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Some questions about the common cold | While we're on the topic, is it true that pretty much all physical symptoms of a cold are in fact consequences of the body's immune response to it? And as an extension, the severity of the symptoms is not a measure of how serious the cold virus itself is, but a measure of the aggressiveness of the immune system's respo... | [
"While the cause of the common cold has only been identified since the 1950s, the disease has been with humanity throughout history. Its symptoms and treatment are described in the Egyptian Ebers papyrus, the oldest existing medical text, written before the 16th century BCE. The name \"cold\" came into use in the 1... |
why does computer memory capacity increase in multiples of 2? | They actually increase by powers of 2. | [
"During this same period, semiconductor memories were rapidly increasing in size and decreasing in cost. However, they were not improving in speed at the same rate. This meant the time needed to access data from memory was growing in \"relative\" terms in comparison to the speed of the CPUs. This argued for the inc... |
why are our legs inverted compared to our arms or others animals legs ? | Look at a dog.
It may look like it has a backwards knee, but it doesn't. The knee is much higher than you think. What you think is a knee is actually the ankle, because the dog is a digitigrade ("finger walker"), and could be considered to always be walking on tippy toes (though shaped to be many times more efficient)... | [
"Animals that are bilaterally symmetric have reflection symmetry in the sagittal plane, which divides the body vertically into left and right halves, with one of each sense organ and limb pair on either side. Most animals are bilaterally symmetric, likely because this supports forward movement and streamlining.\n",... |
why does a baseball traveling towards you fly farther when hit than a stationary one? | When the baseball is thrown towards you it has a certain amount of kinetic energy. When that ball hits the bat it transfers the kinetic energy into the bat. But, the bat doesn't simply absorb all of that energy. Most of it is reflected back into the ball. So, that reflected energy is added to the amount from the swing ... | [
"If a projectile, such as a baseball or cricket ball, travels in a parabolic path, with negligible air resistance, and if a player is positioned so as to catch it as it descends, he sees its angle of elevation increasing continuously throughout its flight. The tangent of the angle of elevation is proportional to th... |
how is the tissue folded to perfectly fit the box? | By a robot.
Tissue comes off the roller as one long stream, and is then cut into squares. These squares are offset on the conveyor belt, which then drops them into a stacker half-by-half. Once a complete stack is created, the box is slid over the stack from the side and the flaps are glued down. | [
"The large staples found on corrugated cardboard boxes have folded legs, but they are applied from the outside and do not use an anvil; jaw-like appendages push through the cardboard alongside the legs and bend them from the outside.\n",
"Cord lining contains both Epithelial (EpSCs) and Mesenchymal stem cells (MS... |
the obamacare birth control mandate. | Put in place by the US government to force health insurance providers/employers to include different methods of birth control on their employees plans at no cost to the employee. It stated that the mandate required all health plans to cover all contraceptives approved by the FDA. It covers pretty well anything you can ... | [
"After suing the Obama administration over the restricted access to birth control, in June 2013 the U.S. Department of Justice ordered that the Obama administration make all forms of emergency contraception available over the counter and without an age restriction.\n",
"For such companies, the Court's majority di... |
What were Octavian's prospects before Caesar's assassination? | At the time, Caesar's heir was a position without precedent. Caesar, alongside his peers Pompey and Crassus, had accumulated unprecedented degrees of wealth, power, and clients. The person who inherited Caesar's name inherited the power to move the Roman world, from client kings and ennobled senators down to the lowest... | [
"After the assassination, Marcus Antonius (Mark Antony) formed an alliance with Caesar's adopted son and great-nephew, Gaius Octavianus (Octavian), along with Marcus Lepidus. Known as the Second Triumvirate, they held powers that were nearly identical to the powers that Caesar had held under his constitution. As su... |
Did Nazi Germany ever attempt or plan to diplomatically annex the Japanese territories in the Pacific which used to belong to the German Empire? | No. In fact there was a treaty signed to the fact that after the war was over Japan and Germany were to enter negotiations and Japan was to pay Germany and Germany would formally hand them over.
Source Bernd Martin - Japan and Germany in the Modern World. | [
"Japan, allied with the Entente Powers during World War I, seized all of Germany's colonial possessions in East Asia and Micronesia, including the Northern Mariana Islands, and held them through the end of the War. Under the terms of the Treaty of Versailles in 1919, Germany was stripped of all her colonies worldwi... |
how do the openers on soda cans keep the can from cutting you when you drink from it? | The metal on the lip is beveled as part of the manufacturing process. That section also contains more of some element (i think molybdenum?) That allows the removed section to not shear off but rather detach under force. | [
"While beverage cans or cans of fluid such as broth can merely be punctured to remove the product, solid or semisolid contents require removing one end of the can. This can be accomplished with a heavy knife or other sharp tool—but can openers are much more convenient.\n",
"To shotgun a beverage, a small hole is ... |
why is the moon bright some nights, but other nights it's not as bright? | If you mean general brightness, outside of the cycles of the moon, crescent, half, full and so on, you know just one night you think it's a lot brighter than the next, that's most likely just due to high thin cloud level, and general haze in the atmosphere. This is the sort of thing that makes the day seem very, well, ... | [
"The Moon has an exceptionally low albedo, giving it a reflectance that is slightly brighter than that of worn asphalt. Despite this, it is the brightest object in the sky after the Sun. This is due partly to the brightness enhancement of the opposition surge; the Moon at quarter phase is only one-tenth as bright, ... |
what's the difference between an empty set and 0? | The empty set contains nothing. It's not a number, it's a group of 0 things.
0 is a number. | [
"In some textbooks and popularizations, the empty set is referred to as the \"null set\". However \"null set\" is a distinct notion within the context of measure theory. In that setting, it describes a set of measure zero; such a set is not necessarily empty. The empty set may also be called the \"void set\". Commo... |
what are lagrange points and how do they work? | It's 1am here so this might be a little oversimplified and weird; lagrange points are points in space where gravity of different celestial objects cancel out. You might know that larger masses cause a larger gravitational pull. Also, gravitational pull is quadratically inverse to distance, meaning the further away you ... | [
"In astronomy, Lagrangian points are five positions in the orbital plane of two large orbiting bodies where a small object affected only by gravity can maintain a stable position relative to the two large bodies. The first three Lagrangian points (L, L, L) lie along the line connecting the two large bodies, while t... |
how can i drink from bottles faster if i "shotgun" them with a straw? | When using a straw, you allow air to take the place of the liquid you are removing, without interrupting your drinking. | [
"To shotgun a beverage, a small hole is punched in the side of the can, close to the bottom. In order to prevent the liquid from spilling out while the cut is made, the can is held horizontally and the hole is made in the resulting air pocket. The hole can be made with any sharp object—typically a key, bottle opene... |
how much radiation does a microwave emit? what about cellphones too? is it enough to be significant or harmful? | No, both are non-ionising radiation and can't harm you in the way that X-rays can, if that's what you mean. That means they do not carry enough energy to strip electrons from atoms as ionising radiation does, which can cause genetic damage, radiation sickness and cancer if you're exposed to enough of it.
