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Which historical text, from any point in time, that we are aware of but not in possession of would be of greatest value to mankind if it were to be suddenly found? | The [Q document](_URL_0_) (a hypothesized early record of Jesus's teachings used as a source by the gospel writers) would be of enormous religious and cultural significance if an extant copy ever turned up.
Edit: This is a pretty interesting shot at a reconstruction of what Q might have looked like: [The *Logia*](_URL_1_). | [
"Widney said in \"Civilizations and Their Diseases\" (1937), I have never written for money. The sole object has been the carving out of broader lines for the human race. For more than fifty years of careful historical study, I have thought, and planned, and worked to this end. This ultimate purpose has run through... |
If acoustic energy is converted to heat when a material absorbs sound, is it possible for an audio source to produce enough acoustic energy to ignite something? | It IS possible, though as you said yourself highly
improbable. Sound is simply the vibration of particles in the air (hence why there's no sound in space) and that vibration hits and object and can vibrate it or induce heat, which is why you can break glass with a sound (not the only reason, mind you). If you played a sound at a certain frequency or amplitude (loudness) you could light something on fire, that said your speaker would light on fire long before due to the way they work (which is another question entirely). | [
"Absorbing sound spontaneously converts part of the sound energy to a very small amount of heat in the intervening object (the absorbing material), rather than sound being transmitted or reflected. There are several ways in which a material can absorb sound. The choice of sound absorbing material will be determined... |
What was the input of the Polish people in the second WW? How did they contribute. | Here's a brief answer:
Before the war Polish agents passed to the British an Enigma machine, which enables the British to be aware of how it worked even if its possession did not solve the problem of how to break German codes.
Polish units and individuals escaped to the West in 1940. Many pilots joined the French Air Force and then the Royal Air Force, proving highly effective and successful from the Battle of Britain (where a Polish squadron was the most successful) onward. There were also Polish squadrons in Bomber Command.
Polish research into paratroops was passed on to the British (who had done almost no work in the area) and things like the basic parachute harness were of Polish design. Polish paras were trained and used alongside British in 1944 at Arnhem. The British raised a Polish armoured division and other army units. This division fought with distinction on the shoulder of the Falaise pocket in 1944, holding despite desperate assault by fanatical SS troops trying to break out of the Allied encirclement. Many Poles fought in Italy.
The Soviet Union, despite massacring the 1939 Polish leadership at Katyn Forest, saw advantages in raising their own Polish units, which were officered by Russians given Polish identities. The Soviet commander Rokossovssky was Polish.
In 1944 Polish nationalists rebelled against their German overseers in Warsaw, as the Red Army approached. The Red Army halted on the Vistula River and the Germans had several weeks to put down the uprising in the most brutal fashion. Stalin also resisted Western, in particular British attempts to air drop supplies and weapons to the Poles.
It is also something of a myth that the Poles fought incompetently in 1939. They did not charge tanks with massed cavalry (in Polish terrain cavalry made some sense the Red Army used cavalry divisions there in 1944), and they would have cost the Germans quite dearly had not the Soviets surprise invasion of their rear forced them into surrender. Many German units suffered grievous casualties in Poland. | [
"It was the Polish contribution to the Allied war effort in the United Kingdom that led to the establishment of the postwar Polish community in Britain. During the Second World War, most of the Poles arrived as military or political émigrés as a result of the German and Soviet occupation of Poland. \n",
"During t... |
How strong is the link between benzodiazepines and dementia/Alzheimer's? What about marijuana? | Tried looking up a few studies for you. A retrospective study in France found that in those with dementia, there was a higher rate of exposure to psychotropic and anti-psychotic drugs, with anti-psychotic exposure having the highest association with dementia. Hypnotics/anxiolytics such as benzodiazepines carried a lower relative risk (1.74 risk ratio vs. 6.44 risk ratio for anti-psychotics). A prospective study from Washington that began in 2004 found no meaningful increased incidence of dementia in those exposed to benzodiazepines. It seems that the link between benzodiazepine use and dementia is not too compelling.
I wasn't able to find any reasonable articles that investigate a link between long-term cannabis use and dementia, although I'm sure this is being investigated. There are some papers out there about pilot projects investigating the use of medical cannabis oil to treat symptoms of dementia which have found promising results, but of course this does not prove any protective effects of cannabis with regards to dementia. But until cannabis is completely legalized, research in the area will be stifled.
Breining A, Bonnet-zamponi D, Zerah L, et al. Exposure to psychotropics in the French older population living with dementia: a nationwide population-based study. Int J Geriatr Psychiatry. 2016
Gray SL, Dublin S, Yu O, et al. Benzodiazepine use and risk of incident dementia or cognitive decline: prospective population based study. BMJ. 2016;352:i90. | [
"A number of studies have drawn an association between long-term benzodiazepine use and neuro-degenerative disease, particularly Alzheimer's disease. It has been determined that long-term use of benzodiazepines is associated with increased dementia risk, even after controlling for protopathic bias.\n",
"The long-... |
What would you see from inside the event horizon of a singularity? | RobotRollCall has the answers you seek.
_URL_0_ | [
"An observer crossing the event horizon of a non-rotating and uncharged (or Schwarzschild) black hole cannot avoid the central singularity, which lies in the future world line of everything within the horizon. Thus one cannot avoid spaghettification by the tidal forces of the central singularity.\n",
"As with the... |
what is the difference nutritionally between artificial and natural sugars, like why are the sugars from my apple any better for me than the sugars from my apple lollipop if it’s all still sugar? | Well there's not a chemical difference between the fructose in the apple and the fructose in the lollipop. There are two reasons the apple is better for you. 1. The apple has some vitamin C and probably others 2. The apple has dietary fiber and other complex carbs, which will lead to a smoother blood sugar curve than if you ate the same number of calories in lollipop form. | [
"Sugar-apple is high in energy, an excellent source of vitamin C and manganese, a good source of thiamine and vitamin B, and provides vitamin B, B B, B, iron, magnesium, phosphorus and potassium in fair quantities.\n",
"A sugar substitute is a food additive that provides a sweet taste like that of sugar while con... |
What is the smallest particle our skin can feel? | On the fingertip, you can sense the orthogonal displacement of your skin with a detection threshold of roughly 25 microns at 0.5 Hz (a 2 second smooth displacement). At 60 Hz for a half second that threshold is under 10 microns, and it drops to 1-2 microns at 250-300 Hz.
For movement parallel to the surface of the skin, stimuli a few orders of magnitude smaller (around 10 nm) can be detected simply because they drag the skin from side to side.
_URL_0_
Of course, based on this 1999 study published in the Journal of Neurophysiology, scientists created another study to demonstrate the same level of sensitivity and published their results in Nature. And the reviewers must have been very ignorant not to notice this. | [
"Another type, \"microscopic particles\" usually refers to particles of sizes ranging from atoms to molecules, such as carbon dioxide, nanoparticles, and colloidal particles. These particles are studied in chemistry, as well as atomic and molecular physics. The smallest of particles are the \"subatomic particles\",... |
why does long division work? | Lets do 123/5 with the same steps as in long division but in more rigorous fashion.
123 can be written as 1×100 + 2×10 + 3×1 (or with exponents as 1×10^2 + 2×10^1 + 3×10^(0). We'll need this later).
So now we have ( 1×100 + 2×10 + 3×1 ) / 5.
We can write this as
( 1×100 ) / 5 + ( 2×10 ) / 5 + ( 3×1 ) / 5
And further.
1/5 × 100 + 2/5 × 10 + 3/5 × 1
Now we can start doing the divisions.
1/5 would result in some fraction. We do not accept any fractions here. So lets go back few steps and combine the 100 term and 10 terms together.
( 1×100 + 2×10 + 3×1 ) / 5 = ( 12×10 + 3×1 ) / 5. = 12/5 × 10 + 3/5 × 1
12/5 is 2 and leftover 2/5 so. Lets keep the 2 here and move the leftover to the next term. So 12/5 ×10 = 2×10 + 2/5×10.
12/5 × 10 + 3/5 × 1 = 2×10 + 2/5 × 10 + 3/5 ×1 = 2×10 + 23/5 × 1
23/5 is 4 and 3/5 as leftover.
2×10 + 23/5 × 1 = 2×10 + 4×1 + 3/5 × 1
Again lets keep the 4 here and move 3/5 to the next term.
But we do not have any terms left? We can just add more.
At the beginnign we wrote the number using decreasing powers of 10 (10^(2), 10^(1), 10^(0)). So we can just add 0×10^-1 (=0×0.1) in there! (it is just zero, we can add zeros to number as many as we like)
2×10 + 4×1 + 3/5 × 1 + 0×10^-1 = 2×10 + 4×1 + 30/5 ×10^-1
30/5 is nice even 6.
So our result is
2×10 + 4×1 + 6 ×10^-1
Now we just turn this back into normal number.
24.6
Long division does these steps. (lets see how long division works with reddit formatting...)
5|123
-0 5 doesn't go into 1.
12 carry the 1 to the next term.
-10 5 goes into 12 2 times. 2×10 goes into the result so remove 2×5 from here.
23 And carry the remaining 2 to next term.
-20 5 goes into 23 4 times. 4×1 goes to the result so remove the 4×5 from here.
30 And carry the remaining 3 to the next term.
-30 5 goes into 30 6 times. 6×0.1 goes to the result so remove the 6×5 from here.
00 No more remainders to carry so we are done.
Result is 2×10 + 4×1 + 6×0.1 | [
"In arithmetic, long division is a standard division algorithm suitable for dividing multi-digit numbers that is simple enough to perform by hand. It breaks down a division problem into a series of easier steps.\n",
"In arithmetic, short division is a division algorithm which breaks down a division problem into a... |
What are the exact criteria with which historians can consider a past event to be a historical fact? | Let me start by proposing that history is not a mere pile of facts that we prove or disprove one by one and add to the pile. There are many things that may or may not have happened, but we can still learn lots from them.
A great example of this is in the book by Alfred Fabian Young, *The Shoemaker and the Tea Party: Memory and the American Revolution* (Boston, Mass.: Beacon Press, 1999). Young looks at the memories and tales told by George Robert Twelves Hewes about his role in the event that came to be known as "the Boston Tea Party." To pick one example of many in the book, Hewes claims that he worked shoulder to shoulder dumping tea overboard with the great Samuel Adams and John Hancock. While history seems to indicate that John Hancock was NOT actually involved in the physical dumping, it is unclear about where Adams was. Now, Young could have given up writing the book because he couldn't establish Hewes' memories as fact, but instead he uses the stories to illustrate how the rhetoric and ideology of the revolution infused Hewes' memory -- and to show what resonated with his eagerly listening audiences in the 1820s as he told his tales. Young reveals a story about the promise of egalitarian democracy and freedom from class bondages in Hewes' memories; and in that story, the question of the 'facts' of the Boston Tea Party is almost totally irrelevant.
> "Ideology did not set Georges Hewes apart from Samuel Adams or John Hancock. The difference lies in what the Revolution did to him as a person. His experiences transformed him, giving him a sense of citizenship and personal worth. Adams and Hancock began with both. [...] John Hancock and George Hewes breaking open the same chest at the Tea Partty remained for Hewes a symbol of a moment of equality."
I'll end by eloquently copy-pasting something I posted in another thread recently:
Basically, I think every historian comes to their own philosophy/epistemology/ontology of the past (how can we know what we know; what does exist and in what forms). However, there are certain broad movements in theory that basically set a standard for the field, upon which contemporary practitioners usually practice variations. (E.G. Post-modernism) If you are interested in reading scholars' various takes on the topic, two short and simple reads (if outdated!)that are good to start your journey with are:
* Marc Bloch, *The Historian’s Craft* (New York: Knopf, 1953)
* Edward Hallett Carr, *What Is History?* (New York: Knopf, 1962).
Heavier reads include:
* Peter Novick, *That Noble Dream: The “Objectivity Question” and the American Historical Profession* (Cambridge University Press, 1988).
* Gabrielle M. Spiegel, “The Task of the Historian,” *The American Historical Review* 114, no. 1 (2009): 1–15, doi:10.1086/ahr.114.1.1. | [
"A historical event can be defined as any occurrence from the past regardless of significance, with the term \"history\" an umbrella term relating to past events and any associated memories, discoveries, collections, organizations, presentations, and/or interpretations of them. This differs from a historic event wh... |
why does the healed skin on my wounds have the same patterns, wrinkles and creases as before? | Look at your hand, now move the inside of the base of your thumb towards your pinky. See all the folds and such? Your skin will fold the same way even after scarring.
Another example is that I game about as often as someone with a fulltime job is at work (30ish hours a week) my hand positioning presses the pinky side of my palm into my desk, causing a unique fold that wasn't there just a few years ago. If I sliced that part of my hand up (or burned it) the healed skin wont have those creases and wrinkles, but will develop them again as I continue to hold that unique hand position.
| [
"Fascia becomes important clinically when it loses stiffness, becomes too stiff or has decreased shearing ability. When inflammatory fasciitis or trauma causes fibrosis and adhesions, fascial tissue fails to differentiate the adjacent structures effectively. This can happen after surgery where the fascia has been i... |
Are hydrogen and oxygen molecules constantly forming new liquid water, or has all the water that can exist on earth already been formed? | Water is continually being created and destroyed by a number of natural processes. Probably the two fastest are the HOx cycle in the atmosphere:
O3 + photon ( < 300 nm wavelength) = > O2 + O(1D)
O(1D) + H2O = > 2OH
OH + organic compd. = > H2O + products
and photosynthesis:
xCO2 + xH2O = > (CHO)x + xO2
an example of this is where x is 5 or 6, and (CHO)x denotes a carbohydrate | [
"\"Stephan Riess of California formulated a theory that \"new water\" which never existed before, is constantly being formed within the earth by the combination of elemental hydrogen and oxygen and that this water finds its way to the surface, and can be located and tapped, to constitute a steady and unfailing new ... |
If the moon is spinning, why do we always see the same face? | It's called tidal locking. Gravitational force depends on the square of the distance. For objects that are close enough and big enough to us, there is a significant variance in the gravitational force on one side versus the gravitational force on the other side. The side of the moon facing us isn't heavier, but because it's closer, our gravity is stronger on that side. | [
"The Moon is in synchronous rotation as it orbits Earth; it rotates about its axis in about the same time it takes to orbit Earth. This results in it always keeping nearly the same face turned towards Earth. However, because of the effect of libration, about 59% of the Moon's surface can actually be seen from Earth... |
How would soft drinks (Carbonated) behave in space? | I remember a post on Reddit a while back about how both Coke and Pepsi had delivered soda to the ISS. Both times it ended in disaster because there isn't gravity to get the CO2 bubbles to rise up into a burp. Instead the gas stays in your stomach, accumulating, until you vomit it up. Along with a bunch of other liquid and solids. 🤮 | [
"Carbonated drinks have been tried in space, but are not favored due to changes in belching caused by microgravity; without gravity to separate the liquid and gas in the stomach, burping results in a kind of vomiting called \"wet burping\". Coca-Cola and Pepsi were first carried on STS-51-F in 1985. Coca-Cola has f... |
why is it ok to pray to statues and pictures of jesus if there’s a commandment against graven images? | The commandment is to have no other God's not no pictures, in Catholicism. Islam forbids images because they worry about exactly what has happened in the Catholic Church before where the symbols and pictures became more....up front important for lack of a better way of putting it. Can't say it's a bad idea, just think it's a bit of a harsh punishment. | [
"Latter-day Saints do not generally approve of or own crucifixes, and do not typically have statues in their local ward meeting houses, though some have been erected in LDS Visitor Centers and elsewhere. Portraits of Jesus, together with photographs or paintings of current and/or past church leaders, are allowed in... |
How are scientists getting estimates of 40-80% of populations that will contract the Coronavirus? | Herd immunity is the upper bound.
