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Would a child from 10,000 years ago fit in if raised from birth in today's society, 100,000 years? How far back could we go before we have a significant degradation of cognitive ability? | I think probably from about 200,000 - 100,000 years ago cognitvely, as this lines up with migrations out of Africa. However in terms of a decent immune system you are probably looking at about 10,000 - 7,000 years ago as this lines us with the first instances of livestock rearing by humans and therefore the development of some immunity to alot of modern day pathogens. | [
"The population of children under age 5 grew by 6% (293,000) over the ten-year period between 2001 and 2011. However, the number of children aged 5–14 fell by 11% (69,000). The population of people over 65 also grew by 11% (85,000) and they now represent 17% of the total population and for the first time there are ... |
why can't we just plant the gros michel banana again? | Why would we want to?
It's the Cavendish that's a) far more popular and b) threatened by a fungus infection (though not as critically as some hysterical sources claim).
The reason we can't just plant more of ANY type is because modern cultivated bananas are seedless, sterile mutants. The way you get a new banana plant is by cultivating a cutting, which makes them all clones, and thus, susceptible to the same diseases.
| [
"Contrary to common belief, growing banana trees is not that difficult and allow people to enjoy their own bananas. Also these plants can be used as windbreaks. They need fertile soils, large mulch and organic matter, large amounts of nitrogen and potassium, warm temperature, high humidity, large amounts of water, ... |
Aztec religion - Was there an actual name for it? What were their beliefs/rites/festivals about? Were some gods worshiped more than others? | This is a very broad question, but a good start to learn more is "The Lost History of the Aztec and Maya" by Charles Phillips. He uses ancient primary sources to summerize MesoAmerican legends and myths. He also lists the eighteen major Aztec festivals and describes the rituals of these religious holidays.
The Aztecs were polytheistic, but some gods were more important than others. The largest pyramid in the center of Tenochitlan had two temples. Huitzilopochtli, their humming-bird war diety was perhaps the only purely Aztec god. They worshiped him while they were still nomads living in the arid country north of the Basin of Mexico. After the Aztecs took over the Basin, they allowed older more established gods to continue. Tlaloc was a much older rain god. Tlaloc was the most important diety at Teotihucan, and this religion was more than a thousand years old, when the Aztecs included a temple to Tlaloc on top of their biggest pyramid. Other important Aztec dieties include Tezcatlipoca and Quetzalcoatl, who were the good guy/bad guy in an earlier Toltec myth, that survived in an Aztec codex. The Aztecs seemed to have favored the bad one, Tezcatlipoca. His temple is bigger than the Quetzalcoatl temple, and there are more survivng myths about him in the Aztec sources.
| [
"The many gods of the Aztecs can be grouped into complexes related to different themes. The Aztecs would often adopt gods from different cultures and allow them to be worshiped as part of their pantheon – the fertility god, Xipe Totec, for example, was originally a god of the Yopi (the Nahuatl name of the Tlapanec ... |
what is the difference between an architect and an architectural enginner? | An architect says “Wouldn’t it be cool if my building looked like *THIS*?”
And the engineer says, “Yeah, here’s how to make it not fall over.” | [
"The architect is usually the lead designer on buildings, with a structural engineer employed as a sub-consultant. The degree to which each discipline actually leads the design depends heavily on the type of structure. Many structures are structurally simple and led by architecture, such as multi-storey office buil... |
why do men joke about their penises so much? | Because it's hard not to.
Heyo
Penis jokes are just very basic humour, low hanging fruit. It's universal, everybody past puberty gets it. But they're not classy, so don't whip them out whenever.
You can tell a penis joke once in a while, just don't be a dick about it. | [
"Some men use the waistband in order to hide a genital bulge (also known by the slang terms \"man-bulge\" or \"moose-knuckle\") in order to avoid embarrassment. During an erection, this is done by jutting it upwards beneath the waistband. This approach may on occasion be colloquially and informally referred to by s... |
If all but one species of dog died out, could we theoretically recreate all of those lost species by selective breeding? | This is probably just a matter of semantics, but I would like to point out that when you say "if all but one species of dog died out...", you're really talking about breeds of dog, not species. All dogs are the same species. | [
"Because of the treacherous conditions in which this breed of dog was used, coupled with a succession of accidents, talk of the whole stock becoming extinct was raised as early as 1839. However at some point prior to 1847 a pestilence swept through the region and reduced the number down to a single specimen, which ... |
why do parliament impose sentence ranges for crimes instead of leaving it up to the judge and case law? | It's important to have some degree of uniformity in sentencing. Of course every case and every criminal is different, but some guidelines are necessary.
In County A you get arrested for possessing heroine and the judge happens to think drug laws are a bit silly and gives you 10 days in jail. Get arrested for the same crime in County B and the judge not only really hates drugs, but lost his son to a heroin overdose, and he sentences you to 10 years.
Your punishment should be based on how bad your crime was, not which judge you got. Sentencing guidelines help to bring some uniformity and reduce the role of the judge. | [
"The type and maximum level of sentence for each offence is fixed by Parliament in statutes known as Acts of Parliament. For example, the crime of the theft has a fixed maximum of seven years imprisonment. Some offences have a maximum of life imprisonment: these include manslaughter and rape. In such cases the judg... |
why is it easy to hear someone talking outside when you’re in a car but hard to hear someone inside talking when you’re outside the car? | I’d assume when you’re outside you’re battling more things to be heard (wind/weather/cars) so you naturally talk louder at a point you can be heard from within a nearby vehicle
When you’re inside a car your windows and such block out most of this noise pollution or atleast reduce it so you’re not shouting to each other | [
"There is also a phenomenon known that while crossing a street, an individual can hear the sound of an oncoming car. However, when they look to the left the next car is a few blocks away so it is safe to cross. But when they look to the right, there is a car that is passing them that they did not even notice before... |
why do our testicles hang lower when warm and move closer to the penis when cold? | Balls are meant to stay at temperatures cooler than the rest of the body. Sperm production gets negatively impacted at higher temperatures.
So, when body is hot, then to maintain a lower temperature, balls hang in the sack.
When body is cold, balls don't need to distance themselves from the rest of the body. | [
"As sexual arousal and stimulation continues, it is likely that the glans or head of the erect penis will swell wider and, as the genitals become further engorged with blood, their color deepens and the testicles can grow up to 50% larger. As the testicles continue to rise, a feeling of warmth may develop around th... |
Monday Mysteries | Crime and Punishment | The most famous painting in the world, the [Mona Lisa](_URL_3_), was involved in the most famous theft in modern art history, the theft of 1911 (and its implications were quite humorous).
On August 20, 1911, [Vincenzo Peruggia](_URL_0_), who was posing as an employee in the Louvre, hid overnight in the museum and walked out with the famous painting the next day (he served 7 months in jail for this famous theft). There are a couple theories on the motivation, which are summarized on the wikipedia article.
The more interesting aspect is that [Guillaume Apollinaire](_URL_4_), a famous writer and art critic, was implicated in the theft. Furthermore, Apollinaire implicated [Pablo Picasso](_URL_1_) as an accomplice. Apollinaire and Picasso, though day did not commit the theft, were terrified of being questioned *because they were in possession of stolen works from the Louvre*. Specifically, some stolen Iberian masks, which Picasso would paint in his [Les Demoiselles d'Avignon](_URL_2_). Picasso received these Iberian masks from a mutual friend of Apollinaire. This incident prompted Picasso to return the masks to the Louvre, and he was never charged with any crime. | [
"The story takes place in 1894, three years after the death of Sherlock Holmes. On the night of March 30, an apparently unsolvable locked-room murder takes place in London: the Park Lane Mystery, the killing of the Honourable Ronald Adair, son of the Earl of Maynooth, a colonial governor in Australia. He was in his... |
what about a glass ketchup bottle makes it so difficult to easily pour? | The ketchup is thick enough to create an air tight seal at the neck of the bottle.
In order for ketchup to leave the bottle there needs to be airflow to replace the ketchup.
Unless the bottle is plastic so you can squeeze and reduce the volume of the container without needing air to replace the ketchup. | [
"The relatively high viscosity and thixotropic nature of ketchup can make pouring it from a glass bottle somewhat difficult and unpredictable, and several urban legends surrounding this phenomenon have arisen. According to one popular folk remedy, repeatedly hitting the \"57\" mark on a glass Heinz ketchup bottle m... |
elf on the shelf | It's an elf doll that comes with a story. In the story it explains that each Elf is given magical powers once its family names it. Your children then name it. Once that is done, only grown-ups can touch the Elf or it will lose its powers. The story goes on to say that every night your Elf now uses its magic to fly back to the North Pole and report on who is being naughty and nice. In the morning the Elf usually lands in a different place around the house, so the kids go find him every morning.
For the parents, you just have to remember to move it every night. I kinda dig the Elf on the Shelf personally. | [
"\"The Elf on the Shelf\" was written in 2004 by Carol Aebersold and daughter Chanda Bell over a cup of tea. Bell suggested they write a book about an old tradition of an elf sent from Santa who came to watch over them at Christmas time. Aebersold's other daughter, Christa Pitts, was recruited by the family to shar... |
why do products say "may contain eggs"? they either do or don't contain eggs, right? | My understanding is this. It's a liability thing. If at some point during the manufacture or packaging of their product it comes in contact with eggs or egg residue, and someone then has an allergic reaction to it, then the company is covered because they said it may contain eggs. | [
"Unlike many products, trademarks and advertisements for egg brands are usually printed on the food container itself rather than on a separate container (as with breakfast cereals). This single-layer, distinctive packaging distinguishes egg cartons from different producers or quality on the retail shelf.\n",
"The... |
With a laser pen, why can I see the dot of light but not a beam behind it? | You can only see light that directly enters your eye. The beam of the laser isn't pointed at you, so none of the photons are hitting your retina. The dot, however, is a results of photons from the beam reflecting/scattering off of some object, and many of them scatter in your direction and hit your retina, which is why you see it.
For certain wavelengths of lasers (e.g. green) the beam will scatter off particles in the air and hit your retina, which is why the beam is visible. But for a red laser, the wavelength is too long for it to scatter much in the atmosphere. | [
"Laser scanners work the same way as pen-type readers except that they use a laser beam as the light source and typically employ either a reciprocating mirror or a rotating prism to scan the laser beam back and forth across the barcode. As with the pen-type reader, a photo-diode is used to measure the intensity of ... |
why does fine powder (like flour or powder milk) mixes evenly when stirred in cold water, but not in hot water (where the mixture becomes lumpy)? | Most powders dissolve better in hot water because the molecules of water have more energy and are "bumping" into the powder molecules. Hot water molecules have more energy and move more than cold molecules.
In some powders, mostly those that contain starches, the rapid mixing of the powder and hot water becomes a problem. The hot water immediately bonds with the outer layer of the bits of powder, but they form a shell which prevents water from reaching the subsequent layers of powder. | [
"To analyze a grain sample it first needs to be ground to a powder; a flour sample can be analyzed as is. The sample is put into the test tube; distilled water is added, and the tube is then shaken vigorously to achieve a homogeneous mix. The tube is then placed in the boiling water bath, and the operator begins to... |
is cancer just bad luck? for instance how can someone that never smoked get lung cancer, but another one that does never gets it? | At the end of the day luck is a large factor, however it's not truly random chance. Kind of like how getting struck by lightning is random (bad) luck, but if you walk around during thunderstorms with a giant metal pole you'll be increasing your chances.
Likewise, random mutations resulting in cancer that isn't snuffed out by the body is random chance, but there's countless things that increase your risk factors of developing cancer. Such as frequent/excessive exposure to sunlight damaging the skin, inhaling carcinogens and the smoke itself damaging lung tissue, etc etc etc. | [
"Results from epidemiological studies indicate that the risk of lung cancer increases with exposure to residential radon. A well-known example of source of error is smoking, the main risk factor for lung cancer. In the West, tobacco smoke is estimated to cause about 90% of all lung cancers. \n",
"15% of lung canc... |
Who was filming WW2 and why? | In the United States at least, the US government was backing it. Hollywood directors such as John Huston and John Ford volunteered for service with the military (Army, and Navy, respectively), where their talents were put to the best use, namely making movies. They, and others, were tasked with creating films for domestic consumption to bring the war home to American audiences, in other words, propaganda. Ford, for instance, shot the film "Battle of Midway", during the fight itself, although in part it was sheer luck he was present, the Navy having already sent him there to shoot more tranquil footage. He recalled the irony afterwards that "“I think at the time there was some report of some action impending but [...] I didn’t think it was going to touch us. So I [...] spent about 12 hours a day in work, had a good time up there.”
By far most famously though was D-Day. The Allies intended to thoroughly document their triumph there, and several hundred ships were equipped with movie cameras, as were some 50 landing craft, all constantly rolling and not needing human touch. In addition, Ford was tasked, along with George Stevens, were given film crews and sent on in with the troops, part of a documentary force that numbered in the hundreds when you include still photographers (Ford was attached to the Navy and OSS, Stevens to the Army, and coordinated very little). Stevens would land on Juno Beach with the British, while Ford landed on Omaha, where the most intense fighting was. He would actually refuse to talk about it for many years after, but did eventually offer his recollections:
> Once I was on the beach I ran forward and started placing some of my men behind things so they’d have a chance to expose their film. I know it doesn’t sound blazingly dramatic. [....] To tell the truth I was too busy doing what I had to do for a cohesive picture of what I did to register in my mind. We stayed on the job and worked that day and for several other days and nights too.
Ironically, for all their efforts, almost none of the footage was released, as the camera crews had not held back in the slightest from showing the horrors of war. After being processed in London a few days later, at least according to Ford "[a]pparently the government was afraid to show so many casualties on screen." It was not entirely lost though. Those familiar with the story from Stephen Ambrose's book on D-Day will likely only know the conclusion at that point, when no one knew where the footage was still, but since that time, some of it was, in fact, rediscovered in US government storage. What of the footage has so far been released, however, I can't say off hand. Edit: See brief addendum in [this comment](_URL_0_). A bit of poking around would indicate the surviving footage is still quite limited, but still more than nothing!.
