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: Thanks ]. Has it been used in a health care context? ] (]) 18:40, 4 June 2014 (UTC)
: Thanks ]. Has it been used in a health care context? ] (]) 18:40, 4 June 2014 (UTC)
::You mean like using ] as a treatment for cancer? ←] <sup>'']''</sup> ]→ 19:07, 4 June 2014 (UTC)
::You mean like using ] as a treatment for cancer? ←] <sup>'']''</sup> ]→ 19:07, 4 June 2014 (UTC)
::: This doesn't strictly apply to health care, since in biology alternative theory properly exists only as an afterthought to alternative practice. If you find that a root helps an ailment, you don't really need an explanation for it, only data.
::: Several examples can be found that originated from the Soviet Union around the 1940s: ], an effective method of dealing with antibiotic resistant bacteria; low dose application of ] for flu and other infections diseases; and some practices based on the ideas of ], most notably ]ization. I would suggest that in some of these areas the U.S. and other Western culture not merely ''hasn't'' caught up to Soviet practice that has been ongoing for much of a century, but quite possibly may ''never'' catch up, either in theory or in practice, because there is some aspect or other about them that is incompatible with the present bureaucratic order. On Misplaced Pages, we cover the first of these pretty well, the second not at all, and the third is represented to be solely a form of chimerism which is theoretically more palatable but discards other literature.<ref></ref><ref></ref><ref></ref> ] (]) 22:11, 7 June 2014 (UTC)
== Distant times are closer than more recent times? ==
== Distant times are closer than more recent times? ==
Revision as of 22:11, 7 June 2014
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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.
What is meant by by dark reddish complexion? How does it look like? Which people other than Red Indians can be said to have dark reddish complexion. — Preceding unsigned comment added by 117.194.228.68 (talk) 02:54, 3 June 2014 (UTC)
But they aren't Caucasians. Well, I suppose a few of them are, but not many.
Sorry, the term just bugs me. It's one of those attempts to sound more precise, that just winds up being inaccurate.
You can say Caucasoid, if you know what it means, and that's really your intent — a category from a somewhat dated, but possibly not entirely obsoleted, system of racial classification. But not "Caucasian". A Caucasian comes from the Caucasus.
For StuRat's original comment, the best term is probably "light-skinned" (the lightest-skinned "blacks" may be lighter than the darkest "whites", and would equally be covered by the comment).
But you know, if what you really mean is "what the man in the street would call white", then just say "white". No need to look for a scientific name for a less-than-scientific (but still widely understood) concept. Just say what you mean. Anything else just feeds the euphemism treadmill, and that's not a good thing. --Trovatore (talk) 08:44, 4 June 2014 (UTC)
They can temporarily, as I said. Look at the pic at the top of the sunburn article to see what I mean. The skin of Caucasians is somewhat translucent, so you can see the blood beneath it, to some extent. While healing from a sunburn, more blood is pumped closer to the surface, and this explains the dark red color. StuRat (talk) 13:52, 3 June 2014 (UTC)
No, because science has provided us with no evidence that aliens exist. This question does not belong on the Science Ref Desk. HiLo48 (talk) 08:33, 3 June 2014 (UTC)
I find the idea that first-century Palestine was infiltrated by a space-alien who just happened to look exactly like a 30-year-old itinerant rabbi to be a lot less plausible than that an actual rabbi did some unusual things that his audience later reported in their own terms as miracles. AlexTiefling (talk) 08:42, 3 June 2014 (UTC)
I don't have an answer to the question - but wanted to ask for a clarification: are you asking "Could Jesus have been a space alien" or are you asking "Do we have the technology to perform the equivalent of biblical miracles"? The latter seems a fairly reasonable question for this desk.Phoenixia1177 (talk) 08:45, 3 June 2014 (UTC)
From a similar perspective, The Sins of Jesus (a novel), attempts to imagine the story of Jesus as a teacher who used sleight-of-hand and similar tricks that would have been available to magicians of his day in order to capture the attention of the audiences he lectured to. Dragons flight (talk) 10:18, 3 June 2014 (UTC)
The trouble is that we don't have accurate reports of these "miracles". If you take something like the loaves and fishes story - a tiny amount of food somehow feeds a large crowd of people, and after everyone has eaten, there is considerably more food wasted than there was food to start with. On the face of it, that would be a clear violation of conservation of mass laws - so it's certainly not possible within the realms of known science - and because conservation laws seems to be rather fundamental to our universe, it doesn't seem likely that even a very advanced alien species could pull this one off as it is described in the Bible. So if this event happened at all, there must be some kind of a failure of description of what really happened. A much simpler, and far more likely, explanation is something similar to what happened was in an impromptu block-party we once had when we'd invited some friends over and we had made some snacks for us to share - but some of our neighbors heard the party and came over to join in - and pretty soon we were running out of food. So the neighbors popped back home and emptied their fridge of snack food and brought it along - cold pizza, a few beers, some bags of potato chips...and along the way they roped in some other people who lived in the same apartment block. By the end of the day, the party had spread out into a second apartment, about a hundred people were partying and everyone was bringing food and drink...and there is no question that by the time we came to clean up, the amount of party left-overs was far more than we'd started off with. The snowball effect of excited people bringing small amounts of food and drink and sharing it widely produced an event that nobody who went to it will ever forget. The way it brought the community together was quite stunning - and it had long-term repercussions in how everyone who lived there got along. This had the feel of something "miraculous" and seems to have the exact flavor that the descriptions of the "feeding of the 5,000" event seem to be trying to impart.
You could say that the party was fed by the tiny amount of food we kicked it off with...and that seems overwhelmingly likely to be what happened in the loaves and fishes story - there is some kind of a political/religious rally - everyone is kinda peckish - somebody donates a small amount of food, but it's clearly not enough - so people disappear for a while and come back with more food...this seems a little 'miraculous' and after the story has been re-told, written down, translated, interpreted, re-translated - and who-knows-what else...it becomes a magic trick.
So before you look for aliens and advanced science, it's better to look at more mundane explanations because the simpler the explanation, the more likely it is to be correct. SteveBaker (talk) 12:59, 3 June 2014 (UTC)
People seem to have been far more naive then, due to a lack of training in critical thinking, skepticism, and science. Whereas now we can check on any magician's trick by asking how it's done on the Internet (several such Q's have been posted here), back then they had no way to check on something.