Microwaves ca... | [
"Microwave ovens, although shielded for safety purposes, still emit low levels of microwave radiation. This is not harmful to humans, but can sometimes cause interference to Wi-Fi and Bluetooth and other devices that communicate on the 2.45 GHz wavebands; particularly at close range.\n",
"The effect of mobile pho... |
why are some programs compatible with windows xp/vista, but not windows 7? | Because the programmer didn't update it. Most programs will either be updated, or run so they can run on either XP/Vista, 7, and even 8. It's just some expect Windows to be laid out a certain way and 7 is not laid out that way, so they can't work on 7. It's the developers of the programs fault, not Windows. | [
"Migrating from Windows 9x to XP can be an issue for users dependent upon MS-DOS. Although XP comes with the ability to run DOS programs in a virtual DOS machine, it still has trouble running many old DOS programs. This is largely because it is a Windows NT system and does not use DOS as a base OS, and because the ... |
Does matter contain information? | I'll try my best to interpret your question. (Apologies if I get it wrong.)
On a large scale, we can assign momentum to particles, and their past trajectories and interactions will describe their future positions quite accurately. This is [**classical mechanics**](_URL_3_), and it is a [*deterministic*](_URL_5_) theor... | [
"So matter is whatever physics studies and the object of study of physics is matter: there is no independent general definition of matter, apart from its fitting into the methodology of measurement and controlled experimentation. In sum, the boundaries between what constitutes matter and everything else remains as ... |
how does global population work? | > Does the global population steadily increase every day?
Yes that is generally how that works.
> If so, are there ever natural disasters/manmade disasters that have ever affected this?
The World Wars did a pretty big number, and it's possible that a significant event could impact the number slightly. But remem... | [
"The United Nations and other organizations routinely project the population of individual countries and regions of the world decades into the future. These demographic models are used by other organizations for projecting demand for services in all sectors of each economy.\n",
"Population change is analyzed by m... |
Is there no satellite image time series of the North Pole? | Here's a movie of the Arctic ice cap every September from 1979-2009. _URL_1_
And here's a link with other more recent historical ice data: _URL_0_ | [
"Until a 2013 review of satellite cartography, the northern pole of inaccessibility was thought to lie at , which was away from Ellesmere, Franz-Josef Land, and the New Siberian Islands, north of Utqiagvik, Alaska, and away from the actual northern pole of inaccessibility.\n",
"In the \"Sources\" section of his n... |
why does israel spy on the us? | Everyone spies on everyone as much as they are able if they are smart.
Making decisions requires information. If you don't have correct information then you are less capable of making the right decisions. Therefore if you value making the right decisions then you must also value pursuing accurate information, even if ... | [
"The United States and Israel have cooperated on intelligence matters since the 1950s. Throughout the Cold War, Israel provided the US with information on Soviet-built weapons systems captured from the Arabs. Israel also provides the US with much of its Middle Eastern human intelligence. The CIA became more reliant... |
Do elementary particles have an event horizon? | > Do elementary particles have an event horizon?
No. While the particles do not have a size their wave function does, and it is much larger than the size a black hole with the same mass would have. This is true for all particles with a mass below the Planck mass. It is unclear if elementary particles with a larger m... | [
"The concept of a particle horizon can be used to illustrate the famous horizon problem, which is an unresolved issue associated with the Big Bang model. Extrapolating back to the time of recombination when the cosmic microwave background (CMB) was emitted, we obtain a particle horizon of about\n",
"The particle ... |
does milk bond to chocolate? why doesn't the chocolate settle to the bottom of pre-made chocolate milk at the grocery store? | It depending on what type of bonding you mean.
What is occurring that the many different compounds are in a type of "suspension" within the liquid. These molecules fall between a gradient of [*homogenous* (same-type, same phase, distributed evenly), and *heterogenous* (different type, same phase, distrubited unevenly... | [
"Chocolate milk is sweetened chocolate-flavored milk. It can be made by mixing chocolate syrup (or chocolate powder) with milk (from cows, goats, soy, rice, etc.). It can be purchased pre-mixed with milk or made at home by blending milk with cocoa powder and a sweetener (such as sugar or a sugar substitute), melted... |
Are there equations that describe the effects that a magnetic field has on a plasma? | A plasma is effectively a collection of pseudo-free electric charges. A magnetic field **B** exerts a force **F** on an electric charge *q* traveling at velocity **v** according to:
**F** = *q* **v** x **B**
If you analyze this equation, you find that free electric charges with an initial velocity tend to spiral arou... | [
"These plasma formations also have the effect through \"magnetic, electric or electromagnetic (or even unknown field), appears to emanate from some of the buoyant charged masses. Local fields of this type have been medically proven to cause responses in the temporal lobes of the human brain. These result in the obs... |
how do scientists usually estimate very, *very* large numbers (e.g. number of stars or grains of sand on earth)? | It isn't difficult to estimate the number of grains of sand on the earth. We know roughly where sand is and how many grains there are in specific volumes like a teaspoon. We know how many teaspoons there are in a cubic meter. Sand can't hide. We can see how deep it is on the ocean floor with sonar. If its buried for a ... | [
"Using the stellar spectrum, astronomers can also determine the surface temperature, surface gravity, metallicity and rotational velocity of a star. If the distance of the star is found, such as by measuring the parallax, then the luminosity of the star can be derived. The mass, radius, surface gravity, and rotatio... |
why is so hard to breathe with just your head out of the water ? | The water pressure on your chest makes it harder for your lungs to expand to let in more air. This is more apparent when you try to breath from a pool noodle from farther below the water. | [
"When not breathing for long and dangerous periods of time in cold water, a person's body undergoes great temporary changes to try to prevent death. It achieves this through the activation of the mammalian diving reflex, which has 3 main properties. Other than Bradycardia and Peripheral vasoconstriction, there is a... |
How was the first parachute tested? | It was tested when there was no such thing as workplace safety regulations.
The first parachute jump of note is made by André-Jacques Garnerin from a hydrogen balloon 3,200 feet above Paris.
Leonardo da Vinci conceived the idea of the parachute in his writings, and the Frenchman Louis-Sebastien Lenormand fashioned a ... | [
"Project Excelsior was a series of parachute jumps made by Joseph Kittinger of the United States Air Force in 1959 and 1960 from helium balloons in the stratosphere. The purpose was to test the Beaupre multi-stage parachute system intended to be used by pilots ejecting from high altitude. In one of these jumps Kitt... |
what are the pros and cons of the uk leaving the european union? | Pros of leaving: They will better be able to control their borders. They will no longer be paying dues to the EU. They will be able to set more tariffs on imported goods.
Cons of leaving: Their citizenry will no longer be able to freely travel around Europe and so would need to get tourist visas. Their citizenry woul... | [
"As of January 2018, the European Commission had announced that three European agencies would be leaving the UK as a consequence of its withdrawal from the EU: the European Medicines Agency, European Banking Authority and the Galileo Satellite Monitoring Agency.\n",
"A recent, and perhaps the most widely known, p... |
Are there any animals who see heat radiation? | > (infra-red) it's surprising humans cannot see them.
