question stringlengths 3 301 | answer stringlengths 9 7.04k | context listlengths 7 7 |
|---|---|---|
If your body produces antibodies after defeating a pathogen indefinitely, when an individual gets exposed to many pathogens throughout their life, will they have a larger antibody density in their blood? Is there a limit to this? | Antibodies are made as you require them. They are made by lymphocytes, after an infection you havea low number lymphocytes called memory cells in your blood these can build the antibodies required if you are exposed to the pathogen again.
The original process of producing an antibody for an infection is a random proce... | [
"Even if the host does develop antibodies, protection might not be adequate; immunity might develop too slowly to be effective in time, the antibodies might not disable the pathogen completely, or there might be multiple strains of the pathogen, not all of which are equally susceptible to the immune reaction. Howev... |
why aren't there any laws limiting the use of plastic? | Because people want plastic things, a lot. The innovation of plastic products completely changed the world. People in general don't want to stop using plastic. | [
"Recycling, banning, and taxation fails to adequately reduce the pollution caused by plastic bags. An alternative to these policies would be to increase extended producer responsibility. In the US, under the Clinton presidency, the President's Council on Sustainable Development suggested EPR in order to target diff... |
In "The Dialectic of Sex," Shulamith Firestone claims that childhood was essentially an invention of the 15th century, and that before that point male children were treated as adults and functioned perfectly well in adult society. Is this true? | I'm not familiar with Firestone's book, but I've written a few times on childhood and adolescence in the premodern world here on AH.
* [Historiography of children and childhood](_URL_0_)
* [Is adolescence an invention of the 20th century?](_URL_1_) (This has more to do with teenage-hood as a distinct life stage)
Ment... | [
"Her book \"Meanings of Sex Difference in the Middle Age: Medicine, Science, and Culture\" (1993) was groundbreaking in its examination of sex and gender, and has deeply influenced subsequent scholarship. Cadden examines the discussions of sexual difference from Aristotle through the fourteenth century, revealing a... |
Is time dilation the same at every black-hole event horizon? | Might I be able to also ask a question regarding black holes, their shape etc.?
From what I understand, there's a region on the edge of the event horizon is a photon sphere where photons moving on a tangent to this will become trapped in orbit.
However when I've seen pictures regarding black holes - particularly sho... | [
"There are real phenomena that cause time dilation similar that of a stasis field. Extremely high velocities approaching light speed or immensely powerful gravitational fields such as those existing near the event horizons of black holes will cause time to progress more slowly. However, there is no known theoretica... |
why is it so difficult for the medical community to give a straight answer about how much a procedure/appointment/etc. will cost? | The doctors and nurses don't even *know* how much shit costs. They just say what work they've done & the billing department handles the prices.
Billing can't give you a straight answer because they have different rates for cash payments or insurance. Every insurance company negotiates a set of rates they'll pay fo... | [
"The American Medical Association showed that asking simple single item questions, such as \"How confident are you in filling out medical forms by yourself?\", is a very effective and direct way to understand from a patient's point of view how they feel about interacting with their healthcare provider and understan... |
do programs like lumosity have any measurable benefit to cognitive abilities? or is it all just hype? | Using Lumosity regularly makes you better at Lumosity. It might be of more benefit to your cognition than staring at a wall and picking your nose, but it's mostly hype and pseudoscience | [
"Kable researches cognitive neuroscience. His work has suggested that an individual's approach to risk in decision making is correlated with the anatomical structure of the brain. Another of Kable's projects concluded that \"Brain Training\" using Lumosity software “appears to have no benefits in healthy young adul... |
How was helium identified from the continuous spectrum of the sun? | The sun's photosphere is cooler than the regions below it, creating absorption lines. If you point a spectrometer at the sun you don't get a continuous spectrum, you get a continuous spectrum superimposed with black lines where the particular wavelength was absorbed by the cooler upper atmosphere. Those absorption line... | [
"The first evidence of helium was observed on August 18, 1868, as a bright yellow line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun. The line was detected by French astronomer Jules Janssen during a total solar eclipse in Guntur, India. This line was initially assumed to be ... |
What would the ramifications of a lack of causality be? | Unpredictability. The equations of motion lose existence and uniqueness. Given a certain initial condition at time t, there might not exist a solution to later time, or there might be infinite equally valid. Essentially the Universe doesn't know what to do with itself, and even if it does, there is no way of predicting... | [
"Causal determinism has a strong relationship with predictability. Perfect predictability implies strict determinism, but lack of predictability does not necessarily imply lack of determinism. Limitations on predictability could be caused by factors such as a lack of information or excessive complexity. \n",
"Som... |
why do vodka sodas dehydrate me? | The metabolism of alcohol requires the presence of water, and alcohol itself is a diuretic which results in less available water in your body.
Edit: To expand on this, the amount of water in your mixed drink is probably insufficient to hold off dehydration after your body has processed the alcohol. Everyone has an in... | [
"In some countries, black-market or \"bathtub\" vodka is widespread because it can be produced easily and avoid taxation. However, severe poisoning, blindness, or death can occur as a result of dangerous industrial ethanol substitutes being added by black-market producers. In March 2007 in a documentary, BBC News U... |
why when running on a treadmill usually i'm really tired at 15 min mark, almost dead at 20 min, and ok at 30 min mark ? | It actually comes from where your body gets it's energy from. For the first 15-20 minutes your body is burning it's glycogen storage which comes from sugar. After your body has run out of its primary source of energy it runs on fumes until your body starts burning your fat storage. This doesn't kick in until around tha... | [
"BULLET::::- Treadmill training – Many treadmills have programs set up that offer numerous different workout plans. One effective cardiovascular activity would be to switch between running and walking. Typically warm up first by walking and then switch off between walking for three minutes and running for three min... |
where did the term "fired" originate from? | [Etymology Online](_URL_0_) says it is recorded by 1885 (with out; 1887 alone) in American English. This probably is a play on the two meanings of discharge (v.): "to dismiss from a position," and "to fire a gun," influenced by the earlier general sense "throw (someone) out" of some place (1871). To fire out "drive out... | [
"The term \"feu\" (French for \"fire\" from the Latin \"focus\" meaning \"hearth\") meant, especially in the Middle Ages, the hearth, first in the strict sense (the place where the fire burns) and figuratively: the family home (cf. the expression \"without fire or place\") or the family itself. Very quickly, it was... |
What rank would a soldier have to be to avoid going 'over the top' in WWI? | That's a very interesting question, and relates a lot to a common perception that, once a certain level of authority is reached, the individual is less likely to participate in combat.
That is a very generalised view, of course, and as such not entirely correct. An army is a very rigid organization and must be tightl... | [
"BULLET::::- Many of the generals of World War I had experience in combat, but only from the days before trench warfare became widespread. Because of this, officers lacked the experience that in the past had made it viable to command troops from a distance.\n",
"During World War II, he served in the Royal Artille... |
how do some people become the mod of dozens of subreddits? | You'd have to ask the people who made the decision to add them, we don't know. The thought process for each individual mod invite was probably different.
