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[WH40K] On Blessed Holy Terra, a meeting of certain and exclusive dignitaries including an admiral or two will attend private dinner. The guest hotel where I work has been given the responsibility for hosting the event and planning the dinner menu. What do I need to know for success? | You won't have to worry about food as long as it is plentiful and varied, and you won't have to worry about decor as long as it is tasteful.
What you need to worry about is security. Any meeting between dignitaries will be a prime candidate for ambush, heresy, or spying. Expect there to be a LOT of muscle. Arbites will be on constant patrol, and probably stopping to question anybody that comes within a mile radius of the structure. You will probably see military personnel, and it is best not to interact with them. If you are really lucky, there may even be some Space Marines present. You will not want to even look at these guys. Catch a glimpse when you can, but don't you dare stare. If you make it look like you're sizing them up, they will cut you down to size. These guys are not going to take any chances. There will be no warnings, no slaps on the wrist, and no mercy. If you are caught doing something you aren't supposed to be doing, you'll be lucky to simply be thrown in a penal legion.
You will be expected to forget anything that you hear. You shouldn't be listening if you enter the room where these dignitaries are talking, anyways, but if you do happen to hear something you will cleanse it from your mind, or it will be done for you by force.
There is a non-insignificant chance that, despite all of these precautions, something will happen. Maybe a spy will be caught recording, or maybe an assassination attempt will be thwarted, or maybe heretics will try to summon a demon. Regardless of what happens, you will step aside and simply pray that nothing happens to you. If it is spy activity, you will probably be questioned even if you were in a completely different part of the structure. If it was an assassination attempt, you will be questioned to make sure you aren't an accomplice. If it is heresy, you will probably be killed outright because they don't take any chances with that shit.
All you should know is that this is an incredible opportunity for you and your business. Do everything right and you could see more of that kind of business coming in, which will make your life better in general. If you mess even one thing up, though, chances are that you will never again have such an opportunity. | 60 | 59 |
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ELI5: Why does blinking take me almost no effort at all, but winking forces multiple muscles/areas in my face to move oddly that aren't even near my eye (i.e. side of my mouth being raised/lowered)? | The sequence of movements and the muscles involved are the same group of muscles that are active when something's in your eyes. You are not winking but using those muscle groups separately (one side only) to express yourself. It has to do with what nerves are supplying those areas and the nuclei of those nerves. Closure of the eye lid and movement of the muscles are done by the same nerve (Facial nerve). Hence the effort.
It is also a movement that is almost an instinct because you have used them before even as an infant when something gets into your eyes. So kind of like muscle memory but for the wrong task, but it still works at expressing so you keep using it. Practice hard enough, and winking will be effortless. ;) | 28 | 306 |
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Improving the state of /r/AskScience | 4,575 readers as of the time of writing. Wow, that's quite a change from just a few short months ago. Most of the changes are simply awesome. The volume of questions and answers has increased drastically, and we're finally starting to reach some of the goals we set out with: to exist as a reference point for lay people with a scientific inquiry, and as a place for scientists to plumb the minds of other scientists, all in an easy and accessible format.
Yay us!
However, this growth also has its drawbacks:
* The quality of questions is decreasing (I'll explain what I mean by that later).
* The quality of answers is decreasing.
Neither point is at a critical level. The great majority of questions are absolutely excellent, and I've never had a difficult time finding what I would consider to be a "good" answer among the "chaff", even if I don't have the necessary background or expertise to decide whether the answer is right or wrong.
That said, the signal to noise ratio is definitely going down, and I'd like to add some guidelines to the sidebar to improve the situation and keep the quality of content in this subreddit as high as when we first started. Think of it as preventative maintenance, much like an oil change. Please read the following suggestions carefully and help me decide what to put in the side-bar. Feel free to make your own suggestions. I'll add as much to the side-bar as people seem to feel is helpful, and want to limit it only to what is actually/realistically going to improve the subreddit. I'm going to list my suggestions here, but please vote for or against them in the comments - sort by "oldest" if you have trouble finding them.
* When you have a science question, then try: 1) Wikipedia.org 2) reddit's search function 3) /r/AskScience
* If you decide to post a question: Make sure your question is complete, clear, and precise. Avoid acronyms. Avoid using vague terms that might have multiple meanings. Use the text area to explain what prompted the question, your current level of understanding, and what you've already tried (if anything) to arrive an an answer.
* Upvoting guideline: upvote only those comments which directly contribute to answering the question, or related questions spawned by the OP. Only upvote if you're sure the author is correct!
* Downvoting guideline: downvote only those comments which detract from the discussion (distracting memes, off-topic jokes, pseudo-scientific mumbo-jumbo, and anti-science rhetoric).
* When you consider commenting, first ask yourself: "Will my comment help answer the question, clarify it, or consist of a related/tangential question or comment?"
* Consider comments as island statements - *ad hominem* attacks, prejudices/biases for or against the author on the basis of comments outside of the relevant discussion, and unnecessary references to the real-life or internet personalities behind the user name are strongly discouraged.
* Panelists: when commenting on something outside your field, please make a note of it so readers can ignore the tag - this is especially useful for colorblind redditors.
* There are no "stupid questions," only questions that are too vague or drug-addled to make any sense. Feel free to either ask for clarification or downvote.
* Questions that are obvious to you are not necessarily obvious to others - always answer politely and treat everybody with the same dignity and respect that you would show Stephen Hawking.
* The panelists are redditors who are (being) trained in (a) scientific discipline(s).
* Cite your sources.
* Remember that science is a process, and that questions are often (but definitely not always) queries as to the current results of that process, not the process itself. | Suggestion:
* Upvoting guideline: upvote only those comments which directly contribute to answering the question, or related questions spawned by the OP. Only upvote if you're sure the author is correct! | 49 | 129 |
Is the dialectic method truly a science? | When I say dialectic I mean Marxist dialectic. In the socialist literature, I read Marx and Engels both refer to dialectic as a scientific method, Stalin's writings as well.
It is repeated over and over it is a scientific method.
When I think of dialectic I think of having a thesis, and attempting to prove, disprove or expand on it the thesis or creating an antithesis that evolves that original into something new.
According to Marx contradictions cause this for example the contradictions of class society, working-class, and capitalist class with their opposing interests.
Can this be regarded as science though? | Wissenschaft in German is a broad term, and in Hegel in particular (where M&E get their definitions and much of their theory from) it means the systematic and rigorous pursuit of knowledge. This inevitably involves empirics in many spheres, but is not reducible to empirics.
Marxism is a systematic worldview that has significant ontological commitments, epistemological commitments, and so on, which are built up through the dialectical interplay of theory and empirics. These in turn have methodological implications, both for study and for action. In this way, Marxism is a science. | 45 | 43 |
ELI5: Why did humans, and other species, evolve to have both male and female species? Wouldn't it be more efficient if everything could reproduce asexually? | There's probably a simple answer to this, but in reality it would be more efficient for every species to just reproduce asexually. | Sexual reproduction allows for more genetic diversity by requiring two very different organisms to combine unique sets of genes, some of which are sex-specific, to create an organism that is genetically half of each parent. | 20 | 18 |
Why does infection cause increased blood sugar in diabetics? | I'm a type 1 diabetic and have been lucky enough to be very healthy, I recently had a pretty bad infection and the first thing I noticed was my blood sugar became near unmanageable. Why is this? | Infection leads to cortisol production leads to other variations of stress hormones, eventually leads to glucocorticoid stress hormone production. This leads to increased blood sugar release from stores in the liver.
Think about a non diabetic. There is an evolutionary need for increased blood sugar if you're fighting an infection. Your immune system cells will need more access to sugar in the blood to be able to help provide the energy they need to help fight off and kill bacteria/viruses, etc. This is sadly, counterproductive in diabetics.
If you're curious to learn more about stress responses, and the wide variety of downstream effects you should Google sympathetic nervous system and parasympathetic nervous system. Each category of nervous system responses leads to a wide variety of downstream effects. | 29 | 22 |
If light is produced by the release of photons when electrons return to stable energy levels, why do blackbody objects emit light over a continuous and wide spectrum? | Doing some light reading on the Internet and was reading up on black body objects and why objects glow when they heat. I was told that photons are released through the excitement of electrons, and then you have things with emission spectrums and so on. This implies that the spectrum should only have very specific wavelengths of light. However, I have looked at spectrum graphs of objects such as incandescent lightbulbs and found that they emit light over a continuous spectrum of various intensities that extend over a significant range of wavelengths.
Why is this so? Why are the emission spectrum wavelengths not emitted? What is it in the function of blackbody objects that make them emit light across a constant stream of wavelengths? | Charged particles emit a (quasi-)discrete spectrum of EM radiation when they transition between *bound* states, but they can also emit continuous spectra when they transition between *scattering* states.
This is what bremsstrahlung is, and that's ultimately what causes the continuous Planck spectrum of a black body. | 28 | 29 |
ELI5: How does your body know when to stop or start making blood? | Like after you donate blood (or have blood loss from some unfortunate event) what makes your body say "time to make more blood!"? What makes it say "okay I'm full on blood now. You can stop."? | You have cells in your body that can (approximately) sense how many RBCs you have, mostly in your kidneys, and these cells produce a molecule called erythropoietin to stimulate red cell growth. Conveniently, in the same organ, there are cells that can approximate how much liquid volume you have in your blood, and if you don’t have enough or have too much, it can balance out by getting rid of or holding onto water | 19 | 19 |
ELI5 why do humans need to eat many different kind of foods to get their vitamins etc but large animals like cows only need grass to survive? | In addition to the 'efficiently breaking down grass' thing, and the 'they eat a variety of plants' thing, there's also the fact that species typically evolve the ability to make vitamins that they can't get easily in their diet. For example, humans make vitamin D because there aren't many food sources of it, but we can't make vitamin C, but can find it in food. But other species can make their own vitamin C.
It's a trade off between needing to find a variety of food and not needing the cellular machines to make more stuff. | 13,781 | 34,298 |
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ELI5: In baseball how does the "Hidden ball" trick work, as seen on the front page today. | I assume a 5 year old probably doesn't play much baseball or any baseball at all, like me. Also, is it a 'legal' move to make? | In baseball, the ball is almost always in play. In other words, the defense is allowed to tag out runners between plays and the offense can steal bases between pitches. Normally when the fielders are concerned about a runner on base, the pitcher simply makes a pickoff throw, meaning that he throws the ball to a fielder covering a base, rather than throwing a pitch to the batter.
With the hidden ball trick, the fielders find some way to get the ball to a fielder covering a base without the runner knowing. As soon as the runner steps off the base, the fielder tags the runner with the ball. Since the runner is tagged off of a base, he's out.
Please note that there is one particular rule that makes the hidden ball trick particularly difficult. In the MLB, the pitcher can't touch the rubber (white area on the pitcher's mound where pitches are thrown from) after giving the ball to a teammate to hide. (Other leagues require that the pitcher can't be anywhere on the pitcher's mound.) This makes the trick difficult because it's harder to convince the runner that the ball's in the pitcher's hands if he's not standing in the place where he would normally pitch the ball. | 25 | 39 |
Why is seemingly every ML/CS paper posted on Arxiv and published as a conference proceeding, whereas most biology papers are not on BiorXiv and are published in actual journals? | I'm trying to understand the cultural/domain differences here. They seem like very different approaches to presenting research. | Machine Learning and Computer Science often view the highly selective conferences as the highest impact avenues for disseminating their work, more so than journal publications. arXiv also has a far more established presence in physics and mathematics, and ML/CS are much closer culturally to these fields than biology is. | 48 | 20 |
ELI5: How are moles and freckles formed? | There are cells in your skin called Melanocytes. These melanocytes produce something called melanin. The amount of melanin produced determines your skin colour. The more melanin you have, the darker your skin. When we are exposed to the sun, we notice that we get dark, or tan. This is because sun exposure cases the melanocytes to make more melanin to protect you from further sun exposure. So you end up getting darker (getting the tan you want). Lighter skinned individuals or people who are genetically susceptible, can have something slightly different occur. When exposed to the sun, they will also increase melanin production, but the melanin will not be distributed evenly. So you will have spots of increased melanin. These spots are what we call freckles.
Moles are similar. Moles are an overgrowth of melanocytes in the outer layer of your skin. Usually melanocytes are laid down evenly. When they form in clusters instead, they become moles. They are dark in colour because again: melanocytes form melanin which is the dark pigment of your skin.
TLDR; Freckles = uneven tan | 14 | 38 |
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Do photons (ie. light) possess the property of inertia, or inertial mass? | It seems surprisingly difficult to find an authoritative (layperson-friendly) answer to this. It's pretty obvious that a hypothetical box of photons will have a greater inertial mass than an identical-but-empty box, but can light be said to have inertia? | To talk about photons/light, it is necessary to invoke relativity. We can't use Newtonian mechanics to answer questions about things that move at the speed of light.
In relativity, photons are massless particles, where 'mass' is defined to be 'the energy that an object has at rest.' Photons are never at rest, but by carefully considering how the energy of a photon depends on its momentum, one can see that they have no mass. (The argument is roughly that E^2 = m^2 c^4 + p^2 c^(2), and photons have E=pc, so they must have m=0.)
[Sometimes, especially in older texts, one finds a different definition of mass which increases with speed. This is the 'relativistic mass' which is given by m=E/c^2 or m=m0/sqrt(1-v^(2)/c^(2)), where m0 is the 'rest mass' discussed above. Using the relativistic mass as what you mean by 'mass' makes certain equations agree with Newtonian mechanics at the cost of hiding what is really going on and making photons more confusing. The modern view is to forget about relativistic mass and always talk about rest mass.]