Anyways though, that is just a very small slice of this, and other countries no doubt had their own way of doing this, but with the US at least, the power of Hollywood was put at the beck and call of the military, and used to provide documentation of the fighting. "Five Came Back: A Story of Hollywood and the Second World War" by Mark Harris is a book on the topic, focusing on Ford and Huston, as well as Frank Capra, George Stevens, and William Wyler, who were also involved in the war effort.
Edit: I was able to find an extensive interview by Ford given in 1964 which expands upon the above quotations. He was speaking with Peter Martin, and it was published in The American Legion Magazine, Volume 76, No. 6 (June 1964):
> "How would I describe my job?" John Ford said, when I asked him. "Unofficially, I was in charge of cinemaphotography, but in all honesty I was really more or less a logistic officer. It was up to me to see that everybody who should have a camera had one. I take my hat off to my Coast Guard kids. They were impressive. They went in first, not to fight, but to photograph. They went with the troops. They were with the first ones ashore. They filmed some wonderful material. Fortunately, most of them came through well. There were a few casualties. I lost some men. It is a coincidence that one of the cameramen who works for me today — his name is Archie Stout — had a son in my outfit. He was one of the two photographers who rode ashore on a Phoenix concrete breakwater. He rode his Phoenix all the way over from England photographing everything in sight. He did a fine job riding that big box. He got a Silver Star for it. Later, he was to be flown back to England to sign his papers for a commission for which he certainly qualified in every way. On his way, even before he'd left France, a lone German fighter popped out of nowhere and shot him down. He's buried there in a cemetery where the landing was. That cemetery was a new one and Stout's was one of the first graves there. I've been back to it several times to leave flowers.
> "I think it's amazing that I lost no more, when you consider how much some of them were exposed to fire, although I wouldn't let them stand up. I made them lie behind cover to do their photographing. Nevertheless, they didn't have arms, just cameras, and to me, facing the enemy defenseless takes a special kind of bravery. When a man is armed with a gun he's probably much braver than if he doesn't have one.
> "In action, I didn't tell my boys where to aim their cameras. They took whatever they could. Once they got ashore they just started photographing our troops in different groups rushing to their assigned places. Not that they rushed wildly, they rushed with a definite purpose. After they got ashore, they made for a certain objective. There was no panic or running around. I've often wondered why they didn't run faster. Probably they weighed too much with all their equipment on. They hurried, but there was no frantic dash, just a steady dogtrot.
> "I remember meeting Col. Red J. Reeder on the beach. I knew him well and I met him a long time later when I went to West Point to do a picture. The Long Gray Line. On D-Day, Red was sitting with one leg smashed so badly it had to be amputated. 'Got any orange juice?' he asked me. I said, 'Orange juice! What the hell would I be doing carrying orange juice? How- about a shot of brandy?' We had been issued little bottles of brandy in case anybody needed it. Doggedly he said, 'No, I want orange juice.' I said. Colonel, I'm afraid that's something I can't get you, but I can help you get back to our ship which is close in. Once there you can get some aid.' He said, 'No, I just want some orange juice.' Red and I had a laugh about that long afterward at West Point. In a moment of crisis, people get funny fixations. I asked him, 'Why didn't you take that brandy?' He said, i don't know. It's the first time in my life I ever refused a drink of hard liquor. All of a sudden I was pure. As a matter of fact, I don't even like orange juice.' He was in shock, and as I've said, they had to cut off his leg in an emergency operation.
> "The film my men took was processed in London, in both color and black-and-white. Most of it was in Kodachrome. It was transferred to black-and-white for release in the news weeklies in movie theaters. All of it still exists today in color in storage in Anacostia near Washington, D.C. My cutting unit was in London, too. They worked 24-hour watches, picking out the best part of the film that had been shot. I'm sure it was the biggest cutting job of all time including the cutting done for the recent picture Cleopatra. The cutters worked four-hour shifts — on four, off four. Allen Brown, the producer, now a captain in the Reserve, was in charge. There were literally millions of feet of film. When Brown's unit saw something they liked, they pressed a button, and put clips on that portion of film. When they cut the stuff all they did was cut at the places marked by those clips. It saved a lot of time. Very little was released to the public then — apparently the Government was afraid to show so manv American casualties on the screen. After all. even The New York Times best-seller list that summer had only six 'war books' on it out of a total of 30.
> "As I've said, I don't think I ever saw more than a dozen men at one time on that beach. That's all my eye could take in. For that matter. I don't think any- body on the beach saw more than 20 at the outside. After all. they all were at- tacking in small groups. They were trained to do that. The first wave consisted of about 3.000 men. and not all of them got ashore alive. Numerically, that wasn't so many really.
You can find the full interview [here](_URL_1_).
| [
"The film documents Britain's military preparedness, showing scenes of the army and navy in preparation for war, and the manufacture of munitions. The film was made by the Cinema Committee, comprising Charles Urban, William Jury of Jury's Imperial Pictures and Tommy Welsh of Gaumont, at the behest of the covert Bri... |
how ducks not freeze in cold water in winter | They are surrounded by a thick layer of fat under the skin, and an insulating layer of downy feathers over the skin. So they are highly insulated. | [
"The ducks face very different environmental conditions depending on the location of their wintering grounds, which affect their migratory behavior. Higher proportions of males have been located in the northern part while more females and juveniles winter in the southernmost portion of the range. In spring, males a... |
health care individual mandate vs. car insurance mandate | It seems like you're trying to make a political point, rather than asking a question, but requiring car drivers to have car insurance is categorically different from requiring *all citizens* to have health insurance. The roads belong to the state, and people agree to follow the states rules in order to get the states permission to use them. There is no act of agreement between nondescript citizens and the state when it comes to health insurance, however. In other words, if you don't want car insurance, then you can not drive on the public's roads, though if you don't want health insurance, there's nothing lawful you can do.
This is why some people oppose a mandate when it comes to health insurance. | [
"Usage-based insurance (UBI) also known as pay as you drive (PAYD) and pay how you drive (PHYD) and mile-based auto insurance is a type of vehicle insurance whereby the costs are dependent upon type of vehicle used, measured against time, distance, behavior and place.\n",
"Telematic usage-based insurance (i.e. th... |
Why do people here not think that B12 gives you more energy? | Ok so I have studied the effects of both B12 and Vit D at length because I am deficient in both and am going into nursing so it was part of my schoolwork. If someone has therapeutic levels of B12 then a B12 supplement will do little if anything for energy levels. This is the case with most vitamins. Your body has an optimum level that it uses the vitamins to catalyze actions but above that there is no bonus. But B12 absolutely is involved with energy levels. A deficiency in B12 will cause a ton of problems including lethargy and fatigue. In those cases, which are not only caused by pernicious anemia, there is a noticible boost in energy. It is also important to note that the expected levels of vitamins are averages for what most people need. Even if you test at the low end of normal for B12 levels, you may still be deficient, although your doc may not say you are.
Now gets more into supposition from the research I am done, and I am on my phone so I can't cite sources. B12 comes from a bacteria that grows on vegitation. In the US we wash the vast majority of our vegitables so we clean off B12 on those. That means our main source of B12 is from animals that eats vegitation with B12 on them. The problem is that much of the livestock in the US is corn or grain fed, including beef and poultry, and doesn't have high B12 intake. That means, absent fortified foods, the US diet is deficient in B12. In the northwest, where I have seen the most numbers as it is where I live, there is a large percentage of the population that is low-normal or deficient in B12, which means many people will benefit from a B12 supplement. It all depends on your diet and food sources. I know for myself, I am severely deficient although I don't have pernicious anemia, and have to have regular B12 shots and take daily supplements. I find that there is no harm, given the rate of B12 deficiency, to recommending a supplement or at least seeking out fortified foods in the diet. It may do nothing if you don't need it, but can make an enormous difference if you happen to be deficient and the cost is low as is risk.
I know many people will disagree with me on some of this, but these are the facts as I know them for my region. Every region will also differ in rates of deficiency due to availability in the food supply. I wont even go into Vit D definciency for the northern states and canada, as it is another wall of text on its own but also plays a huge role in pain experience and energy level. | [
"This interest may have been sparked because of the existence of nanomachines such as ATP synthase (adenosine triphosphate), which is the “second in importance only to DNA”. ATP is the main energy converter that our bodies contain and without it, life as we know it would not be able to flourish or even survive.\n",... |
if my pet has fleas, how come they don't infest me too? | They can, but generally they prefer certain types of animals over us, just like it's possible to give a dog head lice, but unlikely. | [
"Flea infestations can be not only annoying for both dogs and cats and humans, but also very dangerous. Problems caused by fleas may range from mild to severe itching and discomfort to skin problems and infections. Anemia may also result from flea bites in extreme circumstances. Furthermore, fleas can transmit tape... |
How closely related (in time and in substance) are the myths of the ancient world? | Better answers are coming, but I'll try and point you in the right direction for some information.
As far as Northern India, Greece, and Rome are concerned, they're descendent from a group of people known as "proto indo-europeans", originally from the Black Sea.
_URL_0_
They share cultural, religious, and linguistic similarities. I can't remember all the sound changes, but the words for god are more or less the same in the languages, though the specific meaning of the word might be slightly different.
I'm not going to say much more because it's been a while since I've studied historical linguistics, but that should get you started.
| [
"In contrast, the myths of many traditional cultures present a cyclic or static view of time. In these cultures, all the \"[important] history is limited to a few events that took place in the mythical times\". In other words, these cultures place events into two categories, the mythical age and the present, betwee... |
How were memorials designed for world wars? | Oh my gosh! This is my *thing!* I have some things already written on it that I sent to a friend recently, and I'll do my best to amend them to reflect your teacher's points and your question.
Your teacher was probably referring to a notion sometimes held by modern historians and art historians that creating a metaphorical representation of tragedy is difficult because any metaphor associated with a tragedy is ruined by association with it, and does not do any actual good as a piece of art in remembrance of the loss. In my experience, this view has been best expressed by Jay Winter, the editor of the most recent edition of the Cambridge Histories of the First World War. Winter has written several books about memorialization of the Great War, including "Sites of Memory, Sites of Mourning" and "Remembering War," in which this idea appears. He usually applies the idea your professor was talking about specifically in terms of the Holocaust, discussing the difficulty of creating an effective Holocaust museum without lessening the tragedy or misrepresenting loss. However, the idea that it's difficult to make a meaningful memorial to such a large loss is quite applicable to many other things as well. I've studied the application of the idea specifically to Great War memorials, so that's what I'm going to talk about in answer to your main question about how memorials are designed.
One of the reasons that memorials sometimes fail is that experiences with huge wars are *extremely* personal: no two neighborhoods, divisions, or even soldiers will have experiences that can be captured meaningfully by the same piece of artwork. (See Winter's "Sites of Memory" for more on the individualization of loss in the Great War.) As such, the most effective memorials are often those created by people who have been effected by the conflict which they are memorializing. In the Great War, Britain's Foreign Office operated a propaganda unit called Wellington House, and several notable artists of the period were dispatched by it to the Western Front to create sketches and drawing of the War (see most any cultural history of the War for more info on this highly interesting project; I like Robb's "British Culture and the First World War"). Some of these artists had already been veterans themselves, discharged for minor injuries. Other veterans actually created artwork while still at the Front, or at least began to create it; there's an artist named Eric Kennington who claimed to have created an oil-on-glass portrait while carrying the work from location to location on the Front (this has been pretty heavily disputed, and I haven't found evidence of it in his archives, but he definitely did make it within a month or two of his discharge at the latest). When the War was over, these veteran artists were often either hired by the government or took up private commissions to create memorials, and their artwork is some of the most striking post-war memorial work done after the Great War. (See ERIC KENNINGTON 1917-1918 on microfilm in the War Artist's Archive, Imperial War Museum London, Scates and Wheatley on War Memorials in the Cambridge Histories, Winter's Sites of Memory and the FANTASTIC "The Great War in Modern Memory" by Paul Fussell for more about either Kennington, the war artists, or the memorials they made).
Differences in the memorials made by affected artists and those less affected by the War are many and varied, but I'll try to give a rundown of a few major ones here. Please note that these characteristics are not by any means limited to memorials created by veteran-artists -- I'm just arguing that they are *more likely* to be seen in memorials created by those who fought or were personally affected by fighting.
- Pre-Great War memorials rarely showed individual infantrymen, preferring to focus on the glory of generals and other commanders. Post-War memorials were more likely to depict individual soldiers, the rank and file of the War.
- Some church memorials attempted to avoid showing visions of damaged human bodies or war images in favor of a more sanitized memorial listing names and commending souls to God. Veteran-artist memorials almost always show actual human figures, often armed, if not actually wounded.
- The absence of almost all writing on memorials was a trend that emerged around this time and became quite popular as a memorial response to the Holocaust; Winter argued that removing imagery from a memorial and leaving a huge, blank chunk of stone was a way to physically represent a "hole" in society that was impossible to close. I would argue that memorials with lots of writing do this less effectively than huge memorials with very little text.
I hope this has helped! If you want to look them up, some of my favorite memorial sites are London's Cenotaph, the Machine Gun Corps Memorial at Hyde Park Corner, and the 58th London Division Memorial at Chipilly, France. All of those sites have characteristics of veteran memorials such as those I described above.
**In short, I suppose the answer to the question "how were memorials designed" by my understanding is that these veteran-artists did their best to recreate their experiences in artwork!** I believe that answer applies to the Second World War as well.
*Edit:* Lest my words be misinterpreted, I want to emphasize that what is considered a "good" memorial will change drastically from person to person, and historian to historian. The factors I described about how better Great War sites were designed by artists are by no means exhaustive or definitive. They are just my opinions based on my reading and research :) | [
"Most World War I war designers attempted to produce memorials that were, as cultural historian Jay Winter describes, noble, uplifting, tragic and endurably sad. There were various architectural styles used on memorials, but most were essentially conservative in nature, typically embracing well established styles s... |
atomic and hydrogen bombs in space. | The main difference between the effects of an atomic bomb detonated in space and that on the ground are not related to gravity, but are related to the fact that the bomb is going off without an atmosphere (air) around it. When a bomb goes off, a lot of the energy is released as thermal and ionizing radiation (heat radiation and nuclear radiation). In an atmosphere (that is, relatively near the surface of the Earth or on it), a good amount of that energy is immediately absorbed into a shell of air surrounding the bomb. This super hot shell of air then bursts out, causing the well-known pressure (blast) effects of the bomb — the stuff that knocks down houses and smashes everything.