Problem is almost everything emits infra-red at room temperature, so everything around you would look rather bright all the time. Some animals can see a bit into the IR, which makes small, hot prey more visible during a cool, dark night. | [
"The impact of radiation on individual animals has not been studied, but cameras in the area have captured evidence of a resurgence of the mammalian population – including rare animals such as the lynx and the endangered European bison.\n",
"The ability to sense infrared thermal radiation evolved independently in... |
Is there a literature/reading list about the Belgian colonization and rule of Belgian Congo? | A good place for you to start here would be [this AMA](_URL_0_) with Matthew G. Stanard, author of Selling the Congo: A History of European Pro-Empire Propaganda and the Making of Belgian Imperialism. | [
"Belgium had a colonial empire in Central Africa from 1908 to 1962, comprising the colony of the Belgian Congo (1908–60) and the international mandate of Ruanda-Urundi (1918–62). The territories were the responsibility of a Belgian parliamentarian who received the title Minister of the Colonies (, ) for most of the... |
According to Relativity, how fast would I need to travel before my mass was sufficient to collapse into a black hole? | This is one of the reasons people don't use this outdated increasing mass idea anymore. Your mass is your mass; it doesn't change or increase as you get to higher speeds. And good thing, too, because one of the fundamental tenets of relativity is that as long as you're moving at a constant speed, you might as well be a... | [
"As more mass is accumulated, equilibrium against gravitational collapse reaches its breaking point. The star's pressure is insufficient to counterbalance gravity and a catastrophic gravitational collapse occurs in milliseconds. The escape velocity at the surface, already at least 1/3 light speed, quickly reaches t... |
How do magnets get their magnetic fields? How do electrons get their electric fields? How do these even get their force fields in the first place? | Electrons have a fundamental property called the quantum mechanical spin. This spin can be understood and described as an intrinsic angular momentum.
The spin creates a magnetic dipole moment with a certain magnitude. In non-interacting electrons, these dipole moments are randomly oriented such that in average all mag... | [
"Magnetic fields are produced by moving electric charges and the intrinsic magnetic moments of elementary particles associated with a fundamental quantum property, their spin. Magnetic fields and electric fields are interrelated, and are both components of the electromagnetic force, one of the four fundamental forc... |
Are all spiderwebs chemically identical? | No, not all chemically identical. Yes spiders create different chemical structures for their silk depending on what it is used for. I worked in a laboratory where we studied spider silk. Basically in order to understand the differences in the different types of silk, and between species. We would feed the spiders food ... | [
"There is no consistent relationship between the classification of spiders and the types of web they build: species in the same genus may build very similar or significantly different webs. Nor is there much correspondence between spiders' classification and the chemical composition of their silks. Convergent evolu... |
how does copper in gloves, socks, or compression sleeves relieve pain? | It doesn’t do anything.
As for why it’s bogus; that would be because it doesn’t do anything.
Fools are easily parted from their money and there’s always someone willing to sell them some bullshit. | [
"Another common symptom of copper deficiency is peripheral neuropathy, which is numbness or tingling that can start in the extremities and can sometimes progress radially inward towards the torso. In an Advances in Clinical Neuroscience & Rehabilitation (ACNR) published case report, a 69-year-old patient had progre... |
We are taught that royalty historically married strategically for land, power, diplomatic alliances, etc. Are there well known instances of royalty marrying for love? | Personally I think the marriage of Lady Zhen to Cao Pi qualifies. In 204 the teenage Cao Pi was accompanying his father Cao Cao (yes, *that* Cao Cao) in his expedition to mop up the remains of Yuan Shao's faction, his greatest rival. Yuan Xi, a son of Yuan Shao, beat a hasty retreat to the lands of an allied warlord, l... | [
"Traditionally, many factors were important in arranging royal marriages. One such factor was the amount of territory that the other royal family governed or controlled. Another, related factor was the stability of the control exerted over that territory: when there was territorial instability in a royal family, ot... |
What are the statistical trends for the composition of planets in the universe? | Interestingly, the element abundances observed in the Sun are fairly typical for all stars in our stellar neighborhood... as [this site](_URL_0_) says:
> Solar System abundances are quite similar to those found in most stars and interstellar material in our neighbourhood and in corresponding parts of other galaxies w... | [
"A major problem in any theory is that the amplitudes of the perturbations are a function of the masses of the planets (and other factors, but the masses are the bottlenecks). These masses can be determined by observing the periods of the moons of each planet or by observing the gravitational deflection of spacecra... |
white male privilege | When controlling for other factors such as age and education, asian americans earnings are far below whites. Asian American immigrants tend to be highly educated compared to the average white American and thus get high paying jobs. ([here](_URL_0_) is a paper loaded with relevant data). The issue on that slide isn't (o... | [
"BULLET::::- White privilege refers to the myriad social advantages, benefits, and courtesies that come with being a member of the dominant race, such as a clerk not following you around in a store or not having people cross the street at night to avoid you.\n",
"In her 1988 essay, \"White Privilege and Male Priv... |
Was Stalin anti-Semitic? |
While we are waiting for answers to arrive, I believe that your questions were tangentially touched upon in these answers,
> Was Stalin anti-Semitic?
[Was Josef Stalin personally a racist?](_URL_2_) by [u/rusoved
](_URL_5_)
> Treatment of Jews in USSR
[Why did the USSR apparently become more anti-Semitic acros... | [
"Stalin publicly condemned anti-Semitism, although was repeatedly accused of it. People who knew him, such as Khrushchev, suggested he long harbored negative sentiments toward Jews, and anti-Semitic trends in his policies were further fueled by Stalin's struggle against Trotsky. After Stalin's death, Khrushchev cla... |
How was prohibition of alcohol passed seemingly very easily in the US? And why was it seemingly easily repealed only several years later? | u/LukeInTheSkyWith had a good detailed answer [here](_URL_0_).
| [
"In 1919, Prohibitionists succeeded in amending the Constitution to prohibit the sale of alcohol. Although the Prohibition period did result in lowering alcohol consumption overall, banning alcohol outright proved to be unworkable, as the previously legitimate distillery industry was replaced by criminal gangs whic... |
How did the M48 Patton and the T-55, the two main tanks of the Cold War during 1950s, compare with each other in terms of armor, firepower, mobility, and usability? | The M48 is notable for the odd shape of its lower and frontal hull, it being curved and boat-like. The use of steel armor on U.S. tanks reached its apex in the 1950s and 1960s; the last U.S. tank to use sheer thickness of steel plate as its primary means of protection was the M60. Similar to other U.S. tanks of the tim... | [
"The M46 Patton was an American medium tank designed to replace the M26 Pershing and M4 Sherman. It was one of the U.S Army's principal medium tanks of the early Cold War, with models in service from 1949 until the mid-1950s. It was not widely used by U.S. Cold War allies, being exported only to Belgium, and only i... |
Is there an inherent physical reason why Earth's seasons occur over the same period of time as its year? | The axis of rotation of the earth is tilted approximately 23 degrees from perpendicular to the ecliptic (the plane through which the earth's orbit occurs).
