsion gel not liking the skeleton) and start selling them for multiple uses including industry and recreation.*
*There's a big stack of liability waivers still on them, but I'm sure they all have SOME use to the people of Earth.*
***Aperture now sells the following technologies in stores globally.***
**Propulsion and Repulsion Gel**
*Two easily washed-off gel substances. One increases speed immensely, the other causes things that touch it to bounce off. Repulsion Gel can also be safely walked across if you brace your landing or walk onto it rather than falling from a height.*
**Conversion Gel**
*A third, special Gel that lets Portals be placed on surfaces that usually do not accept them. Expensive due to using Lunar Basalt in it's mixture and dangerous for people allergic to Moon Dust.*
**Storage Cubes, Companion Cubes, and Edgeless Safety Cubes**
*Cubes. Well, one of them is a sphere. You can presumably, well, store things in them. Compatible with most Aperture Tech as well.*
**The Handheld Portal Device**
*It's a 'Portal Gun' that creates two completely safe physics-defying holes in spacetime and works best on flat surfaces painted white or made of tile or concrete, or lunar soil. Bundled with Long Fall Boots for safety reasons.*
**Panels**
*Infinitely variable 4ftx4ft Robot Arms that can completely transform a room.*
**Excursion Funnels**
*Turbines that produce a gravity-defying tractor beam of liquid. Their polarity can be reversed.*
**Aerial Faith Plates**
*Catapults for rapid propulsion of objects. Also sold with Long Fall Boots.*
**Hard Light Bridges**
*Bridges made of solid natural light. Require a massive array of solar panels and engines, but work reliably.*
**Personality Cores**
*Arguably alive sentient eyeball bot with many uses. Comes in an array of personalities.*
**Thermal Discouragement Beams**
*Lasers. Hot to the touch but can be used for industrial cutting or for powering objects. Comes with a Discouragement Redirection Cube, which lets the beam point in different directions.*
***The following are also sold, but to global military powers under a defense contractor sub-brand.***
**High Energy Pellets**
*Powerful plasma orbs that can be used to power things but are dangerously lethal to any organic matter that makes contact. Have a short lifespan.*
**Sentry Turrets**
*Egg-shaped Fusion-powered Robots that fire a seemingly endless supply of NATO cartridges out of an ammo box at a high rate of speed. Presumably programmable not to shoot at certain individuals.*
***What are the global short-term and long-term effects of Aperture products being sold in stores?***
*Bonus*: The same scenario but with no Portal Device or Excursion Funnel. | Both short and long term? The global economy crashes from Portal tech due to the elimination of need of the logistics to move freight across the globe. Middle East breaks out in war as the oil nation economies collapse. Russia invades EU as to starve off its inevitable collapse from losing oil income. USA deploys the national guard as millions of truckers, sailors, and others riot from the job loss.
[Spoiler: The Handheld Portal Device](#s "Only works on moondust, which were what the panels were painted with.") | 24 | 53 |
ELI5 How did they manage to get big ships docked before the invention of motor engines ? | The first thing to do is wait for the right weather. You anchor outside the harbour or sail around until the wind is of the right strength and direction to allow you to get in.
The next thing to do is take on a pilot, this is someone who knows the harbour intimately and so where to turn, where to avoid shoals etc. You pick them up out at sea where there is space to do so.
Then you sail into the harbour and up to a quay. You need to control your speed by adjusting and taking in sails so that you berth slowly. This is quite within the capability of a skilled skipper and well drilled crew.
Then if you need to move the ship to another basin, another quay, turn it around etc then you warp it around, which basically means pulling it about using ropes. You might have mule teams to help, certainly you use capstans on the ship and ashore.
Steam tugs were used long before ocean going cargo ships were powered by engines. They could help manoeuvre the ships into tight spots, or tow them into harbour in calm weather.
All of the same techniques are used in modern shipping with modern ships, in fact modern ships are arguably harder to dock given how much larger they are. | 152 | 91 |
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Dear scientist redditors, does decanting wine actually do anything? | I got a wine aerator for christmas and have failed at blind test to see which glass was aerated. Though it usually tastes different to me when using a decanter, i realize this might just be confirmation bias or the placebo effect. Please help me, am i wasting time/dishes by decanting, or am i just not skilled enough yet to tell the difference? | Not all wines will be dramatically affected by decanting, but those with a significant amount of tannins will change in flavor very significantly. The decanter increases the surface area of the wine, allowing it to be aerated much more quickly. The aeration causes the tannins in the wine to become oxidized, which changes the astringency and aroma of the wine.
Again, not all wines are improved by decanting, but very few are damaged. | 30 | 19 |
Do all wavelengths of the electromagnetic spectrum travel at the same speed? | I keep hearing speed of 'light'. This made me wonder if it is visible light that is being referred to or just any type of electromagnetic radiation? | Many of the answers so far correctly state that the speed of light *through vacuum* does not depend on wavelength. In materials, however, this is not the case. In matter, different EM wavelengths will propagate at different speeds, this effect is called dispersion.
The two parameters that govern the speed of light are the electric permittivity (epsilon) and magnetic permeability (mu) of the medium the light is traveling through. *You can loosely think of these two parameters as describing how much the medium resists changes in the EM field*. The vacuum permittivity and vacuum permeability are not dependent on wavelength, and so the speed of light *in vacuum* is also not dependent on wavelength, and so all colors of light travel the same speed in vacuum.
**However**, when light travels through a material, the speed of light *does* depend on wavelength (though we should really be thinking in terms of frequency, with the understanding that wavelength and frequency describe loosely the same attribute of the optical wave). Materials are made up of charged particles which can interact with the optical wave that is traveling through the medium. Remember, electrically charged particles have their own electric field and will be pushed around by the electric field of the optical wave, this impacts the electric permittivity and magnetic permeability of the material, so the speed of light in a material will be different than the speed of light in vacuum (since there are charges that the EM wave can push around as it travels through the material). You can think of each electron as being attached to springs - the incoming EM field can then interact with the electrons, pushing them back and forth. Continuing with this analogy, the speed of the EM wave depends on how 'stiff' the 'springs' are. In reality, the 'stiffness' is simply the electric permittivity and permeably of the material. These two parameters depend on the material, as well as the frequency of light - that is, a low frequency wave will drive the electrons back and slowly while a high frequency wave will try to drive the electrons back and forth faster (sometimes so fast the electron's don't follow the EM field very well).
The index of refraction of a material is related to the permittivity and permeability of that particular material. More commonly, we use the index of refraction to describe how fast light travels in a material. The phenomenon you describe in your question is called *dispersion*, which is essentially wavelength dependent index of refraction. All materials have a dispersion curve which shows the index of refraction as a function of wavelength for that particular material.
**Edit**: if you treat each electron as a harmonic oscillator being driven by an external force, you see that the motion of the oscillator depends on the frequency of the driving EM field. Since the electrons are being driven by the incident wave, they themselves create an EM wave. In fact, using this model, the incident wave is absorbed and the wave that propagates through the medium is a result of how the electrons move - which is frequency dependent (it's also dependent on the shape of the potential well the electrons find themselves in due to their neighbors).
| 29 | 38 |
[Economics] Hypothetical: The dollar crashes on Monday. What happens? | I'm interested in deep analysis of this, though obviously a hypothetical is always speculation.
* What's the likely time scale?
* What would the government do to try to mitigate?
* What happens to the average family in the US? (middle class, specifically but upper and potentially lower class too)
* How does daily life change? Like would we potentially be in danger of losing utilities and creature comforts like power, running water, internet, gas, phones, etc?
* What happens with other nations?
Thanks in advance for the insight.
Edit:
In response to the valid point / question that /u/ALoudMouthBaby brought up [here](http://www.reddit.com/r/AskSocialScience/comments/1c61kz/economics_hypothetical_the_dollar_crashes_on/c9ddqux), it is highly dependent on what caused the crash. Of course nobody can know the answer to this; but just state your assumptions in your answer. | Time scale for what? And all of these are pretty heavily dependent on what caused it.
A theoretical like this is kind of ridiculous though since it would take a massive global crisis for the dollar to actually crash. It's not like it's BitCoins. | 11 | 19 |
I believe capitalism is a detriment to society as a whole. We will never be a thriving society with it in place. CMV | Capitalism is the primary reason for the lack of advancements in energy, medicine, housing, poverty, world peace, the drug war, ect... It causes a "me vs. you" mentality, resulting in crime committed by, desperate people trying to survive or the sociopaths who are allowed to use there viciousness to succeed in the corporate world. It induces insane greed in those who succeed with it, causing CEO's and others to put profits before humanity and nature. And it is so out of balance these days that small businesses, mostly, don't stand a chance of success against the marketplace titans. It is a broken system and it's literally killing us. Convince me otherwise.
Edit- I'm writing "edit" this because I guess I wasn't too clear in my argument. (forgive me, I am new to the debating type subreddits) Okay, so it would take a long long time to cite every occurrence for the detriment reaches far and wide but I will speak from my observations and cite a few things.
- We no longer have products that last a life time because disposable shit make a company more money.
- L.A., California lost it's effective subway system to oil, tire, and car companies(look at the smog problem)
- Monsanto destroys some farmers who do/and most farmers who do not buy there products.
- Walmart destroys small businesses buy providing similar product for cheaper by buying shit products from overseas.