'Inertia' is something that is harder to quantify for a photon. If you just say that inertia is 'resistance to changes in motion' then yes, photons have inertia, because they like to keep moving in straight lines just like massive particles. If you try to define inertia quantitatively, like by inertial mass, then you say it's the resistance to motion for a given force; but F=ma doesn't hold in relativity, so it doesn't follow that photons have no 'inertia' in this sense. Note that physicists never bother saying whether or not something has 'inertia'; they'll just tell you what its mass is. That's the number that matters.
By the way, in relativity, systems of multiple particles have a mass that is, in general, not equal to the sum of the masses of the constituents. So a box full of photons does, in fact, have nonzero mass even though each photon is massless. | 31 | 49 |
How does a social science education shape students' political views? Do they become more/less conservative/liberal? Do different social sciences affect students' political ideology differently? | Is the average Political Science graduate more left-leaning than when she began studying? Does an Economics student become more right-leaning? And so on...
If yes, how do different fields affect the students differently (why does the econ graduate become more conservative the sociology graduate)? | I agree that this is going to be a tough question to answer.
Here are some elements you'd need to start with.
1. Take a university. Worry about external validity (across uni's) later
2. Poll all students for political beliefs before freshman year
3. Watch the ones that go into social science
4. Poll those kids after their social science courses
5. Figure out how to deal with majors switching later (from one social science to another, or dropping out, or "dropping in" after a few years of STEM)
6. You now have a pre-treatment dataset (from before the freshman year), a treatment (social science courses of varying stripes), and post-treatment evaluation. Of course you'd need a control group - those who didn't take social science courses? Seems problematic, but what else do you do? With just social science students, you can at least do a test of differences. Maybe put demographic stuff on the right-hand side at minimum.
7. Of course in this case, your population is "university students" and the specific subgroup you care about is "uni students who majored in social science of varying stripes." If you cared more broadly about "early 20s individuals," you'd need prior data on the political beliefs of 20-somethings more generally.
Somebody in labor econ or the economics of education might know of studies along these lines? | 21 | 52 |
[Last Airbender] Even an average bender is capable of pretty mammoth acts of destruction. Why, then, do any major cities still stand? A motivated Earthbender vandal or Firebender terrorist could do very extensive damage in only just a few minutes. What prevents this? | For the problem of vandals: Mastering the art of bending is one that involves self-discipline and spiritual enlightenment. It rewards those with patience and will more than impulse. Though there are numerous bending triads in Republic City, there is a difference between organized crime (where the main goal is profit, usually, over mayhem that can be traced back to you) and destructive terrorism.
Now, during the 100 Year War, the Water Tribes were protected by their remote location, and the Earth Kingdom is heavily fortified at it's edges to prevent invasion. A spy would need to be well-trained indeed to infiltrate into the Earth Kingdom far enough to find a truly valuable target that would merit his giving up any disguise to set it ablaze. Not to mention Earth Kingdom settlements are, naturally, composed primarily of earth and stone, not materials that tend to catch fire easily. | 34 | 30 |
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ELI5: Why aren't refrigerators placed against the outdoor wall with a ventilator that just lets in cold air if the temperature is cold enough outside? | Wouldn't electricity be saved if refrigerators were cooled down with outside air when the temperature is cold enough? | Refrigerators, just like air conditioning, are not just about keeping things cold. They also keep things dry. By letting in outside air, the humidity levels in your refrigerator would rise, which would cause food to spoil much more quickly. | 22 | 22 |
[Batman] why doesn't batman camouflage his whole face? | If stealth and his secret identity is so important, shouldn't he camouflage his jaw? It would make him harder to aim at and obscure his skin tone. | People have given good practical answers here, but there’s another element to it as well: the answer Batman gave to Joker when he asked the same question-“to mock you.”
Batman is supposed to be a terrifying force of nature to the cowardly and superstitious criminals, those who would prey on the innocent and harm the weak for their own benefit. But to those in need, the people of Gotham Bruce is trying to protect, the exposed jaw shows them that he’s not a demon or monster, but a person who wants to help and save those who need it. To Joker, someone who believes in the inherent evil of humanity, seeing this contradiction of punishing avenger and compassionate hero, a dark knight trying to save the city by fighting evil on its own terms, this is a spit in the face to everything he believes. | 43 | 16 |
ELI5: Why is swelling bad for healing? | I get why swelling is painful/inconvenient. What I don’t get is why doctors recommend things to reduce swelling of an injury even if pain management isn’t an issue (unless they just assume it is). Isn’t swelling part of our bodies natural response to protect/heal an injury? | Swelling is actually good for healing, especially in the first 48 hours of injury - as it increases the blood supply to the injured area. Blood brings oxygen and other nutrients which the tissues needs to effectively heal. However, it is a balancing act. Swelling increases pressure to the injured area, which is one of the ways we perceive pain, so managing swelling helps more than you think to manage pain. The other consideration is that too much swelling might prevent/restrict movement, and this aside from being really uncomfortable, decreased blood flow to the area. | 63 | 50 |
[Comic Books] I am just an average human being, but there are plenty of superheroes around me. Is there anyway I can ascend to godhood and outpace them? | There exist many ways to become empowered, but they are all risky.
Your best bet is likely to become an archeologist and track down a lost item of power. Note that even some of them have side effects (see Fate, Dr - Helmet). | 32 | 35 |
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Why do we take anti-inflammatory medicine for an injury. Isn't your body inflaming the injury to promote healing? | You are 100% correct in saying that inflammation is the body's way of promoting healing. However, inflammation can be categorized into one of two types: acute and chronic.
Acute inflammation is "healthy". It promotes healing.
Chronic inflammation is "unhealthy". It is the body over-responding to a situation and it begins to cause itself harm.
Anti-inflammatory medication is not given to acute inflammations. They are usually given for chronic inflammation to prevent the body from hurting itself from the over-reaction. | 14 | 40 |
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An infinitely long line made into a circle? | My question might be odd but i can't figure it out or come to a conclusion.
So if i had an infinitely long line and turned it into a circle, the circle is infinitely long but has to end because a circle is a closed loop. Infinity can't end tho, as it goes on forever?
Or am i just misunderstanding something?
Any thoughts and answers are appreciated, thanks! | In math, there are many different notions for "geometry" and how to talk about shapes. What we're generally used to from high school math is "Metric Geometry", which has to do with lengths and distances and such. On the other hand, there is a type of geometry known as "Topology" which does not give a shit about lengths and distances and only cares about "shape".
If you have an object in Metric Geometry, then you can move it around and rotate it and it won't change. These are "isometric" transformations because they don't change lengths or anything, and so Metric Geometry says that they're actually identical. If you have an object in Topology, you can also move it around and rotate it, but you can also stretch it, bend it, compress it, flip it in a mirror, etc you can do almost anything as long as you don't tear it. So Topology sees more things as being the same than Metric Geometry does. Eg, a square and a circle are the same thing Topologically, but not the same thing "Isometrically" (ie in Metric Geometry).
Now, to the question at hand. Say that you have the interval (-pi,pi). It's short, so you can first cap it off into the closed interval [-pi,pi] and loop it into a circle by gluing together the end points. You then get a normal circle of radius 1. This isn't done, specifically, through rotations and translations, but it does preserve lengths in our object. Now, here's the thing, since length doesn't matter to topology, the intervals (-pi,pi) and (-∞,∞) are the same topologically. In fact, the function 2arctan(x) compresses (-∞,∞) onto (-pi,pi) perfectly topologically. So, topologically, you can totally redo this process of creating a circle beginning with (-∞,∞) because, to topology, it's not infinitely long, it doesn't even make sense to talk about length, and it's exactly the same thing as (-pi,pi).
So, through the process you describe, you can create a circle when you look at things through topology, and that's good. It's also a square too. But if we track the lengths of things, then we don't get a circle through the lens of Metric Geometry. This is because it doesn't have a well-defined radius or circumference that is constant throughout. Moreover, we can try to associate angles with arclengths, while keeping length same throughout, and we get a nonlinear relationship between angle and arclength, going to infinity at the "top" point of the circle, which is not a property that circles have in metric geometry.
So, yes, you can make a circle. But you have to be careful about what context your circle exists in. | 26 | 16 |
ELI5: Coming from the Philippines, how does a welfare state like Sweden work and how is it that third world countries like us can't do the same? | Lots of countries, including the Philippines, do have welfare and social service programs but ensuring access and distribution is always problematic. Graft and corruption are usually the biggest barrier, but another major issue is simply a lack of civic education.
The people who most need welfare are also the most likely to not know their rights, how to apply for these programs, or even that these programs exist. | 15 | 19 |
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[Dawn of the Dead 2004] Having access to an entire mall, was there a way the group could've used the malls resources to turn it into a safe, permanent, and sustainable settlement? | Provided they were smart and started more or less immediately after moving in: potentially.
- set up gardens on roof. Set up water collection system on roof. Solar panels would be great but as they're not common in malls I'll assume they weren't an option.
- repurpose pet store products to create fish farm, potentially also small animals such as guinea pigs (can be fed on grass alone and grow quickly) and birds depending on foodsource availability. Goldfish would likely be your best bet as they can live off a fairly wide range of food, grow quickly and can get pretty huge if you've got the space. Utilize pool supplies/indoor fountains to this purpose however you could also build your own 'tanks' using pipes to create frames then water sealing with tarps. These wouldn't need to be deep, only large, in fact an ankle deep pool would be easier to maintain and a better option in terms of water use
- secure and fortify the underground carpark. Harvest all gas from cars in order to power generators.
- develop an armored vehicle not dissimilar to the one they use in the film, however designed specifically to scavenge/transport gas.
I'd see the use of gas to power generators as a short term solution as there's simply going to be a point where you run out, so you'd need to utilize it to promote rapid development at the beginning of the project. Focus on setting up a wind-based power harnessing system (again, on the roof) to support long term energy needs.
It'd be a lot of work, would take some time before it was a sustainable system and certainly wouldn't be a perfect option but it could be doable
*edit expanded thoughts on farming | 157 | 176 |
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[Lovecraft] What's the deal with the Dreamlands? | So it's this other world we go to in our dreams, but people seem to live there. The story about the town of Ulther, where no man may kill a cat, suggests that there are whole cities of people living there. Are they dreamers too? Do they live, die, sleep and eat? Do they know they live in a dreamland? Can you dream there? | Dreaming is how human consciousness can enter the Dreamlands, other beings may be able to enter in other ways or may have developed there themselves. The Dreamlands are a real place with real inhabitants, though human perception of them may be extremely skewed and unreliable. | 23 | 47 |
What is Critical Theory? What are critical theories? | Definition? Requirements? Are philosophers who call themselves "critical theorists" actually ideologues in disguise?
Also, other than the SEP and IEP, what would be some good resources for getting a very intimate understanding of Critical Theory/critical theories? Books? Talks? Specific individuals?
I suspect answers from people with critical theory and political philosophy flairs would be especially helpful. :) | Critical theory typically refers to the work of thinkers who identify with neo-Marxist thought. In general, this work is devoted to explaining Marx's great failure: the predicted communist revolution that wasn't. Much of critical theory is devoted to explaining the nature and impact of ideological hegemony--the mechanisms of power and control the keep wage workers happy with the current system.
Contemporary critical theory often allies itself with feminist, post-colonial, and other emancipatory approaches to philosophy.
Critical theorists might be described as ideologies, but they are certainly not "in disguise." A central tenet of most critical theory is the idea that every philosophy has an agenda. If that's true, then critical theorists are more honest with their readers (and with themselves) in making that agenda apparent.
Slog through Althusser's Ideology and the State for a good taste of classical critical theory. Watch The Matrix movies for a somewhat accurate gloss of Beaudirillard. Watch Fox News for critical theory in action. Ironically, Fox News is probably one of the most successful and widely known ideology critics available. | 19 | 22 |
[Jurassic World 1 and 2] What would make dinosaurs more superior in military combat than any other animal? | If you could genetically modify a create to obey commands why not an attack dog? Little easier to defend if it turns on you? | Military procurement is about more than just what the military needs to be effective. Dinosaurs are *cool*, and the politicians who make budget decisions can be swayed by such things. It's happened many times before. And the public will think so too, which means there is propaganda value in it. Finally, it provides a funding source for the fundamental tech being developed and intimately connects it with the military. Even if the dinosaurs you see are dumb and impractical as a weapon, they are an impressive proof of concept for the *potential* of that brand of mad science, and lessons learned can be applied to future endeavors. | 218 | 197 |
ELI5: Why do ants and insects get trapped in pen circles? | [Example](https://www.youtube.com/watch?v=W_sSx54aIYI)
[Another example](https://www.youtube.com/watch?v=DcPHP24zxOw) | There are a few different explanations for this, depending on what the circle is made of. Ants will get trapped in chalk and baking soda circles, as well. A big contender is that ants travel largely by a scent trail left behind by other ants. If you watch ants coming for pieces of food left on the floor or the sidewalk, you'll see that they take the same route. A circle made of something like ink or sodium bicarbonate or chalk can disrupt this scent trail and cause almost a wall of sorts. | 65 | 159 |
What makes definition of a word the "correct" one? | Greetings everyone. Let me elaborate and give you some context for the question posted above:
Quite some time ago, on another subreddit, one of the users created a post titled "Should we cure aging?", with a video of 40 minutes long attached, where he expressed his thoughts on the matter. Now, what is generally meant by aging in the context of life extention is senescense - gradual detirioration of organism, that leads to loss of ability, reduction in quality of life and general survivability. Curing this basically means reverting that damage, so the person is young and healthy again, and ideally making it so that it stays that way for as long as they want to live. Certain another user did the following: He produced a definition of aging that included EVERY PROCESS that can be expected to happen "naturally" in human body over the course of life, from gestation to senescense and death, including even something as optional as pregnacy. Then he declared that definition to be "THE CORRECT DEFINITION" and aggressively dismissed anyone who dared to not agree 100%, utterly ignoring what the OP meant. Based on that definition of his, he then proceeded to "prove" that curing aging is impossible "by definition". Which of course says nothing about the practical possibility of achieving what was meant by the OP. So i have these questions to ask:
**1) What can make a given definition the "correct one"? Are there any objective criteria?**
**2) How can one demonstrate, that one definition of a word is better than another to convince someone to accept it?**
3) What is it called, when a person concludes that something about a thing is impossible in practice, based solely on the definition that they gave to the word that denotes it? For example. somebody points at a house, and says "it is a house", then he gives the following definition of "house" - "any construction that can't burn". Let's imagine that this is his house, and suddenly it caught fire. You are pointing that to him, and he dismisses you, saying "That's asinine. My house can not burn BY DEFINITION". It's propably a known and researched fallacy, i just don't know the name of it.