In the absence of an atmosphere, the heat and nuclear radiation are not as dissipated, and the blast pressure is much more muted. As a result, a nuclear weapon detonated in space is mostly heat and nuclear radiation, and both of those effects go further than they would on Earth, because they are not being absorbed by any atmosphere.
The other main difference is that the electromagnetic pulse effect of the bomb, which is relatively limited at near-surface altitudes, can go much, much further and be much more powerful. This can disable satellites and even certain types of electrical circuits on Earth, over a very wide area.
As with all high airbursts, there would be no local nuclear fallout. The radiation, however, can linger in space for a long time, which has implications for satellites and radio communications.
There would be no mushroom cloud, which is a function of the fireball being in an atmosphere as well. (The fireball is hot and less dense than the atmosphere, so it rises. The movement of a less dense substance through a dense one produces the familiar mushroom-cloud appearance.)
Gravity has no effect on allowing the blast to expand or compressing it. It is too weak a force to affect that. It is not possible to make a black hole from a nuclear explosion; black holes are formed by putting _lots_ of matter into one place. A nuclear explosion does not do anything like this. | [
"Scientists initially considered using a hydrogen bomb for the project, but the United States Air Force vetoed this idea due to the weight of such a device, as it would be too heavy to be propelled by the missile which would have been used. It was then decided to use a W25 warhead, a small, lightweight warhead with... |
what ever happened to all those cash for gold companies? | _URL_0_
The value of gold was climbing until 2012, when the market suddenly trended downwards, and it's predicted to get worse. Since gold isn't as valuable anymore, there's less incentive to run a business that collects it.
| [
"BULLET::::- Cash for gold – With the rise in the value of gold due to the financial crisis of 2007–2010, there has been a surge in companies that will buy personal gold in exchange for cash, or sell investments in gold bullion and coins. Several of these have prolific marketing plans and high value spokesmen, such... |
why is it easier to gain fat than to loose it? our body reacts when we eat too much, why dosen't it do the same when we try to loose fat? | It used to be harder to gain fat when we used to live in caves and had to run from predators on a regular basis. | [
"Ordinarily, the body responds to reduced energy intake by burning fat reserves and consuming muscle and other tissues. Specifically, the body burns fat after first exhausting the contents of the digestive tract along with glycogen reserves stored in liver cells and after significant protein loss . After prolonged ... |
what are you thinking before developing language ? | Babies/infants learn through patterns, noises, and repeated stimuli, all by closely watching their environment. Babies of only a few days old understand depth perception and a few months in, they can count and understand so-called “impossible events” (term coined by child psychologists).
One such example is having a baby watch a diorama of a toy mouse walking through a house; the toy was moved by a researcher and visible through windows. The wall facing the baby was moved to show a researcher placing a wall between the 2 windows, and the same scene was put back together and shown. There were 2 mouse toys now which showed what appeared to be identical to the first scene without the wall. The babies always showed shock/amazement when the same mouse was shown walking continuously through the wall which supports the theory that babies are born to acquire innate instincts and a rudimentary understanding of physics.
As for how they think, or in what quasi-language, some researchers think it’s largely done by pattern, association, and images. Learning via pattern is, after all, how infants learn language in the first place.
Source: took child & developmental psychology courses in college | [
"Language development is thought to proceed by ordinary processes of learning in which children acquire the forms, meanings, and uses of words and utterances from the linguistic input. Children often begin reproducing the words that they are repetitively exposed to. The method in which we develop language skills is... |
what would time dilation feel like? | You wouldn't perceive time slowing down. That is the entire basis of relativity, that no matter what constant speed you move at, light moves at the same speed relative to you. This is the basis of all the math, which came to include time dilation. So if you are standing still relative to earth or moving at 0.99999c you will experience time the same | [
"A strong time dilation effect has been reported for perception of objects that were looming, but not of those retreating, from the viewer, suggesting that the expanding discs — which mimic an approaching object — elicit self-referential processes which act to signal the presence of a possible danger. Anxious peopl... |
how the us justice system handle rape accusations? | Well it depends.
If you are a politician, then the accuser has their life turned upside down and is often accused of being a slut (even by the politician's wife). Or if you are a beloved famous personality then you are simply ignored unless enough people complain that it can reach a "news media critical mass" and start to stick.
If you are a college student or a normal career minded male, then your life is utterly destroyed. | [
"Rape charges can be brought and a case proven based on the sole testimony of the victim, providing that circumstantial evidence supports the allegations. It is these strict criteria of proof which lead to the frequent observation that where injustice against women does occur, it is not because of Islamic law. It h... |
Does a fetus feel pain? | It is awake and moving quite a bit by the second trimester. There's no reason it wouldn't once the nociception system is established. | [
"A meta-analysis of data from dozens of medical reports and studies that fetuses are unlikely to feel pain until the third trimester of pregnancy. There is a consensus among developmental neurobiologists that the establishment of thalamocortical connections (at weeks 22-34, reliably at 29) is a critical event with ... |
does the time warner cable/charter merger violate anti-trust laws? | Anti-trust laws give the Department of Justice the authority to make that call. It is decided case-by-case by the courts.
The Antitrust Division of the Department of Justice did indeed file a lawsuit arguing against the merger. In court, "New Charter" agreed to a list of concessions and regulations in order to complete the merger, most related to net neutrality. New Charter agreed to keep with the regulations and the DOJ agreed to let the merger go through. | [
"Citing the reduction of competition in the broadband and cable industries that would result from the merger, the Department of Justice planned to file an antitrust lawsuit against Comcast and Time Warner Cable in an effort to block it. On April 24, 2015, Comcast announced that it would withdraw its proposal to acq... |
What is the theoretical maximum to how many liters/second over a region of rain can fall during a storm? | There is a theoretical limit (though that varies depending on the temp other atmospheric conditions). And that theoretical limit is based on the density of water and laws of buoyancy as they pertain to water. Its a pretty complex calculation. | [
"Storms which have moved slowly, or loop, over a succession of days lead to the highest rainfall amounts for several countries. Riehl calculated that 33.97 inches (863 mm) of rainfall per day can be expected within one-half degree, or 35 miles (56 km), of the center of a mature tropical cyclone. Many tropical cyclo... |
What exactly does your body do to your brain when you have ALS? | Your motor neurons die in that disease. This subset of nerve cells are what's used for movement throughout your body.
For the most part, not a lot happens in the brain itself in ALS, so although primary motor neurons in the CNS are killed off too, diagnostics mostly focus on abnormal motor control, abnormal reflexes, and abnormal muscle contraction. | [
"The defining feature of ALS is the death of both upper motor neurons (located in the motor cortex of the brain) and lower motor neurons (located in the brainstem and spinal cord). In ALS with frontotemporal dementia, neurons throughout the frontal and temporal lobes of the brain die as well. The pathological hallm... |
the story of the soviet union | This is one of my favorite topics, because it allows me to expand on a couple points.
The first is exactly how bad things were in Tsarist Russia. Russia was one of the last honest to god Feudal societies on Earth. They had actually progressed past this earlier, but then reverted. The Serfs were considered literal property of the land-owner whose estate they were born on. Those born on Imperial land were State-owned. This ended in the 1860's, and the resulting situation wasn't much better. Think Jim Crow laws on steroids, and applied to everyone who wasn't a noble or aristocrat.
The second is how wildly successful communism was. Don't consider this an endorsement, it's just a statement. It took the society I just described and by 30 years on had created one of two super powers the world has ever known, with mastery of the atom and a space program. Think of it like the dinosaurs- They may have died off, but they shaped, and dominated, the world. Indeed, the Twentieth Century can be seen as the story of the Soviet Union. America's adventure in Vietnam was a direct response to Soviet activity fostering an uprising in the country. Osama bin Laden got his start in the Mujaheddin, an American-funded guerilla force put forward to hinder and ideally end the Soviet occupation of Afghanistan. The Soviet Army (and Soviet winters) are a large (possibly largest) tangible contribution to Hitler's downfall in WW2. We went to the moon not for any specific reason, but to make sure we beat the Soviets there. Many of the international organizations began as a way to facilitate communication between the Soviets and the West.
Communism failed, and the Soviet Union collapsed. I'm of the mind that Communism will always collapse under its own weight eventually. Others differ in their opinion of that. But it's hard to overstate just how much influence the Soviet Union had on the world we know today. | [
"The series began with a scenario of what the writers believed might occur should the United States fall to the Soviet Union. After this, the series took a historical approach, giving brief biographies of Karl Marx and Lenin, and depicting Joseph Stalin's rise to power. The series climaxed with an edition about the... |
How were epic poems interpreted in their time? | I can't speak for any of the Classical Epics but Beowulf was certainly more than pure entertainment. Although written in the eighth century (NB There is much disagreement over this) the practices and events in the epic pre-date it by far. Arguably, Beowulf is an origin myth - a strange amalgamation of true historical events and mythical characters. For example, that King Hygelac was killed in an ill-fated raid on Frisian shore (lines 1204-1216) is backed up by several other sources, including the Gregorii episcopi Turonasis Historia Francorum (History of the Franks) by Gregory of Tours. Hygelac (whom he calls Chlochilaichus), he says, won a battle at Ravenswood in 510AD before being killed attacking the Frisians in 521AD. Similarly, on examining family trees of major houses, like the Wuffing house (Potentially the family of Sutton Hoo) mention many of the kings of Beowulf. Some of the major characters, such as Hrothgar also recur within other contemporary texts such as Widsith and the Norse Sagas. There is evidence to suggest that Hrothgar, Ongentheow, Haethcyn, Onela and Heardred were all historical characters. Perhaps the most notable name we find in Beowulf is that of Hengest. Hengest, who succeed Hnaef as leader of the Half-Danes avenges his death by killing fin, king of the Frisians. This Hengest, who appears in the Finnesburgh Fragment is quite possibly the same Hengest who came to England in 449AD at the request of King Vortigern in order to fight the Picts; the same Hengest who, as reported in The Anglo-Saxon Chronicle, then performs a treacherous volte-face, turning on Vortigern and the Britons before founding the kingdom of Kent. This Hengest would, to the Anglo-Saxons, be a legendary figure of huge interest, comparable only perhaps to the American Founding Fathers or of the titular character of the Aeneid.
So, I would argue that although, of course, Beowulf is a guide on heroism and kingship, it is also a socially binding origin myth for the Scandinavian migrants that settled Britain. First and foremost, however, as an oral composition (which it most likely is), its primary function must be seen as entertainment. I hope this answered at least part of your question! | [
"Famous examples of epic poetry include the Sumerian \"Epic of Gilgamesh\", the ancient Indian \"Mahabharata\" and \"Rāmāyaṇa\", the Tamil \"Silappatikaram\", the Persian \"Shahnameh\", the Ancient Greek \"Odyssey\" and \"Iliad\", Virgil's \"Aeneid\", the Old English \"Beowulf\", Dante's \"Divine Comedy\", the Finn... |
What is the academic consensus on Stephen Turnbull's claim that Ninjas never existed? | Turnbull's work on the ninjas, and their historicity, has come up here more than once before, While you're waiting for fresh answers to your question, you might like to review [this earlier thread](_URL_0_), led by u/NientedeNada, which contains links to the most important of these discussions and assessments. | [
"Despite many popular folktales, historical accounts of the ninja are scarce. Historian Stephen Turnbull asserts that the ninja were mostly recruited from the lower class, and therefore little literary interest was taken in them. The social origin of the ninja is seen as the reason they agree to operate in secret, ... |
Are there any places on the planet that have had massive issues due to rising sea levels, or has it not got to that point yet? | [The Maldives in the Indian Ocean.](_URL_0_) 80% of the country is less than 1 meter above mean sea level. Very small changes in mean sea level mean big areas of inundation. | [
"Ten per cent of the world's population live in coastal areas that are less than above sea level. Furthermore, two thirds of the world's cities with over five million people are located in these low-lying coastal areas. Future sea level rise could lead to potentially catastrophic difficulties for shore-based commun... |
I'm looking for more information on carthaginian political factions during the first punic war (reading recommendations)? | There isn't much good material on the Carthaginians which makes writing about them a challenge. The only sources we have for them are Roman and Sicilian, and they both hated Carthage. A book you might be interested is *Carthage Must Be Destroyed* by Richard Miles. He discusses the political factions of Carthage. | [
"BULLET::::- Hamilcar Barca, Carthaginian general who has assumed command of the Carthaginian forces in Sicily during the last years of the First Punic War with Rome, helped Carthage win the Mercenary War and brought extensive territory in the Iberian Peninsula under Carthaginian control (b. c. 270 BC)\n",
"BULLE... |
why do certain animals mainly appear when it begins to rain? | Can you give an example of the types of animals you're thinking of?
Often snails and such come out because it's wet and they can range further without drying out.
Worms come out for similar reasons and because their burrows sometimes fill with water.
What specific animals were you thinking of? | [
"The likeliest explanation for many of the supposed cases is that there is no falling happening at all and the animals are driven along by winds or a deluge of some sort. This explanation also accounts for the prevalence of reports that only a single species or type of animal is ever reported raining from the sky.\... |
how did we come to the conclusion that gravity has the same speed as light? | We measured it.
By which I mean we measured both the gravity and light coming off a stellar collision and found that the difference could be explained by the vacuum of space being very slightly imperfect so the light wasn't going at the speed of light in a vacuum, while the gravity was.