- Most medicine (physical and psychological) is based on systematic cures rather than fixing the root of the issue.
- Hemp can solve a lot of issues and why is that not being used? (timber, oil, pharmaceutical, ect companies)
- We(the US) are constantly caught instigating conflict in other countries for profit(directly or indirectly).
- Collecting rain is illegal in some places and so is seed trading among farmers.
- ect ect ect
I believe a socialist democracy with community service based incentive programs would work. If you want more you work towards your community and receive more. It's a very raw idea. I can go more into detail if ya'll would like.
How many times throughout history have we been stifled because the rich used their power to prevent an advancement in the name of profits?(like with tesla for example) The only reason we are advancing nowadays is because humanitarians are able to put their contributions into the public without relying on mainstream media to promote it. Corporations/central banks run the world and it's because they are given the format to do so.
We have had people attempt to come up with alternatives to the whole, you need us for this, and they are snuffed out by big business. And do I really have to cite all the times big businesses have poisoned the environment because it was cheaper? The format of business is corrupt and demands a dog eat dog mentality that makes it so you have to take advantage of any one weaker than you or you don't survive.
Do you really think I have no argument? There is something very corrupt about how this system works. It always comes down to the whole idea of the strong overtaking the weak.
"Oh, but they need us." What the hell happened to self-sufficiency? It was eliminated by big business's good friend, advertising.
I may come off like I have a blind belief but I pay attention. Most everything that we have available to us today, we only have because someone found it profitable.
Edit- Also, we have more people than jobs. So much so, that we literally have to make shit up so that people can make money to feed their families. And because we can not make enough jobs for the people who need them... People starve.
Why don't we automate to stupid stuff- trash, retail, grunt level factor work, ect, and eliminate the, work or die structure. **I do not believe people will cease to be inventors, police, doctors, teachers, ect. The important jobs are mostly done by people with passion. For those who aren't, would you really want a doctor who's in it for the money to be put in charge of finding the best chance of curing your disease or or the guy(or girl) who decided at a young age that they wanted to help people? This question applies to all the important occupations.**
Capitalism does not allow humanitarianism. It defeats it. How will we have non-corrupt globalism? Please tell me how will we thrive in the future when corporations and central banks own everything?(oh wait...)
Edit- I am convinced. My issues are valid but the cause is not Capitalism as a system. And socialism certainly is not the answer. Corrupt government and lack of regulations seem to be the major issues here. Ya'll changed my view. Deltas will be appropriated later, as I am currently headed out the door. | What lack of advancements in energy, medicine, housing, poverty, world peace, crime?
We have lots of advanced energy tech, houses, ways to address poverty, the world has never been more peaceful, crime is dropping. | 47 | 32 |
ELI5: Why do certain drugs make your pupils change size? | Pupil change is due to two muscle groups-- the iris sphincter (contraction) and the iris dilator (expansion). The sphincter response is linked to the parasympathetic nervous system, activated when we are in a relaxed state. The dilator response is tied to the sympathetic nervous system, involved in the fight-or-flight response.
Drugs which activate these systems will cause their typical impact on pupil size. For example, when someone consumes MDMA they are activating their sympathetic nervous system, which triggers the iris dilator to widen the size of the pupil. In contrast, a drug like heroin, typically known to cause a relaxed state, will activate the parasympathetic nervous system, thereby triggering the iris sphincter to contract the pupil. | 19 | 32 |
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ELI5: How can someone wake up from a brain injury and suddenly be able to speak a foreign language? | I just read this article about a man who was in a car accident and when he woke up he could fluently speak French. How does that happen when he didn't speak any french at all prior to the incident? | When this has been reported, what is often glossed over is the fact that these people could always speak the language. The brain learns and stores your first language differently to your subsequent languages. So it's possible for the first language to be lost or suppressed independently of other languages by certain brain traumas. When this happens the first language will usually eventually return.
"Woman wakes from coma speaking French" is much more dramatic than "Woman who could already speak both English and French wakes from coma having difficulty with English but French is ok but the English comes back in a day or two."
Believe nothing you read in the Huffington Post. | 1,450 | 724 |
CMV: It is invasive, ineffective & condescending to determine the validity/relevancy of a person's views based off their sexual inclination, sex or gender | I am going to try to be as clear as I can. I'm having trouble finding the best words for my thoughts & feelings. Broadly speaking among some left/progressive leaning individuals (aka "peeps") there is an idea that being part of a certain group can make your opinion more or less valid depending on your relation to that group.
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I think biological sex & the way people self-identify gender wise is a good example. If there is an issue affecting LGBTQ (& whatever else may be recognized) people it's common for "peeps" to say lgbtq voices should be "heard the loudest" or that cis/straight people should be more accommodating/lenient in conversations or debates about the topic.
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Now I follow the logic of those most affected by something would have a good insight on it but usually that isn't implied inversely, just because someone isn't directly affected by something doesn't mean they can't have an insight into it. Minimizing voices of people not directly affected by something could lead you to very suboptimal results than you would have otherwise had.
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The line of thinking these "peeps" follow also forces the hand of people who aren't "out" or "public" if they disagree with the current view being advocated for by the let's call it the "general public opinion held among the most notable or vocal of a group" . If the "peeps" assume based off the non-public/out person's appearance &/or demeaner that they aren't part of the relevant group they will dismiss or downplay the opinion of someone they otherwise wouldn't. Further limiting possible contributors to a solution.
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I would be happy to expand on anything obviously but I think if I try to give more examples I'll just muddle it up too much. | >If there is an issue affecting LGBTQ (& whatever else may be recognized) people it's common for "peeps" to say lgbtq voices should be "heard the loudest" or that cis/straight people should be more accommodating/lenient in conversations or debates about the topic.
What this really stems from is really that there's a lot of history of, for instance, straight people telling gay people what being gay is like. Straight people telling gay people what they should or should not find offensive, if they have or have not been discriminated against, how they should or should not feel or what they should or should not want. In all these types of situations, LGBT voices should definitely "be heard the loudest", because they are normally the ones who actually know better. A straight person telling a gay person what it's like to be gay is rather absurd, after all, as is trying to trivialize or outright ignore what they've gone through.
Obviously there are some cases where this line of argument gets abused ("If you're not gay you are not allowed to have an opinion on this topic") which is of course absurd, and no one can pretend that this does not happen. But those types of "shut down" arguments exist on all sides - this is hardly worse than straight/cis people attempting to declare that LGBT people are mentally confused and that society should not indulge in their lunacy. Threads about that pop up here pretty frequently, even. More often than people are told to shut it because they're straight, probably.
So in essence, yes what you are saying *does* happen, but it's not more common or worse than the same type of invalid/bad arguments made from other sides or groups in any other context. If you, as a straight/cis person is faced with such an argument, it could be pretty good to take a step back and consider if you aren't actually putting words in the mouths of LGBT people, saying incorrect things about them or anything like that. By all means, if you think that your argument is still perfectly valid and should be made, then go ahead. But there are a lot of situations where these arguments do make sense. | 15 | 17 |
CMV: the American presidential election would be a lot more fair and reasonable if we voted based on policy rather than people. | Title kinda says it all, but elections are generally popularity contests. Prior to the last several elections (and the current one), videos came out where voters were questioned on how they feel about certain issues; gay marriage, welfare, corporate bailout, taxes, trans rights, etc. Several people said they agreed with one set of views, then said they were voting for the candidate that represented the *opposite* views.
If the polls said a list of issues rather than a list of names, people would vote for what they believe in rather than for a personality or for an "image."
I understand the idea of having a specific person repping the country on the world stage, and one can even say that's half the job. But that could be offset by including foreign policy on the polls. | The results of the Trump administration’s response to COVID-19 will be one of the biggest factors by which it’ll be judged.
Did we ask Hillary and Trump their policy preferences for pandemic response? Would there have been any difference in their answers (e.g. “over 180k deaths”)?
That’s why you have to look at the person — both to understand how their values will guide their response to unforeseen disasters and to judge the level of competence they’ll bring to that response | 46 | 158 |
The income gap between white people and African Americans has not changed since 1983. What are possible ways to reduce this gap? | [Using this as reference](http://blog.metrotrends.org/2013/08/racial-wealth-gap-wide-1963-remains-large-today/), what are proposed methods of improving the standard of living of black people?
| If you're going to talk about an income gap, you should also talk about cost of living as that varies across locations, as does location of persons by racial identity. Talking about an income gap when you do not account for cost of living doesn't contribute anything meaningfully.
In standard urban models of population location and migration, wages, rents,and amenities are included (see Rosen, Roback, 1982 1989) and following literature.
| 11 | 40 |
CMV: I think the modern-day American working lifestyle is a never-ending cycle of unneeded stress and needs to change. | I really can only speak as an American citizen who works in corporate from 7-5PM. From what I can tell, and this is not a new sentiment, however daily life for the average middle class working person is monotonous and habitual. You wake up early to go to work; sit in an office where a good chunk of the people are actually just being as minimally productive as they can be to get by, just to go back home on their hour commute. 2-3 hours to yourself only to sleep 8 hours and do it all over again.
The working culture that I have been a part of makes sense. I can understand that with people that are actually utilizing their work schedules with full productivity and enthusiasm, it's the reason our GDP and economic standing is where it is. However, I know too many people in my office alone that absolutely dread going back to work. Or are stressed out too much. Or just really don't like the system in which we address work here in this country. Of course maybe if they worked doing something they loved it would be different (That's the goal and ideal) however in reality many people don't do what they want.
