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how do scientists/anthropologists explain the seemingly quick ascent of the human species? | [Punctuated Equilibrium, my man. Evolution of species or ideas shouldn't be be viewed as a gradual and constant change but as a series of leaps and bounds interspersed with periods of stability.](_URL_0_) | [
"Overwhelmingly, the idea of a \"first ascent\" is a modern one, especially in places such as Africa and the Americas with a history of colonialism. There may be little or no physical evidence or documentation about the climbing activities of indigenous peoples living near the mountain. For example, the volcano Llu... |
Is it possible to tack into the solar wind the same way we can sail into the wind on earth? | If you mean sailing in the opposite direction as the wind (i.e. to the Sun) then yes, it is possible, though not in the same way nor for the same reasons. Orbital dynamics are crazy and amazing :)
You can use [radiation pressure](_URL_0_) with a solar sail or the solar wind with an [electric sail](_URL_1_). In the rest of this comment I'll assume you have either of them.
Your spacecraft is initially in orbit around the Sun (assuming it's already escaped Earth's gravity). If you're orienting your sail at an angle, so that the net force on your spacecraft points in a direction opposite to its velocity, then you're causing it to slow down. Orbital dynamics mandate that an object in orbit that loses speed will come closer to the central attracting body (i.e. migrate to a lower orbit). If you keep losing and losing speed it will end up spiraling inwards.
Fun fact: even though the sail will cause it to lose speed, while getting closer to the Sun gravitational potential energy is released in the form of kinetic energy, effectively speeding up the spacecraft. The second effect is more significant; slowing down while in orbit actually makes the spacecraft move faster.
| [
"Robert L. Forward has commented that a solar sail could be used to modify the orbit of a satellite about the Earth. In the limit, a sail could be used to \"hover\" a satellite above one pole of the Earth. Spacecraft fitted with solar sails could also be placed in close orbits such that they are stationary with res... |
why do boobs in classical artworks look so different from those sported by today's models? [nsfw] | The models have all had surgery, or are naturally big-breasted.
In antiquity, it was considered more attractive to have smaller breasts, so the artists chose smaller-breasted women. | [
"Slides are well known for their sporty look because of the impact Adidas has left. They are very functional so they are great for casual outfits. For example going out to the beach, walking in parks, summer barbecues. However, high fashion designers such as Prada, Gucci, Burberry, and Marc Jacobs have included the... |
why was the race to the moon more important than the race to the first man in space? | They know him in Russia.
Because the Soviets sent a man into space first, the achievement was downplayed in the West, and then the Moon Race was really hyped up to compensate. | [
"According to US sources, the \"race\" peaked with the July 20, 1969, US landing of the first humans on the Moon with Apollo 11. Most US sources will point to the Apollo 11 lunar landing as a singular achievement far outweighing any combination of Soviet achievements. In any case the USSR attempted several crewed l... |
how was the bureau of census measuring population before sampling? | The census counts every person, or at least tries to, every ten years.
He is talking about people using the data collected - some of them insisted on using everything which, before modern computers could be a monumental task. | [
"Between 1790 and 1840, the census was taken by marshals of the judicial districts. The Census Act of 1840 established a central office which became known as the Census Office. Several acts followed that revised and authorized new censuses, typically at the 10-year intervals. In 1902, the temporary Census Office wa... |
how is airport security regulated and kept consistent around the world | It is not.
Every single country sets up their own rules and regulations, as well as how they enforce these rules and regulations. There are some countries who have treaties with others that set certain requirements for flights between said countries, but these are not always well enforced. | [
"Airport security attempts to prevent any threats or potentially dangerous situations from arising or entering the country. If airport security does succeed then the chances of any dangerous situation, illegal items or threats entering into an aircraft, country or airport are greatly reduced. As such, airport secur... |
What happens to the parts of the brain which control amputated body parts? | They exist, and can even be "tricked" into thinking an arm is still there which is basically phantom limb syndrome; it's also the basis for some robotic prosthesis which wouldnt work if the brain didnt retain those faculties; there are some local neurons that likely need to be developed, but the brain remains entirely undisturbed. | [
"Upper motor neurons in the primary motor cortex send their axons to the brainstem and spinal cord to synapse on the lower motor neurons, which innervate the muscles. Damage to motor areas by chance of cortex can lead to certain types of motor neuron disease. This kind of damage results in loss of muscular power an... |
what is the benefit of a water-cooled pc? | Generally superior cooling due to both heat absorption of liquid and a lack of stale warm air in the case.
Also quieter | [
"Liquid cooling is a highly effective method of removing excess heat, with the most common heat transfer fluid in desktop PCs being (distilled) water. The advantages of water cooling over air cooling include water's higher specific heat capacity and thermal conductivity.\n",
"Apple's Power Mac G5 was the first ma... |
why group mentality is so powerful | Human nature to belong and conform to social groups, empathy, and natural fear of exclusion.
It's kind of instinctual, that's why the weak minded are susceptible to group mentality. Case in point: Reddit. | [
"It has been thought that groups with the strong ability to work together will be able to solve dilemmas in a quicker and more efficient fashion than an individual. Groups have a greater amount of resources which lead them to be able to store and retrieve information more readily and come up with more alternative s... |
Are protons in nuclei wiggled by electrons "flying" around them? | This is better answered by answering each sub-question.
> Are protons in nuclei wiggled by electrons "flying" around them?
Yes, in the system both motions contribute to the actual state. But, the nucleus is very much heavier than the electron, so it's the electron that does most of the moving. Analogously, a swing with one heavy person and one light person moves so that the heavy person moves little. For most calculations it can be and is assumed that the nucleus is stationary.
As for other than electric force, not. A proton and an electron don't "collide" classically, which is a feature that now takes this scenario into quantum mechanics. Protons and electrons are different particles, so they don't occupy the same quantum state, and don't repel each other through the [exchange interaction](_URL_0_) like two electrons. So, when an electron flies headfirst into a nucleus, it will simply go through it like a ghost. This is exactly what happens with the *s* orbitals: [the nucleus has the highest electron density](_URL_1_).
This isn't as weird as you'd think. Consider a classical analogy: loose balls of yarn and double-pointed knitting needles. I think we can agree both are solid objects. Yet, you can pretty easily stick a needle right through a ball of yarn, even if you can't force another ball of yarn through.
> Protons and electrons attract each other.
Yes, but what is also necessary to understand that when an electron is accelerated, *there is nothing to stop it*. So, when it flies right at the nucleus, it will simply fly through and keep going, doing another loop on the other side. This system is stable over long times.
> And I hear that an electron is like wave around the nucleus. Waves oscillate so they should shake the proton.
Not really, in the dynamical sense you imagine. The reason quantum mechanics is called "quantum" is that there is the smallest possible quantum of energy, and only a restricted number of stable states. An electron forms a standing wave around the nucleus. In a similar way, the nucleus has its own mini-standing wave. The energy of this oscillation is very well-defined. In order to disturb it, you'd have to supply the full energy needed to raise it into a higher state. Smaller energies can't do much. | [
"In real molecules protons are surrounded by a cloud of charge due to adjacent bonds and atoms. In an applied magnetic field () electrons circulate and produce an induced field () which opposes the applied field. The effective field at the nucleus will be . The nucleus is said to be experiencing a diamagnetic shiel... |
how is the milk of a cow so beneficial to humans? | It's not just cows. Milk of many mammals is as beneficial to humans (and, on a side-note, that benefit *is* debatable, and many humans are, in fact, *not* able to process it).
Cows are just the animal we domesticated and started using for milk in a way that is ubiquitous in Western culture. In other cultures, other animal's milk is more widespread. That includes goats, camels, even donkeys. Also remember that much of Human population is lactose-intolerant. | [
"Although all mammals produce milk to nourish their young, the cow is predominantly used throughout the world to produce milk and milk products for human consumption. Other animals used to a lesser extent for this purpose include sheep, goats, camels, buffaloes, yaks, reindeer, horses and donkeys.\n",
"The female... |
Was the Indo-Aryan migration truth or fiction? | The Indo-Aryan migration is absolutely true, insofar as Indo-Aryan - a branch of the Indo-Iranian language family, which itself is a branch of the Indo-European family, which originated somewhere in the Pontic Steppe (around modern Ukraine, Crimea, and southern Russia) - is not indigenous to India. Anyone who claims that it was, including anyone who references the Indus Valley civilisation as an Indo-European one, is participating in nationalist pseudoscience. We know this from the method of [comparative reconstruction](_URL_3_), which shows that Proto-Indo-European, or the common ancestor to all Indo-European languages, had words relating to the material culture and natural environment of the Pontic steppe (for example, “salmon”, “birch tree”, and a whole host of words relating to horse domestication), but few or none indicating a culture that might have arisen in modern Pakistan (“elephant”, “lion”, and notably any words to do with the urban life that the Indus Valley people lived); those words were innovated or borrowed within Indo-Iranian or Indo-Aryan, and therefore don’t share any common ancestor with their equivalents in other Indo-European languages. With the addition of material archaeology, we can us the Indo-Europeans as being, or at least being related to, the [Yamnaya culture](_URL_1_), and thus certainly not related to the contemporaneous Indus Valley culture or any other culture of the Indian Subcontinent. This conclusively shows that the original speakers of Indo-Iranian, and thus their descendants the Indo-Aryans, migrated into Central Asia, then Iran and the Subcontinent at some point. The Indus Valley people, for their part, have been connected to the indigenous [Dravidian](_URL_0_) or (for a fringe hypothesis) [Munda](_URL_2_) peoples, but the relatively slim evidence doesn’t allow us to make a firm conclusion either or neither way; what’s certain is that originally, or at the time we generally associate them with, they weren’t Indo-Aryan.
The question that follows - and here the mainstream historical perspective differs from both the conflict-based Anglo-German colonial narrative *and* the unitarian Indian nationalist one - is what kind of migration this was: was it, as nineteenth- and early twentieth-century European historians generally assumed, a mass migration with violent conquest and population replacement, or a gradual, mostly-peaceful assimilation from a relatively small founding group based on trade and intermarriage? This is an important point, because the migration in general is a complex facet of human history - the Anglo-Saxon migration into Britain and the Slavic migration into Southeastern Europe are disputed along similar lines - and one we don’t have a complete answer to. Certainly it appears that the Indus Valley civilisation had a gradual but eventually total decline in the first half of the second millennium BC (from about 1900 to 1600), which coincides with the rise of the Indo-Aryan language family in the area. But whether the Indo-Aryan presence was a *cause* of the Indus Valley’s decline, or an *effect* of a decline caused by a more fundamental ecological or political collapse, is very much disputed. Modern history tends more toward the latter, as it does with the analogous but much later Anglo-Saxon and Slavic migrations, and some kind of synthesis between the two seems like the most plausible account of the period.
As for *why* Anglo-German historians preferred the idea of a violent migration over a gradual dispersal, the cause is not as fundamentally propagandistic as Indian nationalist historians assume; their arguments were based (for the most part) not in an effort to keep the various Indian peoples disunited and in conflict, but rather on a faulty scholarship that valued textual sources and those who produced them (i.e. the Vedas and Brahmins) over concerns of how, when, and why those texts were produced, leading to the impression of a united and distinct “Aryan” people - who supposedly neatly coincided with Brahmins themselves - opposed to a vague mass of *mleccha* indigenes. This, of course, was thoroughly amplified by the “scientific” racism of the time, and encouraged Anglo-German historians to interpret Indian history as one of Indo-Europeans (to whom they conveniently belonged) as a conquering people who subjugated the indigenous peoples of the Indian Subcontinent. The connection with race ideologies of the nineteenth and twentieth centuries is obvious, and still colours Indian history from both European and Indian perspectives to this day.
Overall, both the nationalist idea that the Indo-Aryan language family and early Hinduism were always indigenous to India and the Anglo-German colonial idea that Indo-Aryan represented a sudden and violent population shift are fundamentally discredited. The real answer lies not somewhere between the two, but through a subtler and more historically comprehensive understanding of “migration”.
A good layman’s source for the Indo-European migrations is David W. Anthony’s *The Horse, the Wheel, and Language*. Additionally, the [Wikipedia article](_URL_4_) on the Indo-Aryan migration is surprisingly and gratifyingly comprehensive, so I’d recommend it at least over the Internet. | [
"Some writers and archaeologists have opposed the notion of a migration of Indo-Aryans into India. Edwin Bryant and Laurie Patton used the term \"Indo-Aryan Controversy\" for an oversight of the Indo-Aryan Migration theory, and some of its opponents. These ideas are outside the academic mainstream. Mallory and Adam... |
If photons are smaller than atoms, why don't they pass through solid matter? | The closest thing to "size" for a photon is its wavelength. Different types of light have different wavelengths: x-rays have really short wavelengths, while radio waves have really long wavelengths. Visible light is somewhere in the middle.
