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Which historical text, from any point in time, that we are aware of but not in possession of would be of greatest value to mankind if it were to be suddenly found? | The [Q document](_URL_0_) (a hypothesized early record of Jesus's teachings used as a source by the gospel writers) would be of enormous religious and cultural significance if an extant copy ever turned up.
Edit: This is a pretty interesting shot at a reconstruction of what Q might have looked like: [The *Logia*](_URL... | [
"Widney said in \"Civilizations and Their Diseases\" (1937), I have never written for money. The sole object has been the carving out of broader lines for the human race. For more than fifty years of careful historical study, I have thought, and planned, and worked to this end. This ultimate purpose has run through... |
If acoustic energy is converted to heat when a material absorbs sound, is it possible for an audio source to produce enough acoustic energy to ignite something? | It IS possible, though as you said yourself highly
improbable. Sound is simply the vibration of particles in the air (hence why there's no sound in space) and that vibration hits and object and can vibrate it or induce heat, which is why you can break glass with a sound (not the only reason, mind you). If you played a ... | [
"Absorbing sound spontaneously converts part of the sound energy to a very small amount of heat in the intervening object (the absorbing material), rather than sound being transmitted or reflected. There are several ways in which a material can absorb sound. The choice of sound absorbing material will be determined... |
What was the input of the Polish people in the second WW? How did they contribute. | Here's a brief answer:
Before the war Polish agents passed to the British an Enigma machine, which enables the British to be aware of how it worked even if its possession did not solve the problem of how to break German codes.
Polish units and individuals escaped to the West in 1940. Many pilots joined the French Ai... | [
"It was the Polish contribution to the Allied war effort in the United Kingdom that led to the establishment of the postwar Polish community in Britain. During the Second World War, most of the Poles arrived as military or political émigrés as a result of the German and Soviet occupation of Poland. \n",
"During t... |
How strong is the link between benzodiazepines and dementia/Alzheimer's? What about marijuana? | Tried looking up a few studies for you. A retrospective study in France found that in those with dementia, there was a higher rate of exposure to psychotropic and anti-psychotic drugs, with anti-psychotic exposure having the highest association with dementia. Hypnotics/anxiolytics such as benzodiazepines carried a lowe... | [
"A number of studies have drawn an association between long-term benzodiazepine use and neuro-degenerative disease, particularly Alzheimer's disease. It has been determined that long-term use of benzodiazepines is associated with increased dementia risk, even after controlling for protopathic bias.\n",
"The long-... |
What would you see from inside the event horizon of a singularity? | RobotRollCall has the answers you seek.
_URL_0_ | [
"An observer crossing the event horizon of a non-rotating and uncharged (or Schwarzschild) black hole cannot avoid the central singularity, which lies in the future world line of everything within the horizon. Thus one cannot avoid spaghettification by the tidal forces of the central singularity.\n",
"As with the... |
what is the difference nutritionally between artificial and natural sugars, like why are the sugars from my apple any better for me than the sugars from my apple lollipop if it’s all still sugar? | Well there's not a chemical difference between the fructose in the apple and the fructose in the lollipop. There are two reasons the apple is better for you. 1. The apple has some vitamin C and probably others 2. The apple has dietary fiber and other complex carbs, which will lead to a smoother blood sugar curve than i... | [
"Sugar-apple is high in energy, an excellent source of vitamin C and manganese, a good source of thiamine and vitamin B, and provides vitamin B, B B, B, iron, magnesium, phosphorus and potassium in fair quantities.\n",
"A sugar substitute is a food additive that provides a sweet taste like that of sugar while con... |
What is the smallest particle our skin can feel? | On the fingertip, you can sense the orthogonal displacement of your skin with a detection threshold of roughly 25 microns at 0.5 Hz (a 2 second smooth displacement). At 60 Hz for a half second that threshold is under 10 microns, and it drops to 1-2 microns at 250-300 Hz.
For movement parallel to the surface of t... | [
"Another type, \"microscopic particles\" usually refers to particles of sizes ranging from atoms to molecules, such as carbon dioxide, nanoparticles, and colloidal particles. These particles are studied in chemistry, as well as atomic and molecular physics. The smallest of particles are the \"subatomic particles\",... |
why does long division work? | Lets do 123/5 with the same steps as in long division but in more rigorous fashion.
123 can be written as 1×100 + 2×10 + 3×1 (or with exponents as 1×10^2 + 2×10^1 + 3×10^(0). We'll need this later).
So now we have ( 1×100 + 2×10 + 3×1 ) / 5.
We can write this as
( 1×100 ) / 5 + ( 2×10 ) / 5 + ( 3×1 ) / 5
And furth... | [
"In arithmetic, long division is a standard division algorithm suitable for dividing multi-digit numbers that is simple enough to perform by hand. It breaks down a division problem into a series of easier steps.\n",
"In arithmetic, short division is a division algorithm which breaks down a division problem into a... |
What are the exact criteria with which historians can consider a past event to be a historical fact? | Let me start by proposing that history is not a mere pile of facts that we prove or disprove one by one and add to the pile. There are many things that may or may not have happened, but we can still learn lots from them.
A great example of this is in the book by Alfred Fabian Young, *The Shoemaker and the Tea Party: ... | [
"A historical event can be defined as any occurrence from the past regardless of significance, with the term \"history\" an umbrella term relating to past events and any associated memories, discoveries, collections, organizations, presentations, and/or interpretations of them. This differs from a historic event wh... |
why does the healed skin on my wounds have the same patterns, wrinkles and creases as before? | Look at your hand, now move the inside of the base of your thumb towards your pinky. See all the folds and such? Your skin will fold the same way even after scarring.
Another example is that I game about as often as someone with a fulltime job is at work (30ish hours a week) my hand positioning presses the pinky side ... | [
"Fascia becomes important clinically when it loses stiffness, becomes too stiff or has decreased shearing ability. When inflammatory fasciitis or trauma causes fibrosis and adhesions, fascial tissue fails to differentiate the adjacent structures effectively. This can happen after surgery where the fascia has been i... |
Are hydrogen and oxygen molecules constantly forming new liquid water, or has all the water that can exist on earth already been formed? | Water is continually being created and destroyed by a number of natural processes. Probably the two fastest are the HOx cycle in the atmosphere:
O3 + photon ( < 300 nm wavelength) = > O2 + O(1D)
O(1D) + H2O = > 2OH
OH + organic compd. = > H2O + products
and photosynthesis:
xCO2 + xH2O = > (CHO)x + xO2
an examp... | [
"\"Stephan Riess of California formulated a theory that \"new water\" which never existed before, is constantly being formed within the earth by the combination of elemental hydrogen and oxygen and that this water finds its way to the surface, and can be located and tapped, to constitute a steady and unfailing new ... |
If the moon is spinning, why do we always see the same face? | It's called tidal locking. Gravitational force depends on the square of the distance. For objects that are close enough and big enough to us, there is a significant variance in the gravitational force on one side versus the gravitational force on the other side. The side of the moon facing us isn't heavier, but because... | [
"The Moon is in synchronous rotation as it orbits Earth; it rotates about its axis in about the same time it takes to orbit Earth. This results in it always keeping nearly the same face turned towards Earth. However, because of the effect of libration, about 59% of the Moon's surface can actually be seen from Earth... |
How would soft drinks (Carbonated) behave in space? | I remember a post on Reddit a while back about how both Coke and Pepsi had delivered soda to the ISS. Both times it ended in disaster because there isn't gravity to get the CO2 bubbles to rise up into a burp. Instead the gas stays in your stomach, accumulating, until you vomit it up. Along with a bunch of other liquid ... | [
"Carbonated drinks have been tried in space, but are not favored due to changes in belching caused by microgravity; without gravity to separate the liquid and gas in the stomach, burping results in a kind of vomiting called \"wet burping\". Coca-Cola and Pepsi were first carried on STS-51-F in 1985. Coca-Cola has f... |
why is it ok to pray to statues and pictures of jesus if there’s a commandment against graven images? | The commandment is to have no other God's not no pictures, in Catholicism. Islam forbids images because they worry about exactly what has happened in the Catholic Church before where the symbols and pictures became more....up front important for lack of a better way of putting it. Can't say it's a bad idea, just think ... | [
"Latter-day Saints do not generally approve of or own crucifixes, and do not typically have statues in their local ward meeting houses, though some have been erected in LDS Visitor Centers and elsewhere. Portraits of Jesus, together with photographs or paintings of current and/or past church leaders, are allowed in... |
How are scientists getting estimates of 40-80% of populations that will contract the Coronavirus? | Herd immunity is the upper bound.