So Jesus could have had a table with a hole cut in in, and somebody underneath reaching up through the hole to replace the food whenever it ran low and the cover was put back on, then plugging the hole back up again. Note that such tricks were common at the time from religious leaders. Much as absurd costumes go with Mexican wrestling now, back then any religious leader was expected to "perform miracles". Now, all this doesn't mean that Jesus was a total fraud, he may have just wanted to "save" as many people as possible that day and considered a little trickery acceptable in working towards that goal. StuRat (talk) 13:50, 3 June 2014 (UTC)
The explanation for that story is that Jesus opened His satchel and shared His food, which encouraged everyone else in the crowd to do likewise, to the point where there was food left over which could be donated to others. It's a good metaphor for what Christian love is supposed to be able to accomplish. In modern terms, it would be called "pay it forward". ←Baseball Bugscarrots→ 15:44, 3 June 2014 (UTC)
I want to add upon Steve Baker's answer (Which I liked very much!): I don't think that even the first interpretation must contradict the Conservation of mass Law, because, I think, you could philosophize and say that the particles that have made the "Miraculously appearing new food" where brought by god into this time and place, directly from another dimension of the existing physical universe; If one seems fit to believe such an interpretation - Go ahead. Ben-Natan (talk) 04:42, 4 June 2014 (UTC)
If there is a God, conservation of mass is something it, assumedly, could circumvent (thus, not absolute); if there is no God, then it conforms to known science. My point being: if you can assume God, you don't need to assume physics gets in its way - at least, on traditional accounts - thus, you don't, then, need to provide an explanation for how God managed it.Phoenixia1177 (talk) 06:53, 4 June 2014 (UTC)
Indeed - if "God did it" is the explanation, then since he's supposed to be both omnipotent and omniscient, he could have either just magic'ed the food into existence - or rerouted the wiring of everyone's brains an hour after there wasn't enough food to implant the memory that they'd eaten well. If you can do absolutely anything, without recourse to the limitations of the laws of physics - then there is probably an infinite number of ways to pull off this trick. If God is limited by the laws of physics - then whatever he does can be done by a sufficiently advanced alien civilization. Right now, finding a way to pull mass from a parallel universe is rather more unlikely than finding a way to violate the conservation laws...so I'm not sure that this suggestion adds any explanatory power. SteveBaker (talk) 13:49, 5 June 2014 (UTC)
What brings mercury into the fish in the first place, and when they're caught, why can't there be any sort of method to remove mercury from these fish?
We could stop polluting the sea with mercury. That would eventually get rid of practically all of the problem. Mercury in fish discusses the whole business. Dmcq (talk) 09:07, 3 June 2014 (UTC)
Since it's in the muscle I assume you would have to pulp the fish to be able to extract the mercury, which wouldn't be economical.--Shantavira|11:50, 3 June 2014 (UTC)
An approach to lead poisoning that was known to Aulus Cornelius Celsus was to use "walnut juice"; the insoluble fraction of walnuts tends to soak up lead (, though this isn't the source I was looking for). If our medicine could catch up with the ancient Romans, well-chosen sources of natural fiber could be taken as routine supplements with meals to absorb some of the heavy metals. The fiber, more than harmless, would simply be excreted. Wnt (talk) 17:41, 3 June 2014 (UTC)
The mercury is obviously not found in a concentrated chunk in the fish, it is spread throughout the tissues, and a s mentioned above, addressing that would require pulping and huge expense. The standard treatment for mercury poisoning is chelation therapy, you might read there. μηδείς (talk) 18:09, 3 June 2014 (UTC)
Human genetics
My understanding is that there are certain genes where every human shares the same allele, and other genes where there are many alleles in the human genome. What percentage of genes fall into the first category? 38.108.87.20 (talk) 12:57, 3 June 2014 (UTC)
I know that you can find out whether there are no known SNPs associated with a gene by . That site has a good set of APIs, so you could program a script to run through and count up how many still have no SNPs associated, but it would be a significant amount of work. I bet someone has done it though, if you can just think of the right way to search... Wnt (talk) 17:27, 3 June 2014 (UTC)
Just to clarify: my understanding is that the lack of known SNP is a very poor proxy for "every human shares this allele" - right? I mean, the human genome project only had 5 individuals in the private portion and 40 (?) in the public portion. So it stands to reason there are many unknown alleles out there, especially for non-famous loci... Also, turning the question around: are you aware of any specific loci in the human genome which have been thoroughly sampled, and found that there is no variation in allele? Is there a specific name for such a thing that I could use for searching? SemanticMantis (talk) 19:43, 3 June 2014 (UTC)
The HapMap data is also at NCBI, so as far as I know it should be up-to-date for those individuals also when searching Gene, but I will admit I haven't gone hunting for SNPs in a gene lately to be sure. Wnt (talk) 02:09, 4 June 2014 (UTC)
I don't know whether the current database rules this out, but in a probabilistic sense it is impossible for it to be true. Because of the way the genetic code works, a substantial fraction of single-nucleotide mutations are "neutral", meaning that they have essentially no functional effect. The probability of any gene having nobody in the world with even a single neutral mutation is vanishingly small. Looie496 (talk) 15:16, 4 June 2014 (UTC)
Thanks, @Looie496: and @Wnt: - that's what I thought too, but I wasn't really confident. I appreciate the probabilistic reasoning, and agree with it. However, I'm not sure how rule out something like this: there might be some very primitiveallele and locus that admits noneutral variation. Something that incorporates none of the normal redundancies or error correction. It seems possible that, if the allele is exactly "right" then e.g. some structural protein is correctly produced. But if there are any changes to that allele, it becomes lethal to a developing fetus. That's a very strained and slightly ignorant example, but it's the only way I can think of that a locus would have no variation across the extant human population. (overlinking for benefit of the group, thanks to Andrew for the reminder :)SemanticMantis (talk) 16:00, 4 June 2014 (UTC)
Well, now we're getting into a tricky area concerning what the word "gene" means. Most of the time nowadays when a scientist uses the word "gene", the intended meaning is the portion of a chromosome that encodes a single protein or some other product such as an RNA. That's the meaning I had in mind when I answered the question. A gene, in that sense, is generally a few hundred nucleotides in length. But there are other possible ways of using the word, which may yield a different answer. Rather than write out a long explanation, let me point to a blog post I wrote recently about this problem, "There is no such thing as a gene". Looie496 (talk) 18:05, 4 June 2014 (UTC)
Thanks, User:Looie496, for linking to that post, although seeing "Die Selfish Gene" made me fear it was in Tscherman. The only flaw is that your treatment wasn't booklength. Non-biologists (and too many supposed Biologists) are absolutely convinced Dawkins is the shit and his concept is both meaningful and irrefutable. I prefer SJG'sand especially Ernst Mayr's telling criticisms. μηδείς (talk) 18:26, 4 June 2014 (UTC)
Right, that's why I was careful to talk in terms of loci and alleles. I don't think we really need the word "gene" much anymore. I read your blog post, and found it interesting, but I don't see what it has to do with my hypothetical allele that must be identical across all viable individuals. I guess you mean the bit about recombination? In my hypothetical example, recombination would still preserved the allele, because there is only one version of it that "works" -- But, until I hear otherwise, I'll assume that the correct answer is that there are no loci for which there is no variation in alleles across the human species. SemanticMantis (talk) 19:00, 4 June 2014 (UTC)
What about the genes for having mass, or winglessness? I think we all share identical versions of those. μηδείς (talk) 02:09, 5 June 2014 (UTC)
I subscribe for Astronomy magazine. In July 2014 issue on page 34 there is a picture of three types of black holes. The type 2 in the middle does not rotate but the accretion disk (AD) rotates. The picture shows a counterclockwise AD rotation which is of course irrelevant. In the picture above it (picture #1) the black hole has a spin, it rotates clockwise but the AD rotates in the opposite direction. The lowest picture (#3) shows the black hole rotating counterclockwise and the AD likewise rotating counterclockwise. They both spin in the same direction.