The tilt leads to the seasons. When the axis of rotation's north is away from the sun, the northern hemisphere is in winter. | [
"This suggestion is surprising because the seasons have been thought to be governed by the tilt of the Earth's axis (see Effect of sun angle on climate). The two types of years differ by a mere 4 days over 300 years, so Thompson's result may not be significant. However, the result is not unreasonable. The seasons c... |
how do most radio stations get music artists to say what station they are being played on? | Artists record those promos for the station. Usually they do a whole bunch at once and just send out the tapes. It helps both artists and stations promote themselves, so it's a win-win. | [
"Radio announcers are often known as disc jockeys (DJs). While some read from scripts, others completely ad-lib. These DJs’ tasks consist of on-air interviewing, taking/responding to listener requests, running contests, and making remarks about various subjects like the weather, traffic, sports, and other news. Mos... |
what is the mathematical constant, "i?" and, what is the importance of it? | Complex numbers can be written using two notations. Polar which is a magnitude and an angle, and rectangular. Rectangular gives the magnitude along the real axis and separately the magnitude along the imaginary (i) axis.
If you took both notations together, you'd see that the magnitude and angle in polar form exactly... | [
"A mathematical constant is a number whose value is fixed by an unambiguous definition, often referred to by a symbol or by mathematicians' names to facilitate using it across multiple mathematical problems. For example, the constant π may be defined as the ratio of the length of a circle's circumference to its dia... |
How Does the Center of Mass of a Dropped Slinky Move? | Yes. The [explanation is available on the channel](_URL_0_). | [
"A suspended Slinky's center of mass is accelerating downward at 16 feet per second per second (i.e., g); when released - the lower portion moves up toward the top portion with an equivalent, constant upward acceleration as the tension is relieved. As the spring contracts, every point along its length will accelera... |
Why didn't the Germans realise and/or fix the flaw in the Enigma Machine? | After the war, german cryptographers were asked that very question. The answer they gave was (simplyfied) "we knew of these weaknesses all along but we never thought someone would go to those lengths to break it." The brits didn't just build one "bomb", they build warehouses full of them! It was a huge operation that c... | [
"In December 1938 the Germans added additional rotors (up to six) and the number of combinations increased dramatically. The Germans believed that messages sent on their most sophisticated Enigma machines were so well coded that they could not be decoded. But Twinn and his colleagues proved them wrong.\n",
"Howev... |
how would einstein "work" on his ideas? how did he go from an idea to an equation? | A common way to work on an idea that's all math is to just mess about with established equations and/or axioms and see if you can't get it where you want it.
IIRC there was an instance - although this one was serendipity - where Einstein made an equation in which one component was an energy value, but he noticed this... | [
"Albert Einstein used Maxwell's equations as the starting point for his Special Theory of Relativity, presented in \"The Electrodynamics of Moving Bodies\", a paper produced during his 1905 Annus Mirabilis. In it is stated:\n",
"Einstein performed his analysis in terms of kinematics (the study of moving bodies wi... |
why was it so groundbreaking that ancient civilizations discovered/utilized the number 0? | To go a bit against the others here:
The fact that people discovered, that "nothing" can be expressed as a number - that you can also calculate with - is not obvious and very revolutionary.
It shows a new level of abstract thinking that actually leads to mathematics as something different than just "counting things".... | [
"A much later advance was the development of the idea that can be considered as a number, with its own numeral. The use of a 0 digit in place-value notation (within other numbers) dates back as early as 700 BC by the Babylonians, but they omitted such a digit when it would have been the last symbol in the number. ... |
how do electrons in an electrical current actually travel? do they jump from atom to atom? | No. One of the special features of conducting metals is that their outermost electrons are basically shared between all of the atoms. So they act as if they were free electrons bouncing around all over the place. When there is a current they bounce more in one direction than they do in the others, and so there is a net... | [
"Therefore, in this wire the electrons are flowing at the rate of . At 60 Hz alternating current, this means that within half a cycle the electrons drift less than 0.2 μm. In other words, electrons flowing across the contact point in a switch will never actually leave the switch.\n",
"Electrons can move (slowly) ... |
How do we know what an animal’s field of vision looks like? I.e. how can we tell that rodents see in yellow hues and that certain insects can see UV light? | Because we can stick electric probes into their eyes and brains and see what happens when we shine different types of light at them. Not even joking. In the olden days we would chop out bits of retina to get the photoreceptors and then measure which wavelengths of light they absorbed or otherwise reacted to. Also not e... | [
"Eyes in various animals show adaptation to their requirements. For example, the eye of a bird of prey has much greater visual acuity than a human eye, and in some cases can detect ultraviolet radiation. The different forms of eye in, for example, vertebrates and molluscs are examples of parallel evolution, despite... |
Why were some German companies closely tied to the Nazis (Daimler-Benz, for example) allowed to continue after the war, instead of being broken up like IG Farben? | Followup question: Why was Mitsbubishi allowed to continue operations? Did other Japanese manufacturers have the same fate as IG Farben? My instincts tell me that we didn't want to cripple their industry but I don't see why there wasnt at least a little "rebranding".
Did it have to do with whether or not they were a... | [
"When Adolf Hitler came to power in 1933, the Third Reich initiated \"Arisierung\", a policy of Aryanization of German businesses. As a consequence of this, Koppel was forced to divest himself of \"Auergesellschaft\" and his banking house. The German corporation \"Degussa\" took control of \"Auergesellschaft\" in 1... |
How are scientists using the transit method to find exoplanets so certain that it is a planet that's responsible for the change in brightness of the star? | Because they watch to see the dimming happen three times, so it can't be just some dust cloud, and because an asteroid doesn't cause a big enough drop in brightness for us to be able to detect it. Also, a dust cloud would cause not just dimming but a lot of reddening, and the shape of the light curve would be very diff... | [
"The transit method of discovering exoplanets relies upon carefully monitoring the brightness of a star. If a planet is present and crosses the line of sight between Earth and the star, the star will dim at a regular interval by an amount that depends upon the radius of the transiting planet. In order to measure th... |
do publicly traded companies place greater focus on short-term results than long-term? | Someone else will likely have a more thorough explanation but it all comes down to shareholder pressure. A better run company will not sacrifice future profit for a quick short term gain but under shareholder pressure they may have to make those decisions.
Larger companies under more public (press) scrutiny will li... | [
"Also there is the tradeoff of short term gains at the expense of long term gains or even long term company survival. It is easy to plunder the assets of a previously successful company and show spectacular short term gains only to have the enterprise collapse after those responsible have gotten their incentives an... |
how can a coax cable carry a hd signal from the wall to my cable box, but i need hdmi or component to get the hd signal from the box to my tv? | Cable uses compression, and so far there is no standard for compression between the box and display, at least the content owners will allow, for fear of content piracy.