If the wavelength is small compared to whatever we're dealing with, then you can treat the photon like a particle - i.e. it's a "bullet" that either hits, misses, or bounces off whatever we're dealing with. Visible light is 100s of nanometres in wavelength, which is way smaller than say, a window, and so you can think of it as a bunch of light "particles" flying towards the window: some of the particles go through the window, some bounce off the frame etc.
But if the wavelength is *big* compared to whatever we're dealing with, you really need to treat the photon like a wave - i.e. instead of a bullet being fired at a solid object, imagine a bunch of objects floating around in the ocean being shoved around by a water wave. This is the case for visible light and atoms. Visible light is 100s of nanometres in wavelength, but atoms can be even smaller than 1 nanometre. So you can't really "miss" with visible light - the photon passes through hundreds of atoms at the same time. This means there is definitely some interaction going on, and so the photon can be changed a little by the atoms, and that allows you to "see" the atoms when the photon hits your eye. | [
"Because the wavelength for even the smallest of macroscopic objects is extremely small, diffraction of matter waves is only visible for small particles, like electrons, neutrons, atoms and small molecules. The short wavelength of these matter waves makes them ideally suited to study the atomic crystal structure of... |
Did the concept of mutually assured destruction prevent the Cold War from going hot? | We really can't know the answer to complex hypotheticals like that. Smaller "What ifs" can sometimes be productive. But "what if the strategic situation of the world was totally different?" isn't something that historians can readily answer.
What they can do is point out that, 1) the Cold War was plenty "hot" if you lived in one of the places consumed by proxy war or state interference; 2) "mutually assured destruction" as a condition did not really apply until the 1960s, arguably the 1970s, because the Soviet Union's nuclear capabilities were far undermatched against the USA's, though the question of whether deterrence broadly (which is not the same thing as MAD) mattered is still up for grabs; and 3) there is evidence that there is more than nuclear deterrence that kept the Soviets from initially pressing westward in the 1940s, and there is clearly more than deterrence with the US lack of interest in engaging the Soviets militarily (or with nuclear arms) prior to the Soviets having a truly compelling nuclear force (e.g. before the mid-1950s if you care primarily about Europe, the 1960s or 1970s if you care more globally). The "nuclear taboo" — lack of use of nuclear weapons — has applied even in non-deterrent, definitely non-MAD, situations. | [
"In embryo, Waltz argues that the logic of mutually assured destruction (MAD) should work in all security environments, regardless of historical tensions or recent hostility. He sees the Cold War as the ultimate proof of MAD logicthe only occasion when enmity between two Great Powers did not result in military conf... |
How does pollution from mostly unregulated countries like China affect the rest of the world? | Long-range transport of air pollutants, including metals and pops, and is well-documented with ongoing research. While your last question seems mostly policy related, a large proportion of, but not all, nations decreasing use/production/emission of toxic chemicals does have significant effects in decreasing levels (sorry - turned your question around a bit).
The example I'm most familiar with is mercury - in its elemental form (Hg0), it forms a vapour and can be transported great distances. Ultimately, a lot of this winds up in the arctic, storing up over the winter and, upon polar sunrise, changing form (Hg2+), causing deposition, oral bioavailability, and toxicity. In recently chatting with a phd student working on mercury testing in arctic birds, she mentioned that mercury levels have begun to drop, although levels of other compounds either haven't/are increasing still. | [
"In recent decades, China has suffered from severe environmental deterioration and pollution. While regulations such as the 1979 Environmental Protection Law are fairly stringent, they are poorly enforced, as they are frequently disregarded by local communities and government officials in favor of rapid economic de... |
Do I weigh less at midday than at midnight? | A point of clarification: Mass is how much matter makes something up, so it won't change mass.
The position of the sun will change your weight, but only very, very slightly. It's only a very small fraction of the influence from the earth, so all other things being equal, there should be a very slight difference, something like less than a tenth of a percent.
_URL_0_ | [
"The terms \"heavy-weight\" and \"light-weight\" are often used to describe buildings with different thermal mass strategies, and affects the choice of numerical factors used in subsequent calculations to describe their thermal response to heating and cooling.\n",
"Weight lifting can effectively demonstrate the e... |
why does standing on a train tire me out? | It's the same thing as being in a car for an extended period of time.
While you aren't really making a lot of *big* movements, you are making a *very very large amount* of *tiny* movements. Every second you're adjusting, balancing, making sure things are going smoothly, watching all of the people, etc - so while you aren't physically doing a whole lot, your muscles are constantly contracting/relaxing, and your brain is constantly thinking. | [
"Prior to the accident, some passengers became concerned about their safety. Regular travellers were aware that the train was travelling at excessive speed and one who had moved from his seat to stand with friends in another carriage was forced to return to his seat as the movement of the train made it uncomfortabl... |
When a star collapses into a black hole, does the density of the singularity continue to increase forever? | It doesn't really make sense to consider the density of the singularity. You can consider the mean density of the entire black hole within the event horizon, which actually decreases as the black hole gets bigger. If you treat the center as a singularity, it has infinite density, like an electron has infinite charge density. | [
"One hypothesis is that the core of the star collapsed to form a black hole. The collapsing matter formed a burst of neutrinos that lowered the total mass of the star by a fraction of a percent. This caused a shock wave that blasted out the star's envelope to make it brighter. After the idea that a black holes are ... |
LEDs vs Normal Bulbs - Environmental Impact Outweighs Benefits? | I work with LEDs all the time. If you live in the US, the "Prius Conundrum" could be applied to any imported product.
As far as [luminous efficacy](_URL_5_), the LED lights that you can buy *right now* at Home Depot etc are about the same as compact fluorescent lighting (CFL). What's inside a white LED (blue LEDs are used with a phosphor) are some small amounts of semiconducting material, usually [indium gallium nitride](_URL_3_) that is completely encapsulated and not a heavy metal. Some [Philips LED lights](_URL_1_) (Home Depot has those for $15) use a remote phosphor that is completely encapsulated in plastic. (The blue LEDs inside them are about 45% electrically efficient)
LEDs will quickly over take CFLs in luminous efficacy and one can buy white LEDs now that are [significantly higher](_URL_0_) (+125 lumens per watt typical).
What they don't have are the shorter life spans of compact fluorescent bulbs, which reduces the the conundrum argument, and the small amounts of mercury they contain and some states have [specific laws on their disposal](_URL_4_).
_URL_2_ | [
"Objections to banning the use of incandescent light bulbs include the higher initial cost of alternatives and lower quality of light of fluorescent lamps. Some people have concerns about the health effects of fluorescent lamps. However, even though they contain mercury, the environmental performance of CFLs is muc... |
Is their a chemical or other additive(like what I do not know, perhaps one that reacts with water) that could make paint dry faster? | Many of the paints in use now take advantage of chemical driers or other systems to accelerate 'drying.'
Firstly, not all paints are water-based. In the case of oil-based paints, 'drying' is actually not related to the evaporation of water, but instead to the slow chemical reaction of the oil to oxygen in the air that gradually [polymerizes the oil into a film](_URL_0_). This is a slow process compared to, say, how fast watercolors dry. But, there are things ([like cobalt](_URL_2_)) that can be added to speed up the process. There are also other types of [oil-based products](_URL_1_) that have been chemically treated to 'dry' faster.
Water-based paints can be diluted with water-soluble volatile organic compounds (VOCs) that evaporate at a lower temperature than water, thus speeding drying, but this practice is generally frowned on (as it's never a good idea to inhale a lot of most chemicals). Most latex paints are water soluble (and, these days, low-VOC), so your best bet is to paint on a low-humidity day, open some windows and turn on some fans.
| [
"In recent years, water miscible oil paint has become available. Water-soluble paints are either engineered or an emulsifier has been added that allows them to be thinned with water rather than paint thinner, and allows, when sufficiently diluted, very fast drying times (1–3 days) when compared with traditional oil... |
When did the Byzantines stop wearing togas and other classical Greco-Roman garments? | They probably rarely wore togae in the first place. Togae were notoriously uncomfortable to wear, let alone in the stifling heat of the Eastern Roman Empire. Martial refers to work done during the day wearing the toga as 'toga work' (_opera togata_) and 'never ending' being such a pain. They would have official places, but according to Juvenal outside of Rome, everyone made do with more comfortable tunics or so forth instead - although the following is likely hyperbole, it reflects known attitudes towards the toga and its uncomfortableness.
> "There are many parts of Italy, to tell the truth, in which no man puts on a toga until he is dead. Even on days of festival, when a brave show is made in a theatre of turf, and when the well-known farce steps once more upon the boards; when the rustic babe on its mother's breast shrinks back affrighted at the gaping of the pallid masks, you will see stalls and populace all dressed alike, and the worshipful aediles content with white tunics as vesture for their high office. In Rome, everyone dresses above his means, and sometimes something more than what is enough is taken out of another man's pocket. This failing is universal here: we all live in a state of pretentious poverty.
(Juvenal, Satire 3).
See also; [Roman Dress and the Fabrics of Roman Culture, edited by Jonathan Edmondson and Alison Keith](_URL_0_) | [
"The Byzantines made and exported very richly patterned cloth, woven and embroidered for the upper classes, and resist-dyed and printed for the lower. By Justinian's time the Roman toga had been replaced by the tunica, or long \"chiton\", for both sexes, over which the upper classes wore various other garments, lik... |
Was it commonplace for Royals of old to be highly learned and respected in Academia? | It was generally not common. Certainly there were some monarchs who did have some scholarly abilities. Queen Elizabeth I translated Boethius's Consolation of Philosophy.
But the amount of training in languages and literature necessary to be a truly accomplished scholar was tough for a monarch to achieve. They tended to be more patrons of scholarship (like Charlemagne or Alfred the Great or Catherine the Great) than scholars themselves. | [
"Later, in the Georgian and Victorian eras, royal education followed the French model, with governors overseeing the child's discipline and moral development, and preceptors conducting academic instruction. In the modern era, members of the House of Windsor have had varying degrees of education. The first heir to t... |
why is gold so expensive? | _URL_0_
> Gold emerged as a sort of inevitable global currency, before people even thought of it as currency. It is rare, portable, easy to identify, can easily be made into jewelry, and can be easily quantified (unlike, say, jewels or seashells, which are harder to treat as a "substance"). Once word got around that rich people like it, it became easy to barter with anyone, anywhere, for anything.
> In the early stages, it was not really the same thing as "money", it was just an easy thing to barter. But it had money-like characteristics:
> - If someone walked into your apple-orchard offering to trade a yellow rock for apples, you might look at them a little funny. What use does an apple-grower have for a yellow rock?
> - But if you know that rich people in town covet this soft yellow metal as something they can make jewelry out of, then you might be happy to trade apples for it.
> - Once *everyone* knows that rich people will trade for this stuff, it becomes something like actual currency: neither the hunter, the shoemaker, nor the fisherman in town has much use for it, but because they know they can redeem it for the stuff they *do* want and need, it becomes a sort of transferable IOU that can be redeemed anywhere, i.e., money.
| [
"Gold has been used as money for many reasons. It is fungible, with a low spread between the prices to buy and sell. Gold is also easily transportable, as it has a high value to weight ratio, compared to other commodities, such as silver. Gold can be re-coined, divided into smaller units, or re-melted into larger u... |
how do options and shorts work for investments? | For shorts, its better to think about what you're expecting to happen when you do it than how its actually executed in the market (which is more complicated, but ultimately unimportant to you, the trader).
When you buy a stock, the *only* reason to buy it is that in the future you expect it to be higher than when you bought it. This is being "long".
When you short a stock, the *only* reason you "buy" it is that you think the stock will be lower in the future.
Your broker doesn't give a shit what you trade, they just facilitate the trade and take a commission (this is a bit untrue, but for these purpose its fine). When you short a stock, you potentially have a chance to lose more money than you have though, so they require these accounts to have some extra money to cover the losses in case that happens. | [
"This type of option is best used when the investor would like to generate income off a long position while the market is moving sideways. It allows an investor/writer to continue a buy-and-hold strategy to make money off a stock which is currently inactive in gains. The investor/writer must correctly guess that th... |
Why is tungsten at room temperature so brittle? Since super cooled metals are more brittle, is this the same phenomenon but just at a much lower temperature because tungstens melting point is so high? Or is it something entirely different? | Basic answer is that tungsten is Body Centered Cubic (BCC) and therefore will go through a ductile to brittle transformation at certain temperatures. DBTT (Ductile to Brittle Transition Temperature) of tungsten is quite high, around 400K. Room temperature, or 273K, is way below this transition temperature, so the tungsten will be brittle.