My questions are:
(1)How come we have a no-spin black hole if as many times has been stated in this website, everything in the universe has angular momentum. More than that, since the AD for this black hole rotates (counterclockwise), it has a mass and angular velocity, therefore it has angular momentum. When this mass ends up in the black hole it MUST transfer the angular momentum to it. Where has it gone?
(2) When the AD and black hole have opposite spins then the mass falling into the black hole should subtract the existing angular momentum of the black hole and eventually stop it. Then at the next stage the black hole should begin rotating in the direction of the accretion disk (synergistically). Is it correct?
(3) When we have AD and the black hole spinning in the same direction and the accretion process keeps feeding the black hole continuously the transfer of angular momentum should continue indefinitely and the black hole should accelerate? Is it correct? This may not be true though. The momentum increase may occur because of the increase in the mass of the black hole and not because of the speed.
If you are asking whether alternative scientific theories have been described in Misplaced Pages, yes of course. For example Black hole#Alternatives. If you are asking something else, please explain. Please do not ask the same question on alternative desks.--Shantavira|07:49, 4 June 2014 (UTC)
What that principle is saying, is that if an idea or approach has significant support among mainstream scientists, even if they are a minority, then a Misplaced Pages article should not state that the idea or approach is pseudoscience. Since this is a negative principle -- defined by what an article does not say -- it's hard to point to specific examples in a useful way. One article that I think is an example, though, is cold fusion -- it is not described as pseudoscience in the article even though the majority of scientists think it is bogus. Looie496 (talk) 14:49, 4 June 2014 (UTC)
This doesn't strictly apply to health care, since in biology alternative theory properly exists only as an afterthought to alternative practice. If you find that a root helps an ailment, you don't really need an explanation for it, only data.
Several examples can be found that originated from the Soviet Union around the 1940s: phage therapy, an effective method of dealing with antibiotic resistant bacteria; low dose application of interferon alpha for flu and other infections diseases; and some practices based on the ideas of Michurinism, most notably graft hybridization. I would suggest that in some of these areas the U.S. and other Western culture not merely hasn't caught up to Soviet practice that has been ongoing for much of a century, but quite possibly may never catch up, either in theory or in practice, because there is some aspect or other about them that is incompatible with the present bureaucratic order. On Misplaced Pages, we cover the first of these pretty well, the second not at all, and the third is represented to be solely a form of chimerism which is theoretically more palatable but discards other literature. Wnt (talk) 22:11, 7 June 2014 (UTC)
Distant times are closer than more recent times?
Hi - a physicist was talking on the radio about a year ago about how, in terms of time travel, were it possible, it would require less energy to travel into the distant past than the recent past. His explanation was counterintuitive but elegant and simple but my recollection of it is very dodgy. Maybe I should wait until it's in the distant past before I try to recover it...
Can anyone help with an explanation of this principle?
I've never heard anyone say that, it appears to make no sense, and I couldn't find anything relevant in a web search. This may be a permanent mystery unless you can remember enough to track down the radio show. Speculating wildly, it could have been about the idea that looking at distant objects is "looking back in time", and the fact that it's easier to see quasars or the cosmic microwave background than some more recent but less energetic events... -- BenRG (talk) 16:02, 4 June 2014 (UTC)
String Theory and the various interpretations of quantum mechanics
What is the relationship between String Theory and the various interpretations of quantum mechanics? ST seems also pretty interpretative to me, and covers QM too, so is it compatible with all? From what I understood, ST combines QM and General Relativity into one single mathematical model. To me, this seems to imply that you're looking for an underlying framework that explains both models... Doesn't that require "hidden variables"? Thanks very much for any clarifications you can provide. --Jules.LT (talk) 03:01, 4 June 2014 (UTC)
As far as I can tell, string theory gives no insight into the basic rules of quantum mechanics. It just assumes them. It is probably incompatible with some interpretations (e.g. Bohmian mechanics) because they require point particles or a fixed spacetime background or something of that sort. -- BenRG (talk) 07:10, 4 June 2014 (UTC)
Naively, I thought that ST assumed a more fundamental (or at least more abstract) set of properties of these putative strings, and then derived rules of QM (among other things) as a consequence of these more basic assumptions about strings. Is that a fair understanding for an educated non-physicist? It does mesh well with the notion that ST is very difficult to empirically test directly, and that it might just all be "made up". SemanticMantis (talk) 15:50, 4 June 2014 (UTC)
No, no one has ever found a more basic principle underlying quantum mechanics, i.e., the wave-like interference between different quasi-classical histories of a system that leads to quantized energy levels and entanglement. String theory's quasi-classical part has a lot of unusual features, but the quantum part is the same as ever (as far as I can tell).
