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how do lumens work? how much brighter is one 800 lumen bulb than two 400 lumen bulbs? | Lumens are like watts, but weighted to only include the light we can see; infrared and below is out, as is ultraviolet and above. So a bulb with twice as many lumens is twice as powerful, as far as we can see. The trick is that the human eye has roughly logarithmic sensitivity. If you saw a row of bulbs which were 100, 200, 400, 800 lumens, i.e., going up in brightness exponentially, you’d say their brightness was stepping up evenly. If you instead saw bulbs at 200, 400, 600, 800, you would think that there wasn’t much difference between the two brightest. | [
"The lumen is the photometric unit of light output. Although most consumers still think of light in terms of power consumed by the bulb, in the U.S. it has been a trade requirement for several decades that light bulb packaging give the output in lumens. The package of a 60 watt incandescent bulb indicates that it p... |
"ghost in the machine" | Ill give it a whirl since there are no answers yet. To a 5 year old I'd say the idea is basically like if you were eating alphabet soup. If you had enough "letters" you'd eventually get words then maybe sentences, and so on. Ghost in the machine is the same except deals with lines of code that cause unexpected/random behavior from a program. | [
"Ghost in the Machine is a children's horror/mystery novel by Patrick Carman, first published in 2009. It is the second book of the \"Skeleton Creek\" series, which is followed by three sequels: \"The Crossbones\" (2010), \"The Raven\" (2011), and \"The Phantom Room\" (2014). Like the other books in the series, it ... |
what happens after decapitation? | The point at which you cease to be "alive" and are "dead" isn't really clear-cut. However, brain function can exist as long as it has blood and oxygen, which it will for at least a few seconds. Even if you aren't dead, you are, at the very least, irreparable.
However, this crazy Russian scientist decapitated dogs and successfully kept them alive for a few hours by essentially [bathing them in blood](_URL_0_). Very graphic video. | [
"Decapitation is the complete separation of the head (caput) from the body. Such an injury is always fatal to humans and animals, since it deprives all other organs of the involuntary functions that are needed for the body to function, while the brain is deprived of oxygenated blood and blood pressure.\n",
"Less ... |
why is icing the injuries a good thing | Because inflammation can hurt. Icing causes blood vessels to restrict, prolonging the inflammation period that comes with an injury. As the area warms, blood will move in and inflammation will occur as normal, so the icing is for temporary pain relief. Obligatory I'm not a doctor, please feel free to correct. | [
"Injury Prevention: Athletic taping is recognized as one of the top preventative measures for reduction of injuries in collision sports. These injuries often occur as a result of extrinsic factors such as collision with other players or equipment. Athletic taping has also been shown to reduce the severity in injuri... |
why do a large number of companies prefer to pay their employees hourly instead of giving a salary? | Other posters have already covered the nefarious reasons for doing this so I'll add a legitimate reason for it.
The short version is "incentive alignment". If I want to convince people to spend more hours working it helps to pay them by the hour.
Some jobs are easily monitored for performance and it's easy to map that to time units. If I have a machine that needs someone to stamp 10 widgets per hour and I know that a person can stamp 5 widgets per hour, then hiring 2 hourly employees makes it really easy to map may expenses to output. If I need to adjust output I can relatively adjust my labor input to match.
If I put them on salary what do I do during times of heavy demand? Do I just ask the workers to put in more hours without changing their pay? Do I hire more workers and then pay them to sit around when I don't have work for them? None of those options are great but if I'm paying them hourly I can just pay them more to work more hours.
But some jobs are very hard to monitor and no one cares how much time it takes to do them, as long as it gets done on time. For example, if you make custom furniture I know that it's going to be hard to judge your work on an hourly basis since I can't easily differentiate between time that you spend thinking about how to modify the dimensions of my cabinet to fit into my house properly and time you spend just sitting around playing solitaire and billing me for it. So I'd rather pay you some fixed rate than an hourly rate. | [
"The reason that employees are often paid according to hours of work rather than by direct measurement of results is that it is often more efficient to use indirect systems of controlling the quantity and quality of effort, due to a variety of informational and other issues (e.g., turnover costs, which determine th... |
how do large cities not run out of number and letters combinations to put on license plates? what would happen if they did? | Because with a 7 digit license plate, there are over 78 billion unique combinations of letters and numbers. If any licensing agency somehow managed to exhaust that number, they would just add another digit. | [
"There was no standard for the registration numbers at that time. Every city had its own plate format and color, and the background color for the plates could vary from year to year in a single city. The plates were required to contain a numbers-only registration number and optionally the name of the city, the year... |
Why did the Curiosity Rover travel 100 million extra kilometers on its way to Mars? | It has to do with the fact that *Curiosity* didn't travel in a straight line. Mars moved from where it was when *Curiosity* left Earth, and was in a completely different location by the time the Rover got to it. *Curiosity*'s path was a long curve because of this, not a straight line. | [
"The Mars rover \"Curiosity\" is a mobile laboratory that was launched from Cape Canaveral in 2011. The Curiosity landed on Mars surface August 6, 2012. This was the largest rover NASA has put on Mars, being twice as long and five times as heavy as its processors. Despite the extra size the Curiosity took many desi... |
Can anyone tell me more about this birth control political cartoon? | You may want to contact this university. You can see on the left side of the image they have it on display.
_URL_0_ | [
"Commentators point out that political cartoon draws directly upon \"The Problem We All Live With\" by Norman Rockwell, which depicts Ruby Bridges being escorted to school as a child during a time when crowds of white protestors would actively prevent desegregation efforts initiated by the \"Brown v. Board of Educa... |
How is it the French were able to conquer Vietnam and keep it as a colonial holding for so long? | France conquered Vietnam in 1885 mostly by virtue of superior military technology and a fairly ineffective Vietnamese monarchy. The emperor at the time (Tu Duc) did not understand the danger that the French posed, and the Vietnamese military was horribly outmatched. France had steamships, machine guns and modern artillery. Vietnam had spears and cannons that fired stone balls. Further, Tu Duc eventually gave up fighting, hoping that cooperating with the French might preserve some measure of independence for Vietnam. That did not happen.
An anti colonial uprising broke out almost immediately after France seized Vietnam. It was called *Can Vuong*, or "Restore the King," and was mostly located in Northern Vietnam. As the name indicates, *Can Vuong* tried to kick out the French and restore the monarchy to prominence. The French were able to crush this movement by 1889. Thereafter they ruled with an iron fist.
It's true that France never had many troops in Vietnam. They maintained control in a few ways. First, they split Vietnam into three parts - the north was called Tonkin, the center Annam, and the south Cochinchina. They scrubbed all mention of Vietnam as an independent nation from the educational system. Vietnamese people were no longer to consider themselves Vietnamese. Rather, they were Tonkinese, Annamese or Cochinchinese. France portrayed itself as essential to Vietnam's development - France was the mother country. They also did their best to coopt the Vietnamese upper class, who were mostly intellectuals and regional politicians known as mandarins. Despite this effort, some Vietnamese intellectuals spoke out against French colonialism. Probably the most famous was Phan Boi Chau, who wrote a book called *Viet Nam Vong Quoc Su* or History of the Loss of Vietnam, in the early 1900s. This book laid out that Vietnam had once been independent and also that France had conquered it. Needless to say, the French considered this book very dangerous, and Phan Boi Chau spent much of his life either on the run or under house arrest.
France also maintained control through extremely high taxes and the corvee system. Peasants had to borrow money from French officials to pay their taxes, which meant that they were caught in a never ending cycle of debt. Under the corvee system, most peasants were required to spend a certain amount of time (say a few months) as unpaid laborers. And France also used native levies and informers, much like the British in India. Until the Viet Minh, all uprisings were easily localized and isolated. What made the Viet Minh special was their ability to build a national network across all of Vietnam, making it very difficult for the French to stamp them out. | [
"Vietnam was a French colony from 1858, until the Japanese \"coup d'état\" in 1945. By 1897, the French had created the Federation of Indochina, with Vietnam divided for convenience into the separately ruled territories of Tonkin, Annam, and Cochin China, plus newly acquired Cambodia and Laos. To justify their impe... |
how did artwork like the mona lisa, the last supper or the statue of david become so much more famous and well known than other lesser known impressive art? | I'm not familiar with the Last Supper and Statue of David's history, but I do know that the Mona Lisa was stolen right out of the Louvre, and later recovered, which contributed significantly to it's presence in the public's eye. | [
"Leonardo da Vinci's \"Mona Lisa\" is one of the most recognizable and famous works of art in the world, and also one of the most replicated and reinterpreted. \"Mona Lisa\" replicas were already being painted during Leonardo's lifetime by his own students and contemporaries. Some are claimed to be the work of Leon... |
why is it so cheap to buy items in america vs other areas of the world | It *totally* depends on where you live in the US.
**Housing Prices**--go to San Francisco or NYC, and you'll see a moderate home costing more than $500,000 USD. Go to Nebraska, you'll see a home for less than $100,000.
Part of it is geography. New York and other metro areas (San Francisco, Boston) are constrained. Manhattan is an island, so there is a definite limit to new housing. In the northeast (New York, Massachusetts, the rest of New England) there is literally *no* unincorporated land. Every town borders another town, so finding new space to build houses often means building *vertically*. In the Mid-West, there's a lot of flat open land, a lot of *unincorporated* land, and not a lot of people, creating "suburban sprawl" as new houses get built. (Can't find a house you like? Go a 1/2 mile outside of town and build a new one!)
**Groceries**--Again, depends on where you live. A *lot* of land in the Mid-West is farm land, and then a lot of land in California is farmland. The closer you are to where your food is grown, the cheaper (and fresher) it is. Ask an Alaskan or Hawaiian, and they'll tell you about $9/gal milk and other ridiculous prices, because food needs to travel so far. The US tends to have a lot of farm subsidies as well, which keeps food prices pretty low (because farmers can and do overgrow).
**Living Expenses**--Things like gasoline are way more expensive in places like Europe. Part of that is the fact that we have some domestic oil, part of that is the fact that we don't tax our oil/gas very much. Other random products that are produced in the US are sold to you more expensively because they're imports, and have to travel pretty far to get to you. | [
"Inexpensive foods like instant noodles, bologna, pizza, hamburger, mass-market beer, frozen dinners, and canned goods are additional examples of inferior goods. As incomes rise, one tends to purchase more expensive, appealing or nutritious foods. Likewise, goods and services used by poor people for which richer pe... |
why is it bad for the government to have access to internet data? | Government agencies that start out with the best intentions, can be politically co-opted over time to have not-so-good intentions. Furthermore, individuals with access to data can easily use that data for nefarious purposes (how about blackmailing Phil?) And politically speaking it's incredibly hard, once you give access, to take it away.
| [
"The government controls domestic Internet servers and sporadically monitors Internet usage, but by the end of 2012 it apparently did not have the ability to block access to Web sites. Authorities have developed infrastructure to route all Internet traffic through a single gateway, enabling them to monitor and rest... |
Did Hitler kill Atheists amd Agonstics as well? | Hi there, your question suggests few misconceptions about the reasons behind the persecution of Jewish people by the Nazis. There is always more to be said, but I think you will definitely find [this fantastic answer](_URL_0_) by /u/commiespaceinvader interesting and enlightening. | [
"During his career, and for a variety of reasons, Hitler made various comments against \"atheistic\" movements. He associated atheism with Bolshevism, Communism, and \"Jewish materialism\". Overy writes of Hitler as skeptical of all religious belief, though not a thorough atheist:\n",
"According to Bullock, as an... |
how long does brain matter survive without perfect conditions? | The concentration of ions around a neuron is very important for it's survival. One way the ionic balance is regulated is through blood supply. A scattered brain will likely have inadequate blood supply, leading to neuronal impairment and death. | [
"Some rare organisms, such as tardigrades, usually have short lifespans, but are able to survive for thousands of years — and, perhaps, indefinitely — if they enter into the state of cryptobiosis, whereby their metabolism is reversibly suspended. It is hypothesized by advocates of cryonics that the human central ne... |
hedge funds, venture capitals, and futures trading. | Venture capital is money from small groups of investors or individuals who are willing to invest in private companies.
Hedge funds are investment funds that theoretically invest to do well if the general market does not. In practice, they are investment funds that are able to do exotic or high risk things in exchange for limiting investment to only wealthy people who are expected to understand the high risk of the investment.
Futures trading is betting on the future market values of commodities. It is based on being able to make contracts dated in the future. If I grow corn, I can agree to sell my corn that will be harvested in 6 months at a price today. If the market price goes down, I get more. If the market price goes up, I don't get the extra. People who don't grow of need corn can also make these deals, but need to get out of them before the corn must be delivered. | [
"The hedge fund invests in public equity, fixed income, currency, and commodity markets across the globe, as well as in derivatives including spot currencies, futures contracts, forward contracts, swaps, and options. From its inception in 1993 through May 2009, it had annualized returns of approximately 12%, over t... |
What were the major flaws of the Soviet invasion during the Winter War. | The winter war isn't quite my area of expertise, it's kind of adjacent though, so I'll heavily lean on journal articles and books for this.
> Soviet forces performed dismally in the initial offensive operations during that war. Offensive preparations were poor, coordination of forces weak, and command and control ineffective. Consequently the first offensive failure was a major embarrassment. Only after more extensive mobilization and intensive preparations was the Finnish defense crushed.
David M. Glantz, *Soviet Military Operational Art* p. 91
> On 30 November 1939, 9th Army formations (54th, 122nd, and 163rd Rifle Divisions^4 ) crushed the Finnish border outposts and advanced swiftly. The Finnish command was able to concentrate 5-6 battalions with a few mortars and artillery against them. In view of the Soviet forces' significant superiority, the Finns waged only containment battles at earlier prepared positions, and gradually withdrew into the depths of their territory. **During these battles they stopped the pursuing Red Army formations for several hours, and then continued to withdraw, destroying bridges and constructing barriers on roads.**
> General I. Siilasvuiu, 9th Infantry Division commander, recalled, 'It was strange and incomprehensible to me why the Russians had no skis and, therefore, could not leave the roads. They suffered heavy losses because of this.'^10 **In fact, the lack of skis and the inability to ski on the part of personnel not only from 163rd Rifle Division, but also from all other Soviet divisions (except for 54th Mountain-Rifle Division) resulted in the fact that the regiments were able to move only along roads, and the deep snow made it impossible for units to move off the roads or maneuver in any way.** This greatly contributed to the success of the mobile Finnish ski detachments: it made it possible to make unexpected attacks from the flank and into the rear of Soviet units, and to easily avoid pursuit in case of failure.
Emphasis added. The Finns fought a dogged defense in depth, and the Soviets had persistent C2 and organizational issues, as well as mobility issues, which the Finns exploited. This, I think, is part of why they held on for so long. The Soviets were unable to exploit their armored advantage, as the terrain in the region is rather hard to move in. Telling is the report written by Maj. S. G. Chernov, quoted in Aptekar and Dudrova "The Unheeded Warning and the Winter War" *Journal of Slavic Military Studies* V. 10 No.1 (March 1997) P. 207
> The role of 9th Army and its missions are understood correctly by the army command, but the decision is built on the fact that the enemy will not offer resistance... **The operational tempo was planned for an average of 22 km per day, at a time when our forces were moving 12-16 kilometers per day toward the border, with units being spread out and equipment (mainly artillery) lagging behind. How, then, can such a tempo be planned for enemy territory?!** This means to build an operation on sand, without a real condition or front features. In the calculations, the enemy was not taken into account, nor was the lack of roads considered, this is a gross operational miscalculation, and later this may be at the cost of thwarting the entire operation at the very beginning, especially if the enemy offers resistance by means of obstacles and covering them with border units, not to mention bringing up field forces... All their lines of communication will be cut by enemy diversionary groups, and they will be without food or ammunition; Finnish tactics will basically boil down to this... It is necessary now to create in divisions detachments of good skiers and to concern ourselves with providing skis to all divisions. It will be very bad without skis, they will not be able to leave the road, but will meet the enemy (head to head) and this will delay movement very much.
Emphasis added. Chernov mentioned in the margins,
> This haste may end badly, the operation has not been thought out, I don't know about the other armies, but this may be thwarted, especially with respect to 9th and 8th Armies.
Let's now draw our attention to excerpts from the curricula of the Voroshilov General Staff Academy 1977 history textbook, to get a view of why the Soviets thought they lost the war. David M. Glantz, "Excerpts on Soviet 1938–40 operations from the history of warfare, military art, and military science, a 1977 textbook of the military academy of the general staff of the USSR armed forces" *Journal of Slavic Military Studies* Vol. 6 No.1, March 1993,
> At 0830 on 30 November Leningrad Military District forces crossed the Finnish border. Thus began military actions between Finland and the USSR. Although ordering its forces to attack, the Soviet government had no intentions of seizing Finland and depriving it of independence. Rather, it strove only to put an end to using this country as a bridgehead for anti-Soviet forces. (p. 122)
> ***
> Since ancient times Finland has been renowned as the 'country of forests and thousands of lakes.' There are more than 30,000 lakes in Finland, and they occupy 12 per cent of its entire territory. Forest tracts encompass 74 per cent of the country's entire area. If to this are added numerous rivers and very rugged terrain covered by deep snow, rocky ridges, cliffs, and enormous boulders, then it is easy to imagine how natural conditions have made Finland inaccessible to invasion from the east. The terrain was so advantageous for defense that even its insignificant reinforcement with field fortifications provided an enormous advantage to defending forces. Natural conditions seriously impeded movement and maneuver of large formations, and created extreme difficulties for the attacker. Red Army forces had to fight under conditions of a cruel winter, in deep snow, with no roads, often in dense fog, under conditions where it was impossible to employ modern combat equipment and weapons with adequate effectiveness (p.123)
> ***
> At 0830 on 30 November 1939, following a 30-minute artillery preparation on the Karelian Isthmus and a 15-minute artillery preparation on the remaining axes, Soviet forces crossed the Finnish border. For several reasons the Soviet-Finnish conflict did not progress in full accordance with the Soviet command's plans and recommendations. (129)
Possibly the understatement of the century there. Like damn.