Just off of the top calculations too. So at least 40 people on my side of the floor have 1 hour+ commute to work. Here is how many hours they spend in their car just commuting in a work year.
(25 working days per month x 12 months) - 10 vacation days = 290 working days in a year
290 days x 2 commuting hrs (to and from) = 580 hours spent commuting = 24 days commuting
Meaning people spend a little less than a whole month in their car just driving to work. WTF. Maybe it's a necessary evil in the eyes of a productive company, but shit I don't want to waste 41 months driving in my car until retirement. Fuck.
Not trying to complain. I think we should take a look at how other nations address their workforce and find a happy medium in-between working hard and playing hard. I like the sentiment, however I know too many stressed out coworkers.
edit: I think I've seen articles looking at European countries with a really good work-life balance, however I believe their populations are not comparable to the US' in that they are way smaller. Maybe the US has such a high population that consumer demand drives the work force, however does anyone have a proposal on how to address this?
edit: So I am not alluding to whether I am happy/unhappy at my job; I am just noting on the general mood and concensus of work culture I have had conversations with other co-workers, aquaintances, etc. I am perfectly content with what I am doing right now, however I believe that there's an inherent problem with how society views work here. Anyways, holy shit just came back from moving out my current apartment and I have a lot of things to mull over. Hopefully you guys can CMV.
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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!* | Why would the total population of a European country have a difference in whether their economic systems can work in the US? Many European countries are considerably more populous than the average state in the US, and surely each employee would be hired based on the number of customers they would have to support or number of items they would have to produce. Having a larger population means the US also has more potential workers, and with a lower average age that goes even further.
I think, more than just commuting, it's the length of the average work day and the very small amount of vacation time. Most advanced countries have a legally guaranteed minimum four weeks paid vacation for full time labourers. They also generally have a lower number of hours needed to reach full time status (35-38) have more generous benefits for parents, have benefits for students, have benefits for health care and so on.
This is a very big web of social development and it more or less demonstrates to you why a more developed country has a higher standard of living. Development should take some of the burden off of an individual person's shoulders and mane it more collective. This allows every individual to live a happier more fulfilled life, which leads to them better specializing their career to their talents and interests, having less stressed in that career, and being more productive overall.
The reason the US has such a dominant economy on paper is because we became extremely hyper capitalist to the point that the main value the average person places on a corporation is to deliver profit rather than to improve society. We pay people as little as possible, while demanding as much as possible, as quickly as possible. We also have some allergy to having high enough tax rates to ensure we have fully funded and competent social programs. It creates a lot of money in the hands of those who own the means of production, but leaves very little for the rest as the very wealthy horde their obscene means in a parallel economy of rich people investing in other rich people's ideas. That money never gets back to the community level and produces effectively a reverse robin hood effect. | 157 | 1,417 |
Why does the Planck length exist, and why is it that specific size? | The Planck length is a length you get when you multiply certain constants together in physics, why it is exactly that number is not known, just as it is not known why the speed of light is the number it is or why the charge of the electron has that certain value.
You may have heard that the Planck length is the smallest length possible, but this is not so. It is simply at this scale that we would need to have a functioning theory of quantum gravity to understand phenomena. | 12 | 19 |
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If all material is eaten, are cooked vegetables less nutritious than raw ones? | For various plants, for example broccoli, many of the nutrients are locked within strong cell walls, made of cellulose. Humans do not digest cellulose too well, and a lot of the nutrients in the cells are not available as a result.
Cooking these foods weakens or breaks down these cell walls to allow for more complete digestion. But overcooking can break down other nutrients. So cooking enough to weaken the cellulose walls without destroying these other nutrients is optimal. | 10 | 28 |
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Is there a safe way to modify the human dna? | Safe is relative as it has to be balanced against the need to change.
But generally speaking, there is no currently safe way to do that, but we do have new technology that can do that, most famous is CRISPR/CAS9.
There is too issues preventing this from being used outside very experimental setting
1) the technique is about modifying a specific sequences of DNA, but it can modify DNA elsewhere in an in expected way
2) we really are only scratching the surface on what DNA we can modify, certain genetic diseases where we know a very specific segment with a very specific error is possible to modify and that is where the tech is being used on a very limited basis, specifically treating sickle cell disease
But we are probably decades away from doing something like changing a persons eye color or making babies taller
Edit : typos | 10 | 19 |
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What are 5 essential books or textbooks every software engineer should read? | Title
Edit: Wow! Thank you for all the suggestions! | 1. The Field Guide to Understanding Human Error. Not a software book, and you'll get the idea within the first half of skimming. Still very useful and important, and doubly so when you need to tell your boss's bosses why your boss is being a counterproductive asshat that's tanking the project, not saving it. The Mythical Man Month gets an honorable mention here, for correctly identifying problems in project management, but loses on having a rather uncompelling answer to them.
2. Computer Architecture: A Quantitative Approach. This is the literal bible on processor and computer architecture. You want to actually understand how your software actually executes? This is it. This is stuff that once you learn will continue to apply for decades.
3. C Programming Language. Short and to the point, and a bit dated, but the most simple and direct introduction to both c and posix, which have largely set the framework modern computing exists within.
Past that I'd say pick two good books in a topic area that interests you. Make sure they're books that will challenge you a bit and that also offer exercises/quizs/something that lets you validate you're actually learning. | 26 | 78 |
ELI5: How does a firefighter lighting a backfire help stop a fire and how does that fire not go out of control? | When a home is on fire there are usually large sources of water nearby, like a fire hydrant, or the ability to call for tanker trucks for additional water.
Wildfires are not that way, remote often far from roads or too difficult to being large tanker trucks. So wild fires are rarely fought with water except in certain situations. With a wild fire you stop the fire by removing the fuel. Use workers with hand tools, bull dozers and other heavy equipment to clear the grass brush and trees.
Once you've created a fire break, and cleared as much brush as possible, a second back fire that's hopefully burning into the wind and not with the wind is set. By burning into the wind it's a smaller slower fire that burns all the fuel that the uncontrollable wildfire would want. So when the wild fire gets there all the fuel is already burnt and the main fire dies out. | 89 | 75 |
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[Witcher] What are all the different Witcher schools like? | Does the cat school focus on using speed instead of strength and vise versa for the bear school? Is there a best school? Does each school specify in a certain weapon? etc. | - All Witchers have the same basic mutations and training, resulting in increased strength, speed, resistance to disease, sterility, knowledge of alchemy, and an aptitude for signs. Regardless of what they focus on, any Witcher will be stronger, faster, and more skilled than all but the most capable unmutated humans.
- Different schools do appear to have different talents. The Griffon school is known for being generally better with signs. The Cat school is known for using light armor, quick strikes, and favoring speed over strength. All known members of the Viper school use short swords, rather than long swords. dual-wielding and poison use is more common for them than it is for the other schools.
- That said, Witchers are very individualistic, and it would be a mistake to prepare *solely* for the expected fighting style of a Witcher based on the school they belong to. You might prepare fortifications against a Bear-school witcher only to find they're still dexterous enough to climb the sheer cliffs at your back and take you by surprise. You might ward yourself against the signs of a Griffon School Wtcher only to blown apart by alchemical bombs your protections against magic are worthless against. | 30 | 57 |
ELI5: How do soap and shampoo clean your body? | At a molecular level, if you were to examine a molecule of soap you would see that it is not symmetrical, in fact it has two different "ends". One of these ends is strongly attracted to water molecules while the other one is strongly attracted to fat molecules.
So when you rub soap on your body, the fat-attracting end of the soap molecules binds to the grease and dirt on your skin. Then when you rinse with soap, the water-attracting part of the soap binds on to the water molecules, and as it gets washed away it carries with it the dirt and grease that it's previously "grabbed". | 59 | 35 |
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Is there an operator that can have an associative property without a commutative property, or vice versa? | It seems that operators, whether they're pertaining to numbers, sets, propositional logic, vectors or whatever, will only have an associative property (ex. (a+b)+c = a+(b+c) ) when they also have a commutative property (ex. a+b = b+a).
I can't quite put my nose on what the two properties have in common with each other; is there an abstract proof (or disproof) that they're bi-conditional, or something along those lines? Sorry if my question's not clear I'm slightly drunk and frustrated because I can't figure it out on my own. | There are plenty of operators that are associative, but not commutative. And plenty that are the other way around. Just to give one example of each:
Function composition: we define the composition of two functions from R->R, f * g as f(g(x)). Checking associativity:
(f * g) * h = f(g(x)) * h = f(g(h(x)) = f * g(h(x)) = f * (g * h)
However, this operator is not commutative. Let f(x) = x + 1 and g(x) = x^(2), then f * g = x^2 + 1, but g * f = (x + 1)^(2).