For measles, polio, and other prolific viruses its around 80%. This is what people with suppressed immune systems (who cant recieved vaccinations) depend on to prevent getting those viruses.
Here's an article: _URL_0_
Basically, it's the worst case scenario. 100% of the population w... | [
"Consequently, the TMRCA estimated from a relatively small sample of viral genetic sequences is an asymptotically unbiased estimate for the time that the viral population was founded in the host population.\n",
"Coronaviruses have single-stranded, positive-sense RNA genomes of 26-30 kilobases, by far the largest ... |
If the universe is constantly expanding, how will it ever be possible to have the same temperature at every single point in space? | First, there are two relevant laws of thermodynamics for your question:
The zeroth law of thermodynamics says that if object A is in thermal equilibrium with object B, and B is in thermal equilibrium object C, then A is in thermal equilibrium with C.
The second law of thermodynamics says that the entropy of an isolat... | [
"If the topology of the universe is open or flat, or if dark energy is a positive cosmological constant (both of which are consistent with current data), the universe will continue expanding forever, and a heat death is expected to occur, with the universe cooling to approach equilibrium at a very low temperature a... |
Are there any instances of modern wars being won from a production disadvantage? | The Spanish Civil War was an interesting case of the initially (industrially) inferior side eventually winning the war. Although Spain was rather undeveloped compared to the rest of western Europe, it did have some industry.
When the war did break out, the Republic managed to maintain control over the most important ... | [
"Wars between capitalist states are, as a rule, the outcome of their competition on the world market, for each state seeks not only to secure its existing markets, but also to conquer new ones. In this, the subjugation of foreign peoples and countries plays a prominent role. These wars result furthermore from the i... |
what's the difference between a terrorist, a rebel and a separatist? | A terrorist is someone who intentionally does acts of violence in order to instill fear or 'terror' in people to affect change or to carry out an ideology or idea.
A rebel is someone who is a part of or builds a group of people trying to overthrow an existing government or president.
A separatist is someone who usua... | [
"The \"Nacionales\" or Nationalists, also called \"insurgents\", \"rebels\" or, by opponents, \"Franquistas\" or \"fascists\" —feared national fragmentation and opposed the separatist movements. They were chiefly defined by their anti-communism, which galvanised diverse or opposed movements like Falangists and mona... |
Whatever happened to the Magi? | They are known by different names now. 'Magi' during the classical Greek period came to mean generally anyone skilled at astrology and so it was not specific to Zoroastrianism or a priesthood (think of the three wise men i.e 'magi' of the bible - the word there just means 'wise king' (wise because they knew to follow t... | [
"The magi were a group of on-site Zoroastrian observers, located in their separate but attached structure possibly a caravanserai, paid and cared for by the Achaemenid state (by some accounts they received a salary of daily bread and flour, and one sheep payment a day). The magi were placed in charge of maintenance... |
why does the internet hate skrillex so, so much? | I can't speak for the internet, but I can provide a logical explanation. I think we can both agree that not many people like dubstep. Skrillex is the face of neo-dubstep. When people despise something, they look at its most popular representation and hate him/her.
Basically, skrillex represents dubstep, people hate d... | [
"In a positive review for \"MSN Music\", Robert Christgau called \"Bangarang\" an \"electronical vista\" and said it is \"a pop record because its shamelessly hedonistic barrage of proven dancefloor tricks will obviously be more fun at home than in a club.\" August Brown of the \"Los Angeles Times\" felt that, alth... |
Why don't waves through water travel at the speed of sound in water? | Waves like sound transport potential and kinetic energy through vibration and excitation. There is no mass transit.
Water waves transport these energy forms as well but also exchange mass, causing impulse exchange and therefore viscosity effects to enter the picture. | [
"The influence of sonic waves traveling through liquids was first reported by Robert Williams Wood (1868–1955) and Alfred Lee Loomis (1887–1975) in 1927. The experiment was about the frequency of the energy that it took for sonic waves to \"penetrate\" the barrier of water. He came to the conclusion that sound does... |
How accurate is the show The Tudors? | I just finished watching it recently, so I looked into it. However, as I'm not expert on Tudor England, I'm just going to talk about a few specific things that I'm confident of.
The first, is the order of events and specifically their time. Sometimes the show changes the order of unrelated events slightly.
The show ... | [
"The Tudors is a historical fiction television series set primarily in 16th-century England, created and written by Michael Hirst and produced for the American. premium cable television channel Showtime. The series was a collaboration among American, British, and Canadian producers, and was filmed mostly in Ireland... |
How can we hope to detect faint intelligent signals from exoplanets when we aren't even able to detect the light from those planets? | Well... the problem with seeing an exoplanet is that the star is so bright you can't get a long enough exposure to see the planet's light. (like trying to see a speck of dust near a spotlight) There are some neat strategies to work around this, like a giant shadow-casting shield that you'd space in front of your telesc... | [
"In 2018, astronomers noted, \"Detecting SIMP J01365663+0933473 with the VLA through its auroral radio emission, also means that we may have a new way of detecting exoplanets, including the elusive rogue ones not orbiting a parent star ... This particular object is exciting because studying its magnetic dynamo mech... |
When you ingest salt NaCl what does the body do with the chlorine after the sodium is absorbed? | [NIH Glossary - Chloride](_URL_0_) | [
"Sodium chlorite is derived indirectly from sodium chlorate, NaClO. First, sodium chlorate is reduced to chlorine dioxide, typically in a strong acid solution using reducing agents such as sodium sulfite, sulfur dioxide, or hydrochloric acid. This intermediate is then absorbed into a solution of aqueous sodium hydr... |
Can any given 2D shape be expressed as a single (probably incredibly complex) equation, or do many shapes require a piecewise graph? | Yes. I used to waste so much time in high school typing long formulas into my TI-83 to get it to graph shapes I drew out ahead of time on graph paper. With enough time on your hands, you can use its parametric grapher to graph out your signature.