For measles, polio, and other prolific viruses its around 80%. This is what people with suppressed immune systems (who cant recieved vaccinations) depend on to prevent getting those viruses.
Here's an article: _URL_0_
Basically, it's the worst case scenario. 100% of the population wont get infected because eventually the amount of uninfected people are vastly outnumbered by those who have recovered already (and are thus immune due to developed antibodies). You cant infect somebody who was already infected.
If it gets bad enough that we rely on herd immunity, it's bad news. Hopefully social distancing is more effective.
I work for a catastrophe modeler, and unfortunately if we hit herd immunity, we are looking at over 2 million deaths in the US alone. | [
"Consequently, the TMRCA estimated from a relatively small sample of viral genetic sequences is an asymptotically unbiased estimate for the time that the viral population was founded in the host population.\n",
"Coronaviruses have single-stranded, positive-sense RNA genomes of 26-30 kilobases, by far the largest ... |
If the universe is constantly expanding, how will it ever be possible to have the same temperature at every single point in space? | First, there are two relevant laws of thermodynamics for your question:
The zeroth law of thermodynamics says that if object A is in thermal equilibrium with object B, and B is in thermal equilibrium object C, then A is in thermal equilibrium with C.
The second law of thermodynamics says that the entropy of an isolated system (such as the universe) can only increase over time. In the context of your question, this means that an isolated system will approach homogeneous thermal equilibrium.
You're on the right track with your thinking. The expansion of the Universe prevents thermal contact of distant regions of space. However, we know that the Universe was pretty darn small for a significant period of its early life, at least enough for thermal contact between opposite ends of the Universe to occur for some time. This works because one point of space comes to equilibrium with an adjacent point, and so on, so that a long chain of thermally equilibrated points can stretch from end to end of the Universe, thus by the zeroth law, the two ends approach equilibrium.
Several experiments (COBE, WMAP, and recently Planck are the missions that come to mind) have been sent into space to observe the [cosmic microwave background radiation](_URL_0_), which is basically a measure of the average temperature of the universe at any given point in space. It is because of the CMB that we can say that the average temperature of the Universe is ~2.7 K. So by determining just how uniform the CMB is, we can get an idea of how quickly it expanded in the first seconds after the Big Bang (i.e., how much time opposite ends of the Universe had to be in equilibrium).
At first glance, the CMB seemed perfectly uniform. We had to send up better and better experiments to see just how perfect its uniformity was. Eventually, we did notice that the CMB is slightly anistropic with 1 part in 100,000. So the Universe is not even now in thermal equilibrium as a whole, and this has been the case since the inflationary period after the Big Bang.
However, the Universe is also always increasing in entropy due to the second law. So regions of the Universe that are not in thermal contact will still run out of usable energy and regress to the temperature of the CMB in that local area. And, since the Universe will (presumably) continue to expand, the temperature of the CMB will asymptotically approach 0 K, and the Universe will be in thermal equilibrium (which gives the maximum entropy of a system). This concept of the Universe's fate is known as the [heat death of the Universe](_URL_1_). | [
"If the topology of the universe is open or flat, or if dark energy is a positive cosmological constant (both of which are consistent with current data), the universe will continue expanding forever, and a heat death is expected to occur, with the universe cooling to approach equilibrium at a very low temperature a... |
Are there any instances of modern wars being won from a production disadvantage? | The Spanish Civil War was an interesting case of the initially (industrially) inferior side eventually winning the war. Although Spain was rather undeveloped compared to the rest of western Europe, it did have some industry.
When the war did break out, the Republic managed to maintain control over the most important industrial regions - Barcelona and Madrid, as well as the mines in the north - controlling 60% of the country with 70% of its tax base as well as most vital supplies that were in the country at the time. However only 30% of Spain's agriculture fell into Republican hands at the outbreak of the war. Luckily much of this agriculture was in citrus and other cash crops, which the Republic could sell overseas for its much needed foreign cash and supplies. Even in mid 1937 after losing a large chunk of its initial ground to Franco, the Republic was concluded to be self sufficient still.
Unluckily for the Republic, though, they were plagued with disorganisation and internal revolution. With various parties fighting each other almost as much as Franco (especially the infamous May Days of 1937 in Barcelona), the Republic had to contend with little central control of the economy, as well as the large CNT collectivising industries and farms across the country (concentrated around Catalonia and Aragón) by its own accord and with variable success. With the rest of Republican government administration, the tax structure in the country crumbled with the breakdown of law and order in the initial outbreak, hindering their tax income efforts for at least the first year.
On the other hand, Franco managed to impose a fairly central and authoritarian economy, which had the benefit of foreign backing to keep it stable for the duration of the war, as well as the brutal methods the authorities used to keep the working population under control.
Another boost to the Francoists was their immense amount of foreign aid compared to the Republic. Almost as soon as the war started, Franco sought aid from Nazi Germany and Fascist Italy, which they both obliged with, particularly Italy which sent over 75,000 troops to aid the war effort over the 3 years of war. Franco received over $700 million (1940 USD) in aid completely on credit, compared to the Republican's $70 million from the Soviet Union. Furthermore, the Republicans had to sell their gold stocks to fund the rest of the aid from the USSR, which was the only nation willing to aid them due to the lack of willingness to intervene from France, America and Britain.
Francoist Spain managed to win the war despite their initial lack of potential in a war of attrition. Theoretically, the Republic should've won if one was to look at industry and manpower, but they didn't. It eventually came down to foreign support and internal stability, which Franco achieved much better.
Sources:
Seidman, Michael. *The Victorious Counterrevolution*
Preston, Paul. *The Spanish Civil War: Reaction, Revolution and Revenge*
Martín-Acena, Pablo; Martínez-Ruiz, Elena; Pons, María. *War and Economics: Spanish Civil War Finances Revisited* | [
"Wars between capitalist states are, as a rule, the outcome of their competition on the world market, for each state seeks not only to secure its existing markets, but also to conquer new ones. In this, the subjugation of foreign peoples and countries plays a prominent role. These wars result furthermore from the i... |
what's the difference between a terrorist, a rebel and a separatist? | A terrorist is someone who intentionally does acts of violence in order to instill fear or 'terror' in people to affect change or to carry out an ideology or idea.
A rebel is someone who is a part of or builds a group of people trying to overthrow an existing government or president.
A separatist is someone who usually wants to stay separate from a large group of people, or a government. ie.: The confederate states could be classified as separatist.
Someone can be a terrorist and not a rebel (Osama bin Laden). Someone can be a rebel and not a terrorist (Che Guevara, Founding Fathers of the US). Someone can be a Separatist and not a rebel (Jim Crow, Confederate Army).
Edit: A separatist *could turn into* a rebel, and a rebel could turn into a separatist. It depends on the context or the political climate of whatever country these groups are working in. | [
"The \"Nacionales\" or Nationalists, also called \"insurgents\", \"rebels\" or, by opponents, \"Franquistas\" or \"fascists\" —feared national fragmentation and opposed the separatist movements. They were chiefly defined by their anti-communism, which galvanised diverse or opposed movements like Falangists and mona... |
Whatever happened to the Magi? | They are known by different names now. 'Magi' during the classical Greek period came to mean generally anyone skilled at astrology and so it was not specific to Zoroastrianism or a priesthood (think of the three wise men i.e 'magi' of the bible - the word there just means 'wise king' (wise because they knew to follow the star) there's also the linguistic impact of most of the community having moved out of Iran and in to India and further afield.... here's how the priests are now known:
Dastur - high priest
Mobed/Mobad - general word for 'priest' derived from middle-Persian used as an honorific for all ranks and specifically for a certain rank able to do ceremonies etc.
Herbad - lowest ranking priest
NB - Most Zoroastrians now live in South Asia and are know as Irani and Parsi
There are quite a few differences between the various populations in terms of calenders, festival dates, ritual and terminology The names I've given refer to Parsi priests but they could well differ with other communities. | [
"The magi were a group of on-site Zoroastrian observers, located in their separate but attached structure possibly a caravanserai, paid and cared for by the Achaemenid state (by some accounts they received a salary of daily bread and flour, and one sheep payment a day). The magi were placed in charge of maintenance... |
why does the internet hate skrillex so, so much? | I can't speak for the internet, but I can provide a logical explanation. I think we can both agree that not many people like dubstep. Skrillex is the face of neo-dubstep. When people despise something, they look at its most popular representation and hate him/her.
Basically, skrillex represents dubstep, people hate dubstep, therefore they hate Skrillex. | [
"In a positive review for \"MSN Music\", Robert Christgau called \"Bangarang\" an \"electronical vista\" and said it is \"a pop record because its shamelessly hedonistic barrage of proven dancefloor tricks will obviously be more fun at home than in a club.\" August Brown of the \"Los Angeles Times\" felt that, alth... |
Why don't waves through water travel at the speed of sound in water? | Waves like sound transport potential and kinetic energy through vibration and excitation. There is no mass transit.
Water waves transport these energy forms as well but also exchange mass, causing impulse exchange and therefore viscosity effects to enter the picture. | [
"The influence of sonic waves traveling through liquids was first reported by Robert Williams Wood (1868–1955) and Alfred Lee Loomis (1887–1975) in 1927. The experiment was about the frequency of the energy that it took for sonic waves to \"penetrate\" the barrier of water. He came to the conclusion that sound does... |
How accurate is the show The Tudors? | I just finished watching it recently, so I looked into it. However, as I'm not expert on Tudor England, I'm just going to talk about a few specific things that I'm confident of.
The first, is the order of events and specifically their time. Sometimes the show changes the order of unrelated events slightly.
The show starts shortly before Henry's divorce of Catherine. It shows him as a young, vital, popular King. And certainly, this is how Henry was when he was young, and it's understandable of the show to want to show this, as most people just think of him as a fat middle-aged man. However, by the time of his marriage to Anne Boleyn, he was already 41. Henry was married to Catherine of Aragon for 24 years, but from their divorce to his marriage to Catherine Howard, it was only 11 years, in which he went through Anne Boleyn, Jane Seymour, Anne of Cleves and Catherine Parr.
So the show seems to be going through most of his life, from a young man to his death, but really, the first 3.5 seasons only cover about 12 or 13 years, with a few events from earlier put in.
Another thing they changed is some of the minor characters. Several characters are conflated, or swap roles, or don't fit their real personalities.
For example, Mary's sisters. In the show, Henry has one sister, Margaret, who marries the King of Portugal briefly, then secretly marries the upjumped commoner, the Duke of Suffolk. He later becomes Henry's longest serving councilor.
However, notice that in the last series, Henry several times complains about his nephew, the King of Scotland?
In real life, Henry had two sisters.
Margaret married the King of Scotland, and its her son James V that Henry is referring to. Her great-grandson of course, was to become James VI/I of Scotland and England (as Henry VII had considered in case his son's lineage died out, incidentally).
The other sister Mary, meanwhile, married the aged King of France (the father of the one in the show, who is shown to rule France for most of Henry's reign in the show, but actually didn't), not Portugal. Once he died of old age, she indeed secretly married the Duke of Suffolk as in the show, and Henry banished them temporarily from court.
However, the real Charles Brandon, Duke of Suffolk, came from a wealthy noble family that had supported Henry VII and lost his father fighting Richard III (which is why he was raised with Henry VIII, and became one of his closest friends), and didn't do many of the things he's shown to do later in the show. He was indeed one of Henry's main advisors, and often led military campaigns, but some of the things he did in the show were actually things done by the Duke of Norfolk. That's the uncle of Anne Boleyn (and also Catherine Howard, not something shown in the show, where another guy turns up to be her uncle), who in fact survived the fall of his niece, and continued to be very powerful until late in Henry's reign, when he lost favour and was thrown in prison.
So, there are lots of small details that they changed. And of course, they don't show Henry as the obese man he was in old age, especially after his leg injury.
Overall, however, I felt that while it's not up to the standards of historical accuracy that would be expected for an academic work, I don't think it's terrible. It does show reasonably, I think, the feel of the court, and of Henry's personality: how he started off as a fairly popular king, educated in the humanist way, but became more tyrannical and arbitrary over time. Also, the way the courtiers manipulate him. Finally, one thing I was pleased with is that I think, unusually for a popular history show, is that they show the central importance of religion, and how importantly people took it. For many characters in the show, religion is not just a political faction or something opportunistic, but also something they passionately, genuinely believe in. And yet, at the same time, they resist showing them as simply blind fanatics, as TV shows have a want to do with pre-modern religion. For example, Cromwell is corrupt, at times cruel, willing to compromise to keep the King's favour, but at the same time he is shown as genuinely believing in Protestantism (or, as they generally called it, Reform). Henry VIII resists going too Protestant because, as much as he wants a divorce, he genuinely believes in much of Catholic doctrine, and is suspicious of the reformers' goals. This does appear to be what Henry thought in real life.