> Limited results and the incompleteness of planned Soviet operations can be explained by the fact that they were not prepared beforehand for actions to penetrate fortified regions. Our military theory had not adequately worked out forms of combat actions under special conditions. Thus, in Provisional Field Regulations-36, only one article (212) was devoted to the offensive against a fortified region; this stated: 'The offensive against fortified regions or sectors is conducted on the basis of special instructions.' However, such instructions had not been developed.
> In the plan for Field Regulations-39, nine articles were allocated to the question of penetrating fortified regions, but they did not receive adequate clarification. The situation was analogous with the problem of an offensive in a forest and forested-swampy terrain covered with lakes, as well as in the inter-lake defiles, under severe winter conditions.
> ***
> The experience of combat actions against Finland in 1939-1940 had enormous significance for the development of Soviet military art. On this basis the Soviet Army began to create its theory of penetration of a fortified region
> Combat actions in the Northwestern Theater demonstrated the Soviet command's ability to concentrate overwhelming forces and means on a selected principal strategic axis (Karelian Isthmus) and subordinate the actions of all armed forces services to the primary mission - the rout and destruction of the main enemy grouping
> The penetration of the Mannerheim Line using all modern combat means was a unique phenomenon. This was the first experience in the world of such a front operation. Dynamic actions of Soviet forces on other operational axes on the enormous Soviet-Finnish front were closely coordinated with its concluding stage.
> It was established that it was expedient to penetrate a reinforced defense in a narrow front sector with a deep force combat formation by successively capturing separate defensive objectives with powerful means of destruction and suppression; a plan worked out in detail and especially careful preparation were necessary. Practical combat experience in Karelia confirmed the correctness of methods of artillery support of the troop offensive, which consisted of artillery preparation, support of the attack, and accompaniment. The most effective method of attack support was an artillery fire barrage, sometimes in combination with successive fire concentrations. Combat experience in Finland was _URL_0_ the new draft Field Regulations 1940, and in a number of instructions and manuals on troop combat preparation. It was the subject of intensive study and generalization at the 1940 March Plenum of the Party Central Committee, and at a meeting of the Main Military Council in April 1940. Troop combat readiness was increased on the basis of decisions made by them, and combat training approached actual war conditions
****
So, in summation, what were the Soviet flaws? Limited mobility, persistent command and control issues, and fighting in terrible conditions which heavily favored the defender. Even still the Soviets were able to achieve their aims and then some by peace treaty. Given the actions of the Finns during '41 in the march on Leningrad the border movements as a result of the Winter War shouldn't be underestimated.
****
Hopefully this is a somewhat complete answer to your question! I'm running up against the character limit, but feel free to ask follow-ups! | [
"Operation Winter Storm (\"Unternehmen Wintergewitter\"), undertaken between 12–23 December 1942, was the German Fourth Panzer Army's attempt to relieve encircled Axis forces during the Battle of Stalingrad. In late November, the Red Army completed Operation Uranus, which resulted in the encirclement of Axis person... |
what is big o, big omega, and big theta notation? | When you have two sequences or functions, you are often interested in how fast they grow compared to one another. For example, suppose you have two functions f(n) and g(n) that tell you how many operations two different algorithms use to sort a list with n elements. As n gets bigger, if the number of operations f(n) gets bigger faster than the number of operations g(n) gets bigger, then you would say that g(n) is a more efficient algorithm. There are a variety of ways to make that idea more precise, and Big O/Omega/Theta are one of them.
"f(n) is Big O of g(n)" means that the rate of growth of f(n) is at most the rate of growth of g(n).
"f(n) is Big Omega of g(n)" means the rate of growth of f(n) is at least the rate of growth of g(n).
"f(n) is Big Theta of g(n)" means f(n) and g(n) have the same rate of growth. | [
"Omega (capital: Ω, lowercase: ω; Greek ὦ, later ὦ μέγα, Modern Greek ωμέγα) is the 24th and last letter of the Greek alphabet. In the Greek numeric system/Isopsephy (Gematria), it has a value of 800. The word literally means \"great O\" (\"ō mega\", mega meaning \"great\"), as opposed to omicron, which means \"lit... |
How do fish and other forms of aquatic life find their way into man-made bodies of water? | This one is a big FAQ, so I'm going to link you to the best answer we have on this:
_URL_0_ | [
"Fish live in Fresh or Saltwater habitats and some exceptions are capable of coming on land (Mudskippers). Most fish have a line of muscle blocks, called myomeres, along each side of the body. To swim, they alternately contract one side and relax the other side in a progression which goes from the head to the tail.... |
What is the difference between a quark and an antiquark? Do they both collide and destroy each-other like antimatter and matter? | > What is the difference between a quark and an antiquark?
Quarks are a type of particle which comes in 6 flavors, and those 6 flavors each have a corresponding anti-particle making 12 unique types of quarks. The quarks and their anti-quarks have opposite charge and parity.
> Do they both collide and destroy each-other like antimatter and matter?
They form mesons which can decay in a number of ways, just like matter-antimatter. If the net charge is zero, it can annihilate into photons. | [
"The quarks are bound together by the strong force, which acts in such a way as to cancel the colour charges within the particle. In a meson, this means a quark is partnered with an antiquark with an opposite colour charge – blue and antiblue, for example – while in a baryon, the three quarks have between them all ... |
the first time you smoke weed it has little effects. why? | Ok, I'll go for it: the first time I smoked weed was when I was 17 years old. My buddies and I went to a local park and made a gravity bong (this plastic water bottle device that filtered smoke) very rudimentary. I had to bring a knife from my house to cut the bottle. Anyway, we all do it again and again until we hear a siren. 95% of the group gorilla panics and jets hella quickly. I feel nothing, and figure it's not for us.
Despite the pull if herd panic, one dear friend summons the courage to remain. Let's call him E. We have a small pipe and a lighter and we really hit it. The wind was gusting so hard we had to stand in a corner facing the wall. He asks, "are you feeling it?" I don't answer; I'm too busy looking over his shoulder at the one light streaming though window. It's sharp contrast to the dark evening and the light draws my interest.
"Yeah, you're feeling it."
We call our buddies and find they're at an adjacent fast food place. We walk over through the orangle light of the park. I couldn't prevent it even if I tried. It exploded out of me with the eruption of 6 million asteroids striking a planet at once! "Dude! I feel like we're in a Clockwork Orange!" I laughed hella hard. We ran. It was fun. Went to the fast food joint, felt like I could taste the chemicals in the chicken. Still a great time. Just inhale really deeply | [
"The cause is unknown, but it is thought to be caused by intracellular edema of the superficial epithelial cells coupled with retention of superficial parakeratin. Although leukoedema is thought to be a developmental condition, it may be more common and more pronounced in smokers, and becomes less noticeable when s... |
Why is it so hard to perceive what the world would look like with additional eyes on the back of our head? | The mental image we 'see' in our minds isn't a direct representation of reality. It is a huge mess of signals arriving from billions of neurons connecting the cells on your retina with your visual cortex. On its own it does not constitute an image. The image we see is solely down to having experienced these signals for the duration of our lifetime. As our brains developed we began associating certain kinds of signal with certain forms of external stimuli. It is only because we've gone through this developmental process that we do have a mental image.
Therefore it is impossible to imagine what it would be like to have any other eye arrangement than your own, because what you see in your mind is a direct result of the eyes you have.
Another reason that it makes it hard for humans specifically is that we use both our eyes to focus on one object. We can't look at two separate things independently. If you had eyes on the back of your head, it would be impossible to use all 4 to focus on the same thing, so your mental image would have 2 focal points. | [
"\"The eyes do not focus on any outward object, and they give the impression that they will remain where they are: they see through the filter of an inner state, rather than receive immediate impressions from the outside world. It is the attitude of being suspended in a state of mind beyond specific thoughtunaware,... |
how is graphene battery better than lithium-ion battery? | Several ways. First off is the material it's made from. Graphene is the name for a particular structure of carbon atoms. Carbon is plentiful here on Earth. In fact, we've got too much of it in the atmosphere. Lithium, on the other hand, is a comparatively rare metal, which must be mined and refined through processes that can have devastating effect on the immediate area.
Second is the charge time. Graphene batteries charge 5 times faster than Li-ion. With more and more Electric vehicles and hybrids hitting the roads, charge time is one of the biggest barriers to their widespread use. If you could cut the rapid charger charge time from 1 hour down to 12 minutes, you're starting to approach gas station stop times.
Third is energy density. Lithium based batteries generally have an energy density of around 180 Watt-hours/Kg (For each kilogram of weight, the battery can sustain 180 Watts of draw for an hour). Graphene batteries run around 1000 Wh/Kg, and the Tesla Model S battery boasts an energy density of 2000 Wh/Kg. | [
"The use of graphite in batteries has increased in the last 30 years. Natural and synthetic graphite are used to construct electrodes in major battery technologies. The lithium-ion battery utilizes roughly twice the amount of graphite as lithium carbonate.\n",
"Graphene could be used to improve the electrical con... |
why is poverty level related to diabetes risk? | Type 2 diabetes has a lifestyle attribute to it. That means that in many cases (not all) a person's lifestyle can have an effect on their chances of developing the disease.
When you consume large amounts of carbohydrates (sugar, starch, breads, stuff like that) it puts pressure on your pancreas to produce insulin. You also start to develop **insulin resistance**. You are still making insulin (other types of diabetes like type 1 cannot make insulin) but that insulin isn't as effective. Therefore you need to make more and more. This basically tires the pancreas out and you develop type 2 diabetes.
So how does that relate to poverty? Carbs are cheap. Cheaper and more processed foods are going to, on average, contain more carbs. If someone is struggling with money, they may choose to buy something that is higher carb but cheaper. Overtime this can cause the insulin resistance described above. | [
"The Centers of Disease Control and Prevention (CDC) released a report in 2015 indicating that more than 100 million Americans have diabetes or pre-diabetes. Diabetes was the seventh leading cause of death in United States in 2015. In developed countries like the United States, the risk for diabetes is seen in peop... |
Is there any functional difference at either the hardware or software level between selecting 'restart' to restart your computer, or pressing shut down, and turning it back on? | At the OS level, no. The operating system will completely shut itself down either way. Likewise, all the hardware in your system *should* have its state cleared during the restart. A reset signal is sent by the motherboard to all of the components in the computer on the restart. However, everything inside the computer remains powered on (hard drives, video card, and all of the various peripheral controllers, like the USB controller), unlike in the case of a shutdown, which kills power to (almost all\*) the components. If those systems don't respect or improperly implement a reset procedure, the computer may not be returned to the same state as it would after a true power off/on.
I've actually experienced this problem in person. I had a PCI-E fiber interface card (which interfaced with a scientific system) that failed to properly reset during a soft restart. Wasted a good amount of time till I figured that out, because a restart and power off *should* behave the same.
\*For an example of one that isn't, a lot of modern systems will keep power to the USB devices so you can charge phones off the USB ports even with the computer off. | [
"BULLET::::- \"Restart Manager\": The \"Restart Manager\" works with Microsoft's update tools and websites to detect processes that have files in use and to gracefully stop and restart services to reduce the number of reboots required after applying updates as far as possible for higher levels of the software stack... |
why was american pharoah slower than the previous triple crown winner? | The consensus seems to be that Secretariat (in the 70s) was a genuine freak of nature. You'll notice that most of this year's horses finished faster than most of that year's horses, so on the whole the entire sport has gotten faster and more competitive. But Secretariat was a statistical anomaly. | [
"American Pharoah won the 2015 race, becoming the 12th horse in history to win the Triple Crown and the first in 37 years. The crowd that year was limited for the first time, to 90,000. His time of 2:26.65 was the sixth-fastest in Belmont Stakes history, and the second-fastest time for a Triple Crown winner. In 201... |
how do bones heal when they break, and what's the difference between being young or old? | Your bones are alive.
When your bones aren't broken, you normally have cells called Osteoclasts breaking down the parts of your bones that are worn out, and Osteoblasts rebuilding them.
Even an Adult will typically replace 10% of their skeleton every year.
When you break a bone, it breaks blood vessels in and around the bone.
This causes swelling and is the first structure for rebuilding.
Your Osteoblasts then get to work.
First they'll lay down a soft structure, mainly made out of collagen (same stuff that makes up alot of hair, skin, muscle and other soft structures in your body).
Then they'll later add in calcium, which makes the bones hard.
This happens faster for children, but then again almost everything related to cell function happens faster for children.
| [
"Bone fracture, which is a complete or partial break in the bone, is a very common condition that has more than three million US cases per year. Human bones have the ability to regenerate themselves by cycle of bone resorption and bone formation. The cell responsible for bone resorption is osteoclast, while the cel... |
Any good biographies on famous ancient Roman Greek hero's/warriors? | **5 Greek Warrior-Generals Whose Biographies Will Make You Feel Like a Massive Underachiever**
We all know the great heroes of Greek epic - the wily Odysseus, the invincible Achilles, the unrivalled Diomedes who cut a swathe through the Trojans and defeated multiple actual gods in single combat. But what about the heroes of history? It turns out all the little Greeks who grew up reading Homer thought of it as more than a kick-ass bedtime story. They saw a benchmark of badassery. Then they grew up and lived up to it.
Here are some Greek warriors you won't read about in mythology - *but you should.*
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**1. Pelopidas ain't afraid of no Spartans**
It's a hard life growing up in a world where Spartans call the shots. Especially if you're from Thebes and the Spartans straight up overthrow your government, put a garrison on your acropolis, and strut around like they own the place. Most Thebans might have thought that these grim-faced sourtherners were a bit much to handle, but Pelopidas wasn't impressed.
To get rid of the Theban oligarchs who acted as the Spartan puppet government, he got together his hottest friends, dressed them all up like girls, and crashed the oligarchs' drinking party when they were too drunk to tell a jacked young badass from a sexy lady. The oligarchs were delighted to see that the evening's entertainment had arrived. They were less delighted when Pelopidas and his sultry pals cast off their dresses and stabbed them all to death.
So Thebes was liberated. But the Spartans were *pissed*, and they weren't going to stand for this shit. Thebes needed soldiers. So Pelopidas formed the most badass hoplite unit ever to grace the battlefields of Classical Greece: the Theban Sacred Band.
Here's where the badass meter hits the red. In 375 BC, Pelopidas and his Sacred Band were marching around guarding the countryside when he was told there was a force of Spartans up ahead that outnumbered him 4 to 1. Being outnumbered 4 to 1 by literal Spartans would be enough to make any lesser general crap his *himation*. Pelopidas, though? When his men told him in despair, "We've fallen into our enemies' hands!" did he throw up his hands and surrender? Of course not. He replied, "Why any more than they have fallen into ours?" Then he attacked. Then he broke and routed a Spartan army 4 times as large as his own.
Pelopidas' reckless bravery became the stuff of legend. When Plutarch wrote [his biography](_URL_6_) centuries later, the main message he wanted to impart on his readers was "be badass, but don't try to be as badass as Pelopidas, *because you'll die.*" Important lessons from history.
& nbsp;
**2. Timoleon is here to play bingo and kick ass**
Timoleon was just minding his own business as a regular citizen of Corinth when all of a sudden, his brother decided to try and seize the government. Did he back his own kin, for the sake of blood and loyalty? Of course not. He took up arms for his city and personally killed his brother in battle.
Because of this act of stone-faced championry, Timoleon was something of a local hero. So when the people of Syracuse called upon their mother city of Corinth to help them overthrow the tyrants who were oppressing Sicily, they were overjoyed to hear that Corinth would send Timoleon. There were just 2 tiny problems. First, Timoleon was already pushing 80, and couldn't see so well anymore. Second, the Corinthians sent him over with just 1200 men. Really, they were giving token aid to the people of Sicily, and the Syracusans had every right to be pretty annoyed at Corinth' lack of commitment.
Until Timoleon started to do his thing.
Not at all deterred by the fact that he was a decrepit senior citizen with failing eyesight and a sad excuse for an army, Timoleon marched around Sicily deposing one tyrant after another, eschewing no trick or device to crush them and to restore democracies everywhere. Then the Carthaginians invaded with a massive army, and Timoleon went and crushed them, too.