Consoles and such do not have hardware to compress video, so need a direct connection. | [
"Typically, a cable converter box has two coaxial F-type female connectors; one \"Cable In\" for a coaxial cable from the wall jack (containing the CATV signal), one \"TV Out\" connected to the television where an antenna or other RF device (such as a VCR) would be connected. Newer cable boxes also tend to come sta... |
how does red shift show that the big bang theory could be a possible theory, for the formation of the universe? | Red shift is the evidence of what happened. After the invention of the telescope, people found out that there were many more stars than we thought previously, because we couldn't see them before. We found more and more and more of them and catalogued them over a couple hundred years.
Then we discovered that many of t... | [
"The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution. Despite its success in explaining many observed features of the universe including galactic redshifts, the relative abundance of light elements such as hydrogen an... |
Does the expansion of the universe produce work? | Energy is not a globally conserved quantity in General Relativity, which means that energy doesn't necessarily have to come from anywhere!
Energy is still conserved locally, which basically means that is is conserved as long as you restrict your observations to a small enough region of space-time. However, there is no... | [
"The expansion of the universe reaches an infinite degree in finite time, causing expansion to accelerate without bounds. This acceleration necessarily passes the speed of light (since it involves expansion of the universe itself, not particles moving within it), causing more and more objects to leave our observabl... |
why is my sight full of extremely small and multi-colored dots? | [Visual Snow](_URL_0_) or Mardi Gras. | [
"The numerous eyes are very small and hardly visible to the naked eye. They are distributed marginally on the first millimeters of the body and posteriorly become dorsal, covering the two most external stripes on each side. The eyes that cover the stripes are surrounded by halos, zones without pigmentation, which m... |
Before the B-52's flew over Hiroshima the Japanese secret agents had intel that they would be dropping a dangerous bomb. Why was no alarm raised? | I've seen no credible source that suggests the Japanese had any kind of intelligence of this sort. Japanese intelligence was not especially accomplished when it came to the United States. Neither the Germans, nor the Japanese, had any good evidence of the US atomic bomb project, though the Germans did [occasionally get... | [
"On 6 August 1945, the B-29 bomber Enola Gay flew over the Japanese city of Hiroshima in southwest Honshū and dropped a gun-type uranium-235 atomic bomb (code-named Little Boy by the U.S.) on it. Two other B-29 aircraft were airborne nearby for the purposes of instrumentation and photography. When the planes first ... |
how do games like overwatch and battlefield 1 (and others) allow you to play the games while still downloading? | You decide to order a boardgame online.
You get your friends together every week to play.
The package arrives, you find out that the the fancy game pieces are being shipped separately because they were heavy.
However your friends are still there, you find that the box you just received contains the game rules, th... | [
"Along with the games, customers are also able to download numerous extra materials relating to the game they purchased. Often these extras include the game's soundtrack (partly as FLAC), wallpapers, avatars, and manuals. GOG.com also offers full customer support for all purchases and a money-back guarantee for the... |
On animals with color patterned fur, what is happening in the hair follicle to create a single strand of hair with multiple colors? | Alan Turing, of WWII cryptography fame and of computer science fame, wrote an article on [morphogenesis](_URL_0_), describing a physical and chemical basis by which patterns in/on fur/hair and skin arise. The wiki article links to a pdf of Turing's paper.
From the wiki article, "The theory (which can be called a react... | [
"The mammalian proteins Agouti signalling peptide and Agouti related peptide are the only known mammalian examples of this motif. Both are neuropeptides involved in cell signalling. The former is responsible for hair (fur) colouration.\n",
"Characteristic hair help to distinguish \"C. subspirale\". The lateral ha... |
If the universe was formed in a single event, why isn't it homogeneous? As in, why do stars and planets have vastly different compositions if they originated from the same point? | The leading theory is that during the period of cosmic inflation, in which the universe expanded much faster than the speed of light, quantum mechanical fluctuations were collapsed and then magnified as they expanded, which lead to the fluctuations that caused galaxies and the like.
Planets and stars have different co... | [
"Isotopic “anomalies” in meteorites indicate that the solar system was not homogeneous when formed. Similarly, the Galaxy is neither uniform in space nor constant in time due to continuous stellar nucleosynthesis. \n",
"The huge variety of the shapes is partially the projection effect—the same nebula when viewed ... |
How likely was a Catholic crusade against Henry VIII after the break with Rome? | Part of the issue with a crusade in the 16th century is that Crusades require a submission of the will of the nation to the will of the Pope. But not only was nationalism rising (huge topic, not going into it here), but there was a great turning away from Rome as the source of Christianity.
Regardless of the religious... | [
"Pope Innocent declared Raymond anathematized and released all of his subjects from their oaths of obedience to him. However, Raymond soon attempted to reconcile with the Church by sending legates to Rome. They exchanged gifts, reconciled, and the excommunication was lifted. At the Council of Avignon (1209) Raymond... |
if blood flow helps heal wounds, why is it recommended to elevate the limb where the injury occurred? | For cuts, if the blood is flowing too fast, it won't clot as easily. Pooling blood clots better, so you raise the limb to slow the flow of blood to the injury. This allows the blood that's already there to clot more easily and stop the bleeding.
For other injuries, elevating the injury can help limit pain, swelling, a... | [
"Improvised tourniquets, in addition to creating potential problems for the ongoing medical management of the patient, usually fail to achieve force enough to adequately compress the arteries of the limb. As a result, they not only fail to stop arterial bleeding, but may actually increase bleeding by impairing veno... |
Egyptologists - How was the age of the Great Sphinx of Giza determined? And is it at all possible that it can be (far) older? | The Sphinx Temple was built with stones cut out from the Sphinx colosseum, so they are the same age.
The Sphinx Temple was built after the Khafre Valley Temple because it was built upon the foundation of the north enclosure wall of the Khafre Temple and even incorporates one of its stones.
Also, the Sphinx enclosure... | [
"Some early Egyptologists and excavators of the Giza pyramid complex believed the Great Sphinx and associated temples to predate the Fourth Dynasty rule of Khufu, Khafre, and Menkaure. Flinders Petrie wrote in 1883 regarding the state of opinion regarding the age of the nearby temples, and by extension the Sphinx: ... |
I watched "How Beer Saved The World" and most of it seems to be exaggerated, but how much is true? | I also watched "How Beer Saved the World" and came to Ask Historians with questions.
The part about Sumerians drinking beer pretty much all day long was supported by several redditors here. It seems it wasn't nearly as alcoholic as the beer we know and love; and was a very nutritionally valuable grain-product, even m... | [
"How Beer Saved the World is an hour-long documentary that was broadcast on the Discovery Channel on January 30, 2011. Produced by Australian production company Beyond Productions, the documentary takes a look at the origins of beer and how it has had an influence on major events in human history such as the buildi... |
How does DNA decide where a protein is used? | Tissue-specific proteins are expressed only in the tissues with the proper [transcription factors](_URL_1_) or [chromatic structure](_URL_2_). For the protein to go to the right place within the cell, the proteins are sorted by a short code called a [target peptide](_URL_3_) at the N-most end of the protein.