I used the [Nyquist-Shannon sampling formula](_URL_0_). It smoothly inte... | [
"Geometric shapes are often represented as 2D curved surfaces, 2D surface meshes (usually triangle meshes) or 3D solid objects (e.g. using voxels or tetrahedra meshes). The Helmholtz equation can be solved for all these cases. If a boundary exists, e.g. a square, or the volume of any 3D geometric shape, boundary co... |
How did the sections of US states become known as "counties" even though they have never been ruled by counts? | Point of order: The British counties have never been ruled by counts (or viscounts): it stems from the Normans, who simply took over the Saxon shires (that's why it's all "Hampshire", "Cheshire", "Renfrewshire" etc.), but brought their Norman French with them (counts actually being a thing on the continent).
Historica... | [
"Counties in U.S. states are administrative divisions of the state in which their boundaries are drawn; for example the territorially medium-sized state of Pennsylvania has 67 counties delineated in geographically convenient ways. By way of contrast, Massachusetts, with far less territory, has massively sized count... |
Modern day concrete still doesn’t compare to the concrete made by the Romans. How was the recipe lost? | I don't mean to discourage further discussion, but this topic emerges quite often. You might want to read the response by /u/TectonicWafer in [this discussion](_URL_0_). For some additional insight, you may also read the short discussion about 'losing knowledge' [here](_URL_1_). | [
"Roman concrete, also called opus caementicium, was a material used in construction during the late Roman Republic until the fading of the Roman Empire. Roman concrete was based on a hydraulic-setting cement. Recently, it has been found that it materially differs in several ways from modern concrete which is based ... |
the difference between a particulate, gas, and vapor | * Particulate - small solid particles dispersed into the are
* Vapor - individual molecules mixed in with the air, but not at high enough of a temperature to be a gas...sometimes incorrectly used as a synonym for gas
* Gas - molecules travelling at high enough speed they cannot for the temporary and permanent bonds tha... | [
"In physics, a vapor (American English) or vapour (British English; see spelling differences) is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is di... |
Do male and female human genitalia exhibit a similar degree of variation in length and width? | There definitely is substantial variation in the size of the female reproductive tract, but I am not aware of any studies that actually try to compare the variability to that for penises.
It would be a challenging study because the vagina both opens up and lengthens quite substantially during arousal and at different ... | [
"There is significant sexual dimorphism in the genus. Males measure in length, while females are slightly longer at . The subgenital plate is longer in the male than in the female. Females are easily distinguished from males by the presence of a large, sword-shaped ovipositor which measures nearly half the length o... |
is the united states currently at war? | We are at war in virtually any meaningful sense, we have just refused to call it such because that word has real legal and political ramifications. | [
"The US has been on the ground and directly involved in the 17-year old war that analysts have described as stalemate. Ending the 17-year conflict has eluded former US presidents and Donald Trump has said that he considers the war too costly.\n",
"The war marked American entry into world affairs. Since then, the ... |
Do 2 atoms of the same element (I.e hydrogen) always weigh the same? Why or why not? | No, two atoms of the same element will not always have the same mass. Two atoms of the same element can have a different number of neutrons in their nuclei. Since neutrons have a significant mass compared to electrons, this can lead to an important difference in mass between the various isotopes of an element. This fac... | [
"Equivalent weights were not without problems of their own. For a start, the scale based on hydrogen was not particularly practical, as most elements do not react directly with hydrogen to form simple compounds. However, one gram of hydrogen reacts with 8 grams of oxygen to give water or with 35.5 grams of chlorine... |
Did the Nazis view blonde-haired and blue-eyed Slavs and Jews as any better than the others? | The blond-hairs / blue eyes thing is actually a gross simplification of the racial policies of Nazi Germany. They were mainly obsessed with blood purity and Japanese were seen as vastly superior to the slavs despite not having blond hairs.
A good example of this obsession for blood purity was Reinard Heydrich, a high... | [
"In his early writings Ploetz credited Jews as the second highest cultural race after Europeans. He identified no substantial difference in \"racial character\" between Aryans and Jews, arguing that the mental abilities of Jews and their role in the development of human culture made them indispensable to the \"proc... |
what are the benefits of methadone/a methadone clinic? | It's an opiate like heroin so users wont withdraw and it's little less extreme. You can think of it like shorts with cigarettes, good for tapering off if you're trying to quit. | [
"While methadone clinics are generally considered to be effective treatment options for patients addicted to opioids, especially when other interventions have failed, there is controversy surrounding the placement of methadone clinics. There is a perception that the presence of the clinics attracts crime to surroun... |
How did RBMK reactors come to be and how were they different from other models used in the western world? | Briefly, the RMBK was a very unusual reactor design, optimized for the demands of the Soviet bureaucracy and production needs. The basic requirements that the RMBK was trying to satisfy were:
* the design had to be a relatively cheap way of producing gobs of electrical energy
* the reactor was designed to be capable ... | [
"The RBMK is an early Generation II reactor and the oldest commercial reactor design still in wide operation. Certain aspects of the RBMK reactor design, such as the active removal of decay heat, the positive void coefficient properties, the graphite displacer ends of the control rods and instability at low power l... |
How long does it take for a particle to loop around LHC? How much does it change for the particle due to time dilation? | _URL_0_
> When running at full design power of 7 TeV per beam, once or twice a day, as the protons are accelerated from 450 GeV to 7 TeV, the field of the superconducting dipole magnets will be increased from 0.54 to 8.3 teslas (T). The protons will each have an energy of 7 TeV, giving a total collision energy of 14... | [
"Today, time dilation of particles is routinely confirmed in particle accelerators alongside with tests of relativistic energy and momentum, and its consideration is obligatory in the analysis of particle experiments at relativistic velocities.\n",
"Time dilation as predicted by special relativity is often verifi... |
if sea level has been rising then how come it is not evident from the beach yet? | The sea has risen by about 15cm due to the 0.8^o C rise in global temperatures so far; this is not enough to notice on a typical beach without careful measurement.
Some places, such as Tuvalu and Bangladesh, have experienced more drastic and obvious effects due to the rise.
Scientists are concerned that the rise wil... | [
"In addition, rises in sea level thought to be due to global warming appear likely to make low-lying areas of land increasingly susceptible to flooding, while in some areas the coastline continues to erode at a geologically rapid rate.\n",
"In addition, rises in sea level thought to be due to global warming appea... |
Why do we feel comfortable in some positions and not others? | It has a certain degree to do with blood flow. This also explains why we roll around in bed at night- in some positions, blood may be restricted to some areas due to pressure on the blood vessels, so we roll to another position to redistribute the bloodflow.
How comfortable you are in a position whilst concious is lik... | [
"BULLET::::- If two people of different social standings talk to each other, the person with a higher position usually takes a more relaxed attitude. Their posture may be unbalanced, relaxed, and may appear to be nonchalant. A person with a lower position often maintains symmetrical posture by placing both hands on... |
food stamp fraud | Vendors (grocery stores, etc) receive reimbursement from the government for accepting food stamps as payment for (approved) food items. Things that cannot be purchased with them include non-food items, hot pre-prepared foods, as well as cigarettes and alcohol.