After this, the Syracusans accepted that Timoleon could basically do no wrong. Plutarch's [biography](_URL_4_) tells us that when he eventually went fully blind, they continued to consult him on all their public matters until the day he died. Also, from then on, whenever they had a problem they couldn't handle, they knew what to do: send to Corinth for help.
& nbsp;
**3. Alexander the Great is exactly what it says on the tin**
Is there any need to recount what makes Alexander earn his title? Where do we begin? Well, we could point out that he personally destroyed the Theban Sacred Band in battle when he wasn't even old enough to buy beer. We could also point out that he overthrew the most powerful empire that the world had ever seen, in about as much time as it took for him to walk from one end to the other. We could stress that he did all this while leading his armies from the front and repeatedly getting himself almost killed by enemy swords, spears, arrows, and catapult bolts, sustaining himself on pure visceral death-seeking bloodlust. He ragequit life in his mid-30s, probably because he'd gotten bored of the Ancient scenario and wanted to play a different level.
You can read Plutarch's version of his life [here](_URL_2_); there are also surviving biographies by Arrian and Curtius Rufus, who all cite many others, because the next best thing to living Alexander's life was apparently describing it in awestruck wonder.
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**4. Agesilaos is short and lame and still beats up everyone**
Being king of Sparta comes with a few expectations. Agesilaos, to be fair, never thought he would be king of Sparta, and went through the ruthless Spartan education like a regular citizen. But then shenanigans happened and bam! The crippled little kid brother became king. And did Agesilaos spend his time nursing his lame leg and enjoying the fruits of kingship? Hell no. He went out and kicked ass from Akarnarnia to Egypt, leading armies against Greeks and Persians and anyone else who stared at his leg funny, remaining entirely undefeated in battle until he died at age 84 from carrying too much loot back to Sparta.
He went to Asia to fight the Persians, and defeated the Persians, "liberating" a great deal of money and a herd of camels. He went to Thessaly and defeated the Thessalians, pitting his cavalry against the finest horsemen of Greece and winning. He went to Boiotia and defeated the Boiotians, taking the Thebans head-on while in the front rank of his phalanx, and igoring his wounds until the enemy was completely broken. He spent decades marching all over Greece and wiping the floor with anyone who dared to face him. And when Sparta needed money, Agesilaos went to Egypt to fight the Persians and the local rebels there, and beat them too.
Meanwhile, in the rare moments when he was at home, he defused two separate uprisings in Sparta, and backed his sister, who ended up being the first woman ever to win the Olympic chariot race. Because why would you be badass in just one way, if you can be a disabled old omni-badass?
We know a lot about Agesilaos because his friend Xenophon [wrote his eulogy](_URL_1_.). Plutarch, not to be outdone, [wrote another one](_URL_3_).
& nbsp;
**5. Iphikrates is the memetic badass of Antiquity**
At the start of his career, Iphikrates was just a regular dude serving as a deck-fighter in the Athenian fleet. Like any regular dude, during the battle of Knidos in 394 BC (probably), when he fell wounded, he dragged his enemy overboard and hauled him over to his own ship, while both of them were wearing full armour.
Actually, wait, that's not like any regular dude, that's monumentally badass.
When we read about antiquity, we might hear about great commanders like Perikles, Epameinondas and Alexander. But when Polyainos compiled his book of military stratagems to present to the Roman Emperor Marcus Aurelius, there was no doubt in his mind as to which should be the most prominent: Iphikrates son of Timotheos. While people like Alexander get only a handful of stratagems to their name, and many generals get just 1 or 2, Iphikrates' chapter has a whopping *sixty-one* entries - nearly 3 times as many as the second place (which is, of course, Agesilaos). Iphikrates was just that good.
He once obliterated an entire Spartan army without losing a single man, which persuaded the Athenians that he was pretty good as a general. From then on, until the end of his life, whenever things got particularly sticky at Athens, they called on Iphikrates to sort their shit out. Plutarch tells us that his enemies learned to get the hell out when they heard his name. Even his own people were scared shitless of Iphikrates; one time when they dared to put him on trial for treason, he persuaded them to let him off by simply walking into the courtroom and showing the jury a knife.
Allegedly he was once negotiating with Iason of Pherai on a neutral barge in the middle of a river when he figured out that Iason was trying to fleece him. As Iason was watching his priest prepare to sacrifice a bull to ratify the treaty, Iphikrates got out of the boat, climbed up on the nearby bridge unseen, then jumped down suddenly onto the barge, snatched the knife from the hand of the priest, and held it against Iason's throat. Negotiation, Iphikrates style.
There are endless stories cementing Iphikrates' relentless badassery. Nepos wrote a short [biography](_URL_0_) and Plutarch gathered some choice [quotes](_URL_5_). | [
"The Romans did not generally attempt to compete with free-standing Greek works of heroic exploits from history or mythology, but from early on produced historical works in relief, culminating in the great Roman triumphal columns with continuous narrative reliefs winding around them, of which those commemorating Tr... |
What are the most plausible cosmological models which rule out a "beginning point" like the big bang? | It's funny that you mention you're an atheist to convince people it's not Christian skepticism in the Big Bang - the Big Bang model really took off with LeMaitre, a Catholic priest, and was very well supported by Christians, including the Pope. After all, it's evidence that the Universe began in a creation event.
Anyway, there really isn't any non standard infinite age Cosmology that is supported at all . There are a few well respected physicists who still believe in them (Jayvant Narlikar notable) but, really there aren't any plausible models that even come close to standard Big Bang cosmology. | [
"The Big Bang model, or theory, is now the prevailing cosmological theory of the early development of the universe and was first proposed by Belgian priest Georges Lemaître, astronomer and professor of physics at the Catholic University of Leuven, with a PhD from MIT. Lemaître was a pioneer in applying Albert Einst... |
Can insects have heart attacks? | Probably not. The reason that we can get heart attacks is because our hearts don't get nutrients from blood they're actively pumping. Instead, blood in the aorta feeds into the coronary arteries, which supply the muscles of the heart. If something blocks those arteries, we get heart attacks.
Like it's stated on the page you linked, insects have an open circulatory system, where fluid flows freely and directly nourishes the tissues, including the "heart", without the need for a detour into something like a coronary artery. | [
"In the fruitfly, knock-down of \"nmr\" (neuromancer), \"Drosophila\"'s Tbx20 homolog gene, led to slower heart rate, arrythmias and abnormal myofibrillar architecture. Heterozygous Tbx20 knockout adult mice displayed left ventricle dilation, decreased wall thickness and contractile abnormalities.\n",
"Vasoconstr... |
what is the difference in sound quality between "mastered for itunes" and an audio cd? | Unless the CD was mastered woefully badly, you're always better off getting a CD than any compressed music (such as iTunes, or using Amazon's auto-rip). There's an off-chance that a badly-mastered CD will be worse quality than a properly-mastered AAC file (or whatever compressed audio you get), but it's not very likely at all.
Unless you're downloading loseless audio (which I think AAC has a version of) - in which case you probably don't want it mastered for any piece of software, but for, you know, humans (: | [
"Mastering, a form of audio post production, is the process of preparing and transferring recorded audio from a source containing the final mix to a data storage device (the master), the source from which all copies will be produced (via methods such as pressing, duplication or replication). In recent years digital... |
how do car keys wirelessly lock/unlock only your car? | They transmit a digital code which only your car responds to.
They're actually rather more clever than that, because you could record this code and play it back to open a car that isn't yours - codegrabbing - so they change the code each time but in a sequence which the keyfob and the car know but which isn't obvious to others.
The sensitivity is because the transmitter is shouting quite loud but only on a very narrow frequency. It doesn't do it very often or for very long, so the battery lasts a long time. | [
"Keychains that currently hold keys are an item that is never long misplaced by the owner. People sometimes attach their keychain to their belt (or belt loop) to avoid loss or to allow quick access to it. Many keychains also offer functions that the owner wants easily accessible as well. These include an army knife... |
how do i practice singing well? | I used to sing in a barbershop chorus, so maybe I can help!
So on a piano, you would practice scales, you do the same but vocally. There are different forms of this, the ones we used for practice improved on scales and our vocal range.
I would search barbershop warm ups, as I can't really explain well in text haha. But to me that's a good thing to follow, as it's all singing and no instruments haha. | [
"Learning to sing is an activity that benefits from the involvement of an instructor. A singer does not hear the same sounds inside his or her head that others hear outside. Therefore, having a guide who can tell a student what kinds of sounds he or she is producing guides a singer to understand which of the intern... |
How did the accretion disk form the stars and planet differently? | The sun **is** the object with the highest abundance of iron. The sun contains more than 43 x 10^24 kg of iron, which is more than 7 times the total mass of earth.
It simply isn't so obvious, because there is so much more hydrogen and helium in the sun. When the solar system formed, the majority of material fell into the sun, icluding heavy elements also. The planets then formed from the leftovers. The young sun blew away the light elements from the inner planets system. That's why the earthlike planets have a high percentage of heavy elemnts and yet a very low mass. Unlike the gas giants they didn't have time to accrete enough mass to become gas giants themselves.
In the early stage of the solar system the composition of elements was more or less uniform, until it became differentiated by the suns radiation and stellar wind. | [
"An accretion disk is a structure (often a circumstellar disk) formed by diffuse material in orbital motion around a massive central body. The central body is typically a star. Friction causes orbiting material in the disk to spiral inward towards the central body. Gravitational and frictional forces compress and r... |
Do peripheral nerves and motor neurons renew or repair? | Schwann cells do have a limited ability to repair. If they're partially damaged, then you of course have a better chance of repairing than if they were completely severed. However, even a complete severance can be repaired. One end releases cytokines to direct the growth of the other end (termed the 'axonal sprout') and hopefully they meet up.
Oligodendrocytes, however, do not repair. Schwann cells are found in the periphery, oligodendrocytes are in the CNS. This is why you can regain function of a hand, but not recover from a severed spinal cord. Oligodendrocytes actively inhibit new growth, the reason for which is in an effort to ward off cancers of the central nervous system (which obviously doesn't always work). | [
"Some studies have revealed that optic nerve fibers can be regenerated in postnatal rats. This regeneration depends upon two conditions: axonal die-back has to be prevented with appropriate neurotrophic factors, and neurite growth inhibitory components have to be inactivated. These studies may lead to further under... |
can someone please explain my credit score li5? | part of your credit score is what's known as Credit Utilization %, the point of it is that someone who is currently having trouble paying off their current credit is probably going to have even more of a problem if they have even more credit available to them.
Now, let's say you have 2 cards with a $5,000 limit, you owe $1,000 on one, and the other you owe nothing on and are considering closing.
Scenario 1: you close the account. You now have $5,000 in available credit and are using $1,000 of it, so you're using 20% of your available credit. That probably doesn't matter much to potential creditors, since 20% is still not too bad.
Scenario 2: You don't close it. You have $10,000 in available credit and are still only using $1,000 of it, but now you're only using 10% of your credit. Potential creditors really like that.
Since Credit Utilization % makes up 30% of your credit score, I'd recommend never closing any line of credit, especially one which doesn't have an annual fee.
By the way, there's more about credit scores in this very subreddit right [Here](_URL_0_). | [
"In the United States, a credit score is a number based on a statistical analysis of a person's credit files, that in theory represents the creditworthiness of that person, which is the likelihood that people will pay their bills. A credit score is primarily based on credit report information, typically from one of... |
How has the office of President of the United States changed over time? | I'm in a hurry so this will be a bit of a hit-and-run, sorry. Will check the thread later for more specific questions.
Scholars of presidential rhetoric and public address have documented a shift in the way the President conducts his office beginning with Theodore Roosevelt and Woodrow Wilson. Before these presidents, the office of the president was not seen as a mouthpiece for the populace of the United States, but rather as simply a branch of the government. So, prior to this time you would not have seen the President touring the country in support of one or more of his policies. For example, when President Andrew Jackson tried to directly appeal to the American people about the National Bank, Daniel Webster answered in rebuke: "But if the President were now to meet us with a speech, and should inform us of measures, adopted by himself in the recess, which should appear to use the most plain, palpable, and dangerous violation of the Constitution, we must, nevertheless, either keep respectful silence, or fill our answer merely with courtly phrases of approbation." The fear was that if the President became a mouthpiece for the people, demagoguery and an unconstitutional expansion of presidential powers would surely follow.
Roosevelt and Wilson represent a shift to the new way of thinking. Roosevelt toured the country several times whipping up popular support for his policies, then used that to try to bully Congress (the term "bully pulpit" emerges here) into passing laws supporting the same. When Congress declined to act on conservation matters, for example, Roosevelt called a "Conference of Governors" and spoke to the governors of the states directly. Wilson also toured the country (most famously in support of his League of Nations proposal) and ceased communicating his wishes to Congress in written messages, preferring to address them (and the United States in general) orally. The rise of the mass media also impacts this, as it made it much easier for the president to directly address the population (think FDR's "fireside chats").
Gotta go - see Jeffrey K. Tulis, *The Rhetorical Presidency* (Princeton, New Jersey: Princeton University Press, 1987) for more, as well as *Beyond the Rhetorical Presidency*, ed. Martin J. Medhurst, College Station: Texas A & M University Press, 1996; Stuckey, Mary, “Establishing the Rhetorical Presidency through Presidential Rhetoric: Theodore Roosevelt and the Brownsville Raid,” *Quarterly Journal of Speech* 92 (2006): 287-309; *Rethinking the Rhetorical Presidency*, eds. Jeffrey Friedman and Shterna Friedman, London and New York: Routledge, 2012; as well as many others, and let me know if I can answer any more specific questions. | [
"In 1946, in response to the rapid growth of the U.S. government's executive branch, the position of Assistant to the President of the United States was established, and charged with the affairs of the White House. Together with the Appointments Secretary the two took responsibility of most of the President's affai... |
If the Higgs Boson is discovered, will this change every day life in the future? | We still have to learn how to utilize the physics from the 1930s for everyday purposes before we consider that of 2012.
Could it be that one day we use it for daily purposes? Surely. Can anybody predict anything about it? Not at all.
| [
"The fact that no decays of the Z boson to the Higgs were observed at LEP immediately implies that the Higgs boson, if it existed, must be heavier than the Z boson (~). Subsequently, with each successive energy upgrade of the LEP, hope re-emerged that discovery of the Higgs was just around the corner. Just prior to... |
how do cryptocurrencies like bitcoin, litecoin, and others work? | The description is long and involved and probably not perfectly ELI5; however, I'll try to do my best.
The first thing to realize is that Bitcoin, Litecoin, and most others all work in exactly the same way; the only difference is a couple of parameters have been changed. The consequences of those changes are not important at this level.
At the heart of this type of currency is the blockchain, which is just a list of transactions that anyone can view--you can take a look at [this](_URL_0_) page to see an example of what a page from this register looks like. This works off of a pretty simple principle: If I know that you have 5 Bitcoins and I see that you give 3 Bitcoins to Sally then I know that Sally now has 3 Bitcoins (assuming she had none before hand) and you have only 2 Bitcoins. It is this type of accounting that is done in the blockchain. You can literally follow any Bitcoin back through its entire history (it gets kind of complicated since coins can be split and merged, but the principle is still valid).
So, who keeps track of that public register? I do. But I don't do it alone--I have thousands if not millions of people helping me. The blockchain is kept by the collective work of all of the computers in the network. Whenever you decide to spend some Bitcoins your computer announces that fact to its friends. Those computers check to make sure that you aren't trying to spend money you don't have (which they can do because they can see how many coins you have received and how many you've spent) and if the transaction checks out then it sends the transaction to more computers, and so on. Eventually every computer in the world knows about the transaction.
This description may make you weary--you have to tell everyone all of your finances--but that is addressed in Bitcoin. Bitcoin is often described as anonymous, but it is more accurate to describe it as "pseudonymous." That is to say, people are represented by their pseudonyms. Just as Samuel Clemens is represented by the name Mark Twain, I am represented by the address 1Aw8UU7Dqx9RweepuDdMkJQVtNNE7SrYqn (and dozens of others--I can create them at will). Without knowing the names associated with these addresses it is impossible to figure out who is sending or receiving the money.
******
Another topic to be aware of is "mining," the name of which I really dislike since it completely disregards the primary purpose of the act. When you send a transaction that says that you send 3 Bitcoins to Sally I can check and make sure that that transaction is valid, but you could also make a transaction that says you send 3 Bitcoins to Jeff, and you could tell computers in China that *that* is the transaction you intend to send. I can verify that your transaction to Sally is valid and someone in China could verify that your transaction to Jeff is valid, but when someone sees *both* transactions they have to figure out which one to accept--in fact, the *whole network* needs to come to an agreement as to which one of those transactions is valid and which one should be ignored.
In order to solve this problem computers vote on which one to choose. The system could have been set up so that each computer gets one vote, but that opens the system up to people who could pretend to have lots of computers by getting lots of IP addresses. Instead of one computer, one vote, Bitcoin uses essentially one CPU, one vote. That is to say, in order to cast a vote you have to solve a math problem. This problem is not that hard--computers can solve the problem hundreds of millions of times per second--but it takes some amount of time to do and faster computers get more votes. That is the heart of the system. I should mention that this is a horrifically simplified description of what goes on in "mining." If you want I'd be happy to go into more technical detail--I'm trying to stay as ELI5 as possible and getting into the properties of cryptographic hash functions isn't standard five-year-old material.