Quantum gravity is hard to test simply because gravity is so weak. Any approach to quantum gravity has that problem. -- BenRG (talk) 01:59, 5 June 2014 (UTC)
Likewise, this is my understanding. Generally, the various interpretations do not change the mathematics; they are about the phenomenon of wavefunction collapse, which has nothing to do with mathematics, as far as anyone knows. The GRW theory does change the maths, but this is highly speculative at this stage. So if string theory became the dominant theory, interpretations of quantum mechanics would become effectively interpretations of string theory as well, although you would not expect anyone to adopt this terminology. IBE (talk) 11:41, 4 June 2014 (UTC)
Thanks. For Reference, I posted the question in a sciency forum where I'm starting to get interesting answers too --Jules.LT (talk) 13:23, 5 June 2014 (UTC)
1) The mortality rate will depend on many different factors like the maternal age, maternal health, abortion method and competency of the person performing it, access to after care etc. These will vary quite significantly from country to country.
2) Many countries severely limit 'late term abortions' or even all abortions. Many such abortions will therefore be carried out illegally. Obtaining reliable statistics for such abortions is rather difficult, even more so if the government makes it difficult. Further the number of such abortions will likely vary significantly depending on a host of local factors.
3) Note that this also means that many reported abortions will probably be in the lower end of the fetus age if we're talking about a wide range (e.g. second trimester). On the converse side, it will often be the case that you're more likely to have reports of problematic abortions at a later fetal age and that many reported abortions (i.e. legal ones) will be in problematic pregnancies anyway. Although back on the earlier side, some reported abortions may be less problematic pregnancies where the mother or her family is sufficiently wealthy that they can obtain a more above board abortion and associated competency and after care, even in cases where it's questionable if they qualify under law. However whether these are reported will again depend significantly on a whole host of local factors. (And back to the converse side, depending on local factors it's possible even if the abortion is legal, a wealthy mother may be more likely to have it unreported.)
4) You didn't define late-term abortion, as our article says there's no universal definition.
Therefore there's no way anyone can hope to come up with an 'exact' figure, even if by that you mean an average figure for all abortions performed throughout the world in one defined year (or whatever time period) according to some defined meaning of late term abortion (e.g. anything over 20 years).
But to give one figure, says ~10 times 0.8-1.5 per 100000 abortions is the maternal mortality rate for second trimester mifepristone–misoprostol in the US. I'm not sure the source itself is reliable, but hopefully their source is. Of course bearing in mind what I said earlier, many of these second trimester abortions may not fit in to whatever definition of 'later term abortions' you're using.
It depends on the definition of "abortion". As I understand it, an abortion is the intentional termination of a pregnancy; the death of the aborted fetus is a usual but not necessary consequence. "Pro-life" murderers are another matter still... --Roentgenium111 (talk) 16:03, 6 June 2014 (UTC)
This is going to be extremely tough to answer with any reliability. The problem is, in many places by law, and in most others by custom, a late term abortion is only going to be given to a mother whose life is already in danger. As we usually think of defining it, the risk of the abortion would need to exclude, say, the risk of death from eclampsia, even though the abortion may be given due to eclampsia being underway. In addition to potential arguments over the cause of death (and the philosophy of cause of death in general) blurring the statistics, there's going to be a lack of controlled experiments, because there won't be many situations in which a doctor is willing to randomly abort or not abort any given fetus to get data. Wnt (talk) 12:07, 4 June 2014 (UTC)
Yes, Compte Diable. But that's like saying human life expectancy will be drastically shortened if the sun mysteriously goes supernova. μηδείς (talk) 18:16, 4 June 2014 (UTC)
No, because a person's life span is negligible when compared with the time until the Sun will go supernova (which is never, although it will eventually go nova), while the life span of a (non-microscopic) black hole may be significant compared with the life span of the universe, depending on which end-of-the-universe theory you subscribe to.
A better analogy for the lifespan of a black hole might be the lifespan of trees, which could be significantly affected by forest-wide events, such as forest fires. StuRat (talk) 18:41, 4 June 2014 (UTC)
Pay better attention StuRat, I said if it were to mysteriously go supernova (i.e., now) not eventually go nova. μηδείς (talk) 17:17, 5 June 2014 (UTC)
Again, not a good analogy, because you are comparing something no scientists expect to happen (the Sun going supernova for no apparent reason) with something many do expect to happen (the end of the universe). StuRat (talk) 12:44, 7 June 2014 (UTC)
And of course, death by Hawking radiation is as yet entirely theoretical; although we're now pretty sure the black holes exist (see Sagittarius A* for one particularly good candidate), the precise details of their physics have not been observed, but only inferred or extrapolated from physical laws based on observations of other things. -- The Anome (talk) 17:24, 5 June 2014 (UTC)
I don't understand how alternating current works without turning off and on and off and on whatever it is powering. Direct current makes sense, but alternating current doesn't. How doesn't it make the lights flicker constantly? — Preceding unsigned comment added by 190.74.66.93 (talk) 23:02, 4 June 2014 (UTC)
In an incandescent bulb the light is generated when the filament heats up because of (essentially) friction between moving electrons and the wire (this is called electrical resistance, but the process is not different enough from rubbing your hands together really fast to make much of a difference). Here's the deal: if you rub your hands really fast in one direction along, say, the carpet, they get hot. This is akin to direct current. If instead, you rub your hands back and forth rapidly across the carpet, they also get hot. This is akin to alternating current. The filament of the light bulb heats up regardless of which direction the electrons are moving, so the light bulb filament gets hot enough to glow regardless of whether the electrons are moving left, right, or both ways in rapid succession. --Jayron3223:55, 4 June 2014 (UTC)
How do the electrons travel along the wire from the power station to the light bulb if they are always changing direction? Like a person taking one step forward and one step back, they wouldn't get anywhere. — Preceding unsigned comment added by 190.74.66.93 (talk) 23:59, 4 June 2014 (UTC)
Well, yes and no. A electrical signal travels at approximately ⅔ c. That's about 200,000 km/sec, or a wavelength of 4,000km for a 50Hz source. However, with the hydraulic analogy, imagine a double-ended piston as the source, it is connected via long pipe to a paddle wheel. As the piston is pulled in and out, the wheel will turn, even though no water from the piston reached the wheel. CS Miller (talk) 10:08, 5 June 2014 (UTC)
That's the speed the energy travels at. The wavelength of such a wave is not the distance any putative individual electrons would travel (once you get into the model, the concept of the "individual electron" becomes problematic, but at this level of thinking, we can just go with it). Consider the picture someone posted above. The individual dots are moving much shorter distances than the wavelength. Each dot only moves about 1/20th of a wavelength. You're confusing amplitude (the distance moved by a single element within the medium) versus the wavelength (the distance between successive wave pulses). --Jayron3213:10, 6 June 2014 (UTC)
Indeed. Going back to a hydraulic analogy (with the usual warning about not-quite-perfect analogies), consider a syringe full of water. As you press on the plunger at one end, even if you press veeeeeeery slowly, water comes out the other end almost immediately. (Actually, for a regular human eye, you won't be able to see the time between pressing the plunger and water starting to move at the other end.) The speed that individual volumes of water move down the syringe has essentially nothing to do with how fast information about a change in pressure travels down the syringe. A drop of water next to the plunger's head may be pushed along at a leisurely few millimeters per second, but the effects of the moving plunger propagate down the syringe at about the speed of sound (in water)—about 1.5 kilometers per second.