What she was doing was allowing people to pay for non-e... | [
"Department of Agriculture v. Moreno, 413 U.S. 528 (1973), was a United States Supreme Court case that declared a provision of the Food Stamp Act denying food stamps to households of \"unrelated persons\" to be a violation of the U.S. Constitution. The Court held that provision to be irrelevant to the stated purpos... |
why does your neck get tense when you’re stressed and how does a massage fix it? | When you are stressed, you experience fight-or-flight, even if the stressor is emotional/psychological in nature. When this response occurs, it causes you to produce more adrenaline. Adrenaline causes muscle tension (muscle tension being a sign of stress). If you massage a muscle, you can cause that muscle to relax.... | [
"Progressive muscle relaxation helps relax your muscles by tensing certain parts of the body (such as the neck), and then releasing the tension in order to feel the muscles relaxing. This technique helps for people with anxiety because they are always tense throughout the day.\n",
"A study by Thomas and Siever sh... |
Knowledge of coats of arms in medieval Europe | Yes, a noble was supposed to know the coat of arms of at least the important lords, at least in his own army (because it's rather easy to deduce who's an enemy when you know who's your friend).
The most notable example for this (or rather for it's absence, from which a presumed knowledge for nobles can be inferred) is... | [
"The first evidence of medieval coats of arms is found in the Bayeux Tapestry from the 11th century, where some of the combatants carry shields painted with crosses. Coats of arms came into general use by feudal lords and knights in battle in the 12th century. By the 13th century arms had spread beyond their initia... |
Do any animals live at the extreme poles and how do they survive? | > A lone polar bear, tracks of an Arctic fox, unidentified sea creatures, and several birds have been observed at the North Pole over the years.
[Source](_URL_0_) - you still have the ocean as food source.
At the South Pole: Technically humans live there, and a few animals live on them. But outside the research sta... | [
"Because totem poles are created from an organic material they can be a place of habitat for many diverse species. They can become an ideal home for many insects such as wasps, bees, carpenter ants or termites. In addition, poles make great homes for birds as many nests have been found at the top of poles. Biologic... |
how do tolls work? do you really get in trouble for running one? | You mean on a road? A machine will take a photo of your license plate if you go through without paying. Some offer an option to pay the toll afterward, by Web or by mail. (Some don't have that option.) You may get a fine/ticket in the mail if you don't pay. | [
"To solve the problem, some toll officials now collect tolls by actually walking to cars in the line and collecting tolls and handing over receipts. This somewhat alleviates the problem, even though the core of the problem is still existent to this day.\n",
"Toll restriction or toll denial is a feature offered by... |
What are the best sources to understand Gaius Marius's reforms in Rome? | Sorry it took me a while, hope this is helpful. The bibliography from my old Marian Reforms paper follows. Especially useful were Gabba, Kildahl, Smith. If you want my full paper (with page numbers for references) let me know, I'll find a place to put up the pdf or you can PM me with an email address. Cheers.
Adc... | [
"His research has focused mainly on Roman history of the Republican and early imperial periods, and in particular on three aspects, namely war, imperialism and international relations; Roman historiography; and the transition from Republic to monarchy under Augustus. These themes have been explored in his monograph... |
how did humans in asia evolve to have narrower eyes, why did africans skin stay black while arabic and european peoples became lighter? | If you live in the tropics, dark skin is a helpful adaptation, because it protects your skin from sunlight (fewer sun burns and cancers).
If you live in the northern latitudes where there is significantly less sun certain times of the year, light skin is a helpful adaptation, because it allows more sunlight to penetra... | [
"Convergent evolution in humans includes blue eye colour and light skin colour. When humans migrated out of Africa, they moved to more northern latitudes with less intense sunlight. It was beneficial to them to reduce their skin pigmentation. It appears certain that there was some lightening of skin colour \"before... |
Wehrmacht Clean Hands in the West? | As for Rommel specifically: more can be written on this, but you might want to read ["Rommel's legacy"](_URL_0_) by /u/commiespaceinvader.
EDIT: As for the source of the Wehrmacht Clean Hands myth, I suggest the reply to ["Did the Rommel Myth and Clean Wehrmacht myth (and others) pushed after World War II come from Go... | [
"The Wehrmacht: History, Myth, Reality is a 2002 book by German historian Wolfram Wette which dealt with the issue of Wehrmacht's criminality during World War II and the legend of its \"clean hands\". The original German-language book was translated into five languages; the English edition was published in 2006 by ... |
Could we just inject dopamine and other molecules that cause feelings of well-being into our bodies and stay happy for the rest of our lives? | There is no safe or effective happiness treatment. Short term happy pills (e.g. cocaine, which causes elevation in levels of dopamine right in the areas that cause you to feel happy) don't work for long.
> If we could, every other human activity would be pointless, as we only do such things to be happy( i.e. ge... | [
"On the positive side, enhanced emotional well-being is seen to contribute to upward spirals in increasing coping ability, self-esteem, performance and productivity at work, and even longevity. Thoughts determine our feelings, and thoughts are nothing more than firings of neurons. And those feelings that our though... |
*How* do left/right handed molecules form and how are they different? | Your left hand is structurally distinct from your right hand. In other words, there's no orientation, rotation or any translation that will turn your right hand into your left hand. What this means is there's absolutely no way to put your left hand in a right handed glove and vice-versa (have a go).
This chirality, as... | [
"The right hand side is a sum over conjugacy classes of the group , with the first term corresponding to the identity element and the remaining terms forming a sum over the other conjugacy classes (which are all hyperbolic in this case). The function has to satisfy the following:\n",
"The left side is a volume in... |
what causes things to sound differently such as a breaking glass sound vs typing on a keyboard? | Sound is air vibrating. The air vibrates because it's being bumped into by a surface that's vibrating. Those surfaces have different characteristic amplitude and frequencies due to their materials, construction and size. So a large, flappy piece of paper is going to make very different vibrations than a big brick, when... | [
"An acoustic piano usually has a protective wooden case surrounding the soundboard and metal strings, which are strung under great tension on a heavy metal frame. Pressing one or more keys on the piano's keyboard causes a padded hammer (typically padded with firm felt) to strike the strings. The hammer rebounds fro... |
How was King Alfred able to beat the Vikings? | Honestly whole books and theses have been written on this.
I've written a little about it [here](_URL_0_).
For reading I would recommend Hill *et al*, *The Defence of Wessex*; Baker and Brookes, *Beyond the Burghal Hidage*; Reynolds *et al*, *Landscapes of Defence*; Stenton, *Anglo-Saxon England*; Lavelle, *Alfred's ... | [
"In 878 King Alfred of Wessex defeated a Viking army at the Battle of Edington. Guthrum, the Viking leader, retreated with the remnants of his army to their \"stronghold\", where Alfred besieged him. After fourteen days the Vikings \"thoroughly terrified by hunger, cold and fear\" sought peace and sent an emissary ... |
What is human skin actually made up of? Is it technically a human organ? | An organ is a collection of tissues that perform a specific function. The skin is an organ that provides protection from the outside world to our viscerals.