The people who are undertaking this process of mining are running their computers as hard as they can, often 24/7. This takes a certain expenditure of time, effort, and money--both for hardware and electricity. In order to compensate them for this time they receive Bitcoins--about every 10 minutes 25 new Bitcoins come into existence and are issued to one of the people mining. At over $100 per Bitcoin that makes it worth it to a lot of people to try to compete to be the person who the reward is given to.
******
The final thing to understand is the idea of a wallet. A wallet is just a file on your computer, but the term is also used to describe the program that uses the wallet. Unlike a real wallet, which contains cash, a Bitcion wallet contains keys. This means that if you copy your wallet you don't double your Bitcoin any more than you double your house when you get a copy of your door key made. These keys can be thought of as being to a public lock box--anyone can put Bitcoins into your lock box but only you can take them out. An important side effect to this is that if someone gains access to your keys (wallet file) then they can take your Bitcoins. Add to that the difficulty of tracking individuals in Bitcoin and you have the makings for a very profitable heist--Bitcoin essentially lets people be their own bank by giving them the tools to secure their money; with the sudden increase in the number of small "banks" there was a corresponding increase in the number of small bank *robbers,* who target the people who don't use the security tools available.
There are many wallet programs available, but the most popular seem to be the "Satoshi" QT client, which is the original; Electrum, which is a light weight version that takes fewer computer resources; and _URL_1_, which offers an online wallet--online wallets are inherently less secure but they do a good job of being as secure as they can and they offer an easy and free service.
******
I'm sure that there are plenty of other areas that I could go into. If there's something about Bitcoin you'd like to learn more about just ask and I'll do my best to explain. When I first learned of Bitcoin 2 and a half years ago I was absolutely *certain* that it was a scam, a pyramid scheme, or some other sort of hogwash that shouldn't be given the time of day. However, I've since gone and studied it in-depth and I think it's poised to be a very disruptive technology in the payment processing industry (vs Credit Cards, PayPal, Western Union, etc) and could even be used as a national currency in a nation in turmoil (this was seen to some extent with some of the Cyprus issues earlier this year). | [
"Bitcoin, first released as open-source software in 2009, is generally considered the first decentralized cryptocurrency. Since the release of bitcoin, over 4,000 \"altcoins\" (alternative variants of bitcoin, or other cryptocurrencies) have been created.\n",
"The cryptocurrency community refers to pre-mining, hi... |
why do lizards run in front of me as i walk on the sidewalk? | They are just like squirrels that wait until a car rolls by before they dart across the road. They're bored and want to cheat death for fun. | [
"Aside from legless lizards, most lizards are quadrupedal and move using gaits with alternating movement of the right and left limbs with substantial body bending. This body bending prevents significant respiration during movement, limiting their endurance, in a mechanism called Carrier's constraint. Several specie... |
how do terrorist groups like isis convince young girls in western countries that life is better in iraq/syria? | Generally, they have luck with any group because of outsider politics. Plenty of people feel marginalized and useless in Western society. Groups like ISIS preach a very well-defined set of social rules, in which these marginalized people imagine their life can matter.
While objectively, people seem to be giving up a wide array of rights, they perceive it as gaining a proper sense of community and purpose, things which generally matter more to people. | [
"According to figures collected by the Soufan Group in 2016, between 27,000 to 31,000 people including women and children who would not normally engage in conflict had traveled to Syria and Iraq to join the Islamic State and other extremist groups fighting in the region.\n",
"The Syrian women in conflict areas we... |
How do muscles absorb energy? | Your muscles take in the force by resisting the motion, you burn energy (calories) (and create heat inside the cells) to produce the power needed to reduce the speed of the bike.
Basically don't think of it as "stopping the bike" but rather "exerting a force". Its the same process to stop it as to start it, different muscles yes, but the design of the power train is the same.
Your byproducts are heat, inside the muscles, the acid leftover from burned glucose, and carbon dioxide. | [
"Muscular activity accounts for much of the body's energy consumption. All muscle cells produce adenosine triphosphate (ATP) molecules which are used to power the movement of the myosin heads. Muscles have a short-term store of energy in the form of creatine phosphate which is generated from ATP and can regenerate ... |
why does some antivirus protection software (norton, mcafee, etc.) make your computer run worse than it did before? | Think of it this way.
Let's say that you're a company that receives a lot of postal mail. You could have the mailroom receive that mail, then take it directly to the recipient. That's your computer without antivirus.
Alternatively, your company could have a room directly next to the mail room. The mail room receives a letter and gives it to the people working in that room. They open each and every letter and look for the contents of that letter in an old-fashioned 30-volume encyclopedia. If they find it in the encyclopedia, they throw it away. If they don't, then they put it back in the envelope, send it back to the mailroom and the mailroom then takes it to the recipient. That's your computer with antivirus.
Antivirus slows your computer down because that's what it's doing constantly poking at what's going on inside your computer and asking "is that a virus? No. Ok go ahead." Now, it's a computer program, so it's pretty fast at the encyclopedia search, and it has ways to speed it up. But, still that takes time. And, that's why your computer is slow.
For that reason, it's still true that if you want to download and install a large software package (especially an uncommon package), turning off the antivirus can speed up that process dramatically because it removes the "let's check the encyclopedia" check. | [
"Real-time protection from malware works identically to real-time antivirus protection: the software scans disk files at download time, and blocks the activity of components known to represent malware. In some cases, it may also intercept attempts to install start-up items or to modify browser settings. Because man... |
What color were Spartan shields? | First thing to note is that *300* did the shields wrong on purpose. Zack Snyder figured that all-metal shields with the double grip across the middle would look cooler than the real thing. I can't really fault him for that, as he was making a movie, not writing history. But don't be distracted by what you see. (I've written more about the inaccuracies of *300* [here](_URL_1_).)
The actual hoplite shield (called *aspis*) was made of alternating layers of strips of wood. It had a double grip of which the loop for the elbow was in the exact middle of the shield, with the loop for the hand all the way on the right edge. The rim of the shield was reinforced with bronze. Some shields were entirely coated in a thin ( < 1mm) layer of bronze, while others simply had a wood facing. Either could be decorated with paint. Before the Persian Wars, every hoplite could pick whatever blazon he wanted for his shield, but afterwards some cities appear to have gone for a standard symbol or letter.
Spartan shields were known for two things: one, they were all covered in bronze, and two, they had the capital Λ on them, which stood for Lakedaimon (the region Sparta was in). Xenophon and Plutarch both claim the Spartans polished their shields before battle, and Xenophon likes to stress how the Spartan phalanx looked like a single mass of red and bronze, which means the shields must have had a bronze coating. Other sources report that they could be recognised from their lambdas. Given the references to shining bronze, it is clear that significant parts of the shield would have been unpainted. To my knowledge, no source says anything about the colour of the lambdas - I'd be glad to be proven wrong on this if you can find the reference. It is possible that the lambdas were red; it is also possible that they were another colour; it may even be that the shields were red and the rims and lambdas unpainted bronze.
The interesting thing is that the earliest references to the Spartans' famous lambda shields (in Eupolis) and to their red tunics (in Aristophanes) date to the late fifth century BC. In his detailed description of the battle of Thermopylai, Herodotos says nothing about the nature of Spartan shields or clothing. Most likely the Spartans simply did not yet have their iconic outfit at the time of the battle (480 BC). Each Spartan will have been dressed according to his own preference and the blazon on his shield will have been an emblem of his choice. It may be accidentally true to history that the modern statue of Leonidas set up at Thermopylai (made in 1955) doesn't feature a lambda on the shield, but a [gorgon's head](_URL_0_).
Since the Spartans did not have uniform equipment before the Peloponnesian War, it is impossible to identify them on vases. I know of no vases that unambiguously portray Spartans, unless there is direct reference to Menelaos in Homeric combat scenes. There is only the extremely questionable theory that the warriors on the infamous Chigi Vase are Spartans because they are accompanied by a piper, and Thucydides says the Spartans marched to the sound of pipes - *two and a half centuries later.* I personally do not buy this at all. There really is nothing we can say about Spartan shields from pictorial evidence unless we go in for a circular argument ("Spartan shields are red; the shields on this vase are red; therefore these are Spartans").
tl;dr: we know much less about this than we would like. The probable answer is that Spartan shields were the colour of their bronze facing, with lambdas painted on them in an unknown colour. | [
"The Leukaspides ( \"White Shields\"), may have made up one of the two probable corps of the Antigonid Macedonian phalanx in the Hellenistic period, with the \"Chalkaspides\" (\"Bronze Shields\") forming the other. However, this conclusion is contested, as the Thracians at Pydna also had white shields (as did many ... |
When Sun Tzu released The Art of War, wasn't he worried that enemies would use his own tactics against him? | The short answer to this is that we have no way of knowing for certain why The Art of War was written, how it was initially used, or even if Sun Tzu was actually the author. The traditional version of events, which is generally but not invariably accepted, is that Sun Tzu lived during the Spring and Autumn period of Chinese history (771-476 BCE). He is thought to have been born in 544 BCE and died in 496 BCE, about 20 years before the beginning of the Warring States period. According to Lionel Giles, the British translator who made the first full – and most frequently used – English translation of The Art of War (in 1910), he was a native of the state of Wu, and his work was written for the then King of Wu, Helu, around 500 BCE.
Even this is disputed by some authorities; for example, Ralph Sawyer, the American military historian, has suggested that what we now have may be an original text substantially modified later by Sun's disciples – although Sawyer does accept that the descriptions of warfare that The Art of War contains can probably be matched to known campaigns fought by Wu against its enemies, Chu, Qi and Qin around this time.
It has also been suggested that the author was actually a relative, Sun Bin. This latter theory has become less popular in recent years thanks to the rediscovery of Sun Bin's own book (1972).
So ascribing any particular motive or concerns to Sun Tzu or anyone else is problematic; we simply have no evidence to tell us how the book was supposed to be used or its secrets protected. One might surmise that it was commissioned by Helu and written to be read by him; but the idea it was "widely published" is also hard to comment on. It could only have been circulated as a copied manuscript, of course, so it would certainly not have been as widely available as the term "published" suggests, and it would have been easier to restrict its circulation then than would be the case today. More than that is hard to say, as we have no evidence of how the work was received when it was written and the commentaries and responses that we have to it date to hundreds, and in many cases thousands, of years after it was completed. | [
"The translator Samuel B. Griffith offers a chapter on \"Sun Tzu and Mao Tse-Tung\" where \"The Art of War\" is cited as influencing Mao's \"On Guerrilla Warfare\", \"On the Protracted War\" and \"Strategic Problems of China's Revolutionary War\", and includes Mao's quote: \"We must not belittle the saying in the b... |
In the roman empire, why did the people from the provinces not trust the senate? | Hm. I don't actually know what you are referring to.
Are you talking about any specific incident or event? Any particular time period? Any specific province?
Are you referring to the Roman Empire (I.e. the time after Augustus, when Rome was ruled by an emperor) or do you perhaps mean the time of the Republic? The senate continued to exist in the Roman Empire, but it didn't make many important decisions anymore... at least without prompting from the emperors. But the Senate did still provide many provincial governors.
So: We'll need you to provide some more information so we can be sure what it is you're actually asking. As is, I doubt anyone will be able to help you. | [
"The Senate was the predominant political institution in the Roman Republic. The Senate's authority derived primarily from custom and tradition. It was also one of the few places in which free political discussion could take place. The Senate's principal role was as an advisory council to the consuls on matters of ... |
Why did Winston Churchill launch the Dardanelles Campaign? | This is slightly modified from an earlier answer of mine, posted [here](_URL_0_)
The Gallipoli Campaign is, all too often, portrayed in popular culture (games like *Battlefield One* or films like *Gallipoli*) as an independent operation carried out to take Istanbul. This removes the campaign from its historical context. Instead of being an independent operation, it was part of a naval campaign against the defences of the Dardanelles strait. The aim of the campaign was not to put an army into Istanbul. Rather, it was to put a fleet into the waters off Istanbul. This could only be done by travelling through the Dardanelles, but as matters proved, doing so required landing troops to clear out the Ottoman fortifications defending the strait.
To understand the operation, a map will be useful - [this one](_URL_1_) from the RN's official history is a good one. Looking at it, you can clearly see the defences of the strait. These were divided into two main groups: the outer defences, the forts protecting the entry to the strait, and the inner defences, the forts along the inside of the strait preventing any ships that had successfully avoided the outer defences from sailing through the strait. The defences came in four main forms: guns, mines, torpedoes and floating mines. The torpedoes were fired from fixed tubes on land, and played no part in the campaign. Floating mines (mines that were not moored, but were released into the current), were rarely used, and were easily dealt with by Allied minesweeping preparations. As we shall see, the combination of moored mines and guns were to have a great effect on Allied naval operations, and ultimately forced a landing to deal with them.
Allied naval operations against the Dardanelles began on the 3rd November 1914, when the battlecruiser *Inflexible* bombarded the outer defences. This had little material effect on the defences, but showed the Ottomans the vulnerability of their defences, leading them to greatly bolster their positions, adding many new batteries and laying more minefields. The risk that the bombardment might do so had been accepted by Allied commanders, as this was essentially intended as a one-off operation, rather than as a prelude to further attacks. However, in January 1915, frustrated by the refusal of the Admiralty to countenance his plan for an invasion of the German islands of Sylt and Borkum, Winston Churchill (First Lord of the Admiralty, the civilian head of the Royal Navy), asked Vice-Admiral Carden, commanding the British forces in the Eastern Mediterranean, if he thought “the forcing of the Dardanelles by ships alone a practicable operation." Churchill hoped that, by putting a British fleet into the Golden Horn, it would cut Ottoman logistics to the Caucasus and Sinai fronts, and provoke the public into action against the Ottoman government. Jackie Fisher, the First Sea Lord (military head of the RN), was generally favourable to an operation against the Dardanelles, but believed that it was impractical without troops to suppress the forts. Churchill, however, remained steadfast, and was supported in his position to a certain extent by Kitchener and the Army, who were unwilling to release troops for peripheral operations. Several other possibilities for operations against the Ottoman Empire had been suggested. In the pre-war period, a landing at Haifa had been suggested. A landing at Alexandretta (now İskenderun), which would cut the main road and rail links between Baghdad and Constantinople, was also considered. These options were discarded due to a lack of resources, with Churchill focusing naval resources entirely on a campaign against the Dardanelles, and French diplomatic objections, which saw the plans as a threat to France's interests in Syria and Lebanon. On the 13th January 1915, the War Council recommended that the Royal Navy ‘bombard and take the Gallipoli Peninsula, with Constantinople as its objective’. This was accepted by the RN on the 28th January, but even before then, Churchill had begun to strengthen Carden's force at Malta.
The Dardanelles Campaign began on the 19th February, with an unsuccessful bombardment of the outer forts by the Allied force. At the time, the bombardment force consisted of five old battleships (*Cornwallis*, *Albion*, *Triumph*, *Suffren* and *Bouvet*) and *Inflexible*, with two more old battleships (*Vengeance* and *Gaulois*) and the cruiser *Amethyst* positioned to observe the fall of shot. The fleet began by steaming slowly past the forts, opening up a slow and deliberate, though inaccurate fire. They then anchored to increase accuracy, though *Cornwallis* had to exchange positions with *Vengeance* due to a broken capstan. At about 5pm, *Agamemnon* and the new super-dreadnought *Queen Elizabeth* joined the bombardment, but Carden withdrew about 20 minutes later, thanks to failing light, lack of ammunition and the risk of torpedo attack. The fort had successfully damaged the fort at Kum Kale, and suppressed most of the other forts in the outer defences. It was intended to follow this operation with another on the 20th. However, poor weather forced a delay until the 25th. This delay did allow two battalions of Royal Marines to join the fleet, which would be used as demolitions parties. Equally, it allowed the Ottomans to bolster their defences and repair the damage done on the 19th.
The bombardment on the 25th was much more successful than that on the 19th. The Allied commanders had learned that merely bombarding a fort would not prevent it from firing; each gun had to be put out of action with a direct hit. Fire was opened at about 9:50, and though *Agamemnon* and *Gaulois* were hit by fire from the battery at Helles, by midday, all the forts had successfully been suppressed from range. The fleet then closed to complete the silencing of the forts. By 3pm, it had been decided that the forts had been fully suppressed, and minesweepers began to clear the waters around the entry to the straits. The next day, ships began to enter the Dardanelles themselves. The plan was for one battleship, preceded and followed by minesweepers, to pass down either coast of the strait. The two ships chosen were *Albion* and *Triumph*, though in a slight change to the plan they were joined by *Majestic*. Their first duty was to destroy the forts at Sedd el Bahr and Kum Kale from inside the strait, where their defences did not cover. This was quickly achieved, and they then moved on to the initial suppression of the inner defences. While this was relatively successful, they were harassed by fire from concealed batteries of mobile field guns and howitzers, which had been added since the original bombardment on the 3rd November 1914. Meanwhile, outside the straits, the Marines were landed. They successfully demolished the batteries at Kum Kale, Orkanie and Sedd el Bahr, though they were beaten back from the battery at Cape Helles.