I'm not sure but it's also possible that they did stuff like CSS work. There are some people who do design and CSS stuff for lots of subreddits so they have mod powe... | [
"Subreddits are overseen by moderators, Reddit users who earn the title by creating a subreddit or being promoted by a current moderator. These moderators are volunteers who manage their communities, set and enforce community-specific rules, remove posts and comments that violate these rules, and generally work to ... |
What was the video-recording format in the USSR/Ex-socialist countries ? Was there an equivalent to VHS ? | I'm not an expert on The Soviet Union but I have a strong interest in and experience with tech. So a Soviet expert may be able to add a lot to the discussion. But to quickly answer your main question, the main format used popularly in the USSR was VHS and the VCR.
There were other forms of magnetic recording devices ... | [
"The first video cassette recorder (VCR) to become available was the U-matic system, released in September 1971. U-matic was designed for commercial or professional television production use, and was not affordable or user-friendly for home videos or home movies. The first consumer-grade VCR to be released was the ... |
; why can't they just give the 12 boys and the football coach who were found in the cave in thailand oxygen masks so they can swim out? why do they need to teach them to dive or wait for the flood to recede? | There's a lot more to diving than just putting on a mask and swimming. For example, if one of the boys gets scared and holds his breath, then ascends, his lungs could rupture quite easily. They need to make sure that the boys can dive safely before they can use that as an escape method. | [
"On 23 June 2018, a group of twelve boys aged between 11 and 16, who went to explore Tham Luang Nang Non with their assistant football coach, aged 25, went missing. The group was found 10 days later. They were part of a local junior football team. The cave they entered became flooded. Thai Navy SEAL divers had been... |
- why is it so hard for companies doing political surveys to actually predict the elections? | Really? The _vast_ majority of polling is very accurate - we just only pay attention to it in the few situations where the polling was "wrong".
Polling is difficult because you are trying to take a small sample of people and extrapolate what you learn from them to a population as a whole. Ensuring that the sample is... | [
"In politics it is common to attempt to predict the outcome of elections via political forecasting techniques (or assess the popularity of politicians) through the use of opinion polls. Prediction games have been used by many corporations and governments to learn about the most likely outcome of future events.\n",
... |
why is human diet so complex? | A big part is just convienece and choice. Animals with "higher" capacity for reason can figure out optimal ways to get food and therefore the option to be picky.
Most animals don't have the range primarily because they're both evolved to live in a certain area and they have a lower count of things that they're require... | [
"Humans are omnivorous, capable of consuming a wide variety of plant and animal material. Varying with available food sources in regions of habitation, and also varying with cultural and religious norms, human groups have adopted a range of diets, from purely vegan to primarily carnivorous. In some cases, dietary r... |
What killed off the mega fauna? | Traditionally this has been ascribed either to the influence of humans on the environment or climate change, although occasionally disease has been tossed around as a hypothesis. Lately, many scientists have been siding with the climate change view.
[This study suggests otherwise.](_URL_0_) It would appear from glob... | [
"During the American megafaunal extinction event around 12,700YBP, 90genera of mammals weighing over became extinct. The extinction of the large carnivores and scavengers is thought to have been caused by the extinction of the megaherbivore prey upon which they depended. The cause of the extinction of the megafauna... |
ip addresses, subnet masks and why some ip addresses can see others on the same network? | An IPv4 address is just 4 bytes; each number between the dots is in a range of 0 to 255.
Take 192.168.60.1
In binary that's 11000000.10101000.00111100.00000001.
Now take a subnet like 255.255.224.0
In binary that's 11111111.11111111.11110000.00000000
Notice how all of the bits are together? The part of the address t... | [
"Today, IP addresses are associated with a subnet mask. This was not required in a classful network because the mask was implied by the address itself; Any network device would inspect the first few bits of the IP address to determine the class of the address and thus its netmask.\n",
"The term \"subnet mask\" is... |
When accelerating close to c, the universe appears to contract. We see the universe as expanding. Is it possible that this is some related phenomenon and that the universe isn't actually expanding? | No, these are two different phenomena (which are, by the way, both accounted for in the mathematics, so aren't being mistaken for one another!). Two observers who are moving at different speeds will measure lengths differently - this is what you're referring to with contraction - but there's no such set-up in cosmology... | [
"Since the Hubble \"constant\" is a constant only in space, not in time, the radius of the Hubble sphere may increase or decrease over various time intervals. The subscript '0' indicates the value of the Hubble constant today. Current evidence suggests that the expansion of the universe is accelerating (\"see\" Acc... |
is space observation in real time? | everything you see is delayed. you seeing the sun is 8 minutes delayed. you watching the moon is 1.3seconds delayed. you looking at jupiter yesterday was 35-52minutes delayed. you looking at the North star 323 YEARS delayed. when you look thru a telescope at andromeda galaxy, you're looking 2.25 million years dela... | [
"In each reference frame, an observer can use a local coordinate system (usually Cartesian coordinates in this context) to measure lengths, and a clock to measure time intervals. An event is something that happens at a point in space at an instant of time, or more formally a point in spacetime. The transformations ... |
Are there any cells in the human body that don't need oxygen? | Red blood cells! It actually makes quite a bit of sense, because red blood cells exist in order to transport oxygen, and if they required oxygen, they would be much less efficient in that endeavor. | [
"Oxygen is needed by almost all organisms for the purpose of generating ATP. It is also a key component of most other biological compounds, such as water, amino acids and DNA. Human blood contains a large amount of oxygen. Human bones contain 28% oxygen. Human tissue contains 16% oxygen. A typical 70-kilogram human... |
What were the different techniques used for making swords across different cultures and time periods? | You're not the only one who loves swords! I was just saying the other day how much I miss the old *Highlander* TV series, but anyway... here's my quick round-up of posts discussing sword-making techniques. If anyone remembers any more, add the link as a reply & we'll create an entry in the "popular questions" wiki. -... | [
"Italian martial arts is the use of weapons (swords, daggers, walking stick and staff). Each weapon is the product of a specific historical era. The swords used in Italian martial arts range from the gladius of the Roman legionaries to swords which were developed during the renaissance, the baroque era and later. S... |
why do cities restrict the maximum height of structures? | There's quite a few reasons.
* Higher buildings mean a denser downtown core, causing greater traffic and possibly pollution issues as people come to work from bedroom communities and search for a place to park. So unless you have good public transport (which can be quite expensive to build if not in place already), co... | [
"Building height: 2.5 m (8' +/-) to 7.5 m (24' +/-) is common. Height is primarily limited by the capability of the wall panel to support the wind load. Height may be limited in narrow buildings due to shear capacity limit in the gable endwalls.\n",
"Among the restrictions in force within the zone is a ban on the... |
why are the soles of our feet so sensitive if they’re the main (and often only) point of contact with the ground? | Most likely because you wear shoes which keep your feet baby soft.
My kids go barefoot a lot and can walk across gravel without a problem. | [
"The soles of the feet are extremely sensitive to touch due to a high concentration of nerve endings, with as many as 200,000 per sole. This makes them sensitive to surfaces that are walked on, ticklish and some people find them to be erogenous zones.\n",
"The sole is a sensory organ by which we can perceive the ... |
Did 13th century English knights fight on foot? | This answer focuses on the Anglo-Norman period, so earlier than the 13th century. But since OP was interested in English knights fighting on foot before the 14th century, I guess this will still be of interest.