Thanks in advance. | A lot of important philosophical disputes sometimes turn into “terminological disputes” like this one. One thing that often helps is to clarify all possible definitions someone could mean, explain which you will focus on, and then argue based on that. In the “aging” example, someone *could* go on to keep using a different definition than yours, but as long as you agree “we should stop “aging” in sense 1 but allow “aging” in sense 2”, then it doesn’t really matter which one you *call* “aging”.
But sometimes, particularly with bedrock normative vocabulary like “right” and “wrong”, you can’t just concede the term to the opponent and use a new one. Those situations are rare though. | 35 | 66 |
According to contemporary philosophers, which aspects of Kant's transcendental idealism are most tenable? | How much of the original theory has been abandoned or modified? | The answer is: it depends on who you ask.
I think the majority position is that 19th and 20th century developments in mathematics and physics really put a damper on Kant's transcendental aesthetic and *some* of his views about logic, mathematics, etc.
On the other hand, no one in their right mind would say that the Kantian position in metaethics is dead. His views on science, though much more fragmentary, also have continuing relevance.
It's also worth pointing out that even if Kant's views themselves have been abandoned, he's still one of if not the most influential philosophers of all time. Both the "analytic" and "continental" traditions (I don't think there's any sharp distinction here, but whatever) are born of Kant and Kantianism. Until relatively recently, one could with a fairly high amount of accuracy claim that one was either with Kant or against him: he was the single most important touchstone for philosophy until at least the 1950s. | 10 | 18 |
Why is it wrong to value strangers as much as you value your loved ones? | Every stranger you see has a life that could be richer than yours or anyone you know. They may be more righteous. There are millions of starving children, why do they come after your own? | Utilitarians would argue that it doesn’t matter. But for me it’s because we have an intuitive feeling of obligations based on proximity. Yourself, your loved ones, your friends are all people that you have moral obligations for. You can’t just stop feeding your dog because you’re giving the money to a charity that saves children’s lives, even if that would be a moral action purely based on utility. Why this is the case is harder to argue because it rests on the assumption that obligations actually matter. If you don’t have this presupposition then it is very hard to convince you as it hits the bottom of what assumptions should be taken as intuitive truths when dealing with morality. | 46 | 49 |
Eli5: What causes leaves to fall off trees? | Obviously gravity, as well as the leaf dying as the tree moves into its dormant phase. This morning I was outside before the sun came over the horizon. It was pretty windless, and cold, and the Norway maple in my yard was holding its leafs. 10 minutes after the sun hit the tree, leafs started falling down very regularly, as if it was snowing.
My theory is that there is a small scale freeze/thaw cycle that encourages the leaf connection to weaken, causing the snowing effect I witnessed. I’d love to learn more! | When temperatures drop and the days shorten, trees detect that and produce a plant hormone called ethylene. Ethylene signals the leaves to stop growing, break down their chlorophyll and send nutrients back to the tree, then die. At the same time, a plant hormone called Abscisic acid (ABA) starts to form an abscission layer—a small area at the base of the leaf that’s designed to break easily and cleanly so that the leaf drops without breaking anything in the twig. Once the tree has retrieved any nutrients it can from the leaf and the abscission layer is complete, the leaf will drop without much force. A gust of wind or a change in temperature or a little rain will snap off the dead leaf on the breakable abscission layer. | 53 | 32 |
How do potholes form? | Potholes are never gradually descending, which seem counter-intuitive. How do they form then? | Modern roadways are paved with either two materials: cement concrete or asphalt concrete. Both construction materials contain two portions: a binder and an aggregate. The inclusion of an aggregate makes the material a "concrete" the only difference between the two is the binder (concrete or asphalt). Once these materials are poured and they "set" they are solid materials, but they can still deform by slight amounts. Cars continuously driving over these surfaces result in continuous compression (car tires driving over it) followed by relaxation (no car). Constantly. Load/no load. Load/no load. Day in, day out, year after year after year.
Roads rarely, if ever, fail from sudden collapse unless the subgrade beneath the road suddenly falls away. What actually happens is just the accumulation of minor, tiny imperfections introduced into the surface from traffic driving over it.
So, potholes are really the extreme versions of these minor imperfections. A slight deformation is introduced by a car driving over it and a tractor trailer drives over it and exacerbates the problem even more creating some sort of fatigue cracking in the surface or the asphalt binder may relax a bit and start to form a rut.
Surface cracking, rutting, or other deformations will just get continuously worse over the years. Rain will get in between the cracks, freeze, and make them worse, or maybe just the road hasn't been taken care of for a few decades and the minor cracks meet up together to form a larger continuous crack. Then it's just time and cars that widen the crack further and further until some other type of failure is introduced and viola: pothole.
**TL;DR time and energy and the accumulation of a bunch of minor effects all combine to slowly but surely destroy everything you hold near and dear** | 12 | 24 |
ELI5: Why do certain muscles spasm randomly when doing a simple task like just picking up a backpack that you’ve picked up before fine but after it feels really sore? | I don’t know if it’s muscles I’m talking about or another part of the body - I can’t think of right now sorry. I went to pick up my work backpack the same as I do everyday, but yesterday and my shoulder more so like neck area completely spazed and it was a burn. I hate that feeling. Today my neck and shoulder are so sore why does the body do that? Is it the same as a Charlie horse?? | Basically when performing easy tasks you are less focused on doing them and more apt to injure yourself by doing something incorrectly form wise. Many people end up with slipped disks and back muscle spasms just from bending over to pick something off the ground | 10 | 36 |
How do scientists discover new ways of combating diseases? In other words, how do scientists determine how and what to start looking for to cure diseases like HIV/cancer/etc.? | I understand the scientific method, medical studies, and that sort of thing to determine whether a particular method of combating a disease is effective. What I'm having a harder time understanding is how we even begin to figure out that 'such and such' virus or bacteria or antibiotic or whatever is actually really specifically useful in getting rid of another particular kind of bacteria/virus. | The major challenge in finding a new way to combat a disease is understanding the biology that underlies the disease itself. The approach to finding an answer to a biology question is rarely clear, and depends on the question being asked in the first place, so your question can only really be answered on a case-by-case basis. When we're looking for ways to treat a disease we therefore usually only have a partial/incomplete understanding of a disease, which tends to come back and bite us in clinical trials. Still, since it will be an extremely long time until we will be able to say that we 'fully' understand any disease, and we need treatments now, the show must go on. In pharma, there are two major drug discovery approaches: High throughput screening and rational drug design.
You can run a high throughput screen without even understanding very much about the etiology of the disease you are trying to combat. All you need is a decent model for your disease that you can grow quickly and at a small scale--if you are fighting a bacterium, you can use the bacteria you are trying to fight. If you are looking for a molecule that affects cancer cells, you can grow cancer cells in plates. Then, you can take a big library of different molecules (think: millions of different compounds at a big pharma company) and just try them all at a very small scale to see if any of them work. If you have a good model you can run these screens efficiently enough so that the effort is worthwhile. Taxol is a great example of a blockbuster chemotherapeutic that came out of a high throughput screen. The major drawback to running a high throughput screen is that your compound library is often untargeted, so you have no way of knowing if you are even barking up the right tree unless you work out a lot of the biology surrounding the disease first. Also, even though the sheer number of compounds in some of these libraries is very large, they often are biased towards compounds that are easy to make from a synthetic point of view, and therefore often do not cover as much 'chemical space' as the big number might lead you to believe.
Rational drug design requires a bit more knowledge about what molecular mechanisms underlie the disease in the first place. If you know that stopping the function of some protein would prevent your infectious microbe from being viable, or mitigate the growth of your tumor, then you can use your knowledge of chemistry to design a drug that will simply bind to that protein very tightly and stop it from functioning properly. This is a lot easier said than done--it is pretty tough to predict how a molecule will bind to a protein, and most of the computational models that we have to help us out are barely coming into their own. This approach has still been very successful though; Gleevec is the poster child of rational drug design and a quick read of its development history will probably give you a better idea of how rational drug design works.
| 14 | 33 |
If photons are mass-less, then why does gravity affect light? | How does gravity affect mass-less particles? | Gravity isn't just an attraction between masses, it's the way the paths-of-least-resistance through space and time, which light follows, are modified by the presence of energy. So, the "straight line" path that light follows gets curved by the presence of a star or planet. | 162 | 194 |
Isn't all human activity technically natural? Why do we classify it as something that seems out of this world? | The point I'm trying to imply is that humans were created by nature, and thereby humans using land to build homes is no different than a beaver building a dam, and a human building factories is no different than a bee creating a hive.
Why do we treat human activity like something so totally different, like land use, than animals have in the past?
By the way, is there a name for this viewpoint? | This is almost exactly what John Stuart Mill says in his wonderful essay *On Nature*. He first points out that the term *natural* often connotes something positive or desirable -- something that we by default ought to respect. But he sees a dilemma with the concept of *nature* and thus with the normative force typically ascribed to it.
First, *natural* could mean anything that occurs outside of human activity. On this view, beavers making dams, bees creating hives, and birds preparing nests are all *natural* whereas the full range of human creation is unnatural. If we accept this, then there can be nothing normative about the term *natural* because it simply describes everything that occurs without human agency.
On the second view, *natural* refers to every part of nature -- including humans. In this case, everything we do would be seen as natural: building skyscrapers, designing houses, engineering bridges, and the like. Here, again, the concept of the *natural* carries no normative force, since it includes *everything* humans could possibly do, and thus makes no room for "natural" and "unnatural" activities.
If you haven't read *On Nature*, definitely find it online if you can. It's great! | 39 | 52 |
Using work without permission | My former advisor published a paper I wrote without requesting permission or making me an author. I am in the credits.
I had submitted the paper and gotten it accepted but was unable to do the experiments requested to finalize it and set it aside.
The text is about 70% similar to the version I submitted, and I have correspondence showing I was the corresponding author and that I was expected to do the writing, as well as a version history.
I don't expect or want to get any compensation out of pursuing this but I want to take this as far as I can. This is not the first time he has done something like this and I feel like I have some responsibility to students who are currently in or may enter his lab, as this is not an acceptable way to treat them and I don't mind spending some money to do it.
It was suggested I hire an attorney to write a letter, are there attorneys who specialize in this sort of law?
Anything else I should pursue beyond letter writing?
Thank you | 1. Was this published into the same journal that your version was accepted into?
2. Was it part of the same submission, or did you need to withdraw/fail to meet a re-submission deadline?
3. Was this an undergraduate advisor? Masters? PhD? Employer?
I would suggest that if you want to pursue this, you involve your institution's ombuds office rather than a privately retained lawyer. | 16 | 36 |
CMV: We should be aiming to understand and discuss with each other more, and be outraged less. | There have been a lot of horrible things going on lately. A ton of hate and bigotry and divisiveness, the reaction to which (understandably) has been anger and outrage.
My view is that in the face of a bigoted/ignorant statement, in an ideal world, we would try and understand and discuss the ignorance and create an ally going forward.
I’ll take the NFL Player Desean Jackson’s, antisemitic social media post for example (partly because it seems this has drawn less attention or outrage than other recent events).
Julian Edelman (a Jewish NFL player) responded not with anger and outrage, but rather extended an invitation to visit a Holocaust museum, to which I understand Desean accepted.
This is literally the best possible response in my opinion, instead of attacking Desean and forcing him to defend himself, you’ve hopefully created an ally in the fight against antisemitism.
All the while, we see bystanders on twitter and Instagram calling for outrage and anger from the general public.
To be clear, my view is NOT “People should calm down, it’s not that bad”. It’s asking a lot, especially for people who are directly targeted by hate and bigotry, to think calmly and rationally in the moment (they’re being attacked after all). But in an ideal world, the initial response to a bigoted statement should not be outrage and attacking those who made the statement, but rather an understanding and discussion with that person. | A friend? A colleague? An acquaintance? Sure, have a discussion with them.
Everyone else? Hell no. Having a rational discussion with an irrational bigot is not only an exercise in futility, it legitimizes their bigoted views. Bigots *want* others to address their bigotry, to talk with them about it, so they can espouse their bigoted views. Why would you ever want to give them that opportunity? | 19 | 194 |
[Mathematics] How can I store multiple integers as a single value? | So I'm a programmer and I had a thought.
There are functions I can use to store a value between program states, but I can't store a list of values.