Overall... it's not perfect by any means, but it's much better than Reign. | [
"The Tudors is a historical fiction television series set primarily in 16th-century England, created and written by Michael Hirst and produced for the American. premium cable television channel Showtime. The series was a collaboration among American, British, and Canadian producers, and was filmed mostly in Ireland... |
How can we hope to detect faint intelligent signals from exoplanets when we aren't even able to detect the light from those planets? | Well... the problem with seeing an exoplanet is that the star is so bright you can't get a long enough exposure to see the planet's light. (like trying to see a speck of dust near a spotlight) There are some neat strategies to work around this, like a giant shadow-casting shield that you'd space in front of your telescope to block the star's light, but allow the planet to be visible.
But yes too.. it's seemingly unlikely that *random* broadcasts would be visible outside of their neighborhood (maybe a light year or two), with signal being lost to noise. But maybe if you were to focus a beam, you'd have less energy loss over distance, and extend your range. But now you have to point at a target in addition to having a high power source.
So if we detect external signals it will almost certainly be a deliberate attempt to send an interstellar message in our direction. | [
"In 2018, astronomers noted, \"Detecting SIMP J01365663+0933473 with the VLA through its auroral radio emission, also means that we may have a new way of detecting exoplanets, including the elusive rogue ones not orbiting a parent star ... This particular object is exciting because studying its magnetic dynamo mech... |
When you ingest salt NaCl what does the body do with the chlorine after the sodium is absorbed? | [NIH Glossary - Chloride](_URL_0_) | [
"Sodium chlorite is derived indirectly from sodium chlorate, NaClO. First, sodium chlorate is reduced to chlorine dioxide, typically in a strong acid solution using reducing agents such as sodium sulfite, sulfur dioxide, or hydrochloric acid. This intermediate is then absorbed into a solution of aqueous sodium hydr... |
Can any given 2D shape be expressed as a single (probably incredibly complex) equation, or do many shapes require a piecewise graph? | Yes. I used to waste so much time in high school typing long formulas into my TI-83 to get it to graph shapes I drew out ahead of time on graph paper. With enough time on your hands, you can use its parametric grapher to graph out your signature.
I used the [Nyquist-Shannon sampling formula](_URL_0_). It smoothly interpolates between sampled points using sine curves. (Meaning, the sine function is used in the sampling; the points them selves are not joined with sections of sine curves the way you might be thinking of them.) If you draw a kooky shape, and record the coordinates of lots of points on the shape very precisely, you can use N-S sampling to reconstruct the shape using a very long sum of sines. The number of terms is equal to the number of sampled points. | [
"Geometric shapes are often represented as 2D curved surfaces, 2D surface meshes (usually triangle meshes) or 3D solid objects (e.g. using voxels or tetrahedra meshes). The Helmholtz equation can be solved for all these cases. If a boundary exists, e.g. a square, or the volume of any 3D geometric shape, boundary co... |
How did the sections of US states become known as "counties" even though they have never been ruled by counts? | Point of order: The British counties have never been ruled by counts (or viscounts): it stems from the Normans, who simply took over the Saxon shires (that's why it's all "Hampshire", "Cheshire", "Renfrewshire" etc.), but brought their Norman French with them (counts actually being a thing on the continent).
Historically, British counties started out as either kingdoms in their own right ~~after~~ from before Alfred the Great, or just happened to be the administrative division used for taxes (and sheriffs and things).
^(edit: spelling; edit 2 19:23 UTC: slip of tongue) | [
"Counties in U.S. states are administrative divisions of the state in which their boundaries are drawn; for example the territorially medium-sized state of Pennsylvania has 67 counties delineated in geographically convenient ways. By way of contrast, Massachusetts, with far less territory, has massively sized count... |
Modern day concrete still doesn’t compare to the concrete made by the Romans. How was the recipe lost? | I don't mean to discourage further discussion, but this topic emerges quite often. You might want to read the response by /u/TectonicWafer in [this discussion](_URL_0_). For some additional insight, you may also read the short discussion about 'losing knowledge' [here](_URL_1_). | [
"Roman concrete, also called opus caementicium, was a material used in construction during the late Roman Republic until the fading of the Roman Empire. Roman concrete was based on a hydraulic-setting cement. Recently, it has been found that it materially differs in several ways from modern concrete which is based ... |
the difference between a particulate, gas, and vapor | * Particulate - small solid particles dispersed into the are
* Vapor - individual molecules mixed in with the air, but not at high enough of a temperature to be a gas...sometimes incorrectly used as a synonym for gas
* Gas - molecules travelling at high enough speed they cannot for the temporary and permanent bonds that characters liquids and solids | [
"In physics, a vapor (American English) or vapour (British English; see spelling differences) is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is di... |
Do male and female human genitalia exhibit a similar degree of variation in length and width? | There definitely is substantial variation in the size of the female reproductive tract, but I am not aware of any studies that actually try to compare the variability to that for penises.
It would be a challenging study because the vagina both opens up and lengthens quite substantially during arousal and at different times in a woman's cycle, and it would be hard to keep everything consistent when taking measurements. It would be like trying to do a study on average penis size, but all you get is a bunch of penis measurements but it's random and unknown whether the measurement was taken while erect of flaccid. You would have to measure the same woman several times in several different states. | [
"There is significant sexual dimorphism in the genus. Males measure in length, while females are slightly longer at . The subgenital plate is longer in the male than in the female. Females are easily distinguished from males by the presence of a large, sword-shaped ovipositor which measures nearly half the length o... |
is the united states currently at war? | We are at war in virtually any meaningful sense, we have just refused to call it such because that word has real legal and political ramifications. | [
"The US has been on the ground and directly involved in the 17-year old war that analysts have described as stalemate. Ending the 17-year conflict has eluded former US presidents and Donald Trump has said that he considers the war too costly.\n",
"The war marked American entry into world affairs. Since then, the ... |
Do 2 atoms of the same element (I.e hydrogen) always weigh the same? Why or why not? | No, two atoms of the same element will not always have the same mass. Two atoms of the same element can have a different number of neutrons in their nuclei. Since neutrons have a significant mass compared to electrons, this can lead to an important difference in mass between the various isotopes of an element. This fact is very important to isotope enrichment, such as is needed to develop nuclear bombs.
Additionally, atoms can be in different ionization states, meaning that they are missing electrons or have extra electrons. Since electrons carry mass, an atom that is missing an electron will have less mass then an otherwise identical atom in the neutral state.
Even if two atoms are the same element, the same isotope, and in same ionization state (they have the same numbers of electrons, protons, and neutrons), they can still have slightly different masses. Due to E = mc^2 , when energy is pumped into an otherwise closed system, the system as a whole gains mass. Therefore, two atoms of the same element, isotope, and ionization state can be in different excitation states and therefore have slightly different masses. All of the pieces of an atom (electrons, neutrons, and protons) can be excited to higher energy levels within the atom. | [
"Equivalent weights were not without problems of their own. For a start, the scale based on hydrogen was not particularly practical, as most elements do not react directly with hydrogen to form simple compounds. However, one gram of hydrogen reacts with 8 grams of oxygen to give water or with 35.5 grams of chlorine... |
Did the Nazis view blonde-haired and blue-eyed Slavs and Jews as any better than the others? | The blond-hairs / blue eyes thing is actually a gross simplification of the racial policies of Nazi Germany. They were mainly obsessed with blood purity and Japanese were seen as vastly superior to the slavs despite not having blond hairs.
A good example of this obsession for blood purity was Reinard Heydrich, a high ranking Nazi who, despite being the archetypical pure aryan in appearance (blond, ruthless and a fanatical nazi), has been the target of a smear campaign where rivals launched rumors according to which he had a Jewish ancestor, meaning he was not pure aryan.
It was a very grave accusation for a Nazi official and the Reich paid a "racial expert" to investigate closely Heydrich's genealogy to make sure the rumors were unfounded. His report showed that Heydrich had no "Jewish taint" in his blood. If the report got positive Heydrich would probably have been in trouble and could have been expelled from Nazi party.
All that to show you that it was not really about hairs or eye color but about purity and ancestry. Slavic people had a unpure blood for the Nazis and so did the jews, meaning that if you had the taint you were good for the concentration camp, whatever your eye or hair colors were.
Concerning the accusations of being unpure toward Heydrich, you can read more about these in *"Hitler's hangman: The life of Heydrich"* by Robert Gewarth. | [
"In his early writings Ploetz credited Jews as the second highest cultural race after Europeans. He identified no substantial difference in \"racial character\" between Aryans and Jews, arguing that the mental abilities of Jews and their role in the development of human culture made them indispensable to the \"proc... |
what are the benefits of methadone/a methadone clinic? | It's an opiate like heroin so users wont withdraw and it's little less extreme. You can think of it like shorts with cigarettes, good for tapering off if you're trying to quit. | [
"While methadone clinics are generally considered to be effective treatment options for patients addicted to opioids, especially when other interventions have failed, there is controversy surrounding the placement of methadone clinics. There is a perception that the presence of the clinics attracts crime to surroun... |
How did RBMK reactors come to be and how were they different from other models used in the western world? | Briefly, the RMBK was a very unusual reactor design, optimized for the demands of the Soviet bureaucracy and production needs. The basic requirements that the RMBK was trying to satisfy were:
* the design had to be a relatively cheap way of producing gobs of electrical energy
* the reactor was designed to be capable of being designed and manufactured locally, as opposed to in a centralized facility (this is related to the cheapness and the labor model)
* the military (who essentially ran the reactor development program) wanted it to be capable of also producing plutonium for military purposes (no RMBKs actually did this, but they wanted the option)
The result was a reactor that looks very different from most Western reactors and looks even different from the other main Soviet design, the VVER, which is basically the Soviet equivalent of the Pressurized Water Reactor (PWR). The PWR/VVER both require very specially produced reactor vessels, and both use expensive containment domes, and both are essentially difficult to use for the production of military plutonium (you can't circulate fuel through them very quickly). The RMBK by comparison does not have a special reactor vessel, lacked a containment dome, and could circulate fuel very quickly. Importantly they could use the existing Soviet industrial workforce very efficiently, without the need to construct new facilities or train workers for radically new skills — this was a high priority in the late 1970s USSR, when the design was approved.
The RBMK had significant safety problems which are obvious in retrospect, though it is of note that with careful operation, the accident rate can still be very low (there have been RMBKs operating continuously since Chernobyl without incident). Similarly one can run VVER/PWRs in ways that produce accidents (Three Mile Island was PWR accident), and the other major design in operation, the Boiling Water Reactor, has its own flaws as well (Fukushima was a BWR accident). Obviously the lack of a containment dome is dangerous no matter what — this was also an artifact of the Soviet bureaucracy and engineering culture, in which to admit the possibility of engineering fault was seen as attacking the Soviet state.
I think it is worth noting that _every_ reactor design has the hallmarks of its original priorities and goals written upon it. The RMBK is not unique in this respect, though the specific priorities and goals are very attuned to the place and period it was created, and, regrettably, said priorities and goals were less focused on safety than they ought to have been, with grave consequences.
As I always emphasize, you can design a reactor for whatever priorities you want (safety, economy, plutonium production, whatever), but some of these priorities can interfere with one another (e.g., if you optimize for economy you can cut into safety, and vice versa). So it is important that you know what your priorities are, and what priorities your production and regulatory systems are set up to honor. In the case of the RBMK, it is clear that safety and transparency were far too under-valued, both in the reactor design, but also in its operation.
If you would like a lot more detail into the development of the RBMK and VVER, Sonja D. Schmid's _Producing Power: The Pre-Chernobyl History of the Soviet Nuclear Industry_ (MIT Press, 2015) is the best technical history of Soviet reactor development prior to Chernobyl, and goes into great detail into how the institutional divisions (between, say, the military and civilian aspects of nuclear power in the USSR) and priorities shaped these technologies. | [
"The RBMK is an early Generation II reactor and the oldest commercial reactor design still in wide operation. Certain aspects of the RBMK reactor design, such as the active removal of decay heat, the positive void coefficient properties, the graphite displacer ends of the control rods and instability at low power l... |
How long does it take for a particle to loop around LHC? How much does it change for the particle due to time dilation? | _URL_0_
> When running at full design power of 7 TeV per beam, once or twice a day, as the protons are accelerated from 450 GeV to 7 TeV, the field of the superconducting dipole magnets will be increased from 0.54 to 8.3 teslas (T). The protons will each have an energy of 7 TeV, giving a total collision energy of 14 TeV. At this energy the protons have a Lorentz factor of about 7,500 and move at about 0.999999991 c, or about 3 metres per second slower than the speed of light (c). It will take less than 90 microseconds (μs) for a proton to travel once around the main ring – a speed of about 11,000 revolutions per second.
So, if the protons going around the LHC each had watches, their watches would appear to elapse by (9 x 10^-5 s) / (7500) = .012 microseconds, from a stationary observer's point of view. Of course, in the protons' reference frame, time would appear to pass normally, but the the watch on the stationary observer would appear to move very quickly.
Edit: Yes, I should have divided to get the indicated time on the proton as observed from a stationary position. From that point of view, it would appear that the protons' watches were moving very slowly (and I confused myself into thinking that time moving slowly corresponded to a larger delta on the proton watch - not the case, as is clearly indicated in comments below). | [
"Today, time dilation of particles is routinely confirmed in particle accelerators alongside with tests of relativistic energy and momentum, and its consideration is obligatory in the analysis of particle experiments at relativistic velocities.\n",
"Time dilation as predicted by special relativity is often verifi... |
if sea level has been rising then how come it is not evident from the beach yet? | The sea has risen by about 15cm due to the 0.8^o C rise in global temperatures so far; this is not enough to notice on a typical beach without careful measurement.
Some places, such as Tuvalu and Bangladesh, have experienced more drastic and obvious effects due to the rise.
Scientists are concerned that the rise will increase much further in future partly due to positive feedback loops causing greater warming. These are due to things like a reduced albedo, released methane from ice sheets, and a positive feedback between temperature and CO2.
The rise in sea level is largely due to the melting of ice on land. The ice masses are mahoosive and take a long time to melt. Even without further warming the ice will continue to melt for several centuries so the sea will rise further in any case. | [
"In addition, rises in sea level thought to be due to global warming appear likely to make low-lying areas of land increasingly susceptible to flooding, while in some areas the coastline continues to erode at a geologically rapid rate.\n",
"In addition, rises in sea level thought to be due to global warming appea... |
Why do we feel comfortable in some positions and not others? | It has a certain degree to do with blood flow. This also explains why we roll around in bed at night- in some positions, blood may be restricted to some areas due to pressure on the blood vessels, so we roll to another position to redistribute the bloodflow.