The basic mechanics here is that below this temperature there isn't enough vibrational energy in the lattice to allow for slip. So the atoms are almost locked in place and are unable to slide past each other, therefore they will separate and the material will fracture. | [
"Of all metals in pure form, tungsten has the highest melting point (3422 °C, 6192 °F), lowest vapor pressure (at temperatures above 1650 °C, 3000 °F), and the highest tensile strength. Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so... |
can someone explain to me the pros and cons of capitalism? | Capitalism: An economic system under which capital is controlled by private individuals.
Capital: Productive property such as factories, farms, financial institutions, or other systems which create wealth.
Pros: In theory, it allocates capital to the areas in society where they are most useful. For instance, let's suppose Mr. White, Mr. Green, and Ms. Brown all own factories making T-Shirts. Ms. Brown finds a cheaper way to put the design on T-shirts, thus, she can make more of them while spending less money. Because she's spending less money, she is able to expand the factory, so more T-Shirts will be made in the more efficient way, benefiting society.
Cons: A lot of the money that goes to capitalists doesn't make its way down to the rest of society, and ends up not benefiting society in any particular way. For instance, after a few months or two, Ms. Brown is making enough money that she not only expands her factory, but also buys Mr. White's factory. Now she's making twice as much money (even though she isn't doing twice as much work as she was before). Now, most of her money is going to pay for luxuries and more capital. This isn't benefiting society, since it's silly to produce extravagant luxuries for the few when there are still people struggling to get things they need. Furthermore, Mr. Green has long since adopted the new way of making T-Shirts, so it no longer really benefits society that Ms. Brown is expanding her factories, because factories owned by her are no longer any more efficient than factories owned by anyone else. In fact, Ms. Brown doesn't even manage most of the factories anymore; she pays other people to do that. So in the end, the only one who has benefited from Ms. Brown having so much capital is Ms. Brown herself. | [
"A closely related conception is that of raw or pure capitalism, or unrestrained capitalism, that refers to capitalism free of social regulations, with low, minimal or no government and operating almost entirely on the profit motive. Other than \"laissez-faire\" economics and anarcho-capitalism, it is not associate... |
What is the final form of energy? | Heat (thermal energy) would be the closest to the answer you are looking for.
_URL_0_ | [
"In biology, energy is an attribute of all biological systems from the biosphere to the smallest living organism. Within an organism it is responsible for growth and development of a biological cell or an organelle of a biological organism. Energy is thus often said to be stored by cells in the structures of molecu... |
how does apple own the beatles? | [The Beatles sold the rights to their catalog of music back in the 1960s.](_URL_1_) It's been owned by many people, most famously by Michael Jackson, who made almost as much money on Beatles royalties as on his own music.
I don't know if Apple Computer has any ownership in Beatles music, but you might be confused by [Apple Records](_URL_0_). Long before Steve Jobs was in business, The Beatles named their record company Apple. There was actually [a lawsuit between the computer company and the record label, because of conflicting trademarks.](_URL_2_) | [
"After Klein's departure, Apple was managed by Neil Aspinall on behalf of the four Beatles and their heirs. Apple Records' distribution contract with EMI expired in 1976, when control of the Beatles' catalogue—including solo recordings to date by George Harrison, John Lennon and Ringo Starr—reverted to EMI (Paul Mc... |
if in the vacuum of space there are no exterior forces acing on a spacecraft, why can't we continuously speed up the craft to light speed with constant thrust? | It takes more and more energy to constantly accelerate a spacecraft. This means that as you approach C the amount of energy that you need to go faster approaches infinity. Sadly humans do not have access to infinite energy so we can never actually reach C. | [
"A related issue is drag. If the near light-speed space craft is interacting with matter or energy that is moving slowly in the planetary reference frame—solar wind, magnetic fields, cosmic microwave background radiation—this will cause drag which will bleed off a portion of the engine's acceleration.\n",
"Ion th... |
Hebrew language revival | It was about the national identity, not religious reasons. More religious segments of Judaism were historically (and often still are) skeptical of Zionism in general, of which the Hebrew revival was a part.
First, some linguistic background. Hebrew went extinct by the 2nd century. But it remained in use in Jewish communities as the language of the liturgy, Jewish texts, and religious literature. Synagogues still generally used Hebrew biblical texts, religious learners still learned Jewish texts, Rabbis still wrote Hebrew commentaries. Jews were generally literate in Hebrew script, and used it for writing non-Hebrew languages in many cases.
The revival of Hebrew is an interesting linguistic topic. The father of Hebrew is Eliezer Ben-Yehudah. But the process began a bit before. During the 19th century, the Jewish literary revival involved making Jewish works of "high" literature, in both Hebrew and Yiddish. One product of this was a body of literature in Eastern Yiddish (Tevye the Milkman was a product of this, which of course became Fiddler on the Roof). Another was new literary writing in Hebrew, by authors like Chayim Nachman Bialik.
It's with this backdrop that we get a critically important, but sadly forgotten, Zionist named Ahad Ha'am (that was his penname--his actual name was Asher Grinsberg. Ahad Ha'am means "one of the nation"). There were several strands of Zionism in the late 19th century. His was sometimes called "cultural Zionism". He saw the establishment of a Jewish state as the ultimate expression of this Jewish cultural revival. Just as writing literature would revitalize Jewish writing, a Jewish state would revitalize all aspects of Jewish life. He saw Zionists like Herzl as being sort of half-assed. They wanted to help Jews, yes, but they didn't want to really make Jews a more vibrant nation. In essence, he saw Herzl et al as trying to create a "state of Jews", while he wanted a Jewish state. He didn't think it was practical to just get Jews to migrate to Palestine--you'd need a cultural revival to get people interested in such a national enterprise
And he wrote these objections in Hebrew. One of his bigger essays, זה לא דרך (Hebrew for "this is not the way"), where he outlined his objections. Trying to build a state out of nothing is pointless--first, Jews have to be inspired by a revitalization of Jewish culture.
Around this time Eliezer Ben-Yehudah started working to revive Hebrew. He did a few things to this end. He wrote a Hebrew-language newspaper based in Jerusalem. He raised his son as a native monolingual Hebrew speaker. He wrote a Hebrew dictionary, including a number of coined words for new concepts.
To address your initial question, there were religious objections to this. Hebrew was, in Jewish parlance, *lashon kodesh/loshn koshesh*, the Holy Tongue. It had a religious significance. And many objected to its use in daily affairs. It was a particular point of controversy for Eliezer Ben-Yehudah in Jerusalem, which had a large religious population.
With this intellectual and ideological backing, combined with someone doing the legwork, Hebrew slowly started to gain ground. In the early 1900s Zionists incorporated Revisionist Zionist lingo into the language arguement. They saw Yiddish as an exilic language, which was to be eschewed for the *real* Jewish language, Hebrew. This active objection to other languages, combined with the ideological advantage of a Jewish revival it provided, gave it strength.
Perhaps the solidifying moment was in the establishment of the Technion. It's a scientific univerisity in Haifa. There were intense debates about what its language should be. On one hand, German was the language of scientific discourse at the time. On the other, it was a institution in the Jewish statehood enterprise, and it should use the Jewish language. Eventually, Hebrew won out.
So propelled by a couple pieces of Zionist ideology, Hebrew managed to become the language of what would become Israel.
Edited to remove typo | [
"The revival of the Hebrew language in Israel is the only example of a language's acquiring new first language speakers after it became extinct in everyday use for an extended period, being used only as a liturgical language. Even in the case of Hebrew, there is a theory that argues that \"the Hebrew revivalists wh... |
What was the source of gunpowder for the colonial militias during the American Revolution? | The American colonists had very limited supplies of gunpowder and very limited capacity for manufacturing more of it (precise figures are in the link.) Had there not been a foreign source of gunpowder it is very doubtful that they could have been successful in their revolution. Who was this crucial benefactor? [Why the liberty loving King of France Louis XVI.](_URL_1_)
It's easy to forget that North America remained a side theater to European conflicts. Without France's self interested support there couldn't have been American independence.
[Here's another link with more detailed figures]( _URL_0_) | [
"Prior to the American Revolutionary War very little gunpowder had been made in the colonies, and most was imported from Britain. In October 1777, the British Parliament banned the importation of gunpowder into the American colonies. In preparation for the overmountain march, five hundred pounds of black powder was... |
when cops and dea agents perform undercover drugs busts where do they obtain said drugs? | I think most of the time they act as the buyers, not the sellers. They are trying to work their way UP the ladder, not down, so they want the dealers, not the end users.
So they just make multiple buys from a small dealer, then bust him, and try to flip him to be a double agent in exchange for less jail time. Then they try to get him to introduce them to the next step up the ladder and do some bigger buys from him, then bust him and try to flip him also.
Then they just repeat this process as high as they can go, but the higher they go and the less productive the undercover operation is, as it takes much longer to gain trust, and get to the real kingpin instead of one of his flunkies or lieutenants, plus the buy quantity needs to keep escalating and it's hard to tell your boss down at the cop station, "Hey, I need a million bucks to buy some drugs" so there is really only so high they can go before it becomes completely unproductive. | [
"A narcotics agent convinces a convict he helped send to Alcatraz go undercover with him to help expose a heroin drug smuggling ring. The unlikely pair travels from San Francisco to Vancouver and finally to a dude ranch in Tucson which is run by mob bosses. They end up getting help breaking the case from the gang l... |
what happens to clothing that isn't sold? | What you're asking about is the retail chain. For most products, it works like this:
Manufacturer makes a product, and markets it to retailers, who place orders in various quantities. They ship the orders, and the retailers sell it in line with their contract with the manufacturer. Using your example, Levi doesn't want to compete with itself or have the price fall so low it causes perceived value issues, so they may have a minimum price the jeans can be sold for.
After a certain point, the unsold merchandise will go through a series of price reductions via sales, promotions, bogos, and ultimately end up on clearance.
The merchandise remaining after the clearance sale will be sent to the retailers distribution centers and bundled into lots. These lots are sold to discount outlets. For clothes, that would be places like Marshall's, Kohl's, TJ Maxx, etc.
They go through the same price reduction process as before, only becoming cheaper still. These places do hold on to merchandise for a considerable amount of time. You can find some relics at Big Lots, for example.
If the merchandise is still sitting unsold, it often ends up being put back in lots and re-auctioned to the bottom feeders of the retail chain - flea marketeers, eBay and Amazon wanna be moguls, etc.
At that point, the merchandise that doesn't sell is either so severely discounted, you are literally only paying for the shipping and storage, or it is finally liquidated via donation for tax purposes.
Or, you fill a warehouse with it, wait a respectable amount of time, and light a match. | [
"Clothing has been made from a very wide variety of materials, ranging from leather and furs to woven fabrics to elaborate and exotic natural and synthetic fabrics. Not all body coverings are regarded as clothing. Articles carried rather than worn (such as purses), worn on a single part of the body and easily remov... |
how is a single injection of a drug able to provide months of therapy? | Esterification of an injectable steroid basically accomplishes one thing, it slows the release of the parent steroid from the site of injection.
This happens because the ester will notably lower the water solubility of the steroid, and increase its lipid (fat) solubility. This will cause the drug to form a deposit in the muscle tissue, from which it will slowly enter into circulation as it is picked up in small quantities by the blood. Generally, the longer the ester chain, the lower the water solubility of the compound, and the longer it will take to for the full dosage to reach general circulation. | [
"Alternatively, a single-dose therapy is used for instance if there are concerns regarding the patient's compliance. The single-dose therapy can be given as an injection, but is normally given in form of an oral medication.\n",
"Infusion therapy involves the administration of medication through a needle or cathet... |
How does amputation early in life affect growth of the amputated limb? | Typically amputated limbs do not grow. | [
"If extensive necrosis and gangrene has set in an arm or leg, the limb may have to be amputated. Limb amputation is in itself usually remarkably well tolerated, but is associated with a substantial mortality (~50%), primarily because of the severity of the diseases in patients where it is indicated.\n",
"As many ... |
Were legendary swords actually a thing? | Heya guys, just popping in here to issue a quick reminder as to the [standards we uphold in this subreddit.](_URL_0_) Not a single one of the answers so far has measured up to those standards, including posts along the lines of:
* "I don't know a great deal about this but as there are no other replies I'll have a go"
* "This one (Wiki link)"
* "Link to Youtube 'popumentary'" (We've had 6 or 7 different posts linking to the Ulfbehrt video, which is about as far from academic as you can get.)