There are three layers to the skin: the outermost **epidermis**, the **dermis**, and the underlying **hypodermis**. The epidermis is almost entirely kerati... | [
"The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue and guards the underlying muscles, bones, ligaments and internal organs. Human skin is similar to most of the other\n",
"The skin is the largest organ in the... |
is this paper about roundup being dangerous legit? | > Consequences are most of the diseases and conditions associated with a Western diet, which include gastrointestinal disorders, obesity, diabetes, heart disease, depression, autism, infertility, cancer and Alzheimer’s disease.
That seems sketchy, just reading the abstract... | [
"In the \"In re: RoundUp Products Liability\" multidistrict litigation (MDL) a \"Daubert\" hearing was held in March 2018 on general causation as to non-Hodgkin’s lymphoma. This case consolidated over 300 federal lawsuits that allege Monsanto did not adequately warn consumers about the risks of using RoundUp. These... |
Are all galaxies eventually going to become spiral galaxies? | It's actually the opposite. Objects will collapse and choose a favorable direction (due to angular momentum conservation) only if there is significant friction during gravitational collapse so that kinetic energy is transformed into heat (and light). So disks only form if most of the matter is in gas rather than stars.... | [
"Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work \"The Realm of the Nebulae\" and, as such, form part of the Hubble sequence. Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. Th... |
how does isothermal clothing work? | Actually I don't think it does. it's just a marketing gimmick. usually, it's a base layer that's made to trap some air between your skin and the clothing (for insulation). in the old days, it was just little dimples they have grander schemes now and haven't found they work any better, it just allows them to use more pl... | [
"BULLET::::- A \"sports towel\", or (synthetic) chamois, is a towel originally developed for swimmers and divers, favored for its super-absorbent qualities. Sports towels can be wrung out when saturated, leaving the towel able to absorb water again, although not dry. Those qualities, along with their compact nature... |
disney world is such a money maker, why are the cities surrounding it so poor with such a housing crisis? | Because that money does not go back to the local economy. It instead gets funneled to corporate accounts, and the corporate team doesn't live in these neighborhoods.
A company doing well only helps the local area if they put the money back in. For example paying workers well, ordering supplies from local companies, ... | [
"The city is facing financial challenges. In late 2016, it had a major deficit in its budget and debts in excess of €400 million. \"In effect, the place is bankrupt\", according to a report by The Guardian. Many locals are leaving the historic center due to rapidly increasing rents. The declining native population ... |
Did radio have a reputation as being vapid or intellectually detrimental, the way TV does today? | I've only come up on this tangentially, but as it turns out: Yes, in the early 20th century there was a lot of opposition to radio as a form. As early as 1923 we start seeing anti-radio editorials such as an op-ed on the Times (of London), by one Douglas Hacking (then MP). In it, he calls "the wireless" a "maddeningly ... | [
"Major technological innovations transformed the mass media. Radio, already overwhelmed by television, transformed itself into a niche service. It developed an important political dimension based on Talk radio. Television survived with a much reduced audience, but remained the number one advertising medium for elec... |
why do most bipedal robots always keep their knees bent a bit when standing? | I'm still an industrial electronics student but if I had to guess I would say that it is because when engineers program robots they are given a "home position" that the robot stays in. In this case the home position is the one that best allows the robot to react to varying conditions. Like if the robot were to step in... | [
"Legged robots can be categorized by the number of limbs they use, which determines gaits available. Many-legged robots tend to be more stable, while fewer legs lends itself to greater maneuverability.\n",
"Legged robots may have one, two, four, six, or many legs depending on the application. One of the main adva... |
how does the body "know" to try and reattach itself to a severed limb? | Uhm, it totally doesn't.
I'm having difficulty understanding what you are asking, exactly. Like, let's say I am trying to fix my lawnmower when a neighbor kid herpderps over and turns the motor on. Off goes my left hand.
My left wrist is NOT sending signals to my brain saying "Look! The hand is right there! Let's rea... | [
"During the procedure, the person is under regional or general anesthesia. A surgical tourniquet prevents blood flow to the limb. The skin is often opened with a zig-zag incision but straight incisions with or without Z-plasty are also described and may reduce damage to neurovascular bundles. All diseased cords and... |
how does anxiety cause one to experience feeling unattached to one's body, or "derealization"? | It's a coping mechanism; really short answer, dissociation/derealization is a defense mechanism to deal with stress or trauma. Not being there = not having to deal with the stressful situation. If you need me to expand on it I can. :o
Source: I have severe dissociation and dissociative identity disorder | [
"Auras can also be confused with sudden onset of panic, panic attacks or anxiety attacks creating difficulties in diagnosis. The differential diagnosis of patients who experience symptoms of paresthesias, derealization, dizziness, chest pain, tremors, and palpitations can be quite challenging.\n",
"The biological... |
why the value of so many western currencies is roughly equal? | Many of these currencies are or were pegged to the USD after WWII. Since the United States had the vast majority of the world's gold (lend-lease was expensive, as it turns out), the agreement was that the USD would be backed by gold and the other currencies would be backed by the Dollar. (The [Bretton Woods](_URL_0_) s... | [
"The major currencies (except the Japanese yen) are traditionally priced to four decimal places, and a pip is one unit of the fourth decimal point: for dollar currencies this is to 1/100th of a cent. For the yen, a pip is one unit of the second decimal point, because the yen is much closer in value to one hundredth... |
How would schizophrenia manifest itself in someone who was deaf or raised isolated from language? Would the voices be manifested elsewhere in their sensory system? | Here are a few things to consider:
(1) If a deaf person has visual hallucinations of someone signing to them, this is not equivalent to having delusional thoughts in sign language. In schizophrenia, delusions can arise with or without hallucinating voices or signs, and these delusions have more to do with cognition th... | [
"Another typical disorder where auditory hallucinations are very common is dissociative identity disorder. In schizophrenia voices are normally perceived coming from outside the person but in dissociative disorders they are perceived as originating from within the person, commenting in their head instead of behind ... |
why does eating more frequently increase your appetite? | Simple. You stomach is elastic. Eating a lot causes it to stretch and grow. Not eating a lot causes it to shrink. Your appetite always drives you to fill your stomach, whatever size it currently is, so if you eat a lot, it take more food to fill it since you are stretching it out (and I think it grows if it stretche... | [
"Appetite is the desire to eat food, sometimes due to hunger. Appealing foods can stimulate appetite even when hunger is absent, although appetite can be greatly reduced by satiety. Appetite exists in all higher life-forms, and serves to regulate adequate energy intake to maintain metabolic needs. It is regulated b... |
How does blue and red shift of a star occur if light is constant? | The wavelength and frequency both change, while the light maintains a constant speed.