How comfortable you are in a position whilst concious is likely to be more to do with how much pressure are on certain body parts or how strenuous that position is. | [
"BULLET::::- If two people of different social standings talk to each other, the person with a higher position usually takes a more relaxed attitude. Their posture may be unbalanced, relaxed, and may appear to be nonchalant. A person with a lower position often maintains symmetrical posture by placing both hands on... |
food stamp fraud | Vendors (grocery stores, etc) receive reimbursement from the government for accepting food stamps as payment for (approved) food items. Things that cannot be purchased with them include non-food items, hot pre-prepared foods, as well as cigarettes and alcohol.
What she was doing was allowing people to pay for non-eligible items with food stamps. This was beneficial for her because she would charge more and pocket the difference. So for a $10 case of beer she might charge $20 in food stamps and then keep the extra $10 for herself.
She would then submit to the gov for reimbursements and make up fake receipts for eligible things that people "bought" | [
"Department of Agriculture v. Moreno, 413 U.S. 528 (1973), was a United States Supreme Court case that declared a provision of the Food Stamp Act denying food stamps to households of \"unrelated persons\" to be a violation of the U.S. Constitution. The Court held that provision to be irrelevant to the stated purpos... |
why does your neck get tense when you’re stressed and how does a massage fix it? | When you are stressed, you experience fight-or-flight, even if the stressor is emotional/psychological in nature. When this response occurs, it causes you to produce more adrenaline. Adrenaline causes muscle tension (muscle tension being a sign of stress). If you massage a muscle, you can cause that muscle to relax. So stress increases adrenaline, causing muscle tension, massage relaxes muscles. | [
"Progressive muscle relaxation helps relax your muscles by tensing certain parts of the body (such as the neck), and then releasing the tension in order to feel the muscles relaxing. This technique helps for people with anxiety because they are always tense throughout the day.\n",
"A study by Thomas and Siever sh... |
Knowledge of coats of arms in medieval Europe | Yes, a noble was supposed to know the coat of arms of at least the important lords, at least in his own army (because it's rather easy to deduce who's an enemy when you know who's your friend).
The most notable example for this (or rather for it's absence, from which a presumed knowledge for nobles can be inferred) is the Battle of Worringen in 1288, the battle with the largest amount of knights in the middle ages.
The leader of the one side was Siegfried von Westerburg, Archbishop Elector of Cologne, who sported more armored riders than soldiers on foot, making infantry for him rather negligible mostly used to guard the baggage train. On his opponents side fought the people of Cologne, who wanted to weaken the position of the Archbishop to better their own position within the city politics (the Archbishop had a very strained relationship to the citizens of Cologne, with one of his predecessors having been evicted from the city by force at one point).
Most of these people of Cologne were fighting on foot and were not part of the patricians but regular citizens. Now, this militia of citizens had no formal training and very little "noble" education - and subsequently, when they entered the fray, they attacked everyone (or rather: all armored riders) indiscriminately, which is attributed to them not knowing friend from foe because they could not recognize the colors of the nobles.
Another factor for why knowing the colors of ones enemy was important was that battles in the Middle Ages were not really fought to the death. The goal was to take as many of the enemy knights as prisoners to ransom them to pay for the massive costs of waging a war. Knowing who is who is rather essential if you want to know who needs to be spared at almost all costs because a high ransom is to be expected.
So to summarize: Yes, a noble was supposed to know the colors of his friends at least and of his enemies to a large extent when he went to war.
Sadly I can't give you a source for it in English, but on the off chance that you can read German, this information is taken from:
*Lehnart, Ulrich: "Die Schlacht von Worringen 1288. Kriegführung im Mittelalter. Der Limburger Erbfolgekrieg unter besonderer Berücksichtigung der Schlacht von Worringen", Frankfurt 1993* | [
"The first evidence of medieval coats of arms is found in the Bayeux Tapestry from the 11th century, where some of the combatants carry shields painted with crosses. Coats of arms came into general use by feudal lords and knights in battle in the 12th century. By the 13th century arms had spread beyond their initia... |
Do any animals live at the extreme poles and how do they survive? | > A lone polar bear, tracks of an Arctic fox, unidentified sea creatures, and several birds have been observed at the North Pole over the years.
[Source](_URL_0_) - you still have the ocean as food source.
At the South Pole: Technically humans live there, and a few animals live on them. But outside the research station I didn't find any mention of animals living there. | [
"Because totem poles are created from an organic material they can be a place of habitat for many diverse species. They can become an ideal home for many insects such as wasps, bees, carpenter ants or termites. In addition, poles make great homes for birds as many nests have been found at the top of poles. Biologic... |
how do tolls work? do you really get in trouble for running one? | You mean on a road? A machine will take a photo of your license plate if you go through without paying. Some offer an option to pay the toll afterward, by Web or by mail. (Some don't have that option.) You may get a fine/ticket in the mail if you don't pay. | [
"To solve the problem, some toll officials now collect tolls by actually walking to cars in the line and collecting tolls and handing over receipts. This somewhat alleviates the problem, even though the core of the problem is still existent to this day.\n",
"Toll restriction or toll denial is a feature offered by... |
What are the best sources to understand Gaius Marius's reforms in Rome? | Sorry it took me a while, hope this is helpful. The bibliography from my old Marian Reforms paper follows. Especially useful were Gabba, Kildahl, Smith. If you want my full paper (with page numbers for references) let me know, I'll find a place to put up the pdf or you can PM me with an email address. Cheers.
Adcock, F. E. The Roman Art of War Under the Republic. New York: Barnes and Noble Books, 1995.
Cicero. De Republica. In The Political Works of Marcus Tullius Cicero: Comprising his Treatise on the Commonwealth; and his Treatise on the Laws Vol I. Translated by Francis Barham. London: Edmund Spettigue, 1841-42.
Dobson, M. The Army of the Roman Republic: The Second Century BC, Polybius and the Camps at Numantia, Spain. Oxford: Oxbow Books, 2008.
Gabba, E. Republican Rome, the Army, and the Allies. Berkeley: University of California Press, 1976.
Goldsworthy, A. The Roman Army at War 100 BC-AD 200. Oxford: Clarendon Press, 1996.
Kildahl, P. Caius Marius. New York: Twayne Publishers, 1968.
Livy. Ab Urbe Conditi Libri. Translated by F. G. Moore. Cambridge: Harvard University Press, 1949.
Plutarch. Gaius Marius. In Fall of the Roman Republic. Translated by Rex Warner. London: Penguin Books, 2005.
Plutarch. Tiberius Gracchus. In Makers of Rome. Translated by Ian Scott-Kilvert. London: Penguin Books, 1965.
Sallust. The Jugurthine War. Translated by John Selby Watson. New York and London: Harper & Brothers, 1899.
Scullard, H. From the Gracchi to Nero: a History of Rome 133 BC to AD 68. London: Routledge, 1982.
Seyffert, O. Dictionary of Classical Antiquities. Edited by H. Nettleship and J. E. Sandys, _URL_0_.
Smith, R. Service in the Post-Marian Army. Manchester: Manchester University Press, 1958. | [
"His research has focused mainly on Roman history of the Republican and early imperial periods, and in particular on three aspects, namely war, imperialism and international relations; Roman historiography; and the transition from Republic to monarchy under Augustus. These themes have been explored in his monograph... |
how did humans in asia evolve to have narrower eyes, why did africans skin stay black while arabic and european peoples became lighter? | If you live in the tropics, dark skin is a helpful adaptation, because it protects your skin from sunlight (fewer sun burns and cancers).
If you live in the northern latitudes where there is significantly less sun certain times of the year, light skin is a helpful adaptation, because it allows more sunlight to penetrate the dermis, thereby creating more vitamin D.
The primary characteristic of east Asian eyes is called the *epicanthic fold*, and we believe it may have evolved to protect the eye from harsh winds, but the jury is still out on that one. | [
"Convergent evolution in humans includes blue eye colour and light skin colour. When humans migrated out of Africa, they moved to more northern latitudes with less intense sunlight. It was beneficial to them to reduce their skin pigmentation. It appears certain that there was some lightening of skin colour \"before... |
Wehrmacht Clean Hands in the West? | As for Rommel specifically: more can be written on this, but you might want to read ["Rommel's legacy"](_URL_0_) by /u/commiespaceinvader.
EDIT: As for the source of the Wehrmacht Clean Hands myth, I suggest the reply to ["Did the Rommel Myth and Clean Wehrmacht myth (and others) pushed after World War II come from Government level or Academia?"](_URL_1_) also by commiespaceinvader, with a bibliography at the end. Replies by /u/kieslowskifan and /u/]Georgy_K_Zhukov list books for further reading.
EDIT 2: I *am* sorry for not looking further down in previous postings before writing this. A few examples of Wehrmacht war crimes in the west (scattered in more about the east) is in ["Just how much of the Wehrmacht was dirty?"](_URL_2_) , again by commiespaceinvader.
This is not to discourage discussion. Further questions, data, and debate are welcome.
| [
"The Wehrmacht: History, Myth, Reality is a 2002 book by German historian Wolfram Wette which dealt with the issue of Wehrmacht's criminality during World War II and the legend of its \"clean hands\". The original German-language book was translated into five languages; the English edition was published in 2006 by ... |
Could we just inject dopamine and other molecules that cause feelings of well-being into our bodies and stay happy for the rest of our lives? | There is no safe or effective happiness treatment. Short term happy pills (e.g. cocaine, which causes elevation in levels of dopamine right in the areas that cause you to feel happy) don't work for long.
> If we could, every other human activity would be pointless, as we only do such things to be happy( i.e. get dopamine rushing through our bodies), right?
I think that's partly right. Rats that learn to electrically stimulate their own mesolimbic dopamine pathway get such a great high that given the choice between food or sex and another hit of stimulation, they can willingly starve themselves to death for another hit. Some heroin users have said that heroin fills a void that makes them feel fulfilled and all the yearning that they ever had for love, accomplishment, etc. is all addressed wonderfully and nothing else is needed anymore (during the high). Soon thereafter, of course, more heroin is needed. | [
"On the positive side, enhanced emotional well-being is seen to contribute to upward spirals in increasing coping ability, self-esteem, performance and productivity at work, and even longevity. Thoughts determine our feelings, and thoughts are nothing more than firings of neurons. And those feelings that our though... |
*How* do left/right handed molecules form and how are they different? | Your left hand is structurally distinct from your right hand. In other words, there's no orientation, rotation or any translation that will turn your right hand into your left hand. What this means is there's absolutely no way to put your left hand in a right handed glove and vice-versa (have a go).
This chirality, as its termed, works in the exact same way for molecules. For example, 'left handed' molecules can't fit into 'right handed' enzymes. An enzyme would be right handed because it's made up of smaller right handed molecules.
I just to make sure that it's understood that not all objects can be left or right handed. Just because it has a mirror image it doesn't mean the mirror image is the other hand. For example, imagine you put a mirror next to a coffee cup and then removed the mirror but kept the reflection there as a real object. You could translate one of the cups into the other and they would perfectly match - they are the exact object. And that's the key. Left and right handed objects/ molecules are structurally distinct objects/ molecules. | [
"The right hand side is a sum over conjugacy classes of the group , with the first term corresponding to the identity element and the remaining terms forming a sum over the other conjugacy classes (which are all hyperbolic in this case). The function has to satisfy the following:\n",
"The left side is a volume in... |
what causes things to sound differently such as a breaking glass sound vs typing on a keyboard? | Sound is air vibrating. The air vibrates because it's being bumped into by a surface that's vibrating. Those surfaces have different characteristic amplitude and frequencies due to their materials, construction and size. So a large, flappy piece of paper is going to make very different vibrations than a big brick, when given similar energy inputs. Then the air in their vicinity is vibrated from the surface vibrating and different sounds are produced.
Think about it: How fast can you shake a marble back and forth? Can you shake a bowling ball at the same number of oscillations per second? (Well, yes, but the amount of energy required goes up in proportion to the mass). Or hit a bowl of jello with a hammer and hit a bowl of mashed potatoes with the same hammer. Which one jiggles more? At a microscopic level, that is what is happening to the air molecules that make the sound. | [
"An acoustic piano usually has a protective wooden case surrounding the soundboard and metal strings, which are strung under great tension on a heavy metal frame. Pressing one or more keys on the piano's keyboard causes a padded hammer (typically padded with firm felt) to strike the strings. The hammer rebounds fro... |
How was King Alfred able to beat the Vikings? | Honestly whole books and theses have been written on this.
I've written a little about it [here](_URL_0_).
For reading I would recommend Hill *et al*, *The Defence of Wessex*; Baker and Brookes, *Beyond the Burghal Hidage*; Reynolds *et al*, *Landscapes of Defence*; Stenton, *Anglo-Saxon England*; Lavelle, *Alfred's Wars* and *The Danes in Wessex* to start with. Our primary sources are *The Anglo-Saxon Chronicle* and Asser's *Vita Ælfredi*.
To put things very briefly: Viking warfare is based on rapid manouevre and avoiding fair fights as much as possible. As Asser recounts for the year 871, Wessex spends so much manpower chasing down small forced and defending against raids that when it comes to pitched battle, its forces are often outnumbered and exhausted.
Alfred's strategy comes from a mass overhaul, reform and bureaucratisation of the Anglo-Saxon defensive infrastructure. Potentially influenced by the fortified bridges over the River Seine to defend Paris from the Vikings that he would have witnessed on his childhood visits, as well as earlier English fortification networks from Offa's Mercia, the new *burghal* system essentially establishes a system of fortified garrison sites at roughly a day's march from each other at major road junctions, river crossings, bridges, landings etc. These severely limit the Vikings ability to outmanoeuvre the English, and instead allow an organised military reaction force to rapidly respond to Viking threats. | [
"In 878 King Alfred of Wessex defeated a Viking army at the Battle of Edington. Guthrum, the Viking leader, retreated with the remnants of his army to their \"stronghold\", where Alfred besieged him. After fourteen days the Vikings \"thoroughly terrified by hunger, cold and fear\" sought peace and sent an emissary ... |
What is human skin actually made up of? Is it technically a human organ? | An organ is a collection of tissues that perform a specific function. The skin is an organ that provides protection from the outside world to our viscerals.