If protei... | [
"DNA stores the information required to assemble, maintain and reproduce every living organism. A protein is a large molecule (\"macromolecule\") made up of smaller subunits, amino acids. DNA sequences are made up of codons, three-long nucleotide stretches, that correspond to specific amino acids. DNA creates RNA w... |
Does the ISS / Astronauts on it ever get a magnificent view of the unobstructed stars? | The cupola is always pointed at Earth, but you can see the sky to the sides.
> Is there a way to calculate how often an ISS-eclipse happens? I don't think that's the right word, it's like watching Earth transit in front of the sun from the perspective of ISS, is that an Earth transit or an ISS-eclipse?
Normally onc... | [
"4. There are no stars in any of the photos; the Apollo 11 astronauts also stated in post-mission press conferences that they did not remember seeing any stars during EVA. Conspiracists contend that NASA chose not to put the stars into the photos because astronomers would have been able to use them to determine whe... |
If gravity acts via gravitational waves, is it possible to create an anti-gravitational to cancel out gravity? Sort of like noise-cancelling headphones? | Gravity does not act via gravitational waves. One theory to explain how gravity could work suggests that there should be waves (as a biproduct). Scientists believe they may have detected these waves, which in turn adds weight to the validity of the theory. | [
"Although the strongest gravitational wave from EMRIs may easily be distinguished from the instrumental noise of the gravitational wave detector, most signals will be deeply buried in the instrumental noise. However, since an EMRI will go through many cycles of gravitational waves (~10) before making the plunge int... |
why does faxing from a smartphone seem to require a third party to do the conversion and transmission? you're using a phone; why can't the conversion be done on your device and the audio fax signals be sent directly to another fax machine. | It's mainly because the mobile voice protocols send your speech data in little packets, and allow for some of these packets to be lost, because having tiny gaps in the sound is more acceptable than a long delay (which you'd get if you insisted on resending lost packets).
The Fax protocol, on the other hand, is designe... | [
"In this method, smartphones are used to send and receive fax without the need to have any landline phone or any extra hardware. There are several fax applications (for both Android and iOS) that handle the mobile-based faxing. \n",
"Making phone calls over the Internet (Voice over Internet Protocol, or VoIP) has... |
What makes low mass brown dwarfs different from gas giants? | [Wikipedia has a section on it.](_URL_0_) There's no strict dividing line. Brown dwarves have been defined as having at least 13 jupiter masses, but it's more of a rule of thumb. They're about just large enough to fuse deuterium, but it's not a strict cutoff. | [
"Brown dwarfs form like stars from the direct gravitational collapse of clouds of gas and this formation mechanism also produces objects that are below the limit and can be as low as . Objects in this mass range that orbit their stars with wide separations of hundreds or thousands of AU and have large star/object m... |
what is the evolutionary benefit of certain plants such as tobacco or marijuana containing chemicals that can affect the animal mind? | Nicotine at least is a fairly potent insecticide. The fact that it also gives people a bit of a buzz is just a happy accident. | [
"Herbivores have created selective pressure for plants to possess specific molecules that deter plant consumption, such as nicotine, morphine, and cocaine. Plant-based drugs, however, have reinforcing and rewarding effects on the human neurological system, suggesting a \"paradox of drug reward\" in humans. Human be... |
how do vines support themselves when they are not "wrapped" around a rigid structure? | Those little squiggly things with round things at the ends are like suction cups. They grab onto the surface and infiltrate into microscopic grooves and cracks and that's how they adhere. | [
"The vines are selected by a village elder and matched with each jumper's weight without any mechanical calculations. The vines need to be supple, elastic, and full of sap in order to be safe. The ends of the vines are shredded to allow the fibres to be looped around the ankles of the jumpers. If the vine is too lo... |
How does the solar cycle reset? | It's a fairly complicated process but the diagram is not the full cycle. Once you go past the last picture, the tightly wound up magnetic field lines get lifted up through to magnetic lift with the Coriolis force twisting the lines into loops. At some point these loops will break the field line and reconnect forming a ... | [
"The \"solar corrections\" approximately undo the effect of the Gregorian modifications to the leap days of the solar calendar on the lunar calendar: they (partially) bring the epact cycle back to the original Metonic relation between the Julian year and lunar month. The inherent mismatch between sun and moon in th... |
Why does eye colour change (or appear to) in natural/false light? | The color of your eyes is dependent upon the light being reflected by them. Sunlight and artificial light are composed of different mixtures of photons at varying energies, and the color of your eyes will appear to change as the light reflecting off of them change.
That being said, I recall reading somewhere once tha... | [
"Perceptual constancies are sources of illusions. Color constancy and brightness constancy are responsible for the fact that a familiar object will appear the same color regardless of the amount of light or color of light reflecting from it. An illusion of color difference or luminosity difference can be created wh... |
how a spray bottle works. | As the trigger is pulled, air is pumped into the chamber with the liquid. Once the pressure is increased, the liquid is displaced by the gas (air) and spurts out of the nozzle of the sprayer. | [
"A spray bottle is a bottle that can squirt, spray or mist fluids. A common use for spray bottles is dispensing cool cleaners, cosmetics, and chemical specialties. Another wide use of spray bottles is mixing down concentrates such as pine oil with water.\n",
"Unlike the rubber bulb dispenser which primarily moved... |
what would happen if global warming was reversed, and the earth was dropping in temperature? | Uh, what is the opposite of hot?
Go watch the kids movie Ice Age... There's your ELI5 | [
"The World Bank and the International Energy Agency warned that the world is heading for unprecedented warming – of between 4 °C and 6 °C – if trends are not reversed. That scale would result in droughts, floods, heatwaves and fiercer storms, decline agricultural productivity, bring plant and animal extinctions, an... |
are all the stars we see in our night sky part of milky way, or some belong to other galaxies too? also, how do we know if a star is from other galaxy? | All the stars you see at night are part of the Milky Way. Most are "close" as far as stars go.
The nearest major galaxy is 2,500,000 light years away, you'd never see an individual star at that distance without an incredibly powerful telescope.
It's possible for a star to originate in one galaxy and get ejected in t... | [
"With the exception of supernovae, individual stars have primarily been observed in the Local Group, and especially in the visible part of the Milky Way (as demonstrated by the detailed star catalogues available for our\n",
"The Milky Way is visible from Earth as a hazy band of white light, some 30° wide, arching... |
how is amazon able to fulfill such a wide variety of different types of product orders in such a short time (same day, next day, etc.)? | Amazon maintains large facilities all over the world stocked with common items.
This allows you to ship as short a distance as possible and consequently get same day or next day delivery.