Also, please remember the three things to ask yourself before posting:
1. Do I, personally, actually know a lot about the subject at hand?
2. Am I essentially certain that what I know about it is true?
3. Am I prepared to go into real detail about this?
If any one of these is answered with a "no," then please think twice about posting.
Thanks so much for your consideration! :) | [
"Various famous swords may be encountered Chinese legend or mythology. Some of these swords also appear in literary fiction; or, various other media, including comics and video games. There are two main types of sword: \"jian\" and \"dao\". Swords with estimated or presumed magical powers (or, that were especially ... |
how quartz crystal resonators work? | They rely on a piezo crystal. These crystals have the useful property that they generate a voltage if you squeeze them, and expand or contract if you apply a voltage. They are commonly used in lighters (squeezing them generates a high voltage, which causes a spark), speakers and ultra sound transducers(a rapidly oscillating voltage contracts and expands the crystal) and kitchen scales (putting a weight on them generates a voltage).
As a resonator, the crystal is tuned like a musical instrument to oscillate at a certain frequency, and combined with a small amplifying circuit. If you turn it on, it starts oscillating at a precise frequency, and never stops. Imagine it like a tuning fork, only that it never stops humming as long as you apply a voltage. | [
"A crystal oscillator is an electronic oscillator circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a precise frequency. This frequency is often used to keep track of time, as in quartz wristwatches, to provide a stable clock signal for d... |
What are the best examples of forgiveness and philanthropy and self-sacrifice from history? | Sorry, we don't allow ["example seeking" questions](_URL_1_). It's not that your question was bad; it's that these kinds of questions tend to produce threads that are collections of disjointed, partial, inadequate responses. If you have a question about a specific historical event, period, or person, feel free to rewrite your question and submit it again. If you don't want to rewrite it, you might try submitting it to /r/history, /r/askhistory, or /r/tellmeafact.
For further explanation of the rule, feel free to consult [this META thread](_URL_0_). | [
"Forgiveness as a tool has been extensively used in restorative justice programs, after the abolition of apartheid Truth and Reconciliation Commission (South Africa), run for victims and perpetrators of Rwandan genocide, the violence in Israeli–Palestinian conflict, and Northern Ireland conflict, which has also bee... |
how does the 100 year old light bulb work? | It's actually nowhere near as exceptional as you think. A huge proportion of the wear on light bulb filaments is to to thermal expansion and contraction from being turned on/off (this is why bulbs only ever to fail when you first turn them on). These very old bulbs are bulbs that have been left on continuously, so they don't get that wear: they just sit there, at a steady temperature, not being stressed in any way, so they don't fail. | [
"The Centennial Light is the world's longest-lasting light bulb, burning since 1901, and almost never switched off. It is at 4550 East Avenue, Livermore, California, and maintained by the Livermore-Pleasanton Fire Department. Due to its longevity, the bulb has been noted by \"The Guinness Book of World Records\", \... |
Why aren't you still contagious after you recover from a viral infection? | It is absolutely not true that viruses remain in your body forever. There are a small subset of viruses that do that, but the vast, vast majority of viruses are completely eliminated from your body by the immune system. | [
"A latent infection may become productive in response to changes in the host's environmental conditions or health; the provirus may be activated and begin transcription of its viral genome. This can result in the destruction of its host cell because the cell's protein synthesis machinery is hijacked to produce more... |
Are there any magnets available commercially that will adhere to aluminum? | Magnetic effects generally arise from the interactions of unpaired electrons. Typically, magnetic materials (such as iron) are ferromagnets, which means that the the unpaired electrons the d-orbitals can spin-align under certain conditions. Aluminum only has s and p orbitals, and therefore no d electrons are available for spin alignment. Therefore, aluminum exhibits no intrinsic ferromagnetism.
However, there are other means by which aluminum may magnetically interact. For instance, if one passes a current through an aluminum object, it will give off a weak magnetic field (Lenz's law), which will cause the aluminum to interact with a magnet. Other effects related to Lenz's law and electromagnetic flux may also cause aluminum to weakly interact with magnets (_URL_0_). So, in principle, one could apply a current to a piece of aluminum, and achieve a magnetic interaction with any commercially available magnet. | [
"The most suitable materials for magnet wire applications are unalloyed pure metals, particularly copper. When factors such as chemical, physical, and mechanical property requirements are considered, copper is considered the first choice conductor for magnet wire.\n",
"Ceramic, or ferrite, magnets are made of a s... |
how does a fast charging plug charge faster when the socket has the same output when there's a regular plug? | The "fast charge" socket **does not** have the same output.
The voltage is the same, but the current available at that voltage is higher. This must be taken into account when choosing cables and connectors. | [
"Note that the less resistance there is between the capacitor and the charging power supply, the faster it will charge. Thus, in this design, those closer to the power supply will charge quicker than those farther away. If the generator is allowed to charge long enough, all capacitors will attain the same voltage.\... |
Generating electricity and rotating magnets | You could, but it wouldn't be beneficial. Any energy being used to cause rotation of the smaller magnets is not going in to generating electricity. You could be better off using your super magnet to generate electricity directly. | [
"Electric generators transform kinetic energy into electricity. This is the most used form for generating electricity and is based on Faraday's law. It can be seen experimentally by rotating a magnet within closed loops of conducting material (e.g. copper wire). Almost all commercial electrical generation is done u... |
In John Milton's Paradise Lost, Satan is sometimes read as the protagonist. While Milton obviously didn't intend this, did any of his contemporaries believe this? | [Yes.](_URL_0_)
As the source describes, Milton was a republican in the historical sense. It was during his lifetime that Oliver Cromwell, still a divisive figure in English history, rose to power after overthrowing Charles I. Milton supported this. Charles I was deposed, but after returning and making war throughout the 1640s, the English ultimately executed him in 1649. Following this, Cromwell is given the title of Lord Protector of the realm, although after his death, the monarchy is restored bloodlessly. Although Richard Cromwell was selected to succeed, he did not command the requisite respect and was booted out of office within a year, leading to the restoration of Charles II to the throne.
Fast forwarding to 1667, after Milton (unpopular for his Republican views, at this point blind, which was considered by some to be divine punishment for his support of regicide, or the killing of the king.)
> England in 1667 was reeling from the events of the previous year, when plague and fire had swept the capital, causing a devastation many people thought was divinely inspired; a biblical epic from a blind, grim old controversialist was by no means certain of being sympathetically received, as the poet's wish that his poem might 'fit audience find, though few' (VII.31) perhaps recognises. In spite of this unwelcoming climate, when Paradise Lost appeared, it was hailed as a work of genius, even by Milton's political opponents.
One of the first adaptations of the poem is John Dryden's play, which "outsold the original until the end of the seventeenth century."
> Satan, who disdains servitude and tries to overturn his monarch, becomes in Dryden's rewriting an unmistakeable portrait of Oliver Cromwell, the king-killer. He also believed that the fallen angel, and not Adam, was the hero (in the sense of his structural position as the protagonist of the epic), and weighted his adaptation accordingly... Contemporary readers who thought there was a whiff of sulphur about the unrepentant republican poet were not surprised to find these sentiments in the mouth of the arch-fiend; and there were those who believed that Milton was in fact disowning his previous stance by associating it with Satan. Neither reading does justice to the complexity of Paradise Lost, but this does identify what was to become a recurrent theme in later responses to the poem: the contested interpretation of Satan, its eloquent anti-hero.
The most prominent later commenter on Milton who views Satan as the protagonist, William Blake, remarks that, "The reason Milton wrote in fetters when he wrote of Angels and God, and at liberty when of Devils and Hell, is because he was a true Poet and of the Devil's party without knowing it."
Essentially, opinions are divided: as the linked source would indicate, many at the time may have viewed Milton's poem as autobiographical in a sense, or as they say, that Milton was "disowning his previous stance by associating it with Satan." Those who favored Cromwell were likely to favor it; even those who didn't agree with Milton like his political opponents "hailed [it] as a work of genius." The role of Satan, then as now, was open to interpretation and disputation.
Source:
Peter Gaunt, *Oliver Cromwell* | [
"John Milton's epic poem \"Paradise Lost\" features Satan as its main protagonist. Milton portrays Satan as a tragic antihero destroyed by his own hubris. The poem, which draws extensive inspiration from Greek tragedy, recreates Satan as a complex literary character, who dares to rebel against the \"tyranny\" of Go... |
after their extinction, why did dinosaur type creatures not evolve all over again? | The ecological niches formerly occupied by dinosaurs were taken over by the creatures that survived the mass extinction. So now instead of big dinosaur carnivores like t-rex, we have big mammalian carnivores like lions, tigers, polar bears, killer whales, and fish like great white and bull sharks.
If all mammals became extinct tomorrow, but amphibians survived, hundreds of millions of years from now there would probably be big amphibian carnivores and big herbivores. | [
"After yet another, the most severe extinction of the period (251~250 Ma), around 230 Ma, dinosaurs split off from their reptilian ancestors. The Triassic–Jurassic extinction event at 200 Ma spared many of the dinosaurs, and they soon became dominant among the vertebrates. Though some mammalian lines began to separ... |
I know of absolute zero at -273.15°C, but is there an absolute hot? | We don't know if there's a maximum temperature.
In certain models -- string theory is one of them -- there is a maximum temperature called the *Hagedorn temperature*. This arises because the number of possible high energy states increases sufficiently fast that as you put more energy into the system, it gets spread out over more and more states in such a way that the temperature decreases less and less for a given amount of heat put in. Net result is that there's a temperature that is the upper limit of the temperatures that can be reached.
I'll add that even in string theory, some people think the Hagedorn temperature might not be an actual limit, but more an indication that there is a phase transition (like when a liquid turns to gas), but that's even more speculative. | [
"BULLET::::- In January 2013, physicist Ulrich Schneider of the University of Munich in Germany reported to have achieved temperatures formally below absolute zero (\"negative temperature\") in gases. The gas is artificially forced out of equilibrium into a high potential energy state, which is however cold. When i... |
programming and writing computer code (if it can be explained to a 5 year old) elim | If you have a lot of time, I think a wonderful and engaging introduction is Harvard's [CS50](_URL_0_) course, and it leads you step-by-step through many of the questions you have. | [
"BULLET::::- May 1 – At 4:00 a.m., John George Kemeny and Thomas Eugene Kurtz run the first computer program written in BASIC (Beginners' All-purpose Symbolic Instruction Code), an easy to learn high level programming language which they have created. BASIC is eventually included on many computers and even some gam... |
how can google get fined by eu for practically promoting their own products/brand(google search engine & android/google search engine on android devices) | How can they? The EU can impose a fine and refuse to let them operate in the EU until it is paid.
Why would they? Because it can be considered a breach in monopoly laws. Microsoft was indicted on the grounds of monopolization for bundling internet explorer with their OS.
I may be a bit out of the loop but are you asking about what rule they might break or what rule they did break? | [
"On 19 July 2018, EU has fined Google (about ). Google responded it would appeal the fine, which it did in October 2018. According to company spokesperson Al Verney \"Android has created more choice for everyone, not less\". To date, this fine is the biggest ever imposed by European Union on a company for anti-comp... |
What was US espionage like from the Revolutionary War period through the Civil War? What sort of information was targeted and how was it collected? | In the intelligence community Nathan Hale is often called "America's first spy". He was captured by the British in 1776 and executed, famously stating "I only regret that I have but one life to lose for my country."
Hale's mission was to go behind the British lines and report on their movements.
This was the same for almost all human intelligence (HUMINT) gathering in those days. When battles were fought in formations the most valuable piece of information was at what point the formation would be weakest so that it can be penetrated/flanked/or used to flank. When the force was too large to fight, it allowed units to avoid engagement or retreat and re-engage under more favorable conditions.
More famous "spies" during the Civil War weren't actually conducting espionage as much as sabotage. The Great Locomotive Chase as an example, for which the first Medal of Honor was awarded. These men were executed as spies regardless.
Information of simple troop movements back in those days sounds useless with all the things the US intelligence community can do nowadays, but don't discredit its value.
General Beauregard of the Confederacy credits a spy from Virginia for the victory at First Manassas (First Bull Run). This spy was Bettie Duvall, and she rode from Washington to Fairfax to pass on those troop movements. Individual spies, same as scouts, could move much faster than entire units. However, scouts were uniformed and watched carefully. Spies were not uniformed and integrated themselves into local life. This was the advantage of a spy.