The speed of a wave is equal to the length of a wave from peak to peak times the frequency, or how often a peak passes you as the wave travels by. Redshift corresponds to lower frequency and longer wavelength, and vice versa for blu... | [
"As the main star rotates on its axis, one quadrant of its photosphere will be seen to be coming towards the viewer, and the other visible quadrant to be moving away. These motions produce blueshifts and redshifts, respectively, in the star's spectrum, usually observed as a broadening of the spectral lines. When th... |
Why no aerial oxygen torpedoes for the Japanese? | The Japanese did develop an experimental oxygen-propelled aerial torpedo, the Type 94 in the early 1930s in parallel with the oxygen-propelled Type 93 and Type 95. The Navy Technical Arsenal found that the Type 94 was too complicated and maintenance- intensive for an aerial weapon. The main advantage of an oxygen torpe... | [
"The oxygen Long lance torpedo, which used pure oxygen instead of air for the oxidizer, was developed by the Japanese just prior to their full involvement in WWII. Despite having more than twice the effective range of the best Allied torpedoes and lacking the tell-tale torpedo wake, the oxygen torpedo was not used ... |
do wifi signals face resistance when passing through walls? | Yes, but walls aren't always the big issue!
Waves can be absorbed by walls, reflected off of surfaces like windows and metal panels, and they can be grounded really easily.
I used to do a bit of RF work and we found the biggest thing that hampered us was either metal fences (didn't matter that they're full of holes, ... | [
"It's practical in some cases to apply specialized wall paint and window film to a room or building to significantly attenuate wireless signals, which keeps the signals from propagating outside a facility. This can significantly improve wireless security because it's difficult for hackers to receive the signals bey... |
how exactly does a power strip work? | The outlets in a power strip are wired up in parallel. As you plug more items in the load does increase. Most power strips have a circuit breaker on them that will trip if you exceed the load, if not your outlet should have a circuit breaker as well. It is entirely possible to overload a power strip, it is just mos... | [
"A power strip is a block on the end of a power cable with a number of sockets (usually 3 or more), often arranged in a line. This term is also used to refer to the whole unit of a short extension cord terminating in a power strip.\n",
"A power strip (also known as an extension block, power board, power bar, plug... |
how are our intestines able to sort between gas, liquids and poo? | Liquid is extracted by the large intestine. Essentially the large intestine has chemical pumps that take advantage of osmosis to force water out of the intestines and into the body. Salt is pumped into the liquid between the cells and this causes osmosis to push water into that liquid and from there the bloodstream. ... | [
"Digestion occurs in the intestine, with the caecum producing further digestive enzymes. An additional tube, called the siphon, runs beside much of the intestine, opening into it at both ends. It may be involved in resorption of water from food.\n",
"The small intestine is the part of the digestive tract followin... |
how does a surveying work? | Basically it is a measuring device to measure angles and distances, and elevation.
So a building is designed on a computer model of the site. You need a way to take that electronic information and place it on the real ground so the guys actually building the building know where to build the building, or the new road o... | [
"Surveying or land surveying is the technique, profession, art and science of determining the terrestrial or three-dimensional positions of points and the distances and angles between them. A land surveying professional is called a land surveyor. These points are usually on the surface of the Earth, and they are of... |
Will swirling my coffee in it's cup cool it down faster, slower, or have no impact? | faster, the coffee is in contact with more of the cups surface area, plus more evaporated cooling, and mixing the hottest coffee at the top with the coolest from the bottom. If you're using a metal spoon, it'll absorb some heat too. | [
"When placed beneath a cup, saucers have very little direct influence on beverage cooling rate. For hot, water based beverages (e.g. tea or coffee), cooling rate in a cup is typically dominated by evaporation, which occurs across the free surface in contact with the air. Heat transfer through the bottom of the cup ... |
why does it take some people longer than others to be alert upon waking? as in, why does it take some people longer to really "wake up"? | Cortisol production also has to do with this. Some people make more cortisol in their sleep. These people tend to appear to "snap awake"... _URL_0_ (edit: I just woke up and forgot to link to the wiki-sauce). | [
"Today, many humans wake up with an alarm clock; however, people can also reliably wake themselves up at a specific time with no need for an alarm. Many sleep quite differently on workdays versus days off, a pattern which can lead to chronic circadian desynchronization. Many people regularly look at television and ... |
the artistic value of rothko's orange, red, yellow painting | Like everything else, something is worth what another person is willing to pay for it. A sub that focuses on art work might be a better place. | [
"Souren Melikian of \"The New York Times\" described Rothko's \"Orange, Red, Yellow\" as one that \"...can convincingly be argued to be the most powerful of all his pictures\", Kelly Crow of \"The Wall Street Journal\" stated that \"The painting's trio of orange and yellow rectangles bobbing atop a cherry-red backg... |
What is the current historiographical opinion regarding Henri Pirenne's: Muhammad and Charlemagne. | In a nutshell (because the non-nutshell version would stretch across several already written books):
What holds:
* The Arab Conquests absolutely cemented (as one could argue that the Persian conquests did their number already) the breaking of the Mediterranean economic system, with catastrophic effects on the urban ... | [
"In a summary, Pirenne stated that \"Without Islam, the Frankish Empire would probably never have existed, and Charlemagne, without Muhammad, would be inconceivable.\" That is, he rejected the notion that barbarian invasions in the 4th and 5th centuries caused the collapse of the Roman Empire. Instead, the Muslim c... |
what is "dutch disease"? | The Dutch can breathe easy, because, contrary to popular belief, Dutch disease is not a flesh-eating disease in the Netherlands.
It's an economic term used to describe an indirect relationship between the usage of natural resources and agriculture. Exploitation of natural resources increases, agriculture declines. Now... | [
"The Dutch term usually specifically refers to the wave of disorderly attacks in the summer of 1566 that spread rapidly through the Low Countries from south to north. Similar outbreaks of iconoclasm took place in other parts of Europe, especially in Switzerland and the Holy Roman Empire in the period between 1522 a... |
what is canon? | The term was largely used when referring to the Bible. The many authors whose writings appear in the Bible wrote many other things as well. The pieces deemed "The Bible" were democratically selected by high ranking clergy. These are referred to as "Canon", while the many other writings of biblical authors are deemed... | [
"Canon law is the body of laws and regulations made by or adopted by ecclesiastical authority, for the government of the Christian organization and its members. It is the internal ecclesiastical law governing the Roman Catholic Church, the Eastern and Oriental Orthodox churches, and the Anglican Communion of church... |
why obama is criticized for going golfing? | It's part of the partisan bickering that comes with a two party system. If the President is a member of your party and takes a break, he's been working really hard and deserves it. If he's a member of the opposition, he's a lazy bum. | [
"In an October 3, 2011, interview with Fox News Channel's \"Fox & Friends\", Williams referred to a June golf game in which President Barack Obama and Republican House Speaker John Boehner had teamed against Vice President Joe Biden and Ohio Governor John Kasich, saying the match was \"one of the biggest political ... |
how can windmills compare to nuclear powerplants, where the generators spin with thousands of rounds per minute? | Windmills produce less power, that's why you build more of them | [
"For large, commercial size horizontal-axis wind turbines, the electrical generator is mounted in a nacelle at the top of a tower, behind the hub of the turbine rotor. Typically wind turbines generate electricity through asynchronous machines that are directly connected with the electricity grid. Usually the rotati... |
how does "trading futures" work? i've been told it's a good and cheap way to play the stock market, but everything i've read on it confuses me even more. | So I come up to you and say I will deliver to you, a ten pound ready-to-eat turkey on November 22nd if you give me $50 right now... and you think "that's a good price" and you give me fifty bucks.