Once again, the weather closed in, though on the 27th, another landing party managed to destroy six heavy mortars at Sedd el Bahr. While landings had been planned for the 28th, these had to be cancelled due to the weather. However, the battleships and minesweepers re-entered the straits to engage the southern portion of the inner defences. This attempt was a lot less successful than those of the previous days. From the moment they entered range, they were brought under a heavy fire from the concealed Ottoman batteries. None of this did much damage, but it forced the ships to continually move to avoid being hit, greatly reducing their accuracy. While a demolition party had successfully been landed to complete the destruction of Kum Kale, little had been achieved. Operations continued in this vein over the next few days - relatively unsuccessful bombardments inside the straits while demolitions parties mopped up the outer defences. The concealed batteries were a major part of the problem. They used guns with a higher trajectory, allowing them to be positioned in dead ground behind hills or ridges. Here, they could fire unimpeded, using spotters to correct their fire, while the battleships could not see their position to fire upon them, nor hit them with their lower-trajectory main guns. While they did little damage, they prevented the battleships effectively firing upon the forts and batteries that were the real threat to them.
The batteries were considerable danger to the minesweepers in the fleet. Mines were a major threat to the older battleships which made up the bombardment force, as they had been designed with poor protection against flooding. As such, sweeping the mines was key to the operation. The sweepers used were requisitioned trawlers, which were poorly suited for the task at hand. They were slow, capable of making just five knots when sweeping. When you consider that the current in the straits could reach up to four knots, which the sweepers had to work against, the problem should be clear. The sweepers also had a draught greater than the depth at which the mines were moored. The sweeps they used were poorly suited for operation under fire, as they had been designed for use in British coastal waters - it required the sweepers to painstakingly tow any mine they caught into shallow water, where they could be sunk by rifle fire. Finally, they were manned by inexperienced crews, and had generally poor morale. As a result, British minesweeping efforts were generally ineffective.
| [
"The Dardanelles Campaign was an attempt by Churchill and those favouring an Eastern strategy to end the stalemate on the Western Front. It envisaged an Anglo-French landing on Turkey's Gallipoli Peninsula and a rapid advance to Constantinople which would see the exit of Turkey from the conflict. The plan was rejec... |
Did most non-Europeans in the British Empire convert to Christianity? | No, definitely not. By far the most populous part of the British Empire was India, where Christianity is a very small minority of only a couple of percent. | [
"In most of Britain, the native Britons were already partly Christianized by the time of the Anglo-Saxon settlement of Britain; it is not clear how thorough this process had been. Ireland, and parts of Scotland, had been converted by the Romano-British Christians, led by Saint Patrick. However, ecclesiastics of the... |
Is it possible to freeze water by surrounding it with ice cubes/blocks? | It certainly is possible to freeze a body of water by having a block of ice act as a heat sink. In order to simplify things we can ignore all additional heat sources/sinks and consider just the liquid ice/water system. The factors that will determine whether the ice will eventually cause the water to freeze are: the temperature of the water, the temperature of the ice, and the mass of each.
In order to freeze water you need to do two things: 1) first you need to cool the water from its initial temperature, Tw to 0C, then 2) you need to crystallize the water to form ice. Both of these events require energy to be removed from the system in the form of heat. The energy needed to be removed in 1) is given by Tw\*Cw\*mw, where Cw is the specific heat capacity of water (about 4J/(g\*K)) and mw is the total mass of the water in grams. In the second step, energy needs to be removed because crystallization results in the release of heat, the so called enthalpy of fusion. For water the specific enthalpy of fusion (the amount of heat generated per unit mass) is H=330J/g, so the total heat that needs to be removed is H\*m, so 330J/g*m.
Now the question is whether the ice can absorb all this energy without melting. Immediately we can see that the ice needs to be colder than 0C, or else any of the heat from the water will simply go into melting the ice. However, if say the ice was at a temperature Ti, then it can absorb Ti\*Ci\*mi energy, where mi is the mass of the ice and Ci is the specific heat capacity of ice, which is around 2J/(g\*K) before the ice reaches 0C and begins to melt.
Putting it all together, the ice will cause the water to freeze as long as the energy it can absorb in heating up to 0C is enough to cool the water and compensate for the heat released when the water will freeze. Put mathematically, the water will freeze as long as the following inequality is satisfied:
Ti\*mi\*Ci > Tw\*mw\*Cw+ H\*mw. | [
"Cube ice machines are commonly seen as vertical modular devices. The upper part is an evaporator, and the lower part is an ice bin. The refrigerant circulates inside pipes of self-contained evaporator, where it conducts the heat exchange with water, and freezes the water into ice cubes. When the water is thoroughl... |
Why do some areas of Earth have far less lightning storms than other areas? | To have lightning you usually need rapid temperature changes in a region with decent humidity. Those conditions are not present at all locations at all times of the year. A thunderstorm usually occurs with intense heating of the (usually humid) ground which then cause hot moist air to rise into cooler air above. If this vertical wind is strong enough water droplets or ice crystals form, fall part way and then are pushed back up through the cloud growing larger with each pass, before finally becoming too heavy to stay up and falling as very intense rain or hail. These vertical vortexes of warm moist air through cooler, dryer surrounding air also separate charges, similar to rubbing your socks on the carpet. The static charge is released as giant sparks between clouds or between the clouds and the ground. You need specific temperature changes, humidity levels and surface features to allow the sequence of events needed for lightning. | [
"This occurs from both the mixture of warmer and colder air masses, as well as differences in moisture concentrations, and it generally happens at the boundaries between them. The flow of warm ocean currents past drier land masses, such as the Gulf Stream, partially explains the elevated frequency of lightning in t... |
how our respiratory system knows, that there is enough oxygen in air to breathe correctly? | It doesn’t know. As long as you aren’t in a vacuum, the suction cause by your diaphragm will fill the lungs with whatever gases are around you. From there your blood chemically reacts with the oxygen to take it through the body.
If you were breathing 100% helium, you wouldn’t feel like you couldn’t breathe. You’d get drowsy and go unconscious. That’s why carbon monoxide is a killer-your body prioritizes it over oxygen, you don’t know it’s there (odorless, colorless), you don’t feel like you’re suffocating and then BOOM you’re dead | [
"Breathing (or ventilation) is the process of moving air into and out of the lungs to facilitate gas exchange with the internal environment, mostly by bringing in oxygen and flushing out carbon dioxide.\n",
"The most important function of breathing is the supplying of oxygen to the body and the removal of its was... |
Are the physical remains of the Apollo missions that are still on the moon, are they U.S. government property, or public domain? | Just so you know, this is a question about *space law*, which above all else is a subset of international law. That means that anything discussed about space law has to be viewed in the context of the enforceability and credibility of international law. Also, it's not *really* history question.
The 1967 Outer space Treaty is the relevant document.
Article VIII says that you retain ownership even when it leaves the planet.
> A State Party to the Treaty on whose registry an object launched into outer space is carried shall retain jurisdiction and control over such object, and over any personnel thereof, while in outer space or on a celestial body. Ownership of objects launched into outer space, including objects landed or constructed on a celestial body, and of their component parts, is not affected by their presence in outer space or on a celestial body or by their return to the Earth. Such objects or component parts found beyond the limits of the State Party of the Treaty on whose registry they are carried shall be returned to that State Party, which shall, upon request, furnish identifying data prior to their return. | [
"The Apollo 11 plaque display given to Sweden by President Nixon in 1970 was reported missing by the Swedish Museum of Natural History in Stockholm on September 7, 2002. The museum had exhibited them in a stainless steel cylinder with a glass plate over the top. Museum employees found the viewing glass plate broken... |
how does salt water conduct electricity and normal water does not? | So salt is composed of two elements, Sodium, a metal and Chlorine, a non-metal which makes NaCl. Metals like sodium form what are called positive ions and non metals like chlorine form negative ions. These two ions are attracted together and form a bond. However when put into water the bonds break up and the water is full of sodium and chlorine ions. these ions are able to carry the charge of the electricity. | [
"Because water is such a good solvent, it almost always has some solute dissolved in it, often a salt. If water has even a tiny amount of such an impurity, then the ions can carry charges back and forth, allowing the water to conduct electricity far more readily.\n",
"Salts are characteristically insulators. Molt... |
hiv came from siv, which affected primates...but where did siv come from? how did siv become what it was/is? ultimately, what created hiv? do we know? | The SIV that affects chimps (edit: I should clarify that one of the two HIV strains likely evolved from this, the other being from mangabeys) appears to be a combination of SIVs that infect mangabeys and spot-nosed monkeys, which chimps hunt. We have found evidence in lemurs (non-simian ancestors) that this whole "family" of viruses goes back at least 14 million years when mammals in Madagascar and mainland Africa last intermingled. If that's not how it was transferred and the virus evolved with the primate lineage, that pushes it back to 85-ish million years.
Beyond that, we don't know. Viruses aren't like complex animals that reproduce and provide fairly straightforward lineages. They can combine and mutate very quickly and in ways that are hard to back-track, and their "ancestry" gets muddied up pretty quick. | [
"The majority of HIV researchers agree that HIV evolved at some point from the closely related simian immunodeficiency virus (SIV), and that SIV or HIV (post mutation) was transferred from non-human primates to humans in the recent past (as a type of zoonosis). Research in this area is conducted using molecular phy... |
how do sea animals avoid getting swept into the sky during hurricanes like cows do in tornadoes? | Some do, more with water spouts than hurricanes, but it’s still possible. That’s why there’s reports of animals raining from the sky dating way back through history.
It’s rare, but it does happen. | [
"When tropical cyclones move over land, they often produce the wind shear and atmospheric instability required for the development of weak, embedded supercell thunderstorms, which can produce tornadoes. These tornadoes are usually weak and short-lived, but still capable of producing significant damage. While center... |
[META] This is one of the few subreddits that has maintained a high level of quality and professionalism over time, thank you. | This thread has been removed due to bootlicking. | [
"Post 20th century, as a result to much debate of ethical guidelines, many organizations such as ABET offer ethical accreditation to University or College applications such as \"Applied and Natural Science, Computing, Engineering and Engineering Technology at the associate, bachelor, and master levels\" to try and ... |
Can somebody help identify a battleship for me? | The ship is an American pre-dreadnought battleship of the *Connecticut* class, though I don't know enough about said class to determine which ship within the class it is. The cage masts are obvious signs that this is an American ship, as no other major navy used them. The first way we can identify the class is to look at the funnels. The USN only built three classes of pre-dreadnought with three funnels; the *Connecticut*s, the *Virginia*s and the *Maine*s. There are also two armoured cruisers with three funnels, *New York* and *Brooklyn*. To tell which class it is, we look at the armament. All of these ships had two large turrets fore and aft. However, on the *Virginia*s, these also had a second turret, containing a portion of the secondary armament, on top of them. As this ship doesn't have these, we can rule out this class. The *Maine*s and *New York* did not have a secondary battery in turrets, so we can rule them out. *Brooklyn* only had four turrets, so she can be ruled out, as we can see six turrets. As a result, the *Connecticut* class is the only possibility. | [
"The Battleship New Jersey Museum and Memorial is located at 62 Battleship Place, Camden, New Jersey, United States. This museum ship preserves and displays , the most decorated battleship to have served in the U.S. Navy and one of the largest ever built.\n",
"While the battleships were under construction, discus... |
In Westerns, it's common to see wanted posters with a reward offered in lieu of an organized, coordinated effort by law enforcement to track criminals down; was this an accurate reflection of how the system worked, or a fictional convention? Who would usually be offering these bounties? | While you're waiting for someone to answer your question in particular, you might be interested in perusing [the section of the FAQ on the historical accuracy of "Wild West" tropes.](_URL_0_) | [
"Wanted posters for particularly notorious fugitives frequently offer a bounty for the capture of the person, or for a person who can provide information leading to such capture. Bounties provided an incentive for citizens to aid law enforcement, either by providing information, or by catching the criminal themselv... |
How do we know light speed is the universal speed limit? For example, if light moves differently in a gravitational field, we'd never be able to gather any data to the contrary on Earth. | We only "know" in the sense that it hasn't been proven false yet.
The idea of *c* being constant in all reference frames is a direct result of special relativity, and being constant in all frames implies an absolute speed limit in the universe. Thus far, no experiment has been performed that suggests special relativity may be incorrect, and until that happens, we take the theory and everything that can be derived from it as true.
As an aside, this is a subtle point about science that some people fail to understand - scientists never produce a theory, sit back, dusts off their hands and say they're done. All theories are constantly being tested in new ways and with greater precision, looking for holes to be fixed. | [
"The paradoxical aspect of each of the described thought experiments arises from Einstein’s theory of special relativity, which proclaims the speed of light (approx. 300,000 km/s) is the upper limit of speed in our universe. The uniformity of the speed of light is so absolute that regardless of the speed of the obs... |
why do computer manufacturers still include usb 2.0 ports alongside 3.0 ports? | There are a few reasons you still see USB 2.0 alongside USB 3.0.
1) The Input/output chip found on Intel computers (Which is most computers you buy) only provides 6 USB 3.0 ports on desktops and 2 on mobile. This is a big limiter.
2) It increases design complexity, there are 9 wires in 3.0 vs 4 in 2.0. Multiply that difference by how many ports we have 3.0 over 2.0 and you end up with a bunch of extra space used just for wiring. Going above the 6or 2 from 1) and you're adding extra chips and even more wiring yet.
3) It costs more for the manufacturer to add more USB 3.0. Each of those chips to add USB 3.0 ports costs around 5-7$, each adding 2 ports, or around 10$ if it adds 4 ports.
4) For the added cost and complexity, the majority of uses for USB ports don't need the extra speed. Input devices, various adapters, even USB sticks tend to be more than happy with what USB 2.0 can provide. Mass transfer to external hard drives, SSDs or high performance USB sticks are almost the entirety of devices that benefit from USB 3.0. More than 2 of these won't be used at a time very often.
5) More USB 3.0 add-on controllers will take bandwidth away from other parts of the system. Add too many and something will need to give out, such as running your GPU with half it's normal bandwidth or lowering internal expansion.
6) Legacy, modern Windows 8 or 8.1 tend to be happy to work on USB 3.0 out of the box (especially with the built in Intel or AMD ports) but Windows 7, various Linux distributions or tools that run outside of Windows won't always work. | [
"If faster connections to storage devices are the reason to consider USB 3.0, an alternative is to use eSATAp, possibly by adding an inexpensive expansion slot bracket that provides an eSATAp port; some external hard disk drives provide both USB (2.0 or 3.0) and eSATAp interfaces. To ensure compatibility between mo... |
How were black ambassadors treated by America during the Civil Rights Era | Copying a post I made on this a few months ago:
> Segregation was a major headache for the State Department from post-WW2 until the passage of the Civil Rights Act. They spent a lot of time soothing ruffled feathers of African diplomats - it was quite common for them to be harassed when travelling between Washington and the UN, particularly when passing through Delaware. Not to mention the problems organizing things like lunch meetings in segregated DC. State advocated strongly for the passage of the Civil Rights Act because of this; they argued for it as a national security issue, since the US wanted the countries sending these black diplomats as allies in the Cold War.
> A source article on this: "No Diplomatic Immunity: African Diplomats, the State Department, and Civil Rights, 1961-1964" by Renee Romano, The Journal of American History. [You can access it free online.](_URL_0_) | [
"On July 26, 1963, Allen spoke before the U.S. Congress and the nation in support of what became the Civil Rights Act of 1964. He was the only prominent white southern elected official to do so. As a result, there were death threats made towards the Allen family, and many white friends and constituents never spoke ... |
What gives old-time radio its distinctive sound? Would it have sounded similar to contemporary listeners? | It's kind of an "all of the above" situation. Poor frequency response and distortion specifications on recording gear, the fact that recording compensation wasn't well understood at the time resulting in difficulty accurately capturing sound to a record, limitations of playback technology (poor frequency response of the pickup), limitations of broadcast technology (poor modulation, etc.) poor frequency response and distortion specifications on amplifiers and speakers...
Pretty much the entire signal chain was lo-fi back then. It would have sounded much the same to those listeners as it does today.
It was like magic at the time, though. Just a few years prior, you hired a musician if you wanted music, there just wasn't another option. Low fidelity recordings were a miracle of convenience and innovation that only continued to improve with time. | [
"Sounds of the Seventies is a BBC radio programme broadcast on weekdays, initially 18:00–19:00, subsequently 22:00–00:00, on Radio One during the early 1970s. Among the DJs were Mike Harding, Alan Black, Pete Drummond, Annie Nightingale, John Peel (who alone had two shows per week), and Bob Harris. For contractual ... |
how has the fcc gone from battling verizon in court to preserve net neutrality to now trying to destroy it, in 3 months? | I would not say the FCC is trying to destroy Net Neutrality.
They lost the court case, and in losing the case they lost the ability to enforce regulations on Internet Service Providers (ISPs). Now they can get that ability back but it would take an act of congress to do so. This leaves the FCC in the position of either doing nothing, or waiting for congress to enact legislation allowing the FCC to enforce net neutrality laws (and doing nothing until this happens).
