:And now that I've tried my best ''philosophy'', let's see what I can find in data: to start with, there's an interesting phenomenon of a pale stripe on corpses (mostly suicides) at the level of the bathtub [http://www.medline.ru/public/sudm/a2/art3-2-2.phtml] which can be postmortem, but might be weaker then. So there's some kind of surface conduction effect I'd never have guessed at which just blows all our inverse-square stuff right out of the water. [http://www.cracked.com/article_19171_5-things-that-arent-nearly-as-dangerous-as-hollywood-thinks_p2.html These guys] talking about electrons "making a beeline for the ground" likewise stand exposed. And [http://articles.latimes.com/1997/aug/08/local/me-20507 this article] describes a tragic case where TWO girls were killed when a hairdryer fell into a bathtub, which argues very strongly against a "lucky path through the heart" explanation. Lee Harvey Oswald would have been hard pressed to drill through ''two'' hearts in a shot. The article also says that fatalities from dropped hairdryers averaged 18 a year. But... the one thing these statistics leave out is how many times somebody did the same unsafe thing and emerged shaken but uninjured, so my skepticism is not totally defeated, but it definitely will maintain a more respectful distance in the future. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 14:00, 13 August 2016 (UTC)
:And now that I've tried my best ''philosophy'', let's see what I can find in data: to start with, there's an interesting phenomenon of a pale stripe on corpses (mostly suicides) at the level of the bathtub [http://www.medline.ru/public/sudm/a2/art3-2-2.phtml] which can be postmortem, but might be weaker then. So there's some kind of surface conduction effect I'd never have guessed at which just blows all our inverse-square stuff right out of the water. [http://www.cracked.com/article_19171_5-things-that-arent-nearly-as-dangerous-as-hollywood-thinks_p2.html These guys] talking about electrons "making a beeline for the ground" likewise stand exposed. And [http://articles.latimes.com/1997/aug/08/local/me-20507 this article] describes a tragic case where TWO girls were killed when a hairdryer fell into a bathtub, which argues very strongly against a "lucky path through the heart" explanation. Lee Harvey Oswald would have been hard pressed to drill through ''two'' hearts in a shot. The article also says that fatalities from dropped hairdryers averaged 18 a year. But... the one thing these statistics leave out is how many times somebody did the same unsafe thing and emerged shaken but uninjured, so my skepticism is not totally defeated, but it definitely will maintain a more respectful distance in the future. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 14:00, 13 August 2016 (UTC)
::Prolonged exposure to an electrical current can kill, even though that current is at a much lower level than would kill instantly. The case of the two girls in the bathtub is an example. For instant death to occur, it would either have to burn tissue or possibly cause the heart to [[fibrillate]], although I suspect that in the later case most people's hearts are able to "reset" on their own (we only hear about fibrillation being a problem in the small portion of cases where this reset doesn't work). However, even at low levels the nerves' actions are interrupted temporarily, and if this "temporary" is long enough to keep the heart from beating until brain death occurs (maybe 10 minutes at normal temps), then death will occur. I myself, as a kid, put my hands on a fence I didn't know was electrified, and my fists compressed around it. Had it not been the type that pulsed on and off, I wouldn't have been able to let go and might have eventually died. (I don't know if my heart was beating during the shock.) [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 15:10, 13 August 2016 (UTC)
::Prolonged exposure to an electrical current can kill, even though that current is at a much lower level than would kill instantly. The case of the two girls in the bathtub is an example. For instant death to occur, it would either have to burn tissue or possibly cause the heart to fibrillate, although I suspect that in the later case most people's hearts are able to "reset" on their own (we only hear about [[fibrillation]] being a problem in the small portion of cases where this reset doesn't work). However, even at low levels the nerves' actions are interrupted temporarily, and if this "temporary" is long enough to keep the heart from beating until brain death occurs (maybe 10 minutes at normal temps), then death will occur. I myself, as a kid, put my hands on a fence I didn't know was electrified, and my fists compressed around it. Had it not been the type that pulsed on and off, I wouldn't have been able to let go and might have eventually died. (I don't know if my heart was beating during the shock.) [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 15:10, 13 August 2016 (UTC)
== Ocular bruising from tooth extraction ==
== Ocular bruising from tooth extraction ==
Revision as of 15:11, 13 August 2016
Welcome to the science section of the Wikipedia reference desk.
The best answers address the question directly, and back up facts with wikilinks and links to sources. Do not edit others' comments and do not give any medical or legal advice.
No sources unfortunately, I read/saw an interview with Dutch swimmers/coaches during/after the last Olympics explaining some advances in training. Years ago, trainers kept time with a chronometer and watched with their eyes how their charges swam. Now, it's possible with cameras both in and out of the water and the results of these are analysed, which could explain the new records even without a special suit. Rmvandijk (talk) 09:08, 9 August 2016 (UTC)[reply]
Good question. Nobody else has tackled this post so I will. Here goes.... Some might say that they will never leave the observable universe as galaxies leave a light-trail behind. But of course, as they move away, they move away faster and faster, so the Doppler effect will cause them to move more into the infra red end of the spectrum and maybe even lower, but we will (or rather any other life form that replaces us in the distant future) will be still be able to detect them. As to the 'comoving' bit. We may only be able to see these very distant objects as they were billions of years ago, due to the speed of light taking that time to reach us and they have moved many light years on since, but then consider this. We can only see our own sun as it was 8½ minutes ago yet we still say we can observe it. Yet, that leads on to another question. Is the expansion of the universe infinite or finite. Ie, will expansion slow down and eventually stop, only then for everything to go into reverse and end up at its original point of origin to creating another big bang? Come on Stephen Hawking, you must read Wikipedia from time to time. What is the answer (if you don't answer, I might be inclined to hack your speech synthesizer and make you sound like Fenella Fielding). --Aspro (talk) 19:21, 9 August 2016 (UTC)[reply]
The observable universe is usually defined to be everything with a worldline that intersects our past light cone at any point after the last scattering time (redshift z ≈ 1100, around 400,000 years after the big bang). By this definition, nothing can ever leave the observable universe. You can see in a diagram like this one:
/\ ← later
/ \
/ \
/ /\ \ ← now
/ / \ \
/ / \ \
~~~~~~~~~~~~~~~~ ← last scattering time
that anything that intersects the past light cone of Earth at an earlier time will intersect it at a later time.
"The observable universe right now" is the intersection of those same worldlines with space at the present cosmological time. So the things in the observable universe right now are the same as the things we can see (in principle) on our past light cone.