Since the collision happened 130 million lightyear away/years ago and the light and gravity arrived only 1.7 seconds apart, there really isn't any better explanation available than that they were going at basically the same speed. | [
"Albert Einstein went through several versions of light speed theory between 1905 and 1915, eventually concluding that light speed is constant when gravity does not have to be considered but that the speed of light cannot be constant in a gravitational field with variable strength. In the same book Einstein explain... |
why does foam act like a solid when it is made of just liquid and gas? | A balloon behaves like a solid ball, but it's mostly air. Foam is just a big pile of tiny balloons made of soap. | [
"Foam, in this case meaning \"bubbly liquid\", is also produced as an often-unwanted by-product in the manufacture of various substances. For example, foam is a serious problem in the chemical industry, especially for biochemical processes. Many biological substances, for example proteins, easily create foam on agi... |
If the colors we see are just the wave length of light that is not absorbed by the object, int he absence of light is everything the same color? | It'd look black under that light. The lack of color/light is black. It means your eyes/detector isn't getting any signal.
Also, real shirts aren't perfect absorbers/diffuse reflectors, you'd still "see" the shirt, it wouldn't be a void in your perception, but it wouldn't look blue simply because they're no blue light around. | [
"Up to this point white objects have been discussed, which do not absorb light. But the above scheme continues to be valid in the case that the material is absorbent. In this case, diffused rays will lose some wavelengths during their walk in the material, and will emerge colored.\n",
"As the order of the optical... |
why is apple the most valuable company in the world? | You reap extremely high profits when you charge $3,000 for $500 of hardware and people keep buying it because it's pretty and white.
I'll be down at the bottom in a few minutes for my factual, but unpopular opinion.
Regardless, if I could do 1998 over again, I'd have invested everything I made in Apple stock. | [
"Apple is well known for its size and revenues. Its worldwide annual revenue totaled $265billion for the 2018 fiscal year. Apple is the world's largest technology company by revenue and one of the world's most valuable companies. It is also the world's third-largest mobile phone manufacturer after Samsung and Huawe... |
Did Arab expansion into the Mediterranean in the 8th and 9th century cause the central authority of the Carolingians to dissolve into a fragmented and feudal society? | Pirenne is at this point incredibly outdated (he died in 1935 after all) and aside from the standard "Pirenne was wrong" moment in contemporary works (and virtually every economic history has one) is largely ignored.
The idea that the Carolingian period was economically stagnant has been discarded as more attention has been paid to both Mediterranean and North Sea trade. It is not recognized that Europe was never a "closed" economy as such, and in fact much interest is now being focused on the ways in which Western Europe encountered and was connected to the wider world via trade, travel, diplomacy, etc.
The standard works you want to look at are McCormick' *Origins of the European Economy* and Richard Hodges' *Mohammed Charlemagne and the origins of Europe: Archaeology and Pirenne thesis* (really anything by Hodges will be of use)
edit: As to why Europe become "feudal" (and what that actually might entail) and when this occurred, well that in of itself is a whole other can of worms that I am going to chicken out on and hope that one of my fellow flaired who spends more time post 900 will pick up the slack :)
| [
"The massive Islamic invasions of the mid-7th century began a long struggle between Christianity and Islam throughout the Mediterranean Basin. The Byzantine Empire soon lost the lands of the eastern patriarchates of Jerusalem, Alexandria and Antioch and was reduced to that of Constantinople, the empire's capital. A... |
has anyone thought to send a drone to scout north sentinel island? what are the ongoing studies conducted on the sentinelese if there are any? | The Indian Government recognizes the Sentinelese's desire to be left alone. They don't even try to prosecute them on the occasions they have killed trespassers to the island.
| [
"The 30th Reconnaissance Squadron operates RQ-170 Sentinels. This squadron, which is based at Tonopah Test Range Airport in Nevada, was activated on 1 September 2005. RQ-170 Sentinels have been deployed to Afghanistan, where one was sighted at Kandahar International Airport in late 2007. This sighting, and the Sent... |
what is fire actually doing to wood/paper/gasoline, etc? | The chemical bonds that hold the wood together release energy when they are broken. These bonds break apart at a high enough temperature, and their breakage yields more heat, which in turn breaks more bonds. It forms a chain reaction.
Once enough of the bonds are broken, the wood loses shape. Much of the wood is converted into gas, and it's physical remnants (ash) is just leftover carbon. | [
"Firewood is any wooden material that is gathered and used for fuel. Generally, firewood is not highly processed and is in some sort of recognizable log or branch form, compared to other forms of wood fuel like pellets or chips. Firewood can be seasoned (dry) or unseasoned (fresh/wet). It is generally classified as... |
why do cop cars not pull all the way over when giving a citation on a busy street? | As an emergency responder, the real reason is to put a physical barrier between the officer standing beside your window and traffic. You'll see firetrucks and ambulances do the same type of positioning when responding to an accident. | [
"BULLET::::- take-downs, which are typically mounted on the front of an emergency vehicle's lightbar. Take-downs are used on police cars to illuminate the interior of a vehicle immediately in front of the police car, such as a vehicle that has been pulled over after committing a traffic violation or while conductin... |
why can't i have a wild bird like a cardinal or a jay as a pet? | You can, but they are relatively rare and prefer being in the wild as opposed to other birds that you can buy at a pet shop that are happy in a cage. | [
"Despite its name, the Goliath birdeater only rarely actually preys on birds; in the wild, its diet consists primarily of other large arthropods, worms, and amphibians. However, because of its size and opportunistic predatory behavior, this species commonly kills and consumes a variety of insects and small terrestr... |
What exactly did cannons do in Napoleonic warfare? | Can you clarify your question? Do you mean “how did Napoleon use artillery effectively?”(tactics and strategy) “how do cannons help in war at the time?”(more of a mechanical question) or something else entirely?
The short answer is that what you’re describing isn’t particularly accurate of Napoleonic artillery usage. Napoleonic artillery usage piggybacked off of the reforms of Gustavus Adolphus in Sweden to lighten artillery substantially, mobilizing firepower on a greater scale than had been prior seen. This enabled him to group his artillery in grand batteries, and concentrate fire on high priority targets/restrict enemy movement. For much much more, see this detailed answer from /u/vonadler: _URL_0_ | [
"Artillery was the most devastating weapon on the field during the Napoleonic era, and its use could leave the enemy troops demoralized. Solid metal cannonball (also known as a \"round shot\") were commonly used artillery ammunition. They were effective against square formations and heavily packed columns when fire... |
the concept of light: its speed, how it travels, what it means to be "# light-years away", etc. | So, light travels at a speed of just about 300k km/s.
Light is photons, which are particles that have zero rest mass, and therefor moves at the speed of light (only massless objects can travel at the speed of light). Those particles travel like all other particles travel.
When something is a number of light-x away (so light-year, light-minute, light-second etc.) it's the distance light travels in that time. For example, the Sun is about 8 light-minutes away from the Earth, because it takes light 8 minutes to travel from the Sun to the Earth. | [
"The light-second is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in one second, and is equal to exactly .\n",
"The speed of light is (by definition) exactly 299,792,458 m/s, very close to 300,000,000 m/s. This is... |
If we can make amoxicillin taste like bubble gum, why can't we make all the other liquid medications taste good as well? | A lot of the time medications are formulated to have unpleasing tastes to avoid abuse. If OTC cough syrups containing DM tasted good, people would be using them to get effects similiar to PCP or Ketamine.
There is also of course the risk of a child overdosing, so that is another protectionary measure. If it tastes good, kids will eat it, too much of it, at once.
Thirdly, many medications have strong natural tastes inherent to their own chemical formula's, and all we can do is mask them. This has varying degrees of success, as you can't simply dilute them with flavour until they're no longer effective, nor can you add whatever flavour you like, as not everything will be compatible in suspension, syrup, or whatever formulation of medication happens to be being delivered. | [
"The flavorings are intended to improve the palatability of their host medications by suppressing bitterness, adding sweetness, and/or enhancing the flavor profile. The flavoring of liquid medicines using these products has been shown to improve pediatric drug compliance. The firm also sells Pill Glide, a flavored ... |
how did us mammals evolve into having emotions and specifically love? | Emotions evolved from communication. For example wolf who was able to bark when danger occured saved its pack members thus increasing it own chance of survival. Wolfs who didn't react / understand to react to danger more likely perished.
I think love is more primitive thing. It is just feeling that one should mate with another one. | [
"The study of the evolution of emotions dates back to the 19th century. Evolution and natural selection has been applied to the study of human communication, mainly by Charles Darwin in his 1872 work, \"The Expression of the Emotions in Man and Animals\". Darwin researched the expression of emotions in an effort to... |
Can a human body explode from being electrocuted? (cross post from /r/Askreddit) | This was queried here previously:
[_URL_0_](_URL_0_)
tl;dr - Not really. | [
"Electrical injury is a physiological reaction caused by electric current passing through the body. Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient magnitude of current to pass through the victim's flesh, viscera or hair. Physical contact with energi... |
Did "great warriors" exist? | No, they did not, but not for the reason you suggest.
It's always possible to give some examples of individual warriors who were famed for their exploits in hand-to-hand combat. But these exploits never live up to the standards of Hollywood movies. In most cases these "heroes" are said to have defeated just a few opponents. Part of the reason ~~Miyamoto Musashi~~ Yagyu Munenori was credited with absolutely legendary battle prowess was the fact that he once killed 7 men in a single engagement. This is a far cry from the carnage of most pre-gunpowder battle scenes in movies and TV series; for the heroes of the silver screen, 7 kills is a slow day in the tavern.
However, the reason for the difference isn't that the chaos of battle would kill anyone well before they could rack up a notable list of victories. The notion that battle is a maelstrom of intermingled fighters is itself a completely fictional Hollywood trope. Organised warfare was a matter of formations: all your friends on one side, all the enemy on the other. The role of the warrior in such a formation was to hold his place, not to try and kill as many enemies as he could. Disorder was a greater enemy than the enemy. Encounters between infantry formations were not chaotic but tentative and probing; only in certain circumstances would mass be pressed against mass, and even then there would be limited opportunity for single warriors to kill very many of the enemy.
In other words, on most pre-modern battlefields there just wasn't any room for "great warriors" of the Hollywood mould. In the heat of battle, the number of casualties would be relatively low. Most men in most battles would never kill anyone, and would be happy enough just to survive. In any case, the great majority of them would be stationed behind the first rank with no means of reaching the enemy even if they wanted to. In such battles, most of the casualties would come when one side broke and ran, and the other chased the fleeing troops to stab them in the back with impunity. But there was little skill involved in that bloody process, and no movie is likely to celebrate the act of murdering the defenceless.
But then why do we keep telling those stories? Why do TV shows, books and movies depict battle in this totally unrealistic way?
One thing is certain: it's not just about a modern thirst for visual spectacle. Stories about great warriors scything their way through hordes of enemies are as old as time. Homer's *Iliad*, one of the oldest surviving Greek texts, spends several chapters on the *aristeia* (Great Deeds) of individual warriors like Diomedes, Patroklos and Akhilleus. For these heroes, simply killing droves of human warriors isn't enough; with the help of Athena, Diomedes defeats both Aphrodite and Ares when they appear on the battlefield, and Akhilleus famously [takes on the river Skamandros](_URL_0_).
But when we turn to *historical* sources, there are no parallels. The *aristeia* of real Greek warriors during the Persian Wars speak only of men who won a single duel, or who simply fought in a memorable way, without anyone apparently caring how many they killed. Finally the tradition of awarding *aristeia* seems to disappear. We also find both Spartans and Athenians actively punishing people for leaving their place in the battle line to go and take some heads. As I said above, organised warfare just doesn't leave much room for men to play the hero.
But how do you inspire warriors to give everything they have for their commander and community, if you can't show them some great examples? Just standing in a line and not running away is hard enough for men who have never been in combat. Most men would not want to do anything more than that. But it won't be enough to win. You need men to be willing to go and stab a guy in the face, even if he's trying to stab them in turn. So what do you do?
The common answer given by Greek commanders was to show them how it was done. Alexander the Great is the finest (or most batshit insane) example of this method: in every one of his battles, he flung himself into combat with reckless abandon, inspiring his men to follow him. We never hear how many men Alexander personally killed, and it really doesn't matter. Even in one of his most memorable acts of recklessness, when he was the first to leap down from the wall into an enemy fortress, he killed just one man before another incapacitated him and his bodyguards had to come to his rescue. But the point is that they did. They were willing to fight because their leader was willing to fight; they were ready to die because they saw that their leader was ready to die. It was his ability to *inspire others* that allowed Alexander to win so many fights.
The reason for Hollywood to focus on the sheer lethality of its heroes, even at the expense of all realism, shows that this particular form of leadership still has some of its old magic. But we should not mistake those depictions for historical truth, any more than we should believe that Diomedes defeated the god of war in single combat. | [
"The Mighty Warriors is an anthology of fantasy short stories in the sword and sorcery subgenre, edited by Robert M. Price. It was first published in trade paperback and ebook by Ulthar Press in May 2018, and was a homage to the similar early sword and sorcery anthologies \"The Mighty Barbarians\" (1969) and \"The ... |
Do we know when Alexander the Great's sarcophagus was lost? | The latest mention of the body of Alexander comes from 215 under the emperor Caracalla. According to contemporary historians Cassius Dio and Herodian, Caracalla was obsessed with Alexander and had a strong desire to emulate the great conqueror. Herodian reports that Caracalla went to the tomb in Alexandria, opened up the sarcophagus, and placed his purple cloak and other assorted valuables inside. He then went back to his regularly scheduled business of massacring the Alexandrians because they weren't treating him with the respect he felt he deserved.
That is the last historical record of someone visiting the body of Alexander. What happened to it afterwards is a mystery. It is possible that the site was destroyed during Aurelian's campaign of 273 or that simple coastal erosion has consigned the tomb to the waves. However, mentions of a site alleged to be Alexander's tomb feature in later reports of Arab writers Ibn Abdel Hakam (A.D. 871), Al-Massoudi (A.D. 944), and Leo the African (sixteenth century). As mentioned in a piece on the subject in a publication for the Archaeological Institute of America (see [here](_URL_0_))all these accounts mention such a place but do not give its exact location. We can be reasonably certain that the tomb was in Alexandria and not Memphis, where it may have been originally following the body's arrival in Egypt in 321 BC. Ptolemy II (or perhaps Ptolemy I) moved the body to Alexandria in the early third century and the body was probably moved again later on by Ptolemy IV.