As these kinds of changes have not even been proposed in congress, the FCC can only wait That is what you are seeing with the FCC. They have no options but to wait until new laws give them power again. | [
"On January 14, 2014, the DC Circuit Court of Appeals struck down the FCC's net neutrality rules after Verizon filed suit against them in January 2010. In June 2016, in a 184-page ruling, the United States Court of Appeals for the District of Columbia Circuit upheld, by a 2–1 vote, the FCC's net neutrality rules an... |
What did Ethiopians themselves call their country during the 12th century? | Well, most probably "Ethiopia" or at least the local Geʽez and Amharic language version: "ʾĪtyōṗṗyā." The name was already being used internally. Also possibly something along the lines of "Habeshat."
While you've followed the typical scholarly use of Axum, there's a little more to it than that. Axum was never the name for the whole empire in the eyes of the Axumites themselves, much in the same way that Egypt did not consider Canaan to be Egyptian, the Persians did not consider Lydia to be Persian, Alexander did not consider Bactria to part of Greece, or England did not consider Ireland to be English at various points in time. These are the full titles of King Ezana, the 4th century Axumite king who first converted to Christianity:
> \[King of\] Aksum, Himyar, Kasu, Saba, **Habashat**, Raydan, Salhen, Siyamo, Beja, king of kings, son of the unconquered Mahrem
That's the list in Ge'ez, there's another, very similar list in Arabic, and a third in Greek:
> King of the Aksumites, the Himyarites, Raeidan, the **Ethiopians**, the Sabaeans, Silei, Tiyamo, the Beia, and Kasou, king of kings, son of the unconquered Ares
So not only can you see how "Axum" encompassed a range of native and conquered people within their empire, but also the earliest use of "Ethiopia" in the region. The Axumite Empire had direct contact with Rome and interacted with Greek ambassadors. They probably even had a small Greek speaking population. This introduced the Greek word "Aithiopia" to the region for the first time. Originally that word was just the Greek term for "black Africans." That's the way it is used in Classical Greek and Biblical sources. The Hebrew word translated to Greek as "Aithiopia" was "Kush." Kush referred, more specifically, to the region of modern Sudan, often called Nubia in modern ancient scholarship. It was probably around this time in the 3rd-4th centuries CE, when the Axumites had more regular contact with the Romans that "Aithiopia" started to take on the more modern meaning.
Meanwhile, we have the early-modern word "Abyssinia" to deal with to. Ethiopia never started referring to itself as Abyssinia internally. Abyssinia was a European exonym. The Ethiopians may have used that form in their dealings with Europeans, once they started having regular dealings, but it was not a native word. Instead, "Abyssinia" is a latinization of the Arabic name for Ethiopia: "Habashat." This is also the name used in Axumite Ge'etz above and is probably the ancient native name that was most directly usurped by "Ethiopia."
The answer to your original question is thus somewhat unclear. We know comparatively little about Ethiopian politics in the 10-12th centuries, compared to the preceding \~1000 years under the Axumites, or the subsequent "Ehtiopian Empire" when western scholarship usually starts calling the Abyssinia. In between the Axumites and the so-called Solomonic Dynasty, was the Zagwe kingdom. They hardly controlled most of modern Ethiopia, but they had the core region around Axum and Lalibela in the highland. They were much more isolationist, partly because they were cut off. They no longer had access to the Nile, nor the coast to facilitate communication and trade and communication. They are mostly known from later chronicles, lacking in detail.
I can't find any record with a list of their titles to determine whether Ethiopia or Habashat (if either) was in more common use at the time."Ethiopia" was the standard by the 13th century, so that seems like the most likely option. | [
"It was preceded by a number of regions which were in Jewish rule in the north-west part of Ethiopia. The Jewish-Ethiopian tradition dates the establishment of the Kingdom of Semien to the fourth century, right after the kingdom of Axum turned to Christianity during the reign of Ezana of Axum.\n",
"In Greek histo... |
Are there any "dead" sports? Sports that were huge at one time but then stopped being played? | Chariot racing used to be very, very popular in the Roman and Byzantine empires. Here's a couple anecdotes:
* The highest-paid athlete in all of history was likely the charioteer [Gaius Appuleius Diocles](_URL_1_) (2nd century AD). He earned enough in his lifetime (about 15 billion in today's dollars) that he could have fed all of Rome for a year.
* During the reign of the Byzantine emperor Justinian (482-565), the supporters of the chariot teams, the Blues and the Greens, were so numerous that they were able to [threaten the stability of the empire during the Nika Riots](_URL_0_). Justinian allegedly nearly fled the empire in fear of the rioting fans, but his wife convinced him to stay and orchestrate a massacre of the partisans instead. 30,000 rioters (about 10% of Constantinople's population) were killed while gathered inside the Hippodrome, the capital's chariot-racing arena. | [
"Sudden death has a controversial history in association football. Important matches were traditionally resolved by replaying the entire match, however in the era of television and tight travel schedules this is often impracticable. Replays are still used in some major competitions (like the FA Cup).\n",
"The app... |
how does boltbus stay in business charging $1 fares? | The $1 tickets can be difficult to get sometimes, especially for high demand routes. If I want DC to NYC, I have to get that ticket around a month early. I think BoltBus strives on customers buying tickets within a closer window and paying full price. | [
"The MBTA gives a discount for CharlieCard users that began with the fare increase that took effect on January 1, 2007, and continuing with later increases. For example, a subway or trolley ride costs $2.10 with a CharlieCard but $2.65 with a CharlieTicket or cash. Local bus riders get a $0.50 discount with a Charl... |
Why do hot things burn us? | Hot things burn us because when we touch them or get near them they transfer some of their energy to us. That extra energy causes chemical reactions and damage to our skin.
Yes, some materials are better conductors or heat than others. Water will burn you faster than air. While porus rocks will burn you slowly, this is why "walking over hot coals" is possible. | [
"Solid objects that are hot can also cause contact burns, especially by children who intentionally touch things that they are unaware are too hot to touch. Such burns imprinted on the skin usually form a pattern that resembles the object. Sources of burns from solid objects include ashes and coal, irons, soldering ... |
Rules Roundtable VII: No Personal Anecdotes | This reminds me of the time when ... Oh. That's right. Never mind.
But seriously, it is terribly frustrating for me. I have been an observer of a great deal of history, and I have been a historian for so long, that my observations are not without context and self-reflection from previous decades. People ask about the Summer of Love or about how Baby Boomers reacted to news of the Tet Offensive in 1968 or of Kent State May 5,1970, and I find myself wanting to respond with an answer about how different the older BBs were/are from the younger counterparts (a point consistently missed on this sub!!!).
And I have been collecting jokes about presidents since Nixon's winter of 73/74 in the White House (it involves snow), but every time I see a question that involves something I can still remember vividly, I must resist the temptation to write not just "an answer" but "the answer."
And yet, ... this rule is a good one. Even my memory is not infallible and as I get older, "Fallible" has become my middle name (although I still remember the presidential jokes word-for-word!!!!). One personal anecdote allowed would open the floor gates. We need a subreddit called AskHistorianswhorememberreallyoldshit, but short of that, this is a good rule, and if I must live by it, all you young whippersnappers will just have to learn to deal with it. | [
"The story displays Wodehouse's excellent use of language and humor. It begins with the Oldest Member discussing people who lack the proper golfing spirit (\"I have known Bream to concede a hole for the almost frivolous reason that he had sliced his ball into a hornet's nest and was unwilling to play it from where ... |
What would a siege in pre-Columbian Mesoamerica have looked like? | You may be interested in this old comment of mine regarding siege warfare in the Late Post classic (i.e., Ye Older Azztek Times): _URL_0_ | [
"The Siege of Puebla occurred between 16 March and 17 May 1863 during the Second French intervention in Mexico, between forces of the Second French Empire and forces of the Second Federal Republic of Mexico. The French were advancing toward Mexico City, and were blocked by Mexican troops at Puebla.\n",
"The Siege... |
why isn't anything being done about the ddos attacks on psn and xbl? | You can't DDOS proof a server, thats why DDOSing is so effective, I bet microsoft and sony are doing their best to track down the attackers, after that they might deal with the hackers themselves (make them disappear) or alert the authorities which would result in prison time and really high fines. Hacker groups are really hard to track though thanks to the use of bots.
| [
"The goal of DoS L2 (possibly DDoS) attack is to cause a launching of a defense mechanism which blocks the network segment from which the attack originated. In case of distributed attack or IP header modification (that depends on the kind of security behavior) it will fully block the attacked network from the Inter... |
how does computer virtualization work hardware and software levels. | A physical PC is composed of various hardware bits presented to the OS by the BIOS. A hypervisor is a small piece of software that sits between the physical hardware and the virtual machines that *slices* up the physical hardware and presents smaller chunks of emulated hardware to these virtual machines. (i used the term emulated, but most modern hypervisors don't actually use emulation)
in a ideal world this would be a 1:1 ratio. If your host has 12 cpu cores and 48gbs of ram, you could have 5 virtual machines each with 2 cores and 8gbs of ram, leaving a bit left over for the host.
there are various "tiers" of hypervisor depending on how they are implemented but they all take physical resources and slice them up into virtual resources.
The more advanced hypervisors like ESX and Hyper-V enable sharing of these resources between multiple virtual machines simultaneously. In our scenario above, we could give each of our 5 VMs 4 cpu's and 10gb of memory each, even though we don't physically have that much. Most systems only use a fraction of their total resources, your PC right now may only be using 20% of your CPU and maybe half of your memory. Hypervisors can share these unused resources between virtual machines with higher needs.
Source: Software engineer specializing in Microsoft Hyper-V | [
"Computer virtualization refers to the abstraction of computer resources, such as the process of running two or more logical computer systems on one set of physical hardware. The concept originated with the IBM mainframe operating systems of the 1960s, but was commercialized for x86-compatible computers only in the... |
Was the Reichstag fire perpetrated by the NSDAP? | The general consensus among historians today is that the NSDAP was not responsible for the fire, but that they were preparing for some type of pretext to expand the emergency powers they already possessed. Several legal measures that greatly expanded the central government's power had already been instituted before the Reichstag Fire Decree. The emergency decree "For the Protection of the German People" of 4 February had granted the Chancellor the right to ban political parties, press organs, and lock up political opponents. Such decrees built on prior precedents in the 1930s when various central governments used the emergency powers of the constitution to curtail press freedoms and other political restrictions. The SA had already been elevated to the status of auxiliary police by 22 February. The Reichstag Fire Decree provided a capstone for removing most of the civil rights protected by the constitution, yet many of these rights were in the process of already being stripped away.
Richard J. Evans at the LRB has a good [book review essay](_URL_0_) explaining the mainstream historical opinion on the fire as well as the more heterodox historians who maintain the NSDAP was guilty of a conspiracy. | [
"The Reichstag fire (, ) was an arson attack on the Reichstag building, home of the German parliament in Berlin, on Monday 27 February 1933, precisely four weeks after Adolf Hitler was sworn in as Chancellor of Germany. Hitler's government stated that Marinus van der Lubbe, a Dutch council communist, was found near... |
what exactly is it that makes the noise of waves on the shore? | It's sound of millions of drops, bubbles and splashes of water hitting rocks, plus sound of billions rocks and sand particles colliding with each other as water moves them. Sound of waves hitting smooth concrete walls is noticeable quieter. And if water is still and just barely moves sand, you can hear faint noise of that sand moving, which is much closer to "gray noise", whilst usual waves hitting shores sound has much more distinctive ticks and hits and all that bubbling noise. | [
"A sound wave propagating underwater consists of alternating compressions and rarefactions of the water. These compressions and rarefactions are detected by a receiver, such as the human ear or a hydrophone, as changes in pressure. These waves may be man-made or naturally generated.\n",
"When surf on the lake is ... |
Why does applying heat to aching muscles help them, and the same question to applying cold to swollen areas? | I am not sure why heat helps aching muscles, however the cold helps deal with the problems of the inflammatory response. One of the conditions of the inflammatory response is vasodilation. Vasodilation means increased blood flow to the area, which causes the increase of heat, redness, et cetera.
Swollen areas are just areas undergoing inflammation. Applying something that is cold to said area helps mediate the symptoms of inflammation (reducing heat) and causing vasoconstriction (i.e. less blood flow - reduced symptoms of inflammation) | [
"Heat (thermotherapy) is usually applied at least 48–72 hours after the initial injury. It is used to improve blood flow and subsequently healing, and to increase extensibility of tissues. Improved blood flow can also encourage fluid reabsorption, which reduces swelling, and encourages phagocytic cells to enter the... |
how does free trade agreements protect local market? | Free trade agreements are the opposite of "protecting" local markets. A free trade agreement allows goods to cross borders untaxed, so that foreign goods and domestic goods can compete on a (somewhat) even field. If the domestic market can't compete, because it cannot produce as cheaply, then the domestic products will sell fewer units and lose money.
Protecting markets means adding tariffs or quotas to foreign goods to artificially raise their prices, so that the domestic goods are cheaper by comparison. | [
"The US - Middle East Free Trade Area (USMFTA) is expected to bring about new market access for U.S. consumer and industrial products; opportunities for farmers and ranchers; banks, insurance, securities; telecommunications; and e-commerce. The agreement also includes assurances for U.S. businesses in regards to co... |
Why aren't more things nuclear powered? | Economic issues are largely what prevent the use of nuclear propulsion aboard civilian ships, but there is also military motivation to avoid doing so as well. In the case of nuclear powered transport vehicles, naval reactors and related technology are highly classified. Even if intended for civilian uses, mini-reactors can easily be repurposed to run a military ship or sub, and so the technology is restricted in an attempt to control its proliferation to unfriendly nations.
There actually have been nuclear-powered merchant ships that were built as demonstrations. The [NS Savannah](_URL_0_) is one example. But between the economic costs, the need for expertly trained ship operators, military issues, issues of safety, decommissioning and waste disposal, having thousands of mobile reactors wandering the high seas is far more of a headache than it's worth. | [
"Nuclear power is a more exclusive form of energy storage, currently limited to large ships and submarines, mostly military. Nuclear energy can be released by a nuclear reactor, nuclear battery, or repeatedly detonating nuclear bombs. There have been two experiments with nuclear-powered aircraft, the Tupolev Tu-119... |
why is florida the site of most, if not all shuttle launches in the u.s? why not something with more consistent weather like arizona? | The higher rotation speed thing people are mentioning is true, but minor. Big reason is safety--we don't want launches to occur over land. Since all launches from Florida go east, they head over the Atlantic if anything goes wrong. The reason we have a launch facility at Vandenberg (CA) is because sun-synch launches from the Cape would mean flying over land.
Also, a big reason to launch from the equator in general is for GEO satellites. Yes, it takes a bit less fuel to actually get to orbit, but the latitude you launch from usually determines your inclination. Inclination change maneuvers are extremely expensive, so if you can launch into a 0 inclination orbit you can save a lot of fuel.
Edit: Just how minor is the rotational effect? [Less than one percent.](_URL_0_)
Edit 2: This blew up since I went to the bars. I'll try to respond as much as I can!
Edit 3: I'm going to bed. I'll try answer any other questions that come up in the morning. Otherwise, feel free to shoot me a PM and I'll do my best to answer. | [
"The National Aeronautics and Space Administration was forced to cut an environmental mission short in order to avoid the projected path of the hurricane, with the agency determining that the storm posed enough of a threat to their Extreme Environment Mission Operations near Key Largo, Florida. While Rina was weake... |
Everyone knows about Roman slavery, and the Transanlantic Slave Trade. But how about slavery in Medieval times? | Many enslaved women in the late medieval Mediterranean were forced into work as wet nurses. This is an excerpt from a longer article I wrote on wet nursing in Latin Europe:
For enslaved women forced to serve as wet nurses, the situation was even more demeaning than that of the municipal nurses. Since 1179, canon law had forbidden Christians from hiring Jews and Muslims to nurse their children (although the frequency of reiterations—from Christian and Jewish authorities alike—points to the frequently-informal shared breastfeeding duties among Christian and Jewish women neighbors). And yet from the thirteenth century into the early modern era, slaves in the Christian Mediterranean were almost always purchased or captured Muslims. To Christian parents, the solution was simple: forced baptism.
And even beyond this indignity, evidence concerning baptized Muslim wet nurses indicates the growing tendency to classify and judge people by skin color. The humour and heat imbalances in darker-skinned women made them bad mothers, according to medical authorities. And since wet nurses were understood as little more than biological appendages of real mothers, over and over, slave purchase and rental contracts demonstrate a keen preference for light-skinned baptizatae of nursing age.
Yes, rental contracts. Enslaved women pressed into service as wet nurses weren’t always just serving the family they at least knew and were comfortable with. Owners might hire out a *baptizata* as a nurse for some extra cash, or sell her altogether if the price was attractive enough.
And if no wet nurse was available? The brutal, systematic, and endemic sexual exploitation of enslaved women in Iberia could be—was—turned to economic use. When the foundling hospital of Perpignan was so financially overwhelmed in 1456 that it appealed to the city for extra money, the rectors made it bleedingly clear that aristocratic men bringing in their own bastard children were to blame. One man in 1400 Barcelona openly admitted sending away his own child so the baby's mother, an enslaved woman, would be free to nurse his legitimate heir.