(Technically it is more complicated than this, because of peculiar velocities relative to the Hubble flow. If you define the "observable universe right now" by the Hubble flow, rather than the actual worldlines of galaxies, then some galaxies right at the edge of the past-light-cone observable universe aren't in the "observable universe right now", and vice versa. But I think that's an unimportant detail.) -- BenRG (talk) 00:25, 10 August 2016 (UTC)[reply]
What about going the other direction, though? When will it be the case that the future-facing light cones do not meet?
(And is there a name for that? I think I've also heard that described as the "observable universe", in the context of discussions of the Big Rip, which is sometimes described as the observable universe getting smaller.) --Trovatore (talk) 00:32, 10 August 2016 (UTC)[reply]
I don't think "observable universe" is used for future light cones. In standard (ΛCDM) cosmology, the past light cone of our infinite future is an event horizon beyond which we can never see anything. That horizon eventually shrinks to a constant apparent size (a sphere with a radius of about 16 billion light years). People often describe that as the observable universe, but that's inconsistent with the standard usage. (It could be a second standard usage, but there are a lot of incorrect statements about cosmology on the web, and even in published papers, some of which are documented in "Expanding Confusion". I don't think I've heard anyone use "observable universe" in this way who I trusted to know what they were talking about.)
That horizon shrinks to a point at the Big Rip. But if the universe ends at all, the past light cone of the end of any particle's existence is an event horizon for that particle, and shrinks to a point (as past light cones do), so the fact that it happens in the Big Rip doesn't distinguish it from any other end-of-the-universe scenario. -- BenRG (talk) 17:51, 10 August 2016 (UTC)[reply]
It would be good to have a convenient name for the portion of the universe inside that horizon. I gather that you personally may be in a position at some point to have some influence on that IRL. Maybe you can work on it. 1/2 :-). --Trovatore (talk) 22:33, 10 August 2016 (UTC)[reply]
Okay, so, obviously things are more complicated than I assumed. Or maybe I just didn't explain myself well (probably likely). My understanding is that with the expansion of spacetime the relative speed between us (the observer) and UDFj-39546284 eventually becomes superluminal. At this point any light that leaves either end of this comoving distance (and heads towards the other side) can never reach the other side. At what point in the future will the relative speed between us and it caused by expansion become superluminal (thus severing the causality between any events here and there)? Melmann(talk)09:01, 10 August 2016 (UTC)[reply]
I think that's roughly what I was getting at with my question to Ben. But I'm not sure it really makes sense (or at least there may not be only a single interpretation) to talk about the "relative speed" between us and a distant galaxy, given that we don't share a common Lorentzian reference frame (happy to be corrected on that point though). However, the formulation about the future-facing light cones not meeting seems unambiguous (though of course it would be vacuous if the universe were destined to collapse eventually in a Big Crunch, but that doesn't seem to be a common opinion these days). --Trovatore (talk) 09:15, 10 August 2016 (UTC)[reply]
Superluminal recession doesn't mean much. In an open universe without a cosmological constant (which never recollapses, and contains an infinite amount of matter), you eventually see light from arbitrarily distant objects at arbitrarily late times, even though Hubble's law still holds, and says that faraway matter has arbitrarily large recessional speeds. Fundamentally, the "recessional speed" is just not very meaningful. It's not the same as special-relativistic speed, which can't exceed c.
In standard (ΛCDM) cosmology, there is an event horizon which eventually behaves something like a black hole horizon turned inside out (see my answer above). The radius of that horizon at late times is is c/H∞, i.e. the distance at which Hubble's law says that the recession speed is c in the late-time limit. This annoying fact prevents people from understanding that this isn't true in general (it isn't even true in ΛCDM at earlier times).
At any rate, in ΛCDM, for any given object that we can see, there is a last cosmological time at which light it emits will reach us, namely the time at which it crosses that horizon. I haven't done the calculation, but I think that for an object with z=10, that time is already in the past. -- BenRG (talk) 18:12, 10 August 2016 (UTC)[reply]
Also, Skylon is defined as a tensegrity. A tensegrity, of course, refers to a compression structure or any Bruce Willis movie. However, sometimes the term is used to describe structures like this, which would look the same before and after any natural disaster. So, back to the first question, helix? :) Anna Frodesiak (talk) 12:49, 10 August 2016 (UTC)[reply]
We hit on a linguistic Q, whether a portion of a thing is still called that thing. A partial circle is called a "circular arc", not a "circle". So, I would suggest that less that one revolution of a helix might be called "a partial helix". StuRat (talk) 19:04, 10 August 2016 (UTC)[reply]
The following discussion has been closed. Please do not modify it.
Is it possible to pickle my Hamster? I miss him now he's gone and I'd like to keep him but I'm told that he'll rot now he's dead. Would it be possible to keep him pickled in a Jar?
I'm not sure pickling would be the preferred method of storing a dead animal long term (have you looked into taxidermy?). If you are set on wet preservation, this article has a general overview of storing specimens. The author suggests using a fixative such as formalin followed by long-term storage in diluted isopropyl or ethanol alcohol. Basically, there's a lot of preparation involved and you can't simply put a mammal in some liquid and hope it keeps. clpo13(talk)18:38, 10 August 2016 (UTC)[reply]
Why escalator stairs' steps have sharp edges?