Similarly, applying an electric field to electrons at one end of a wire only moves the electrons themselves very slowly; in a copper wire, the so-called drift velocity of the electrons is on the order of a millimeter per second. (Snails typically travel faster than electrons in a wire.) But the electric field through which those electrons 'communicate' with each other moves information down the wire a lot faster: some significant fraction of the speed of light. If I poke the electrons on one of the wire, the electrons on the other end 'know' about it virtually instantaneously, even though all the electrons in the wire barely moved. TenOfAllTrades(talk) 13:37, 6 June 2014 (UTC)
As a variation of Jayron's carpet-rubbing analogy, imagine sawing through a log with a very long saw. When you push or pull your end the other end moves similarly, not because your end has traveled over there but because the saw is solid and resists attempts to change its length. Electrons in a wire are a fluid rather than a solid, but the principle is the same: they have a preferred density (the density that leaves the wire electrically neutral), so if you forcibly move electrons in one part of the wire, the electrons elsewhere move by a similar amount to preserve that density. -- BenRG (talk) 00:25, 5 June 2014 (UTC)
Electrons in a wire that is conducting alternating current indeed arrive nowhere and merely alternate forwards and backwards, see the image. Because electrons repel one another, the alternating movement is conveyed all the way from the power station to the light bulb. In the bulb filament material, electrons and nucleii are bound together more strongly than in the external cable, i.e. it has significant electrical resistance. As a result, the electron displacements jostle the filament atoms and heat them. With a mains supply frequency of 60 Hz (USA) or 50 Hz (Europe) an incandescent lamp flickers at 120 or 100 Hz respectively since both cycles deliver energy; such high flicker frequencies are imperceptible. However you may just notice the 60 or 50 Hz flicker in a failing fluorescent light tube if only one electrode is emitting. 84.209.89.214 (talk) 00:48, 5 June 2014 (UTC)
Related to above discussion, one can see the on and off fluctuation of a normal fluorescent lamp as follows. Equipment needed: a fluorescent lamp, a light coloured (preferably white) stick a couple of feet long (a white ruler for instance or a short white curtain rod), and a dark background (eg, a dark wall or a blackboard). Stand so that the light is hitting the stick and so you are looking at the stick against the dark background. Then wave the stick rapidly from side to side, observing the light reflecting from the stick. If I have explained this correctly, you will see alternate light and dark bands, light from those times when the electrons are moving rapidly in the fluorescent tube and dark from the times when they are not moving or moving only slowly.
If you do the same experiment with an incandescent lamp, you will not see the bands since the lamp filament is hot and has a "steady" glow. CBHA (talk) 01:43, 5 June 2014 (UTC)
Incandescent filaments don't emit light because there's a current flowing through them; they emit light because they're hot. Due to the thermal capacitance of the filament, it takes a couple hundred milliseconds for an incandescent bulb to turn on or off, which is a lot longer than the four or five millisecond period between maximum current and no current or vice versa of 50 or 60 Hz mains electricity. So even if your eyes could respond that quickly, there really isn't a whole lot of variation in how much light is emitted from the filament over the course of a cycle, anyway. Red Act (talk) 02:47, 5 June 2014 (UTC)
Note that the animation provided above shows a transmission line several wavelengths long. --ToE15:22, 6 June 2014 (UTC)
Testing of prescription drugs for animals
When new prescription drugs are developed, there is a lengthy process involved. In a nutshell, drugs are tested on animals – and eventually on humans – before the drug is allowed on the market for general consumption. And this is all overseen by the FDA. My question is: what is the process for drugs that are prescribed to animals? Do they have some process? Do they do some kind of testing on other animals first? Is this overseen by the FDA? So, what is the analogous process for animal prescription drugs? Thanks. Joseph A. Spadaro (talk) 04:04, 5 June 2014 (UTC)
Note that in many cases animals are given the same meds as humans, such as antibiotics. In that case, presumably once they are proven safe for humans, they are assumed to be safe for animals, too, although this isn't necessarily always the case. StuRat (talk) 04:16, 5 June 2014 (UTC)
You misspelled that word. The correct spelling is "overseen" (note the quote marks). And you need to wiggle your fingers when you say it out loud as well. --Jayron3204:26, 5 June 2014 (UTC)
For the UK, I found this document from the Goverment department DEFRA, which gives guidance on the testing of veterinary drugs. For farm animals I would guess that there's some requirement to test that drugs used on them do not have dangerous effects for consumers on their meat or milk. See antibiotic use in livestock, for example. AndrewWTaylor (talk) 09:17, 5 June 2014 (UTC)
In some cases, it's just a matter of availability. When our vet prescribed some pain killers for our dog, on a long-term basis, I looked up what they were (Yeah! Misplaced Pages!) so I could try to find a cheaper source for them. I discovered that these were drugs that had been designed for human use but had fallen out of favor with physicians for whatever reason. Because dogs can't tolerate many of the modern painkillers that humans use, they are basically stuck using an obsolete drug. Fortunately, they are still manufactured for human use in parts of the world like Russia, and various African countries - and that's the source of the drug for pets. It's hard to ask an animal whether the medication is alleviating pain or not - so knowing that it works in humans means that they probably only had to test for toxicity in each animal species they use it for. This is an interesting role-reversal, where human testing preceded widespread animal use! SteveBaker (talk) 13:40, 5 June 2014 (UTC)
Yes and no. Animals often "suck it up" and keep the pain to themselves. Probably part of their survival technique. For example, in 1973, Secretariat (horse) had an abscess in his mouth and was off his feed, costing him in the Wood Memorial. Someone finally opened his mouth, checked it out, and treated it, just in time to recover and run for the Triple Crown. The horse had not given any direct indication he was in pain. He was just living with it. ←Baseball Bugscarrots→ 20:11, 6 June 2014 (UTC)
To quote a source of which I am skeptical: "Human CO2 contributions will decrease ocean pH by 0.3 over the next 100 years while sections of the world's oceans change by nearly 5 times that amount in a given year."