And therein lay the cruelest blow of medieval wet nursing practice. Medical thought and popular religious teaching alike forbade women from nursing more than one child at the same time. All these wet nurses, all these “mothers who weren’t,” were mothers. They were mothers who weaned their children too early and quickly in order to make some money for the family; they were mothers who lost a child in infancy and had milk but no one suckle; they were mothers sold away from their newborns forever.
*(n.b. I'm super busy today so it will be a little while before I can get to follow-up questions if there are any; my apologies in advance for the delay.)* | [
"Roman slavery was not based on ideas of race. Slaves were drawn from all over Europe and the Mediterranean, including Gaul, Hispania, North Africa, Syria, Germany, Britannia, the Balkans, Greece, etc. Those from outside of Europe were predominantly of Greek descent, while the Jewish ones never fully assimilated in... |
how does the us government spending increase year after year when income and corporate tax rates have been dropping (based on charts found on google)? | The U.S. government has a budget deficit; it spends more than it takes in. It can continue to do so as long as people are willing to cheaply lend money to it by buying bonds, and U.S. bonds remain the standard safe investment on which the global financial system is based.
To more directly address your question, though, the relevant measure is how much the U.S. government earns and spends *as a percentage of GDP*. If the economy is growing, then tax rates can be lowered while keeping the same amount of revenue. (20% of $100 is $20, but so is 10% of $200.) The deficit as a percentage of GDP has been decreasing in recent years because of a strong recovery from the 2008-2009 financial crisis, see data from the [Federal Reserve Bank of St. Louis](_URL_0_). | [
"Many studies argue that tax changes of S corporations confound the statistics prior to 1990. However, even after these changes inflation-adjusted average after-tax income grew by 25% between 1996 and 2006 (the last year for which individual income tax data is publicly available). This average increase, however, ob... |
why do nfl teams claim they cannot survive without a brand new state of the art stadium? | New stadiums are good for business, so the owners want them. They try to convince taxpayers to fund the stadiums, because obviously that's better than paying for the stadiums themselves. So they try to convince taxpayers that existing stadiums are not usable. | [
"In the following years the stadium still wasn't considered as up-to-date as other NFL stadiums. Several reasons existed, including a lack of surround sound, smaller video boards compared to the rest of the league and poor cellular reception, among others. During the 2013 offseason, the Panthers renovated the home ... |
the friendship paradox. how can the average person's friends have more friends then them? | Imagine you have six people: Alice, Bob, Charlie, Dave, Eric, and Zorp. A-E are all friends with Zorp but not with each other. Zorp has 5 friends, all the others have 1. On average, each person's friend has more friends than them, because 5 have only one friend who has 5 friends. Only one person has friends with fewer friends.
Another way to think about it is that people with more friends are more likely to have you as a friend in the first place. | [
"BULLET::::- The friendship paradox is the phenomenon first observed by the sociologist Scott L. Feld in 1991 that most people have fewer friends than their friends have, on average. It can be explained as a form of sampling bias in which people with greater numbers of friends have an increased likelihood of being ... |
why won't the vacuum cleaner noise make me go deaf but listening to high volume music (which i can't hear over the vacuum cleaner noise) through earphones will? | If the vacuum cleaner noise is that loud it does have the chance to damage you hearing such that you go deaf. So I am not sure what you are basing you assumption on. | [
"Manufacturers of sound-masking devices recommend that the volume of white noise machines be initially set at a comfortable level, even if it does not provide the desired level of privacy. As the ear becomes accustomed to the new sound and learns to tune it out, the volume can be gradually increased to increase pri... |
Are there any conditions under which men can produce breast milk? | It is called Couvade Syndrome when a man experiences the same hormonal effects during pregnancy as women.
Actual lactation is also possible;
_URL_1_
Plus, a newborn's body is jam packed with their mother's hormones so some males are born with engorged breasts and lactating nipples known as "Witch's Milk" occur
_URL_0_ | [
"In breastfeeding women, low milk supply, also known as lactation insufficiency, insufficient milk syndrome, agalactia, agalactorrhea, hypogalactia or hypogalactorrhea, is the production of breast milk in daily volumes that do not fully meet the nutritional needs of her infant.\n",
"Low milk supply can be either ... |
how do those free movie streaming sites get all of those movies? | It's basically a big international "collective" of pirates who upload the content individually to multiple sites at the same time. | [
"Movies Anywhere is a United States-exclusive cloud-based digital locker and over-the-top streaming platform operated by The Walt Disney Company. The service allows users to stream and download purchased films, including digital copies redeemed from codes found in home video releases as well as digital purchases fr... |
Is it possible to reverse climate change quickly? | **Short version:** Just realised this has turned into an essay. The short version is that geoengineering would allow us to counteract some of the dangerous effects of climate change and in theory could act as an "emergency brake", but they have a huge number of serious side-effects so we should avoid being put into a situation where we have to use them. No form of geoengineering will allow us to reverse *all* of the impacts of climate change. Our best hope with geoengineering is Carbon Capture and Storage, but even that has issues.
--------------------------------------------------------
The simple answer is "No", it's not possible to revert back to the pre-industrial state quickly (or in remotely comparable time frames).
The more complicated answer is that there *are* ways of rapidly changing some aspects of the climate system to counteract the effect we've had, but this is not the same thing as returning back to the pre-industrial climate. You've probably heard of geoengineering, it's turning into a buzzword these days and a lot of people seem to be hailing it as some kind of saviour for humanity. At first glance, geoengineering looks pretty great - some proposed projects such as solar radiation management using aerosols promise to rapidly reduce temperatures to a point where we'd be back to pre-industrial temperatures in a few years. There's actually a lot of truth to this too - it's basically mimicking the effect that large volcanic eruptions have on the climate since the sulphate aerosols they release into the atmosphere reflect a lot of the incoming solar radiation (hence the name solar radiation management) reducing the amount of heat reaching the earth's surface and thus reducing the earth's temperature. Indeed, it's probably true that SRM is the only vaguely economical way of rapidly reducing the earth's temperature. Unfortunately, there are many, *many* problems. Focusing on SRM for the moment, first of all, it doesn't tackle the root cause of the problem. CO2 and other greenhouse gasses are still accumulating in the atmosphere which means the moment you stop using SRM, the temperature will *skyrocket* because the aerosols have a fairly short life. Once you start using SRM, the entire planet is basically forced to continue using it until GHG concentrations have fallen back to pre-industrial levels, which would take an extremely long time without specific intervention. If anything interfered with our SRM program and for whatever reason we didn't replenish the aerosols fast enough, we've got an instant global catastrophe on our hands. On a similar note, since SRM doesn't deal with CO2 accumulation in the atmosphere, it doesn't deal with the "other CO2 problem", namely ocean acidification. This doesn't get nearly as much attention as climate change but it is already having serious effects on aquatic life and it could cause a tremendous amount of economic and social damage in the problem. In fact, SRM will make ocean acidification worse because the aerosols that will probably be used are acidic. It gets worse, because whilst we understand the basic physics behind SRM, because of the complexity of the climate system, it's impossible to predict precisely what would happen. Most of the models we have at the moment predict that it would bring down temperatures [(there's quite a decent discussion in this TED talk here)](_URL_0_) but they also predicts major changes in weather systems. For instance, many drought-prone areas today would likely become even more drought-prone with SRM. From the models we have today, it's likely that the wealthier, better-off countries would do okay-ish with SRM but the poorer regions which already suffer from difficult climates would have serious, serious problems.
As I mentioned, SRM does nothing about ocean acidification, which raises the important point that no single geoengineering technology can tackle all of the effects of climate change, but the more geoengineering technologies you implement, the more side-effects you're going to get and the more reliant the entire planet will become on human climatic intervention. If we start using geoengineering, that's basically the same as putting the planet on a man-made life support machine (I think that analogy is from that TED talk). *To make matters worse*, there's an additional sociological problem too. The scientifically literate will probably understand that geoengineering, if it is to be used at all, should only be used as an absolute last resort but this is unlikely to be communicated properly to decision-makers and the public. It doesn't take a lot of difficulty to imagine the headlines if SRM were properly developed: "Scientists develop cure to climate change!". Obviously, no geoengineering strategy is going to reverse what we've done to the planet so far, it will only "reverse" certain changes in return for some pretty major side-effects, but that probably won't be acknowledged by the public. We've already got a ridiculous amount of paralysis in dealing with climate change, that's why we're in the position of considering geoengineering in the first place, and the moral hazard of having a technology like geoengineering will only make us more paralysed and more likely to have to rely on these dangerous technologies.
On the other hand, it's possible that the side-effects of geoengineering could be less serious than the effects of catastrophic climate change if we continue to screw up. So the question is, do we develop it as an emergency measure in case we mess up big-time, thus increasing the *likelihood* that we mess up, or do we refuse to develop geoengineering but potentially lose out on the only emergency brake we have? It's an incredibly hard question to answer because on the one hand, the side-effects of geoengineering will be very serious and it will punish the less well-off disproportionately (and simply having the technology available will increase the likelihood that we'll have to resort to it), as well as basically being an open admission that we've failed the planet but on the other hand, it's hard not to get the impression that it might be necessary. At the moment, we're continuing to fail spectacularly at dealing with climate change, despite the occasional motivational stories you hear from time to time, and we're heading towards a genuine climate catastrophe. If we do start to think seriously about geoengineering, those discussions *have to be impartial*. At the moment, a lot of large energy corporations are starting to get interested in geoengineering (particularly CCS, I'll discuss that in a moment) because it essentially gives them a license to carry on polluting and naturally, the funding for geoengineering will probably come from governments rather than those corporations. This really is one of my biggest concerns with developing geoengineering and the simple fact that it's unlikely we'll be able to stop profit-driven organisations from leading the geoengineering debate makes me very reluctant to support geoengineering development.
A final note - I've been mainly discussing more extreme forms of geoengineering here. Carbon Capture and Storage (CCS) can be counted as a form of geoengineering and it essentially consists of removing carbon dioxide from fuels before you burn it (you end up burning a mixture of hydrogen and some other gasses) and the carbon dioxide is then permanently disposed of, either in the ground, in artificial mineral sponges or potentially used as chemical feedstock. Contrary to things like SRM and ocean fertilisation, CCS is "soft" in the sense that it doesn't directly change the energy balance or chemistry of the environment. It's simply a way of allowing us to reduce our carbon emissions whilst allowing us to continue burning fossil fuels. It's an unfortunate fact that there simply isn't the political will to shift away from fossil fuels quickly enough so, accepting that, CCS gives us a more establishment-friendly method of rapidly reducing our carbon emissions whilst not forcing us to reduce our reliance on fossil fuels. Also, contrary to the other forms of geoengineering I mentioned, CCS is actually tried and tested. You can even take it further with Bio-Energy with Carbon Capture and Storage (BECCS) which is like ordinary bio-energy but rather than burning the plants at the end (thus making it *hypothetically* carbon neutral), you put the biomass through a CCS process which actually makes it carbon-negative, that is it removes carbon dioxide from the atmosphere. BECCS is basically our only way of getting CO2 out of the atmosphere and thus tackling the root cause of the problem but BECCS is *way* too expensive and inconvenient at the moment do be done on a large scale so this almost certainly will not be a global solution. Nevertheless, we still have ordinary CCS which works. The main issue with CCS is that it's a half-solution. Yes, it's better than the status quo but it's nowhere near as good as actually switching to a truly sustainable energy infrastructure. It's a solution that's very favourable to the large energy corporations (which makes it quite a politically good solution too, since these corporations wield a lot of influence over governments) and it basically allows us to continue with business-as-usual whilst reducing the risks of an environmental catastrophe. And once again, you've got the moral hazard problem. Personally, I think the switch away from MNC-dominated centralised energy gives us a great opportunity to tackle many of the social and political problems that plague our society and CCS obviously completely blocks that, but you could also view it as the best option that's realistically available to us given the constraints we have. I'd rather not have to get into geoengineering in the first place but if it's politically necessary, CCS is probably our best shot. | [
"Whether the initial forcing mechanism is internal or external, the response of the climate system might be fast (e.g., a sudden cooling due to airborne volcanic ash reflecting sunlight), slow (e.g. thermal expansion of warming ocean water), or a combination (e.g., sudden loss of albedo in the Arctic Ocean as sea i... |
At what point did 'chroniclers' become 'historians' and what is the difference? | A Chronicler and Historian are two very different job descriptions and we still have both working today, though in different forms from the past.
A chronicler primarily compiled current information into a written timeline. This information was often of local import and didn't contain analysis or research. Think of it as a book of current 'facts' as written down by the people who where alive when it happened. Some facts could be word of mouth or even fantasy, but it was basically stuff collected by people who experienced it. This timeline would be copie and sent to other places where each copy would be independently updated. This means a chronicles or annals could be the same up until a certain point and then have different facts added to them over time. The [Anglo-Saxon Chronicle](_URL_0_) is a great example of a 'living' document of this nature.
Historians study the past, analyze it, compile it, synthesize it and come to conclusions based on their findings. One does not need to have lived though an event to be a historian of it.
In today's day and age you could say that newspapers, google and bloggers are the chroniclers of our time. Historians will look at that collection of 'facts' and analyze it.
A TL;dr could say that chroniclers compile the information and historians study it. | [
"Chronicles are the predecessors of modern \"time lines\" rather than analytical histories. They represent accounts, in prose or verse, of local or distant events over a considerable period of time, both the lifetime of the individual chronicler and often those of several subsequent continuators. If the chronicles ... |
why is a pin number considered safe with 4 numbers while a password needs 8 chars with numbers and capitals? | Because anyone on the internet can have a go and guessing my username and password, often an unrestricted number of times. Only people with access to my PC or my credit card can guess my PIN, and usually only 3 to 5 times. | [
"BULLET::::3. A 14-character password is broken into 7+7 characters and the hash is calculated for the two halves separately. This way of calculating the hash makes it exponentially easier to crack, as the attacker needs to brute force 7 characters twice instead of 14 characters. This makes the effective strength o... |
WW2 Tactics and Doctrine Innovations of the Allies | Goodness me, this is quite the topic to tackle, and I'm afraid rather beyond my abilities to cast my net both widely and deeply. I can however, offer some information regarding my own research niches, namely British armoured doctrine, and also the North African Campaign, and perhaps some of the other historians on here may offer their insight into other topics.
So, to begin, we must first make a cursory survey of British armoured doctrine at the outbreak of the war, its development through the interwar itself an interesting and complex topic. The role of the tank in British doctrine at the start of the war was largely envisioned as a 'cavalry' one; the provision of reconnaissance and screening elements for their parent divisions, as well as serving as flank support, covering the vulnerable wings of the main body of the army, and harassing enemy formations to prevent their effective deployment. This was largely a product of wider British doctrine, which established the infantry as the central axis of the army around which all other units pivoted, the influence of the so-called 'Tank Corps Radicals', who argued for the primacy and power of the tank as an independent weapon, and the restrictive and rigid structure of the interwar army, which had seen the cavalry converted to tanks rather than the Tank Corps expanded. This had a number of interesting consequences for the structure of British armour, the most prominent of these being a bifurcation in British tank design - due to the demands for both a mobile, wide-ranging cavalry-style tank, and an infantry support weapon similar to the first World War, British tank forces were hence largely split into army tank battalions and divisional cavalry, the former for infantry support, the latter for recon and flank cover. Thus, Britain's tank forces were relatively unconcentrated, usually referred to as being 'penny-packeted' among the rest of the army, with the exception of the 1st and 7th Armoured Divisions, the two great interwar experiments with concentrated armoured forces.
So from this start, how did Britain innovate with regards to armour? To begin with, very little; the 1940 campaign in France and the Low Countries, though disastrously highlighting the shortcomings of much of Britain's armour, which was undergunned, under-armoured, outdated, and mishandled, was largely overshadowed by the wider disaster of the campaign in general. What changes to the organisation of armour were suggested were rejected, in part, French suggests, because they were seen to be copying the Germans. Moreover, this failure to adapt doctrine was accompanied by a more serious crisis of tank production, as the BEF had brought only 13 tanks home with them from France, of an original number of over 700. In order to combat these desperate shortages, British tank production continued to churn out existing models of tank, many of them already outdated, setting back the already sluggish development of more modern tanks.
If the French campaign failed to overturn the pseudo-cavalry doctrine of British armour, the early phases of the North African campaign was in some ways to entrench it. 7th Armoured Division, as part of General Richard O'Connor's Western Desert Force, inflicted a series of punishing defeats on the Italians from December 1940, manoeuvring in precisely the sort of cavalry strike role that British doctrine envisioned. This was not to last, as where these tactics had worked against Graziani's poorly-equipped, unmotivated Italian 10th Army, they foundered against the newly arrived Afrika Korps in 1941. Outmatched in armour, and with Rommel utilising a mixture of tanks and anti-guns in his formations, British armour failed to find success.
The good news about lack of British success with tanks against Rommel was that this prompted change. Unfortunately, the British initially perceived the problem as the solution; the mobility and striking power of German tank units encouraged 8th Army (the former western desert force) to try similar tactics, creating the 'Jock columns', small brigade groups of units intended to strike from unexpected points and retreat. Unfortunately, what the British had failed to grasp was the need for combined arms coordination between these small groups, and consequently, they were hugely ineffective.