I imagine there must be a pretty good design reason for the sharp edges of an escalator's step. They obviously imply an extra security safety risk. So, I suppose there is a trade-off between security and something else. --Llaanngg (talk) 18:37, 10 August 2016 (UTC)[reply]
Note that the edge doesn't have to be sharp like a knife for people to hurt themselves on it; it just has to not be rounded. For example, if you trip and fall while on the moving escalator, your upper body is going to descend at least a few feet or probably more than a meter—and farther than that if it's a down escalator. Your upper body will pick up enough speed that any non-rounded edge can do injury. Also note that in order for you to be able to step off the escalator while walking forward (which is much easier to use than the old "shunt" design where you had to step off sideways), each step surface is made up of individual ribs that go under the comb plate, and each rib has its own edges. At one time those ribs might have been made of wood rather than metal, so they'd do you less of an injury if you hit them, but wooden parts on an escalator are a fire hazard. --69.159.9.219 (talk) 20:40, 10 August 2016 (UTC)[reply]
The escalators to the 8th and 9th floor of Macy's, the world's second largest store, are the original wood ones from the store's 1902 opening or so. The entire escalator is wood. It even sounds woody. It creaks constantly and the creaks and the other sounds it makes sound so extremely woody it's probably the closest thing you can ever experience to an anachronistically steampunk escalator. There are also buttloads of lit Christmas trees in the wood escalator zone after like Columbus Day. Also dozens of Santa Clauses. And hundreds of Persian carpets, books, children, burnable toys, lots of pianos and furniture and thousands of wood floorboards (though maybe not all at the same time) Sagittarian Milky Way (talk) 23:03, 10 August 2016 (UTC)[reply]
Sure, even a fall on wooden stairs can gouge your shins or whatever. But I very much doubt that it's a problem to put your hand on it. However, if I don't follow up, you'll know what happened. :( ←Baseball BugsWhat's up, Doc?carrots→ 22:20, 10 August 2016 (UTC)[reply]
Not sure how security comes in to it, but safety obviously does. However I'm pretty sure it's safety both ways. Sharp edges are obviously a safety risk due to increased likelihood of injuries from a fall or simply kicking the edge. However the design of escalators requires sharp edges. A rounded edge would mean things are likely to fall in or get caught between the step and the comb on the end plate at the top and bottom. I can't find great sources but these hint at it [3][4]. To put it a different, if you think falling on an stair edge is nasty, imagine getting your foot stuck caught and dragged when you reach the top or bottom because there's a gap between the step and the end plate due to a rounded edge. Nil Einne (talk) 19:00, 10 August 2016 (UTC)[reply]
A rounded edge would make it more likely people would slip and fall. A sharp edge sticks into rubber soles on the bottom of shoes and holds them in place better. StuRat (talk) 19:07, 10 August 2016 (UTC)[reply]
As you can see, the rounded step has less level surface area on which to stand, making it more likely people will slip off. You could counter this effect by making the steps larger, but that has down sides too. As far as the advantage of sharp metal for holding a shoe in place, do an experiment where you step on a sewer grating (the kind with an open grid) and try to slide your feet. Now do the same thing on the pavement. I bet you find your shoes move easier on level pavement. This is because rubber extends down between the grates and physically hits the grating. The hotter the shoes and the softer the rubber, the more effect this will have. A pattern on the shoes soles makes this more noticeable, too. StuRat (talk) 03:23, 11 August 2016 (UTC)[reply]
OK, I see what you're getting at about the steps, but I was envisioning just a tiny rounding off of the edge, to smooth off the "square" face it typically has. As for the steps, they are already a peculiar size, larger than normal steps. Just try climbing a stopped escalator. It's an effort. ←Baseball BugsWhat's up, Doc?carrots→ 04:16, 11 August 2016 (UTC)[reply]
It's a little peculiar reading some of these responses. No one seems to have directly mentioned the obvious answer. The stairs are the shape that they are so that they fit back together into a flat surface at the top and bottom. I don't see how any "rounded" design could fit that constraint. --Trovatore (talk) 22:37, 10 August 2016 (UTC)[reply]
Nil Einne implied this idea. Rounded edges imply that things are likely to fall in at the top.
If people cared to read those reports about injuries linked above, they would discover that some accidents occur when things are not combed out by the comb at the end of the escalator. A cigarette stub could get caught and ignite all kind of stuff that also got caught there. Hofhof (talk) 01:37, 11 August 2016 (UTC)[reply]
Think StuRat has got it right. Here is a Escalator Step with a sharp edge that affords better non slip grip. In a domestic setting with carpeted stairs, a rounded edge would make since as the carped affords grip (upon a miss footing placement), the step hight is lower and a sharp edge would quickly wear the carpet away on the edges (which is where stair carpets wear the most). Posh homes with un-carpetded stone stair cases have sharp edges. Communal stairs (like in my apparent, local hospital, town hall, etc.), all seem to have sharp edges too. It is the balance of safety and use that denotes the edge of escalators to require a sharp edge. Escalators do indeed have larger than normal steps because the escalator removes the effort (when they are working) of climbing. Hence, they can be shorter and less expensive to install when using high steps. I remember as a child having to trust in the balance of my ear canals to know which way was vertical when descending very steep subway escalators. My visual senses tried to tell me I was leaning the wrong way because the higher step made the escalator appear at lesser angle than ordinary stair and under ground escalators don't afford a horizon line to visually check the vertical. Found the same affect when exploring a beached fishing vessel. Familiarity, told my visual senses that floors were always horizontal and the walls vertical but gravity kept pulling me into the corners. . So and finally, the OP also linked to a litigation layer who can kid people that escalators are more dangerous than static stairs and because they are mechanical, and the owners would rather settle out of court than suffer high litigation cost to show it was really the fault of the litigant’s own clumsiness (lack of every day boring Situation awareness. One can walk through a Nation Park and still sprain and ankle or encounter a copper head etc. It is the balance of risk that is paramount. --Aspro (talk) 10:56, 12 August 2016 (UTC)[reply]
How high are the subway escalators you saw? If they're in a long enough diagonal tube and you look down their axis they can look vertical or horizontal. Especially if you try to imagine it's horizontal or vertical. This must be a byproduct of the visuo-braino system being trained since birth that orthogonal walls are oriented to gravity like you said (cavemen with tent/style architecture wouldn't have this problem) Low tens of feet is high enough to have this effect. Sagittarian Milky Way (talk) 22:39, 12 August 2016 (UTC)[reply]
The Angel station has London’s Underground's longest escalator at 60m/197ft, with a vertical rise of 27.5m. [5] back then (if I remember it rightly) before refurbishment took place. The only vertical clue was the up-lighter pedestals that shone light on to the ceiling. Today the image show load of advertisements on the wall and they may offer the same visuo-braino correction factor. Can't remember if they had the adverts back in those days. Just remember very clearly the sensation that was a bit like vertigo and thrilling to experience. May be the same experience that people get in the Upside down house.--Aspro (talk) 13:18, 13 August 2016 (UTC)[reply]
The risk of impact injuries from falling on an escalator is relatively small. The biggest risk is from getting caught in it and dragged into the machinery. So gaps are a real problem for escalator design. Better a sharp edge with an injury hazard than rounded edges which formed a trap.