If I have 2, 8 and 15 and I want to carry them between states, I'd have to store 3 values, but is there a way to use a calculation that I could reverse that would produce a single number, so I could get the values back after?
I could store 2, 5 and 7 as 257 and have the program decipher it to return 2, 5 and 7 but that only works for single digit integers, and long lists would produce a number too large.
The use of primes comes to mind but im unsure how, or if it's possible. Ideas? | If the values are limited in size you could store them by shifting the bits to the left as you go through the program (e.g. if they're limited by like 6 bits you can shift your second list element to the left by multiplying it by 2^6 ) and adding them together. Reversly you can “pop“ elements from the stack by usage of modulo operations (modulo (value;2^6 ) returns the last value on the stack and by doing value=(value/2^6 ) you remove the element you just read, assuming integer, so you can read the next one) Obviously you still have a limit for how many elements you can store and the “frame“ is static so you reserve the max amount of bits for a list element even if it doesn't use as many. Basically...the same idea you presented but by using a shift based on the binary basis instead of the base-10 system you should be able to save some space (And instead of only working for single bit integers it works for a wider range of values).
I believe you could get a much better answer on here if you can give people a little bit more context information. Usually when trying to “compress“ informations like this it's all about knowing which assumptions can be made about the stored elements, in what type of application they are used in etc. | 151 | 349 |
What are the best arguments against contractualism/social contract theory? | The most common criticism of social contract theory is that the character of the contract is merely ideal and hypothetical. There is no obviously no point in which a certain group actually gathers and mutually agrees on a contract that binds every and each participant. Theorists of the social contract have seeken refuge to either a formulation of Locke's argument for tacit consent, which is an implicit approval of the contract through actions that recognize it as necessary, or a presentation of it as a kind of a thought experiment akin to Rawls's famous original position.
Another criticism is that there is a complete disregard for beings that could be considered as non-rational, such as animals, people suffering through mental illness, and children. How can it be said that they would have rationally agreed on the social contract if they lack any capacity to do so?
There is also an issue with the fact that principle in which the social contract theory is based is highly abstract and cannot bind us morally, or guide our practical reasoning. | 66 | 61 |
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[Star Wars] Is there just something about force choking? | Why do they always go for the throat like that? Seems like there are a lot of ways to fuck with someone using the force. They could pinch a nerve, or squeeze their brain, or something... | Its an intimidation tactic, something clear, noticeable, and easily understood amidst a crowd.
>They could pinch a nerve, or squeeze their brain, or something...
These are all possible. In fact, you're referencing specific force powers like wound, kill, etc. You can even completely crush someone with the force, an act so violent, painful, and gross that it requires complete consumption by the dark side to accomplish (I'd assume even the average Sith would get a little queesy looking at that). | 70 | 63 |
Is there some "quick and dirty" supposed counterexample to virtue ethics, as there is to deontology or utilitarianism? | What I mean, for utilitarianism and deontology, there are a bunch of well-known examples that are at the very least meant to strongly challenge your intuitions surrounding those moral frameworks, and demand some kind of explanation. Usually something like the deontologists would have to say that lying to an evil person for the greater good is still immoral, and the utilitarian would have to agree that doing harm to a very small group of people for the enjoyment of a much larger group is permissible. The murderer at the door and brutal gladiator-esque games in Rome are common examples.
**PLEASE do not comment on whether or not these examples are ultimately convincing**, I called them quick and dirty for a reason and I don't care. I also don't care how well it ultimately works against virtue ethics. I just want to know whether some example like this exists, that seems to contradict the core tenets of virtue ethics. | The main objections involve showing (1) the virtues offer too little action guidance or (2) the virtues are culturally relative. Sometimes this can be showing by creating a dilemma and “showing” that the virtue ethicist can’t clearly choose.
Like in the lying murderer case - it seems like lying to the murderer is dishonest but telling the truth is disloyal to your friend. Both seem bad, if we’re using the virtue words correctly. | 40 | 42 |
What are the utilitarian responses to Bernard Williams criticisms of their theory? | If you have specific papers or books in mind, I'd like to hear those as well. | A lot of Bernard Williams' criticisms are rooted in very fundamental disputes over what constitutes a good theory of ethics and what we should expect out of our moral principles. So at the ground level you're either with him or you're not for some of these issues.
On the other hand, Railton's paper "Alienation, Consequentialism and the Demands of Morality" is a commonly cited response to his accusations that utilitarianism is self-effacing. | 12 | 19 |
Steps to becoming a professor? | Hi Academia! I'm currently getting my MS in Biology (Evolution and Ecology) and am trying to put together a plan for my future. I have 1 year left and then to defend my thesis. I will most likely go on to my PhD after, though I'm newly married so we have to figure out plans for a baby maybe in the next year or so and everything else as well. I enjoy research and recently discovered I really enjoy teaching people about biology. I answer a lot of questions here on Reddit, have done the same on other forums and mostly seriously love science. I think it's incredibly important and I like to pass that knowledge on! I'd love to become a professor and was wondering if anyone had any pointers? A few questions I can think of right now:
* I am not currently a TA or GA for my school, but will try for it for my PhD. I applied but didn't get it for my MS. Is it absolutely necessary though for future teaching?
* Do I need to take education courses or does it not matter if you have enough research from the PhD and Post Doc?
* What are the hardest parts about getting a position?
* Anything else I should know that I'm not even thinking of?
I know I've got a ways to go, but if I can start preparing now it'd be great. Any help is greatly appreciated. Thank you!
EDIT - I know there is a difference between teaching a classroom and just enjoying teaching in general. I'd like to split my time between teaching and research. | >What are the hardest parts about getting a position?
There are very, *very* few of them, and you'll be in competition with people who are more established than you. People with a solid grant history and a list of publications as long as your arm. | 17 | 19 |
The fundamental unit of electrical energy is the photon, not the electron? - "Misconceptions Spread By Textbooks for Electricity" | I found this resource ["Misconceptions Spread By Textbooks for Electricity"](http://amasci.com/miscon/elect.html).
I've read through it all and it says a lot of interesting stuff that I cannot confirm, one of which is the title. I can't ask just one question as they are all related, so I will provide some statements from it, so that you can hopefully tell me if they are legit.
How accurate is this resource? How accurate are these statements? It goes against everything I've learned.
---
- **Electric current is NOT a flow of energy, it is actually a flow of matter**. ELECTRIC CHARGES are a physical substance. ELECTRIC ENERGY is a wave that travels via a column of charge. ELECTRIC CURRENT is a flowing motion of the charge already present.
- "Charge" is the stuff inside wires, but usually nobody tells you that ALL METALS are full of charge. Always. A hunk of metal is like a tank full of water, and the "water" is the movable electric charge inside it. In physics classes we call this "the electron sea" or even "electric fluid." This charge is part of all metals. In copper, the electric fluid is the outer electrons of all the copper atoms. **The movable charge-stuff within metals gives them their silvery color.** We could even say that charge-stuff is like a silver liquid (at least it is silver when it's in metals.)
- **Amperes Are Not a Flow of Energy. The joules of energy flow ONE WAY, down BOTH wires**. The battery created them, and the light bulb consumed them. This was not a circular flow. The energy went from battery to bulb, and none returned. At the same time, the charge-stuff flowed slowly in a circle within the ring. There you have the difference between amperes and watts. **The coulombs flow slowly in a circle, while the joules flow rapidly from an "energy source" to an "energy sink"**. Amperes are slow and circular, while watts are fast and one-way. Amperes are a flow of copper charges, while watts are a flow of energy created by a battery or generator. But WHAT ARE JOULES? That's where the electromagnetism comes in. When joules of energy are flying between the battery and the bulb, they are made of fields. The energy is partly made up of magnetic fields surrounding the wires. It is also made from the electric fields which extend between the two wires. **The electrical ENERGY flows in the space around the wires, while the electric CURRENT flows inside the wires**.
- The charge-stuff flows extremely slowly through the wires, slower than centimeters per minute. Amperes are an extremely slow, circular flow. Inside the wires, the "something" moves very, very slowly, almost as slowly as the minute hand on a clock. Electric current is like slowly flowing water inside a hose. Very slow, so perhaps a flow of syrup. Even maple syrup moves too fast, so that's not a good analogy. Electric charges typically flow as slowly as a river of warm putty. **And in AC circuits, the moving charges don't move forward at all, instead they sit in one place and vibrate.** Energy can only flow rapidly in an electric circuit because metals are already filled with this "putty." If we push on one end of a column of putty, the far end moves almost instantly. Energy flows fast, yet an electric current is a very slow flow.
- What then is electrical energy? It has another name: electromagnetism. Electrical energy is the same stuff as radio waves and light. It is composed of magnetic fields and electrostatic fields. A joule of radio waves is the same as a joule of electrical energy. How is electric current different than energy flow? Let's take our copper ring again; the one with the battery and the light bulb. The battery injects joules of energy into the ring, and the light bulb takes them out again. Joules of energy flow between the battery and the bulb. They flow at nearly the speed of light, and if we stretch our ring until it's thousands of miles long, the light bulb will still turn off immediately when the battery is removed. Well, not IMMEDIATELY. There will still be some joules moving along the wires, so the bulb will stay on for a tiny fraction of a second, until all the energy arrives. Remove the battery, and the light bulb goes dark ALMOST instantly.
| EE PhD here. Some of these statements are helpful and some are not. Much of the terminology is confusing. You are correct that much of the teaching in textbooks is simplified for understanding. Electrons move through wires via collective motion, like a newton cradle, not a racecar. All the stuff about the difference between current and energy is a bit of a stretch. Electrons carry energy, currents transport electrons. We weren't that misled in our youth. The fundamental unit of electrical energy is the electron-volt or the joule. Electrons can turn their energy into photons by finding lower energy states though. You could make a case that a photon is simply the realization of an electron's energy. For the most part, this website is confusing more than it is helpful. | 46 | 55 |
ELI5:Why is it so hard to NOT read subtitles? | Whenever I go to the cinema to watch a movie I have to focus to not read any of the subtitles since I don't need them. | Visual perception in the outer regions of our visual field reacts mostly to movement and changes rather than clear vision (so you would see a danger in the corner of your eye and be able to react to it). Focusing on the center of the screen pushes the subtitle into the outer region of your field of vision, making it trigger that effect - ie you have an instinctive urge to look down any time it changes. It takes conscious effort to suppress that. | 17 | 17 |
Where do yogurt companies get their cultures? | Do yogurt companies have microbiology labs? Do they try to select for/genetically-engineer strains? Wikipedia says yogurt is made by *Streptococcus thermophilus* and *Lactobacillus bulgaricus* (and maybe a few others). I also know that yogurt has been around for centuries (maybe thousands of years?)... So are we using the similar methods they used to use to procure the culture or are we using labs? I understand this is somewhat of a history/anthro question but does anyone know exactly how they got their culture in ancient times? Did it somehow just happen once, and then we started using the yogurt to make more yogurt (then maybe recently we started isolating the cultures from the ancient yogurt line)? I find it interesting to think that the strains we use today could actually be pretty different genetically than the original ones.
Edit: Just saw in the rules that the post must be based on something from a peer-reviewed journal. If this is the wrong place for this question, I'd really appreciate someone telling me where it should go. Thanks. | The big companies buy their cultures from a lab, just like cheesemakers, winemakers, breadmakers, and everyone else.
Yogurt was made before microbiology by using old yogurt to kickstart new batches. It will basically stay alive forever if you keep feeding it.
It was likely "discovered" just how yeast was discovered. Someone noticed that if you left milk sit out, its texture changes and it tastes different...and if you add that to more milk, that does the same thing! Shaboozle ya noodle, yogurt.
| 104 | 241 |
Is the surface of the ocean relatively flat (i.e. the biggest difference in height are waves and the occasional storm surge) - or are there notable peaks and valleys? | This may seem like a stupid question but given the vast network of oceans and waterways in the world I really was curious if you were to look at a cross section of all of the ocean's surfaces, would there be notably higher areas than others? | Due to water’s cohesion, mountains on the ocean floor can cause a measurable bump on the surface. It would not be noticeable from a normal person’s point of view, though. The moon’s gravitational pull and the earth’s rotation also cause the oceans to be deformed. | 10 | 15 |
ELI5: If allergies, and especially anaphylaxis, are so common, why do we still need prescriptions for epi pens and such? | >If allergies, and especially anaphylaxis, are so common, why do we still need prescriptions for epi pens and such?
Prescriptions are used to limit dangerous chemicals/medications to the use of folk who 1. need them and 2. have been instructed on how to use them by a physician.
Whether or not they are commonly used or required doesn't factor into it. | 66 | 35 |
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Why do we hear that they discovered water on Mars every month? What is different each time? | It seems like once a month or so, evidence of water on Mars makes headlines.
Why is something that has been known for a while newsworthy? What additional information is being discovered each time?
Even just a few examples would be helpful, if possible. | There are lots of different types of water, and different types of evidence. The evidence can be more or less persuasive, and imply water existed at different times.
So, you can find evidence of ancient, brine like water. Or ancient, acidic water. Or ancient, neutral pH water (note that evidence of all of these have been found). Or modern subsurface ice. Or modern subsurface brine. Or features indicating rare occurrences of liquid on the present day surface. Or clay minerals that are probably formed in water, but we can't be sure. Or evidence of water eroded features like rivers and lakebeds. And so on. Each tells a different facet of the history of water on Mars, and the planet's potential habitability. | 41 | 58 |
CMV: It is impossible to fully believe trans people *and* claim that gender is a social construct, without logically contradicting yourself | When reading about the topic of gender and sex I discovered what I think is a contradiction in some people's worldview. I am therefore curious if this point holds up to criticism, or if I Just missed something. To avoid confusion, here are my own opinions on these matters:
1. Trans people are neither mentally ill nor lying about their gender identity. And both trans people who do and do not choose to transition are 100% valid. I do not see either of these points as debatable.