The other way around, consider the operator that takes 2 real numbers and returns the average. So a (+) b = (a + b) / 2. This operator is clearly commutative since addition is. But it is not associative. Take a = 0, b = 4, c = 2:
(a (+) b) (+) c = 2 (+) 2 = 2
a (+) (b (+) c) = 0 (+) 3 = 1.5
There are plenty of other examples that you can find for either direction, so in general it is definitely not the case that associativity and commutativity are interchangeable. | 74 | 107 |
ELI5: Why do different internet browsers perform better or worse than the other, and what makes Internet Explorer apparently terrible? | Edit: *than others, for you grammar people. | Most web content follows a standard set of rules, called web standards to tell the browser what the content is, and how it should look. Every browser runs on a layout engine. These are sets of code that open web addresses, render the contents, allow you to bookmark, etc. Most browsers (Chrome and Safari, that run on the Webkit engine, and Firefox, which runs on the Gecko engine) follow the standards pretty closely and render content the way it was intended. They also use a Javascript engine, which interprets code the web site sends to your browser to run. This uses another set of standards that browsers follow. Internet Explorer, due to Microsoft being a very proprietary company, decided that they would create their own proprietary standards, and web content would need to conform to them to look good in their browser. So for a long time there was a set of rules for good browsers, and a set of rules for IE. So basically everyone hated IE for making them maintain two sets of code. Also, their were looooots of bugs in earlier versions of IE, where, even if you followed the rules, things would be rendered incorrectly, frustrating developers even more. | 20 | 15 |
Is full labor capacity possible without runaway inflation? | Yes, as long as you have an accurate definition of "full labor capacity." Because there will always be some people between jobs, and some people with outdated skills, even in a tight labor market, "full employment" will always carry a positive unemployment rate. Full employment was probably achieved right before the pandemic.
In order to get an unemployment rate of zero, something would have to happen to cause workers to immediately choose any job available and to cause all employers to immediately choose any worker available. That's a somewhat apocalyptic scenario. | 23 | 27 |
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ELI5: Why can some businesses swipe my card without any verification(PIN/signature) from me? | There is usually a threshold set by the card companies above which a signature is required. Small purchases are less likely to be fraudulent since people with a stolen card are going to run the card up as fast as possible before it gets reported. Now that cards are more common than cash, not requiring a signature for every purchase adds convenience for the consumer and efficiency for the retailer. Security is great, but it adds more work and people are always looking for that balance. | 13 | 33 |
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ELI5: Why are we taught Math that I'll never use out of high school instead of things like balancing a check book and paying taxes? | I don't get why I'm learning how to do Algebra when I have no clue how to do any "real life" skills? To be honest I don't even know where to use this math in real life. | Believe it or not, math teaches you how to problem solve. Every math problem that we analyze forces us to use many, if not all, of the detailed methods of problem solving.
Successful problem solvers pay attention to detail, they examine all elements & variables at hand, and they stick to a plan or formula -- all characteristics that are heavily reinforced by learning and studying math. It takes discipline to learn math and it takes discipline to focus on solving real-world problems even they aren't math related. | 48 | 19 |
How do I explain the origin and nature of time to an 8 year old? | Honestly, Reddit, I'm stunned that an eight year old is able to simply understand the concept. Last week, he asked me where the universe came from. BAM! Big Bang. Where did people come from? KAPOW! Monkeys, little man. What's more, I know my explanations stuck. In stumbling for a response, his mom, my girlfriend asked him, "well, um, how do you think the earth got here? Was it god or the Big Bang?"
"You mean, like, little rocks that turned into bigger rocks that turned into bigger rocks? That way, the Big Bang."
I have no idea how to explain time, as my understanding is vague and esoteric as it is. The extent of my understanding is that time is a product of gravity, and that it is relative to speed. As a man with a background in history, I'm pretty proud of this limited knowledge, but know it's missing almost everything, and have no way of relaying it to a kid.
Besides, this will be a good exercise for anybody interested in educating people on science. If you can explain it accurately in terms that a second grader can understand, you understand it well enough to explain it to just about anybody. Just channel your inner Neil deGrasse Tyson. | Your best bet is probably time is just a way of measuring change. Explain to a kid how watching a movie is just a lot of pictures moving really fast (you can make a flip book or something as well). Time is just the difference from one frame to the next, but it is continuous.
For the rest of science get him the complete Magic School Bus series. Seriously. You would probably enjoy it yourself as it still came in helpful well into university. | 35 | 29 |
What is the difference between technician, postdoc and staff scientist in life sciences in the US | asking for a friend | Techs do not usually have a doctoral degree, though they certainly could depending on their career goals. A tech with a doctoral degree would often be employed as a lab manager with some supervisory duties, and his/her salary is entirely supported by the principal investigator (PI).
Post-docs are usually "temporary" positions lasting 2-5 years and function as additional training for individuals looking to build their independent research careers (or potentially developing a skill-set before moving to industry). By definition, post-docs have doctoral degrees. Usually this is a PhD, although MD/DO/PharmD/DVM/SciD are all possible as well. These individuals are supported by their PI, but may also apply for external funding from the government or foundations. These grant applications are for "mentored" projects, where the PI is their mentor and supervisor.
A staff scientist is usually a person with a terminal degree, as enumerated above. They often have PI status and are capable of submitting grants that are not mentored. However, they are often closely affiliated with another PI who is in a faculty role and with whom they may share labspace and equipment. It's kind of like a postdoc-plus, where you have additional independence but aren't yet at the level where a university of hospital is willing to commit the financial and physical resources necessary for you to have your own independently-functioning lab. | 46 | 29 |
Why are distant white clouds not blue-tinted? | The further away something is, the bluer it appears, due to Rayleigh scattering. Which is also why the sky appears blue when lit up by the sun.
However, I have never seen a distant white cloud be any less white than close ones. When it comes to darker clouds, which are grayish up close, they DO get bluer in the distance. But white ones always seem white no matter the distance, even when a mountain is right below it and very blue. Why does this happen? | Rayleigh scattering redirects shorter wavelength light (primarily blue) coming from a source into another direction. This results in two effects:
1- If you look at something relatively bright (say the sun) it appears red because some of the blue light that would have reached your eye is scattered away into other directions.
2- If you look at something relatively dark (say open sky) it appears blue because the air molecules in between you and the dark object "glow" blue (as a result of light scattered from brighter objects in other directions) adding more blue to what you see.
Both of these processes are always simultaneously competing. In bright objects the light scattered away is the dominant effect making them appear red. In dark objects more light is scattered into your line of site than out of it so they appear more blue. In your example dark clouds and the mountains are dark enough that they become more blue while the white clouds are in the region were the effects of the two processes are roughly equal so the color does not change significantly.
EDIT: note that Rayleigh scattering redirects all wavelengths of light not just blue, it is just a very week effect in the longer wavelengths (the strength of scattering is proportional to 1/wavelength^4 ) | 14 | 32 |
Why did most plants end up being hermaphrodites while most animals end up with two distinct sexes? | The vast majority of plants have both male and female sexual organs, and when two or more plants fertilise each other, all normally produce seeds or spores.
However in most animals the population is divided into males and females, of which only the females bear offspring. | Plants do not have the same kind of opportunity that animals have to find, pursue, and mate with another member of their species, since they are either rooted in one location, or in the case of aquatic plants, just go wherever the water takes them. Plants cannot really compete for mates or evolve into a more sexually attractive form. They just cast their spores to the wind. So sexuality has a much more active role in the animal world. | 12 | 19 |
Where does the energy difference between absorbed and emitted photons go to? | My teacher told me when a photon is absorbed and emitted again, it has a lower frequency. So it loses energy. Where does that energy go to? | Typically, when we talk about photons being absorbed and emitted, we're talking about electrons in an atom doing the absorbing and emitting. An election in an atom is attracted to the positively charged nucleus, which causes it to "orbit" in the closest possible position to the nucleus. (I put orbit in quotes because electrons don't literally orbit like planets, but it's a useful image.)
In order to move an electron away from its nucleus, you need to add energy to it. It's similar to pulling two magnets apart: if you don't touch the magnets, they'll stay connected, but you can pull them apart, which uses the energy in your body and adds potential energy to the magnets (the potential energy turns into kinetic energy when you let go of the magnets and they snap back together).
So when a photon is absorbed by an electron, the electron gains the photon's energy, causing it to jump to an orbit further away from the nucleus. If the photon has enough energy, it can even knock the electron clean off the atom.
Now, due to quantum mechanics, an electron can only orbit at certain distances around an atom, and these specific distances correspond to certain amounts of energy. After a little bit of time, an electron that has been bumped up to a higher energy orbit will re-emit a photon, losing some energy and jumping back down to a lower-energy orbital. Most of the time, it will re-emit a photon of the same energy that it absorbed and jump back to the same energy level it was at before. But if the photon was energetic enough to knock the electron up by a few energy levels, it is possible for the electron to only drop partway, and release a photon with less energy. That photon will have the energy equal to the difference of the two orbitals that the electron moved between. A short time later, the electron will drop again, emitting *another* photon with less energy than the original, again equal to the difference in energy between the electron's old orbital and it's new one. This process can happen as many times as there are empty orbitals between the electron's current orbital and the one it wants to get back to (which is the lowest-energy orbital that is currently unoccupied), but usually an electron just drops the whole way in one step, and less frequently drops in smaller steps.