If you look for something esoteric and strange you'll see that two day is about as fast as they can get to you. | [
"Amazon Supply, launched in 2012, offers industrial and scientific components and maintenance, repair and operations (MRO) supplies. Amazon Supply was developed based on experience operating Smallparts.com, acquired in 2005. (The Smallparts.com brand was discontinued with the launch of Amazon Supply.) While Amazon ... |
Can a brittle solid, like glass, be warped permanently without breaking it by keeping it under a constant, but low, pressure? | *All* materials can be permanently deformed over time by applying stress. Even brittle solids, even at temperatures less than the melting temperature (or, for that matter, the glass transition temperature). The phenomenon is called [creep](_URL_1_), and it occurs because there's a nonzero chance of atomic bonds breakin... | [
"It is this compressive stress that gives the tempered glass increased strength. This is because annealed glass, which has almost no internal stress, usually forms microscopic surface cracks, and in the absence of surface compression, any applied tension to the glass causes tension at the surface, which can drive c... |
How accurate is the cliche of useless aristocrats making up the top ranks of western armies? | Okay, so to preface this, my expertise falls a little after the period you specified- However, I hope it answers at least some of your question.
In the British Army, at least, the aristocracy proper constituted only a small proportion of the officer class. Only 13% of the Army's colonels in 1854 came from aristocratic... | [
"He is considered one of the more famous generals in Chinese history, not only because of his military achievements, but also because he demonstrated perseverance and respect to his friends and subordinates. In addition to his military skills, his exhortations on personal discipline were also highly regarded. His d... |
how do crematoriums ensure only the one person's ashes are in the urn? | In 2002 in Georgia, a small family run crematorium was found to have distributed urns containing a mixture of burned wood chips and dirt, while at least 120 rotting corpses were found piled in sheds surrounding the property. Apparently their furnace had broken down, and the family couldn't afford to fix it. The state o... | [
"Besides the traditional funeral or cremation ashes urns, it may also be possible to keep a part of the ashes of the loved one or beloved pet in keepsake urns or ash jewellery, although this might be banned in some localities as the law of certain countries may prohibit keeping any human remains in a private reside... |
Is there any truth to chinas claim that they had settlements such as fishing villages in northern Australia | You are referring to the trade in trepang (sea cucumbers) conducted by Makassan fishermen along the coast of northern Australia, mostly between roughly 1740 and 1900. Trepang was a delicacy in fashion for Chinese cookery after 1600, so the ultimate destination of the catch was China. But there is little to no evidence ... | [
"Some historians have theorised that Northern Indigenous Australians may even have had dealings with Chinese traders or come across Chinese goods particularly through trepanging. Sir Joseph Banks was of the opinion that any British colony in Australia could be populated by 'useful inhabitants from China'. The first... |
If a child was raised with no human contact and without hearing speech once, what accent would they naturally employ? | One big misconception of accents is that they're somehow inborn, immutable characteristics. This simply isn't the case.
All an accent is is the way one pronounces their language. That's it. Some aspects can be affected by physical abnormalities, but for the most part it's all learned. If we were to teach language to s... | [
"The deaf children of hearing parents may not have significant exposure to any language in early childhood. Because of their sensory loss, these children perceive little of their parents' speech. Because in most cases the parents do not sign the children are also not exposed to a conventional sign language. (Meier)... |
why do people still worship god in the 21st century? | Higher meaning to life's existence. Spiritual experiences they've had. Faith is explicitly believing in something that you cannot see that is true. A sense of community and shared morals.
The list goes on. | [
"In modern society and sociology, some writers have commented on the ways that people no longer simply worship recognised deities, but also (or instead) worship consumer brands, sports teams, and other people (celebrities). Sociology therefore extends this argument to suggest that religion and worship is a process ... |
My friend told me he thinks microwaved water kills plants. I call on you all to help me convince him that microwaves are perfectly safe. | It's complete hogwash. Nothing happens when you microwave (pure) water other than it gets warmer. There's no way of telling, even in theory, whether or not some quantity of water has been microwaved in the past or not.
I'm afraid you won't find any articles in Scientific American, because they don't usually bother to... | [
"In a July 2012 post (which has since been removed), Hari quoted the ideas of Masaru Emoto that microwave ovens cause water molecules to form crystals that resemble crystals exposed to negative thoughts or beliefs, such as when the words \"Hitler\" and \"Satan\" were exposed to the water. Steven Novella calls Emoto... |
what the hell is "rent-to-own?" | Rent-to-own - You pay a fixed monthly for the use of an item for a specified period of time, before you own the item. Up until that time, the item doesn't belong to you. The **store owns** the item. The store may take that item away from you. Similarly, you might decide you do not like the item and therefore return it ... | [
"Rent-to-own, also known as rental-purchase, is a type of legally documented transaction under which tangible property, such as furniture, consumer electronics, motor vehicles, home appliances, real property, and engagement rings, is leased in exchange for a weekly or monthly payment, with the option to purchase at... |
if most of africa is so poor and wages are so low, why is everything made in asia and not africa? | wages being low is good for manufacturing, but having your factory under the control of various tribal warlords and having to bribe the various tribes constantly to avoid it being burnt down and all your employees killed is not good for manufacturing. | [
"Africa's economic malaise is self-perpetuating, as it engenders more of the disease, warfare, misgovernment, and corruption that created it in the first place. Other effects of poverty have similar consequences. The most direct consequence of low GDP is Africa's low standard of living and quality of life. Except f... |
What was life like in Mussolini's Italy? Just how "fascist" was it, compared to other dictatorships? Did this change over time, or stay the same? | Its hard to answer a question like "what was life like" because it differs for every individual. But generally speaking Italy remained poor compared to its Western European counterparts or its axis counterparts and Mussolini never really did much to actually help the situation. For example in 1938, Italy's GDP was 140.... | [
"With the concept of totalitarianism, Mussolini and the Fascist regime set an agenda of improving Italian culture and society based on ancient Rome, personal dictatorship and some futurist aspects of Italian intellectuals and artists. Under Fascism, the definition of the Italian nationality rested on a militarist f... |
[META] r/AskHistorians rules – now with extra awesome! | One question: it used to mention in the rules that a flaired user (such as myself) was not held to the standard of flaired users, just the normal top level comment standards (i.e. not required to be an expert, but still contributing something useful) when replying outside their field. Is that guideline still in place?... | [
"\"Up-Goer Five\" became the basis of \"Thing Explainer\". In an interview with \"The New York Times\", Munroe stated that \"the word limit is fun, because it forces you to think about it some more.\" Published by Houghton Mifflin Harcourt (HMH) on November 24, 2015, the book was initially sold for $25 USD. \"Wired... |
Are there any notable natural satellites around the Sun that orbit outside the similar plane of the planets? | Yes there are! While the planets are all fairly close to the plane of the ecliptic (Mercury is the farthest out of the ecliptic, orbiting in a plane tilted at about 7 degrees to our own), there are a lot of smaller objects that orbit significantly out of the plane. [Eris](_URL_0_), the most massive dwarf planet and 9th... | [
"Except for the largest, which are in hydrostatic equilibrium, natural satellites (moons) differ from small Solar System bodies not in size, but in their orbits. The orbits of natural satellites are not centered on the Sun, but around other Solar System objects such as planets, dwarf planets, and small Solar System... |
why do multi-packs on amazon often cost more than buying multiple of an individual product? | Could be an issue with the packaging. Depending on the weight of the goods they might have calculated their shipping cost on a bundle to be more since they might have to use a larger box or a different shipping service. | [
"Bundled pricing is the approach of selling products and their accessories or other options as one product for one price. Consumers will not need to purchase each item separately but one bundled item and priced as one product. This would also be appealing to customers as normally they would be on sale and have the ... |
Why wasn't there more contact between Polynesia and the Old World until the Age of Exploration? | I'm confused by this question. There are no [Polynesians](_URL_0_) in Indonesia. There is hardly a "continuous" archipelago all the way to Easter Island. What's more is that there are literally over 1000 languages spoken in Oceania so it's not particularly easy to make sustained contact with a large group of people. Di... | [
"Anthropologists continue to believe that Polynesia was settled from west to east, based on linguistic, physical, and genetic evidence, migration having begun from the Asian mainland. There are controversial indications, though, of some sort of South American/Polynesian contact, most notably in the fact that the So... |
does energy have a weight or mass? | Light (photons) doesn't have mass, but it has momentum.