One principle used to be that if a gap was small, only a small thing (a piece of fabric) could be caught in it and when trapped, that would tear off - hence the ubiquitous toothed combs where steps re-enter the platform. This principle was recognised to have changed in the 1970s, with the widespread advent of strong synthetic fabrics. A nylon webbing luggage strap (as a likely example) could now be both small, trappable, yet of enough tensile strength to drag the rest of the luggage or garment into the machinery. Andy Dingley (talk) 11:32, 12 August 2016 (UTC)[reply]
Something about the Theory of Global Warming doesn't quite add up
Scientists say that global warming is now irreversiable and the only way for the human species to survive is to colnize other planets. However this always seemed strange to me, since if humans had the knowhow to colnize other planets, all of which are far more inhospitiable than even the worst global warmming senerio, then surely we would have the ability to make earth hospitiable again. Or humans would have to live in space ships, but again surely that same technology could enable humans to live in the sea in big underwater ships? Explain to me how terraforming Mars or living in outaspace is preferable to terraforming Earth or living in the sea, which would surely be easier and cost less money? — Preceding unsigned comment added by 112.213.94.36 (talk) 20:11, 10 August 2016 (UTC)[reply]
Your question is based on a false premise. I don't know of any scientist who says that the only option for human survival is colonization of other planets, and I would be very surprised to hear (a competent) one express such an opinion.
It is generally held that there are irreversible human-driven changes underway (at least, irreversible on human timescales) to our atmosphere and climate, some of which are likely to result in tremendous costs (both social and economic) in the coming decades. None are likely to render Earth's surface completely uninhabitable. If increasing sea levels flood Manhattan (again...), humans will tend to resettle (at great expense) further inland, wherever the new shoreline happens to end up. See, for example, this article for a bit more information. TenOfAllTrades(talk) 20:26, 10 August 2016 (UTC)[reply]
Agreed. Note that the cost is largely dependent on the speed of climate change. If it's slow enough, we can just abandon shoreline buildings when they outlive their usefulness due to age. StuRat (talk) 20:59, 10 August 2016 (UTC)[reply]
The problems facing Venice are mostly caused by land subsidence due to withdrawal of water from aquifers under the city rather than climate change-induced sea level rise. The big increase in frequency of acqua alta events mostly took place between 1950 and 1970. SLR due to climate change does of course reinforce the land subsidence effect. Shock Brigade Harvester Boris (talk) 00:38, 11 August 2016 (UTC)[reply]
Of course there are many many more effects of global warming than having to move human settlements, which you can read all about in said article. The original poster mentions living in the sea. Sounds great, but where you do grow all the food to feed people? Scientists have seriously discussed "terraforming the Earth", also known as climate engineering or geoengineering, though it's generally considered a last resort, as it's something we've never done before. It's probably not a great idea to conduct an experiment on the only habitable planet we have. --71.110.8.102 (talk) 08:31, 11 August 2016 (UTC)[reply]
To those of us paying attention, the OP is more or less correct and notes an interesting paradox. Humanity is currently experiencing what is referred to as the sixth extinction, sometimes known as the Holocene extinction or Anthropocene. Given that 99% of all species that ever existed on planet Earth are already extinct, it is highly unlikely that humanity will survive the next several hundred to several thousand years in its current form based on the known state of the planet which has been rendered all but useless by our greed, delusion, and hatred for non-human life forms, a diverse set of species and niches that we require for survival. The OP accurately notes the technological paradox that many here conveniently ignore due to paradigm blindness. To briefly summarize: since humanity is doomed on Earth for multiple reasons, many beyond our own control and doing, it is recommended that we stop putting all of our eggs in one basket and explore the Solar System and later the nearby star systems to further our survival. However, the very technology required to make space settlement possible is also the same technology needed to fix our problems at home. Many will deny this, few will accept it. — Preceding unsigned comment added by 107.77.227.100 (talk) 04:47, 12 August 2016 (UTC)[reply]
Never have I felt a stronger urge to put {{cn}} templates on a talk page comment.
That 99% of species have disappeared does not validly indicate humans have a 99/100 chance of going extinct; humans are very different from the "average species" if we go by numbers alone (that species must be some kind of insect, it would be more relevant to have extinction stats for mammals for example), and it is the first species whose main risk of extinction is driven by nuclear warfare. I do not see any reason that space exploration research leads to climate engineering advances or vice versa either. And climate change will not drive humanity to extinction - it may decrease population by 90% by violent means of war, water shortages and the like, but we have the transportation technology to relocate at least the wealthiest of us to livable areas.
With the greatest of respect, everything you've written is wrong. Extinction is the outcome for most species; the difference now as to opposed to the deep past, is that humans are driving extinction, which in turn accelerates their own. Nuclear warfare is not and has never been our "main risk" of extinction, and I'm curious where you got that from. Our main risk of extinction is and always has been humanity itself. Your claims are directly refuted and put to rest on the global catastrophic risk page, so there is no need to discuss it. As for the technology paradox that the OP correctly and accurately described, the knowledge needed to build and maintain a sustainable space settlement, either on a planet or an orbiting platform or colony, is the same knowledge and technology needed to repair and sustain our planetary system here at home on Earth. — Preceding unsigned comment added by 107.77.227.199 (talk) 18:44, 12 August 2016 (UTC)[reply]
According to Kaliapparat: "A stylized symbol of a kaliapparat is used in the American Chemical Society logo, originally designed in the early 20th century by Tiffany's Jewelers". There is a source there, that you could follow for a more precise answer.