Mostly, the spies were just eyes. They went into an environment, kept an eye on things, and reported anything deemed valuable enough. None of this was centralized.
Allen Pinkerton made the first attempt at centralizing intelligence. He built a counterintelligence (CI) network in Washington to counter Confederate HUMINT. He built up his own HUMINT operation in Richmond to keep eyes and ears open. However, its effectiveness is questionable. Pinkerton's intel was often bad and cost a few battles by convincing the commanders not to attack a force they thought was stronger, but wasn't.
**TL;DR + Conclusion** - It was mostly a de-centralized network of eyes and ears in public. The targeted information was primarily troop movements, though other information like important infrastructure, routes, goals, and unit readiness were also valuable. | [
"American Intelligence in the American Revolutionary War was essentially monitored and sanctioned by the Continental Congress to provide military intelligence to the Continental Army to aid them in fighting the British during the American Revolutionary War. Congress created a Secret Committee for domestic intellige... |
computer shellcode (shell code) | If you're not a programmer, the only thing you can really do is make sure that you consistently update your software, especially when it says it's for security reasons.
If you are a programmer, you should be aware that one of the most common types of security vulnerability is a buffer overflow. What this means is that if your program is not properly checking the length of data inputted by the user, the user can write past the boundary you have allocated for that particular data and overwrite different parts of memory. This becomes an issue when the user overwrites the code segment of memory, which tells the computer which instructions to execute. If a malicious user overwrites this area of memory with his own instructions, they can be executed instead. Commonly, a user will overwrite it with "shell code," which is code designed to spawn a shell. A shell is basically the command line interface by which you can control your computer (cmd most closely resembles this in Windows). | [
"In hacking, a shellcode is a small piece of code used as the payload in the exploitation of a software vulnerability. It is called \"shellcode\" because it typically starts a command shell from which the attacker can control the compromised machine, but any piece of code that performs a similar task can be called ... |
How does a king or queen end up with a epithet...such as Alfred the Great, Æthelred the Unready, Edward the Confessor, etc? | A couple ways.
1. They give it to themselves. *Every* Joseon Korean King styled himself "the Great"
2. Others give it to them. Kings in Europe took their epithets personally and knew what they were in many cases. They all wanted a name like "the Bold", "the Good", "the Brave", or "the Great", or in rare cases "the Lionheart". Richard probably got a little woody when he heard the last one for the first time. It became standard practice for courtiers to assign such names and for even ordinary people to come up with ways to describe their King. Lots of them were neutral, like "Barbarossa" (Red Beard). Others, like "the Thunderbolt", referring to Bayezid of the Ottomans, were very accurate and referred to specific events, like Bayezid's racing his army between Europe and Asia.
3. The state officially assigned names to monarchs and minted them on coins. Islamic countries did this a lot, with every Ottoman Sultan styling himself "Gazi" or some positive epithet.
4. Historians and literati ascribe epithets after the reign of the monarch. No doubt very few would dare call Ethelred "the Unready" during his reign. That was an epithet made popular by later historians of England writing about their own country. The same case was for Timur the Lame, who in his day was called Timur the Great.
Usually it starts with courtiers or literati genuinely praising a King or coming up with a witty, ironic epithet like "the Confessor". Then, it either catches on with contemporaries at the time, or with later writers. | [
"In some contemporary as well as later sources, Ælfric (a common Old English name) is distinguished by his cognomen \"Cild\". Literally meaning \"child\", it is an Old English title borne by some Anglo-Saxon nobles and typically denotes a man of high rank. Ælfric appears to have been a wealthy landowner in Huntingd... |
Why do English translations of WWII German always leave the words "Reich" and "Führer" in German? | These words have entered the consciousness of English-speakers (and speakers of other languages) as having a specific connection to a certain object. There are dozens of German leaders, there is only one Fuhrer. This is the same with, say, Czar or Chief.
Similarly, sometimes words get extra meanings that are lost in translating. A South American Caudillo isn't just a "war leader" or "head", but a Caudillo. | [
"The word \"Führer\" in the sense of \"guide\" remains common in German, and it is used in numerous compound words such as \"Oppositionsführer\" (Leader of the Opposition). However, because of its strong association with Hitler, the isolated word usually has negative connotations when used with the meaning of \"lea... |
how far ahead we are in achieving unified field theory ? | Not very far unfortunately. Without going into the details (which I'd be crap at explaining anyway), string theory seems to be the most promising avenue. However, there seem to be virtually an infinite number of configurations of the math that leads to a consistent universe which makes it practically impossible to find the right equations that would give us the conditions for our universe. Without the math it's extremely hard to come up with experiments that would test the theory. There's also the problem of the theory being based on sizes near the Planck scale which are currently impossible for us to see. A few experiments or potential observations have been proposed which could provide evidence based on current or near future technology, but so far none have yielded any evidence.
There's also the problem that so far there is no experiment or observation proposed which could disprove the theory. For a scientific theory to even be considered a scientific theory, this is one of the most important features. (I.E. relativity could be disproved by there being no time dilation observed by clocks or observing something moving faster than light speed.) String theory so far has nothing like this after a couple of decades, and there has been debate about whether or not it should even be considered a scientific theory.
There are a couple of other possibilities being floated around, but so far they have yet to yield any results more promising than string theory. | [
"Presently, effective field theories are discussed in the context of the renormalization group (RG) where the process of \"integrating out\" short distance degrees of freedom is made systematic. Although this method is not sufficiently concrete to allow the actual construction of effective field theories, the gross... |
Were there ground public transportation options before the advent of the automobile and the locomotive? | One of the best known ground public transport options was stage coaches, so-called because they regularly changed horses with each stretch between changes being called a "stage". In Australia the best known and remembered of these is "Cobb & Co" although there were many other companies running coaches.
_URL_0_ | [
"The proposed Liverpool and Manchester Railway was to be one of the earliest land-based public transport systems not using animal traction power. Before then, public railways had been horse-drawn, including the Lake Lock Rail Road (1796), Surrey Iron Railway (1801) and the Oystermouth Railway near Swansea (1807).\n... |
how do generic brands work and why are they cheaper than their name brand cournterparts? | Typically the main difference is the amount of marketing the company puts in. Large brands put in millions of dollars into marketing while off brand counterparts usually advertise not at all. Sometimes they may even made in the same place as brand name products but it comes down to the advertising costs. | [
"Branded products carried include HARIBO in Germany, Knoppers in Belgium and France, Marmite and Branston Pickle in Great Britain; and Vegemite and Milo in Australia. This is usually very strongly branded items, that in the past they have had difficulty in creating a generic version of the product. In the United St... |
what is a runny nose supposed to accomplish? it seems so counterproductive | Your "internal snot chutes" empty into the stomach. The snot, along with anything that happens to get stuck in it, gets destroyed by stomach acid. So sniffing it back in, and then down into your throat, is the entire point. | [
"Mucophagy, despite its benefits on one's immunity, comes with some health risks due to the potential physical aggravation resulting from the action of nose picking, and the germs on fingers and in mucus. Picking one's nose can cause upper airway irritation as well as other injuries including nasal septal perforati... |
how can we know the size of the observable universe of we only just escaped the solar system? | _URL_0_
light travels fast, but not infinitely fast. a very short time after the big bang light was first able to travel in straight lines relatively unobstructed. we can only see as far away from our vantage point as the light gets to us.
so if the universe is 13 billion years old, you would only expect to be able to see a sphere around us with about a 13 billion light year radius. That is simple way to think about the observable universe.
but the universe is still expanding, so it is a little more larger and more complicated than that, too.
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"If the observable universe encompasses the entire universe, we may be able to determine the structure of the entire universe by observation. However, if the observable universe is smaller than the entire universe, our observations will be limited to only a part of the whole, and we may not be able to determine its... |
why in germany or the netherlands the youth unemployment rate is under 9% while in countries such as greece, spain and portugal the same rate ranges from a 40% to 60%? | It is often a statistical illusion (but not always).
Employment is calculated as "number of people employed" divided by "ACTIVE population" which is the population looking for a job.
In order to have high figure of employment (ie a low for UNemployment), you can either have a high number of people employed AND/OR a LOW active population.
Unlike what most journalists say, an unemployment rate is not the percentage of youth NOT having a job, it is the percentage of youth IN THE ACTIVE POPULATION, not having a job. If almost no youth is in the active population, a high unemployment in that category is not a problem.
Countries have VASTLY different active population, especially for the youth.
If in country A 80% of the youth are full time students not looking for work, and 10% are having a full time job, and 10% are looking for one, you'll have youth unemployment rate of 50% (only 20% are in the labour force, 80% are not so those are not counted to calculate the unemployment).
If in country B you have 50% of the youth as full time students, 40% having a job, and 10% looking for one (ie same overall figure as country A), you'll have a youth unemployment rate of 20%.
But is the country B in a better situation? Are the youth of country B working because they can't afford to study (because studies are too expensive) or because they finished them early (less education than country A) or because they have a better job market?
One needs to ALSO look at the employement/total population ratio. In some countries, it is very high (ie every one works, regardless of age and sex). In others it is very low (only few categories work).
If you look at this data:
_URL_0_
You'll see for the 15-19 age bracket both sexes, VERY different Labour participation rates (ie the number of people actually in the labour force, having or looking for a job):
Germany 28.5% and Greece 8% 2012. So youth unemployement rate of let's say 10% in Germany means 2.85% of total youth are looking for a job. The same 2.85% would mean 35% unemployement in Greece because of its much lower active population.
If you look at the real figures you have for 2012 in
A. Employment/total population:
France (9.7%) Germany (25.8%) Greece (2.8%) USA (26.1%)
B. Labour force/population
France (14.4%) Germany (28.5%) Greece (8%) USA (34.4%)
C. Unemployment rate (A/B)
France (32.7%) Germany (9.2%) Greece (65.7%) USA (24%)
But what does C represents in matter of total population? This is what is important to really gauge the scale of the problem. The number of youth looking for a job/total youth population, ie the UNEMPLOYEMENT/POPULATION. For Greece, this means 65.7% (very high scary figure) but of ONLY 8% of the youth (super low)
Here is the result, ie the percentage of youth unemployed (ie looking for a job) of the total population of youth (and not only those in the active population).
France (4.7%) Germany (2.7%) Greece (5.2%) USA (8.3%)
So the unemployment of youth concerns a much bigger part of the youth population in the US than in Greece... even though its unemployment rate is many times smaller (24% vs 65.7%)...
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"Due to the great recession in Europe, in 2009, only 15 per cent of males and 10 per cent of females between ages 16–19 in were employed full-time. The youth employment rate in the European Union reached an all-time low of 32.9 percent in the first half of 2011. Of the countries in the European Union Germany sticks... |
Why is the way in which colonial powers took over North America viewed today as "stealing", when similar scenarios are often seen as "occupying" or "invading" and then largely forgotten? | Can you give some examples, please? That would help. | [
"Settler colonialism is the act of newcomers/colonizers coming into a place, claiming it as their own and taking great measures to disappear the Indigenous peoples who live their in order to take and exploit the land and resources that yield value. Additionally, settler colonialism is designed to seem inevitable an... |
why is it harder to find veins for injection on someone who's feeling nervous about it ? | So, from a theoretical perspective:
Your body goes through something called sympathetic stimulus during stressful situations - it is colloquially called a "fight or flight" reaction. The body does several things with this, it reduces blood flow to your gut (don't need to be digesting things when running from a tiger), activates insulin (to get glucose into your muscles, where you are gonna need it to run from a tiger), dilated the pupils (so you can see the tiger better), increases blood flow to your heart, and increases heart rate (definitely need that with tigers around), and *decreases* peripheral blood flow (to prioritise the central organs, like your heart and lungs) by constricting your veins. Smaller tubes, less blood in them, more blood for your heart. This increases your blood pressure too.
From a practical perspective, the venous constriction is actually relatively small, certainly compared to other factors affecting how easy it is to get a needle in, like hydration.
Your nervous disposition also has an effect on the person putting the needle in. I am massively needle-phobic, and I really hate cannulating other needle-phobes, cos I know what they are going through, and it makes me feel under massive pressure to get the vein first time, which inevitably makes me miss. | [
"Disadvantages of injections include potential pain or discomfort for the patient and the requirement of trained staff using aseptic techniques for administration. However, in some cases, patients are taught to self-inject, such as SC injection of insulin in patients with insulin-dependent diabetes mellitus. As the... |
how come when i dream something relevant happens in real world? | You dream many things per night and some of them are relevant. Or maybe they are not all that relevant, but can be interpreted in a strange way to make sense to you. Like in your example, it could have been your brother, your father, anyone calling, anyone on the TV etc. you just want it to fit, so it does.