Despite the mystery that pervades this subject, there has been no shortage of effort expended on finding the tomb of Alexander. The medieval accounts mentioned above may well reference the real tomb and plenty of people have spent a lot of time and money trying to find it. Some 140 officially recognized attempts to find the site have been mounted over the years but with no success. A popular local legend states that the tomb lies below or near the Nebi Daniel mosque but it's not clear what evidence, if any, this supposition relies on. It may well be little more than nineteenth century romanticism. A team of Polish researchers working in the 1960s determined that the network of tunnels underneath the mosque were ancient cisterns rather than any kind of tomb. People still believe the legend though and subsequent, but fruitless, excavations have since taken place at the mosque. Other researchers of lesser repute have posited various alternative theories about the tomb's location but with little solid evidence.
The sum total of all this is that we don't really know what happened to Alexander's sarcophagus and tomb after the visit of Caracalla in 215. Coastal erosion may well have swallowed up the site but the fact that the location is so uncertain leaves us without a definitive answer. It may have been destroyed by Aurelian's war in 273 but we cannot say for sure. It is plausible that some or all of the later accounts refer to the real tomb and that it was still around by as late as the 16th century but specific details are lacking. Lots of people have looked for it without success but this is no deterrent for the most determined. No one has found any record of Alexander's earlier resting places either. In any case, Alexander's body has been an item of intense interest to a lot of people for over 2300 years (a war was fought over its custody after all) and this interest shows no sign of letting up.
For more see the article referenced above and *The Quest for the Tomb of Alexander the Great* by Andrew Chugg. | [
"While Alexander's funeral cortege was on its way to Macedon, Ptolemy seized it and took it temporarily to Memphis. His successor, Ptolemy II Philadelphus, transferred the sarcophagus to Alexandria, where it remained until at least late Antiquity. Ptolemy IX Lathyros, one of Ptolemy's final successors, replaced Ale... |
Long Roman names | There's not a ton of mystery in the name here, even if Q. Sosius Priscus' name takes the practice to its extreme. Unusually long names in consular families in the second century is rather well attested epigraphically, though you wouldn't know it at all from reading the actual texts, the authors of whom almost without exception keep the names short, even when they're known to be longer. The imperial family is of course the best example of this practice: compare, already in the mid-first century, Claudius' full name with his usual moniker in Suetonius and Tacitus of just "Claudius" or "Caesar." The strict "tria nomina" that people are taught in Latin class is, epigraphically, rather less common than might be supposed. In the late Republic the use of multiple cognomina was quite common, and for a brief few decades the use of archaic praenomina was revived amid a general devaluation of the praenomen that continued into the Principate, during the course of which it eventually disappeared entirely. By the early second century we see in particular a rise in what's called "binary nomenclature," which is basically people whose names are composed of two full names. So Pliny the Younger's full name is basically two names, C. Plinius L.f. Oufentina Caecilius Secundus, where L.f. and Oufentina are just parental indicators (so his name is typically written C. Plinius Caecilius Secundus, where Plinius and Caecilius are both nomina). A number of factors resulted in these names and names like them. Mommsen found that in the Principate a new practice was added to testimentary adoption, which had been rather poorly regulated in the past (see, for example, the weirdness of Brutus' name), and to maternal inheritance, that the benefactor's name be added to the recipient's. If you break apart Q. Sosius Priscus' name it's pretty easy to understand, actually. The version you print here is not actually his name, as recorded on his epitaph, which includes the filials Q.f. and Quir(ina). Sosius' name, a good chunk of which came from his father, is clearly the result of maternal inheritance and testimentary adoption over the course of at least three generations but it's a very traceable set of names. Morris was able to trace these names back to about a dozen people going back about a century, whose complex web of inheritances had eventually converged on Sosius and his father. | [
"An amount of names from Roman times has also survived until today, many of them being Roman versions of former Greek or Thracian ones. Some Latin names had fallen into disuse long ago, but were revived in the 20th century. Examples: Montana, Lom (a Slavicized version of Latin \"Almus\"), Archar (a Slavicized versi... |
What part of a flame transmits the most heat? | It depends on the flame/fuel source. For the most part, sustained flames use a gas fuel source and there's a section called a hydrogen cone. For Bunsen burners this is the tight, light blue cone that rests between two darker blue cones.. it's almost clear in color. | [
"A flame (from Latin \"flamma\") is the visible, gaseous part of a fire. It is caused by a highly exothermic reaction taking place in a thin zone. Very hot flames are hot enough to have ionized gaseous components of sufficient density to be considered plasma.\n",
"The hot-blast design, also known as a \"tubular l... |
what makes people smile/frown or do any facial expressions connected to how they feel the same way everywhere? is it biological or just years of people doing that with their faces? | Both.
Biologically, the human brain is well-adapted to notice, understand, and use these physical cues. The human body is well adapted to actually displaying a smile/frown (and other common expressions).
With that said, our instinct to do this is reinforced by other people we’re around— this is actually a method of communication and using body language in a way that feels “natural” and is easy for other people to understand takes practice, just like spoken language does. | [
"Facial expressions are produced to express a reaction to a situation or event or to evoke a response from another individual or individuals. They are signals of emotion and social intent. People make faces in response to \"direct audience effects\" when they are watching sports, discussing politics, eating or smel... |
How can fish, starfish and simple sea slugs live at the depth of the Mariana Trench without being crushed alive when we have to build pressure-resistant pods just to descend a fraction of that depth? | The main thing that’s helps creatures like that is that they have no lungs. If humans went down that far our lungs would collapse. Gases can compress which is not good for staying alive. Not only do fish and such not have lungs they don’t have other gaseous cavities either.
At high enough pressures even certain organs and some proteins do not function so ‘normal’ fish can’t live there long. A lot of the strange creatures that live that far down are specially adapted to that pressure and we are still learning about them but it’s difficult because it’s hard to go down there and bringing specimens back up seriously damages them.
Overall gases compress and liquids do not nearly as much.
[more](_URL_0_) | [
"All the equipment maintaining the extreme pressure inside the Abyss Box weighs . The device will keep deep-dwelling creatures alive so they can be studied, especially regarding their adaptability to warmer ocean temperatures. Currently the Abyss Box houses only common species of deep sea creatures including a deep... |
what is the difference between homeopathy and naturopathic medicine? | Homeopathy is an alternative "medicine" that involves taking a substance that causes a symptom, diluting it in water until zero molecules of the original substance remain (for the standard "30c" dilution, you would have to drink enough to fill the entire volume of the observable universe to get a single molecule).
Somehow this is supposed to cure the symptom the original ingredient caused. So if you had a headache, you'd use a substance that gives you headaches.
Naturopathy is a blanket term for a variety of alternative medicines, including homeopathy but also acupuncture, herbalism, and other stuff that isn't pills and doesn't work. | [
"Naturopathy or naturopathic medicine is a form of alternative medicine that employs an array of pseudoscientific practices branded as \"natural\", \"non-invasive\", and as promoting \"self-healing\". The ideology and methods of naturopathy are based on vitalism and folk medicine, rather than evidence-based medicin... |
why does a rope..etc break when pulled suddenly(when hauling heavy weights),but holds if gradual force is applied? | F = ma, or Force equals mass times acceleration.
When you apply an acceleration to the rope by jerking it, it creates a force. The harder you jerk the rope, the greater the force. | [
"The load creates tension that pulls the rope back through the knot in the direction of the load. If this continues far enough, the working end passes into the knot and the knot unravels and fails. This behavior can worsen when the knot is repeatedly strained and let slack, dragged over rough terrain, or repeatedly... |
What kind of leader was/is Fidel Castro? It seems that every single documentary I see paints him in a different light - I'd like to get down to the truth. | Honestly, it seems as though you're pretty much answering your own question. As a historical figure, Castro is nuanced enough to be intriguing and, as you say, some of his policies appear laudable and others appear unpleasant.
Historians can offer multiple judgements, but it's really up to you - is democracy more important than good healthcare? And, more importantly, is this always the case, or is there a moment when the health system is good enough that you can prioritise democracy instead? Is democracy even a goal we should aim for?
If you care a lot about negative liberty, capitalism, or even just that there are limits to equality and state intervention, then Castro isn't going to look great. If you are a Communist of any stripe, or believe that the end can justify the means, or feel that equality and positive liberty are important goals, then he'll look a bit better.
For my two cents, democracy and liberty are a bit too nebulous to worry about. My problem with Castro is his suppression of political dissidents and active participation in a culture of homophobia. | [
"The Real Fidel Castro is a biography of the Cuban revolutionary and politician Fidel Castro, written by the British diplomat Sir Leycester Coltman (1938–2003) and first published by Yale University Press in 2003. A diplomat for the government of the United Kingdom, Coltman had been appointed to the position of Bri... |
what would happen to your eyes if you don't blink for 24 hours, 1 week, 1 month, 1 year? | I think the underlying question here is: why are eyeballs wet?
There are living cells on the surface of the eyes, and just like any other living cell they will die if the proper fluidity is not kept. Because human eyes aren’t hard, the surface must also be kept moist and smooth to avoid distorting the light that comes through it. | [
"Blinking results in blurred and incomplete image of the fundus. It is imperative to instruct the patient not to blink when the fundus photo is taken.The patient may blink normally at any other time to prevent the excessive drying of the eye. A dry eye may also lead to a blurred fundus photo. When dry eye is suspec... |
are there known evolutionary reasons that humans have a sense of aesthetics? ex. thinking that trees are beautiful, puppies are cute, art is beautiful, music sounds good, etc. | Several. The art and music builds group cohesion. You are attracted to your own group's art and music which makes you feel connected to other members of your group. Young animals and other "cute" species have facial proportions similar to our own young. We find our young cute so that we, you know, like them and that reaction is non-specific enough that it gets applied to other species. The tree thing isn't as well established, but generally speaking people feel more comfort/less stress in natural settings. This may have less to do with the natural settings per se and more to do with the fact we only started living in industrial settings very recently, which means they are lesd familiar to us than traditional natural settings. | [
"Human preferences toward things in nature, while refined through experience and culture, are hypothetically the product of biological evolution. For example, adult mammals (especially humans) are generally attracted to baby mammal faces and find them appealing across species. The large eyes and small features of a... |
can someone out there please explain to me what's the difference between a metaphor and an analogy? | **Then**
You can use it as a sort of "well in that case!" Like if someone's a jerk to you, and you say "Then piss off!" You're saying "Well, in that case, piss off!"
But more appropriately it's used as a time reference, and it can be done in two ways: sequentially or contextually.
In sequence: "I'm going to do this. Next I'll do this other thing. Then I'll do that."
In context: "When I was nine years old, blah blah blah. I was living at that address, then."
**Than**
A word used to introduce the next part of something you're comparing. "I'm smaller than you." You're the second piece of my "compare these two things," where I'm the first.
It's also used to follow some other word when trying to offer some "exception to the rule," such as in "I like women other than your mom." As your mom was bad in bed, I wanted to exclude her from the women I like. | [
"A metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another. It may provide (or obscure) clarity or identify hidden similarities between two ideas. Metaphors are often compared to other types of figurative language, such as antithesis, hyperbole, metonymy and si... |
Does "spaghettification" really not occur at super massive black holes? | For supermassive black holes, the point at which the tidal forces become so strong that they spaghettify you indeed lies inside the event horizon. So the spaghettification would happen after you enter the black hole.
_URL_0_ | [
"In astrophysics, spaghettification (sometimes referred to as the noodle effect) is the vertical stretching and horizontal compression of objects into long thin shapes (rather like spaghetti) in a very strong non-homogeneous gravitational field; it is caused by extreme tidal forces. In the most extreme cases, near ... |
Why did large numbers of people still emigrate to the United States despite the ongoing War for Southern Independence? (1861-1865) | …. Alright I’ll take the bait. Yes, the “War of Southern Independence” is one of the many names that have been used to designate the conflict between the Northern and Southern United States from 1861-1865, more commonly known as the American Civil War. It is, however, a loaded term, which you knew when you inserted it into your question and were likely looking for a fight on that topic anyway.
Contemporary and current constitutional interpretation holds that the United States, from both 1776 and 1789, was a compact between the thirteen former British colonies turned states and the subsequent states and territories added on to the Union from the years 1789 to 1861. These “add-ons” included both Northern (Ohio, Michigan, Wisconsin, etc.) and Southern (Mississippi, Alabama, Texas, etc.) states. By entering into this compact/social contract, these constituencies implicitly renounced their sovereignty in place of a federal constitutional union. To secede from that Union, even for the auspices of forming your own, independent republic (ie, the Confederacy), is to break up the compact as a whole, and, thus, constitutes a Civil War. Contrary to Southern propaganda (and, fairly, some Northern and Western propaganda as well) the United States Founding Fathers did not believe in the rights of the states to secede, as demonstrated by the trials of Aaron Burr and his associates for their attempts to break off portions of the Union in the early 1800s. Furthermore, they inserted no clause into the Constitution creating a mechanism for secession, nor was any subsequent amendment passed allowing it. This was finally codified, albeit after the Civil War, in the Supreme Court case of Texas v. White, 74 US 700 (1869), which held that the state of Texas, and thus all former confederate states, had never left the Union, and that secession is inherently unconstitutional.
Now, that is not to say that the Southern states did not have a natural right to secede, merely that the constitutional argument upon which secession was initially based was flawed. Appealing then to natural laws, as the founders did, Southerners could (and did, and do) lay claim to Lockean theories of a people’s right to rebel against unjust or unrepresentative government. This was precisely the argument taken in 1776 by Jefferson, Adams, and Franklin et al in Philadelphia:
> That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness. Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed. But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.
In 1861, many southerners explicitly referred to the “Spirit of 1776” as a motivator for their rebellion, claiming their rights, liberties, and privileges had been trampled upon in the same manner, or worse, as their great-grandparent’s had. If you hold that the southern states had really suffered “insufferable evils” at the hands of the federal government – of which, it should be noted, they were a voting and fully represented constituency, unlike their 1776 forbears – then perhaps this “long train of abuses and usurpations” (1861 edition) could in fact justify a separatist movement, and thus the long-hoped for “War of Southern Independence.”