2. A large part of your gender identity is socially constructed, however another large part is determined biologically. The view I am thus arguing against here that 'gender' can be defined as \*entirely\* a social construct. And yes I am aware that a lot, if not most, people don't hold this view. However there is a significant number of people who do.
​
Now to my actual argument:
A lot of trans people choose to make physical changes to their body, because they believe their body will then match their gender identity better. So why would they have this desire if gender identity is entirely determined by socially constructed gender norms? The way I see it, there are three posibilities here:
1. Trans people are "confused", and do not realise they do not need to change their bodies to identify as a different gender.
2. Trans people only make changes to their bodies because certain bodily aspects have become part of socially constructed gender norms. In a fully egalitarian and inclusive society they wouldn't feel the need to do so.
​
3. Your gender identity here isn't entirely determined by social factors.
​
If you answered 1: Many trans people suffer a lot less from their gender dysphoria after surgery or hormone treatments, that wouldn't make any sense if they were just "confused". Besides, if anyone would know what trans people want or ought to want it's trans people themselves.
If you answered 2: A fully egalitarian and inclusive society wouldn't have \*any\* gender norms. If being trans was only about performing a gender role, it would thus be impossible to even be trans in such a society. I also find the notion that being trans just means identifying more with the societal gender role your society has traditionally associated with the opposite sex is highly problematic. It de-legitimizes the transgender identity as mere 'preference' when in fact it is something you intrinsically \*are\*.
Thus option 3 seems to be the only viable option: many aspects of our gender identity or socially constructed, i.e. 'girls like pink and boys like blue'. However it does seem there is a much more fundamental sense in which we \*are\* a boy or a girl (or neither) that is much more fundamental than any socially constucted gender role.
Did make any mistakes in my reason? Or is there a 4th option I missed? Let me know! | The claim that gender is a social construct is not the same thing as the claim that "gender identity is entirely determined by socially constructed gender norms." While the latter is inconsistent with the existence of trans people, it isn't what people actually mean when they say gender is a social construct, so that inconsistency is not really relevant.
To make an analogy: money is a social construct. But that's not the same as saying that the amount of money that you have is entirely determined by socially constructed financial norms. Or: football is a social construct. That's not the same as saying that the winner of a football game is entirely determined by socially constructed sporting norms. | 13 | 17 |
How do chemical reactions work on the quantum level? | I'm an undergrad student studying chemistry and biology where (especially in organic chemistry) we do a lot of "arrow pushing" (i.e. drawing arrows to signify where electrons travel during a chemical reaction). Earlier today I was watching a video in which Sean Carroll (physicist) goes on to explain how electrons actually form a "cloud" of probability around an atomic nucleus, where according to its wave function you can predict where you might find that electron if you went looking for it. He also stated, most importantly, that the electron is actually just a cloud of probability until you look for it, that the electron isn't anything more than a wave function until we look. What does that mean for my arrow pushing? If the electron is just a wave function does it collapse when chemical bonds are formed? What exactly goes on in this sense? | Arrow pushing is a way of visualizing the quantum processes. When you push two electrons from the valence shell of an atom to an "empty" orbital of another atom, these blend to make a new bond.
For example, you can take two electrons from an s orbital and put these into an empty s orbital of another atom. The spherical cloud of each s orbital then blends together to form an oblong sigma bond cloud of probability. The sigma bond is now just as the original s orbitals were a cloud that describes the probability of finding the two electrons in a given place.
Basically, the orbitals, which are clouds of probability, blend together when you push the arrows, so to speak, and create a newly shaped cloud of probability that spreads out between the two nuclei.
This is nicely illustrated by two p orbitals interacting. For example, if you are forming an alkene, you already have a sigma bond between the C atoms. The p orbitals then can interact, through for example beta elimination, and form a pi bond. The p orbitals' clouds of probability have an hourglass shape, and the resulting pi bond (or double bond) looks like hotdog bun that wraps around the sigma (single) bond with no probability of finding the electrons on the C--C axis, just as the p orbital has no probability of an electron at the center of the hourglass.
So a chemical reaction creates a new wave function (sigma bond), a new cloud of probability. Collapsing the wave function refers to observing where exactly the electron is at any particular moment. This means that you no longer have a cloud of probability, but an actual measured location for that electron. In a sigma bond, that electron could be found near one atom, near the other atom, or in between the two. | 18 | 17 |
CMV: Israel is a settler-colonial state | The gradual accumulation of Jewish settlements within the Palestinian West Bank areas aims to slowly but surely assemble a Israeli/Jewish majority before completely annexing the area over time. The reason it hasn't happened already is because if it had, the Arabs would wield significant influence over the Israeli state and it in essence would stop being a "Jewish", albeit secular, state. It's easier to keep the Arab/Palestinian population there subject to Israeli military control without actually having any say or as many rights as the Jewish people living in the exact same area. Looking at it this way, you can even interpret the modern context of the West Bank (I understand Israel proper doesn't resemble this style of system, as I'm sure people would have pointed out - I know Arabs are equal within Israel proper) as similar to that of the apartheid system in South Africa pre-1994.
Indeed, the entire creation of Israel was fundamentally based on fast paced Jewish immigration to the country for decades before, in an attempt to establish Zionism based on what was perceived to be the 'home of the Jews', and it would inevitably happen in a settler colonial-like manner. One only needs to look for the [Palestine Jewish Colonization Association](https://en.wikipedia.org/wiki/Palestine_Jewish_Colonization_Association), founded in 1924, and the [Jewish Colonial Trust](https://en.wikipedia.org/wiki/Bank_Leumi), in a historical context to see what was planned. As time progressed and more Jews came in decade by decade, ultimately the Arabs were no longer the majority. The 1948 Palestinian exodus, where 700,000 Palestinians were forced from their homes, is a crucial example in support of this idea.
Jewish settlements were slowly being established within Mandatory Palestine, and a [Jewish Settlement Police](https://en.wikipedia.org/wiki/Jewish_Settlement_Police) was even set up, before Israel conquered the whole nation. Does this sound familiar? Look at the West Bank today and Netanyahu's recent pledge to annex parts of the Jordan Valley if re-elected.
Edit: A "settler-colonial state" can be defined as a 'type of colonialism that functions through the replacement of indigenous populations with an invasive settler society that, over time, develops a distinctive identity and sovereignty.'
What Israel is doing now, although clearly now it's a modern context and would clearly be less violent I understand that [not involving slaughter], has the same objective as that did of the Muslims to them thousands of years ago before on the same land. However, seeing as the Palestinians had now had been there for such a very very long time, they can now be defined to an extent as "indigenous" or at least well settled there as a society.
The creation of the United States and Canada certainly came about that way, and their modern creations may be described as products of a former settler-colonial state. The difference in Israel is that it's still happening within the West Bank areas and hence why Israel can still definitely hold that title, whereas in the North American states it has now ended. | It would probably help the discussion if you gave a precise definition of what you consider a “settler-colonial state”.
Some of the definitions I’ve seen are so broad that almost every country in the world could be described as one. | 10 | 26 |
ELI5: How exactly does sound travel through walls? | Or any other solid, for that matter? | Sound is merely pressure waves of molecules bumping into other molecules, transferring energy. When the wave hits a solid object, some of the energy is transferred to the wall, allowing the sound to propagate through it. Then the molecules making up the wall push on the air molecules of the other side, allowing you to hear through the wall. Some energy is lost or reflected in the transitions, thus why the sound is muffled. And some frequencies transition better than others. | 21 | 28 |
CMV: Rule of Law in the US is coming to an end | I make this CMV in light of the death of RBG.
My view is that the Rule of Law, as we understand it, is coming to an end. With a blatantly ideological SCOTUS, hundreds of young Federalist society judges filling the judiciary, and an attorney general whose view of the law is a weapon to be wielded against anyone the Republicans dislike, I do not expect the Rule of Law as we understand it to survive in the US.
The Republican party is attacking the Rule of Law itself with the excesses of the Trump administration. So far as I can see, the new Rule of “Law” is going to be arbitrary, capricious, and authoritarian to the benefit of right-wing ideology.
Would a Biden election change my view? No. The reforms necessary to maintain the Rule of Law will be successfully blocked by conservatives until they come into power, either by maintaining control of the Senate or motivated decisions made by the conservative SCOTUS.
Some miscellania:
I will be using the following definition for “Rule of Law”
>An independent, impartial judiciary; the presumption of innocence; the right to a fair and public trial without undue delay; a rational and proportionate approach to punishment; a strong and independent legal profession; strict protection of confidential communications between lawyer and client; equality of all before the law; these are all fundamental principles of the Rule of Law. Accordingly, arbitrary arrests; secret trials; indefinite detention without trial; cruel or degrading treatment or punishment; intimidation or corruption in the electoral process, are all unacceptable.
Any comment along the lines of “The Dems are doing this too” or “What about the Democrats” or “Aren’t you biased against Republicans?” are not convincing to me. Try harder. | Fundamentally both parties will choose judges that Align with their political belief system. Ideally though, the judges should be chosen to be “neutral” in their decision making. This is operational. ALL people will have personal ideas, leanings, etc but a person that things logically should be able to set aside biases and think rationally.
The problem that most people don’t get is that many issues are ideologically charged and this ideology needs to be addressed bc it is fundamental to the decision making process. Meaning that some issues cannot be separated from their ideological base.
This is not a loss of “Rule of Law” but a difference in foundational belief systems. | 42 | 28 |
How much attention does the nature of suffering receive in philosophy? | I've recently been exposed to William MacAskill's work about effective altruism, see this conversation [here](https://www.youtube.com/watch?v=Qslo4-DpzPs), for example. Of which the guiding question seems to be, how can we do the most good, in terms of the alleviating of suffering, in the most effective and efficient way possible? Of which a dominant answer for MacAskill is via donation to effective charities such as the [Against Malaria Foudnation](https://www.againstmalaria.com/), whereby $2 USD, can buy 1 malaria net, and ~1500 nets is apparently equivalent to the saving of 1 life.
What i'm curious to know is how much attention suffering and the assessment of it among different people or populations has played in philosophy. Some questions i'm hoping some philosophers have attempted to answer:
1) What is the nature of suffering?
2) What is the most amount of suffering any human or non-human animal can endure?
3) How does suffering compare across individuals? Such as that of a child birth versus being shot.
I'm not sure 3 is entirely a philosophical question, but it certainly relies heavily on 1.
One reason why i'm bringing up these questions is that it seems to be an assumption of MacAskill that saving a life is one of the best ways of alleviating suffering, given the attention that he pays towards the Against Malaria Foundation, but i'd rather like to examine this assumption, because it isn't clear to me that that's the case, and that examination starts with the question, what is suffering? So any summary answers, or links to nice introductory articles would be greatly appreciated. | Susan Sontag has a wonderful little book called “Regarding the Pain of Others.”
Arthur Schopenhauer wrote a book called “The World as Will and Representation” in which he avers that will is unavoidable but will also creates suffering. That’s right. All pessimism all the time.
The Utilitarians (someone mentioned Peter Singer, but much of his ideas come from Bentham and Mill) have worked out a system of ethics based on avoiding suffering.
Viktor Frankl wrote about his experiences in Aushwitz which really becomes a reflection about the relationship between suffering and human meaning.
Buddhist monk and teacher Tich Nacht Hahn has some lovely translations and introductions to the sutras that reveal the spiritual truth that life is suffering, but finds nobility in that truth. | 24 | 46 |
[ATLA] Did each of the four nations only have benders of their respective element? Ex: Were there any earth or water benders living in the Fire Nation legally? | If so, why didn't they aid in the war? Earth benders with allegiance to the Fire Nation would have been very useful in breaching the wall around Ba Sing Se. | Bending is as much genetic as it is spiritual, so some of the nature of bending passing between generations is up for debate. But yes, it seems like benders of one specific type congregate and have bender children of that type within the confines of their nations.
Cross-bender migrations and contact happened before the war, as evidenced by the swamp benders being a long-lost group of waterbenders far from the poles. (and perhaps sandbenders learning airbender techniques to augment their natural earthbending) But it's very probable that 100 years of constant fighting with the fire nation consolidated and segregated the remaining bender population. Especially since the firebenders held themselves to such a supremacist regard, and seemed unwilling to use other benders as allies except in very specific scenarios, often ones where the firebenders are clearly in a superior position. (referencing the way Azula used the Dai Li)
Waterbenders would not have been able to live in the fire nation, since it was accepted knowledge for many decades that the previous airbender avatar was dead, and the next would be born a waterbender. That's why the southern tribe was so brutally attacked and stripped of its benders. And the north was barely strong enough to resist, but it would have come under heavy assault even without Aang's reappearance. | 71 | 87 |
Prof claims first authorship for paper that I wrote 75% of. | Hi everyone,
I was scrolling through the recent posts, and there was this post about getting screwed out of authorship that generated a great deal of discussion. My story is marginally relevant to that post (also on the issue of authorship) but with major differences which I will now elaborate on.