Do any numbers in between 80 and 85 (or thereabouts) hold any relatively important or relatively obvious meaning in ancient astronomy ? (i.e., other than there being 88 constellations, roughly half of which were unknown to the ancients). — 79.113.220.18 (talk) 04:18, 11 August 2016 (UTC)[reply]
79: the anniversary at which really good oppositions of Mars happen like 2003 AD and 1924 (but not as good as the perfect opposition which happens every x years (x being a specific 3-digit number about a quarter millennium long that I forgot). Maybe. (depends on how accurately they knew these things) Sagittarian Milky Way (talk) 04:45, 11 August 2016 (UTC)[reply]
The comet was observed on several earlier appearances, and Halley is credited with determining that those are appearances of the same object. However, others may well have made that discovery before him. since prior to the scientific awakening, if a royal astronomer made such an observation, the thing to do would be to tell the king, and nobody else, as "knowledge is power". The king could then use a prediction of the appearance of the comet as a means of demonstrating his supernatural powers. StuRat (talk) 16:22, 11 August 2016 (UTC)[reply]
Murphy's Law: You predict a comet 74-79 years afterward, enough years in advance so that the 5 year span is more impressive and Halley and another great comet show up 2-3 months apart and you didn't predict that. (like 1910). The comet comes from the same position each time only in heliocentric coordinates and that was one of Halley's 2 clues that it's all the same comet. An ancient astronomer would have to believe heliocentrism or be some spatial and pattern-finding genius to get that clue (correlating the central point or point of max goodness of a months long comet apparition which is not necessarily at perihelion or Earth closest approach and might be affected by whether it's very foreshortened or placed for maximum angular length to figure out that the comet always comes from the same constellation even though it's too dim to see then). They didn't do statistical frequency analysis of comet years in those days either I don't think. Sagittarian Milky Way (talk) 17:30, 11 August 2016 (UTC)[reply]
The concept the OP is asking about is Numerology, and they read Wikipedia's article on the subject, as well as use it as a search term to narrow it down. Here for example is some sources on the meaning of "80" in various numerological disciplines. Not sure if you'd count them as "reliable", but it may be enough for the OP's purpose. --Jayron3212:23, 11 August 2016 (UTC)[reply]
No. I am talking about an actual astronomical ″thingy″ (cycle or time period, number of stars or constellations, etc.), more or less known to the ancients, and whose numerical value is roughly 82, 83, or 84. — 79.113.220.18 (talk) 12:59, 11 August 2016 (UTC)[reply]
I suppose there might be some culture with 82, 83, or 84 constellations. It might be more likely in the tropics where less sky is forever hidden (or none at all). The most number of stars in the ancient catalog the Almagest in one constellation is 45 and that's a very good catalog. They could see more stars than that obviously but didn't bother cataloging more than I don't know, a thousand or so. By around 1700 they were bothering to go down to enough detail that there's 82+ (100+ in fact) stars in some constellation(s) but that is not Ancient times. This entire catalog can be seen with the naked eye on a moonless night before modern lighting so it's within the technology of the Ancients to make but Flamsteed used a telescope (maybe for more accurate positions?). Sagittarian Milky Way (talk) 16:39, 11 August 2016 (UTC)[reply]
The culture I am investigating has 13 + 21 constellations in the northern and southern hemispheres, much similar to Ptolemy's 15 + 21 constellations. — 79.113.220.18 (talk) 18:37, 11 August 2016 (UTC)[reply]
There was a culture I forgot what it was that liked to have small constellations. They were the kind of people that would call the sickle of Leo one constellation and the lion's butt another (maybe they liked having a name for each day of the Moon's path (27 or 28) and kept that size scale for the rest of the sky) The Ancient Greek culture we get the 48 ancient constellations from (15+21 must be Hipparchos or somebody pre-Ptolemy) is actually a bit more lumper than modern tastes. A few constellations were invented in modern times but were seen by the Greeks (like Leo Minor, Scutum, Lynx). Argo Navis was split into Puppis, Vela, Carina and Pyxis was invented to be Argo's compass. Moderns see a teapot and a teaspoon where Greeks only saw part of the Sagittarius constellation. The Coathanger was not a Greco-Roman constellation even though it's shape is very accurate as these things go, much straighter than Sagittarius' arrow on his bow. But some of these were invented after the 1750s when new constellations usually didn't "stick" anymore or 1930 when the official constellations were set so they'll never be official, only asterisms. Sagittarian Milky Way (talk) 21:12, 11 August 2016 (UTC)[reply]
What is the name of brain-fat and low-priority-energy-usage-fat?
I know that both Brain fat and sometime other fats like Lipomastic fat aren't beta-oxidised easily for energy, either by a natural mechanism (to preserve the brain) or by a metabolic problem (Lipomastia in Men).
Can someone access the following article by S. J. Brodsky and S. D. Drell Physical Review D 22, 2236 (1980) and extract some details about internal structure probing of the electron mentioned in the article? Thanks.--82.137.12.11 (talk) 14:51, 11 August 2016 (UTC)[reply]
How does astrophysics determine the life-cycle of a star?
How can they scientifically conclude that a star will become a pulsar or a black hole? Or a white dwarf? I assume we are observing stars for a minuscule length of their lives. Besides the reasonable assumption that the mass of a star decreases with time, what makes us be so sure that our sun will become a red giant? --Llaanngg (talk) 18:38, 11 August 2016 (UTC)[reply]
A great deal of science relies on indirect observations, indirect does not mean uncertain or imprecise. We've never "seen" hydrogen, gravity, electrons, etc, but we've come up with ways to detect and test them. We might have never "seen" a star turn into a black hole, but we can see a whole bunch of stars, we've "seen" stars in formation and stars in demise, the only "presumption" is that all the other stars are somewhere along that journey, so we model where in that journey each star is and like a jigsaw puzzle, the pieces start making a pattern and falling into place. Sometimes we make a mistake and put a piece in the wrong spot, but eventually if enough of that puzzle is solved, someone will recognize the mistake and set it right. Vespine (talk) 22:33, 11 August 2016 (UTC)[reply]
If you're still looking for an idea, I'd suggest Enterovirus D68, which caused an outbreak of acute flaccid myelitis (problems similar to polio, but with much lower likelihood per infection). There was a large outbreak in the U.S. in 2014. I haven't seen news about it lately ... HOPEFULLY that means it actually didn't have further outbreaks, but there's something extra for you to look up if you want. Wnt (talk) 13:33, 13 August 2016 (UTC)[reply]
Creator Pierre Coffin said, in a 2015 interview, that minions "cannot reproduce or divide themselves..." In other interviews, the creator explains that they have always existed and do not reproduce, because this explanation is less awkward than any alternative.
These statements, which are clearly and indisputably canonical, seem to preclude any classification of minions as any type of bacteria, despite superficial similarities to, say, some kind of lovable giant microbe.
Speaking from personal experience, I have seen a Minion form by inflation, so perhaps these creatures are not as well-understood as we think.
I'm currently dealing with a self-accumulation of a few hundred PET bottles, mostly though not entirely the standard 2-litre version. These have been entirely emptied of their carbonated drink content, the tops firmly screwed back on, and left indoors and out of direct sunlight for anything up to 5 years (all this by myself, so the circumstances are not in doubt). To eliminate one possible idea, they have not at any time been exposed to hot water.
I have noticed that, although firmly sealed, such bottles shrink laterally due to decreased pressure within them, progressively with age. Typically they become concave on three sides, to the extent that they may (in the oldest cases) lose more than half their volume, and the inner curves of the three concave sides almost touch. When re-opened, air is sucked in, demonstrating the reduced pressure within, although those most distorted (and for longest, as the effect is progressive) may not return entirely to their original fully-round profile.