In "Warfare under the Anglo-Norman Kings 1066-1135", Stephen Morrillo argues that combined arms tactics ... | [
"Many knights during Medieval battles fought on foot. Attacks would be carried out on horseback only under favorable conditions. If the enemy infantry was equipped with polearms and fought in tight formations it was not possible to charge without heavy losses. A fairly common solution to this was for the men-at-arm... |
how is a modern minted coin ever worth more than its face value, isn't that exactly what money is a guarantee that you money will be what it says it's worth? | ....an official currency coinage is only ever worth exactly its face value.
are you thinking about those tv commercials for gold clad coins? those coins are produced by a company named National Mint or something stupid like that. those are collector scams. they're not worth anything. | [
"Coins of the United States dollar (aside from those of the earlier Continental currency) were first minted in 1792. New coins have been produced annually and they make up a valuable aspect of the United States currency system. Today, circulating coins exist in denominations of 1¢ (i.e. 1 cent or $0.01), 5¢, 10¢, 2... |
In what year and battle did the last recorded charge of knights in heavy armor occur? What conflict last saw widespread use of knights in heavy armor? | If you by "knights" mean armoured cavalry consisting solely of noblemen, then the charge of the Polish crown army consisting of mostly [Polish winged hussars](_URL_0_), although they had stopped wearing the wings at that time, in the Battle of [Kliszow 1702](_URL_1_). The Polish cavalry threw the Swedish cavalry into d... | [
"One of the greatest distinguishing marks of the knightly class was the flying of coloured banners, to display power and to distinguish knights in battle and in tournaments. Knights are generally \"armigerous\" (bearing a coat of arms), and indeed they played an essential role in the development of heraldry. As hea... |
Another military or logistics question, how does an army pass a mountain, whether it's supposedly impassable or passable? | They (typically. Some people tried some crazy things) just went through known passes, which is why mountains are such great natural defenses. If there are only a small number of passes the defending army knows exactly where their enemy is coming through and can wait for them. Many mountain passes (esp. high mountain pa... | [
"For the crossing of the mountains, the Army was divided into two main columns, the first, commanded by Captain General San Martín and supported by Brigadier Major Miguel Estanislao Soler and Brigadier Bernardo O'Higgins, would take the Los Patos Pass and the second, commanded by Colonel Juan Gregorio de las Heras,... |
how does a pro gamer make a living after he / she retires? | It's a bit of a tough question to answer as the pro gaming industry hasn't delivered that many retirements so far.
However, if they follow a gathering based on not just their skill, but also their personality, they could complete a full career by Twitch (subscriptions, ads, donations) and YouTube (ads, sponsorships, P... | [
"In Career mode, the game puts the player in responsibility of a workshop where they must complete tasks that involve modifying pre-built computers, (e.g. removing viruses, adding new parts) or outright building a brand new computer to earn in-game cash, which can be spent on purchasing brand new parts, including c... |
how do spam telemarketers make money since almost everyone just hangs up? | With VOIP and cheap offshore labor, it costs virtually nothing to make those calls - partly *because* no one answers, or hangs up immediately. If you make 10,000 calls - that's every number in an exchange - and get three or four bites, you've made money. | [
"BULLET::::- Telemarketing fraud takes a number of forms; much like mail fraud, solicitations for the sale of goods or investments which are worthless or never delivered and requests for donations to unregistered charities are not uncommon. Callers often prey upon sick, Disability and elderly persons; scams in whic... |
since inflammation in the body causes numerous fatal diseases(cancer,heart disease, etc.),why can't we just pop a few nsaids like ibuprofen every day and be on our healthy way? | Taking too many NSAIDs gives you stomach ulcers for starters. There's lots of side effects to antiinflammatories. | [
"Inflammation has many possible causes, including irritation by environmental substances, physical trauma, and infection such as bacterial, viral, or fungal. Some of these infections are sexually transmitted diseases.\n",
"Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, can cause f... |
How did the Roman people handle military defeats? | How would we know what an "average citizen" thought? Every text we have is produced by the elite class. Whether people lost friends or family is impossible to know in the specifics.
We do know that military disaster did not affect the political careers of the generals involved. Rosenstein in *Imperatores Victi* dem... | [
"Rome was a war-faring nation and was accustomed to setbacks. However, the recent string of defeats ending in the calamity at Arausio was alarming for all the people of Rome. The defeat left them not only with a critical shortage of manpower and lost military equipment, but also with a terrifying enemy camped on th... |
the difference between iphone and android, and the pro's and con's of each. | Things Android phones can do *without* being rooted (the same level of permission you currently have on the iPhone):
* Change the keyboard input. [8pen](_URL_1_), [SwiftKey](_URL_0_), and [Swype](_URL_9_) are some good examples.
* Use any appstore or download apps directly from web pages. The [Amazon AppStore](_URL_1... | [
"The iPhone runs an operating system known as iOS (formerly iPhone OS). It is a variant of the Darwin operating system core found in macOS. Also included is the \"Core Animation\" software component from Mac OS X v10.5 Leopard. Together with the graphics hardware (and on the iPhone 3GS, OpenGL ES 2.0), it is respon... |
Considering all types of movement we're subjected to, how fast are we actually traversing through space at any given point in time? | what is the reference point?
this question is asked all the time and it's always the same..
1. Do a search this has been asked before
2. What exactly are we calling our fixed reference point? (the entire universe is in flux)
| [
"With current technology severely limiting the velocity of space travel, however, the differences experienced in practice are minuscule: after 6 months on the International Space Station (ISS) (which orbits Earth at a speed of about 7,700 m/s) an astronaut would have aged about 0.005 seconds less than those on Eart... |
why does spain have strong, independent cultures (i.e. basque, catalonia) while other european nations seem to be more culturally and linguistically uniform? | While I don't disagree with your question, let me find you some examples which invalidate it:
- Belgium is part French part Dutch, different languages, different traditions, different cultures.
- Yugoslavia, but that was only a stable country under Tito.
- Turkey and its Kurdistan part.
- UK (or was it GB?) and Sco... | [
"However, some traits of the Spanish spoken in Spain are exclusive to that country, and for this reason, courses of Spanish as a second language often neglect them, preferring Mexican Spanish in the United States and Canada whilst European Spanish is taught in Europe. Spanish grammar and to a lesser extent pronunci... |
why do guys insist on sending unsolicited dick pictures. does that ever really work? | Men are very visual creatures, and quick to arouse. A man can go from no arousal to immediately turned on just with a quick flash of a girl's boobs. As a result of this nature, many men don't grasp that women don't work the same way, and aren't interested much in seeing a dick unless already aroused.
Combine that with... | [
"\"Snuff\" follows three men who are waiting to immortalize themselves into pornography history as they wait to bed Cassie Wright, a former porn queen who has fallen into harder times. Each chapter follows a different guy (Mr. 600, Mr. 72, and Mr. 137), as well as Sheila, the female wrangler who dictates who is the... |
how did early man manage to drink the recommended 2 litres of water a day without access to clean water and remain strong enough to maintain his active lifestyle? | The recommended two litres of water a day is junk science invented by drinks manufacturers to sell more products. Actual scientists say you should drink when thirsty, and not drink when not thirsty (unless you are sick or actually dehydrated).