Prof is relatively new to the faculty, and not yet tenured. I'm currently the only graduate student at his lab, and the first PhD student to be under him. One advantage of this situation is that I'm often at the frontline of his aggressive pursuit of new studies, collaborations, and publications, and therefore benefit from active involvement. The disadvantage is that this "active involvement" meant skipping sleep to produce whole drafts of manuscripts within days, running and re-running analyses for all the lab's studies (including undergraduates' projects), and stressing over reviewers' requests for revisions. To provide some context, Prof is not at all handy with data analyses (a huge surprise for me, considering that my field is in the area of quantitative science). I often get emails asking me to analyze data ("Can you analyze this and tell me what you find by tomorrow?), without any specifications of the types of analyses required. My job is to figure out how to frame research questions based on the variables, produce interpretable and interesting findings from the analyses, summarize them, and send them to Prof. Thus far, Prof has provided very little intellectual contribution to any of his projects, an observation that has led to past batches of graduate students leaving the lab and his not-so-pretty reputation in the university.
So one day, after I did the analyses and interpretations for a dataset, Prof told me to submit a draft manuscript to him in 3 days. Incredibly stressful, but I met the deadline. Then Prof just said that he would work on it further before sending it to a collaborator. A few months later, I received an email from Prof asking for edits, and the revised manuscript was attached. The introduction part was written largely by Prof, but the rest of the paper remained exactly, word for word, what I had initially written. I was "informed" (by looking at the list of authors in the manuscript) that I would be third author, and Prof would be first. I'm thankful that I get to be in a publication anyway, but I feel like I'm doing much more work than what the first author has contributed. Sure, Prof provided the resources and came up with the research question (mainly a replication of the collaborator's prior work). However, data interpretation (an unexpected finding) was done by me and the collaborator. I also get the feeling that Prof has been trying to block me out. I have to send him all drafts and revisions, which he then sends to the collaborators, and I'm kept out of the loop until there is work to be done. If my input wasn't needed, I wouldn't have known about the order of authorship until the paper was published.
I'm not here to make accusations and I don't think I'm gonna find trouble for this, but just mildly curious whether this is the way authorships operate. There's another paper that I wrote in its entirety, and now I'm wondering if I would be blocked out of the subsequent processes once I complete my job of producing the manuscript.
| Etiquette on authorship is very field-dependent. Some fields just use alphabetical ordering of authors as standard. However, in the majority of science fields, first author is the guy who did the majority of the work (usually grad or post-grad), and final and corresponding author is the guy who raised the majority of the money to do the work and/or who supervised the work.
So it sounds like you are being screwed here, but it also sounds like this is a small portion of a large pattern of being screwed rather than an isolated incident of screwing. | 36 | 43 |
ELI5: What is the point of XML? | I have a great understanding of database systems, HTML and CSS but I after reading for hours and even watching videos I cant see why anyone would ever use this. It does not seem an appropriate or efficient way to deal with data. | XML is a well defined, general purpose, data transfer language that's designed to facilitate the transfer of data from one system to another in a standard way. Before XML was a thing, every program had its own protocol so you'd have to write new parsers for data import or interchange between every system. XML is basically HTML intended to be used for machine-readable data.
It's not intended to be efficient from a CPU or space perspective. It's intended to be a single, easy to work with standard so that all systems can transfer data between each other using a standard XML parser to interpret the data - it's efficient in terms of *programmer time*.
Whether it's actually effective at this is a matter of debate. | 11 | 15 |
I believe any argument for or against the existence of a god or deity based on scientific knowledge is irrelevant. CMV | My argument is as follows: a. The whole point of a God or Deity is that they are supernatural. b. Science deals with learning things about the natural world. c. Therefore, scientific knowledge of the natural world cannot be applied to argument in a debate.
Of course, my argument does not apply to any belief that relies on a God who, in order to exist or be consistent with itself, *must* have done something that has been proven wrong scientifically (for example, if the Christian god *must* have created the world in six literal days for him to exist (which I disagree with, although that's another CMV entirely), then the Christian god simply does not exist based on scientific knowledge).
I should make it clear, I'm not entirely sure of my own religious beliefs. I put myself around a 5 on Dawkin's scale from The God Delusion. However, the growing reliance on scientific knowledge from both sides of the debate is something I'm starting to get annoyed with. Many religious people (namely Christians Muslims and Jews) use creationist arguments to debunk evolution and therefore prove God real. On the other hand, we have a lot of arguments against religion that are based on scientific knowledge themselves. What I want, in the long run, is for everyone to just be objective and seek the truth, and that means stopping arguments based on false premises (from either side of the debate). | If God does not have a measurable effect on the world, then in what sense does He exist at all? If he does have an effect, why preclude efforts to measure and study that effect in order to understand Him better? | 29 | 23 |
ELI5 What stops the bacteria that rot corpses from eating living things? | Biologist here
Our immune system keeps most of them in check.
Most of the bacteria that consume a corpse are the bacteria that live and work inside of the body. Once the immune system dies with the body, they are able to explode in growth, consuming the tissue around them to propagate | 115 | 52 |
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ELI5: How Credit Scores Are Determined | I get that a 900 is fantastic and a 200 is awful, but what do these numbers mean and how does whoever comes up with them come up with them?
**Like I'm Five**
***FIVE*** | The short answer is only the credit bureaus know exactly, but there's a few things that everyone knows play a role:
*Length of credit history - longer is better
*Payment history - no reported late payments, no reported defaults/delinquencies
*Amount of available credit and ratio of used/unused credit - large amounts of available credit with a low usage ratio is best
*Number of open lines - more are better, as long as they are paid on time | 26 | 114 |
ELI5: How do chess computers work? | There are two main components, a static position evaluator and a search tree.
The position evaluator looks at the current position, and gives it a score, mostly based on material but includes other factors as well.
The computer then builds of a tree of all possible moves for say, the next four moves. It scores all the resulting positions, and decides which move leads to the best outcome.
There is a lot more to it, but that is the core of what a chess computer is doing. And since it is computer, it can look at millions of positions before deciding its next move. | 18 | 18 |
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Why does smoke stun bees? | Why do bee keepers use smoke to calm bees down? Is there some sort of chemical process involved? How does the smoke affect the bees? | Smoke masks alarm pheromones (which include various chemicals, e.g., isopentyl acetate[1]) that are released by guard bees or bees that are injured during a beekeeper's inspection. The smoke creates an opportunity for the beekeeper to open the beehive and work while the colony's defensive response is interrupted. In addition, smoke initiates a feeding response in anticipation of possible hive abandonment due to fire. When a bee consumes honey the bee's abdomen distends, making it difficult to make the necessary flexes to sting. (The latter has always been the primary explanation of the smoker's effect, since this behavior of bees is easily observable.)
Don't know if im allowed to post what i found from googling as im not a expert but there ya go. from wiki. | 61 | 38 |
eli5: Why did the life expectancy for people with down syndrome increase from 25 years in 1980 to 60 years today? | I read that it was largely due to the end of the inhumane practice of institutionalizing people with Down syndrome but i don’t really understand what this means. | A lot of people with Down Syndrome have a number of other health problems besides the cognitive issues that people mainly notice. For example many have a heart problem, atrioventricular septal defect. If untreated or poorly treated, this can lead to a very early death. There are a number of other health problems they can have. With better health care, they will live a lot longer. They’re getting better health care now than they used to. They’ve stopped the institutionalizing so much and now often mainstream them as kids, which has had great results. | 130 | 141 |
ELI5: How do equations explain the universe around us? | Long story short; we have equations for describing the universe because we can measure so many aspects of the universe.
Imagine you're going to the shop to get a pie or something. The shop is about one kilometer away (and you know that because someone measured it and put it on a map) and it takes you ten minutes to get there (and you know that because you checked your watch). That means it took you 600 seconds to travel 1000 meters. Work the math through and you get 10 meters every 6 seconds, 5 meters every 3 seconds or five thirds of a meter every second.
Hopefully that all makes intuitive sense. If you look back through that paragraph you'll see we took a measure of distance and divided it by a measure of time to get a measure of speed. In physics we measure speed in straight lines and call it velocity. We can describe the relationship like this: **velocity = distance / time** or **v = d / t**
By taking careful measurements of other observable things we can discover all kinds of similar equations that seem to be pretty accurate descriptions of how things actually happen. We can push weights around to discover the relationship between force, mass and acceleration. We can play with electricity until we discover the relationship between current, voltage and resistance.
The cool thing about these equations is not just that they help us understand relationships between things but we can use them to make predictions about what's going to happen in future. Understanding electricity allows us to plan computers. Understanding projectiles allows us to bomb the enemy. Understanding gravity allows us to plan trips to other planets.
So it's not that equations explain the universe so much as equations are an expression of our understanding of the universe that we've gleaned through careful observation and experiment. | 17 | 38 |
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If the earth is a closed system, then how can water be wasted? MIC | The water available in an aquifer is limited, and rate of replenishment is much less than rate of use for many aquifers (we can pump it out much faster than it can naturally refill) causing them to effectively dry up, leaving no readily accessible water for some communities.
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How can (relatively) slow evolving human immune systems keep up with very fast evolving bacteria? | If the generation length ratio of bacteria to humans is something like 20 minutes:20 years, why can't bacteria just outrun the immune system recognition mechanisms, or destruction mechanisms? | There are two reasons for this, related to the innate and adaptive immune system.
First of all, the innate immune system has, throughout evolution, been tailored to recognise invariant structures on the surface of bacteria. The reason these structures are invariant is because they are essential to the bacteria's survival, e.g. certain peptidoglycans. This means bacteria can be recognised on the basis of their defining characteristics. However, not all the bacterium's characteristics are predefined, and some bacteria can camouflage these invariant ones, which brings us to our next point.
The second reason has to do with that our immune system is not pre-defined, and goes down deeper than our "standard" genome. B- and T-cells are able to randomly combine certain pieces of DNA in our genome, in a process known as VDJ recombination. This essentially yields a "randomised" gene, which codes for an equally random protein. These proteins essentially recognise every possible structure that there is to be found. To prevent our immune system from attacking structures in our own body, there is a round of selection that kills cells that recognise those endogenous structures. This way, 'foreign' structures (i.e., whatever isn't supposed to be there) are recognised for elimination from the human body.
You might wonder, how come we don't instantly fight off any infection then? The answer is simple; because usually, only one or very few cells exist that recognise the structure present on the bacterium/virus. When an infection is detected, these cells are stimulated to divide and proliferate, a process which obviously takes time.
Hence, while bacteria may evolve quickly during a few generations, we can adapt quickly *within* a generation.
Obviously this is a boiled down version of the truth, and there are many more intricacies which finetune our immune response to a given pathogen. But this should give you an idea of an answer to your question. Feel free to ask on though!
Edit: clarity and some more info
Edit 2: spelling. | 43 | 32 |
[Project Zomboid, other apocalypse media] In an event like a zombie outbreak, what would be the reasoning behind cutting the phone lines to a quarantine area? | To prevent pleas for help. If there are no outgoing calls, the government can tell everyone everything is being handled.
But if the lines are working and you get a tearful call from your daughter trapped in the zone, you're going to do everything in your power to break through the quarantine to get her, regardless of what the government says. | 55 | 44 |
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ELI5: What’s the science behind “sea legs?” | There are several theories about the specific effect but its not important enough to research properly. On a more general level, the human body likes to maintain a lot of "normal" conditions, because it functions best when it has some standard patterns to follow. For example, jet lag is the body clock's standard pattern being out of sync with the body clocks of the people in your new location and it takes a long time to adjust it because your own body clock is trying to reach your internalised "normal" pattern.
Our balance and a few other motion senses are regulated in a similar way. The orientation of our head is measured using liquid components in our ears for example and this is used to know whether we're vertical or laying down. It would be annoying for the brain if it was constantly taking in and processing new information about your position due to the bobbing of a boat, so after a while it adds some compensatory information which makes it feel like you're standing still even though you're bobbing. It compensates by adding reverse bobbing sensations. So when you step on land and the bobbing sensations disappear, the reverse bobbing sensations are still there because your brain takes some time to adjust to being on stationary land again and during this time it feels like you're bobbing still. | 12 | 17 |
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Is there any evolutionary benefits other than sexual selection in having blue or green eyes instead of brown? | And other than Caucasian is there any examples known other than those of mixed race with Caucasian that have had the mutation that causes blue or green eyes? | Like skin tone, lighter eye color is simply a reflection of lower pigmentation (less melanin). As with many genes, if those genes that influence eye color can mutate to less active forms without dicouraging the survival of a given organism, they may continue to mutate to less and less active forms. This means that if higher pigmentation isn't all that advantageous to some animal, lower pigmentation may result.
There may be a selective factor at work, however: lighter skin tone was favored for north-dwelling human ancestors because it generates more vitamin D (which, closer to the equator, would have been supplied by the abundant sunlight). Because some of the genes that govern skin and eye pigmentation overlap, lighter eye color may have been coincident with lighter skin color. | 32 | 81 |
ELI5: what is primordial soup? | It's an idea that, once, many many years ago - before there was life - there were pools and lakes and maybe oceans of water that were full of minerals and salts and rich in complex chemicals. The idea is that, through various means, these chemicals, in a soup, interacted with each other to create proto-life. We THINK something like thins MIGHT have been involved in the beginning of life as we know it (abiogenesis) but it's just one idea among many.
(or did you want an actual breakdown of ingredients?) | 33 | 67 |
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CMV: the age of adulthood should be the same for all rights and responsibilities, and all restrictions thereof | It is my view that the inconsistency in the way we treat the age of adulthood (for the purposes of administering people's rights and responsibilities) is causing undue harm in society, both due to collateral damage of allowing people too young to engage in risky activities, and due to the pervasive acceptance of blatantly irrational and inconsistent policy distracting us from the real issues while we get bogged down in debating different age restrictions for different activities.