In any event, when an electron drops some number of steps at a time back to its minimum energy orbital, the energy of all the photons it emitted will add up to equal the energy of the original photon that it absorbed! | 54 | 52 |
CMV:I don't think it matters whether the Grand Jury thinks Darren Wilson is guilty, he should have been indicted anyway. | In the case at hand, there is doubt about the guilt of Darren Wilson. I am not saying whether or not he did anything illegal because I do not know, but the job of the Grand Jury is also not to determine guilt, it is to determine whether the case deserves a trial.
http://www.vox.com/xpress/2014/11/26/7295595/eyewitnesses-ferguson-grand-jury
As per that article, it is unclear what happened. This is enough confusion to require a trial, and it doesn't matter from the perspective of the Grand Jury what the outcome would be, it should still be requiring a trial.
To be clear, it is not a question of guilt that the Grand Jury should be answering, it is a questions of whether they are 100% sure that what has happened breached no laws.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | The grand jury's role is to decide if the evidence present is substantial enough to go to trial. They decided that whatever evidence there was was not enough to justify holding a trial. We don't know exactly what evidence was deemed admissible by the courts to be heard by the grand jury. The media has been showing us a conflated view of what evidence there is and what it shows. Some sources are clearly biased in favor of Brown while others are clearly biased in favor of Wilson. What the grand jury was presented was a cold listing of the facts that would be admissible in court. Keep in mind that newspapers have no requirement to use relevant or verified facts to the extent that courtrooms do. | 78 | 69 |
CMV: Evidence-Based Policy is Overrated | I participated and was a volunteer for the Science March in Amsterdam. So don't get me wrong, I think that evidence-based policy is important. However, I have come across the idea that all policy must wait for evidence, which, as a designer, I think is misleading.
Recently, I attended a research conference for education. This conference is organized by an organization that educators can tap to provide data for lesson plans. That's great, it really is. The conference started with a so-called pitch round, where different researchers pitched data and it's importance. That is where my red flags began raising, though.
The researchers were presenting data of the past two years that they had collected. For example, data suggested that children like using paper over digital tools for certain tasks. Which is fair enough advice. However, the data was being presented as conclusive. Because of it being a pitch, people had to be hyped up by the data, so the data was being presented in such a way that it seemed like this was simply how brains were wired.
The thing is; many data points aren't useful in a single snap-shot. You have to collect data over many years to find a trend and even then, you cannot infer from the data what the causal link is most of the time, because of hidden data that you didn't know was relevant until after you've seen the other data.
So, all I could think during the conference was 'all of this may change in six years when children have grown up with digital tools; teachers are being set up for failure here'.
Which is the crux of my argument. While a lot of evidence based policy, like climate change, is based on evidence that has already been collected, you cannot demand that all policy be backed with evidence. That means that you'll always lag behind the reality.
Take the education for example. Let's say that it took 2 years to collect the data that learning to read is easier with paper tools than digital tools, but expanding vocabulary is easier with digital tools than paper tools. If you base policy off of this data, even corroborated with studies from the same period, you'll be lagging behind, since the educators first need to change their lesson plans and learn to educate in a new way. For the sake of extrapolating this argument to other areas, let's make the unrealistic estimate that it takes a year for the new policies to become nation-wide.
Already, we'd be lagging behind 1 year. By the time that we get the results in, it might be another 2 years. So, already, we are far past the time period it took to collect the data in the first place, so another study may have come out that contradicts the first one, not because the first one was wrong, but because the second study described the applicability of the tools with new technology and a new level of digital literacy in children.
It becomes a rat race of running after the facts. Instead, if you want better results, it can be better to try and find ways to make existing methods more efficient. To look at how school buildings are designed and to reduce the amount of time is spent wandering the halls between classes. Policies can be designed with economic theory in mind for how much incentives children have to pay attention in class if their digital devices can provide them with more entertainment than the teacher can with no apparent cost from getting caught.
Those changes in policy don't require evidence, so much as they do planning and a good kind of sense. You can argue that they are, indirectly, based on evidence, but that is a different category of motivating policy change than we see in for example the climate change debate or occupational risk policies. And even the latter is still mostly based on anticipation and prevention rather than measurement.
Maybe I'm not seeing the big picture, though. Maybe evidence-based policy has merits over other kinds of policy. I think that evidence-based policy is predominantly good for things we have data for over a large scale, not local policy.
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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!* | You're misunderstanding proper application of evidence-based policy.
Evidence based policies are aligned with the whole body of evidence. Progress in science is typically very gradual (outside of paradigm shifts). Singular studies in science aren't very valuable, and no one who understands how science works would base policy off of a single study. Evidence based policies do change, as the body of evidence changes, but as already mentioned, that body of evidence changes slowly, and new ideas/findings take time to become better and better established until they can be considered well-established. So a proper implementation of evidence-based policy for something like education simply won't immediately jump on some new study and ASAP, change educational methods in accordance. It'll slowly incorporate findings that are well-established by the evidence. And like you mention, the evidence regarding certain things can change due to generational/technological factors. The evidence will incorporate that as well. It's insane not to adopt methods based on the evidence; if you don't do this, you're simply not changing your methods for the better, or at the *very least* not changing them for the better as much as could have occurred. And it's equally insane to adopt methods before the evidence regarding them is well-established, because you might be wasting your efforts.
> To look at how school buildings are designed and to reduce the amount of time is spent wandering the halls between classes.
This is an evidence based approach (as is your other example). You build a model which incorporates student behavior with respect to transit within a building, and optimize to minimize walk time. (As a bit of a detour, most major companies that have hourly workers that punch in/punch out via some means, do considerable analysis and optimization regarding start of shift and end of shift walk times, and also do analysis/optimization of during-work walk times... the evidence-based consensus on this is that it's quite valuable with respect to maximizing production per time. Schools not doing this already is an example of *not* basing policy on well-established evidence. And it's not like this just became well-established recently, it's been well-established for over 100 years now.)
Although you say that this is only indirectly based on evidence, you are incorrect. Climate science uses similar modeling approaches (e.g. regarding climate change). They build models based on all the known facts, and these models can be used in a predictive capacity. Furthermore, those models *can* be used with respect to optimization problems (e.g. determining what some of the most efficient ways to cut warming per dollar are). This is *a lot* more complicated than such a simple modeling approach of walk time minimization, because we're literally talking about thousands of variables that have very complex interactions with each other, but it's still exactly the same principle of what we're talking about above. And we're still learning and gathering more data, which can be incorporated into our understanding (and our models).
Climate scientists are still gathering additional data, and incorporating that data into their models, regarding say, climate change. Climate change is already extremely well established, and it's clear that no new data is going to completely overturn our understanding of it, but there's still a lot we don't know, and gathering more data and incorporating that into our understanding (and subsequently allowing that to fine-tune our policies) is quite valuable. There's literally no reason this exact same methodological approach can't be used to inform and develop evidence-based policies for something like education. | 12 | 18 |
What purpose do the ridges & depressions common in food containers serve? | They are present on the lids and sides, make manufacturing more difficult, and use more plastic rather than a flatter surface.
Initial thoughts are maybe to disperse heat better or maybe lower surface tension (making it less susceptible to cracking)
Edit: Thank you to everyone for your replies!
For future readers the answer is essentially one word: corrugation. Corrugation adds strength and durability while using significantly less plastic than would be necessary for a flat border with similar durability & strength. Another benefit is grip (think bottom of a bottle wouldn’t stay put as easy if it had a flat bottom) and some ridges are potentially remnants of the manufacturing process (unconfirmed). | They provide structural support. If everything was flat plastic it would bend so much it would either crack, or be so flimsy as to act as a stiff plastic bag. It actually saves plastic because the container would have to be a lot thicker otherwise.
Look at the difference between bottles with flat sides vs something like a Gatorade bottle. | 31 | 17 |
ELI5: When you load a new website how can we trust the website is legitmate? Is the ssl certificate downloaded in browser or perhaps we verify signed certficate with the CA immediately? | the SSL certificate is sent by the webserver to you, which is valid only for each connection you make to the webserver (as it is part of the encryption).
You (or your browser) check the legitimacy of that certificate by checking that some trusting agent has signed that certificate.
An attacker could have sent his own (false) SSL certificate, but then it won't be signed by some trusting agent. Unless the attacker has also compromised the trusting agent, in which case your browser (and everyone else in the world) should ignore the signatures from that agency. | 11 | 17 |
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What is the process for decontaminating sites where nuclear waste is present? | Just wondering the main stages after a nuclear event both long term and after and if there is regulations for it
Also any links to interesting videos on the subject | 1. Measure, measure, measure:. Which isotopes in what chemical form. Whats the environmental matrix (sandy soil, clay, etc.). What horizontal and vertical distribution? What's the water table and surface water conditions, etc.
2. Stabilize:. Stop it from moving due to wind, rain, ground water flow, etc. Maybe a quickly deployed ground cover like hay and grass seed. Maybe subsurface pumps to keep it from going down into the water table, etc.