However, I take issue with that interpretation as well. The Southern states, rather than being an oppressed accessory to le madre patria as the North American colonies were to Great Britain, were in fact the dominating force of American politics and government from the founding of the republic to 1860. Look at the Presidents elected during those years. Without exception they were Southerners or southern sympathizers. Congressional allotment due to the three fifths clause, and the democratic inequality inherent in the US Senate, allowed them to dominate the Congress, and their justices comprised a majority of the Supreme Court throughout the time period. Time and again, Southern legislators and Southern Presidents enacted legislation suiting their sectional interests, as any dominant party would do in a fractured national government. As the Northern states’ populations grew however, by the 1850s Southerners began to recognize that their national dominance would come to an end. The breakup of the Whig Party in 1852, and the subsequent formation of the entirely Northern, anti-slavery Republican party in 1854, and its impressive second-place showing by candidate John C. Fremont in the 1856 Presidential election, only confirmed those fears. In response, Southerners grew increasingly bellicose, and at the election of the first northern President completely un-beholden to the Southern aristocracy’s interests (that is, the preservation and expansion of slavery) in 1860, Southerners called for a dissolution of the Union that they had previously dominated less than a decade earlier, under the pretense that they were an oppressed group whose rights were suddenly being trampled upon. The argument is as dubious today as it was back then, and people recognized it. Lincoln in his first inaugural at several points referenced this:
> Physically speaking, we cannot separate. We cannot remove our respective sections from each other, nor build an impassable wall between them. A husband and wife may be divorced, and go out of the presence and beyond the reach of each other; but the different parts of our country cannot do this. They cannot but remain face to face, and intercourse, either amicable or hostile, must continue between them. Is it possible, then, to make that intercourse more advantageous or more satisfactory after separation than before? Can aliens make treaties easier than friends can make laws? Can treaties be more faithfully enforced between aliens than laws can among friends? Suppose you go to war, you cannot fight always; and when, after much loss on both sides, and no gain on either, you cease fighting, the identical old questions as to terms of intercourse are again upon you.
> This country, with its institutions, belongs to the people who inhabit it. Whenever they shall grow weary of the existing government, they can exercise their constitutional right of amending it, or their revolutionary right to dismember or overthrow it. I cannot be ignorant of the fact that many worthy and patriotic citizens are desirous of having the National Constitution amended.
And he concluded:
> In your hands, my dissatisfied fellow-countrymen, and not in mine, is the momentous issue of civil war. The government will not assail you. You can have no conflict without being yourselves the aggressors. You have no oath registered in heaven to destroy the government, while I shall have the most solemn one to "preserve, protect, and defend it."
In his second inaugural he summed up the same point more succinctly:
> On the occasion corresponding to this four years ago, all thoughts were anxiously directed to an impending civil war. All dreaded it—all sought to avert it. While the inaugural address was being delivered from this place, devoted altogether to saving the Union without war, insurgent agents were in the city seeking to destroy it without war—seeking to dissolve the Union, and divide effects, by negotiation. Both parties deprecated war; but one of them would make war rather than let the nation survive; and the other would accept war rather than let it perish. And the war came.
As Lincoln was in 1861 I am loathe to close. But I will summarize with this: the phrase “War of Southern Independence”, while perhaps accurate in a sense, disguises the revolutionary nature of what was in fact a Civil War taking place in the United States from 1861-1865. That is, a revolutionary overthrow of an existing government and a battle for control of that government between rival sectional forces. Like Hitler’s “Lebensraum” or Kitchner’s “War to End Wars,” the “War of Southern Independence,” or my favorite the “War of Yankee Aggression,” are names designed to serve a political agenda rather than accurately describe the most momentous and important four years in the history of the United States.
And in answer to your original question, the US, even in 1863 in the midst of Civil War, had significantly greater opportunities for class mobility, largely due to the great swaths of land in the West that were still being developed compared to overcrowded Europe.
| [
"Many Southerners had lost their land during the war and were unwilling to live under the government of the United States of America. They did not expect an improvement in the South's economic position. Most of the emigrants were from the states of Alabama, Texas, Louisiana, Mississippi, Georgia, South Carolina, an... |
Do electrons "seem" to teleport when changing orbits due to acceleration to near light speed, resulting in time dilation? | Electron's don't have a well defined location. They don't orbit in circles around the nucleus. Instead, they exist in a "cloud", so to speak, of possible locations. When an electron gains energy, that cloud shifts to a higher energy configuration. But the electron doesn't jump from one place to another. We can't even really say if it's in once place or another. | [
"Suddenly displacing one of two gravitoelectrically interacting particles would, after a delay corresponding to lightspeed, cause the other to feel the displaced particle's absence: accelerations due to the change in quadrupole moment of star systems, like the Hulse–Taylor binary, have removed much energy (almost 2... |
What element/chemical would be extremely useful if it werent so dangerous to humans? | radioactive materials for sure
I would be rocking a nuclear laptop battery right now if it wouldnt melt my balls | [
"Experiments for human toxicology require a long term following and a large amount of investment in order to classify a chemical as co-carcinogens, carcinogens or anti-carcinogenic. In recent years, people substitutes health supplement for healthy meal. Some myths even state beta carotene as elixir in developing co... |
How do pockets of breathable air form in deep underwater caves? | The rock around those caves is mostly sandstone and limestone, both of which are permeable (notice all the stalagmites and stalactites in the images). To find air, all you would have to do is find a part of the cave above the water table, as the air would be able to seep through the rocks. As to how often the the oxygen gets replenished, I found [this article](_URL_0_) that says that the air tends to get swapped out of caves on Mallorca whenever the outside air temperature gets lower than the cave temperature. It also mentions that the water table level is connected to the tides there. So presumably as the tides rise and fall, there would be at least somewhat of a bellows effect, getting some new air, even if not from all the way from the surface. | [
"The cave passages in the park are said to \"breathe\" as air continually moves into or out of them, equalizing the atmospheric pressure of the cave and the outside air. When the air pressure is higher outside the cave than inside it, air flows into the cave, raising the cave's pressure to match the outside pressur... |
When did Constantinople spread to the opposite side of the Bosporus Strait? | Constantinople under Byzantium never made it to the other side of the strait. In fact the [Fatih](_URL_0_) district of Istanbul was the entirety of Constantinople until Ottoman conquest.
However, a little known fact is that Constantinople continued to be called Constantinople in many contexts (not all contexts; [other names](_URL_1_) were Konstantiniyye, Stamboul, Islambol/Islambul, and of course İstanbul) throughout Ottoman rule. So even though Byzantine Constantinople, the one you probably think about when you hear Constantinople, never reached the other side, Ottoman Constantinople did. [Kadıköy](_URL_4_) and [Üsküdar](_URL_2_), districts on the Asian side, were formerly rural outposts associated with Constantinople, but the courts of Constantinople extended their jurisdiction there well before the 20th century. The name of Constantinople became İstanbul in Turkey in 1923 and internationally in 1930.
But you may be asking about the city limits. In that case, the Asian side was not incorporated until the city's massive expansion, characterized by structural change in the 40s and 50s and much population expansion in the 60s and 70s and later. The [first suspension bridge](_URL_5_) across the strait was built in 1973.
Or are you asking when the Asian side of the Bosporus was first settled? In that case, Üsküdar and Kadıköy are both ancient, founded in the BC's by Greeks from Megara. Üsküdar was known as Scutari and Kadıköy as [Chalcedon](_URL_6_), and both were founded before Byzantion itself. Chalcedon is well-known for the theological [Council of Chalcedon](_URL_3_).
So in summary, the Asian side was settled first but when the European side gained prominence under the Romans it lost influence (with exception of the Council of Chalcedon). Constantinople under the Byzantines never spread to the opposite side, but Ottoman Constantinople's courts gained jurisdiction over the other side, which was nonetheless a pretty rural area. The city limits themselves expanded across in the mid-20th century, by which time the city had been renamed İstanbul, and the first suspension bridge across was built in '73. | [
"The strategic significance of the strait was one of the factors in the decision of the Roman Emperor Constantine the Great to found there in AD 330 his new capital, Constantinople, which came to be known as the capital of the Eastern Roman Empire. The expressions \"swim the Bosporus\" and \"cross the Bosporus\" we... |
if the troops in ukraine are not officially russian, why can't nato attack them and defend ukraine? | Ukraine is not a NATO nation. | [
"Russian officials denied reports that Russian military units were operating in Ukraine (see War in Donbass), claiming instead they had been sent on routine drills close to the border with Ukraine and crossed the border by mistake. On 28 August 2014 Dutch Brigadier-General Nico Tak, head of NATO's crisis management... |
What were Roman shields made of and how effective were they? | The squared shield in question is generally referred to as the *scutum*, although in Latin, *scutum* simply means “shield.” The *scutum* was carried by most legionaries and many auxiliary infantry throughout the Principate, and appears to have fallen out of use in favor of ovular shields sometime during the mid third century A.D., a period characterized by changes in the panoply of Roman infantry.
The *scutum* was constructed from planks of wood, assembled longitudinally and held together by glue. It was covered on both sides by linen or hide, as has been confirmed by the *scutum* recovered from Dura Europos in Syria. This linen or hide cover was typically painted, with designs ranging in elaborateness. In Late Antiquity, shield imagery reflected unit identity, a tradition which had it’s origins in the Principate. Further protection came from bindings, edgings of hide or bronze attached to the circumference of the shield. The *scutum* was carried by a single grip, protected by an iron boss (*umbo*), fixed to the front of the shield by a number of rivets. Although the exact size of the *scutum* is unclear, the *scutum* recovered from Dura Europos provides a generalization. Measuring three and a half feet high and sixteen inches wide, it is likely most *scuta* were around this size. It is worth noting that Roman shields from later periods were constructed similarly, as were the shields of their Germanic adversaries.
The size of the *scutum* would have provided comprehensive protection to a Roman soldier, especially when combined with armor and helmet. A *scutum* would thus have provided protection from sword and spear thrusts, and the use of formations such as the *testudo* and *fulcum* (in Late Antiquity) implies Roman shields were relatively impervious to ranged missile fire. Roman infantry (especially in the Principate, but throughout Late Antiquity as well) fought in close-order, and required shields that could sustain the shock of hand-to-hand combat. That said, our literary sources are silent on the “durability” of a shield, as they are in general unconcerned with technical details. Experimental archaeology offers much in our attempts to understand the practical effects of Roman equipment, yet even here we must be skeptical. We cannot truly replicate equipment such as shields in the *exact* manner as the Romans, nor can controlled tests recreate the combat situations such equipment saw, due in no small part to our uncertainty of the mechanics of Roman battle. Thus, while the *scutum* and other Roman shields were quite effective and reliable, it is unclear exactly how much “damage” a shield could have suffered whilst still remaining useable.
| [
"In prehistory and during the era of the earliest civilisations, shields were made of wood, animal hide, woven reeds or wicker. In classical antiquity, the Barbarian Invasions and the Middle Ages, they were normally constructed of poplar tree, lime or another split-resistant timber, covered in some instances with a... |
If electrons in a copper wire move slower than a human can walk, why do lights and other appliances switch on almost instantaneously? | When you turn on a switch, you don't need to wait for the electron at the switch to get to the lightbulb for the light to come on. There are electrons hanging out all throughout the circuit. Individual electrons move slowly, but all of them are moving, and when you turn on a switch the electron movement propagates at roughly the speed of light ~~the speed of sound~~. So, when you hit a switch, electrons that are already hanging out in/around the bulb start to move very soon after you throw the switch, causing the light to go on. | [
"Therefore, in this wire the electrons are flowing at the rate of . At 60 Hz alternating current, this means that within half a cycle the electrons drift less than 0.2 μm. In other words, electrons flowing across the contact point in a switch will never actually leave the switch.\n",
"Purely in terms of the tempe... |
How did honey become supersaturated in the first place? What do the bees do if they find their entire hive crystallized? | Supersaturation doesn't only occur through heating. Honey is made to have a lower water% through forced evaporation-- bees fanning the uncured not-supersaturated honey until it is the proper ratio. If there is no seed crystal introduced in this process of supersaturation (which is pretty rapid), then no crystals will form in most circumstances. The honey (now hygroscopic) is then capped to maintain the ratio.
Additionally, purer solutions form larger crystals--honey is a complex mixture, so I would imagine that it would take a long time to form large crystals, and humans store honey longer than bees do. | [
"Early forms of honey collecting entailed the destruction of the entire colony when the honey was harvested. The wild hive was crudely broken into, using smoke to suppress the bees, the honeycombs were torn out and smashed up — along with the eggs, larvae and honey they contained. The liquid honey from the destroye... |
We don't feel the earth spinning because it is constant. Yet it is fastest at the equator and gets slower as you move away from it. My question is how come no one ever notices the increase or decrease when traveling towards the equator or away from the equator? | The effect of the coriolis force is very small at "normal speeds but will actually make a difference in fuel consumption of airplanes travelling north/south for a few thousand miles.
The Earth's spin is VERY important for rockets. All the efforts of Space-X trying to land on the water (much more difficult than land) are to take advantage of the earths spin. | [
"Because of a planet's rotation around its own axis, the gravitational acceleration is less at the equator than at the poles. In the 17th century, following the invention of the pendulum clock, French scientists found that clocks sent to French Guiana, on the northern coast of South America, ran slower than their e... |
how does the universe have a predictable nature if all subatomic particles that constitute matter are completely random? where exactly does predictability come from in a physical sense? | Over a large enough scale, patterns emerge. For example, if I flip a coin, I have no idea if its going to land heads or tails. It is complete random if it is the only coin I look at. But if I flip 10 quintillion coins, I'm pretty damn sure 5 quintillion coins are going to be heads, and 5 quintillion coins are going to be tails (or its going to be close enough to 5 quintillion that it won't practically matter). | [
"There are two fundamental sources of practical quantum mechanical physical randomness: quantum mechanics at the atomic or sub-atomic level and thermal noise (some of which is quantum mechanical in origin). Quantum mechanics predicts that certain physical phenomena, such as the nuclear decay of atoms, are fundament... |
Why does the Rh Negative blood type persist? Isn't it genetically disadvantageous? | For clarity, the Rh blood group actually consists of about 50 different proteins, which [have been evolving in arrangement for quite a while](_URL_0_). The main one that we are concernd with medically is the D antigen since it is the most immunogenic (likely to result in an immune response). Before blood transfusions existed, the main impact Rh type had on human fitness was in cases of [hemolytic disease of the newborn](_URL_2_), which wouldn't have been a big issue in populations that were mainly D positive or exclusively D negative. The geographic and/or cultural isolation of historic human populations meant that most populations were homogenously positive or negaive for the D antigen, and therefore the variation between populations can be attributed primarily to genetic drift. [Here's more general blood group genetics background](_URL_5_) from /r/askscience.