This will be paired with the confirmation bias. You dream 99 nights without it fitting, after that, 1 dream seems to fit "perfectly" like your example and you remember this one but disregard the rest. | [
"Dreaming provides a springboard for those who question whether our own reality may be an illusion. The ability of the mind to be tricked into believing a mentally generated world is the \"real world\" means at least one variety of simulated reality is a common, even nightly event.\n",
"When asked whether the man... |
explain me stocks (what i should look for, what types are there). | Honestly, this is your best shot at learning about [stocks](_URL_2_)
There is no easy answer to any of the things you asked.
Stop spending money as if it grows on trees.
also here are some important links that you might want to take a look at
_URL_0_
_URL_3_
_URL_1_
| [
"Traditionally, stocks are made from wood, generally a durable hardwood such as walnut. A growing option is the laminated wood stock, consisting of many thin layers of wood bonded together at high pressures with epoxy, resulting in a dense, stable composite.\n",
"Stocks are an external framework in a shipyard use... |
how did people used to find their penpal, back in the day? | I found some in the back of a magazine called Stickers, for sticker collectors, back in the 80's. It was in the classified section where people could advertise that they wanted pen pals to write to them about the hobby. | [
"\"Penpal\" is told via a series of non-linear recollections by an anonymous narrator trying to make sense of mysterious events that happened to him during his childhood, the truth of which was kept from him by his mother all his life.\n",
"Penpal is a 2012 self-published horror/thriller novel and the debut novel... |
why do police always show up to places with their sirens on? | If police are doing something sneaky, like a sting, then they won't use a siren.
But the siren gets them through traffic, instructs the public to clear away, and can intimidate criminals (or potential criminals) to dissuade any further crimes. You might think twice about shooting a hostage if you know there are guys outside with guns drawn. | [
"A siren is a loud noise-making device. Civil defense sirens are mounted in fixed locations and used to warn of natural disasters or attacks. Sirens are used on emergency service vehicles such as ambulances, police cars, and fire trucks. There are two general types: pneumatic and electronic.\n",
"Sirens attached ... |
why does "populism" have a negative connotation within democratic societies? | Wiki has this definition:
> Populism is a doctrine that appeals to the interests and conceptions (such as hopes and fears) of the general population, especially when contrasting any new collective consciousness push against the prevailing status quo interests of any predominant political sector.
Basically it's demagogy. Pandering and appealing to emotional knee-jerk parts of people, and tending towards short-term satisfaction, as opposed to logical, rational, long-term and sustainable planning.
| [
"Populism can serve as a democratic corrective by contributing to the mobilization of social groups who feel excluded from political decision making. It can also raise awareness among the socio-political elites of popular concerns in society, even if it makes the former uncomfortable. When some populists have taken... |
why do wifi routers need to be power cycled periodically? are there any that don't? | Routers do NOT need to be reset periodically. If you set it up correctly and installed its firmware then you shouldn’t even be touching it for months or years. If you have an older modem then it could possibly be set on DoD and you’ll need to figure out how to make it a permanent connection. | [
"Each time a router receives a packet, it modifies the packet, decrementing the time to live (TTL). The router discards any packets received with a zero TTL value. This prevents packets from endlessly bouncing around the network in the event of routing errors. Routers are capable of managing hop counts, but other t... |
why do towels have a band without fuzz on each end? | It is there so the towel does not fall apart over time. There are two reasons for using this stitch over the regular "fold-and-stitch" version:
* the fabric is very thick so it would give a very fat fold at the end which does not look appealing
* the frothing does not make it very easy to handle
* as there is no front and back, there is also no side that you could hide this ugly part, eg. in contrast to clothes where usually the seams are on the inside | [
"BULLET::::- A \"beach towel\" is usually a little bit larger than a bath towel. Although it is often used for drying off after being in the water, its chief purpose is to provide a surface on which to lie. They are also worn for privacy while changing clothes in a public area, and for wiping sand from the body or ... |
If we know all the naturally occurring elements and how they combine, is there a finite number of compounds? Do we know them all? Have we synthesized all or most of them?? | It's quite likely we know all naturally occurring elements, as all the ones heavier than those we know are naturally occurring are quite short-lived, and AFAIK it's not believed any more stable elements exist (even if an 'island of stability' may exist higher up, but then they mean _relative_ stability - they'd still be short-lived).
There's a finite, but very large number of compounds. You can build very long polymer chains and very large crystals, although their size is theoretically limited by entropy (although practical limits are far smaller). No matter how strong they're bonded, it's a finite strength, and if you make the chain long enough, it'll statistically be likely to break _somewhere_.
We do not know all possible compounds. Not at all. Although many of the possible ones are just quite boring variations. If you add another amino acid to a protein, you may have a protein that's never been synthesized, but it's not going to differ much in its properties from the original, or other proteins. Not in the way that small compounds are distinct from each other.
However, there are even relatively small compounds we still don't know about, because it's not always easy to predict whether a molecule is stable or not (especially if it doesn't much resembles ones we know already), nor predict how stable it is if it exists. We're also discovering new states and properties of old and well-known elements, e.g. it was fairly recently discovered that stable compounds of Fe(VI) were existed, where it'd previously only been thought to exist as an intermediate in certain reactions, at most.
There are a number of 'theoreticals', compounds that are predicted to be stable, but which we don't know how to synthesize, often because they're high-energy compounds. One example is Td-N4, four nitrogen atoms should be able to form a (somewhat) stable tetrahedron, with each bonded to three others. Nobody has been able to produce it yet though.
| [
"All elements with atomic numbers 1 through 94 occur naturally at least in trace quantities, but the following elements are often produced through synthesis. Technetium, promethium, astatine, neptunium, and plutonium were discovered through synthesis before being found in nature.\n",
"The elements from atomic num... |
Why do positron-electron pair not annihilate each other? | To answer the question in the title: electrons and positrons do annihilate eachother.
To address the [different] question in the body of the post: the matter–antimatter asymmetry of the universe is an unsolved problem. Perhaps there are processes that violate lepton number or baryon number (key ingredients in generating the asymmetry), but we haven't observed anything like that yet. | [
"The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. When a low-energy positron collides with a low-energy electron, annihilation occurs, resulting in their conversion into the energy of two or more gamma ray photons (see electron–positron annihilation).\n",
"The positr... |
what are pilots checking during pre/post flight? | Not everything on the checklist will ground the plane, but some things can. For example, during flight a bird might have damaged a [pitot tube](_URL_0_). That wouldn't ground a plane by itself (unless *all* of them were damaged by a flock of birds), but you'd need to clean them out at the very least, and certify they were working properly before you could fly.
Other items on the checklist make sure that the plane is ready for flight. Is it snowing/cold outside? Turn on engine anti-ice. Are your outboard lights on (so other planes can see you)? Are your radios setup on the correct frequencies? Did you program the flight computer? etc.
As for post flight, that's mostly to do with shutting down the electrical systems and engines in a safe manner. When you're on the ground, you're generally connected to ground-based power. You still need to switch the plane over to actually use this power, and ensure that things like the APU are not generating power. You also don't want to drain your batteries. Also, no sense in trying to pressurize the cabin when the door is open. The checklists exist to make sure you turn all the knobs and dials you're supposed to turn because despite the automation, there is still a LOT of settings that can/should be tweaked on a plane. | [
"In aviation, a preflight checklist is a list of tasks that should be performed by pilots and aircrew prior to takeoff. Its purpose is to improve flight safety by ensuring that no important tasks are forgotten. Failure to correctly conduct a preflight check using a checklist is a major contributing factor to aircra... |
why does yawning temporarily make a headache go away? | Headaches are mostly caused by misfiring nerves in your brain (migraines) or "heartbeat"/pressure headaches in the nerves/vessels/muscle that surround your brain.
Yawning causes a few things to happen in your body: it increases oxygen in your blood stream, increases blood flow around your jaw as you use the muscles (which is why you sometimes hear a "whooshing" as you stretch/yawn) and relieves pressure imbalances in your sinuses (when your ears pop). All three of these effects can impact headache pain.
The most significant "immediate" effects on your headache are pressure balancing and muscle stretching - especially for non-migraine headaches. Pressure in your sinuses can cause the sinus walls to trigger nearby nerves, making them to react in a throbbing pain that is relieved by a temporary release of pressure while yawning. The pain will, of course, come back when the pressure is unbalanced again
If your headache is caused by dehydration or a hangover, your brain has slightly shrunk and pulled away from your skull, alerting the nerves in a painful way (esp at your temples). By yawning, you are stretching the muscles in your jaw and temples, making nearby nerves fire a sense of "pleasure" that overrides the "pain" from dehydration - it's a very similar principal to rubbing an area near an injury to reduce the feeling of pain. Once you are no longer doing that, the pain returns. Yawning also stretches muscles that can be tight with painful tension (due to stress or exhaustion), and the temporary relax + stretch makes nerve firings associated with constricting your muscles go away.
Yawning during migraines is a little different because migraines are (to our current understanding) misfires of nerves within the brain itself. Yawing is usually a sign that a migraine is coming on, likely because the brain is reacting to random nerve firings the same way it reacts to exhaustion - by trying to get more oxygen. There is no real evidence that yawning lessens migraine pain in a physical way caused by an increase in oxygen, but the action may temporarily district you from your headache. | [
"Still another hypothesis suggests yawns are caused by the same chemicals (neurotransmitters) in the brain that affect emotions, mood, appetite, and other phenomena. These chemicals include serotonin, dopamine, glutamic acid, and nitric oxide. As more (or fewer) of these compounds are activated in the brain, the fr... |
Is there a name for the feeling you get when you see something that makes you cringe? | [Might not be what you're looking for exactly, but this site has a plethora of definitions that haven't been captured by words by an official dictionary yet. You might find a word that means that here](_URL_0_) | [
"Observing video clips that displayed facial expression of feeling disgust activated the neural networks typical of direct experience of disgust. Similar results have been found in the case of touch. Watching movies that someone touched legs or faces activated the somatosensory cortex for direct feeling of the touc... |
How did Gen James Longstreet go from Lee's right-hand man to pro-Reconstruction Republican? | In a word, Longstreet was a realist. He accepted that the South has lost, and was looking for the best way for her to bounce back. But while he wasn't alone in the former officer corps in his caution "to accept the terms that are now offered by the conquerors" following the implementation of Reconstruction in 1867, he was fairly unique in his advocacy for actual cooperation, which resulted in considerable vilification by Southern veterans and writers over the next few decades. Maybe if he had kept is views to himself it wouldn't have been so bad, but he put them in a letter that was published in a New Orleans newspaper. [I don't know if the entire text is available, but "Lee's Tarnish Lieutenant" has a fairly extensive quotation](_URL_0_). In short though, He was arguing that cooperation with Republicans was essential in order to best be able to mitigate the adverse effects of Reconstruction - "if whites won't do it, the thing will be done by the blacks" - and additionally that ensuring a Southern presence within the Republican party was essential to limiting the ability of the newly enfranchised African-Americans to have any real power with their vote.
As you can see, his views are still fairly offensive as far as our ideas of racial equality goes, but for a Southern audience, still smarting from defeat, and still *pretty* damn racist, he might as well have just waved a white flag. Most of them weren't willing to give even an inch, and of course, as the next few decades would bear out, the South was fairly effective in ensuring the failure of Reconstruction, and the continued subjugation of the African-American population under Jim Crow. It didn't matter to them that Longstreet firmly believed he was advocating in Southern interests, and for the continued marginalization of the Black population at that. The Republican Party was *the enemy*. It was everything that stood in opposition to white, Southern civilization. One of the most core aspects of the Southern views on their defeat was to ensure that their honor remained intact - defeated on the battlefield but not in spirit. Longstreet's path went against that, however much his long term view of the continuance of a white dominated South may still have aligned.
Longstreet perhaps could have defended himself, but he simply never really tried, at least in the early days. A few private letters exist which speak to his commitment to white supremacy, but he never made strong, public statements to that effect in order to clarify his position. It didn't help that within a few months, he was granted his Federal pardon, which would allow him to again run for office, and of course led to accusations of abandoning the Confederate cause out of sheer self-interest.