Clean water was difficult to find, and at first humans settled wherever the... | [
"A typical person will lose minimally two to maximally four liters of water per day under ordinary conditions, and more in hot, dry, or cold weather. Four to six liters of water or other liquids are generally required each day in the wilderness to avoid dehydration and to keep the body functioning properly. The U.S... |
Does smoke have weight? | Smoke has weight, yes, but that experiment is no way to find it. For example, try it with a piece of magnesium instead of a cigarette. If you burn magnesium, it gives off some smoke, and at the end the ashes are actually **heavier** than the original piece of magnesium. How? Burning is just rapid oxidation, and what's ... | [
"Cigarette smoking for weight loss is a weight control method whereby one consumes tobacco, often in the form of cigarettes, to decrease one's appetite. The practice dates to early knowledge of nicotine as an appetite suppressant.\n",
"There is much controversy concerning whether smokers are actually thinner than... |
how do you perform cpr and give compressions to a person who has fractured his chest bones? | In a situation when a person actually needs CPR a beating heart takes precedence over anything else even a fractured sternum/ribs. if the ribs puncture your lung and give you a pneumothorax, they can still fix you up later, but if the heart stop beating only for 5 minutes your brain cells will start to become necrotic ... | [
"BULLET::::- Cardiopulmonary Resuscitation (CPR) A series of chest compressions and ventilations that try to circulate blood containing oxygen throughout the body to vital organs in an attempt to resuscitate a victim. A lifeguard performing CPR on an adult should use two hands on the chest, with the ring finger of ... |
Why did the Japanese attack the United States to bring the US into WW2? Were they completely the aggressors or had some US policy given them reasons to attack? | For about 40 years the US and Japan had been on a collision course. A whole host of factors made it so that the nations and populations felt each other was a natural foe, and that when war came it would be particularly brutal.
To go through a few:
1. Residual Colonialism clashing with Japan's desire to make good its... | [
"In late 1941, Japan's government, led by Prime Minister and General Hideki Tojo, decided to break the US-led embargo through force of arms. On December 7, 1941, the Imperial Japanese Navy launched a surprise attack on the American fleet at Pearl Harbor, Hawaii. This brought the US into World War II on the side of ... |
how did we figure out that burning rocks would make metal? | Metal working is *way* past caveman times.
We figured out fire, and we figured out how to make *hot* fire (which we needed to make strong pottery, which we needed for storage because we figured out agriculture which, incidentally, meant we needed to figure out writing).
A lot of this is, necessarily, speculative, b... | [
"The traditional method of cracking rock was fire-setting, which involved heating the rock with fire to expand it. Once the rock was heated by fire it was quenched with water to break it. Fire-setting was one of the most effective rock breaking methods until 1867 when Alfred Nobel invented dynamite.\n",
"The cons... |
How did gunpowder weapons change siege tactics? | They ended up not changing the strategic nature of siege warfare that much at all, except perhaps making the defender even stronger then they had been in previous centuries (how much so varies). Siege tactics, however, changed much more - but less than you'd expect.
There was a brief period from about the late 14th ce... | [
"The introduction of gunpowder affected the conduct of war significantly. Though employed by the English as early as the Battle of Crécy in 1346, firearms initially had little effect in the field of battle. It was through the use of cannons as siege weapons that major change was brought about; the new methods would... |
Palestine to Israel | Do you mean, why did the State of Israel call itself “Israel” and not “Palestine”? The end of the British mandate on 14 May coincided precisely with the declaration of the State of Israel, which was made that evening. A few minutes later the United States recognized Israel. Recognition from other countries would arrive... | [
"The League of Nations assigned Palestine as a mandate to the UK in 1920. The British tried, but failed to stop large-scale Jewish immigration into the mandate. Britain returned it to UN control in 1947 and the UN divided Palestine into a Jewish state and an Arab state. Israel came into existence on May 14, 1948, f... |
If measurement causes the wavefunction to collapse, and everything is constantly interacting with everything else in the universe via gravity, why haven't all wavefunctions collapsed all the time? | Crudely, wavefunction collapse means the following. You allow your quantum system S to interact with a set of degrees of freedom M. The interaction entangles the state of S with the state of M, so that the probability distribution of some observable OS of S are correlated with observable OM of M. But perhaps you don't ... | [
"The measurement problem in quantum mechanics is the problem of how (or \"whether\") wave function collapse occurs. The inability to observe such a collapse directly has given rise to different interpretations of quantum mechanics and poses a key set of questions that each interpretation must answer.\n",
"The clu... |
glass is not biodegradable, and will perhaps take even longer to decompose than plastic. why isn't it made out to be as big of an issue as plastic? | I believe that the answer lies in the fact that, if you crush up glass to extremely fine fragments, it is essentially sand. Plastic, as it breaks down, continues to float, pollute, and also mimics small water-borne organisms that larger organisms feed upon. Broken glass (sand) sinks, and essentially returns to the life... | [
"This composition of bioactive glass is comparatively soft in comparison to other glasses. It can be machined, preferably with diamond tools, or ground to powder. Bioglass has to be stored in a dry environment, as it readily absorbs moisture and reacts with it. Bioglass 45S5 is the first formulation of an artificia... |
what is net nuetrality? what is being for it? against it? do we have it? trying ti get it? | John Oliver made a video a few years back and one weeks ago that touches on the subject well. Basically with net neutrality, everybody's internet speed gets treated equally regardless of what websites, browsers, etc. you use. | [
"Network neutrality (also net neutrality, Internet neutrality, or net equality) is the principle that Internet service providers and governments should treat all data on the Internet equally, not discriminating or charging differentially by user, content, site, platform, application, type of attached equipment, or ... |
If autonomous cars become the norm, how much time and gas would we save on a typical weekly commute? | I can't answer our question, but I can add some more sources of waste that would be eliminated by self-driving cars.
In theory, you would not longer need to stop at intersections. The computer algorithm could very quickly work out a way to get everyone through [with nobody stopping](_URL_0_).
In cases where the road... | [
"Manually driven vehicles are reported to be used only 4–5% of the time, and being parked and unused for the remaining 95–96% of the time. Autonomous vehicles could, on the other hand, be used continuously after it has reached its destination. This could dramatically reduce the need for parking space. For example, ... |
considering how contagious vomiting bugs are like norovirus, why aren’t we always sick with them? | Most extreme pathogens are caught early by food manufacturers. All of them are required to have up to date HACCP plans, food safety plans, and as of 2018 putting more emphasis on CoA of raw materials and doing due diligence on them. Check out the recalls. Almost all of these are 100% voluntary and require a lot effort... | [
"Noroviruses are transmitted directly from person to person (62–84% of all reported outbreaks) and indirectly via contaminated water and food. They are extremely contagious, and fewer than twenty virus particles can cause an infection (some research suggests as few as five). Transmission can be aerosolized when tho... |
why are credit cards and credit so important? what's wrong with just a debt card? | Debit cards are fine, you just don't build credit with them. You're using cash you actually have in an account, as opposed to using a credit line.