Edit: The proportion of those silent alleles is high overall, but if you look at the actual protein coding [there are many ways to make a non-recognizable or only paritally-recognizable D antigen](_URL_1_). These non-positive alleles are [still fairly population specific](_URL_4_), suggesting that once a serologically negative allele develops there is no selection on the locus (an arguement for the genetic drift hypothesis). The RHD coding region has all the hallmarks of a [pseudogene](_URL_3_) in the making. | [
"According to a comprehensive study, the worldwide frequency of Rh-positive and Rh-negative blood types is approximately 94% and 6%, respectively. The same study concluded that the share of the population with Rh-negative blood type is set to fall further in the future primarily due to low population growth in Euro... |
how did words such as fuck, shit, etc. originate? | Those are both words with very old Germanic roots. They are related to the Dutch words fokken/fok (to breed/breeding) and schijt (poop). Yes they were probably normal words before they were curse words. | [
"The history of curse words and profanity was part of spoken words in medieval era. The word \"fuck\" was used in English in the fifteenth century, though the usage in earlier times of 13th century was not with abusive intent. The word \"shit\" is the oldest of words in use with early references found in German and... |
how cotton has different quality. | I work in Ag and just visited/toured one of the USDA cotton grading facilities. So I think I can answer this.
The cotton is graded based on standards set by the USDA. it is measured by color, fiber length and strength, and the amount of trash (plant debris).
These standards come from various facilities in the USA. I witnessed the process and it was quite interesting. They take samples of cotton and form them into squares called biscuits. They place 9 biscuits of the same grade in a box, where they are ordered from the lowest end of that grade's spectrum to the highest. These boxes are purchased and used as reference by cotton producers.
Most of the difference, when it comes to textiles, is because of thread count and brand.
On a cool side note: the actual variety "Sea Island Cotton" from Georgia is extinct. All cotton produced under that name now is a different variety, but is still called Sea Island Cotton due to a legal technicality. I got to see a sample of *actual* Sea Island Cotton on display at the facility. | [
"Today, cotton is classed based on its measurements for fiber length, strength and length, micronaire (a measure of the cotton's fineness), color grade, color reflectance, color yellowness, and trash percent area.\n",
"Cotton classing is the measuring and classification of cotton by its specific physical attribut... |
what does ios do differently to android for iphones to only need 1-2 gb of ram? | Eyy I actually know the answer to this one (game & app developer with low-level expertise in power and memory management - lots of iOS and Android experience and knowledge).
---
Android was built to run Java applications across any processor - X86, ARM, MIPS, due to decisions made on the early days of Android's development. Android first did this via a virtual-machine (Dalvik), which is like a virtual computer layer between the actual hardware and the software (Java software in Android's case).
Lots of memory was needed to manage this virtual machine and store both the Java byte-code and the processor machine-code as well as store the system needed for translating the Java byte-code into your device's processor machine-code. These days Android uses a Runtime called ART for interpreting (and compiling!) apps - which still needs to sit in a chunk of memory, but doesn't consume nearly as much RAM as the old Dalvik VM did.
Android was also designed to be a multi-tasking platform with background services, so in the early days extra memory was needed for this (but it's less relevant now with iOS having background-tasks).
Android is also big on the garbage-collected memory model - where apps use all the RAM they want and the OS will later free unused memory at a convenient time (when the user isn't looking at the screen is the best time to do this!).
---
iOS was designed to run Objective-C applications on known hardware, which is an ARM processor. Because Apple has full control of the hardware, they could make the decision to have native machine code (No virtual machine) run directly on the processor. Everything in iOS is lighter-weight in general due to this, so the memory requirements are much lower.
iOS originally didn't have background-tasks as we know them today, so in the early days it could get away with far less RAM than what Android needed. RAM is expensive, so Android devices struggled with not-enough-memory for quite a few years in the early days, with iOS devices happily using 256MB and Android devices struggling with 512MB.
In iOS the memory is managed by the app, rather than a garbage collector. In the old days developers would have to use alloc and dealloc to manage their memory themselves - but now we have automatic reference counting, so there is a mini garbage collection system happening for iOS apps, but it's on an app basis and it's very lightweight and only uses memory for as long as it is actually needed (and with Swift this is even more optimised).
---
**EXTRA** (for ages 5+): What does all this mean?
Android's original virtual machine, Dalvik, was built in an era when the industry did not know what CPU architecture would dominate the mobile world (or if one even would). Thus it was designed for X86, ARM and MIPS with room to add future architectures as needed.
The iPhone revolution resulted in the industry moving almost entirely to use the ARM architecture, so Dalvik's compatibility benefits were somewhat lost. More-so, Dalvik was quite battery intensive - once upon a time Android devices had awful battery life (less than a day) and iOS devices could last a couple of days.
Android now uses a new Runtime called Android RunTime (ART). This new runtime is optimised to take advantage of the target processors as much as possible (X86, ARM, MIPS) - and it is a little harder to add new architectures.
ART does a lot differently to Dalvik; it stores the translated Java byte-code as raw machine-code binary for your device. ~~This means apps actually get faster the more you use them as the system slowly translates the app to machine-code. Eventually, only the machine code needs to be stored in memory and the byte-code can be ignored (frees up a lot of RAM).~~ ([This is Dalvik, not ART](_URL_0_)). Art compiles the Java byte-code during the app install (how could I forget this? Google made such a huge deal about it too!) but these days it also uses a JIT interpreter similar to Dalvik to save from lengthy install/optimisation times.
In recent times, Android itself has become far more power aware, and because it runs managed code on its Runtime Android can make power-efficiency decisions across all apps that iOS cannot (as easily). This has resulted in the bizarre situation that most developers thought they'd never see where Android devices now tend to have longer battery life (a few days) than iOS devices - which now last less than a day.
The garbage collected memory of Android and its heavy multi-tasking still consumes a fair amount of memory, these days both iOS and Android are very well optimised for their general usage. The OS tend to use as much memory as it can to make the device run as smoothly as possible and as power-efficient as possible.
Remember task managers on Android? They pretty much aren't needed any more as the OS does a fantastic job on its own. Task killing in general is probably worse for your phone now as it undoes a lot of the spin-up optimisation that is done on specific apps when they are sent to the background. iOS gained task killing for some unknown reason (probably iOS users demanding one be added because Android has one) - but both operating systems can do without this feature now. The feature is kept around because users would complain if these familiar features disappear. I expect in future OS versions the task-killers won't actually do anything and will become a placebo - or it will only reset the app's navigation stack, rather than kills the task entirely. | [
"The release of iOS 13 will be exclusively for the iPhone and iPod touch, as the iPad will branch off into a new iOS based operating system named iPadOS. Similarly, iPadOS will also drop support for iPads that have less than 2 GB of RAM, such as the iPad Air, iPad mini 2 and iPad mini 3.\n",
"The iPad was release... |
Does the way food looks and smells influence taste? If so how does that work? | By 'taste' I assume you mean the slightly more specific 'flavour' which is absolutely influenced by smell - studies have shown that, by removing the sense of smell via a nose plug, peoples' ability to identify what they are eating by taste alone is actually quite poor (for example, Mozel et al., 1960, or Murphy & Cain, 1980). One that I found interesting in these studies was coffee; participants had about a 90% accuracy rate in identifying coffee when they could taste it and smell it. When they could not smell it, identification dropped to under 5%. Also, in something like a car crash, the neuronal axons going through the cribriform plate (i.e. the neurons carrying olfactory (smell) information to the brain) can break - this results in a loss of smell perception, but also reduces the enjoyment that people get from food, since the flavour isn't as strong. In terms of 'how does that work?' I'm afraid I can't help you much there - I studied taste and smell, but we didn't really go into the mechanics of the interaction between the two other than 'they do interact'. | [
"The basic tastes contribute only partially to the sensation and flavor of food in the mouth—other factors include smell, detected by the olfactory epithelium of the nose; texture, detected through a variety of mechanoreceptors, muscle nerves, etc.; temperature, detected by thermoreceptors; and \"coolness\" (such a... |
why do people (even i) think that extremely attractive women are dumb? | For a long time intelligence in women was not considered an attractive quality, because of the shitty way that they were often treated in society. Intelligent women were often pissed off about being restricted from engaging with many roles or aspects of society, which meant they were less likely to be 'fun', so a lot of intelligent women hide the fact they are smarter than a large portion of the population (male and female).
You could also say a lot of men are intimidated by women of intelligence out of feelings of insecurity, so women who they felt intellectually superior to were considered attractive (even if they were faking it).
There's also the theory that extremely attractive women are handed everything from a young age and are never given the impetus to develop their intellects, and as such end up having limited education/critical thinking skills. Watch almost any interview with a famous model/actor/singer/sportsperson of either sex who made it big before the age of about 20 or so and cringe as they say the stupidest things imaginable.
All of these things set up cultural associations linking the idea that attractive women are unlikely to be intelligent. | [
"According to Alice Echols, \"Carol Hanisch ... argued that looking pretty and acting dumb were survival strategies which women should continue to use until such time as the 'power of unity' could replace them.\"\n",
"Traditional stereotypes of women make them out to be much more emotional and irrational than men... |
Can single celled bacteria get cancer? | No, because cancer is defines as abnormal growth of cells inside of a multicellular organism.
A 'cancerous' single cell organism just.. doesn't make sense. Maybe in a colonial organism, but that's not a truly independent cell.
A cancer is just a single cell mutation where in a single cell line tries to grow and multiply uncontrollably. This is only important in a larger organism, for a single celled creature this is normal life. | [
"In the process of the treatment, cancer cells are most likely to evolve some form of resistance to the bacterial treatment. However, being a living organism, bacteria would coevolve with tumor cells, potentially eliminating the possibility of resistance.\n",
"In addition to viruses, certain kinds of bacteria can... |
What i´m doing when I treat y´ as dy/dx ? | Most people would tell you that dx and dy are limits of small variations; you take a small difference, keep track consistently of terms that are of comparable size, and get proceed with your limits, etc.
However, there is a way to understand that the kind of manipulation you enage in above is correct *as is*. There is a way to formulate calculus using what is known as *non-standard analysis*, in which you extend the real numbers by adding in new objects, namely infinitesimals, and then see how you have to extend the number system if you include these objects plus the usual operations (addition, division, etc.). You get a new system of numbers, the hyperreals, and they contain the usual real numbers, plus infinitesimal and infinite objects. [Robinson](_URL_1_) showed that you can then perform the manipulation of infinitesimals in a mathematically rigorous way (your *dx* and *dy* are such infinitesimals), and showed too that the theorems and results of the ordinary approach to calculus are true for functions over the hyperreals. So when you perform the kinds of manipulations you describe in your question, you can understand that as performing a calculation using non-standard analysis, the ultimate result of which will reproduce a result that would follow (with more elaborate work) in the conventional limit approach to calculus.
A text that develops calculus in this way is Keisler's, which is found [here](_URL_0_). | [
"Pardoprunox acts as a D (pK = 8.1) and D receptor (pK = 8.6) partial agonist (IA = 50% and 67%, respectively) and 5-HT receptor (pK = 8.5) full agonist (IA = 100%). It also binds to D (pK = 7.8), α-adrenergic (pK = 7.8), α-adrenergic (pK = 7.4), and 5-HT receptors (pK = 7.2) with lower affinity. Relative to other ... |
What is happening, physically and computationally, to my computer as it degrades over the years? | A lot of people are giving very valid answers about software bloat, disk fragmentation, and so on. These are the most likely culprits. However, I wanted to add a few points about how physical hardware can degrade. Modern hardware is becoming increasingly sophisticated at dealing with marginal conditions which may impact performance before it fully fails.
First, and most common, consumer harddrives have roughly a three year expected lifetime. The failure distribution follows a bathtub curve. The bad units fail quickly in the beginning, then they tend to fail less frequently until the three year point where there is a sharp uptick. They also don't always fail suddenly and spectacularly. They can accumulate bad sectors and mask them by expensive remapping which creates an effect similar to fragmentation. They can have recoverable bit errors that consume a significant amount of time while the firmware processes ECC. If there are questionable sectors that are necessary for the operating system to function or boot you may periodically hit one and wait seconds for the firmware to recover the data.
Processors also have become increasingly heat aware. If your fans are full of cat hair and your motherboard is covered in dust the processor may throttle itself to stay within an acceptable heat window. The same may be true for high end graphics cards. Both now do a kind of automatic overclocking when conditions permit. | [
"In 2013, it was observed that shortly after the startup process, Automatic Updates (codice_2) and Service Host (codice_3 in Windows XP would claim 100% of a computer's CPU capacity for extended periods of time (between ten minutes to two hours), making affected computers unusable. According to Woody Leonhart of In... |
Why does the air within the Troposphere not settle and form layers out of its constituents? | For the same reason that the gases don't form an thin condensed layer on the ground: their thermal energies give them large velocities that promote mixing. It's a tradeoff between gravity and entropy. Gravity is the driving force pulling the atoms toward the ground; entropy is the driving force for random arrangements of various gases. And in contrast to liquids, there's no advantage for like molecules to be adjacent, because there's no intermolecular bonding in gases. So each type of gas trails off in pressure with a characteristic decreasing rate with altitude; simultaneously, the gases all coexist at low altitudes.
Now, to be sure, there's some enrichment of heavier gases at loower altitudes, and relatively heavy molecules like carbon dioxide are relatively (sometimes [fatally](_URL_0_)) enriched compared to the lighter molecules.