Can anyone reference or suggest the ultimate cause of this? I have already concluded that the caps cannot form any sort of one-way valve and be reacting to temperature changes (which would only be within the range of 9–25 Celcius), and that any drops of the original content that may be left in some of the bottles are too negligable to have any effect. I'm aware that the material is slightly gas permeable, but cannot see why this would operate in an osmotic manner when the atmosphere outside and inside the bottles is essentially the same. I'm also aware that the material is subject to some shrinkage during manufacture (which accounts for most ghits on the topic), and very minor shrinkage thereafter, but this would not account for either the scale of the shrinkage, its confinement to lateral dimensions (the bottles do not get shorter at all), and the reduced internal pressure which seems to be the proximate cause of the shrinkage. {The poster formerly known as 87.81.230.195} 2.123.26.60 (talk) 12:45, 12 August 2016 (UTC)[reply]
My suggestion (original research, though maybe someone can look) is that the plastic itself is starting to break down and softening. shoy (reactions) 15:00, 12 August 2016 (UTC)[reply]
Aside from the loss of internal pressure and apparently consequent shrinkage, the plastic seems unchanged. {The poster formerly known as 87,81.230.195} 2.123.26.60 (talk) 20:51, 12 August 2016 (UTC)[reply]
If the bottles are not homogeneous, such as having a crystal structure or chemical concentration on the inside than on the outside, that could produce deformation such as you suggest. An article about their manufacturing says that impurities form in the PET bottles as they are blow into a mold by hot air and then quickly cooled. There might be differences in impurity concentration or in crystallization between the inside and outside resulting in shrinkage of the outside. Pop bottles are demonstrably not at all gas tight, since this week I threw out two pop bottles which had a 2015 expiration date, and which were flat when opened, due to the carbon dioxide dissolved in the liquid escaping from the bottle. If the outside shrank for some reason more than the inside, it might produce the effect seen, since the air inside would be able to escape over time.Edison (talk) 15:29, 12 August 2016 (UTC)[reply]
I don't see how this would produce a markedly lower pressure inside the shrunken bottles. {The poster formerly known as 87.81.230.195} 2.123.26.60 (talk) 20:51, 12 August 2016 (UTC)[reply]
Likely they're simply leaking more air through the seal and/or plastic itself than "sucking" it back in due to temperature changes.--TMCk (talk) 15:44, 12 August 2016 (UTC)[reply]
Yes, that was my first guess. It seems likely that such a bottle is more resistant to expansion than contraction. A temporary period of low atmospheric pressure would cause the higher pressure in the bottle to force some enclosed air out through the imperfect seal at the cap. Then when the atmospheric pressure increases, the bottle would simple contract rather than have air forced back into it. CodeTalker (talk) 18:15, 12 August 2016 (UTC)[reply]
But once it's shrunken, unsealing a bottle's top results in more air going in, and the bottle re-expanding, so there is no resistance to expansion other than the lower internal pressure. In any case, either the pressure or temperature variations would need to be far higher than are occurring inside a house in a temperate climate (Southern England) to account for such extreme (up to 50%) reductions in volume. Also, the shrunken bottles are never seen to noticeably increase in volume again with temperature or barometric pressure changes. {The poster formerly known as 87,81.230.195} 2.123.26.60 (talk) 20:51, 12 August 2016 (UTC)[reply]
Keep in mind that the positive pressure decreases over time with loss of air volume while the negative pressure will be unaffected.--TMCk (talk) 19:12, 12 August 2016 (UTC)[reply]
As mentioned originally, the bottles are emptied of all but traces of the original carbonated beverage contents (because I drink it all) and then firmly resealed. {The poster formerly known as 87.81.230.195} 2.123.26.60 (talk) 20:51, 12 August 2016 (UTC)[reply]
From US Patent 4260567: It is well known that plastic material has tendency to creep or shrink when heated and this is especially true of oriented plastic containers such as [PET] bottles....Our findings have shown that on the average our bottle has a volume of 1930 cc. and at temperatures of 140° F. (relative humidity 10%) for four hours displays a shrinkage of 65 cc. AllBestFaith (talk) 01:35, 13 August 2016 (UTC)[reply]
First of all, I'm speculating here. I think that the gas inside the bottle, after drinking the carbonated contents, is significantly enriched in CO2. More than 50% CO2 I mean. The plastic of the bottle is slightly permeable to gas, so as long as the partial pressure of the CO2 in the bottle is lower than in the outside atmosphere, the gas will leak out, just as oxygen and nitrogen will leak in. Assuming the plastic is more permeable to CO2 than to oxygen and nitrogen, the pressure in the bottle will drop. It's basically osmosis, but with gas mixtures instead of aqueous solutions. PiusImpavidus (talk) 09:38, 13 August 2016 (UTC)[reply]
Electricity and fish
I'd like to know why if I threw a toaster into the sea, why aren't all the fish in the sea electrocuted, as would happen if I had a toaster in my bath. Is it possible to electrocute hundreds of fish, and just scoop them up when they float to the surface? -- 2A02:C7F:7E06:3000:B4F5:8546:402C:23ED (talk) 16:29, 12 August 2016 (UTC)[reply]
I don't believe a toaster (or hairdrier) thrown on a bath tube will kill everything in it. I expect the fuse to blow if that happen. Of course, in movies it's much cooler seeing someone fry in his bath tube than having a blown fuse. --Hofhof (talk) 21:07, 12 August 2016 (UTC)[reply]
Assuming you mean the fuse has been bypassed, the shock would quickly dissipate as the surface area of an ever-widening hemisphere of water increases. I think it would vary inversely with the square of the distance. So, the shock amount would be 1/100th as great at 10 meters as at 1 meter, or 1/10000th as strong at 100 meters as 1 meter. This means the shock would become nonlethal at a fairly small distance, although it may remain detectable for quite some distance, especially by fish that have electrical sensors (used to detect, prey, etc.).