Nevertheless, following Operation Crusader in Nov.41, the British slowly reformed their armoured doctrine. Manoeuvre was emphasised less in a tactical sense, firing on the move largely abandoned, and a significant emphasis was placed on use of terrain, force concentration and firepower, the latter in particular being aided by significant improvements in allied tank design, notably the Cruiser _URL_0_ Crusader and the M3 and M4 medium tanks. Additional emphasis was placed on all-arms cooperation - tanks, infantry, artillery, and other branches could and would cooperate with each other, a notion underwritten by the addition of integral motorised infantry and artillery to armoured divisions, thus re-balancing them away from the 'all-tank' concept championed by the RTC in the 1930s.
Refinements to British armoured doctrine paid dividends, even during the disastrous Battle of Gazala in May 1942. The 10th Hussars, partnered with 11th RHA, smashed through a line of German anti-tank guns on the 28th, aided in no small part by the smoke screen and suppression fire of the horse artillery.
The steady improvement of the performance of British tank units was further spurred by the arrival of Bernard Montgomery in August 1942, not from radical reform, but by insistence on training, regimes of which had largely been neglected as most units were desperately needed on the frontline. Monty summarised it thus: ‘although the Eighth Army was composed of magnificent material it was untrained; it had done much fighting, but little training’. Monty also was a driving force behind the eventual reunification of the 'cruiser' and 'infantry' tank concepts with his suggestion of a 'universal tank' - in effect, an MBT, which was largely reflected in his willingness to adopt the Sherman, and later Cromwell, as both infantry support tanks and mobile weapons in their own right.
Although I somewhat oversimplifying, the pattern of an increasing emphasis on cooperation and flexibility in British armour can largely be seen for the remainder of the conflict. Tunisia, Italy and Normandy all placed a far higher premium on infantry/armour/artillery cooperation than before, and this was reflected in the frequency with which infantry units were 'paired' with an armoured regiment for mutual assistance. Thus, despite misfires, such as Operation Goodwood, or the assault on Coriano, and the almost mythological perception of German technical superiority in tanks, British armoured doctrine evolved consistently throughout the war into a functional, if not perfect, series of operational concepts, and bound together by a culture of flexibility, largely enabled by the loose centralisation of British regiments at that point, which enabled innovation and adaptation to meet changing circumstances.
I hope this short summation of some of my own work has been of interest to you, if a tad brief (it is in part a very foreshortened rundown of one of my theses), and I'm more than happy to point you in the direction of interesting literature on the topic if you would like. | [
"Breakthrough tactics were later to play a large role in the early German blitzkrieg offensives of World War II and the later attacks by the Soviet Union and the Western Allies to defeat Germany, and evolved into modern armoured warfare.\n",
"World War I strategy was dominated by the \"Spirit of the Offensive\", ... |
Why didn't the Confederate Army just attack Washington D.C. in 1863, and tried to end the war right then and there by forcing Lincoln to surrender? | In short, because there was an opposing army trying to prevent them from doing so. In 1862 Lee had moved into MAryland in the hope of isolating Washington, cutting it off from the rest of the Union even if not taking the city itself, so as to apply presure for a negotiated end to the conflict, but failed after being beaten back at Antietam.
And as to your exact question, the Confederacy *did* make an attempt in 1863, marching North into Pennsylvania, where they encountered the Union Army at Gettysburg. Had Meade and the Army of the Potomac failed, well, we can only speculate what the next phase of the campaign would have looked like, but it is quite possible that the Army of Northern Virginia would have attempted to press South to threaten Washington, although whether they would have taken the city itself, or simply cut off lines of communication to isolate it, we don't know as history went another way.
And finally in 1864, a small Confederate force under Jubal Early did actually ride up to the border of the city, engaging Union forces at Fort Stevens, although the intention was less to *capture* the city than to make it feel threatened and hopefully relieve pressure further South as Grant detached forces to go bolster the city's defenses.
To be sure, you're right that the Confederacy recognized the symbolism of Washington, and the disastrous blow to Northern morale that its fall or isolation would herald, which is precisely why they launched several campaigns over the course of the war which intended to present the threat of that possibility to the Union, but over several attempts, they were continually stymied by the Union Army.
This kind of stuff is covered in a basic history such as McPherson's *Battle Cry of Freedom*, although there are several books specifically about the defenses around the city, such as *Lincoln's Citadel* by Kenneth J. Winkle which comes immediately to mind. | [
"In April 1861, shortly after the Civil War began with the bombardment of Fort Sumter by rebel forces, Walker predicted that Washington, D.C. and Boston would fall to the Confederacy before May 1 of that year. However, this never happened, and the last time that General Robert E. Lee's army ever invaded the North w... |
Do the mantle, inner, or outer cores experience tidal effects? If not, why not? And, if so, why don't we constant volcanic eruptions? | Yes the entire Earth experiences tidal effects in one form or another. Since we are on a telluric planet the effects are not the same everywhere.
& nbsp;
The mantle is convective but on a timescale much longer than the orbital period of the Moon. This means the response to the tidal potential is an elastic one. This is just a large scale deformation of the mantle region (the standard equilibrium tide that results in the tidal deformation or bulge). This deformation will be dissipated and hence generate heat but this is a small amount of the total tidal energy dissipated through the Earth. As such it has a negligible effect on the mantle and crust of the Earth other than acting as a large scale deformation.
& nbsp;
The inner core is meant to be solid and the tidal effects on this would be similar to that of the mantle. I do not know of any research into the effects of tides on the solid cores as I believe most people think there is not much of interest to be found from this work.
& nbsp;
The outer core is however interesting! The outer core is convective on a much shorter timescale than the mantle but still considerably longer than the orbital period of the Moon. Further because this region is fluid it behaves as a visco-elastic fluid and hence has an elastic response (similar to the mantle) and a viscous response (which is an eddy viscosity from the interactions between the tidally excited flow and the convectively driven flow). If we consider the large scale deformation, as before, then we would expect that there would not be much dissipation in the system due to the orbital period being much shorter than the timescale for convection. Because of this the eddy viscosity will be very low and unlikely to play much of a role.
& nbsp;
However there is also the dynamical tide. That is the excitation of inertial waves. These are waves that are excited by the tidal forcing and balanced by the rotation of the planet. These waves will also be dissipated and act as a source of dissipation in the system. The dynamical tide is quite complicated! The bottom line is it has a role to play in tidally heating the outer core. It is possible and still an active area of research that the dynamical tide plays an important role in the geodynamo.
& nbsp;
From observations the majority of the tidal energy is dissipated in the oceans. But that does not mean these effects (such as in the outer core) are not important. | [
"Mantle convection causes tectonic plates to move around the Earth's surface. It seems to have been much more active during the Hadean period, resulting in gravitational sorting of heavier molten iron, nickel, and sulphides to the core and lighter silicate minerals to the mantle.\n",
"Reconstructions of seismic w... |
- with both options made available through evolution, how does the human body prefer/naturally choose how we breathe - through the nose or mouth? | The nose tends to prevent bacteria and other stuff from getting into your [body](_URL_0_). Seems like a solid choice. | [
"Human infants are sometimes considered obligate nasal breathers, but generally speaking healthy humans may breathe through their nose, their mouth, or both. During rest, breathing through the nose is common for most individuals. Breathing through both nose and mouth during exercise is also normal, a behavioral ada... |
Can Alzheimer's patients form new memories that they recall better than old memories? | You are correct, Alzheimer's is characterized by a primary anterograde memory impairment, while retrograde memory remains more stable until the latter stages of the disease. | [
"Amnesiacs with poor ability to form permanent long-term memories do not show a primacy effect, but do show a recency effect if recall comes immediately after study. People with Alzheimer's disease exhibit a reduced primacy effect but do not produce a recency effect in recall.\n",
"Memory distortion in Alzheimer'... |
why wasn't there a nuclear war between the soviet union and the u.s? | Because they BOTH knew to start a nuclear war would be DUMB.
Problem is some idiot will start one some day. | [
"In August 1949 the Soviets tested their first nuclear weapon, thereby escalating the risk of warfare. The threat of mutually assured destruction however, prevented both powers from nuclear war, and resulted in proxy wars, especially in Korea and Vietnam, in which the two sides did not directly confront each other.... |
How quickly does boiling water sterilize a surface? | Disclaimer: Don't take any medical advice from reddit, and yes this kind of counts because you made it relevant to yourself. However I'll explain because it's telling you not to.
A common sterilisation technique used in science is autoclaving which involves steam at around 120C for around 20 minutes to sterilise glassware. So no, stirring boiling pasta water will not truly sterilise your fork. It will *probably* kill *most* bacteria. Although there are also endospores which are still perfectly happy at boiling temperatures, and there are also bacteria that are happy up to 80C (Thermus aquaticus). USE SEPARATE UTENSILS IT ISN'T THAT HARD. | [
"Heating an article is one of the earliest forms of sterilization practiced. Moist heat sterilization processes sterilize using hot air that is heavily laden with water vapor, which plays the most important role in the sterilization. Boiling a sample for 30 minutes or more will kill virtually all vegetative cells p... |
how is money released into the economy. | Contrary to popular belief, the government actually *printing* money doesn't really impact the economy much at all. Nor does the government simply give money away. Money is primarily created through banks lending it to other people.
When you get paid by your job, do they pay you in cash? Of course not. They give you a check (or direct deposit) So now your job just paid you, say, $1000. What do you do with your check? Carry it around? No, you put it in a bank. So now you deposit your $1,000 into your bank account. You have $1,000.
Of course, the bank has 100 customers, each with $1,000 in their accounts. What does the bank do with that $100,000? They loan it out to someone. So they find someone who wants to buy, say, a $100,000 house, and this person put down 10%, so the bank loans them $90,000.
Now this homeowner pays off the old owner of the house with his $90,000 check, so what does *that* guy do? Does he wander around with $90,000 in cash? Of course not. He deposits it in *his* bank account.
So now:
* You & your friends have $100,000 in your accounts
* The old homeowner has $90,000 in his account
Total amount of money in the economy now? **$190,000**
Let's do it again. The old homeowner's bank loans out $81,000 to another guy to buy a house. The old owner takes the $81,000 and puts it in **his** bank. Now:
* You & your friends: $100,000 in your accounts
* The first old homeowner: $90,000 in his account
* The second old homeowner: $81,000 in his account
Total amount of money in the economy? **$271,000**
Lather, rinse, repeat: That's how banks create money in the economy. Now that you know that, you can understand what the *Federal Reserve Bank* does.
The Federal Reserve (putatively) controls how fast this money is created by controlling the interest rates they charge local private banks. Banks are required to keep 10% of the money they have out on loans available in cash.++ (That's where I came up with that 90% multiplier.) But they can make up temporary shortfalls by borrowing directly from each other, or the Federal Reserve. They pay one interest rate for borrowing from each other, and a slightly higher one for borrowing directly from the Federal Reserve. These are known as the *Federal Funds Rate* and the *Discount Rate*, respectively.
The Federal Reserve directly controls the Discount Rate and indirectly controls the Federal Funds Rate, and these two interest rates which impact how aggressively banks can make loans. The higher those rates, the more it costs banks to borrow money to cover the loans they have out. This is a very fine-grained, gentle way to stimulate or reign in economic growth. When the Fed decides the economy is going too slow, it lowers rates. When it decides it's heating up (read: *inflation*) it'll raise the rates. | [
"The circulation of money is first initiated by the transformation of a commodity into money. The commodity is taken from its natural state and transformed into its monetary state. When this happens, the commodity \"falls out of circulation into consumption\". The previous commodity now in its monetary form replace... |
I read that there is a class of stars called brown dwarfs. They have very low temperature and not enough mass to undergo hydrogen fusion. Why are they considered stars and not gas planets? | The distinction isn't a sharp one, but generally they're considered brown dwarves if they're hot enough to fuse deuterium but not hot enough to fuse hydrogen.
To quote my friend Dr. Wikipedia:
> Currently there is some debate concerning what criterion to use for defining the separation between a brown dwarf and a giant planet | [
"Protostars with masses less than roughly never reach temperatures high enough for nuclear fusion of hydrogen to begin. These are known as brown dwarfs. The International Astronomical Union defines brown dwarfs as stars massive enough to fuse deuterium at some point in their lives (13 Jupiter masses (), 2.5 × 10 kg... |
Based on the latest XKCD strip 'The Pace of Modern Life': did other civilisations and societies also have the notion that their current life was too fast paced? | Roman poets for example liked to praise the calm, tranquil pace and simple pleasures of rural life. Think the Eclogas of Ovidius (Ovid in English) and similar bucolic works. _URL_0_ So for them, city life was too fast paced, chaotic, materialist etc.
Now, the point is, we live in an age of urbanization, people flock to cities, our past was more rural, so this related. It is typically city life only that is called to fast paced. Oh and yes, a Golden Age in a past is also a main element of bucolic poetry... | [
"A montage follows, showing decades of technological progress, beginning with Cabal explaining plans for global consolidation by Wings Over the World. By 2036, mankind lives in modern underground cities, including the new Everytown. Civilisation is at last devoted to peace and scientific progress.\n",
"In conside... |
what does a computer do when starting up and how can this process be slowed down? | Your operating system is just a large program. Have you noticed that when you open a bunch of programs at once, it slows down a little? When your computer starts up, it needs to open a bunch of little programs at once. There are 2 categories: windows programs and your programs. Windows programs are things like; your display, hard drive, desktop and all the little things that make your computer work. However, you cannot change these. These windows programs are essential for your computer to work.
The ones you can change are your programs. You have start up programs, and these can really effect your power up time. Some of these are; updating processes, those icons next to your clock in the bottom left corner and all of the programs that open when your desktop comes up. What you need to do is get rid of all the things you don't need immediately when you log in.
A good program is Ccleaner. Download it and go to google for a good guide on what to remove.
Message me if your need more help.
Sources: IT and programming | [
"A user can terminate a program by invoking the key combination or . Pressing or any printing character on the keyboard suspends the console output. Output may be resumed by pressing the key (to delete all of the input) or by pressing (which will cause the input to be processed as a command as soon as the current c... |
Do our lungs, being a warm, moist spongy material in a dark cavity, have to constantly fight off mold, mildew, and other similar growths? | Most tissues in our bodies would facilitate growth of microorganisms were it not for our immune system. We spend a tremendous amount of energy making sure our cells have enough glucose/fats/proteins, a nice and pH-neutral environment in addition to a host of other accomodating factors. Many other microorganisms also thrive in such environments. So, yes, our body has several defense mechanisms in place to prevent fungal infections (and infections in general) of the lungs:
* Most particles the size of a fungus would get stuck in the upper-to-mid airways due to the physical shape of the airways
* The airways are lined with proteins that are either toxic to foreign microorganisms or bind chemicals essential to the survival of the microorganisms
* The epithelial cells of the airways constantly move and push foreign matter upwards towards the mouth and nose. If bigger things get caught, and these will often have some microorganisms on the surface, we cough them out.
* The airways are also lined with mucus that contains antibodies that will disable, kill or tag microorganisms for destruction.
* The alveoles of the lung have cells called macrophages that will literally eat any foreign cell they can fit inside themselves.
In addition to all of this, if the local defenses can't deal with the infection, they will send chemical distress signals and "call in the artillery". The rest of the immune system and the complement system will mobilize and eat, kill, starve or eliminate the infectious microorganisms through other mechanisms. | [
"Mold exposure has a variety of health effects, and sensitivity to mold varies. Exposure to mold may cause throat irritation, nasal stuffiness, eye irritation, cough and wheezing and skin irritation in some cases. Exposure to mold may heighten sensitivity, depending on the time and nature of exposure. People with c... |
what exactly is happening when an isp sends a refresh signal to your modem? why does it sometimes improve the connection speed? | Over time, the modems at both your end and the ISP end react to noise on the line by slowing down to maintain a stable connection. Resetting the calibration settings on a noisy line can temporarily make the speed faster when it goes back to the default starting speed, but the speed will just decrease again if the underlying reason for the poor line conditions isn't resolved.
This is an issue with both Cable and DSL connections, but is more pronounced with DSL, especially if the modem isn't kept powered on continuously for 10 days when the line is first installed (or subsequently reset). | [
"However, the telephone system introduces a small delay known as \"latency\" that interferes with this process. Even if the receiver sends the ACK immediately, the delay in the phone lines means there will always be some time before the sender receives it and sends the next packet. As modem speeds increase, this de... |
Do humans permanently retain some portion of the water they consume or is all of the consumed water eventually lost/replaced? | The other thing to consider is that water molecules are constantly being created and destroyed by chemistry. Proteins and other large molecules are hydrolysed (cut by water) where the H2O becomes an OH that leaves on one molecule and the H leaves on another. Similarly, building up new versions of proteins, etc creates 'new' water molecules that may have come from the atoms of things you ate, or oxygen that you breathe in. | [
"A human being can survive an average of three to five days without the intake of water. The issues presented by the need for water dictate that unnecessary water loss by perspiration be avoided in survival situations. The need for water increases with exercise.Since the human body is composed of up to 78% water, i... |
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