He then just keep digging that hole deeper, endorsing Grant for the presidency, and then accepting a Federal job in the Port of New Orleans. This just only continued to feed Southern attacks on his generalship and character, and soon enough, Longstreet was essentially the sole cause of Southern defeat, having been made the lynchpin of defeat at Gettysburg, and in turn Gettysburg the lynchpin of defeat in the war itself. It was essentially a vicious cycle, with each side acting and reacting to further entrench the other's position. When, in 1896, he published his memoir and dared speak an ill-word of General Lee in defense of himself, well, he might as well have taken a dump on Jesus Christ himself as far as Southern audiences were concerned. While he wasn't exactly at Sherman's level, Longstreet had very much come to be a villain of the 'Lost Cause' narrative as it was formed in the late 19th century.
James Longstreet and the Lost Cause by Jeffry D. Wert, in The Myth of the Lost Cause and Civil War History, edited by Gary W. Gallagher & Alan T. Nolan
Lee's Tarnished Lieutenant by William G. Piston | [
"Longstreet was one of a small group of former Confederate generals, including James L. Alcorn and William Mahone, to join or ally with the nationally dominant Republican Party during the Reconstruction era. He endorsed Grant for president in the election of 1868, attended his inauguration ceremonies in Washington,... |
hasidic judaism (or jewish mysticism) | Alright, first of all, not all Chasidim (-im generally means plural people in Hebrew) are mystics, nor are all mystics Chasidim. But you will usually find more Chasidic Kabbalah scholars than you will Reform. (Anecdotal evidence: I knew a Chabadnik who started Reform and eventually became Chabad.)
Chasidim (and especially the Chabadim, one of the most popular form of Chasidic Judaism in the US) feel that besides devotion to G-D, one must study G-D's ways as well. The Chabad movement took it further and said that it wasn't enough to just give G-D and Judaism your heart; you had to give your mind and your wisdom as well. No mindless devotion to the Law for them! They believe in studying always the Talmud (thousands of years of commentary on the Torah, the first five books of the Bible) and don't think that just saying the prayers and keeping the commandments are good enough. One has to always be learning.
Rabbis in the Chabad (and also most Chasidic movements) are not priests or superiors, so much as they are a supervisor of sorts. (One thing that drew me back to my family's Judaism was the idea that one is expected to argue with the rabbi, as that is one of the best ways to learn. True, he'll usually win, but that's not the point.)
So -- Chasidic Jews are Orthodox Jews who devote themselves to a strict interpretation of the Law. Chabad also devote themselves to learning, to spreading wisdom, and to a general appreciation of life. If you're ever at a Jewish meal, and there's one guy with long hair, a long beard, and a glass of vodka in his hand, telling you that G-D commands all to make three *l'chayim* (toasts) in his honor, that's the Chabadnik.
(By the way, the 'ch' can be spelled or pronounced as 'H' and you won't be too wrong. But properly... pretend you have a hair in the back of your throat, and you're at dinner with your girlfriend's family, so you don't want to just cough it out in front of them. That gentle throat-clearing... THAT'S the Hebrew 'ch.')
EDIT to finish your question: A general view of the other branches of Judaism:
Orthodox: for all practical purposes, follows all the *mitzvot* or commandments. They keep all the dietary laws, they pray in separate rooms in the Synagogue (Men in one, Women in the other... it's supposed to keep your mind off the other sex), and do their best to live the way the Torah and the Talmud say Jews should live. Chasidic Jews are almost always Orthodox. The way they live and worship is generally the same since the Second Temple was destroyed in AD 70. (Of course, they use technology... except on the Sabbath. From sundown Friday to sundown Saturday, they will not drive, turn on (or off) any appliance, and do no work whatsoever. Most congregations have a "Shabbos Goy," a non-Jew who will turn things off, lock up the Synagogue, and other little tasks that have to be done.)
Reform: this movement does their best to blend in with the surrounding population. They may or may not keep all the dietary or cultural laws, but they still say the prayers and practice Judaism. For a long time, they were the only ones who had female rabbis, but this is slowly starting to change.
Conservative: this movement sprang up as an answer to Reform Judaism, and is roughly a happy medium between the two. Many conservative will make small changes to the cultural laws in order to better live in society. There are Conservative female rabbis, now, and women in the congregation are more engaged. You won't see one firing up the barbecue to cook up some pork ribs on Saturday morning, but they may be a little more lax on the laws (on a personal basis) than Orthodox.
EDIT #2: Meant to say that Chabad is *one of the* most popular forms of Chasidism in the US. | [
"Thus, although there is an esoteric tradition in Judaism (Kabbalah), Rabbinic scholar Max Kadushin has characterized normative Judaism as \"normal mysticism\", because it involves everyday personal experiences of God through ways or modes that are common to all Jews. This is played out through the observance of th... |
How do sun rays affect clouds and their changes? | Well, sun is the energy source in the formation of clouds. Actually, sun is the main energy source of all atmospheric movements. But I assume that wasn't your question (if it was, let me know.)
Once the clouds are formed, sun rays don't affect them **directly** because clouds are poor absorbers of short-wave radiation (which is the lenghtwave in which the sun emits). Most of the incoming solar radiation gets reflected back to the top of the atmosphere by clouds, and they also scatter the visible light in a way that makes clouds appear white, but they don't get heated or evaporated by direct solar radiation.
Hope it helps. Sorry for bad english :P
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"In addition to their direct effect by scattering and absorbing solar radiation, aerosols have indirect effects on the Earth's radiation budget. Sulfate aerosols act as cloud condensation nuclei and thus lead to clouds that have more and smaller cloud droplets. These clouds reflect solar radiation more efficiently ... |
Do wolves panic during thunderstorms the way domesticated dogs sometimes do? | Dogs panicking during thunderstorms only primarily happens because they aren’t conditioned to the sound before formative development in the brain stops. Dog trainers can suggest playing different sounds—cars honking, trains, thunderstorms, alarms, etc.—while puppies are young so they get used to the sounds and don’t panic when they hear an unfamiliar sound. Since wolves are in the elements 100% of the time, I assume pups hear the sound of a thunderstorm before that brain development cuts off, and are normalized to it.
Not a zoologist or wolf expert—just have a puppy that I’ve done tons of research on so that he doesn’t panic during thunderstorms. | [
"Wolves kill dogs on occasion, with some wolf populations relying on dogs as an important food source. In Croatia, wolves kill more dogs than sheep, and wolves in Russia appear to limit stray dog populations. Wolves may display unusually bold behavior when attacking dogs accompanied by people, sometimes ignoring ne... |
why is the ph of water important for plants but not animals? | My tomato plants that I'm growing hydroponically (i.e. in water) grow within a pH range of about 5.5-7.0
My fish grow in a range of about 6.5 - 7.0.
So I think pH of water is important for both plants and animals, and probably even more important for animals? But it probably depends a lot on which plants and which animals, are they're all likely to have different abilities to cope with different pH levels.
Which animals and plants were you talking about in your question? | [
"Soil pH is considered a master variable in soils as it affects many chemical processes. It specifically affects plant nutrient availability by controlling the chemical forms of the different nutrients and influencing the chemical reactions they undergo. The optimum pH range for most plants is between 5.5 and 7.5; ... |
why do tomato based foods stain tupperware? | Tomatoes contain a compound called lycopene that reflects light strongly in the red portion of the visible spectrum. The lycopene binds to the plastic in the container causing it to take on a reddish tint. | [
"Lycopene is the pigment in tomato-containing sauces, turning plastic cookware orange, and is insoluble in water. It can be dissolved only in organic solvents and oils. Because of its nonpolarity, lycopene in food preparations will stain any sufficiently porous material, including most plastics. To remove this stai... |
dust | Dust is made of a collection of things: dead skin, dust mites, dust mite feces, pollen, smoke, soil, hair, and other materials. Dust particles are very small and light so they get blown around easily in the air. They spread out to fill a room top-to-bottom like a [cloud in a bottle](_URL_0_) but for your whole house.
Some of the dust settles onto surfaces. Some surfaces, like doorknobs, you constantly touch which wipes the dust off the surface, before it builds up to a point where you can see it. If it's a surface that rarely gets disturbed, like the top of your television, it keeps building up until you grab a washcloth and wipe it down. | [
"Dust is made of fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil, dust lifted by wind (an aeolian process), volcanic eruptions, and pollution. Dust in homes, offices, and other human environments contains small amounts of pla... |
Before the arrival of the Magyars, who lived in Hungary? | The Iazyges were a nomadic Sarmatian tribe located in around where Romania, Ukraine, and Hungary meet today. They were a constant thorn in the side of the Roman Empire from the 1st Century BCE. They constantly resisted assimiliation and were among the last of the Dacian peoples to be quelled. In the late 1st Century CE, they crossed the Danube into Roman Pannonia and defeated Legio XXI Rapax (who were disbanded afterwards). It was only when Trajan took control of the Empire (and the war in Dacia) where the Iazyges were conquered. In fact, future emperor Hadrian was the one that forced them to submit. They were reduced to a client state of the Roman Empire after this (107 CE).
EDIT: Professor pronounced them (ee-uh-zee-gees)
| [
"Hungarians have had a thousand year old, and still living tradition about the Asian origins of Magyars. This tradition was preserved in medieval chronicles (such as Gesta Hungarorum and Gesta Hunnorum et Hungarorum) as early as the 13th century. This tradition served as starting point for the scientific research o... |
Does the total volume of precipitation in the sky vary? If so, by how much? | Unsure what you are asking. Are you asking if the amount of water vapor varies? If so, it clearly does because humidity varies widely over the Earth. | [
"Precipitation is distributed fairly evenly over all months of the year, and mostly originates from a westerly airflow. There is significant variation in precipitation with altitude. For example, Chamonix has an elevation of approximately and receives around of annual precipitation, whilst the Col du Midi, which is... |
Before photo ID's how did people prove their identity? How would you get a check cashed? | More of a legal history perspective, but contracts historically were based on trust. Basically you could cash a check because you said you were the person on the account. You would only need to prove your identity if there was something wrong with the transaction (someone else claimed it, the check was returned, etc.).
If in court you needed to prove your identity, you would have to do so by a preponderance of the evidence, which is to say that you would prove that it is more likely than not that you are who you say you are. You would use whatever you had at this point, family bible, a deed, a birth certificate if you had one, etc. | [
"For financial transactions, ID cards and passports are almost always accepted as proof of identity. Due to possible forgery, driver's licenses are sometimes refused. For transactions by cheque involving a larger sum, two different ID documents are frequently requested by merchants.\n",
"Photographic identificati... |
Why is Australia so hot even though it is so far south of the equator? | Australia isn't that far south - depending on whether you're talking Darwin or Tasmania, you're roughly looking at the same latitudes as northern hemisphere locales such as Syria, Iraq, Spain and Mexico - all fairly warm in their own right.
Australia's also affected by a strong warm-water current, the Eastern Australia Current (or "E.A.C. of *Finding Nemo* fame). This is like the analog of the northern Atlantic's Gulf Stream, shunting warm equatorial Pacific water directly down Oz's eastern shore. So just as the Gulf Stream keeps the British Isles several degrees warmer than they would otherwise be (there are even a few palms in southern Ireland), the E.A.C. warms up that part of Australia that most Aussies call home.
Finally, it's notably, remarkably, lacking in mid-continent bodies of water that might ameliorate inland temperatures. | [
"Australia's tropical/subtropical location and cold waters off the western coast make most of western Australia a hot desert with aridity, a marked feature of the greater part of the continent. These cold waters produce little moisture needed on the mainland. A 2005 study by Australian and American researchers inve... |
why is murder always the most severely punishable crime? | Imagine a society where there are only two capital crimes: murder and robbery. For the sake of argument let us say any crime with a surviving victim has a 75% chance of being "solved" and any crime with a dead victim has a 45% chance of being "solved."
If you murder someone, there is a 45% chance you will be caught, tried, and then executed.
If you rob someone and then leave them alive, there is a 75% chance you will be caught, tried, and then executed.
If you rob someone and then murder them, there is a 45% chance you will be caught, tried and then executed.
See how murder just changed you chances of execution from 75% to 45%? That is exactly what a lawful society should avoid. You never want to make murder attractive for a criminal. You want, if possible, to maximize the chance the victim lives and the criminal is brought to justice.
Your punishments should be tiered to reflect this. You want the criminal to think "Killing this person isn't worth the smaller risk of much greater punishment." | [
"Most societies consider murder to be an extremely serious crime, and thus believe that the person charged should receive harsh punishments for the purposes of retribution, deterrence, rehabilitation, or incapacitation. In most countries, a person convicted of murder generally faces a long-term prison sentence, pos... |
airplane formations | Different formations serve different purposes. Some just look good for display, and some are designed to maximize the aircraft's effectiveness in combat.