This assumes the electricity dissipates evenly in all directions. If you had a cathode and an anode, then the field would be stronger between the two than in random directions at the same distance. StuRat (talk) 22:59, 12 August 2016 (UTC)[reply]
I have the unfounded suspicion that most of the bathtub electrocutions occur where someone well grounded in the bath reaches out with a hand, passing the current directly through the heart on its way to the bathtub. I imagine sometimes the offending item is dragged into the bathtub after the shock begins. I would bet that a toaster thrown in a bathtub might not actually kill the person targeted because it would have many paths through tapwater or through less critical parts of the body that would compete against a lethal path - though depending on the circuit breaker used, the total current flow might be very much greater than if you simply stuck a knife into an outlet. The skin resistance of a dry human is actually much higher than that of typical tapwater, especially when impurities have been added, but the internal resistance of human flesh is actually very low, and if thoroughly wet I don't know if that barrier still exists, so this is NOT a guarantee, especially if your water is particularly low in ions. Suffice it to say that without seeing the direct experiment, I think it should not be assumed that what they show in the movies is real. Wnt (talk) 13:49, 13 August 2016 (UTC)[reply]
And now that I've tried my best philosophy, let's see what I can find in data: to start with, there's an interesting phenomenon of a pale stripe on corpses (mostly suicides) at the level of the bathtub [6] which can be postmortem, but might be weaker then. So there's some kind of surface conduction effect I'd never have guessed at which just blows all our inverse-square stuff right out of the water. These guys talking about electrons "making a beeline for the ground" likewise stand exposed. And this article describes a tragic case where TWO girls were killed when a hairdryer fell into a bathtub, which argues very strongly against a "lucky path through the heart" explanation. Lee Harvey Oswald would have been hard pressed to drill through two hearts in a shot. The article also says that fatalities from dropped hairdryers averaged 18 a year. But... the one thing these statistics leave out is how many times somebody did the same unsafe thing and emerged shaken but uninjured, so my skepticism is not totally defeated, but it definitely will maintain a more respectful distance in the future. Wnt (talk) 14:00, 13 August 2016 (UTC)[reply]
Prolonged exposure to an electrical current can kill, even though that current is at a much lower level than would kill instantly. The case of the two girls in the bathtub is an example. For instant death to occur, it would either have to burn tissue or possibly cause the heart to fibrillate, although I suspect that in the later case most people's hearts are able to "reset" on their own (we only hear about fibrillation being a problem in the small portion of cases where this reset doesn't work). However, even at low levels the nerves' actions are interrupted temporarily, and if this "temporary" is long enough to keep the heart from beating until brain death occurs (maybe 10 minutes at normal temps), then death will occur. I myself, as a kid, put my hands on a fence I didn't know was electrified, and my fists compressed around it. Had it not been the type that pulsed on and off, I wouldn't have been able to let go and might have eventually died. (I don't know if my heart was beating during the shock.) StuRat (talk) 15:10, 13 August 2016 (UTC)[reply]
Ocular bruising from tooth extraction
This image, File:Black Eye 01.jpg, depicts "Black eye after extraction of a wisdom tooth". Assuming that the subject wasn't punched in the face during the extraction process, how would the extraction of a wisdom tooth produce a black eye? Even the upper wisdom teeth are much farther from the eyes than they are from other regions, e.g. the nose, and of course they're a decent distance from any spot on the skin; I don't understand how a significant quantity of blood could migrate all the way to the eye-area skin in this manner. Nyttend (talk) 20:19, 12 August 2016 (UTC)[reply]
The upper jaw wisdom teeth are not far from the eye, maybe it's 3-4 cm.
Wisdom tooth extractions is a much bigger damage than a punch. And a punch to the chin could also cause a black eye.
Blood migrates under the skin, under the eye it's visible.
I have seen the same blackness below the eyes after cranial surgery and wondered about the cause. To be punched in the eye at the dentist would be unfortunate. To be punched in both eyes sounds more like carelessness. AllBestFaith (talk) 01:10, 13 August 2016 (UTC)[reply]
The posterior superior alveolar artery and other blood vessels in this diagram connect to both the "tooth area" and the "eye socket area,” and in some cases, can be the source of blood that pools near the eye, causing the cosmetic discoloration
Here is Retrobulbar Hematoma After Third Molar Extraction: Case Report and Review (2010, Journal of Oral and Maxillofacial Surgery). As the title promises, it provides an incredibly detailed case-study and review of this condition (a severe complication of a "black eye" that occurs after a wisdom tooth extraction operation). If you like fancy latin-sounding names for stuff, this is the paper for you... for example periorbital hematoma just means blood pooling in the soft tissues around the eyes, or, "a black eye"; while a "retrobulbar" hematoma is a much more severe case of blood pooling behind the eye). The paper describes the plausible mechanisms that can cause these conditions, and the authors put forward their opinion on the probable cause in one instance: "uncontrolled bleeding from branches of the posterior superior alveolar artery after upper third molar removal may track up through the pterygomaxillary fissure into the pterygopalatine fossa and eventually drain into the retro-orbital space via the inferior orbital fissure."
That's a lot of Latin-esque anatomy terms, but in plain English, this means that blood flowed from the "tooth area" through the "face area" toward the "eye area." In some cases, this is not a problem, and in some cases, it can be a "medical emergency."
The paper I linked above cites some several dozen other papers on the topic, including both periorbital- and retrobulbar- cases ("regular" black eyes and more serious variants), including cases caused by all sorts of other procedures (not just tooth extraction - these conditions can occur in lots of other circumstances!) If you really want to follow up with even more diagrams and medical photographs, that's a starting place. Here's one more: Subconjunctival ecchymosis after extraction of maxillary molar teeth: a case report (Dental Traumatology, 2010), which describes the black eyes without the retroorbital hemmorhage complication.