Does ocean pH change considerably from year to year? Is there evidence that the year to year fluctuation in ocean pH is much greater than the projected decrease of 0.3 pH units in 100 years. Thanks, CBHA (talk) 04:12, 5 June 2014 (UTC)
(edit conflict) It should be noted (and may even be misunderstood by your source!) that pH is a magnitude scale; that is it is a logarithmic (rather than arithmetic) scale. In simpler terms, it is a scale based on multiplication rather than addition; a pH difference of 1 unit represents a difference in acid concentration of 10 times; a pH difference of 2 units represents a difference in acid concentration of 10x10 or 100 times; pH difference of 3 is 1000 times different, and so on. A pH decrease of 0.3 represents a doubling of acid concentrations in the ocean, while 5 times that (5x2 = 10) would be a pH difference of 1.0. So, what the quote seems to be saying (assuming the writer actually understands the math involved) is that human CO2 generation stands to double the amount of acid in the oceans; while natural variation can lead to pH swings of 1 pH unit (10 times acid concentration). I find neither claim to be fantastical (but that doesn't make either claim true). Furthermore, logic dictates that even if both claims are true, that doesn't necessarily lead one to any particular conclusion regarding the importance of human-generated CO2 to ocean chemistry... --Jayron3204:23, 5 June 2014 (UTC)
It might be useful if you could indicate the exact source, so we could put the statement into context. (I can't find that exact quote through a Google search.) Guessing cynically, I would ask if it's from a climate change denialist of some sort, who is trying a bit of verbal sleight of hand to argue that the anthropogenic (human-caused) changes are smaller than the natural ones, so we don't need to worry about polluting the environment. (Did I guess right?)
There are a couple of problems there. The obviously slippery bit is the part that says "sections of the world's oceans". "Sections"? How big? Which ones? What fraction of the entire ocean's area or volume? (If I stood on the seashore and squeezed a lemon into a bit of calm water, it would be technically accurate to say that I changed the pH of a "section" of the world's oceans by several units.) Yes, there are significant variations in pH of surface and coastal waters in some areas, largely due to seasonal effects (spring snowmelt washing minerals into the water, temperature changes shifting chemical equilibria, seasonal changes in sunlight and atmospheric CO2 affecting growth of algae and phytoplankton...the list is quite long). Organisms that live in these sorts of waters have adapted to these seasonal effects, but there are also very significant volumes of ocean water that don't experience these large annual swings, and for which a 0.3 pH unit shift is a big change. Comparing a change in the average pH of all the Earth's oceans with variations in pH of comparatively small volumes in specific areas is comparing apples and oranges.
Instead of pH, let's consider a another property of the oceans: sea level. "Some sections" of the ocean (Bay of Fundy) have natural tides of 15 meters (50 feet). Despite that, a change of just one-fifth of that (3 meters, 10 feet) in worldwide mean sea level would cause some pretty serious problems.
The second sticky bit is that the writer seems to be glossing over the effect of adding a 0.3-unit change on top of an existing variation, shifting the mean and minimum pH downward. As noted, the pH scale is logarithmic. 5 times 0.3 is 1.5 pH units, corresponding to a (roughly) 30-fold change in concentration. 0.3 pH units, as noted, is an additional 2-fold change—that moves the maximum acid concentration to sixty times the original seasonal minimum. TenOfAllTrades(talk) 15:16, 7 June 2014 (UTC)
Trees are certainly cooler than the ambient air temperatures - so snuggling up against one of them ought to lose some heat. However, it's going to reduce the airflow over part of your skin surface - which will inhibit sweat evaporation and eliminate "wind chill". So, given our physiology, it might not be a net win. Much will depend on the air temperature and prevailing wind speed. Perhaps Koalas are like dogs and do not have sweat gland over most of their body as we do? If that's the case, then the downsides of tree-hugging wouldn't be as significant as it might be for us humans. It's a tough question to answer because it's so dependent on wind speed and ambient temperatures. SteveBaker (talk) 13:30, 5 June 2014 (UTC)
Give it a try, see how it goes. I'd think it would be of marginal use in an urban environment, but if you go out to a nice old forest, evapotranspiration keeps the whole area cool, and the trunks are even cooler. If you don't have a forest handy, a nice tall cornfield is also very cool, as they have a very high leaf area index. P.S. Lying flat on the ground is how squirrels lose heat: -- and it can work for humans in certain situations as well ;) SemanticMantis (talk) 14:45, 5 June 2014 (UTC)
What does pork have that beef and chicken do not have?