Credit is important because at some point in life, you will invariably need money you don't have. For example, you may need to take out a loan for a house, finance a car, e... | [
"Declines in credit card debt are often misinterpreted because they fail to include information about charge-offs. The possible causes for a decline in credit card debt are consumers paying down their debt, credit card companies writing charged-off debt off their books, or a combination of the two. Inclusion of cha... |
Does pollen carry or assist the spread of illness? | Pollen can act as a significant vector for viruses (_URL_0_ you can only see the abstract, but that's enough to know that pollen is a viral vector), however pollen doesn't actually increase the amount of pathogenic particles leaving someone with a transferable disease unless they are allergic. | [
"The pollen which causes hay fever varies from person to person and from region to region; generally speaking, the tiny, hardly visible pollens of wind-pollinated plants are the predominant cause. Pollens of insect-pollinated plants are too large to remain airborne and pose no risk.\n",
"Dunbar devised techniques... |
How did scientists recreate the 1918 Influenza Virus? | Scientists were able to determine the genetic sequence of the 1918 virus using samples from a woman who had died of the virus and was buried in permafrost. Then, they used the sequence to rebuild the virus, likely by expressing the genome within a cell, which would produce viral proteins that assembled into infectious ... | [
"In early 2004, David Lipman, Lone Simonsen, Steven Salzberg, and a consortium of other scientists wrote a proposal to begin sequencing large numbers of influenza viruses at The Institute for Genomic Research (TIGR). Prior to this project, only a handful of flu genomes were publicly available. Their proposal was ap... |
what does hydrogen peroxide do to earwax chemically that makes it easier to remove? | It doesn't do anything chemically to the earwax, other than possibly diluting it. It works mechanically. The bubbles help loosen the wax. The bubbles are caused by an enzyme called catalase that exists in the dead skin cells in the wax. This enzyme rapidly breaks down the hydrogen peroxide, releasing bubbles of oxygen.... | [
"Hydrogen peroxide - urea is mainly used as a disinfecting and bleaching agent in cosmetics and pharmaceuticals. As a drug, this compound is used in some preparations for the whitening of teeth. It is also used to relieve minor inflammation of gums, oral mucosal surfaces and lips including canker sores and dental i... |
growing plants indoors with non-solar light...help understanding plant needs / physics | Hahaha, c'mon man, just say it. "I'm growing pot, help plz?"
Even if you aren't though, you might just want to go to /r/trees and ask for growing tips. Same function really. | [
"When planning an indoor garden it is important to choose plants with light requirements that are conducive in homes. To maximize a plants sun exposure, place it in a room that receives high amounts of natural light. Artificial lights are an alternative if the natural lighting in a room is insufficient, and they ca... |
flight, how does it work? | Ever stuck your hand out a car window and tilted it? You feel a force pushing your hand up or down, this is Lift. Lift counteracts Weight from gravity and enables flight.
While the shape of the wing provides some lift, the majority of it comes from the angle that the wing is going into the wind at (angle of attack).... | [
"Flight is the process by which an object moves through an atmosphere (or beyond it, as in the case of spaceflight) without contact with the surface. This can be achieved by generating aerodynamic lift associated with propulsive thrust, aerostatically using buoyancy, or by ballistic movement.\n",
"Flight is the p... |
how does fat and energy work? how is it that you burn fat by exercising, but you can have fat and still be out of energy. if i just stop eating, why isn't it that i can be full of energy until my body is out of fat? | This will be a little complicated.
Fat is energy, but it's not immediately usable as energy; since cells are the smallest living unit, fat has to be broken down into parts that the cells can use before it is actually usable. Of course, breaking down molecules takes time, as well.
Breaking down the fat releases the us... | [
"Adipose tissue, commonly known as fat, is a depository for energy in order to conserve metabolic homeostasis. As the body takes in energy in the form of glucose, some is expended, and the rest is stored as glycogen primarily in the liver, muscle cells, or fat.\n",
"The body's primary source of energy is glucose;... |
how does accutane exactly work, what does it do with the body system, and why do results vary from person to person? | The Accutane molecule is similar in shape to Vitamin A. It stops sebaceous glands from working. Think of it as turning off the faucet that pumps the gunk into the acne. It doesn't work for everyone because it doesn't work for every time of acne. It works best for the big nodular acne, because that is mostly caused by o... | [
"The substance acts on mucus membranes, restoring the physiological clearance mechanisms of the respiratory tract (which play an important role in the body’s natural defence mechanisms) through several mechanisms, including breaking up phlegm, stimulating mucus production, and stimulating synthesis and release of s... |
What really happened in melee combat? | It really varies wildly based on culture, time, technology, organization, numbers, etc. Despite being from a post-gunpowder era, I feel you might be interested in a clash of pikes.
Drawing from my study, the early 16th century, if serious combat was joined it was likely to be a clash of equally matched pike formations... | [
"Melee combat is split into two phases. In the first phase, the player approaches an enemy and attempts to punch them, as with most beat 'em up games. If the player successfully hits the enemy, the game enters attack mode. If the player misses and is instead attacked themselves, the game enters defense mode. Both m... |
What burns during re-entry? | There is not burning from reentry, but heat to the point where the air becomes ionized and a plasma, and the material is red hot and begins to vaporize.
What is occurring is shock heating, or heat due to change in pressure. It is known that when a gas expands, it cools, and in the same way, when it is compressed it h... | [
"The most important first action is to stop the burning process. The source of the burn should promptly be removed (or the patient removed from the source). If the person is on fire, he/she must be told to stop, drop and roll, or extinguish the fire by covering them with heavy blanket, wool, coat, or rug. Burning c... |
how are there different "types" of spicy sensations from eating spicy food? | Because there are different compounds interacting with different receptors.
Peppers have capsaicin, which triggers the same receptors as hot temperature receptors.
Wasabi and mustards have isothiocyanates, a different compound. They are also short lived due to not being oily and volatile, meaning they can easily be wa... | [
"Gustatory sweating refers to thermal sweating induced by the ingestion of food. The increase in metabolism caused by ingestion raises body temperature, leading to thermal sweating. Hot and spicy foods also leads to mild gustatory sweating in the face, scalp and neck: capsaicin (the compound that makes spicy food t... |
How is it that humans can learn vocal language to virtually perfect speech yet still be illiterate? | Most of this is because the mapping of symbols on the page to sounds is arbitrary. When speaking you're mapping sounds to meaning. This is something you brain has specifically evolved to handle.
For written text we've invented some arbitrary symbols, we've decided that they map to specific phonemes (or they map in a c... | [
"One of the fundamental problems in the study of speech is how to deal with noise. This is shown by the difficulty in recognizing human speech that computer recognition systems have. While they can do well at recognizing speech if trained on a specific speaker's voice and under quiet conditions, these systems often... |
how do furnaces work? | fire from natural gas (or whatever the gas source is) being pushed through the vents via a blower fan | [
"An industrial furnace is an equipment used to provide heat for a process or can serve as reactor which provides heats of reaction. Furnace designs vary as to its function, heating duty, type of fuel and method of introducing combustion air.\n",
"The furnace is initially loaded with the material to be fused, whic... |
Would it be possible for Jupiter and/or Saturn to ignite? | If you did mean set on fire as in a spark causing the hyrdrogen to ignite, no. Oxygen is required for hydrogen to combust, and the composition of Jupiter as far as we're aware contains only a very small amount oxygen.