Chlorpromazine is one of the better-known typical antipsychotics, sold under many names, one of which is Largactil (which redirects to the chlorpromazine article). Promazine is a rather more obscure drug in the same family. As far as I can tell, "Largactyl" is not the name of a drug - the main hits are for an album track by Amebix, and an arts event in Southwark organized by CoolTan Arts (no article, but see Artangel). I suspect that these names are an understandable misspelling of Largactil. However, Largactyl redirects to the promazine article, with no hatnote or mention on the page. Is Largactyl actually a brand of promazine? If so, we should keep the redirect as it is, add a hatnote, and source the name. If, as I suspect, it isn't, we should change the redirect. But I'm not able to determine what the true situation is - I'm sure the Reference Desk is capable of this research. Tevildo (talk) 21:41, 12 August 2016 (UTC)[reply]
Largactil® is a trademark for chlorpromazine hydrochloride first registered in 1953, renewed in 1954 but now expired (according to US Patent Office). This might be confirmed by the Marketing Authorisation Holder for Largactil in the UK which is: Sanofi, One Onslow Street, Guildford, Surrey, GU1 4YS, UK. Tel: 0845 372 7101. I confirm that Largactyl does not show up in a trademark search, only as the name of a heavy metal noise musical composition, and there's nothing to indicate a connection to Promazine. Tevildo is correct. AllBestFaith (talk) 01:02, 13 August 2016 (UTC)[reply]
Thanks for the information! Is Amebix the best target for the redirect? It's the only reference in the encyclopaedia to anything actually called "Largactyl". Or would it be better to redirect to Chlorpromazine as a likely misspelling? Tevildo (talk) 08:49, 13 August 2016 (UTC)[reply]
August 13
Mithril
Is it possible that mithril, as described in Lord of the Rings, is actually titanium or one of its alloys or compounds? For reference purposes, here are the properties of mithril: "It could be beaten like copper, and polished like glass... light and yet harder than tempered steel... its beauty was like to that of common silver, but... did not tarnish or grow dim." Cf. the properties of titanium (from the article): "silver color, low density, and high strength... highly resistant to corrosion... highest strength-to-density ratio of any metallic element... as strong as some steels, but less dense... quite ductile... lustrous... tensile strength of over 1400 MPa... slow to react with air and water at ambient temperatures... excellent resistance to corrosion, almost equivalent to platinum." What do you think about this hypothesis? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 03:02, 13 August 2016 (UTC)[reply]
Maybe we need to pull out a copy of the Silmarillion to be sure of the details, but I recollect that mithril glows blue in the presence of orcs... or at least, can be made to glow blue. To my knowledge, titanium does not exhibit this property.
It is probably best not to over-exert your intellectual efforts trying to bring concordance between Tolkien's fictional writings and actual facts of scientific metallurgy in the real world.
(If any nerd enthusiast comes along to quibble over whether "first age" Elven blades were actually forged from iron rather than steel or mithril... all I can say is, this isn't going to yield a productive engagement on Wikipedia's science reference desk, but a great place to discuss it might be at the Lord of the Rings wiki article talk page).
Titanium (even alloys designed for hardness) is very soft actually. The best way to think of it in relative terms is "better than aluminum." Aluminum is also a ductile, light, and forms a very resistant oxide shell. The main advantage is that it has better strength to weight ratio than steel which makes it ideal for certain narrow applications. Now titanium-nitride is harder than steel, but it's a nonmetallic ceramic (crystal), and so has all the downsides of a ceramic. Honestly the vague description of mithril could be anything from stainless steel to aluminum --Savonneux (talk) 05:56, 13 August 2016 (UTC)[reply]
Nitriding of the surface layer? (Did dwarves have the technology to do that? They might have -- salt nitriding could in principle be done with medieval technology, in fact this could have been one of the steps in producing Damascus steel. As an aside, Damascus steel might in fact have been Tolkien's inspiration for mithril in the first place -- although the physical properties don't entirely match up, because Damascus steel rusts rather rapidly and mithril doesn't!) 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 07:35, 13 August 2016 (UTC)[reply]
In our article on mithril there is a quote that says, "Mithril! All folk desired it. It could be beaten like copper, and polished like glass; and the Dwarves could make of it a metal, [italics added] light and yet harder than tempered steel. Its beauty was like to that of common silver, but the beauty of mithril did not tarnish or grow dim." It is hard to tell for sure but it seems like there is something called mithril, from which it is possible to make something, "light and yet harder than tempered steel" i.e. pure mithril, whatever it is, is soft enough to be beaten like copper. Mind you, pure titanium doesn't seem that soft to me---but perhaps these figures are for the heat treated form. The Encyclopedia of the Chemical Elements by Hampel (1968, p. 735) gives it a Vickers hardness of only 80–100 which is quite low. Sandbh (talk) 07:54, 13 August 2016 (UTC)[reply]
The thing about being "beaten like copper" sounds like it's ductile, and perhaps alloyed to become harder. This actually reminds me more of aluminum, which was indeed in former times quite a rare and precious metal, and actually is used for armor by some reenactors. [7][8] This said, somewhat mysteriously, the descriptions given there make it sound like it is not really very good as armor. I would have thought there'd be a way to alloy it for hardness and strength, and to use appropriate amounts still well lighter than steel, but one issue is that commercial workers have some reason to prefer working with a simpler and more ductile material. I don't know if its potential has really been explored in this context, simply due to historical accident.
But with weapons there's a more fundamental problem, which is how do you do damage to someone with an ultra light sword? But I don't know if Tolkien even wrote about mithril swords. Wnt (talk) 13:18, 13 August 2016 (UTC)[reply]
This is an absurd discussion. Tolkien was not a metallurgist, and he certainly didn't research the material properties of different metals before writing that passage. He just made up those properties. Arguing about whether mithril is "really" titanium is like arguing about what specific trees Huck Finn's raft was made from. If it's not mentioned in the book, there's no answer. CodeTalker (talk) 14:36, 13 August 2016 (UTC)[reply]
Matter at the beginning of the universe
Why people are so confused about the beginning. I think that was a statistical incident. I think that universe came out as matter because it was in a decision making situation between matter and anti-matter (like head and tail). If universe was so dense, it may have been only given one chance - that is its chance of matter/ anti matter creation may be only one. If great crunch theory is correct, then universe may alternate between matter and anti matter, making the whole probability 1 is to 1 if large number of big bangs are counted. Is my thinking correct/ incorrect/ good/ bad?--G.Kiruthikan (talk) 09:34, 13 August 2016 (UTC)[reply]
The main problem with your idea is that there was no one "coin flip". Baryogenesis begins when there is enough energy in the universe to create protons and antiprotons in immense numbers from nothing (but the energy, that is; it's the opposite process of particle and antiparticle colliding to produce energy). So there was, at that point, a quite equal ratio between a huge number of each type everywhere throughout space. And we now can look out 13.7 billion years in any given direction, which means if I understand correctly that we see patches of universe all over the place that had to settle whether to be dominated by protons or antiprotons during a rather short transition of history during which they did not even have time to look at each other via the propagation of light. (Though we can't actually see back to the baryogenesis era itself, we can see patches of universe which, like ours, have been through it) Yet there are no borders where matter and anti-matter collide anywhere we look. So that means it's not a statistical effect, but something which occurred pretty much uniformly, everywhere in space, all at the same time as the matter cooled to the point where there weren't any extra antiprotons available from spontaneous pair creation. This implies an asymmetric physical law. Wnt (talk) 13:24, 13 August 2016 (UTC)[reply]
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