3. Remediate: depends on the details, but could for instance be scrape off the top few inches of contaminated soil and pack into drums. Sometimes the best option is just get it covered in grass and leave it. Drums will be analyzed for content and shipped to a waste storage site, often a carefully prepared area with no chance of ground water contamination. | 22 | 63 |
What are the macro economic drawbacks for canceling student debt? | From an unbiased stance, are there any negative economic impact for the American nation on a macro scale for just canceling the trillion dollars in student debt? | 1. Increased national debt and the consequences that come along with that
2. Increased inequality. Student loans are disproportionately held by Americans with well above average lifetime incomes
3. If this is a recurrent event - moral hazard (this is microecon). Even not explicitly stated, merely the expectation that debt might be forgiven in the future could distort decision making. | 243 | 139 |
ELI5: What causes that feeling of "emptiness" when someone experiences an episode of depression or sadness? | It is not fully understood by science but much research points towards some form of serotonin deficiency, in either its production or turnover in our bodies. Serotonin is a neurotransmitter that we synthesise from the tryptophan we eat in our food and helps us regulate mood. Whilst poor diet can clearly contribute it is also clear that certain experienced events can also disturb our brain chemistry. Generally speaking that emptiness will also coincide with a lower level of serotonin or an ineffectiveness of the serotonin receptors in our brain to process it. | 4,592 | 12,217 |
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What makes a work of art 'good' by contemporary philosophy of art standards? | I’m an undergraduate taking an Aesthetics course. Gordon Graham provides three normative theories for evaluating art: expressivism, cognitivism, and hedonism. Graham is a cognitivist, meaning he thinks what the extent to which art helps us understand truths about the world and our place in it is the metric by which we (should) judge the value of art. | 35 | 67 |
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Why can't animals with gills breathe air? | Fish gills are very delicate, and have a very large surface area (which makes them work so well). It is completely dependent on being immersed in water to support their weight. Out of the water, the delicate gills will collapse like wet tissue paper, and very little surface area is left exposed, so gases can not be properly exchanged. Therefore, most fish can't survive out of the water for a long time, because oxygen deficiency will catch up with them and they asphyxiate.
If we could find a way to keep the gills supported and moist without being immersed, a fish could survive for a lot longer, but this it isn't physically possible, even in a humid air-filled chamber at zero gravity, considering that the gills would just stick to one another. Water must completely fill the gill chamber to keep everything else in working order. | 35 | 33 |
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does the amount of tension a wire is under affect its ability to conduct electricity? | If so is it only to a minute extent? | Yes, mechanical strain affects the resistance of a conductor three ways.
The resistance of a wire is (rho)L/A, where rho is the conductivity of the metal, L is length and A is cross-sectional area. If you stretch the wire, L goes up, A goes down, and rho goes up because the molecular bonds are being strained. The effect of rho changing is small in metals, but much larger in semiconductors.
All three of these effects, taken together, are why we can measure stress and strain on objects with strain gages -- a subject well worth googling. | 22 | 31 |
ELI5: Why is it that when someone suffers from amnesia, they forget specific things or completely who they are but not how to act as a human and complete basic tasks like eating and talking? | Different memories are stored in differing parts of the brain, with differing degrees of permanence.
If the amnesia affects only one part of the brain, then memories stored elsewhere are unaffected. In fact, when trauma happens to the language centers of the brain, a person can "forget" how to speak and understand speech properly, yet be fully cognizant of how to cook meals or what house they live in.
For obvious reasons, the brain stores its most essential memories - like how to eat, what is edible, what causes pain - in the most protected sections of the brain. Both short-term memory (what card did you just pick?) and medium-term memory (What year is it?) are more volatile. | 21 | 17 |
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Why does CO2 only reflect heat back at the earth? | Shouldn't CO2 also reflect heat back at the sun, as well as back at the planet? Or is there something else? | The energy coming from the sun comes at frequencies that can pass through the atmosphere (visible light, UV, etc.). The earth re-emits the energy, but at a lower frequency (infrared). The lower frequency radiation is absorbed by the atmosphere. | 44 | 38 |
At what point in your learning can you start looking for internships? | I am currently a college student majoring in computer science and I have so far taken a python and a basic CS class. This semester, I'll be working with Java, PL/SQL, assembly language and might also take some web development classes. Students my age seem to be getting internships already but I do not know if I have enough knowledge yet to do an internship. When do you think is a good point to actively start looking for internships or what skills should I learn before I start? | You can do an internship at any time. The purpose of an internship is to learn, so if you can find one then go for it. It's never too early to start looking, and the experience is way more valuable than any of your classes. | 13 | 18 |
ELI5: How come when I am laying in bed at night and left with my thoughts I want to start working proactively in my life, but when I wake up I couldn't care less? | It's the difference between living "idealistically," which can stay a dream, and actually doing the hard work it takes to make those dreams come true. When you lay in bed thinking, tomorrow seems like forever away. When it's morning, the hardships of reality kick in. | 19 | 33 |
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How were diffraction patterns for crystallography resolved before computers? | Was it done using pencil and paper calculations that translated into structures or did the patterns more directly correspond to certain structures?
Edit: clarified in post body | Only the simplest of crystals could be understood definitively, because you can predict the diffraction patterns for a given crystal type. Even the DNA diffraction pattern in the classic Watson and Crick paper (done, of course, by Rosalind Franklin) only gave a general (double) helical pattern, not the exact crystal structure. | 10 | 23 |
ELI5: Do I get more pizza with one 18" or two 9" pizzas? Is there a formula I can use to work out the relationship between the areas of different sized circles? | Pull out two coins and set them side by side.
See how the two together are wider then they are tall?
Imagine a circle around the whole thing that touches the left and right sides.
See how much higher then the coins that circle goes?
The same thing works for any circle, including pizza, see all that missing space between the actual coins and the imaginary circle? that's all the pizza you can't have if you get the two small ones! | 212 | 52 |
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CMV: Knowledge about the size and scope of the universe does not make me feel small and insignificant nor do i think it should. | I have heard people talk about how small and insignificant we or a person is compared to the universe, heck i even think Sagan said something like that. But i see no reason to feel that way. Yes the galaxy is big (an understatement) but really to a person that really dosen't matter. To quote a story "we are all the heroes of our own adventures."
Our personal universe is the area and people around us, they are what matters in our day to day lives. If anything i would say that the size of the galaxy is so large and unimaginable as to be meaningless in our lives.
What does the fact that we are just one planet out of trilions change in our day to day relations. And yeah we might not be special or even the only life but so what its our world that matters.
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> *Hello, users of CMV! This is a footnote from your moderators. We'd just like to remind you of a couple of things. Firstly, please remember to* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! If you are thinking about submitting a CMV yourself, please have a look through our* ***[popular topics wiki](http://www.reddit.com/r/changemyview/wiki/populartopics)*** *first. Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | The point isn't to make you feel insignificant, it is to provide a beneficial perspective in life.
We often get so worked up in the details of our daily routines and personal squabbles that we never stand back and realize the bigger picture.
How petty is a fight over a small piece of land in a universe of potentially infinite size? What importance is there to the color of one's skin when there is potentially a universe teeming with life of infinite variations?
That is what the knowledge is supposed to inspire. Not irrelevance, but limitless potential. | 25 | 33 |
Research position at rural vs. urban R1 | I have a friend who just finished their postdoc at a top tier school and now they're searching for a research position at an R1. USA, neuroscience. Obviously the competition is extremely high.
Maybe rural vs urban isn't the right idea, but I'm wondering if there's a difference in competition at schools in big research areas vs. schools in isolated research areas. Like UCLA vs. University of Maine. I assume that UMaine has much less competition if people are turned off by the lack of local opportunities for collaboration, small rural towns, always traveling far for conferences, limited opportunities for trailing spouses, etc. And UCLA would have more competition for the opposite reasons. On the other hand, maybe the high amount of competition completely negates everything else and there are still more people willing to move to isolated areas than there are available positions.
Either way, I haven't been able to find much info at all. Anyone have some insight? | Tenure-track jobs are rare enough that there are likely hundreds of applicants for each position. We all realize we have very little control over where we live, and will apply for any job we would reasonably take - while "reasonably take" will vary from person to person, the competition is enough that there really isn't an "easier" tenure track market. You're right that jobs on the coasts or other desirable locations are likely to get even MORE applicants, but that doesn't mean that less-desirable places somehow suffer or that the competition there is easier. | 55 | 31 |
ELI5: Why does white light contain all colors of the spectrum, but when you combine every color you get black? | Pigment is subtractive, in that when you add pigment together, you subtract the wavelengths of light that can be reflected. At some point, you add enough pigment together that you have subtracted every wavelength of light as it hits the combination of pigment, so what you see is black (obviously you aren't absorbing 100% of visible light with the tech we have right now, but enough that there is no color to be identified so you end up with what we call black).
Light is additive in that as you add visible light waves together they approach what we call white - the presence of all visible light waves. | 85 | 27 |
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ELI5: Why can’t gravity be blocked or dampened? | If something is inbetween two objects how do the particles know there is something bigger behind the object it needs to attract to? | The other explanations here are not really getting at the heart of your question (which isn't any different for gravity - other forces do the same thing).
Your error is in going "this is a solid object and nothing can go through it". But what you think of as "solid objects" are not completely impenetrable. As an everyday example, light has absolutely no trouble going through glass.
[EDITED to clarify: this part is here to explain to OP how their idea of 'solid' is inaccurate. It's not directly about how forces can go through things] ~~'Solid' objects don't fill up all the space in the region they occupy (in fact, they're not even *close* to filling up all the available space). They seem solid on human scales because electrons repel one another, so once two atoms get even somewhat close, they're pushed apart by the repulsion of the electrons in each atom.~~
On an even more fundamental level, fields (like the electromagnetic field or, if you set aside some of the weirder aspects of relativity for a sec, the gravitational field) aren't different things from the physical objects around you. Objects are "made of" these fields, in the same way that a wave in the ocean is made of water. What we think of as a particle is just a place where these fields take on different values from other parts of the field, in the same way that a wave is just a place where the water is a little bit higher. And so your question becomes, roughly, "how can water travel through a wave?".