What is the chemical composition of pork, and how is the chemical composition of pork different from beef and chicken? It is known that some people are non-tasters, tasters, or supertasters of PTC. Is there a similar chemical in pork that would make some people avoid pork due to the repugnant taste or smell? 140.254.226.205 (talk) 13:34, 5 June 2014 (UTC)
I don't think the rationale is quite so straightforward (would ancient Jews even know what lobsters ate?), but I'm also not sure that's even what's being asked. Pork certainly has a very distinct smell and flavour, though that seems to have lessened somewhat as the rules for keeping pigs and what to feed them have tightened. As much as I love bacon, I could certainly see how someone who didn't like the smell/taste would be unable to get past it. Even if you don't care for chicken, the taste is so bland that it's probably something you could live with. But if you don't like pork? There's no hiding that or covering it up. Matt Deres (talk) 19:47, 5 June 2014 (UTC)
While pork certainly DOES have a chemical composition, i'm not sure discovering precisely what that composition is will give you any unique insight. In hindu culture, eating beef is forbidden and beef too has a unique chemical composition. The reason to prohibit any food has no logical explanation in the religious texts, at least much beyond “God says so” or it’s dirty or conversely: sacred. There are several “theories” as to why pork in particular is prohibited, but they are really just guesses that ‘sound good' and are logical, (like pigs eat carrion so are unclean (they don’t have to), or pig flesh resembles human flesh), however, the whole fundamental premise is illogical so trying to make logical sense of it could just as easily be a completely futile exercise. Vespine (talk) 04:53, 6 June 2014 (UTC)
Several notable cannibals, like Armin Meiwes, have actually likened the taste of human flesh to pork. Admittedly, others I have read likened it to veal, so I guess it depends who you ask, but you can't claim authoritatively that it doesn't taste like pork. Vespine (talk) 07:08, 6 June 2014 (UTC)
My understanding is that a large part of a meat's taste depends on the animal's diet. Pigs don't eat grass, and they do eat a lot of stuff that Chickes, usually cornfed, don't. The term "gamey" comes from the typical taste of game, rather than fodder-fed animals. One might also consider that pigs and humans have a higher and more mutually transmissible parasite load. Pretty much all fresh-caught whitefish tastes like chicken if eaten without freezing the same day it's caught. μηδείς (talk) 23:44, 6 June 2014 (UTC)
I'm not a hunter, but I'm told by those who are that deer whose diet is primarily leaves and twigs is not nearly as tasty as deer who've had access to cornfields. ←Baseball Bugscarrots→ 00:09, 7 June 2014 (UTC)
Flipping into "starvation mode".
I asked this question a while back and didn't get any useful answers - so I thought I'd try again.
Most weight loss diets caution you that dieting too aggressively can flip your metabolism into "starvation mode" - where it uses far fewer calories (or some say, absorbs calories from food more efficiently). However, they are all over the map on how much it takes to make this happen. Some caution you that skipping even a single meal can be counter-productive in losing weight because of this effect - others say that you should take a break from your diet every few months to avoid this effect...and yet others fall somewhere between those extreme positions.
Clearly they can't all be right. So, three questions:
Is there any scientific study to show how little food for how long it takes to flip this switch?
How effective is this metabolic shift in terms of calorie consumption to maintain steady weight?
What does it take to flip the switch back again?
Solid numbers from reputable sources are desirable here!
1) One thing to consider is that it may not be a single switch. That is, at different benchmarks different efficiencies kick in. One that's fairly well documented is that women stop having their periods at a certain low body fat percentage (see Amenorrhea#Hypothalamic), while others efficiencies, like how much glucose is used by the brain at various levels of caloric intake, might be harder to quantify (you'd need to starve people then give them PET scans, which would be unethical). StuRat (talk) 14:26, 5 June 2014 (UTC)
There are some very good and recent refs at Intermittent_fasting. Google scholar has plenty of good recent hits for /alternate day fasting/ as well. The overall trend of the findings seems to be that eating nothing(or much less) on alternate days can have specific demonstrable positive health effects. My understanding is that you have to look at the calorie intake as a time series. Eating a weeks' worth of food on one day and fasting the rest will almost surely trigger a starvation response. But (keeping total weekly calories constant) alternate day fasting seems to trigger no starvation effect, and actually increases fat metabolism. I of course haven't read all these papers just now, but skimming a few abstracts leads me to conclude that the suggestion that skipping one meal can trigger starvation response is just silly. SemanticMantis (talk) 14:55, 5 June 2014 (UTC)
"Eating much less than nothing" ? :-) As for skipping a meal, "starvation response" is not the correct term for it, but it might make you hungry enough that you eat whatever junk food comes your way, so could sabotage a diet in that manner. StuRat (talk) 15:01, 5 June 2014 (UTC)
I'm surprised that with glucose meters being so cheap and widely available, that there is not more discussion of using them for routine dieting by non-diabetics. Looking up such search terms online finds a few oddballs who say that yes, indeed, it provides a wealth of understanding, but I'm not having so much luck finding serious study of what happens when people adjust their diet plan in direct relation to specific blood sugar goals within the normal range. It's pretty well established that fasting or very low calorie diets are good when you have actual diabetes, because they put blood sugar lower - but if a dieter is having relatively low blood sugar and feels ravenous, I don't know that proves it's a good time for an indulgence, though I suspect so. Wnt (talk) 00:27, 6 June 2014 (UTC)
I believe calorie restriction was a treatment for diabetes before insulin injections became available. However, with insulin, there's no need to suffer all of the problems caused by a severely low calorie diet, such as lack of energy. Of course, diabetics do need to keep their weight down, as obesity is a causative factor in Type 2 diabetes and a contributing factor in Type 1. StuRat (talk) 05:41, 6 June 2014 (UTC)
What I'm thinking of is closer to , where a 4-day starvation diet is sufficient to restore the hypothalamic response to glucose ingestion, most probably increasing peptide YY production to make insulin more effective. This results in improved blood sugar levels with half the (endogenous) insulin level. Wnt (talk) 12:52, 6 June 2014 (UTC)
The -ane is generally used for the single-bonded hydrocarbons. The -ene is generally used for the double-bonded hydrocarbons. The -yne is generally used for the triple-bonded hydrocarbons. The -ane was proposed in 1866 by German chemist August Wilhelm von Hofmann (1818-1892) to go with -ene, -ine, and -one. They have no real meaning in themselves. Scientists can be creative, can they? 65.24.105.132 (talk) 19:15, 5 June 2014 (UTC)
OK, -ene is a Greek feminine patronomic suffix, -ane is coined from that and -yne is a variant of -ine which is "via French from Latin -ina (from -inus) and Greek -inē" (see their respective entries). Richerman(talk)19:33, 5 June 2014 (UTC)
65.24.105.132 and Richerman have answered the question between them. If their answers seem to contradict each other, it is because these suffixes have a dual etymology. Before 1866, the Greek suffixes -ene and -ine (-ήνη, -ίνη) were used in the names of various hydrocarbons (according to OED, -ane, suffix). The selection of the suffix probably depended on the discoverer's native language or on the history of the compound. For example, -ène was used in French-derived words such as methylène, while the Germans went for words like Benzin. The name of each hydrocarbon had its unique etymology. In 1866, Hofmann came along and proposed a system in which -ane, -ene, -ine, -one and -une had specific meanings. The first three are still in use (although -ine got changed to -yne by the International Union of Chemistry in 1931, according to OED-yne, suffix). So to return to the original question, -ane was entirely made up by Hofmann to extend the original set of Greek suffixes, -ene was copied by Hofmann from a Greek suffix that was previously not used in chemistry (it meant 'an inhabitant of', as in Nazarene; and I suspect that he first used it to adapt the German Benzin to his system); while -yne was entirely made up by the IUC in 1931 from Hofmann's -ine—again, -ine existed before 1866 but did not have a systematic meaning; it was derived from Latin -inus as Richerman has said and meant just generally 'an extract'. --Heron (talk) 11:56, 7 June 2014 (UTC)
"Spreading branches"
My guidebook on trees sometimes describes a tree as having "spreading branches". What on Earth is a spreading branch? What would a non-spreading branch be? That sounds like an impossible situation. Craig Pemberton (talk) 19:27, 5 June 2014 (UTC)
A stand of poplar, with upright columnar growth, not spreading branches.It's a description of the tree's habit, . Something like a lone oak has spreading branches, while e.g. a dense colony of poplar will have an upright structure. Elms are known for their 'vase shape'. This document from the USFS describes a few of the different terms, including 'oval', 'columnar', 'vase shaped', etc. . But really, check in the front of your book. There should be an introduction explaining the key terms. It might also have a gallery of silhouettes that give an archetypical example of each shape. This paper talks a bit about tree habits, and has some decent illustrations . Growth habit isn't actually a very good trait for beginners to use heavily, because habit is affected by local light and soil conditions as well as species, but it can help experts easily rule in/out certain species at a distance. SemanticMantis (talk) 19:56, 5 June 2014 (UTC)
Such as the larch, SemanticMantis? (I've added "http://" to your third external link to make it operative.) Another reason why growth habit is unreliable is that it is usually evident only in mature trees. A sapling or youthful oak, elm, and horse chestnut may have similar shapes, though mature ones may be distinguishable from quite a long way away. Deor (talk) 20:27, 5 June 2014 (UTC)
Why the polemic between Bible / evolution?