Especially in the pre-missile-and-radar days it was important for combat aircraft to fly in mutually supporting formations. Bombers flew in tight box formations to maximize the effect of their defensive guns. Fighters generally flew in 2-ship elements. You attack, your wingman watches your back. Other elements of the formation would stay high, to watch for enemy fighters, etc. | [
"Several variants of the formation are seen. The formation most commonly used in the United States is based on the “finger-four” aircraft combat formation composed of two pairs of aircraft. The aircraft fly in a V-shape with the flight leader at the point and his wingman on his left. The second element leader and h... |
Are there any well written/ researched historical books specifically about the America atomic dread and how it influenced culture and art? | Indeed, there are!
My favorite, for its breath and scope, is Spencer Weart's _Nuclear Fear: A History of Images_ (1988). There is a revised/updated edition out recently as well, though I prefer the original. It covers public attitudes (in a number of countries) about radioactivity and nuclear energy from the 19th century through the 1980s. It is very well written and one of my favorite academic books.
The other big book on this, though its time period and geographical focus is much narrower, is Paul Boyer, _By the Bomb's Early Light: American Thought and Culture at the Dawn of the Atomic Age_ (1985/1994).
There are other books on this subject as well, though I think most historians would list these at the very top. | [
"\"The Atomic Cafe\" was released at the height of nostalgia and cynicism in America. By 1982, Americans lost much of their faith in their government following the Vietnam War, the Watergate scandal, and the seemingly never-ending arms race with the Soviet Union. \"The Atomic Cafe\" reflects and reinforces this ide... |
How did Jefferson Davis get out of treason charges? | The short answer is there are a variety of reasons. This actually goes into law a little bit so I will be in uncharted territory.
So Davis was indicted for treason. But when he went before the judge his team argued that due to the 14th Amendment he was already punished for insurrection against the US, as under the 14th Amendment anyone who takes an oath of public office and commits an insurrection can no longer hold public office.
However the chief justice gave him an interesting argument. As Davis was president of another nation, he wasn't technically a citizen and couldn't be tried for treason for that reason.
In the end, Andrew Johnson pardoned him and all ex-confederates anyways, so any outcome would have been moot due to this. | [
"Davis was indicted for treason but never tried; he was released from prison on bail in May 1867. The amnesty of December 25, 1868, by President Johnson eliminated any possibility of Jefferson Davis (or anyone else associated with the Confederacy) standing trial for treason.\n",
"Jefferson Davis was imprisoned at... |
why does light only penetrate 1000 meters of the ocean and not the entire ocean? | No one seems to be answering your question with photons:
Think about light from the sun as a hail of lots of photons.
Each photon travels until it hits something. Some things can “bounce” photons off them, some things just suck in the photon.
Lots of photons from the sun make it through the air and start travelling into the water. But seawater has stuff floating in it that absorbs photons. For each metre of water, some photons will hit something, and some will make it through without hitting anything.
If you look for photons 300 metres deep in the sea, you will only find the very lucky photons who made it through 300 metres of water without hitting anything, and hardly any photons are that lucky.
Edit: I just thought of a good analogy – it’s like a crazy guy spraying a machine gun around in a forest. Bullets stop when they hit a tree, but some bullets can go quite far before they hit a tree. If you can get a mile away from the crazy machine gun guy, your chances of getting hit go down to practically zero.
Edit 2: please stop accusing me of being an American. | [
"The amount of light that penetrates the sea depends on the angle of the sun, the weather conditions and the turbidity of the water. Much light gets reflected at the surface, and red light gets absorbed in the top few metres. Yellow and green light reach greater depths, and blue and violet light may penetrate as de... |
If you have an addiction, and suddenly get amnesia, will you know what you crave, even if you can't remember it consciously? | Amnesia, to my knowledge, only affects conscious memory, so you will still have the cravings but you most likely will not remember what you are craving. | [
"Drug-induced amnesia is the idea of selectively losing or inhibiting the creation of memories using drugs. Amnesia can be used as a treatment for patients who have experienced psychological trauma or for medical procedures where full anesthesia is not an option. Drug-induced amnesia is also a side-effect of other ... |
doing x in your life decreases/increases your risk of getting y cancer by z%. how do they determine the percent risk? | They look at a sample of the population, made up of varying groups within that sample, and they look at their habits and the outcomes.
If they notice that some men are not getting cancer while others are, or some men are being hospitalized for similar reasons while others aren't, they then look at the similarities between the men are try to find a cause.
Once they have that cause, they try and look at why it might be the case.
For cigarettes they know that people who smoke and inhaling cancerous chemicals, and that's why their risk of cancer is increased.
For (I'm assuming coffee) drinkers, it might be because the caffeine is A) giving their heart a boost and a little work out by beating faster and therefore minorly improving cardio B) caffeine is a diuretic and therefore may flush stuff out of the body
They then run more tests to conclusively prove these theories and then release the information. | [
"For example, when studying risk factors of cancer, the cancer process may have been triggered long before actual diagnosis of cancer, and that therefore any exposure to risk factors in the \"lag\" time between may be unimportant.\n",
"The ICPR 65 model follows the same approach, and estimates the relative lifelo... |
baby boomers and the animosity towards them | Copy-Pasta of my comment from [this thread](_URL_0_).
> When the US had crushing debt after WWII, the top marginal tax rate was raised to over 90%(!!!). Our debt was far worse than today and the WWII generation was not willing to pass that debt on to their children. This WWII debt was paid off relatively quickly and responsibly.
>
> The boomer generation is very often criticized because they have been hesitant to take similar action in the public sphere. The Cold War again caused national debt to skyrocket, but instead of raising taxes, they lowered them and let the debt balloon. Instead of reforming programs that are on shaky ground, they insist the government not touch them.
>
> To many, they just seem awfully close to violating the Boy Scout Rule, not leaving the country better than they found it. The 60s-70s were no utopia, don't get me wrong, but people see problems they definitely could have solved or at least contained which they did not.
Their stewardship of the country has left a lot to be desired in many peoples' eyes. | [
"Baby Boomers, born approximately between 1946 and 1964 were brought up in a healthy post war economy and saw the world revolving around them as the largest generation of the century. Their lifestyle is to live for work and they often expect the same level of dedication and work ethics from the next generations. Th... |
Do bent space-time and gravitons both cause objects in space to attract one another? | They are different descriptions of the same thing. Changes in the gravitational field propagate as gravitational radiation, and quanta of gravitational radiation are called gravitons. The classical limit of a spin-2 massless (graviton) quantum field theory is general relativity. | [
"This is because gravitation is an attractive force, but if there is an underdense region it apparently acts as a gravitational repeller, based on the concept that there may be less attraction in the direction of the underdensity, and the greater attraction due to the higher density in other directions acts to pull... |
what is the purpose of the black paint under the eyes? | It reduces glare (reflection off your upper cheekbones) from the sun/lights and makes it so that you do not have to squint as much. Besides being used in many sports, it is also used by hunters and military/ warring peoples. As for historical context, it's been done for a very long time because it's copied from nature - many non-human animals like cheetahs and gazelles naturally have the useful glare-reducing darkness under their eyes. | [
"The two main forms of eye makeup were grepond eye paint and black kohl. The green eye paint was made of malachite, a copper carbonate pigment, and the black kohl was made from galena, a dark grey ore. Crushed charcoal was also used in this process. Mesdemet or Kohl was used for lining the eyes and were revealed to... |
Why can an inner ear infection cause temporary taste loss? | Oh so this is SUPER cool. Sorry, probably not for you, but I'm a huge dork.
There's a nerve called the chorda tympani which passes through the middle ear, and I'm making an assumption here that you actually had a middle ear infection, as they are far more common. It is one of three nerves that carry taste sensation from the tongue to the brain, and my bet is that irritation of this nerve leads to temporary taste loss.
Source: ~~Medical student. But I haven't brushed up on my anatomy in a while. This is, of course, not medical advice.~~ Good 'ol [Netter's Anatomy Atlas](_URL_0_) | [
"Lesions to the olfactory nerve can occur because of \"blunt trauma\", such as coup-contrecoup damage, meningitis, and tumors of the frontal lobe of the brain. These injuries often lead to a reduced ability to taste and smell. Lesions of the olfactory nerve do not lead to a reduced ability to sense pain from the na... |
Is an insect that lives for 1 hour much faster evolving than humans who reproduce every 657 000 hours? (30 years) | My brain is foggy, but there were many studies that get done on fruit flies for mutations because of their quick life span and how many offspring each can create.
EDIT: Here is an example that goes into more details than I could ever remember: _URL_0_
To quote the article for the lazy:
"Since the early 1900s, multiplied millions of fruit fly generations have been bred in laboratories across the globe. Scientists performing these experiments have introduced fruit flies to various levels of radiation and countless other factors designed to produce mutations. Sherwin noted that over 3,000 different mutations have been documented in the fruit fly gene pool (n.d.). These mutations have caused such physical characteristics as eyeless flies, flies with different colored eyes, flies with legs growing from their heads, extra pairs of wings, various colored bodies, wingless flies, flies with unusually large wings, flies with useless wings, flies with twisted wings, etc. The list could go on for hundreds of pages." | [
"The mite has been recorded at a speed of 322 body lengths per second (). This is far in excess of the previous record holder, the Australian tiger beetle \"Cicindela eburneola\", the fastest insect in the world relative to body size, which has been recorded at or 171 body lengths per second. The cheetah, the faste... |
how are people able to salvage data that has been deleted? | Data isn't actually deleted when you hit "delete". When you hit "delete", you're telling the Operating System that it is OK to overwrite the area the data is taking up. If you delete something by mistake, and you don't write anything to the disk, the data is still there, and you can recover the data. | [
"Recovery experts do not always need to have physical access to the damaged hardware. When the lost data can be recovered by software techniques, they can often perform the recovery using remote access software over the Internet, LAN or other connection to the physical location of the damaged media. The process is ... |
After WW2, Hirohito was allowed to remain as a symbolic head, Why? | /u/restricteddata previously answered [Why was Emperor Hirohito allowed to keep the throne after Japan's unconditional surrender in WWII?](_URL_1_)
/u/vinco_et_praevaleo previously answered [How did Emperor Hirohito escape trial and death following the Second World War?](_URL_0_)
EDIT: fixed typo | [
"After Japan's defeat in World War II, there were suggestions to legislate the \"hinomaru\" and \"Kimigayo\" as the official symbols of Japan. However, a law to establish the \"hinomaru\" and \"Kimigayo\" as official in 1974 failed in the Diet, due to the opposition of the Japan Teachers Union that insists they hav... |
why do some batteries puff up? | A swollen battery is the result of progressive degradation of the chemicals that generate power. The reaction that pushes electrons through the circuit can't work the way they were designed to, and part of that failure involves *outgassing,* or the creation of gases and vapors where they're not intended. This swells the battery casing, and might cause a breach and leak of the battery's contents. | [
"If the battery is over-filled with water and electrolyte, thermal expansion can force some of the liquid out of the battery vents onto the top of the battery. This solution can then react with the lead and other metals in the battery connector and cause corrosion.\n",
"Voltage depression is caused by repeated ov... |
Is there a certain configuration for a wifi router's antennas to give better reception? | You want to set up antennas perpendicular to the direction of motion of the signal. So, if you're in the room next door, you would want the antenna to be vertical. If your router was in the basement and you wanted signal directly above it on the roof, you would want the antenna to be perfectly horizontal. | [
"Fixed wireless services typically use a directional radio antenna on each end of the signal (e.g., on each building). These antennas are generally larger than those seen in Wi-Fi setups and are designed for outdoor use. Several types of radio antennas are available that accommodate various weather conditions, sign... |
How does sound pass though objects, but light (mostly) cant? | Sound waves are a series of uncompressed and compressed molecules. When you slam your book on your table, the molecules of the book pushes the table surface molecules down, which gets them pretty close to the next set of molecules. The first group then retracts since they don't want to be so close to the other molecules, and the same goes for the second set of molecules, except they push further down. This continues until the energy dies out, or when it reaches the other side of the table, except the molecules being pushed are air molecules, which will also continue until the energy is lost. This *is* a sound wave, so it's not the fact that sound waves are traveling through an object, it's that the sound wave is manifested *in* the object(s).
| [
"However, if the object has a diameter greater than the acoustic wavelength, a 'sound shadow' is cast behind the object where the sound is inaudible. (Note: some sound may be propagated through the object depending on material).\n",
"The mechanical vibrations that can be interpreted as sound can travel through al... |
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