There are three layers to the skin: the outermost **epidermis**, the **dermis**, and the underlying **hypodermis**. The epidermis is almost entirely keratinocytes arranged in five distinct layers; dead cells that slough off are constantly replaced by new cells pushing up from the lower layers of the epidermis. The dermis and hypodermis are layers of connective tissue and fat that physically and physiologically support the epidermis and protect the body. As such, these two deeper layers facilitate the routing of blood vessels and nerves to the skin, and provide the scaffolding for hair follicles, sebaceous glands, and sweat glands. The involvement of myriad cell types to make our skin function is what characterizes it as an organ. | [
"The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue and guards the underlying muscles, bones, ligaments and internal organs. Human skin is similar to most of the other\n",
"The skin is the largest organ in the... |
is this paper about roundup being dangerous legit? | > Consequences are most of the diseases and conditions associated with a Western diet, which include gastrointestinal disorders, obesity, diabetes, heart disease, depression, autism, infertility, cancer and Alzheimer’s disease.
That seems sketchy, just reading the abstract... | [
"In the \"In re: RoundUp Products Liability\" multidistrict litigation (MDL) a \"Daubert\" hearing was held in March 2018 on general causation as to non-Hodgkin’s lymphoma. This case consolidated over 300 federal lawsuits that allege Monsanto did not adequately warn consumers about the risks of using RoundUp. These... |
Are all galaxies eventually going to become spiral galaxies? | It's actually the opposite. Objects will collapse and choose a favorable direction (due to angular momentum conservation) only if there is significant friction during gravitational collapse so that kinetic energy is transformed into heat (and light). So disks only form if most of the matter is in gas rather than stars. If the material is already bound up in stars, there is no friction, so when the star falls to the center it just goes right back out - this is what elliptical galaxies are like.
When large spiral galaxies collide, the remaining gas forms stars in one huge burst and the stellar orbits are randomized. The resulting galaxy has no friction, so the stars orbit separately: the galaxy has become an elliptical. | [
"Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work \"The Realm of the Nebulae\" and, as such, form part of the Hubble sequence. Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. Th... |
how does isothermal clothing work? | Actually I don't think it does. it's just a marketing gimmick. usually, it's a base layer that's made to trap some air between your skin and the clothing (for insulation). in the old days, it was just little dimples they have grander schemes now and haven't found they work any better, it just allows them to use more plastic in the fabric. If they advertise isothermic then it should also lay out the rest of the system and the temperature range it's made to work in. Usually, I find the clothing that does give you the intended use, doesn't necessarily cater to the fashion market. | [
"BULLET::::- A \"sports towel\", or (synthetic) chamois, is a towel originally developed for swimmers and divers, favored for its super-absorbent qualities. Sports towels can be wrung out when saturated, leaving the towel able to absorb water again, although not dry. Those qualities, along with their compact nature... |
disney world is such a money maker, why are the cities surrounding it so poor with such a housing crisis? | Because that money does not go back to the local economy. It instead gets funneled to corporate accounts, and the corporate team doesn't live in these neighborhoods.
A company doing well only helps the local area if they put the money back in. For example paying workers well, ordering supplies from local companies, making donations to local charities, paying a fair amount of taxes.
What usually happens is that none of those happen. Workers get low wages, supplies are bought from the cheapest foreign supplier, donations are pretty often less than 0.05%, and they find ways to avoid paying taxes. | [
"The city is facing financial challenges. In late 2016, it had a major deficit in its budget and debts in excess of €400 million. \"In effect, the place is bankrupt\", according to a report by The Guardian. Many locals are leaving the historic center due to rapidly increasing rents. The declining native population ... |
Did radio have a reputation as being vapid or intellectually detrimental, the way TV does today? | I've only come up on this tangentially, but as it turns out: Yes, in the early 20th century there was a lot of opposition to radio as a form. As early as 1923 we start seeing anti-radio editorials such as an op-ed on the Times (of London), by one Douglas Hacking (then MP). In it, he calls "the wireless" a "maddeningly pedestrian diversion..." that is "sure to degenerate the minds of a generation of Britons." There were multiple bills introduced in Parliament that year calling for the defunding of the fledgeling BBC, and even the outright banning of radio in the UK. Though they were largely shelved due to more pressing issues at the time, it is notable that 1923-24 saw a brief fad in wearing pots or pans, or aluminium foil (Still a fairly new and expensive good at this time) on one's head while listening to the wireless, as those were thought to protect against brain degeneration - not even the threat of brain damage could keep the first generation of radio listeners away from the "simpleton box" as it was known! This was also a generational issue, of course; briefly during this period, youngsters were referred to as a generation of "twentieth-centurials" who were described (As one article in prominent American woman's magazine *The Delineator* put it) "self-centered, perpetual children more interested in the goings-on of the newfangled radio box than the real world around them." Twentieth-centennials were also portrayed as be selfish, ignorant, materialistic, lazy, and just generally no good compared to the heroic generation of WWI veterans that came just before them.
Across the pond, the radio was a target for the (rapidly dwindling) temperance organisations that were looking for a new thing to go after, having recently succeeded in getting Prohibition passed. Radio broadcasters were terrified of this, of course - if those temperance people could get Congress to outlaw *drinking,* what chance did the nascent radio broadcasters have? Radio broadcasters in New York, led by the venerable RCA, convened to develop the Hughes Code, a morality code for the radio, which was supposed to allay radio-borne brain damage (By 1925 a major issue in America's national conversation). The sedate, gentle style of Hughes code-era broadcasts is thought to have been a major influence on the early NPR and the genesis of public talk radio, too. By 1926, the panic seems to have subsided as radio became an accepted part of life in the Anglosphere, which is why the notion of putting a pot on your head to guard against radio-borne brain damage is so strange - it came and went in the popular culture very fast, though it remains in the use of "tinfoil" as a by-word for lunacy; that got mixed up in popular culture and stuck around, so much so that people are generally unaware of the very real use of aluminium foil to guard against brain damage in the twenties!
**This post was written as part of the AskHistorians 2014 April Fools' prank, and is therefore total nonsense.** | [
"Major technological innovations transformed the mass media. Radio, already overwhelmed by television, transformed itself into a niche service. It developed an important political dimension based on Talk radio. Television survived with a much reduced audience, but remained the number one advertising medium for elec... |
why do most bipedal robots always keep their knees bent a bit when standing? | I'm still an industrial electronics student but if I had to guess I would say that it is because when engineers program robots they are given a "home position" that the robot stays in. In this case the home position is the one that best allows the robot to react to varying conditions. Like if the robot were to step into a hole and the knees were locked straight it would have trouble being able to step down into the hole because that joint can't rotate any further. But if the knee is in the middle of its rotation then it can straighten to step down into the hole or rotate further to step up onto something. Basically it's the position that allows a robot to do as much as possible and as far efficiency goes we are still just getting the kinks worked out of getting a robot walking. So it's not the most efficient way to stand but it's the easiest. | [
"Legged robots can be categorized by the number of limbs they use, which determines gaits available. Many-legged robots tend to be more stable, while fewer legs lends itself to greater maneuverability.\n",
"Legged robots may have one, two, four, six, or many legs depending on the application. One of the main adva... |
how does the body "know" to try and reattach itself to a severed limb? | Uhm, it totally doesn't.
I'm having difficulty understanding what you are asking, exactly. Like, let's say I am trying to fix my lawnmower when a neighbor kid herpderps over and turns the motor on. Off goes my left hand.
My left wrist is NOT sending signals to my brain saying "Look! The hand is right there! Let's reattach!" All it's sending to the brain is "Holyshit, a lot a lot of tissue just got severely damaged ow ow ow ow ow," or possibly "Hot damn, you're losing a lot of blood. You should go into shock so you have a fighting chance of getting yourself to a hospital or something." Now, assuming you are not blind, your eyes *are* sending your brain the message of "Lookie, it's right there" and your brain, which has basically always had the will to live, hatches a plan saying "I gotta put this on ice and take it to the ER immediately" and then carries that out.
Potentially you are trying to ask "Once the doctor puts the hand back in place and sews things up, how do the tissues on the hand "know" to line up properly and attach themselves to the tissues in the wrist?" Well, again, they don't. The tissues in your hand and wrist, provided they are getting adequate assistance from the body (enough blood flow, platelets, infection-fighting white blood cells) will try to heal the wound any way they can. Scabs and equivalent connective tissues will be made by your body and then eventually skin and permanent tissue will grow around/under it until the scabs can go away. If my hand is obliterated in the lawnmower, the end of my wrist will STILL try to scab and heal itself, it will just end up as a nub. If, however, my hand happens to have been professionally medically put back in the right place, then when my body starts scabbing/rebuilding, it will encounter my hand, and the reattachment process will include it. This is also why skin grafts work. The body is scabbing up, and will scab up against whatever is there, an in the case of skin grafts it goes "Oh how convenient! More skin to scab up against!" and continue doing its thing. If the doctor effs up the alignment, my body will not just gloss over the error and make everything be hunky-dory again because he was "close enough." I'm gonna lose that hand. And in fact, I probably will anyway. The bigger or more complicated the part you are reattaching is, the less likely it will be to reattach successfully. | [
"During the procedure, the person is under regional or general anesthesia. A surgical tourniquet prevents blood flow to the limb. The skin is often opened with a zig-zag incision but straight incisions with or without Z-plasty are also described and may reduce damage to neurovascular bundles. All diseased cords and... |
how does anxiety cause one to experience feeling unattached to one's body, or "derealization"? | It's a coping mechanism; really short answer, dissociation/derealization is a defense mechanism to deal with stress or trauma. Not being there = not having to deal with the stressful situation. If you need me to expand on it I can. :o
Source: I have severe dissociation and dissociative identity disorder | [
"Auras can also be confused with sudden onset of panic, panic attacks or anxiety attacks creating difficulties in diagnosis. The differential diagnosis of patients who experience symptoms of paresthesias, derealization, dizziness, chest pain, tremors, and palpitations can be quite challenging.\n",
"The biological... |
why the value of so many western currencies is roughly equal? | Many of these currencies are or were pegged to the USD after WWII. Since the United States had the vast majority of the world's gold (lend-lease was expensive, as it turns out), the agreement was that the USD would be backed by gold and the other currencies would be backed by the Dollar. (The [Bretton Woods](_URL_0_) system)
In fact, France and Switzerland actually followed through on this, redeeming their reserve USD for around $250 million in gold in the late 60's. This of course prompted Nixon to make the Dollar free floating, backed by nothing in particular. (The Nixon Shock)
Since the Euro and Australian Dollar were created after this system, it made sense to value them around 1:1 with the USD. The Pound Sterling and the Swiss Franc were initially valued at around 4:1 with the dollar, but the post war economic boom in America rapidly increased the relative value if American dollars, bringing them more in line with each other.
The Canadian dollar, on the other hand, was pegged at 1.1:1 in the 40s and has been slightly less valuable ever since.
TL;DR: America had all the gold after WWII and made the rules. | [
"The major currencies (except the Japanese yen) are traditionally priced to four decimal places, and a pip is one unit of the fourth decimal point: for dollar currencies this is to 1/100th of a cent. For the yen, a pip is one unit of the second decimal point, because the yen is much closer in value to one hundredth... |
How would schizophrenia manifest itself in someone who was deaf or raised isolated from language? Would the voices be manifested elsewhere in their sensory system? | Here are a few things to consider:
(1) If a deaf person has visual hallucinations of someone signing to them, this is not equivalent to having delusional thoughts in sign language. In schizophrenia, delusions can arise with or without hallucinating voices or signs, and these delusions have more to do with cognition than perception [(Cuesta & Peralta, 1995)](_URL_0_).
(2) In people who are born deaf, the auditory cortex is recruited to handle processing for other perceptual modalities [(Lambertz et al., 2005)](_URL_2_); therefore, it is unlikely that abnormal activity in the auditory cortex of a congenitally deaf person could manifest auditory hallucinations, and would more likely manifest hallucinations in other modalities.
(3) If someone has never perceived sound, their concept of hearing is solely based on how the experience has been described to them. Even if the random firing of auditory neurons somehow elicited auditory hallucinations in a congenitally deaf person, it would be very difficult to recognize these sensations as sound because they would not correspond to any previous experience [(Mishkin & Murray, 2003)](_URL_3_).
(4) In cases where people with schizophrenia become deaf later in life, whether or not they would continue to experience auditory hallucinations depends on the cause of their deafness; if caused by damage to the basilar membrane, auditory hallucinations would likely persist, but if a stroke destroyed the auditory cortex, they would likely cease to occur [(Lennox et al., 2000)](_URL_1_).
| [
"Another typical disorder where auditory hallucinations are very common is dissociative identity disorder. In schizophrenia voices are normally perceived coming from outside the person but in dissociative disorders they are perceived as originating from within the person, commenting in their head instead of behind ... |
why does eating more frequently increase your appetite? | Simple. You stomach is elastic. Eating a lot causes it to stretch and grow. Not eating a lot causes it to shrink. Your appetite always drives you to fill your stomach, whatever size it currently is, so if you eat a lot, it take more food to fill it since you are stretching it out (and I think it grows if it stretches a lot.) | [
"Appetite is the desire to eat food, sometimes due to hunger. Appealing foods can stimulate appetite even when hunger is absent, although appetite can be greatly reduced by satiety. Appetite exists in all higher life-forms, and serves to regulate adequate energy intake to maintain metabolic needs. It is regulated b... |
How does blue and red shift of a star occur if light is constant? | The wavelength and frequency both change, while the light maintains a constant speed.
The speed of a wave is equal to the length of a wave from peak to peak times the frequency, or how often a peak passes you as the wave travels by. Redshift corresponds to lower frequency and longer wavelength, and vice versa for blueshift. | [
"As the main star rotates on its axis, one quadrant of its photosphere will be seen to be coming towards the viewer, and the other visible quadrant to be moving away. These motions produce blueshifts and redshifts, respectively, in the star's spectrum, usually observed as a broadening of the spectral lines. When th... |
Why no aerial oxygen torpedoes for the Japanese? | The Japanese did develop an experimental oxygen-propelled aerial torpedo, the Type 94 in the early 1930s in parallel with the oxygen-propelled Type 93 and Type 95. The Navy Technical Arsenal found that the Type 94 was too complicated and maintenance- intensive for an aerial weapon. The main advantage of an oxygen torpedo- range- was not nearly as important for aerial attacks, especially since aircraft often lacked the sophisticated and heavy fire-control equipment surface ships and submarines possessed to successfully carry out an attack at distance. Although the Yokusuka and Nagasaki Arsenals produced between 100-200 Type 94s, the Japanese soon went back to conventional aerial torpedoes. The IJN would not revisit the possibility of oxygen aerial torpedoes in no small part because its standard aerial torpedo, the Type 91, gave sterling performance. The Type 91 was superior in performance to its American counterpart at the start of the Pacific War and their anti-roll stabilizers allowed the torpedo to better hit their target. The only serious wartime modifications of the Type 91 was replacement of bronze parts with steel and minor alterations that eased production and boosted performance, with the resulting simplified torpedo, the Type 4, entering production in 1944. | [
"The oxygen Long lance torpedo, which used pure oxygen instead of air for the oxidizer, was developed by the Japanese just prior to their full involvement in WWII. Despite having more than twice the effective range of the best Allied torpedoes and lacking the tell-tale torpedo wake, the oxygen torpedo was not used ... |
do wifi signals face resistance when passing through walls? | Yes, but walls aren't always the big issue!