There is a massive 10-year period (ages 15-25, approximately) during which a person in the United States is considered somewhere in between a totally dependent and incompetent (legally speaking) minor, and a fully competent and independent adult.
I'm interested in changing my view particularly because of the gun control debate. Raising the age requirement to purchase a gun to at least age 21 universally at the federal level seems like one of the most common-sense and uncontroversial reforms we could potentially make. However, considering this policy makes me uneasy in relation to our other age-related policies.
Guns aren't the only thing that's potentially dangerous. A car can harm and kill a lot of people too (remember Waukesha? 6 dead and over 60 injured, by an attack using an SUV at a Christmas parade). And that's just one of the intentional attacks; fatal traffic accidents remain among the leading causes of death in the US - higher than gun homicides in most years. And young drivers are disproportionately involved in traffic accidents. Yet we let kids operate these killing-machines-on-wheels provisionally with a permit at age 15, and fully licensed unrestricted at 16. Why?
The ballot box can be harmful too. Your vote matters; it can be the difference between economic prosperity and poverty for millions of people, between expanding civil rights and restricting them, between peace and chaos. In the extreme case, your vote can have consequences even more harmful than any single weapon, if your vote enables the rise of authoritarian tyranny and oppression.
We let people vote at 18, along with the majority of other "adult" rights and responsibilities - right to do what you want with your body (tattoos, donate blood, get married), responsibility to do jury duty, draft eligibility (for males), ability to be legally bound by contracts, etc.
However, despite holding that people are not competent do do all these things until 18, in many states people are considered legally competent adults for the purposes of consenting to sex at age 16 or 17. How can I consent to share my body with another person in sex if I cannot consent to be bound by a legal contract, or to pledge to use body to serve my country in the military?
And despite being considered a full legal adult in most ways at age 18, especially in terms of your responsibilities to society (jury duty, the draft, taxes, etc.), some rights are still restricted for several more years. No drugs or alcohol until 21. Potentially no right to keep and bear arms. You can't rent a car or hotel room in some places until age 25.
If anything, age 25 is the most "rational" place to set the age of adulthood, because [neuroscience research has found](https://www.inverse.com/article/33753-brain-changes-health-25-quarter-life-crisis-neurology) that the prefrontal cortex, the part of the brain responsible for executive decision making (risk management) is not fully developed until 25. That's a big part of why young people are so heavily disproportionately involved in traffic accidents, in violent crimes, and other incidents involving risky behavior.
I'm on the fence whether I would actually support fully raising the age for everything to 25, but still...if we don't believe a person is mature enough to wield a firearm or consume alcohol responsibly until age 21+...why the hell would we let them get behind the wheel of a car or vote? It doesn't make sense to me that these age limits are different. Driving and voting are just as potentially harmful to society as drinking or owning a gun, so it feels weird to talk \*only\* about raising the age requirement to buy a gun and not any of these other potentially deleterious activities.
I just wish there was more consistency. It's really tiring and distracting having to debate and defend these issues with people on a case by case basis. If we just agreed "okay, nobody is considered a fully responsible adult until age x" and all rights and responsibilities kick in at that age, and not a day before or after, we would be better off. CMV | Why is consistency an inherent good? Sure cars are dangerous but that's hardly enough similarity to say they must be treated the same as guns, just because guns are also dangerous. These things should be treated differently because they are different. | 307 | 1,030 |
ELI5 why is 'Head and Shoulders' shampoo "For men"? | Just marketing, or is there more to it? | For most 'drugstore' brands of toiletries like shampoo, soap, and deoderant, the only significant differences between the mens and womens versions of products are:
Scent: since most men don't want to smell like tahitian vanilla and most women don't want to smell like whatever-it-is axe smells like
Price: you can see this most with razors. mens products are generally priced lower than womens for the same volume
Color: most noticeable in the packaging, but occasionally the product itself is colored
Once you get into the high-end 'salon' products, there can be true formulary differences. | 31 | 30 |
ELI5: Why do you hear about police breaking the law (like strangling the guy in Tennessee) and they just get fired rather than arrested and charged? | It seems like this happens a lot. If a member of the public behaved like that we'd get thrown in jail for a long time.
A police office does it and they simply get unemployment. Is there a justification for this? | Police are afforded a significant amount of individual discretion in deciding what is an appropriate or reasonable level of force to use. It's a judgment call in the situation; occasionally they get it wrong. If they knew there was a high likelihood of being charged with a crime themselves there could be situations where police do not use the necessary force required to keep themselves and the public safe.
For that reason, cases of police brutality and the like are more often handled as an employment matter (not fit for service) rather than a criminal matter (not fit for society). | 234 | 567 |
It seems like it's possible for consent in sex to be violated without anyone being morally to blame. Does anyone have any reading on this? | Fair warning: This post discusses the potential for sexual assault, though in as dry and non-graphic a tone as I can manage.
So I've kinda had this idea bouncing around my head for a long while, so I came here to see if anybody's ever thought this over before. I've been looking but I can't find anything from any philosophers. I'd love to hear from folks who have an interest in sex ethics or who might have related reading.
I'll write from my own perspective, then zoom out and ask questions about the general principle of the thing.
So ethical sex requires informed consent (at least by the moral framework I subscribe to). Practically speaking, that means I need to be as sure as reasonably possible that my partner actually understands what I want from them and is willing without coercion to participate. In college, I was taught to seek an "enthusiastic yes". Not just a sigh and an annoyed nod or a drunken "yeah okay", but active, engaged consent both verbally and in body language.
That seems like a good starting point to avoid a lot of potential for communication errors, but it got me thinking: What if I do all that, but she (as I'm a heterosexual man) was signaling her lack of interest in a way that I'm not familiar with? Am I to blame, even if it was communication that I couldn't reasonably be expected to understand? At that point I've just committed rape--as the definition we use for rape revolves around the consent of the one raped. If a person does not consent to sex, then they have been raped. And rape by definition requires a rapist, doesn't it?
Further, what if somebody does absolutely everything they reasonably can to ensure that their sex partner gives informed consent. They speak the same language, are both familiar with the same type of body language, they get to know one another very well before sex, all of that. It could still be rape if one of them feels coerced and doesn't show it for whatever reason.
What if somebody had autism and couldn't read body language and relied on the actual words somebody said and the fact that they were cooperating? What if somebody is vacationing in another country and doesn't understand the slightly different body language? What if peer pressure made somebody pretend they wanted it just to "get it over with" and lose their virginity or something to avoid social repercussions from their social circle? Or what if the victim was never taught how to communicate a lack of consent, and didn't know how to signal it in the ways that a partner would reasonably pick up on it? There are a great many different situations where this applies.
While I'm thinking on it, it's even possible for two people to be raped by one another, with both feeling coerced and neither picking up on it from the other party. What then?
Anyway, I guess I want to talk this over with folks. It seems like this is a major problem with the way we frame conversations about consent. | I think what you are interested in is the conditions for valid consent and there is a lot of discussion of these in the medical literature along terms that are similar to the concerns you raise here.
So the requirements for consent to be valid are rationality, understanding and freedom. Proponents of consent as a central concept in the doctor patient relationship acknowledge the potential difficulties but highlight solutions and the responsibility of the person asking for consent to be aware of these pitfalls and take steps to avoid them. So, for example, a doctor faced with a patient who is a recent immigrant and appears to be shy and introverted should also consider the possibility that language barriers are causing a problem with understanding which affects the validity of consent. Consent and autonomy are the dominant narrative in medical ethics so there are loads of discussions around these issues. Other philosophers, Onora O’Neill comes to mind here, think these problems with consent are reasons to do away with an over reliance on the concept and recent research the discussion on rights.
Specifically on the literature on rape a few authors liken rape to an act of violence expressed through sexual means, so this kind of approach makes one’s motives crucial. Genuine misunderstandings would not have the same moral status than deliberate acts of violence through consent. But this is just one approach. | 53 | 123 |
Can we "fix" our genome so that we can synthesize Vitamin C? | So apparently humans (as well as other apes and monkeys) [can't synthesize Vitamin C](http://en.wikipedia.org/wiki/L-gulonolactone_oxidase) which is why we get scurvy without proper nutrition. I don't know what we can and can't do these days with genetics: Can we just repair the gene in embryos and begin birthing a race of assuredly scurvy-free humans? Any idea on what, if anything, else this would affect in those people? | i guess we *could* implement the biochemical pathway, but a much more important issue is the regulation of that pathway. it isn't just being able to, it is about making enough and not too much. also, there are dozens of other biochemical pathways that can be impacted if we introduce this new ability into people (assuming that we even could). it would take a lot of trial and error and even if they started right now, i don't think we could get it working within the next 50 years. | 10 | 25 |
If scientists do not read Newton and mathematicians do not read Euclid, then why do philosophers read Aristotle? | Note: obviously this question does not concern those three specific men. | Learning the history of science/maths may be rewarding but they're not required for a scientist or mathematician to do their work. They don't need to know who's Newton developed his theories in order to use them.
In philosophy, however, history is used to track the meaning of a word or the development of an idea. Philosophers refer to the works of previous philosophers. And you sometime might want to read the original text "unfiltered" by any secondary account of their work and form your own study.
Unlike maths or science, which are generally taken to be universal, the philosophical literature is a product of its time and place in history.
If you want to discuss a concept (say "virtue") with another philosopher you have to have to know the context and the background. | 36 | 15 |
How do we know that the laws of physics are constant? | Almost every physical law has breakdown points. Two common ones are inside black holes and during/before the big bang.
A lot of things we know because we can look out in the universe and we can apply our earth-laws to anything we want out there and we can still accurately predict what's happening.
A law is just a relationship that can be used to make predictions. As long as we keep testing predictions and we're spot on - then the law is constant. | 12 | 26 |
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ELI5: How are skyscrapers in crowded cities like New York built in such a tight space? | Construction in crowded cities seems to happen with minimal disruption to traffic or neighboring buildings. How are cities able to build these huge skyscrapers without spilling over onto nearby streets and taking up a lot of space with equipment and materials? | Construction management is it's own field.
Usually an adjacent area is blocked off for staging, but as you said, as minimal as possible.
Remember, it's not usually worth it for anyone, for any project, to bring material and equipment that won't be used for a while, and there is only so much that workers can do at a time, so right there, it's just a truck and small staging space at a time. Easy. Skyscrapers like any project, are built one day at a time, so have materials/eqp. For the one day -at a time.
Further,
In this case, it basically comes down to that for the first couple of stories, they only bring as needed, so that it doesn't take up too much space, then after that, the have the constructed lower stories themselves to store equipment etc.
Finally, very large things that would indeed be brought in at night, or have areas blocked off, but as soon as on the site, open the space back up.
The cranes are usually only a few feet wide, and are either on top or more commonly, attached to the side of the building itself, so it's footprint is minimal
| 19 | 18 |
[LOTR] What extra power does the One Ring by itself grant Sauron? | This is a bit basic and has probably been answered before, but it's one thing I never understood in LOTR. The power of the ring comes from the significant portion of himself Sauron poured into it, right? And the reason he created the ring was to rule over the other rings, no? So aside from ruling over the other rings, how did creating the ring benefit Sauron? | The One serves two primary purposes - controlling the other Rings, and bending minds to the bearer's will.
>*Now the Elves made many rings; but secretly Sauron made One Ring to rule all the others, and their power was bound up with it, to be subject wholly to it and to last only so long as it too should last. And much of the strength and will of Sauron passed into that One Ring; for the power of the Elven-rings was very great, and that which should govern them must be a thing of surpassing potency; and Sauron forged it in the Mountain of Fire in the Land of Shadow. And while he wore the One Ring he could perceive all the things that were done by means of the lesser rings, and he could see and govern the very thoughts of those that wore them.*
**-The Silmarillion: Of the Rings of Power and the Third Age** | 75 | 121 |
[MONSTERS INC.] How do the monsters breed? Are they different species altogether, or variants of the same species, like dogs? Do they have to get with someone of the same 'type'? | In Monsters University, Squishy and his mother are both the same 'variant' of monster, and we presume the father is too, leading us to believe only two monsters of the same 'type' can breed. What if Mike and Celia were to have children? Would all children look the same? Would they be a mix of the two parents and create a new 'type'?
Secondly, do the monsters even have sexes? They're referred to with at least two pronouns ('he' and 'she'), but as far as I'm aware have no defining sexual characteristics. | Potentially like Pokemon. In Pokemon, creatures of different species are capable of breeding as long as they're within the same "egg group". Monsters seem like they belong to one "species" - monster, but because of differences in their morphology it's likely that there are certain groups that are physically capable of reproducing and having sex with each other.
Ex. Mike and Celia are most likely capable of having sex with each other since they're romantically entwined.
It's not definite that all can have sex with each other though, and with such wildly different bodies, it's unlikely that say Sully and Roz could fuck.
The babies would probably take after both parents. Mike and Celia's baby would be one-eyed, maybe have horns, maybe have snakes, could be tall, could be short, maybe pink, maybe green. | 15 | 20 |
[Futurama] How did palm trees get chosen as the replacement as X-Mas trees after pine trees went the way of the poodle and modesty? | Climate change and abundance.
As the climate regions shifted the palm tree became more suited for much of America. Following this palm trees became much cheaper to farm and cities also began planting them in public places instead of the mor expensive types. So with palm tree proliferation and then the subseuent world wars/invasions and such over the 1,000 years, what was originally grasped from past culture to continue on the tradition was the common and state sanctioned palm tree.
...yea. yep, that makes enough sense. there ya go. | 29 | 40 |
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ELI5: why is it so easy to fall asleep on your couch even with desperately trying to stay awake, but after dragging yourself to bed, you find yourself wide awake and unable to get back to sleep? | I think this is a psychology rather than biology question.