Also although not a very scientific approach, considering that it's 4.5billion years old now, if it w... | [
"BULLET::::- In the anime \"Heroic Age\", Jupiter is destroyed when a high-powered energy gun is used to knock the moon Io out of orbit. Io plummets into the atmosphere and ignites it, and intervention by the Silver and Bronze fleets leads to a cataclysmic explosion.\n",
"BULLET::::- \"Heroic Age\" (2007), anime.... |
steam trading cards, gems, mystery cards, etc... | **Steam Trading Cards are virtual cards earned by playing games on Steam. Sets of cards can be turned into game badges and tradable Steam community items.**
**Once you’ve collected a set of cards you can craft them into a game badge. Like the current badges, they are tied to your account and are shown on your profile.... | [
"Steam Trading Cards are a digital commodity issued by Valve Corporation for use on its digital distribution platform, Steam. Steam Trading Cards are a non-physical analogue of conventional trading cards, which are periodically granted to Steam users for playing games, fulfilling tasks, or by random chance. Cards c... |
how is your normal facial expression decided? | Genetics, Stressers and muscle memory.
Genes is the first thing, you can't change these this can cause things from your skin, your face shape and where fat wants to reside.
Stressers like age, sun damage and sleep deprivations as well as allergic reactions affect the look of your face beyond genetics.
And muscle ... | [
"Facial expressions are vital to social communication between humans. They are caused by the movement of muscles that connect to the skin and fascia in the face. These muscles move the skin, creating lines and folds and causing the movement of facial features, such as the mouth and eyebrows. These muscles develop f... |
How much of their forces did germany devote to the eastern front in WWI? | By February 1916 the Germans had c. 50 divisions on the eastern front; by September of that year, the number had risen to c. 70 divisions. When the Treaty of Brest-Litovsk was signed, there were 1.5 million German troops in the East, of which 500 000 were shifted to the Western Front by the spring of 1918, starting alr... | [
"On the Eastern Front the volunteers and conscripts in the \"Ostlegionen\" comprised a fighting force equivalent of 30 German divisions by the end of 1943. By mid-1944 upwards of 600,000 troops of the Eastern Legions/Troops were assembled under the command of General Ernst-August Köstring, stemming mostly from the ... |
hypodermic needle model. | The magic bullet theory is that for the every person in the world when effected by a specific message will have a specific reaction.
The general concept was that if a person was presented with advertising or propaganda they would react in a specific way as a passive participant in the process, being immediately effect... | [
"The hypodermic needle model (known as the hypodermic-syringe model, transmission-belt model, or magic bullet theory) is a model of communication suggesting that an intended message is directly received and wholly accepted by the receiver. The model was originally rooted in 1930s behaviorism and largely considered ... |
[Human Body] Is it possible to feel pain that is not actually there? | Yes. The simplest example would be phantom limb syndrome. There are no nerves to stimulate in this situation. Phantom limb is considered neuropathic pain, but we still don't quite fully understand the mechanism behind it.
Beyond that there are disorders that can lead to allodynia. This is when you experience pain from... | [
"Pain is an aversive sensation and feeling associated with actual, or potential, tissue damage. It is widely accepted by a broad spectrum of scientists and philosophers that non-human animals can perceive pain, including pain in amphibians.\n",
"There are two main types of pain that we experience in our bodies: p... |
why do some things need 4 aaa batteries instead of fewer number of a stronger battery? example: why use 4 aaa when one might be able to use 2aa. | AA are not "stronger" than AAA, they just have more power reserve.
They both put out the same voltage though AA can probably do so at a higher amperage if required.
By arranging the batteries in different combinations of parallel and series you can get different combinations of "power" (voltage) or battery life (m... | [
"AAA batteries are most often used in small electronic devices, such as TV remote controls, MP3 players and digital cameras. Devices that require the same voltage, but have a higher current draw, are often designed to use larger batteries such as the AA battery type. AA batteries have about three times the capacity... |
Would a black hole really appear as a sphere like in Interstellar? | The science advisor for interstellar was Kip Thorne, who just shared the Nobel Prize in Physics for his modelling of the gravitational waveform emitted by two merging black holes. He had the movie studio run a relativistic ray tracing code to generate the images of the black hole (given a small accretion disk in place ... | [
"For non-rotating black holes, the photon sphere is a sphere of radius 3/2 \"r\". There are no stable free fall orbits that exist within or cross the photon sphere. Any free fall orbit that crosses it from the outside spirals into the black hole. Any orbit that crosses it from the inside escapes to infinity or fall... |
Would I move in opposite direction in space if I pushed smaller object then me ? | Yes. If you give the bowling ball momentum in one direction, you will have the same momentum in the opposite direction. This is the same principle that allows rockets to work: exhaust goes in one direction, rocket goes in the other. | [
"Since the object's velocity vector is constantly changing direction, the moving object is undergoing acceleration by a centripetal force in the direction of the center of rotation. Without this acceleration, the object would move in a straight line, according to Newton's laws of motion.\n",
"In physics, action a... |
Historically speaking, Ukraine wasn't where it is now. It's in what used to belong to Crimea. What's the logic behind Ukraine's placement after the fall of the USSR? | I'm no expert so I don't have any answer, but could you clarify what you're talking about a little? If I look at some easy-to-find sources (wikipedia, etc.) on the history of Ukraine, I'm not seeing anything that looks like this:
> Ukraine was in a completely different part of Europe than we think of today (That is t... | [
"From 1922 until 1991, \"Ukraine\" (also \"the Ukraine\") was the name of the territory of the Ukrainian Soviet Socialist Republic (Украї́нська Радя́нська Соціалісти́чна Респу́бліка, \"Ukrayins'ka Radyans'ka Sotsialistychna Respublika\") within the Soviet Union (annexed by Germany as Reichskommissariat Ukraine duri... |
how do cameras focus, and why does the background get blurry? | This will work better if you're nearsighted, but should work even if you're not. Look at something in the distance that's blurry because it's far away. Now squint--see how, for a little moment, it's easier to see because you're squinting? Cameras essentially focus by 'squinting' -- adjusting the lens so that the focus ... | [
"Photographs taken with this technique are characterized by blurred streaks emanating from the center of the photograph. The effect is nearly identical to a motion blur image in which the camera is traveling towards the subject. For this reason the zoom burst is typically used to create an impression of motion towa... |
why does the human body become dependant on drugs that are not natural to it? | It depends a lot on the drug as to what's happening in the body, but two general reactions is that the drug either induces a standard process in the body, or replaces a hormone in the body. In either case, the body learns to stop inducing or producing whatever process the drug supplements because it saves the body ene... | [
"Drugs (especially opioids and stimulants) can change the motivational patterns of a person and lead to desocialization and degradation of personality. Acquisition of the drugs some times involves black market activities and leads to criminal social circle.\n",
"Why do humans seek out and at times even develop ad... |
The Eagle Nebula - what would it currently look like? | Unless this is *very* recent news (i.e., the last day or so), then I don't think it's true. There hasn't been a supernova in the Milky Way for some time -- [they average at just a couple per century](_URL_0_) -- which is an interesting problem in itself.