Batteries rely on electrochemical reactions to provide electricity. (A chemical reaction that produce electrons). Electrons do have a mass (although tiny) so a battery theoretically weight a little more when charged.
[edit] for the reason cited below, not because ... | [
"Energy gives rise to weight when it is trapped in a system with zero momentum, where it can be weighed. It is also equivalent to mass, and this mass is always associated with it. Mass is also equivalent to a certain amount of energy, and likewise always appears associated with it, as described in mass-energy equiv... |
why do people use the term "son" in a generic sense to address a boy but not "daughter" to address a girl? | I'm not sure so don't take this as an answer, but maybe it's because daughter has two syllables as opposed to one. Daughter doesn't roll off the tounge as easily. I dunno though | [
"Naming a child after a relative, friend, or well-known person is a common practice in the English-speaking world. When a son is named for his father, it is customary (primarily in the United States) to add \"Jr.\"/\"II\", \"III'\", or another name suffix to the name of the son (and sometimes \"Sr.\" or a prior num... |
Are electrons and protons and other particles eternal? | This is one of the [unsolved problems of physics](_URL_0_); the short answer is that we do not know. A proton has never been observed to decay on its own, and neither has an electron. Electrons are (as far as we know) fundamental - that is, it is not made up of smaller pieces, meaning that there is nothing into which... | [
"Protons and neutrons are best known in their role as nucleons, i.e., as the components of atomic nuclei, but they also exist as free particles. Free neutrons are unstable, with a half-life of around 13 minutes, but they are common in nature and have important applications (see neutron radiation and neutron scatter... |
what is nitrous and how does it work? | Air has a nitrogen/oxygen ratio of about 4:1. Nitrous oxide has a nitrogen/oxygen ratio of 1:2. Combustion relies on oxygen, and so the density accelerates the reaction.
Cars using a nitrogen system will have tanks of NO2, and plumbing from the tank to a solenoid, which is just a valve that's actuated by a motor. The ... | [
"The name Nitro derives from nitrocellulose, the main ingredient in smokeless gunpowder. The Nitro area was to be the American ammunition production facility during World WarI. Daniel C. Jackling \"supervised the construction and operation\" of the plant, which by the time of the armistice \"was producing one hundr... |
Why did Rome only have proconsuls and propraetors? | Praetors and consuls maintained the necessary *imperium* to command armies. As such praetorian or consular *imperium* was necessary to command an army in the provinces, where administration necessarily in the Republic entailed military command (the *imperium maius* made this a more complicated question under the Princi... | [
"In the Roman Republic, a proconsul was typically a former consul and thus an experienced commander-in-chief. Having held the Republic's highest office, he was a statesman as well as an administrator. Rome's patrician class was prepared to exercise aristocratic leadership, both civil and military.\n",
"The \"prae... |
How Eurasia and Americas are connected for internet, telephone, etc.? | Yes, we have many cables lining the ocean floors. [Here is a map.](_URL_0_) | [
"Furthermore, international networks exist with institutions in the USA (e.g. Hoover, Harvard and the Zimmerli Art Museum, New Brunswick) and Western Europe (e.g. ETH Zürich, the University of Amsterdam and Cambridge University).\n",
"In November 1992 the first international communication connection was establish... |
if it's legal to jack up life-saving prescription prices, why is it illegal to sell my life-saving organs? | Its illegal to sell your organs because that very very quickly starts abusing poor people. Rich people who are sick could essentially just at will put pressure on poor people to replace organs of theirs. Do we really want to live in a society where we can essentially blackmail poor people to give up their organs?
Pric... | [
"Critics often argue that organ sales should remain prohibited because any market solution will take advantage of the poor. Specifically, they fear that a large financial incentive for donating organs will prove irresistible to individuals in extreme poverty: such individuals may feel like they have no choice but t... |
I'm fascinated by ancient and "lost" civilizations/cities. Can you tell me about some I haven't heard of? | I can give you a ton from the new world.
One of the best is the ancient city of [Teotihuacan](_URL_2_). It's contemporary with the later Roman Empire. At 100,000 people, it was the largest city in the Western Hemisphere and one of the top 10 largest cities in the world. It was a cosmopolitan city who's original ethnic... | [
"In the popular imagination lost cities are real, prosperous, well-populated areas of human habitation that have fallen into terminal decline and been lost to history. Most real lost cities are of ancient origins, and have been studied extensively by archaeologists. Abandoned urban sites of relatively recent origin... |
Why didn't the Luftwaffe destroy the Royal Navy to ensure Operation Sea-lion's success? | > but with Germany's ridiculously overpowering air presence
Well there is problem number 1! They didn't, at any point in Summer and Fall Germany enjoy even air superiority let alone air supremacy over England. Limited action time, and losses that were irreplaceable in the long run contributed to mean they were never... | [
"Anthony Cumming judged that the immense superiority of the Royal Navy in home waters together with the anti-maritime limitations of the Luftwaffe were the main reasons for effectively abandoning Operation Sea Lion in 1940. In 1958, Duncan Grinnell-Milne submitted his case on behalf of the Royal Navy and in 1960 wa... |
why is aspirin so much cheaper than other nsaids? | Aspirin has been produced synthetically for over 100 years, there are no patents on it, and any brand can use the name Aspirin legally. | [
"Aspirin use has been shown to increase the risk of gastrointestinal bleeding. Although some enteric-coated formulations of aspirin are advertised as being \"gentle to the stomach\", in one study, enteric coating did not seem to reduce this risk. Combining aspirin with other NSAIDs has also been shown to further in... |
How does the Feynman One-Electron universe postulate work? | In the quantum theory of electromagnetism, quantum electrodynamics, there is really only one sort of interaction which exists. You draw it on a Feyman diagram with three lines (two straight and one squiggly) meeting at a point. The two straight lines represent electrons (or positrons), and the squiggly line is a photon... | [
"The one-electron universe postulate, proposed by John Wheeler in a telephone call to Richard Feynman in the spring of 1940, is the hypothesis that all electrons and positrons are actually manifestations of a single entity moving backwards and forwards in time. According to Feynman:\n",
"Bohr developed the Bohr m... |
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