Waves can be absorbed by walls, reflected off of surfaces like windows and metal panels, and they can be grounded really easily.
I used to do a bit of RF work and we found the biggest thing that hampered us was either metal fences (didn't matter that they're full of holes, they act like antennas and ground the shit out of it) and even trees, which behaved similarly.
Often times walls (even fairly thick ones) aren't the biggest deal breaker. | [
"It's practical in some cases to apply specialized wall paint and window film to a room or building to significantly attenuate wireless signals, which keeps the signals from propagating outside a facility. This can significantly improve wireless security because it's difficult for hackers to receive the signals bey... |
how exactly does a power strip work? | The outlets in a power strip are wired up in parallel. As you plug more items in the load does increase. Most power strips have a circuit breaker on them that will trip if you exceed the load, if not your outlet should have a circuit breaker as well. It is entirely possible to overload a power strip, it is just most consumers don't have that many high draw items in one area and professionals such as contractors already know better. | [
"A power strip is a block on the end of a power cable with a number of sockets (usually 3 or more), often arranged in a line. This term is also used to refer to the whole unit of a short extension cord terminating in a power strip.\n",
"A power strip (also known as an extension block, power board, power bar, plug... |
how are our intestines able to sort between gas, liquids and poo? | Liquid is extracted by the large intestine. Essentially the large intestine has chemical pumps that take advantage of osmosis to force water out of the intestines and into the body. Salt is pumped into the liquid between the cells and this causes osmosis to push water into that liquid and from there the bloodstream.
This leaves solid wastes and gases (which comes from swallowed air and gut bacteria). The large intestine has nerves in it, which essentially allows us to feel what's in our large intestine. Gas and solid waste behave differently and over time we learn to feel the difference. | [
"Digestion occurs in the intestine, with the caecum producing further digestive enzymes. An additional tube, called the siphon, runs beside much of the intestine, opening into it at both ends. It may be involved in resorption of water from food.\n",
"The small intestine is the part of the digestive tract followin... |
how does a surveying work? | Basically it is a measuring device to measure angles and distances, and elevation.
So a building is designed on a computer model of the site. You need a way to take that electronic information and place it on the real ground so the guys actually building the building know where to build the building, or the new road or whatever.
The thing on the tripod is kinda like a telescope, it has cross hairs and can measure very precise angles and distances, the newer ones are robotic and use gps.
Surveying also works the opposite way, you can measure stuff on the ground and recreate it electronically on a computer. | [
"Surveying or land surveying is the technique, profession, art and science of determining the terrestrial or three-dimensional positions of points and the distances and angles between them. A land surveying professional is called a land surveyor. These points are usually on the surface of the Earth, and they are of... |
Will swirling my coffee in it's cup cool it down faster, slower, or have no impact? | faster, the coffee is in contact with more of the cups surface area, plus more evaporated cooling, and mixing the hottest coffee at the top with the coolest from the bottom. If you're using a metal spoon, it'll absorb some heat too. | [
"When placed beneath a cup, saucers have very little direct influence on beverage cooling rate. For hot, water based beverages (e.g. tea or coffee), cooling rate in a cup is typically dominated by evaporation, which occurs across the free surface in contact with the air. Heat transfer through the bottom of the cup ... |
why does it take some people longer than others to be alert upon waking? as in, why does it take some people longer to really "wake up"? | Cortisol production also has to do with this. Some people make more cortisol in their sleep. These people tend to appear to "snap awake"... _URL_0_ (edit: I just woke up and forgot to link to the wiki-sauce). | [
"Today, many humans wake up with an alarm clock; however, people can also reliably wake themselves up at a specific time with no need for an alarm. Many sleep quite differently on workdays versus days off, a pattern which can lead to chronic circadian desynchronization. Many people regularly look at television and ... |
the artistic value of rothko's orange, red, yellow painting | Like everything else, something is worth what another person is willing to pay for it. A sub that focuses on art work might be a better place. | [
"Souren Melikian of \"The New York Times\" described Rothko's \"Orange, Red, Yellow\" as one that \"...can convincingly be argued to be the most powerful of all his pictures\", Kelly Crow of \"The Wall Street Journal\" stated that \"The painting's trio of orange and yellow rectangles bobbing atop a cherry-red backg... |
What is the current historiographical opinion regarding Henri Pirenne's: Muhammad and Charlemagne. | In a nutshell (because the non-nutshell version would stretch across several already written books):
What holds:
* The Arab Conquests absolutely cemented (as one could argue that the Persian conquests did their number already) the breaking of the Mediterranean economic system, with catastrophic effects on the urban and political structure of what was left of the Eastern Roman Empire, as well as causing economic regression in southern France, which at the time was still somewhat integrated with the Mediterranean network.
What doesn't (keeping in mind almost all of Pirenne's ideas were pre-archaeological):
* Pirenne uses documentary luxury trade evidence as a marker for economic vitality in the pre-Arab conquest Mediterranean. More modern analysis uses pottery, which shows a drastic reduction in volume and regional scope of trade even before the Arab conquests.
* He overestimates the vitality of North Sea trade. Though it clearly started growing in the time of Charlemagne, in Pirenne's visualization it was already something akin to a proto-Hanseatic League that continued on into the high Middle Ages. Later archaeological digs have found that North Sea trade quickly collapsed after the death of Charlemagne, taking a few centuries to return to the same level.
* His idea of Germania as Romania is too much of an overextrapolation of "possible" de jure Roman authority rather than a reflection of the power situation on the ground, which is that the Germanic successor states were already so heavily regionalized that Constantinople had at best a distant legitimizing influence akin to what the Queen of England has on the policies of Commonwealth (and ex-Commonwealth) nations, which is to say almost nil.
With that said, Pirenne has absolutely been used as the starting point for analysis of the period, and I would dare say that Peter Brown's promotion of the phrase "Late Antiquity" over "Early Medieval" is a direct consequence of Pirenne's theory.
(Though with that said, Late Antiquity clearly has a Mediterranean connotation, whereas Early Medieval is much more Western Europe. I have yet to find a periodization name that suitably covers the entire post-Roman European/Mediterranean/Near Asian transition.)
What's really interesting is that despite Pirenne's flawed thesis, it has had an amazing durability as a start point, so much so that it's taken until the last 10 years for anyone to come up with an alternative framework for the entirety of post-Roman transition.
Best as I can tell, the only person so far (who has explicitly said he has sought to create a new framework beyond Pirenne) would be Chris Wickham, in his book "Framing the Early Middle Ages." I've seen this book cited everywhere, even as far as East Asian studies on state economic structures.
In yet another nutshell, he tries to reorient the discussion away from specifically the Arab conquest break in Mediterranean trade, and more toward the collapse (or survival) of regional taxation as a key to the survival of a post-Roman state.
Yet despite his explicit statement of seeking to establish a new paradigm (god I hate that word, but I can't find anything else in the thesaurus), he plainly acknowledges the debt owed to Pirenne for coming up with an economic, as opposed to a purely political (barbarians took over the leadership), reason for Roman collapse.
Only thing about the book, is despite its solid scholarship, you see particular Marxist interpretations pop up every now and then. For example, in the idea that the demographic collapse of Europe was due to voluntary peasant population reduction. Or the assumption that peasants would prefer a life of poorer autonomy to one of relatively greater material wealth but under subjection. I also have issues with his suggestion of monolithicness (and this may just be the nature of Marxist philosophy) of aristocratic attitudes toward the peasantry, as well as vice versa.
But other than these criticisms, no one debates the quality of the scholarship and subsequent analysis. His examples regarding state collapse or survival are useful enough to be extrapolated or tested elsewhere, which is why you're seeing it in other areas like East Asian, which is attempting to see if his theory holds up with regards to state survival/collapse in that region.
Back to Pirenne. One thing of note that I've read recently. The Pirenne quote "without Mohammed, Charlemagne would be impossible" is seen quite often, however it is extrapolated for a wide range of purposes. It should be remembered that the context of that quote in Pirenne's book is specifically religious (the need for a Christian antipode to Islamic caliphs), as opposed economic (i.e. the breaking of mediterranean unity by the Arabs), despite the obvious economic repercussions Mohammed had on the emergence of Charlemagne.
Hope this helps, let me know if you have any other questions. | [
"In a summary, Pirenne stated that \"Without Islam, the Frankish Empire would probably never have existed, and Charlemagne, without Muhammad, would be inconceivable.\" That is, he rejected the notion that barbarian invasions in the 4th and 5th centuries caused the collapse of the Roman Empire. Instead, the Muslim c... |
what is "dutch disease"? | The Dutch can breathe easy, because, contrary to popular belief, Dutch disease is not a flesh-eating disease in the Netherlands.
It's an economic term used to describe an indirect relationship between the usage of natural resources and agriculture. Exploitation of natural resources increases, agriculture declines. Now, why is this? Because the more and more money you make from natural resources, the stronger a country's currency can be compared to other nations. Because of this, a country's *other* exports become more expensive for different countries to buy, which makes the agricultural market much less competitive, thus causing a decline in the sector. | [
"The Dutch term usually specifically refers to the wave of disorderly attacks in the summer of 1566 that spread rapidly through the Low Countries from south to north. Similar outbreaks of iconoclasm took place in other parts of Europe, especially in Switzerland and the Holy Roman Empire in the period between 1522 a... |
what is canon? | The term was largely used when referring to the Bible. The many authors whose writings appear in the Bible wrote many other things as well. The pieces deemed "The Bible" were democratically selected by high ranking clergy. These are referred to as "Canon", while the many other writings of biblical authors are deemed "apocrypha" and most religions basically think that the canonical writings are inspired by God and for some reason that the apocryphal texts were not. They were mostly excluded because clergy didn't like what they said.
Anyways, "canon" is used to refer to the "official" part of a story, while other related texts that take place in the same world but aren't "official" are "apocryphal". For example, many authors wrote stories that took place in the Star Wars universe, but George Lucas didn't read and approve every word, so they are consider non-canonical. | [
"Canon law is the body of laws and regulations made by or adopted by ecclesiastical authority, for the government of the Christian organization and its members. It is the internal ecclesiastical law governing the Roman Catholic Church, the Eastern and Oriental Orthodox churches, and the Anglican Communion of church... |
why obama is criticized for going golfing? | It's part of the partisan bickering that comes with a two party system. If the President is a member of your party and takes a break, he's been working really hard and deserves it. If he's a member of the opposition, he's a lazy bum. | [
"In an October 3, 2011, interview with Fox News Channel's \"Fox & Friends\", Williams referred to a June golf game in which President Barack Obama and Republican House Speaker John Boehner had teamed against Vice President Joe Biden and Ohio Governor John Kasich, saying the match was \"one of the biggest political ... |
how can windmills compare to nuclear powerplants, where the generators spin with thousands of rounds per minute? | Windmills produce less power, that's why you build more of them | [
"For large, commercial size horizontal-axis wind turbines, the electrical generator is mounted in a nacelle at the top of a tower, behind the hub of the turbine rotor. Typically wind turbines generate electricity through asynchronous machines that are directly connected with the electricity grid. Usually the rotati... |
how does "trading futures" work? i've been told it's a good and cheap way to play the stock market, but everything i've read on it confuses me even more. | So I come up to you and say I will deliver to you, a ten pound ready-to-eat turkey on November 22nd if you give me $50 right now... and you think "that's a good price" and you give me fifty bucks.
I have just sold you a future comodity or service. We have just performed futures trading.
Now I've sold you that promise. I owe you a Turkey. But I don't have a turkey yet. And if I had a ready-to-eat turkey right now then it'd be inedible in six months anyway.
So I have six month's to arrange for a turkey to show up at your door on the 22nd. If I can make it happen for under $50 then I made a profit. If it costs me $65 then I lost 15 bucks.
Now lets move to something that could survive six months. Something like a barrel of oil. If I have someplace to store that barrel of oil _and_ I have a way to deliver that oil, then I can buy it at any time and store it.
So I sell you a barrel of oil for November delivery, for $50 right now. I am betting that sometime between now and then I can get that barrel for less than $50. And Ideally I can just go and have the oil guy deliver "my barrel to you" at the requested time.
So you can go out and arrange for your power plant or refinery to receive 500 barrels of oil a day for all of the foreseeable future, weeks, months, or even years in advance. And the people you bough it from already got the money and are on the hook. If you've got a year's worth of oil lined up at $50 a barrel and the prices rise to $100 a barrel it's my problem not yours.
Other things can work this way too. You can buy my winter corn crop today. I promise you 1,000 bushels of corn and you give me money. I use that money to buy the seed now and grow the corn. I'm on a hook for that 1,000 bushels, it's already sold. But if I can produce more, or produce it for less than you paid, then I make money.
So "futures" are bets on future prices and availability. If I think something is going to be cheap and you think it'll be expensive, you buy from me at a price that's less than you think it will cost, and a price that I think is high. ~~And if we are both right we've spread the risk and the reward.~~ (EDIT: we can
t both be right enough to make a split profit.) Its essentially impossible for us both to be right or wrong at the same time.
So most of the stock and commodities markets are just bets. Seller is betting the price will go down, buyer is betting the price will go up.
Short sales and futures sales are just making the bet before you have the item on hand.
("Short Sales" is sort-of like futures trading. Your broker lends you stock to sell right now, and you have to return that stock by buying some of that same stock by a fixed future date _and_ you have to pay a fee for the loan. But both are about selling things now that you'll have to buy in the future. The flaming disasters happen if, by that future date, _nobody_ is selling what you need to buy to make good on your promises.)
It's higher risk. (What happens if all the corn dies from blight?) but that risk _can_ net higher rewards.