The answer will vary from person to person but broadly it's likely to be that when you're on your sofa you're in your relaxation frame of mind so you can go to sleep but when you start your bed routine you start thinking about plans for the next day so you a/ get your brain working and b/ start worrying about how much sleep you need so can't relax.
It's basically a 'sleep hygiene' issue, meaning your bed routine isn't helpful. | 273 | 622 |
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[Evangelion] Why is Tokyo-3 built directly above the Geofront and Terminal Dogma? | It's not like the citizens had to live on the giant armour plates to make them more effective.
Since the residents of Tokyo-3 would be much safer if they weren't in the direct path of the Angels, why isn't the city located a short distance away from the Geofront? | It serves several functions:
1. It allows NERV employees and their families to live close to their base of operation. Similar to how military bases often have neighborhoods very close to them.
2. It provides camouflage for NERV's shadier practices. Its much harder to spy on or infiltrate a location when its hidden underneath a city. Also, in the event they should come under attack (like in End of Eva), the attacking army would have to weigh the risk of going through civilians.
3. Distracts the Angels. While they are busy stomping through buildings and dealing with the defense weaponry NERV can scramble the EVAs.
4. It helps distract people from the true intention of the Angels. Public record states that Angels are draw to humans to kill them, making a city an ideal place to corral and ambush them. So long as people are focused on that, they won't snoop around and find Lillith. | 18 | 27 |
ELI5 how mirrors seem to be the color of what they are reflecting while also looking silver. | I have been wondering this since I was a child and it’s never been explained in a way I can understand.
I’m looking at my bathroom mirror and it looks silver. But how is that possible because it’s reflecting whatever is in front of it?
So when I look at the reflection of the towel in the mirror i see blue, when I see the reflection of the wall I see white, when I see the reflection of the shower curtain I see the color of the shower curtain. But when I look at the mirror as a whole it seems silver?
I think I have read that mirrors have silver backings which makes sense why I see silver. But I don’t understand how it’s possible to see the exact reflection of my bathroom but it’s also silver? | "Looking silver" is what we call surfaces that reflect their surroundings. It's not actually a color. So "seeming to be the color of what they're reflecting" and "looking silver" are one and the same thing, just different ways of describing the same appearance.
If you put a silver object in a uniformly illuminated room with blank walls it wouldn't "look silver", it would look like one uniform color. But that's a really contrived setup that "never" occurs in our day-to-day experience so we don't associate that with "looking silver." | 65 | 76 |
CMV: College should be free for at least 2, maybe 4, years, like high school. | I've made a few generalizations below, of course there are some people who dropped out of high school and are millionaires, and some people that graduated from medical school and have no job. However all of you know just as well as I do, that these generalizations are mostly true. (just don't even bother arguing this part, don't post if you're going to say they're not)
Sure, you can possibly make a living with just a high school degree. But it'll be absolute crap and the best most of them can hope for is to live in a small, run-down apartment in the highest crime rate neighborhood in the entire city. You might even be lucky to live in the projects.
Even if you get a basic 2 year degree, if you get an almost/full time job, you could probably buy a small house in a suburb or rural area. It might not be nice, but you could probably own it and not live in fear of the crime outside your door.
It's a significant step up, and even in the US it should be considered a basic right in the same way public high school education is.
Note that this isn't coming from someone who's butthurt that they don't have money to pay for college, I've been put through it with absolutely no debt thanks to my very generous parents. I just think it would improve just about every aspect of society in every way.
Edit: I thought of another reason for it. When I was in high school, the kids that didn't care about graduating mostly did it because they knew they couldn't pay for college even if they did end up graduating. If you give them another 2 years to look forward to, which ends up in them getting a somewhat reasonable job, they might actually try to complete high school without getting into serious trouble. | First, it is important to understand selection bias here. Part of the reason people with degrees do better than those without degrees is because those who were more likely to do better regardless will usually choose to go to college.
However, your view seems to give a reason to go to college if possible, but not why it should be free. Understand that nothing is actually "free", what you are suggesting is merely shifting the cost from young people to those paying taxes.
One could argue that young people, because they have more years left, will have far greater future earning potential than most current taxpayers. In other words, you are shifting the cost of college from an 18 year old with over 40 years of employment ahead of them to someone 61 and may have only 4 years remaining to earn for retirement.
Under our current system, people are loaned money for college to be paid by their own future earnings. Loans are extensive and easy to get, but they do have to be paid back by the borrower. They are also proportional to the education you receive, so paying back a 2 year degree from a community college is a fraction of the cost of 4-5 years at an expensive private school.
Now, we could discuss changes in how much loan money a person receive and how the repayment structure should look, but doing it this way is obviously more fair than what you are suggesting. | 19 | 30 |
Does the expansion of space apply at all scales? | As in, if space itself is increasing the distance between galaxies, is there also a very small increase in the distance between atoms, subatomic particles, quarks, etc.? | No, the distance between atoms is not increasing because of the expansion of the universe. In fact, no two objects on the scale smaller than a gravitationally bound group of galaxies are increasing in distance because of the expansion of the universe. Expansion only happens between galaxy groups. This may seem weird, but it is the nature of spacetime. Expansion can be thought of as an inherent property of spacetime when not much mass is around. Some sources like to say that gravity inside a galaxy group overpowers metric expansion, but this is a little misleading. Gravity is just a description of how spacetime acts near masses, and metric expansion is a description of how spacetime acts far from masses. Therefore, traditional attractive gravity and metric expansion are really both versions of the same thing: spacetime. So a better way to say it would be that spacetime in a galaxy group acts in the traditional attractive way because there is enough mass around, but outside galaxy groups, spacetime acts according to metric expansion. | 13 | 25 |
ELI5:Who contracts a groups like Blackwater and how exactly do they work comparing to armies belonging to countries? | Wow thank you all for providing good explanations | Companies like Blackwater are hired by private individuals and companies. For example, say you've got a government contract to provide hot meals for the bases in the middle east. You have to get the supplies and food from transportation hubs like airports through and into military bases.
Unfortunately the roads are filled with people who disagree with the military being there in the first place. And since you're supporting the military, you must be as bad as them.
So these people attack your supply chains in an effort to disrupt the military. You're not military, so you can't call in an air strike or get a company of soldiers to protect your trucks. Instead civilians with certain skills will take a big chunk of your profits in exchange for protecting your assets. Those assets might be equipment, translators, diplomats, CEOs and VIPs, information or medicine. And since those skilled individuals are not military, they're not liable under things like the UCMJ, rules of engagement, SOPs or other red tape and bureaucracy.
Obviously this is simplified a lot, as it's not really protecting taco trucks headed from the green zone to Basra, but you get the idea hopefully. | 19 | 38 |
Is Wittgenstein's concept of family ressemblance still considered valid | Hi!
I'm a doctoral student in archaeology, and I'm currently preparing a thesis on a certain category of objects that lacks a precise definition in the literature. This means that when people find the objets in excavation, they sometimes call them "X" and other times call them something different. Some authors have tried to propose definitions, but none have really been taken up by scholars.
As a result, the first thing that people ask my when I tell them about my topic is "How do you define it?". My supervisor also wants me to define it. But it not only seems very difficult to me to give an exact definition, and especially one that will include all the objects and contexts that would be interesting to study while excluding ones that wouldn't be. So I began searching in the philosophy of science for some way to not use a traditional definition of my category.
I came across Wittgenstein concept of "family ressemblance", which seems to be perfect for what I have in mind: a category in which not all members of that category share every trait, but all share some traits. I'm worried, however, that in terms of philosophy this theory may have been strongly critiqued, or improved upon. In the fifty or so years since Wittgenstein wrote about it, how has family ressemblance been seen by philosophers?
Cheers | Family resemblance as an approach to definition is still very common and respectable both inside and outside of philosophy. Notably, in religious studies, it's a very popular way of approaching the problem of defining the term "religion." Certain scholars still defend essentialist definitions, but what you're trying to do is not novel at all. That this could be a useful approach for some concepts is not all that controversial. What is more likely to be criticized are specific applications of the theory. For example, Bernard Suits criticized Wittgenstein's analysis of games as a family resemblance concept in his book *The Grasshopper: Games, Life and Utopia*, but the definition of "game-playing" which Suits proposes ("a voluntary attempt to overcome unnecessary obstacles") has been criticized itself; it's not as if there is a consensus that anyone has "refuted" Wittgenstein on this point. So, it would still be perfectly respectable to try to apply Wittgenstein's idea to various concepts. Whether those applications actually work in practice is better decided by the people in the specific field in question (e.g., ludology, religious studies, archaeology, etc.). | 12 | 17 |
ELI5: Why does the body still feel like it’s moving when in bed after going on a boat or amusement park ride during the day? | Is it something to do with the ears? | There are several body systems responsible for giving your brain the stimulus that it is moving. The eyes, the cochlea within your ears- even the way your guts sag communicates which way you are moving or which way is up.
Most of these systems give immediate feedback- if you continue to feel the sensation of gradual movement long after a ride stops, it has more to do with your nervous system and your brain.
Your brain has been compensating for forward motion and has "gotten used to it" as a norm for an extended time, and even though the stimulus has stopped, your brain may be stuck in that sort of pattern. Kind of like the way your eyes need time to adjust to light, darkness, and colors. | 202 | 455 |
[Die Hard] Did Hans have a Plan B in case the FBI decided against cutting the electricity? | He knew their standard operating procedures. The only reason the FBI wouldn't have cut the power would have been if they didn't believe it was a terrorist takeover, also known as an A-7 scenario. Hans would have upped the ante and began executing hostages in order to convince them.
If for some reason that didn't work, they had enough C4 to flatten a city block. They could've blown the safe along with the building and slipped out with the bearer bonds in the confusion. | 20 | 28 |
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ELI5: when you look at the ingredient lists of products like shower gel, conditioner etc. there are often several types of alcohol included...what's the difference between these alcohols? | A shower thought of mine haha | An "alcohol" is actually a class of molecules that are related in their molecular structure. The one we drink is called "ethyl alcohol", but there are a lot of different ones. They have different consistencies, odors, abilities to dissolve substances and volatility. So depending on what the manufacturer wants, you add the kind that makes sense. | 2,333 | 5,851 |
Should I pursue a college degree or stop after high school and study programming by myself? | It's just a year left before I graduate in high school and I've been thinking about just not continuing to college for a CS degree and instead just study the essentials in it via my own. Would this decision really affect my chances for a job? If yes, then how much?
I'm planning to get a CS degree to get a job around Game Development. | Yes, it will affect your chances at getting jobs. Regardless of what people on this sub think, a college degree in cs is worth much more than a resume full of self-taught topics and personal projects alone especially when starting out.
It is true there are self tough coders who have great programming jobs now, but it's more true that with a college cs degree you'll have more opportunities starting out and fewer companies will just delete your resume finding no higher education. | 56 | 24 |
What is the difference between genetic mosaics and chimera? | Mosaics and chimeras are animals that have more than one genetically-distinct population of cells. The distinction between these two forms is quite clearly defined, although at times ignored or misused. In mosaics, the genetically different cell types all arise from a single zygote, whereas chimeras originate from more than one zygote. | 18 | 70 |
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A lot of nutritional supplements for someone with a reasonable diet have questionable health benefits. Are there any that have rock solid evidence of benefits?t | Examine.com has a really extensive list of supplements and their supposed benefits with links to studies. It seems the most proven are creatine, vitamin d, fish oil, and magnesium if there's a deficiency. | 10 | 68 |
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ELI5: What makes some clothing materials "warm when wet" (like wool) but others not (cotton)? | In the case of wool and cotton it is the individual strands that make the difference.
Wool is rather none porous (it's just hair) and ends up coating itself with natural oils (from your skin, or if raw, the sheep's) that help repeal water. It is a very curly/crinkly material and this creates many pockets of air that warm up and act as insulation.
Cotton is a porous plant fiber (absorbs oils and water into it internal structure) that is significantly straighter. The straightness of the fiber helps create a smoother fabric that lays against the skin rather than poking into it (not itchy, yea!) but is less effective at creating air pockets for insulation. | 71 | 85 |
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How do we get Vitamin D from the sun? Is it like photosynthesis in any way? | Photosynthesis is a process where photon is captured and its energy transported across a chain of molecules for the purpose of storing the said energy. This process is well-controlled at various steps, and organisms have evolved over the years to use the best spectrum of light available.
In humans the majority of Vitamin D synthesis requires sunlight at one stage, but the UV light just provides the activation energy to convert one isomeric form of provitamin D to another (i.e. there is no active storage of energy). This is a spontaneous process not requiring cellular machinery, and the effect is limited to the substrate and product. | 60 | 108 |
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ELI5: How do video game coders optimize their games to boost fps and stability? | The basic method is they look at how long their code takes to perform each function and look to see if there are more efficient ways to perform that function. If you can do the same action with 5 calculations instead of 10 then you have double the speed of your code. If you can avoid having to read data from a slow hard drive and instead have it available in very fast graphics memory then you can similarly increase the performance of your game. | 52 | 27 |
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[Doctor Strange / Infinity War / MCU] What’s the difference between Doctor Strange’s shields? | Throughout the movies, we see him always casting shields to be used on his hands and there always seems to be a new way of casting them. However, they always yield the same orange-sparkly shield.
What’s the difference between the casting types and shields (other, of course, dramatic effect)? | They may look to same to your mundane eyes, but each one is fine tuned to be the best for the situation as Strange sees it. Better resistances and affinities to certain energy signatures for example. | 50 | 45 |
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