You should be fine using the HST image. | [
"The Eagle Nebula (catalogued as Messier 16 or M16, and as NGC 6611, and also known as the Star Queen Nebula and The Spire) is a young open cluster of stars in the constellation Serpens, discovered by Jean-Philippe de Chéseaux in 1745–46. Both the \"Eagle\" and the \"Star Queen\" refer to visual impressions of the ... |
why is southern europe relatively lush compared to the deserts of north africa when they are both next to the mediterranean? | Okay, so the comments so far only are only partially correct but the main reason is persistent high pressure which results in subsidence. There is a concept referred to as a [Hadley cell](_URL_0_) which is a basic description of how the atmosphere circulates. Essentially, the equator is hot and the poles are cold. Hot ... | [
"In Europe, some Mediterranean areas have a steppe-like vegetation, such as central Sicily in Italy, southern Portugal, parts of Greece in the southern Athens area, and central-eastern Spain, especially the southeastern coast (around Murcia), and places cut off from adequate moisture due to rain shadow effects such... |
I've heard that the Ancient Romans saw large penises as a sign of barbarism. To what extent is this the case? | In general, the surviving sculptures, vases, and writings describing male beauty in the Greco-Roman world depict the ideal of beauty for men (especially young men) as being hairless, thin, athletic, and with a small penis with a tapering foreskin. Large penises are most often found on satyrs, ugly old men, and barbaria... | [
"Nonetheless, there are indications that the Greeks had an open mind about large penises. A statue of the god Hermes with an exaggerated penis stood outside the main gate of Athens and in Alexandria in 275 BC, a procession in honor of Dionysus hauled a 180-foot phallus through the city and people venerated it by si... |
why does my dog smell differently when he comes inside from the cold? | The air oxidizes the oils in his fur, changing the way it smells to us. It happens to people too. Try smelling yourself before and after you spend some time in a windy area. | [
"Dogs, as with all mammals, have natural odors. Natural dog odor can be unpleasant to dog owners especially when dogs are kept inside the home, as some people are not used to being exposed to the natural odor of a non-human species living in proximity to them. Dogs may also develop unnatural odors as a result of sk... |
What causes black holes to have an upper limit to their rotational speed? | The *intuitive* reason is that angular momentum has an associated rotational energy. This energy increases the mass of the black hole (through E = Mc^(2)).
Now, if you fix the total mass M, increasing the spin J then increases the fraction of M that is due to this rotational energy, and decreases the fraction of "norm... | [
"In this way, rotational energy is extracted from the black hole, resulting in the black hole being spun down to a lower rotational speed. The maximum amount of energy is extracted if the split occurs just outside the event horizon and if particle C is counter-rotating to the greatest extent possible.\n",
"A rota... |
How did arabic women dress during the abbasid caliphate? | The actual cultural dress? No idea. But they were definitely not dressed like belly dancers. The average Muslim woman would have covered the majority of her body other than her face, hands, and feet. Muslim males would have covered the same area except for manual laborers who might have taken their shirt off while work... | [
"Muslim Turkish-Cypriot women wore traditional Islamic headscarves. When leaving their homes, Muslim Cypriot women would cover their faces by pulling a corner of the headscarf across their nose and mouth, a custom recorded as early as 1769.\n",
"In contrast to the earlier era of the Prophet Muhammad and the Rashi... |
how can humans survive a partial beheading? | If that spinal cord isn’t cut, you won’t die instantly. Granted, you won’t live long with a severed carotid without immediate medical attention (even then it’s a crap shoot). | [
"Immurement (from Latin \"im-\" \"in\" and \"murus\" \"wall\"; literally \"walling in\") is a form of imprisonment, usually for life, in which a person is placed within an enclosed space with no exits. This includes instances where people have been enclosed in extremely tight confinement, such as within a coffin. W... |
What are the differences between a mole and a freckle? | Both are types of what are known as *melanocytic lesions* - basically areas with a greater amount of production of melanin than the rest of the skin. Melanin is the pigment that is responsible for difference in skin tone and also the colour of moles and freckles.
Melanin is produced by cells called *melanocytes*. The ... | [
"Mole-Stache (a play on mole and moustache) is an orange mole-like alien with a British accent and a yellow moustache that can be used in a variety of ways that include serving as an extra set of hands or as a makeshift propeller. While Molestache first appeared in \"Outbreak\" while Blukic and Driba were trying to... |
Do any wild organisms have a symbiotic relationship with another to babysit their young? | There are functional relationships where one species invests itself in raising the young of another, although the examples I'm familiar with are completely one-sided, which makes them parasitic and not symbiotic. Consider for instance the cuckoo, which will lay its eggs in another birds nest and just ... leave. The oth... | [
"Most sexually reproducing animals spend their lives as diploid, with the haploid stage reduced to single-cell gametes. The gametes of animals have male and female forms—spermatozoa and egg cells. These gametes combine to form embryos which develop into a new organism.\n",
"Exposed eggs are typically and readily ... |
Can a wave's wavelength be smaller than Planck length? And why? | No one knows the answer to this question.
The Planck length just represents the scale at which our current models break down, the scale at which a theory that combines gravity and quantum mechanics will be needed. What the new models that work at that scale will tell us about physics at that scale or smaller is an op... | [
"Whether objects heavier than the Planck mass (about the weight of a large bacterium) have a de Broglie wavelength is theoretically unclear and experimentally unreachable; above the Planck mass a particle's Compton wavelength would be smaller than the Planck length and its own Schwarzschild radius, a scale at which... |
if companies like samsung and apple pay (m/b)illions in "patent wars" about violating design patents, how can companies easily create identical iphone or samsung device knockoffs commonly seen on ebay and amazon? | They aren't in serious competition, for one; those are entirely different price points.
Also, China. | [
"A \"patent war\" between Samsung and Apple started when the latter claimed that the original Galaxy S Android phone copied the interfaceand possibly the hardwareof Apple's iOS for the iPhone 3GS. There was also smartphone patents licensing and litigation involving Sony Mobile, Google, Apple Inc., Samsung, Microsof... |
How would people get phone messages during the 1930's? | Not a silly question. There were two types of calls that could be made during this time: person-to-person and station-to-station. If you had a specific person you wanted to talk to you would request a person-to-person call. You wouldn't be billed for the long distance charges until that person came to the phone. This w... | [
"In the call-box system developed in 1872, a customer would ring the telegraph office for a messenger who would then speed to the customer's door to pick up a handwritten message and return to the telegraph office to have it sent electrically to its destination.\n",
"The Second World War made military use of radi... |
Why is the weight of a molecule in atomic mass units not exactly equal to the sum of the protons and neutrons? | /u/RobusEtCeleritas has a good explanation. It is also important to know that the masses of atoms are measured in amu (atmic mass units), where 1 amu is 1/12 the mass of a carbon 12 atom. This takes into account some of the binding energy that was brought up, but not every atom has the same binding energy per nucleon (... | [
"The sum of the atomic number \"Z\" and the number of neutrons, \"N\", gives the mass number \"A\" of an atom. Since protons and neutrons have approximately the same mass (and the mass of the electrons is negligible for many purposes) and the mass defect of nucleon binding is always small compared to the nucleon ma... |
What race was Attila? | Do you mean what race *would* be Attila today? Race as we know it today is an early modern construct that wouldn't have played the same role in his life, akin to saying was he a Christian or a Muslim. | [
"Attila (; fl. c. 406–453), frequently called Attila the Hun, was the ruler of the Huns from 434 until his death in March 453. He was also the leader of a tribal empire consisting of Huns, Ostrogoths, and Alans among others, in Central and Eastern Europe.\n",
"Attila grew up in a rapidly changing world. His peopl... |
why are canker sores, ingrown toenails, and splinters so excrutiatingly painful? | Hands, feet, the face, the mouth and the external genitals have a very large number of nerve endings that give a high level of the sense of touch in those parts. Other parts of the body are a lot less sensitive. Some internal organs sense no physical pain at all. It's pretty easy to see why the body has evolved this wa... | [
"They tend to be painful due to the pressure applied to the nail bed and plate. They can involve destruction of the nail bed. These lesions are not true osteochondromas, rather it is a reactive cartilage metaplasia. The reason it occurs on the dorsal aspect is because the periosteum is loose dorsally but very tight... |
What is the reason for China's relatively modest nuclear arsenal? Why is China the only nuclear weapons state to have given an unqualified security assurance to non-nuclear-weapon states? | Under the theory of nuclear deterrence, most nuclear weapons states have little reason to build beyond that quantity of warheads. It's enough to effectively destroy any country. That's one reason why most nuclear weapons states stop near the 300 mark. The US and Russia are the exception because of their massive arms ra... | [
"In 2004, China stated that \"among the nuclear-weapon states, China ... possesses the smallest nuclear arsenal,\" implying China has fewer than the United Kingdom's 200 nuclear weapons. Several non-official sources estimate that China has around 400 nuclear warheads. However, U.S. intelligence estimates suggest a ... |
monte carlo simulation and markov chain or more specifically the setting up of the data. | > BUT if you have a - day, theres a i dunno + 10% bonus that it will be a - day tomorrow too.