It's only cheap for as long as you don't lose big. | [
"Prices in futures markets play a special role in economic calculation. Futures markets develop prices for commodities in future time periods. It is in futures markets that entrepreneurs sort out plans for production based on their expectations. Futures markets are a link between entrepreneurial investment decision... |
how does the brita filter detector work? | it counts the number of times you tip the pitcher. it assumes that on average each time you tip it forward another glass of water has been poured out (and the LED will blink). the filter life is about 40 gallons, so it predicts when you've gotten close to the end of the useful life of the filter.
when the yellow LED starts to blink you have about 2 weeks use (on average) left. which means you should have another filter ready.
when the red LED blinks each time you've reached the average useful life for the filter. of course its all pretty imprecise, and it varies depending on whats in your water (sediment or hard water will cause the filter to become too slow to use sooner).
in any event, after two months they suggest you replace the filter.
BTW: you only need to press the RESET button when you install a new filter, not each time you refill the pitcher with water. | [
"An organ-pipe scanner is a system used in some radar systems to provide scanning in azimuth or elevation without moving the antenna. It consists of a series of waveguides and feed horns arranged in front of a shaped reflector, each one positioned to reflect the beam in a different direction. The wave guides meet a... |
how bi-planes are able to time/shoot their guns without the bullets hitting the propellers. | While all of the responses so far are good (the wiki link explains quite well in-depth, with illustrations), I'd like to try making this as ELI5/TL;DR as I can:
The pilot's trigger is not really the same as a trigger on a handgun - it does not make the weapon fire. Instead, it works more like a safety - when pressed down the safety is off. The trigger is attached to the propeller - the propeller will pull the trigger each time it is in a position where the bullet will miss. | [
"Machine Gun turrets have a relatively low ceiling, given a turret at a reasonable elevation, an aircraft would likely be able to fly above the bullets unscathed. They are quick to fire, sending up bursts of 5 bullets at a faster rate than aircraft machine guns at quick, regular intervals. Depending on the aircraft... |
Are there any accounts of interviews with people who participated in lynchings 20, 30, or 40 years later? | Yes, contemporary interviews exist documenting the perspectives of those who participated, witnessed, in rare cases even those that survived lynchings. Interviews taking place some decades later are more difficult to find, but can be found in a few cases.
A powerful example comes from the [lynching of two men in Marion, Indiana](_URL_0_), in August 1930 [link NSFW]. The two men were accused of raping a white woman, the typical crime associated with lynching. A third man also accused of the crime was to be hung alongside them, but the crowd spared him at the last minute. The survivor told his story in an interview sometime in the 2000's. It makes for a powerful account - you can find it [here](_URL_2_).
Interviews from perpetrators of these crimes are more difficult to find, especially in the decades after the passage of the major civil rights acts authorizing federal prosecution even decades after the crimes were committed. One major and famous exception involved perhaps America's most infamous lynching - the murder of [Emmett Till](_URL_3_) in 1955. After an all-white jury found Roy Bryant and J. W. Milam innocent, they [told their story](_URL_4_) to *Look Magazine* and in the interview the two essentially admitted to the murder. [Double jeopardy](_URL_1_) prevented future prosecution. | [
"The documented murders of 4,743 people who were lynched in the United States between 1882 and 1968 were not often publicized. It is likely that many more unrecorded lynchings occurred during and after this period which influenced The Great Migration of 6.5 million African Americans away from southern states. A 197... |
why is it unhealthy/more difficult for hunger’s sake to eat a 2000 calorie breakfast instead of lighter meals throughout the day? | Your body doesn't need 2000 calories all at once. If you eat a single 2000 calorie meal, then your body will use however many calories it needs at that moment, and then store the rest as fat to be used later. However, when you need calories a few hours later, it won't immediately dip into your fat reserves. Instead it makes you feel hungry. Your body would rather turn fresh food into energy than stored fat.
| [
"Breakfast, in particular, has been found to have a beneficial effect on children’s study, behaviour, and attendance and there is mounting evidence that eating a good quality breakfast reduces the risk of obesity. \n",
"BULLET::::- The Academy states that children who eat breakfast have better concentration, prob... |
Would it be possible to create helium-4 by introducing helium-3 to a neutron rich environment? | Yes, but this wouldn’t be a very good way of doing it. Most helium in nature is helium-4. So you’d have to gather helium, enrich it with helium-3, and then use the helium-3 to breed helium-4. Unless you have a source of helium which is already enriched in ^(3)He, and want to convert it to ^(4)He for some reason. | [
"Not all authors feel the extraterrestrial extraction of helium-3 is feasible. Dwayne Day, writing in The Space Review, identifies some major obstacles to helium-3 extraction from extraterrestrial sources for use in fusion, and questions the feasibility of extraterrestrial extraction when compared to production on ... |
why is it scary when kids sing or laugh or say nursery rhymes in horror movies/games? | Generally, it's done in a minor key where the tune is altered, so anything can be spoopy when done that way (Have you seen the Teletubby episode in black and white that plays a Joy Division Song over it?).
Also, one of the early films to do this was Nightmare on Elm Street where kids are jumping rope and singing 1-2 Freddy's coming for you, 3-4, better lock your door.
In this case, it's contextual. Freddy Kruger was a child molester and murderer, so it's about dead kids, and the context makes it spoopier. | [
"Nursery rhymes are short songs written for small children. The lyrics are usually simple and repetitive for easy comprehension and memorization. Although they are meant to be lighthearted and fun, they also function as an introduction to music and certain basic concepts learned through repetition and song. \n",
... |
Can electrons from a particular atom be anywhere in the universe but statisticaly nearly always in a definite zone near the core or there is places those electrons can't be? | Electrons can not exist within nodes. The number and shape of nodes is dependent on the orbital angular momentum. | [
"If these two electrons are correlated, then the probability of finding electron \"a\" at a certain position in space depends on the position of electron \"b\", and vice versa. In other words, the product of their independent density functions does not adequately describe the real situation. At small distances, the... |
Is squinting actually bad for your eyesight? | I don't know if it's bad for your eyesight or just a sign of bad eyes. Squinting will improve peoples vision slightly if they have bad eyesight which is why you might see people do that if they lost their glasses. Because of this reason it might have also made people think it was the cause of them needing glasses when it was simply their body compensating for their bad vision up until they got glasses.
Also, squinting can help protect your eyes. Squinting in bring light is your bodies response to light so bright it could harm damage your retina. Squinting will limit the amount of light entering your eyes preventing/limiting damage until your eye compensates by making the iris smaller or until the light source is removed. | [
"It is a common belief that squinting worsens eyesight. However, according to Robert MacLaren, a professor of ophthalmology at the University of Oxford, this is nothing more than an old wives' tale: the only damage that can be caused by squinting for long periods is a temporary headache due to prolonged contraction... |
Operation Barbarossa caused massive Soviet casualities/incredible success for the Germans yet failed in capturing Moscow or force a surrender, was there a glaring tactical error that prevented this? | Logistics.
The campaign didn't start "late": the early summer months in Russia see significant rainfall, resulting in the so-called *rasputitsa*, literally "time without roads". Barbarossa's launch was timed so the ground could dry and the roads become usable again. In 1941 only 40,000 miles of the Soviet Union's 850,000 miles of road were hard-surfaced and suitable for use in all weathers. In the event, the roads were still atrociously bad. Most were little more than dirt tracks, which became rivers of glutinous mud after a summer downpour. These quickly became impassable quagmires to thousands of marching men, horses and vehicles. The roads were so bad that at one point it took the 7th Panzer Division two days to advance 90 kilometres. When they dried, they became rutted and treacherous, ready to turn an ankle or break an axle, and kicked up great clouds of dust that choked man, beast and machine alike: as well as being intolerable for men and horses, vehicles broke down at an alarming rate as filters were clogged and engines suffered dust contamination.
In such conditions, POL (Petrol, Oil, Lubricant) consumption accordingly rocketed: LVII Panzer Corps reported in August that its vehicles were consuming up to 30 litres of oil per 100 kilometres rather than the usual half-litre of oil. Even the few paved highways soon became unsuitable for large military movements because the ground they are built on was so poor: as early as two days into the campaign, XXXXVII Panzer Corps was delayed in crossing the Bug River because the surfaces of the approach roads were literally sinking into the sodden ground under such heavy weight of traffic.
Then there were the Germans' vehicles themselves: there was a critical shortage of trucks. The deficit was somewhat made up by thousands of captured French Army and requisitioned civilian vehicles, but these were very rarely 4-wheel drive models and were quickly ridden to destruction on the horrendous roads. Where there were no motor vehicles, horses were used: an infantry division had an establishment strength of 942 motor vehicles compared to 1,200 horses, while the *Ostheer* invaded the Soviet Union with a total of 625,000 horses. A horse cart is unlikely to travel more than thirty kilometres a day and no more than five kilometres in an hour, to say nothing of horses' vulnerability: they are easily incapacitated by colic caused by poor feeding, infections picked up from contaminated water, or severe cold. Within a year of Barbarossa being launched, fully half of the *Ostheer's* horses had perished.
The perception gained from looking at maps that the *Ostheer* nearly took Moscow conceals the fact that the offensive had reached its culminating point around Smolensk: the German logistic system was incapable of sustaining an advance more than 500 kilometres from railheads. After this point, it would have to stop and redress its lines of communications before it could hope to make the next bound. It *tried* to do this, but Stalin was in no mood to give the Germans the luxury of a pause and hammered their positions at Smolensk with relentless counteroffensives. There was no opportunity to tidy up supply lines because those very same supply lines had to supply troops desperately trying to fend off the counteroffensive. There was no particular tactical flaw that doomed Barbarossa (though many German Generals subsequently tried to blame Hitler for focusing on Kiev and the Ukraine before taking Moscow); it was flawed from the beginning owing to the impossibility of sustaining it.
Sources:
Robert Kirchubel, *Operation Barbarossa: The German Invasion of Soviet Russia*
Robert Kirchubel, *Atlas of the Eastern Front*
David Stahel, *Operation Barbarossa and Germany's Defeat in the East* | [
"In 1941 it was Russia's turn, yet Joseph Stalin refused to believe the multiple warnings of a German invasion. Operation Barbarossa began in June 1941, captured or destroyed multiple Soviet armies, and reached the gates of Moscow by December. Stalin fought back and forged close relations with Britain and the Unite... |
How much of an impact did the Civil War have on what is considered the Wild West? | You're gonna have a hard time getting any kind of a comprehensive answer to this question, as it's just too broad of a topic. It would be like asking, "what kind of an impact did World War II have on America in the second half of the 20th century?" The question itself is so open-ended and complex that you could run in any number of directions trying to answer it.
For example, one could write at great length at how the role of women changed in American culture, specifically west of the Mississippi River, following the Civil War. One could go on for ages talking about the evolution of racial opinions and ideals out "West" following the Civil War, and how ideas of "whiteness" came into focus in a sort of mass hegemony that eventually eliminated notions of "German," "Dutch," or "Italian" in favor of just "white." How do you define "West," too? Is it by time period as well as region, and if so, what region and what time period?
I don't mean to discourage discussion, but it might help to focus your question into something that's a bit more digestible. You mention how the war affected people going west, and "the general politics of the era." What politics are you referring to? State or federal, and in relation to what? | [
"The image of a Wild West filled with countless gunfights was a myth generated primarily by dime-novel authors in the late 19th century. An estimate of 20,000 men in the American West were killed by gunshot between 1866 and 1900, and over 21,586 total casualties during the American Indian Wars from 1850 to 1890. Th... |
I have a very specific question about the death of our star and supernovae (s?). Please look inside for details. | Without having many details at hand, and I'm sure someone can explain the fusion process better that I, Supernova are after all fusion has expired and caused by the mass of the red giant collapsing in on itself. this compression effectively blows the star apart (core-bounce) which is what a Type II Supernova is. so the earths core wouldn't make any difference to that process. However our Sun is just too small to become a Supernova anyway and it is destined to be a white dwarf. Only stars with sufficiently high mass become a full supernova. | [
"Supernovae can result from the death of an extremely massive star, many times heavier than the Sun. At the end of the life of this massive star, a non-fusible iron core is formed from fusion ashes. This iron core is pushed towards the Chandrasekhar limit till it surpasses it and therefore collapses.\n",
"WR star... |
How common was circumcision among the Pre-Islamic Arabs? We can safely assume that Christian tribes, namely the Banu Hanifa and the Banu Taghlib , would have abhorred the practice, but what about the rest? What about the Quraysh? | Tangential question, why would assume those Christian tribes would abhor it? | [
"Although there is some debate within Islam over whether it is a religious requirement, circumcision (called \"khitan\") is practiced nearly universally by Muslim males. Islam bases its practice of circumcision on the Genesis 17 narrative, the same Biblical chapter referred to by Jews. The procedure is not explicit... |
Are animals attracted to each other’s faces the way humans are? | Depends, i would assume some focus on colors, others on the rear-end etc... They haave specific evolutionary traits they look for.
Not all humans look at faces either, or find different types of faces attractive | [
"A major way that people relate to mammals (and some other animals) is by anthropomorphising them, ascribing human emotions and goals to them. This has been deprecated when it occurs in science, though more recently zoologists have taken a more lenient view of it.\n",
"Expressions of affection are displayed in th... |
If the earth's core cooled and solidified, would the planet get appreciably smaller? And if so, by how much? | Couldn't tell you exactly, but here's some estimates that are beyond rough. I'll have to make lots of assumptions.
Assuming we don't talk about condensates and such, then all material changes density depending on temperature. So I have to assume that we're only talking about the liquid core changing just barely enough to solidify. Also have to assume that this is possible even under the heating effects of gravitational contraction.
We also have to assume that current ideas of earth composition are correct - so there is the solid core center which is not changing in our thought experiment here, but the liquid outer core is cooling.
Next we have to assume that the liquid core is made of mostly iron, with about 4% nickel, and something else that lowers the density by about 10% by mass. So we can't do any calculations correctly unless we just assumed pure iron.
Next we have to assume that we know the temperature of the liquid core, which we don't. So for this experiment let's assume the liquid core is just barely liquid and is almost turned solid.
Next we have to assume that the compression of gravity and outer layers is not compressing the outer core significantly (or at least that the compression stays the same upon solidifying).
Next we have to assume a mass for the outer core. I found calculations ranging from 1.603x10^24 kg to 1.928x10^24 kg. Let's assume an average of 1.765x10^24 kg.
So if the density of molten iron is 6.98g/cm^3 then the molten core would occupy 2.52865x10^20 m^3.