I have just sold you a future comodity or service. We have just performed futures trading.
Now I've sold you that promise... | [
"Prices in futures markets play a special role in economic calculation. Futures markets develop prices for commodities in future time periods. It is in futures markets that entrepreneurs sort out plans for production based on their expectations. Futures markets are a link between entrepreneurial investment decision... |
how does the brita filter detector work? | it counts the number of times you tip the pitcher. it assumes that on average each time you tip it forward another glass of water has been poured out (and the LED will blink). the filter life is about 40 gallons, so it predicts when you've gotten close to the end of the useful life of the filter.
when the yellow LED s... | [
"An organ-pipe scanner is a system used in some radar systems to provide scanning in azimuth or elevation without moving the antenna. It consists of a series of waveguides and feed horns arranged in front of a shaped reflector, each one positioned to reflect the beam in a different direction. The wave guides meet a... |
how bi-planes are able to time/shoot their guns without the bullets hitting the propellers. | While all of the responses so far are good (the wiki link explains quite well in-depth, with illustrations), I'd like to try making this as ELI5/TL;DR as I can:
The pilot's trigger is not really the same as a trigger on a handgun - it does not make the weapon fire. Instead, it works more like a safety - when pressed d... | [
"Machine Gun turrets have a relatively low ceiling, given a turret at a reasonable elevation, an aircraft would likely be able to fly above the bullets unscathed. They are quick to fire, sending up bursts of 5 bullets at a faster rate than aircraft machine guns at quick, regular intervals. Depending on the aircraft... |
Are there any accounts of interviews with people who participated in lynchings 20, 30, or 40 years later? | Yes, contemporary interviews exist documenting the perspectives of those who participated, witnessed, in rare cases even those that survived lynchings. Interviews taking place some decades later are more difficult to find, but can be found in a few cases.
A powerful example comes from the [lynching of two men in Mari... | [
"The documented murders of 4,743 people who were lynched in the United States between 1882 and 1968 were not often publicized. It is likely that many more unrecorded lynchings occurred during and after this period which influenced The Great Migration of 6.5 million African Americans away from southern states. A 197... |
why is it unhealthy/more difficult for hunger’s sake to eat a 2000 calorie breakfast instead of lighter meals throughout the day? | Your body doesn't need 2000 calories all at once. If you eat a single 2000 calorie meal, then your body will use however many calories it needs at that moment, and then store the rest as fat to be used later. However, when you need calories a few hours later, it won't immediately dip into your fat reserves. Instead i... | [
"Breakfast, in particular, has been found to have a beneficial effect on children’s study, behaviour, and attendance and there is mounting evidence that eating a good quality breakfast reduces the risk of obesity. \n",
"BULLET::::- The Academy states that children who eat breakfast have better concentration, prob... |
Would it be possible to create helium-4 by introducing helium-3 to a neutron rich environment? | Yes, but this wouldn’t be a very good way of doing it. Most helium in nature is helium-4. So you’d have to gather helium, enrich it with helium-3, and then use the helium-3 to breed helium-4. Unless you have a source of helium which is already enriched in ^(3)He, and want to convert it to ^(4)He for some reason. | [
"Not all authors feel the extraterrestrial extraction of helium-3 is feasible. Dwayne Day, writing in The Space Review, identifies some major obstacles to helium-3 extraction from extraterrestrial sources for use in fusion, and questions the feasibility of extraterrestrial extraction when compared to production on ... |
why is it scary when kids sing or laugh or say nursery rhymes in horror movies/games? | Generally, it's done in a minor key where the tune is altered, so anything can be spoopy when done that way (Have you seen the Teletubby episode in black and white that plays a Joy Division Song over it?).
Also, one of the early films to do this was Nightmare on Elm Street where kids are jumping rope and singing 1-2... | [
"Nursery rhymes are short songs written for small children. The lyrics are usually simple and repetitive for easy comprehension and memorization. Although they are meant to be lighthearted and fun, they also function as an introduction to music and certain basic concepts learned through repetition and song. \n",
... |
Can electrons from a particular atom be anywhere in the universe but statisticaly nearly always in a definite zone near the core or there is places those electrons can't be? | Electrons can not exist within nodes. The number and shape of nodes is dependent on the orbital angular momentum. | [
"If these two electrons are correlated, then the probability of finding electron \"a\" at a certain position in space depends on the position of electron \"b\", and vice versa. In other words, the product of their independent density functions does not adequately describe the real situation. At small distances, the... |
Is squinting actually bad for your eyesight? | I don't know if it's bad for your eyesight or just a sign of bad eyes. Squinting will improve peoples vision slightly if they have bad eyesight which is why you might see people do that if they lost their glasses. Because of this reason it might have also made people think it was the cause of them needing glasses when ... | [
"It is a common belief that squinting worsens eyesight. However, according to Robert MacLaren, a professor of ophthalmology at the University of Oxford, this is nothing more than an old wives' tale: the only damage that can be caused by squinting for long periods is a temporary headache due to prolonged contraction... |
Operation Barbarossa caused massive Soviet casualities/incredible success for the Germans yet failed in capturing Moscow or force a surrender, was there a glaring tactical error that prevented this? | Logistics.
The campaign didn't start "late": the early summer months in Russia see significant rainfall, resulting in the so-called *rasputitsa*, literally "time without roads". Barbarossa's launch was timed so the ground could dry and the roads become usable again. In 1941 only 40,000 miles of the Soviet Union's 850,... | [
"In 1941 it was Russia's turn, yet Joseph Stalin refused to believe the multiple warnings of a German invasion. Operation Barbarossa began in June 1941, captured or destroyed multiple Soviet armies, and reached the gates of Moscow by December. Stalin fought back and forged close relations with Britain and the Unite... |
How much of an impact did the Civil War have on what is considered the Wild West? | You're gonna have a hard time getting any kind of a comprehensive answer to this question, as it's just too broad of a topic. It would be like asking, "what kind of an impact did World War II have on America in the second half of the 20th century?" The question itself is so open-ended and complex that you could run in ... | [
"The image of a Wild West filled with countless gunfights was a myth generated primarily by dime-novel authors in the late 19th century. An estimate of 20,000 men in the American West were killed by gunshot between 1866 and 1900, and over 21,586 total casualties during the American Indian Wars from 1850 to 1890. Th... |
I have a very specific question about the death of our star and supernovae (s?). Please look inside for details. | Without having many details at hand, and I'm sure someone can explain the fusion process better that I, Supernova are after all fusion has expired and caused by the mass of the red giant collapsing in on itself. this compression effectively blows the star apart (core-bounce) which is what a Type II Supernova is. so th... | [
"Supernovae can result from the death of an extremely massive star, many times heavier than the Sun. At the end of the life of this massive star, a non-fusible iron core is formed from fusion ashes. This iron core is pushed towards the Chandrasekhar limit till it surpasses it and therefore collapses.\n",
"WR star... |
How common was circumcision among the Pre-Islamic Arabs? We can safely assume that Christian tribes, namely the Banu Hanifa and the Banu Taghlib , would have abhorred the practice, but what about the rest? What about the Quraysh? | Tangential question, why would assume those Christian tribes would abhor it? | [
"Although there is some debate within Islam over whether it is a religious requirement, circumcision (called \"khitan\") is practiced nearly universally by Muslim males. Islam bases its practice of circumcision on the Genesis 17 narrative, the same Biblical chapter referred to by Jews. The procedure is not explicit... |
Are animals attracted to each other’s faces the way humans are? | Depends, i would assume some focus on colors, others on the rear-end etc... They haave specific evolutionary traits they look for.