Then it isn't a Markov chain. A Markov chain's defining property is that the future evolution of the system depends *only* on its current state - it is "memoryless". You could still do a Monte Carlo simulation, since those... | [
"Monte Carlo simulation provides the capability, through sensitivity analysis, to identify single or chains of events. These chains of events can be identified by analyzing the correlations between the main project parameters, such as project duration or cost, and the event chains. These are called “critical events... |
What is the significance in electric and magnetic components of EM radiation being right angles to one another? | The components of the electric and magnetic fields are different in different inertial reference frames.
But they can be written in terms of an object called the [electromagnetic field tensor](_URL_0_), which is relatively straightforward to transform between frames.
From this tensor you can construct two invariant q... | [
"Both of these EMFs, despite their apparently distinct origins, are described by the same equation, namely, the EMF is the rate of change of magnetic flux through the wire. (This is Faraday's law of induction, see below.) Einstein's special theory of relativity was partially motivated by the desire to better unders... |
Is riding a bike muscle memory? | **Edit, Source:** [I am on a course to acquire one of these in Physical Education.](_URL_0_) ~~There's no way to compare it to American qualifications, so I wouldn't bother trying if I were you.~~
> If there's a corresponding track, it would have to be closer to [Advanced Placement](_URL_2_) level courses offered in... | [
"Muscle memory is a form of procedural memory that involves consolidating a specific motor task into memory through repetition, which has been used synonymously with motor learning. When a movement is repeated over time, a long-term muscle memory is created for that task, eventually allowing it to be performed with... |
what it that feeling of horrible burning when water goes up your nose when diving into a pool or just taking a shower and reaching down for something? |
The main reason why water burns when it goes up your nose is because the salinity of the water does not match the salinity of the cells in your body. The salinity of freshwater is much lower than your body, so when water gets into your nose and into your sinuses, some of the cells that line the sinus and nasal cavitie... | [
"Some warning signs that occur include pain, burning and numbness at the place of infection. Also people with the disease experience sleeplessness, headaches, irritability, difficulty swallowing and throat spasms. They may experience fear of water (hydrophobia).\n",
"Erythema ab igne (EAI), also known as hot wate... |
What are the pros and cons of HDL, LDL, and omega-3 fatty acids? (Also what are omega-3 fatty acids?) | Hi there.
After digestion, your lipids are packed into droplets known as chylomicrons. From there, they are transported to the liver and re-packaged as lipoproteins (containing cholesterol, triglycerides, fatty acid etc).
So as these lipoproteins, fresh from the liver, transport fatty acids, cholesterol and trigl... | [
"Omega-3 fatty acids are polyunsaturated fatty acids (PUFAs) that are essential for proper brain and cognitive development. They also play a large role in the production of anti-inflammatory eicosanoids, which has been shown to reduce the risk of cardiovascular disease and other inflammatory diseases. There are thr... |
how does the air stay so hot in the nighttime when the sun isn’t even out? and how is it that the sun makes the temperature only like 5-10 degrees warmer during the daytime in the summer? | The same reason the inside of an oven doesn't return to room temperature the instant you turn it off. Both the atmosphere and the ground absorb heat during the daytime. It takes time for this heat to dissipate after the sun sets. Furthermore, and this answers some of the second part of your question as well, air doesn'... | [
"BULLET::::- Due to the thin atmosphere, the temperature difference between day and night is much larger than on Earth, typically around 70 °C (125 °F). However, the day/night temperature variation is much lower during dust storms when very little light gets through to the surface even during the day, and instead w... |
When does a comet stop moving? | You can think of a comet entering our solar system as a ball rolling down a hill. As it gets closer and closer to the sun, it'll speed up more and more. When it heads away from the sun, it'll be slowing down, like a ball going uphill. This is because of the effect of the sun's gravity. It won't otherwise come to a stop... | [
"Each time a comet swings by the Sun in its orbit, some of its ice vaporizes and a certain amount of meteoroids will be shed. The meteoroids spread out along the entire orbit of the comet to form a meteoroid stream, also known as a \"dust trail\" (as opposed to a comet's \"gas tail\" caused by the very small partic... |
why is it racist to do an asian accent but not racist to to a british or an australian etc. one | If you are a white American, it is because that is the same race. Brits and Australians speak the same language as you, just with different accents. An Asian has learned your language even though it is not their native tongue, and you would be mocking them. | [
"In response to the issue, Bollywood star Amitabh Bachchan turned down an honorary doctorate from the Queensland University of Technology. Fellow Indian actor, Aamir Khan, has condemned the attacks, stating that, \"[It is] most disturbing to hear about racist attacks on Indians living in Australia. Quite a shame. W... |
why are so many of the world's greatest classic rock bands from england? what were the influences at that time and when did their rising popularity start to decline? | Two reasons.
1. The Beatles. They were HUGE, and seemingly came from nowhere. They became the most popular band in history, and inspired many small time bands and musicians in England to try and go big as well.
2. Empire. GB used to basically rule the world, and a lot of the world took up parts of British culture bec... | [
"At the same time, rock and roll was played in Britain after 1955. The British product has generally been considered less successful than the American version of the genre at the time, and made very little international or lasting impact. However, it was important in establishing British youth and popular music cul... |
Does the pull of gravity increase or decrease as you approach the center of a mass? | I assume when you say "approach the CoM", you mean drilling a borehole.
The [Shell Theorem](_URL_0_) states that it decreases. Assuming the body in question is radially uniform, the gravity at a point inside the body is equal to the gravity pull as if the mass above you (i.e. the "shell" of earth above you) didn't exi... | [
"The acceleration due to gravity depends on the gravity of the mass, which rests inside of the object. The gravity decreases at longer distance between centers of mass. The acceleration due to gravity furthermore is influenced by the rotation of the earth. As centrifugal force increases at longer earth's axis dista... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.