At this point you'll have to forgive me for getting lazy. I don't know the density of iron at it's freezing point, only at room temperature. So We can assume that whatever expansion or contraction that happens from the molten point to room temperature will be consistent and in one direction - either smaller or larger. So if the mass stays the same and the density of solid iron at room temperature is 7.874g/cm^3 then the volume of the now solidified core would be 2.24155x10^20 m^3. That's a difference of 2.871x10^19 m^3 or 2.871x10^10 km^3
So if we assume the current volume of the earth is 1.08321x10^12 km^3 then after the cooling the volume would be 1.0545x10^12 km^3.
The current radius of the earth is 6371 km. After cooling the new radius would be 6314 km.
I think if the surface of the earth dropped 57 km we might notice it. | [
"The Earth's inner core is thought to be slowly growing as the liquid outer core at the boundary with the inner core cools and solidifies due to the gradual cooling of the Earth's interior (about 100 degrees Celsius per billion years).\n",
"The growth of the inner core may be expected to consume most of the outer... |
can someone explain elasticity of demand and how it relates to the price of crude oil and other commodities? | I'll do my best, though I have a somewhat ameturish knowledgebase myself. Explaining it **like you're five**.
Lets say that you own a store. You want to have customers, so you set nice and low prices. It works and people come and buy your stuff. This is great but you need to make some money.
You want to find out: If you raise the price by a little bit, will your customers still want to buy it? So you do some asking around.
For some things, like bottled water, people are OK with paying a little more.
On paper clips, people are totally against it and won't buy from you.
To wrap up the analogy, the demand for the bottled water would be "inelastic," because people still wanted it after the price went up.
The demand for paper clips would be "elastic" because people weren't as willing to pay the higher price.
We use those terms because if someone wants something less because the price is higher, they're flexible. Elastic. They want it, but not *that* bad. And vice versa. | [
"is the analysis of consumer demand, as indexed by the amount of a commodity that is purchased. In economics, the degree to which price influences consumption is called \"the price elasticity of demand.\" Certain commodities are more elastic than others; for example, a change in price of certain foods may have a la... |
White reflects, black absorbs. White radiates little, black radiates a lot. What do transparent materials typically do? | Transparent materials let most of the light pass through. Also, many "transparent" objects are opaque to other wavelengths of light. Something that lets visible light through might for instance block radio waves or vice versa.
Also, white *reflects* visible light through diffuse scattering. Black absorbs visible light. How such objects irradiate is a separate concern and a function of temperature and their emissivity. | [
"Absorption of light is contrasted by transmission, reflection and diffusion, where the light is only redirected, causing objects to appear transparent, reflective or white respectively. A material is said to be black if most incoming light is absorbed equally in the material. Light (electromagnetic radiation in th... |
Do other mammals (or animals in general) "lose their voice" like we do? | **Disclaimer**: I wrote more than I meant to. If you don't want to read it all, the most important parts are the first and last paragraphs.
& #x200B;
Yes.... and no. The sounds made by all animals with lungs are made through vibrations in the larynx a.k.a. "voice box". In short, we (and other mammals) force air through our larynx while opening, closing, and vibrating it. Different shaped trachea, larynxes, and mouths result in the multitude of sounds created in the animal kingdom.
When we lose our voice it is usually because of a common cold, viral infection, or overuse of our voice box that results in swelling and irritation, in turn, inhibiting the use of our voice.
Since "losing our voice" is simply a result of interference with our larynxes, and every mammal as far as I'm aware of has a larynx; it is safe to assume that many animals can lose their voices.
The reason I said no at the beginning is because of this article.
[_URL_0_](_URL_0_)
It basically says that cats and dogs can lose their voices but while it is nothing to worry about when humans lose their voices, it can be very dangerous with some animals including cats and dogs. This is because it is much more common to lose their voice due to major things like trauma, cancer, paralysis, and sever infections.
In summary, many animals can lose their voice but many lose their voice for different reasons than humans do which is why we don't see it very often. | [
"Several non-human species demonstrate vocalizations that sound similar to human laughter. A significant proportion of these species are mammals, which suggests that the neurological functions occurred early in the process of mammalian evolution.\n",
"Most mammalian species produce sound by passing air from the l... |
why did chairman mao kill so many people including teachers? what could he have been trying to accomplish? | He was trying to purge China of The Four Olds as these were seen to only further the exploitation of the classes. The Four Olds are old customs, old habits, old culture, and old ideas.
A lot of teachers were executed publicly, monks were humiliated in the streets, a great number of Kung Fu masters took to the hills or left China altogether. These were all seen as part of the Old China that the Cultural Revolution was meant to be burning off. | [
"Benjamin Valentino noted that years after the conclusion of the campaign, Mao admitted that some people were \"unjustly killed,\" but insisted that \"\"basically there were no errors; that group of people should have been killed ... if they had not been killed the people would not have been able to raise their hea... |
Why are red and blue wavelengths of light most useful to photosynthesis? | Look [here](_URL_0_) Notice how on the left side of the total absorption graph everything is absorbed? If you are a plant, you don't want to be absorbing things in that region... so violet is less efficient than things to the right of it. | [
"Not all wavelengths of light can support photosynthesis. The photosynthetic action spectrum depends on the type of accessory pigments present. For example, in green plants, the action spectrum resembles the absorption spectrum for chlorophylls and carotenoids with absorption peaks in violet-blue and red light. In ... |
why can we still smell cigarette smoke i walk through when not breathing in? | The chemicals from cigarette smoke gets trapped in material (most likely fabric of some sort) and diffuses which is why you smell it. | [
"Sidestream tobacco smoke, or exhaled mainstream smoke, is particularly harmful. Because exhaled smoke exists at lower temperatures than inhaled smoke, chemical compounds undergo changes which can cause them to become more dangerous. As well, smoke undergoes changes as it ages, which causes the transformation of th... |
how do journalists find people? | Many people can be found through a phone book or a simple google search. Or you can call the company where you heard they work, or the school where you heard they study. Also, you can ask their current and former friends. | [
"A reporter is a type of journalist who researches, writes, and reports on information in order to present in sources, conduct interviews, engage in research, and make reports. The information-gathering part of a journalist's job is sometimes called \"reporting\", in contrast to the production part of the job such ... |
How thin (nanometer, atoms, etc..) can the human see, looking directly? | The visual resolution of the human eye is about 1 arc minute.
At a viewing distance of 20″, that translates to about 170 dpi (or pixels-per-inch / PPI), which equals a dot pitch of around 0.14 mm. LCD monitors today have a dot pitch of .18mm to .24mm.
Each persons vision is slightly different and some people have better vision then others. Experts believe on average that the naked eye — a normal eye with regular vision and unaided by any other tools — can see objects as small as about 0.1 millimeters. To put this in perspective, the tiniest things a human being can usually see with the naked eye are things like human hair (with the naked eye and under a microscope) and lice (with the naked eye and under a microscope).
Why is this the case? Lets do the math!
The finite size of the pupil sets upper limit on eye's resolution.
If the resolution of the eye is the smallest object the eye can see. This is limited by the diffraction limit, which is approximated by the formula,
DiffLim=~1.22x(L/D)
Where
DiffLim is the angular size of the object.
L is the wavelength of visible light.
D is the diameter of the pupil.
The angular size is just the ratio of the object's size versus the distance to the object.
The normal pupil size of a human eye is 4mm, which sets a minimum angular resolution of the eye at 2x10^{-4}rad. Obviously, we want to put small objects as close to our eyes as possible to be able to see them, but there is a minimum distance for comfortable viewing which is roughly at 25cm.
This works out to a size of 0.04mm if the human eye is diffraction-limited, but unfortunately, our eyes do not work at this higher limit. However, a quoted figure for the smallest resolvable size is 0.1mm, just double the figure estimated here, showing that the diffraction limit is a crucial factor in visual resolving power.
To double check.
Note that the separation of cones at the back of the human eye also effects visible resolution.
Light must hit separate cones for our brain to interpret them as coming from two different 'dots'. The diameter of the human eye is about 25mm and the separation of human cones is 2µm.
We can calculate the angular resolution (8x10^{-5}rad) and use the minimum comfortable viewing distance of 25cm to determine the smallest resolvable object, which comes out to be approximately 0.02mm. Close enough to the quoted literature value of 0.1mm.
Thus, the answer is ~0.1mm in thickness, any smaller and your eyes will have trouble differentiating the plane from the sky. | [
"Atomic dimensions are thousands of times smaller than the wavelengths of light (400–700 nm) so they cannot be viewed using an optical microscope. However, individual atoms can be observed using a scanning tunneling microscope. To visualize the minuteness of the atom, consider that a typical human hair is about 1 m... |
if gps satellites lose time due to the lesser effect of gravity, why can't we just adjust the clock speed to make up the difference? | We *also* have GPS satellites adjust their clock speed themselves. But there are a lot of variables, so it would take a lot of processing power to compute the adjustments exactly; it's much more efficient to just make them kinda accurate and resync regularly. | [
"The effect of gravitational frequency shift on the GPS due to general relativity is that a clock closer to a massive object will be slower than a clock farther away. Applied to the GPS, the receivers are much closer to Earth than the satellites, causing the GPS clocks to be faster by a factor of 5×10^(−10), or abo... |
What do historians think of Foucault's "Discipline and Punish"? | I'll start by re-posting here several segments I've previously posted on punishment and Foucault.
> His influence is hard to *overstate* ... he's frequently accused (and rightfully so) for his very selective historical sources, and for not doing sufficient archival work, but in general he remains an essential touchpoint for almost every historical work on punishment and incarceration [...] There are large caveats to these citations, which are often empirical objections, such as those pointed out by Spierenburg (*Spectacle of Suffering*, 1984). Elsewhere, it's true that many historians often cite Foucault's various writings without much further commentary, as if he's simply a necessary inclusion (and I'm certainly not alone in making this somewhat sad observation). [...] it should be made clear that you simply can't detach Foucault's theory from his historical works. He doesn't just use them as case studies for his thoughts; they were organic processes of writing, through which his practices and notions of archaeology and genealogy were developed. We have to be uncomfortably reductive to provide a synopsis of such a formidable theorist, but to phrase it simply, you have to understand that his histories were often long-scale, pulling back the historical strata—not solely in events but in what he called epistemes, or the epistemological boundaries of a culture’s discursive constructs of, say, the human body, of sex, of the purposes punishment, or of man itself—to explore the winding-through-history of such concepts. And you can really only imagine these by looking at them in practice: in Discipline and Punishment, he outlined the evolution of Western punitive thought from public punishment to incarceration as the individual subject replaced the communal, concomitant with the internalising process of panopticism ... (_URL_0_)
That's all a bit tangential, but perhaps might helps some understand a little where I'm coming from. I'm more interested in the punishments and violence of the penal system rather than the move towards incarceration, so what I'm saying won't perhaps apply to others; in other words, I view his work from the early modern perspective, which with *Discipline and Punish* is concerned in many ways only for the sake of argument ("pre-modern justice was less a serious object of study in itself [for Foucault] than an elegant theoretical foil to the logic of modern punishment", as Friedland, *Seeing Justice Done*, points out). But I think we have to pair him with other major theorists, in particular Norbert Elias, before anything truly productive is produced. For one, his claims of the early-modern executions' production of 'terror' for the public to reinforce sovereign authority ('Part 1: Torture' of *Discipline and Punish*) draw on Damiens' excruciating and drawn-out death - a very extraordinary case - to make more generalised arguments, which don't really hold up in ordinary acts of punishment (see e.g. Friedland, or Bastien, *L'exécution publique à Paris au XVIIIe siècle*, amongst many others, for varied challenges to this interpretation, including retribution, communal expiation, a return to deterrence and state consolidation, and so on). In this latter sense of its link to the state, secondly, you also need those like Elias to help link punishment to more concrete institutions and systems beyond Foucault's symbolic focus on sovereignty. Those like Spierenburg have therefore done amazing work to reinforce Foucault's thesis by combining it with Elias, while drawing analytical attention away from the former's almost too-blind emphasis on France, as well as underscoring how other forms of punitive spectacularity - and *not* executions and tortures - grew in strength in the 18th century (and furthered in more recent work by, as mentioned, Bastien, Friedland, Porret, Chavaud, etc.). As I wrote elsewhere:
> ... see Pieter Spierenburg's now-classic *The Spectacle of Suffering* for an overview on spectacular punishment. Although a little dated, it holds its place firm as a go-to in this historical field of public punishment in early modern to modern Europe, and deals with the decline in capital and other visual corporeal punishments, drawing on Foucault's seminal Discipline and Punish -- which charted the 18th- to 19th-century transition from the physical infliction of pain upon the criminal's body to judicial reforms increasingly preoccupied with rehabilitation via incarceration -- and Elias' state-centred Civilizing Process, with a few revisions. (His introduction has a good summary and criticisms on these two 'giants' of the topic.) On the pillory itself, there are too many to list, and it depends what your geographical interests are: John Beattie’s Crime and the Courts in England (1985) is frequently quoted for his descriptions of the pillory as the ‘paradigm’ of the era’s penal practice. A lot of other publications are journal articles behind paywalls, but if you do have access, see as just two examples McGowen, ‘From Pillory to Gallows: The Punishment of Forgery’ (1999) or Greene, ‘Public Secrets: Sodomy and the Pillory in the 18th Century’ (2003). (Those are completely arbitrary suggestions, by the way; there are many others, needless to say.)
To return to public penalties in general, there have been many possible answers proposed by historians and criminologists alike as to the causes of this growing antipathy to spectacular punishment. Squeamishness is one; others include the mounting control of the state, legal reformers' awareness of deterrence's failings, growing concerns for bodily integrity, and so forth. Some of these are problematic in their own respects. Shifts in elite sensibilities were not always concomitant with those of the lower classes when measured against continued popular attendance at executions during the 18th century, for instance. Others, like Foucault's narrative, have been found wanting; while discourses of pain and the body are important, for one, their dominance as causal factors might be reduced in favour of the sensibilities argument, since, as many have pointed out, hiding punishment did not necessitate its abolition. The death penalty is a notorious example of that, and I don't just mean in terms of the USA. (France's last guillotining was in 1977, for example.)
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"Foucault has frequently been criticized by historians for what they consider to be a lack of rigor in his analyses. For example, Hans-Ulrich Wehler harshly criticized Foucault in 1998. Wehler regards Foucault as a bad philosopher who wrongfully received a good response by the humanities and by social sciences. Acc... |
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