Not all humans look at faces either, or find different types of faces attractive | [
"A major way that people relate to mammals (and some other animals) is by anthropomorphising them, ascribing human emotions and goals to them. This has been deprecated when it occurs in science, though more recently zoologists have taken a more lenient view of it.\n",
"Expressions of affection are displayed in th... |
If the earth's core cooled and solidified, would the planet get appreciably smaller? And if so, by how much? | Couldn't tell you exactly, but here's some estimates that are beyond rough. I'll have to make lots of assumptions.
Assuming we don't talk about condensates and such, then all material changes density depending on temperature. So I have to assume that we're only talking about the liquid core changing just barely enough... | [
"The Earth's inner core is thought to be slowly growing as the liquid outer core at the boundary with the inner core cools and solidifies due to the gradual cooling of the Earth's interior (about 100 degrees Celsius per billion years).\n",
"The growth of the inner core may be expected to consume most of the outer... |
can someone explain elasticity of demand and how it relates to the price of crude oil and other commodities? | I'll do my best, though I have a somewhat ameturish knowledgebase myself. Explaining it **like you're five**.
Lets say that you own a store. You want to have customers, so you set nice and low prices. It works and people come and buy your stuff. This is great but you need to make some money.
You want to find out: If... | [
"is the analysis of consumer demand, as indexed by the amount of a commodity that is purchased. In economics, the degree to which price influences consumption is called \"the price elasticity of demand.\" Certain commodities are more elastic than others; for example, a change in price of certain foods may have a la... |
White reflects, black absorbs. White radiates little, black radiates a lot. What do transparent materials typically do? | Transparent materials let most of the light pass through. Also, many "transparent" objects are opaque to other wavelengths of light. Something that lets visible light through might for instance block radio waves or vice versa.
Also, white *reflects* visible light through diffuse scattering. Black absorbs visible lig... | [
"Absorption of light is contrasted by transmission, reflection and diffusion, where the light is only redirected, causing objects to appear transparent, reflective or white respectively. A material is said to be black if most incoming light is absorbed equally in the material. Light (electromagnetic radiation in th... |
Do other mammals (or animals in general) "lose their voice" like we do? | **Disclaimer**: I wrote more than I meant to. If you don't want to read it all, the most important parts are the first and last paragraphs.
& #x200B;
Yes.... and no. The sounds made by all animals with lungs are made through vibrations in the larynx a.k.a. "voice box". In short, we (and other mammals) force air thro... | [
"Several non-human species demonstrate vocalizations that sound similar to human laughter. A significant proportion of these species are mammals, which suggests that the neurological functions occurred early in the process of mammalian evolution.\n",
"Most mammalian species produce sound by passing air from the l... |
why did chairman mao kill so many people including teachers? what could he have been trying to accomplish? | He was trying to purge China of The Four Olds as these were seen to only further the exploitation of the classes. The Four Olds are old customs, old habits, old culture, and old ideas.
A lot of teachers were executed publicly, monks were humiliated in the streets, a great number of Kung Fu masters took to the hills o... | [
"Benjamin Valentino noted that years after the conclusion of the campaign, Mao admitted that some people were \"unjustly killed,\" but insisted that \"\"basically there were no errors; that group of people should have been killed ... if they had not been killed the people would not have been able to raise their hea... |
Why are red and blue wavelengths of light most useful to photosynthesis? | Look [here](_URL_0_) Notice how on the left side of the total absorption graph everything is absorbed? If you are a plant, you don't want to be absorbing things in that region... so violet is less efficient than things to the right of it. | [
"Not all wavelengths of light can support photosynthesis. The photosynthetic action spectrum depends on the type of accessory pigments present. For example, in green plants, the action spectrum resembles the absorption spectrum for chlorophylls and carotenoids with absorption peaks in violet-blue and red light. In ... |
why can we still smell cigarette smoke i walk through when not breathing in? | The chemicals from cigarette smoke gets trapped in material (most likely fabric of some sort) and diffuses which is why you smell it. | [
"Sidestream tobacco smoke, or exhaled mainstream smoke, is particularly harmful. Because exhaled smoke exists at lower temperatures than inhaled smoke, chemical compounds undergo changes which can cause them to become more dangerous. As well, smoke undergoes changes as it ages, which causes the transformation of th... |
how do journalists find people? | Many people can be found through a phone book or a simple google search. Or you can call the company where you heard they work, or the school where you heard they study. Also, you can ask their current and former friends. | [
"A reporter is a type of journalist who researches, writes, and reports on information in order to present in sources, conduct interviews, engage in research, and make reports. The information-gathering part of a journalist's job is sometimes called \"reporting\", in contrast to the production part of the job such ... |
How thin (nanometer, atoms, etc..) can the human see, looking directly? | The visual resolution of the human eye is about 1 arc minute.
At a viewing distance of 20″, that translates to about 170 dpi (or pixels-per-inch / PPI), which equals a dot pitch of around 0.14 mm. LCD monitors today have a dot pitch of .18mm to .24mm.
Each persons vision is slightly different and some people have be... | [
"Atomic dimensions are thousands of times smaller than the wavelengths of light (400–700 nm) so they cannot be viewed using an optical microscope. However, individual atoms can be observed using a scanning tunneling microscope. To visualize the minuteness of the atom, consider that a typical human hair is about 1 m... |
if gps satellites lose time due to the lesser effect of gravity, why can't we just adjust the clock speed to make up the difference? | We *also* have GPS satellites adjust their clock speed themselves. But there are a lot of variables, so it would take a lot of processing power to compute the adjustments exactly; it's much more efficient to just make them kinda accurate and resync regularly. | [
"The effect of gravitational frequency shift on the GPS due to general relativity is that a clock closer to a massive object will be slower than a clock farther away. Applied to the GPS, the receivers are much closer to Earth than the satellites, causing the GPS clocks to be faster by a factor of 5×10^(−10), or abo... |
What do historians think of Foucault's "Discipline and Punish"? | I'll start by re-posting here several segments I've previously posted on punishment and Foucault.
> His influence is hard to *overstate* ... he's frequently accused (and rightfully so) for his very selective historical sources, and for not doing sufficient archival work, but in general he remains an essential touchp... | [
"Foucault has frequently been criticized by historians for what they consider to be a lack of rigor in his analyses. For example, Hans-Ulrich Wehler harshly criticized Foucault in 1998. Wehler regards Foucault as a bad philosopher who wrongfully received a good response by the humanities and by social sciences. Acc... |
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