If this seems strange, well, it is. There's a reason it took fifty years and some very surprising experiments for the most brilliant minds in physics to figure it out. | 4,169 | 1,187 |
CMV: British agriculture should be allowed to decline and land stewardship should be transferred to the National Trust, Forestry Commission, and environmental charities | Posting here because it's pretty difficut to find facts which support or refute this view.
It seems to me like we are being asked to artificially support a dying industry that has no real value for modern Britain. Farming is becoming increasingly marginal, especially livestock farming. Other countries, mostly European ones, are perfectly capable of producing all the staple foods we consume, and we import more exotic luxuries anyway. Meanwhile, because farming is so marginal, many farmers don't have the time, money, or energy, to care for the environment they occupy. Modern technology allows farmers to modify the landscape to suit their needs, and they're no longer obliged to treat it well in order for their farms to survive. Farmers use herbicides, pesticides, and fertilisers, that poison the water table and reduce biodiversity. They leave litter in their fields and in the land beyond their fields, like fertilizer bags, feed bags, old salt lick buckets, and piles and piles of old metal machinery. They erode the land by driving through it with tractors, jeeps, and quad bikes, by diverting water ways, and by not practicing crop rotation. Their hunting activities contribute to loss of biodiversity, especially when they maintain grouse runs or carefully managed, monoculture plantation forests for pheasant shoots. When I've challenged farmers about these issues (admittedly I've only been able to speak to two or three children of farmers who are my friends/acquaintances) they say that they simply don't have time to be worrying about these things because it's hard enough to make a living as it is.
What exactly is the benefit of maintaining such an industry? Why is it subsidised? Why are we encouraged to buy locally? Why protest against the dropping price of milk? It seems to me to be much preferable to allow farming to die out due to market forces and transfer care of the land to bodies who are more capable and have a greater incentive to do so.
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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!* | It's very important for a country (and especially an island country) to maintain an ability to feed itself via farming in a case of unforeseen emergencies which can make trade for food difficult or impossible.
Maintaining farming infrastructure is essentially an insurance policy against starvation should things go wrong. | 25 | 53 |
Why is elevating your heart rate through exercise good for your heart but elevating you heart rate with caffeine bad for it? | Elevating your heart rate through exercise causes your vascular system to dilate, allowing for greater bloodflow. When the veins are wide open, the heart does not need to work as hard to pump more blood. However, caffeine is a vascular constrictor, causing your heart to work harder to pump the same amount of blood. Coupled with an elevated heart rate, your heart is now trying harder to force blood through constricted passages, which puts undue strain on your heart and your vascular system. | 1,743 | 1,695 |
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CMV: Exposure to Misinformation and Invalid Arguments is Crucial in the Exercise of Critical Thought | John Stuart Mill said it best when he argued 160 years ago, in his classic *On Liberty*, that it is impossible to truly know if 'x' is false if we refuse to hear any arguments or evidence purported to be in favor of 'x'. If, for example, a given society were to decide that holocaust deniers and anti-vax people should be fully silenced to the point that I never heard their reasoning, then I would not be in a position to know whether in fact their arguments were invalid. And since being able to compare arguments in order to determine which ones are valid or invalid is a part of critical thought, my opportunity to exercise such critical thought would be greatly diminished.
Potential Objections:
1. On several issues common sense or intuition can be used to arrive at the truth without the help of critical reasoning. Response: common sense and intuition are not infallible and thus need to be verified through the testing of evidence and critical thought. Many people have erroneously believed, for example, that it is self-evident that the earth is flat or that the sensation of color pertains to the objective world.
2. We've already heard enough to know that the holocaust deniers and anti-vax people are wrong. Response: that in itself proves the point that hearing such arguments is useful in determining what is true or false.
3. It is sufficient if others, as with previous generations or experts, hear those invalid arguments on our behalf in order to determine if they are valid or incorrect. Response: previous generations and experts can certainly do that, but if we ourselves simply trust them then we are merely conforming to their views rather than exercising critical thought or exhibiting genuine knowledge (on the assumption that having the correct view on the basis of conformity is not the same as knowledge).
4. It is for our own protection that we should not be exposed to misinformation. Response: perhaps so, but that does not relate to my view apropos of critical thought. It simply states that the harm outweighs the need for free speech and critical reasoning.
If I've missed something I'll add an edit. *But as a last point I will add that if my view is changed, then in a certain, perhaps ironic sense it would actually be proven, since it would show how a misinformed view grows into knowledge not through its censorship but rather through hearing a variety of ideas in the exercise of critical reasoning.* In which case I would be happy to change my view!! :)
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EDIT: I forgot to clarify that while I believe that exposure to misinformation is crucial to the exercise of critical thought, it is not a sufficient condition of it. For example, if I am a deeply ignorant, uneducated person who is psychologically susceptible to propaganda, then being exposed to bad ideas won't by itself suddenly make me a critical thinker! But, nonetheless, if I am to develop into one then at some point I must be able to analyze bad information. | Misinformation that is presented critically is helpful in exercising critical thought. There is plenty of misinformation out there that can be analyzed and dissected, and there always will be. Misinformation that is spread widely with no context to masses of people with little to no critical thinking ability on the other hand is dangerous to critical thought. | 48 | 135 |
Can you substantially heat a liquid by shaking it to produce friction? | Yes, example being high end blenders. A vitamix blender left on maximum for several minutes can heat soup (to the point where you need to let it sit before drinking) through friction. The motor in the base of the blender is connected to the blade via a plastic gear so there is little chance of any heat transfer occurring that way. | 10 | 17 |
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ELI5: Explain time signatures in music | I actually understand the "over" number. But in a waltz,
3/4
I don't understand how one derives the 4. | The bottom number indicates the type of notes filling each measure, and the top number represents the type of note the tempo is broken up into. So 3/4 would mean 3 quarter notes per measure, and the conductor would wave his baton 3 times per measure. And 6/8 would represent 6 eighth notes per measure. Also, there is common time, denoted as "C", which represents 4/4. Correct me if im wrong. Hope this helps. | 10 | 18 |
In a plant seed, has the metabolism completely stopped until germination or is there still very very very slow "life" happening? In other words, is it "paused", or is it consuming energy very slowly? | Seeds have inhibitors in place to prevent wasting Large amounts of energy and germinating In conditions that do not have adequate: water, oxygen, temperatures, or soil. Some seeds do use small amounts of energy while dormant to fuel cellular respiration.
So, to answer your question, seeds that haven’t germinated yet use small amounts of energy for basic processes to stay alive and wait for good germinating conditions. | 12 | 21 |
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ELI5: Why do some helicopters have two rotor blades and others have four ? And what exactly are the benefits of each type? | I've always wondered that. | How much wing you need to lift how much weight with how much engine. Each blade is extra weight and extra torque you need from your engine. The upside is that each extra blade gives you more area to generate lift and speed. So it's a balance between the two. | 51 | 84 |
CMV: Mental illness diagnosis is a very imperfect science that can be harmful at times | When you break your arm, the doctor can look at an x-ray and determine you broke your arm.
As far as I know, when it comes to mental illness diagnosis, a psychologist will talk to a person about their problems and feelings, ask them questions and make a diagnosis.
Before I go any further into this, I want to say that I think mental illness is very much a real and serious thing. I'm not saying that it's made up or even over-exaggerated.
That being said, I have heard people say that after going through tough times they were diagnosed with bipolar disorder, or clinical depression, or anxiety, etc.
And I do wonder, if all we have to go on is the way a person can articulate their thoughts and feelings to a psychologist (probably one they barely know at that) isn't there a ton of room for misdiagnosis? Aside from the fact that people can lie/exaggerate sometimes, even people who feel they are being 100% truthful are unlikely to be able to fully accurately represent what they're going though. It's common to hear people say they can never describe what something like love or happiness feels like, so wouldn't the same apply to despair and depression? And wouldn't it be hard for even a trained professional to see through the bullshit so to speak when they're probably only spending a small amount of time with the person?
Wouldn't it be incredibly harmful for a person who is going through a difficult time in their life to be told say, that they have an anxiety disorder if that person didn't actually have it? Especially if that person is then given medication. Even if not given medication, a placebo effect could still derail that person's life if they start overthinking things all the time because they think they have anxiety, or they use their misdiagnosis to justify certain irrational behaviors.
You hear people all the time say they "play the game" with their doctor so they can be prescribed marijuana, adderall, xanax, etc. If we know that works so often, who's to say that an innocent person can't also be given a drug they don't need just like someone seeking it out can get it when they don't need it?
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> *This is a footnote from the CMV moderators. We'd like to remind you of a couple of things. Firstly, please* ***[read through our rules](http://www.reddit.com/r/changemyview/wiki/rules)***. *If you see a comment that has broken one, it is more effective to report it than downvote it. Speaking of which,* ***[downvotes don't change views](http://www.reddit.com/r/changemyview/wiki/guidelines#wiki_upvoting.2Fdownvoting)****! Any questions or concerns? Feel free to* ***[message us](http://www.reddit.com/message/compose?to=/r/changemyview)***. *Happy CMVing!* | I don't think anyone is going to disagree with your premise, not even psychiatrists or psychologists - everyone agrees that there are occasionally misdiagnoses - so what exactly is your proposal based on this premise: do you think there should be no attempt at ever diagnosing mental illness and offering treatment? Or is it that there should be no treatment against a person's will? Or what? | 14 | 34 |
Is it better to learn c++ before learning python? | I just started learning programming | Depends on what you want to do.