This effect is independent of convection (though convection also plays a part in mixing). Nitrogen and oxygen in a closed isothermal container don't separate either. | [
"The up and downdrafts of boundary layer convection is the primary way in which the atmosphere moves heat, momentum, moisture, and pollutants between the Earth's surface and the atmosphere. Thus, boundary layer convection is important in the global climate modeling, numerical weather prediction, air-quality modelin... |
Can astronomers find and study planets that are far away from stars or other natural space light sources? | Yes, but only under extremely rare circumstances given our current technology. One example is [PSO J318.5-22](_URL_0_), another example is [2MASS J1119-1137](_URL_1_).
Both of these objects are large planets, about 5 - 10 Jupiter-masses. They're also both very close, only about 80 light-years away. Finally, they're also both very young - about 10 million years, some 400x younger than our Solar System.
Most important for detection, they're both still hot from their original formation; in fact, we can only detect them because they're warm enough to emit their own infrared light, similar to the way the coils in your toaster glow red-hot. As they age, they'll cool, emit less and less infrared light and eventually fade from view.
So, in order for us to see one of these rogue planets, they need to be emitting enough of their own infrared light. That means they need to be...
- Hot enough to emit a lot of infrared light
- Young enough to still be hot
- Large enough that they don't lose that heat too quickly
- Relatively close to see them in spite of their intrinsic faintness | [
"Planets are extremely faint light sources compared to stars, and what little light comes from them tends to be lost in the glare from their parent star. So in general, it is very difficult to detect and resolve them directly from their host star. Planets orbiting far enough from stars to be resolved reflect very l... |
how do stealth planes & drones actually work ? | Stealth aircraft use two main techniques for avoiding radar detection: Using radar-absorbing materials and having certain angles of outer surfaces to reflect radar waves away from the receiver.
Radar works by sending out an electromagnetic signal out into the air. Those electromagnetic waves hit aircraft and are bounced back to a radar receiver. The size and location of that aircraft is calculated based on the waves that are reflected by the aircraft from the emitter to the receiver.
If you build an aircraft out of material that absorbs rather than reflects radar waves, those waves can't return to the receiver and give information on its whereabouts. Also if the radar waves hit the surface of the aircraft and are deflected upward or anywhere other than the direction of the receiver, the radar station does not have any information on where it is.
So using visible light as an example. Let's say you have a searchlight looking for aircraft at night. What you would do is build an aircraft that is black so a lot of visible light is absorbed and not reflected. Then you also design the surface of the aircraft to reflect what light isn't absorbed away from the eyes of the searchlight operator. No light returning to the eyes of the searchlight operator means he cannot see the aircraft. The same principle works with radar. | [
"The drone can loiter autonomously at high altitudes performing real-time, high-resolution intelligence, surveillance and reconnaissance (ISR) with its SAR and EO sensors. When a target is identified, it will either illuminate the target with a laser designator for other strike aircraft, or descend to lower altitud... |
- if foxes are canines too, can dogs theoretically create offspring with them? why or why not? | From Wikipedia:
> Members of the dog genus Canis: wolves, domestic dogs, dingoes, Ethiopian Wolves, coyotes, and golden jackals cannot interbreed with members of the wider dog family: the Canidae, such as South American canids, foxes, African wild dogs, bat-eared foxes or raccoon dogs; or, if they could, their offspring would be infertile.
> Members of the genus Canis can, however, all interbreed to produce fertile offspring, with two exceptions: the side-striped jackal and black-backed jackal. Although these two theoretically could interbreed with each other to produce fertile offspring, it appears they cannot hybridize successfully with the rest of the genus Canis.
So, no. They're too genetically different. | [
"Occasionally claims are made that interbreeding of dingoes and domestic dogs together with successful rearing of hybrids is a rare phenomenon in the wild due to supposedly radical differences in behaviour and biology and the harshness of the wilderness. However, cases of dogs that came from human households but no... |
Would it be possible to create a sunscreen-like substance for radiation of other kinds? Specifically, radiation caused by a nuclear explosion/accident? | The reason that sunscreen works is that the material absorbs the UV radiation instead of your skin and emits it as a less harmful wavelength.
Higher energy photons like X-rays are more and more difficult to block. In dentist offices they use lead vests because lead is a very dense material and therefore the photons encounter resistance when they try to pass through it. So I wouldn't exactly call them less harmful, but gamma radiation, the kind given off by a nuke, is even more energetic than that.
Water, concrete, and lead, are the most efficient blockers of this kind of radiation and unfortunately cannot be applied in sufficient amounts on your skin. So there is no known thin material that can protect anyone from high energy radiation.
Microwaves are actually low energy emissions below visible light. They are non-ionizing radiation and are incapable of hurting humans significantly in amounts found in a lifetime, contrary to some pseudo scientific beliefs. | [
"Medical organizations recommend that patients protect themselves from UV radiation by using sunscreen. Five sunscreen ingredients have been shown to protect mice against skin tumors. However, some sunscreen chemicals produce potentially harmful substances if they are illuminated while in contact with living cells.... |
how does the united states have such a high gdp per capita relative to other developed countries? | Well, not having their infrastructure and economies devastated by the carnage and destruction of two world wars happening right on their doorstep within 20 years of each other probably helped a little... | [
"In 180 years, the U.S. grew to a huge, integrated, industrialized economy that made up around one-fifth of the world economy. As a result, the U.S. GDP per capita converged on and eventually surpassed that of the UK, as well as other nations that it previously trailed economically. The economy maintained high wage... |
"Slowing light in Bose-Einstein Condensates" - What's actually going on here? | When light is in a medium, it's overall propagation rate changes. This is because, in simple terms, photons are absorbed and re-emitted as they pass through the medium. So even though every photon moves at c ( which it always will), the average speed that the 'total light' moves through the medium is less than c. This is true of any non-vacuum medium. | [
"In 1999, Danish physicist Lene Hau led a team from Harvard University which slowed a beam of light to about 17 meters per second using a superfluid. Hau and her associates have since made a group of condensate atoms recoil from a light pulse such that they recorded the light's phase and amplitude, recovered by a s... |
Which happens faster, erosion or uplift? | **TL;DR:** In the short term (lets say less than a million years, but that's a rough approximation) either erosion or uplift could be faster depending on the exact conditions in the area of interest, but we expect on the long term that landscapes approach a steady-state where erosion equals uplift.
**Longer Explanation:** Imagine a simple starting condition with completely flat topography with no uplift and no erosion. We then turn on uplift and we begin to build topography. Now, lets think about the rivers draining this landscape we're constructing (assuming that rivers are the primary erosional mechanism, which for most places other than high elevation areas where glaciers will dominate, is a good assumption). At any given point on the river, the erosional power of the river will be a combination of the slope and the amount of water draining through that point (which in a very simple sense is directly related to how much 'drainage area' is above that point) as these two properties will control the amount of work water can do on the bed of the river (or you could think about it in terms of transport of material, which ever works for you). This gives us a simple prediction that there should be trade off between these two quantities (i.e. at larger drainage areas / more water, the river requires less of a slope to do the same amount of work and the converse is true as well), which also explains the characteristic shape of river profiles. Congratulations, we've just derived the [stream power equation](_URL_0_), in words at least.
Okay, now that we have an idea of how rivers work, lets return to our previously flat, now uplifting landscape. As topography builds, two things are happening to the rivers, 1) they are trying to maintain connectivity to their base-level (e.g. sea level) and 2) if their discharge is not changing at any given point, they need to steepen to try to keep up with the uplift they are experiencing. Basically, the rivers will continue to steepen until they don't need to anymore. When does that happen? When the erosion rate equals the uplift rate. Once that condition has been reached, (and nothing changes) there is no mechanism by which the stream will erode at a rate faster than the uplift rate.
Now, to the first part of my simple answer that hints that at times erosion or uplift rates can be faster than the other. This stems from the assumption of no changing conditions. We generally know this to be false, i.e. a change in tectonics will cause changes in uplift rate, and changes in climate (e.g. rainfall) will change things like river discharge. So, if there is a change, what we expect to happen is that the rivers will readjust their shape (and thus the topography as whole will adjust) to reach a new steady-state where erosion again balances uplift rate. The amount of time this takes will depend on the type of change (i.e. a change in uplift rate or a change in climate) some of the details of the erosional processes at play, and the background 'erosional efficiency' (i.e. the K parameter in the stream power law) which is a mixture of climate and rock strength. In general, we expect response time to go with 1/K, which often translates to a few million years. If anyone is interested in a more technical discussion of response time, [this](_URL_1_) is the seminal paper on the topic. | [
"There are scientists who reject that uplift is the sole cause of climate change and are in favor of uplift as a result of climate change. Some geologists theorize that a cooler and stormier climate (such as glaciations and increased precipitation) can give a landscape a younger appearance such as incision of high ... |
Why are humans' (and other animals) white blood cells and antibodies so useless? | Most of these infections will be fixed by the immune system. As a matter of fact, most ear infections do not need antibiotics (source: _URL_0_).
As a matter of fact, our immune system's overzealous response is what causes a significant amount of damage. The inflammation caused by our immune cells usually is more harmful than the bacteria or virus.
The utility of our immune system is clearly demonstrated by people who have immune deficiency. | [
"Genetic studies of common diseases in humans suffer significant limitations for practical and ethical reasons. Human cell lines can be used to model disease but it is difficult to study processes at the tissue level, within an organ or across the entire body. Mice can be a good representation of diseases in humans... |
If we are attracted to good looking people, does that mean in the future there will no longer be any "ugly" people? | The cultural definition of "looks good" is very very subjective. Most striking example is how in the past in China, plump women were thought to be the most physically attractive, whereas today it is the opposite. Beauty is very subjective, and is not as one dimensional as people think. You can even find that example in current times: some people like "curvier" individuals, or "muscular" individuals, while others prefer "skinny" individuals.
Yes, there are certain qualities of the opposite sex that we are evolutionarily supposed to find attractive (large hips, symmetrical face, etc.) but they play second fiddle to the cultural atmosphere at the time. Basically the sum is more than the individual parts. You could also imagine a scenario where more diversity of certain physical attributes is better than a homogenized, "beautiful" population when it comes to that population's ability to respond to changes in the environment. | [
"BULLET::::- People tend to believe attractive people as smarter, more successful, more sociable, more dominant, sexually warmer, mentally healthier and higher in self-esteem than physically unattractive people.\n",
"Additionally, people who are of above average attractiveness are assumed to also be of above aver... |
From 2010 to 2016, student loan debt has approximately doubled, and the average student loan debt in 2016 has seen a 50% increase from 2010. What factors are driving this growth and what's the outlook of it's sustainability? | Increasing by nearly 50% is not doubling. According to your sources, the average debt in 2010 was $25,250. For that to double it would have to be $50,500, but it's only $37,172.
Converting to constant dollars using [this inflation calculator](_URL_0_), the 2010 debt would be $28,085 today, so that's a 32% increase, or about 1/3rd.
I don't know why that is, though. Maybe people are going to more expensive colleges. Let's look at one near me, University of North Texas.
[2010 tuition and fees](_URL_1_): $3,803.00 per semester for 15 hours
[2016 tuition and fees](_URL_2_): $5,244.80 per semester for 15 hours
That's a 38% raw increase, which is a 24% constant dollar increase, or about 1/4.
So tuition and fees both increased faster than inflation by about 25% for that one school. Still don't know why though.
According to [this article](_URL_3_) most of the disproportionate increase has been going to administration. | [
"A closely related issue is the increase in students borrowing to finance college education and the resulting in student loan debt. In the 1980s, federal student loans became the centerpiece of student aid received. From 2006 -2012, federal student loans more than doubled and outstanding student loan debt grew to $... |
what do these terms mean: p/e ratio, dividend, yield? | P/E ratio: Price to earning ratio. Price of the share vs what it is earning. Literally, Price / Earnings. If my company's shares are selling for $5, and it is earning them $0.25 per year, I have a P/E ratio of 5/.25 = 20. If your company's shares are selling for $10, but is also earning $0.25 per year, your company's P/E ratio is 10/.25 = 40.
Dividend: Let's say I have a lemonade stand. In order to get more money to buy lemons and sugar, I sell 10 shares of my company. If you own 1 share, that means you own 10% of my company. Let's say that I earn $100 more this year than last year, and I want to share it with you. I declare a dividend of $10 per share, and give you $10 (and $10 for every share. If you have 4 shares, you get $40)
| [
"Par yield (or par rate) denotes in finance, the coupon rate for which the price of a bond is equal to its nominal value (or par value). It is used in the design of fixed interest securities and in constructing interest rate swaps.\n",
"As the ratio of a stock (share price) to a flow (earnings per share), the P/E... |
what physical property of our brain allows us to think to ourselves? | Disclaimer: I am not a neuroscientist.
As far as I'm able to tell, this is not a question that neuroscience has been able to answer beyond simply, "you have a whole lot of neurons". Neurons are the cells in your brain which send and receive electronic impulses to other neurons. This firing and passing on of impulses forms intricate patterns, some of which seem to form something greater than the sum of its parts.
This is certainly not a scientific or rigorous explanation, but [the dialogue entitled *Ant Fugue*](_URL_0_) from [my favorite book](_URL_1_) presents a theory of how firings arise into consciousness by forming an analogy to an ant colony, each atomic part of which (that is to say, each ant) is completely oblivious to the grander structure to which it is a part, but where structure emerges through simple loops looping on top of each other, and loops of those looping on top of further loops of those. It's a pretty good ELI5 read (the dialogue, that is—the book is more ELI18-or-so?). | [
"Through most of history many philosophers found it inconceivable that cognition could be implemented by a physical substance such as brain tissue (that is neurons and synapses). Descartes, who thought extensively about mind-brain relationships, found it possible to explain reflexes and other simple behaviors in me... |
Could we ever build an optical/light microscope that could see atoms? | An optical microscope would never be able to see atoms. The wavelength of light is so much larger than the atoms that the amount of energy the atom displaces on the wavelength would be imperceptible, so the viewer couldn't see it. | [
"The idea of imaging with atoms instead of light is widely discussed in the literature since the past century. Atom optics using neutral atoms instead of light could provide resolution as good as the electron microscope and be completely non-destructive, because short wavelengths on the order of a nanometer can be ... |
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