C++ is a lot more complex than python and require understanding many more concepts to actually be able to do anything.
This makes it harder to learn as a first language, but if you are motivated and like to learn how things work deep down, or aim to work with C++, it's a good first language. | 24 | 25 |
CMV: Colonisation overall was a net positive for the world. | Reasons
1. It created the modern nation state which paved the way for stable borders and is the reason war started to decline. Democracy also started to become commonplace since permanent populations and institutions like school started to become mainstay.
2. *The UK* stabilised warring tribes into democracies.
3. Europe imported the rule of law, *especially the UK* for the first time for just about the rest of the world, people were ruled by laws and not by the strongest tribe or leader. It was also the first time that the law was no longer arbitrary based on which group was in better with the ruling class.
4. They imported the industrial revolution which greatly increased the life expectancy and standard of living.
5. Modern medicine and science we have Europe to thank for *Mostly Germany* which they gave to the rest of the world due to the fact that the whole world now had functioning nations and economies.
6. The continents and islands went from being separate worlds to being one connected world.
In closing, if Europe had never colonised the world they would be at the space age and the rest of us would be still tribal, warring, and likely very uncivilised. So we should be grateful for them deciding the rest of the world was worth exploring. | There are two types of colonization, both of which caused problems but one more so than the other.
1. Settlement colonization - Examples here include the United States, New Zealand, and Australia. The purpose of this type of colonization was to take people from your original country and start building a home for them in the new land. This is the type that is the cause of virtually every positive that you have listed - though your positives aren't quite accurate. Settlement colonization is the earliest known form of colonization, it was practiced heavily by the Ancient Greeks who would send their pioneers out to Sicily, Turkey, Italy and build new cities. When practiced in the modern era, it has invariably 100% of the time led to genocide of the existing population in the place you decide is your new home. The extent of the genocide differs - the Maori in New Zealand weren't slaughtered as thoroughly as the Native Americans in the US, but even a little genocide is enormously unacceptable.
2. Extraction colonization. This is the big one that fucked up more of the world than anything else. This was what most of the colonization in Africa was. The Europeans set up shop, threaten to kill anyone who resists, enslaves the population and has them dig up the rich natural resources that are abundant in Africa and then they transfer that material wealth back to Europe. The only countries in Africa that avoided this were Ethiopia and South Africa - Ethiopia because they got lucky and it was the Italians who tried to take over instead of the French or the British, so they kicked their asses. South Africa was a settlement colony and, like all settlement colonies, underwent a genocide because of it. So how are the Africans supposed to keep up with the rest of the world's economies who keep advancing post-Industrial Revolution when all of their labor is just collected and shipped off to Europe where the Europeans can become rich off of it and the Africans can't? The Africans are also unable to participate in the Industrial Revolution, not because they lack the resources or intelligence, but because their countries have been taken over and they work in a command economy set up by foreigners.
The extraction colonies have fallen for the most part, a big part of that is that WWII was too costly and the British and the French couldn't afford to defend their colonial possession anymore, and here's where - after stealing all wealth for hundreds of years - they really fucked things up. European nations were allowed to develop their own borders as a result of their history. After countless wars, massacres, and genocides in Europe, most people had a country that worked for them and the borders were rarely in dispute. Instead of letting the borders of their colonies develop naturally, the colonizers just split lands and peoples willy nilly.
In 1947 the British thought it'd be a cool idea to split the nation of India between Hindu and Muslim. Lord Mountbatten, the man behind the partition, didn't know shit about how to do that so he just drew two lines on a map and was done with it. The result was 200K-2M deaths and 14M people displaced.
Other genocides that occurred because the colonizers decided to put persecuted groups in new countries that were led by their persecutors - Rwandan Genocide, Sudanese Genocide, two Ugandan genocides.
Other great moves - promising the people of Palestine that they'd get to keep their land after they were conquered. Then promising the survivors of a German-led genocide that they'd get their ancestral homeland, which had just been given to another group. Now Israel and Palestine don't exactly see eye to eye, and they exist like this as enemies because of the artificial development of them as a nation that was caused by colonization.
TL;DR - Africa had all their wealth taken for hundreds of years and then the colonizers just left and gave them shitty borders that they didn't want, putting opposing groups together and splitting their power for no real reason other than laziness and being dumb. Seriously, look at a map of Africa, all those straight lines on their borders are European colonizers just getting bored when figuring out how to split them. | 46 | 15 |
Are there any good books on how the scientific revolution of the 16th century brought about that "science" and "philosophy" started to mean different things? | I can't think of a book that covers this topic explicitly (/u/wokeupabug might know one). It's a hard topic, in part because the change is not at all abrupt. "Scientia" has a distinct meaning before the 17th century (that's the century you want, by the way), but isn't really applied to science as we now understand it until Galileo's *Two New Sciences* and even after that not consistently. And the term "scientist" doesn't come into being until the mid-19th century, when it was coined by an anonymous commentator on Mary Sommerville and popularized by William Whewell.
What you see in the meantime is a slow disassociation of what we now think of as philosophical concerns from those of physics and biology. But this change didn't happen overnight. Critics raised philosophical objections to Galileo's work (and lost). They raised philosophical objections to Newton's work (and lost). They raised philosophical objections to Darwin's work (and lost). And they raised philosophical objections to Einstein's work (and lost). (You might note a pattern here.) So it's not a simple story by any means. | 12 | 27 |
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ELI5 - whatever happened to acid rain? | Acid rain is primarily caused by specific kinds of air pollutants. Legislation in North America and Europe successfully limited the emission of these pollutants--for example, through the establishment of a "cap and trade" system that limits the total pollution and requires companies to pay more to buy the a greater share of that cap. That's why it's not nearly as serious of a problem anymore in the West and you don't hear about it: the solutions are working.
In many industrializing countries, however, like China, acid rain is still a serious problem. | 201 | 224 |
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ELI5: why is democracy generally praised while populism is generally denounced? | Both appeal to the desires of the majority, don't they? | Democracy is usually understood to appeal to the majority while respecting basic rights and freedoms for the minority.
Populism is more of an us-against-them appeal to the masses against the elites. It's much more one-sided and exclusive. | 12 | 18 |
Are President Biden's policies responsible for America's high inflation? | Ok so it? President Biden is getting blamed by many. I thought it is another effect of coronavirus. I don't blame his policies. I also thought that if Trump were president, he would be facing similar inflation rates. | Simple version: it’s due to Fed Monetary policy and mostly due to global supply chain issues caused by the Pandemic.
Presidents will always be blamed/praised for ongoing financial climates despite having much smaller impact than most believe. | 19 | 26 |
How can the Universe be infinite if it is expanding? | How can the Universe be infinite if it is expanding? Aren't those two ideas mutually exclusive?
What about the widely accepted idea that the Universe was at one point a singularity, so if that is true then how can the Universe be in any way infinite? | The expansion of the Universe isn't talking about its boundaries expanding - we don't have any way of knowing what the boundaries are doing, or whether they even exist (i.e., whether the Universe is infinite), because the speed of light limit prevents us from seeing past a certain distance.
What the expansion of the Universe means is that, if you take any two points (separated by a large enough distance), they'll be moving away from each other. It's a statement that isn't concerned *at all* with how things look on a global scale, just how things behave within a given region. | 34 | 52 |
How does toxicity evolve in animals? | Ive asked this question somewhere else before but only got lackluster responses with the catch all answers 'evolution the end', figured experts might have better answers.
The question is this, how does being toxic to eat evolve in species? Say you are a frog and thanks to a random mutation your flesh is now toxic to eat (even though this would likely be more incremental over genetations?) It seems to not be terribly beneficial to have this trait if it only does something once you've been eaten. I understand how its helpful once the trait is established and predators know your not good eating, but all traits have to start somewhere and I'm curious as to how something only posthumously beneficial gets passed on as beneficial.
Addendum: Why don't we see more animals (i.e. mammals) with this kind of adaptation if its generally helpful not to be eaten. | Toxicity, like all adaptations, evolves through small modifications on an existing template, selected for because it increases fitness.
Your sticking point seems to be in understanding how something not directly beneficial to your own survival can be selected for. That's a great question.
The answer is that you don't need to ensure your own survival for natural selection to act. You need to ensure the survival and propagation of your *genes*.
So, if you sacrifice yourself and kill a predator before it can eat your babies, well done! If the predator - after having had several members die after eating your species and not having a chance to reproduce - evolves to no longer eat species that look like yours...even better! | 12 | 15 |
Are there any examples of organisms that completely contradict the theory of natural selection? | Evolution by natural selection (including artificial selection, humans are also part of the natural world) requires 4 things:
* Offspring are similar to their parent(s)
* Imperfect copying system (in terms of reproduction)
* Variation amongst individuals of a species
* Limited resources
Find a species that species that isn't of this nature and you'll get yourself an organism that doesn't evolve by natural selection.
| 19 | 17 |
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