The Bible is full of strange theories, why is evolution at the center of the conflict science/religion? Couldn't the conflict orbit around some other biblical theory? OsmanRF34 (talk) 22:20, 5 June 2014 (UTC)
I suspect most contributors here on the Science desk, inevitably coming from a scientific perspective, wonder the same thing. The question really needs to be aimed at those religious folk who keep trying to pick the fight. HiLo48 (talk) 22:41, 5 June 2014 (UTC)
The concepts that would be in potential conflict with evolution would be the concept of a young Earth, and the concept that people have a different destiny than other animals; people go to heaven or hell while other animals don't. Are there other "strange theories" that are found throughout the Bible, rather than just in one or two passages? How many of the "strange theories" seem to be in conflict with physical evidence that is available to anyone who want's to visit a museum, as opposed to being in conflict with some other culture's version of history, or some other culture's myths? Jc3s5h (talk) 22:49, 5 June 2014 (UTC)
If you take the Bible literally to be a true story of how the universe and the Earth were created in a few days and how mankind was created in God's image and given dominion over the animals then evolution can't possibly be true. You can only square the Bible story with evolution by believing that the former is allegorical rather than the literal truth. The main reason why Darwin agonised so long before publishing his work was because he knew the problems it would cause in a Christian society. Richerman(talk)23:04, 5 June 2014 (UTC)
Obviously most religious believers do take the Biblical stories as allegorical, because most of them do not seem to see a massive conflict between religion and science. The issue only exists for a small subset of believers. The OP should ask them. HiLo48 (talk) 23:10, 5 June 2014 (UTC)
Thanks. I'm not American, and that's sad. I still say this is not a question for the Science desk, but one to ask of those "believers". HiLo48 (talk) 23:50, 5 June 2014 (UTC)
It's nothing to do with a young earth, plenty of old earth creationists do not accept evolution. The conflict is because it deals with "where we came from?" and "why are were here?". Is there any more fundamental question you can ask? Vespine (talk) 23:46, 5 June 2014 (UTC)(Edit:I obviously meant "why are we here?" it was a typo)
It is such a major point of conflict because of the obvious contrasts between the two concepts. Simply put, at face value, accepting one requires the inherent rejection of the other. It is also the easiest concept to argue against. Wholesale rejection of evolution makes one a willful ignoramus, wholesale rejection of Creation undermines the core concepts of one's faith, which is why there are a 101 different compromises and interpretations to balance them out. Plasmic Physics (talk) 23:59, 5 June 2014 (UTC)
Evolution isn't really at the center of it. Every time astronomers say that a galaxy is billions of light years away, or a geologist dates a non fossil, it's the same conflict. I do feel however that more can be done to reconcile the situation if people recognize that the timeline for the author's biography on the book jacket isn't the same as the timeline for the fictional characters in Middle-Earth. Wnt (talk) 00:15, 6 June 2014 (UTC)
The question asks about the controversy over evolution, as against other possible sources of controversy in the Bible. I have read all of the Gospels, and the book of Acts, as well as many other books of the NT, plus Genesis and Exodus, and various other books of the OT. Nowhere can I find anything that science could strongly challenge based on any historical or geological/paleontological evidence, save for the first 6 chapters or so of Genesis. There is simply nothing else to refute. The Resurrection might be scientifically inexplicable, but it is not hard to accept that an all-powerful God could suspend the laws of the universe once for his own son. The question is whether there is any way to refute it, since the only evidence is the testimony of a few people in the NT, and there is no claim that Christ appeared to any but his own disciples. That would suggest neither proof nor contradiction, since any differing accounts could be put down to different memories. That might present a theological challenge, but there is no scientific one. So if you allow for miracles, it is hard to use science. But it is different with evolution: if you deny that God miraculously altered the fossil record to make it appear as though the world were very old, then every fossil, every act of carbon dating, etc is still a serious problem. The only other thing that might be problematic is the story of Exodus, since it makes some very falsifiable historical claims, but this is not in the ballpark of the claims of Genesis. IBE (talk) 04:02, 6 June 2014 (UTC)
Undoubtedly. I meant to include it by the ref to Ch 6, although I didn't realise it went on for several chapters. So make that "first 9 or so chapters" IBE (talk) 08:20, 6 June 2014 (UTC)
On the other hand, if you suggest that God miraculously altered the fossil record to make it appear as though the world were very old, then you are implying by proxy that God is a false witness. What a pickle? Plasmic Physics (talk) 04:51, 6 June 2014 (UTC)
It's not an unreasonable idea. Day 1, God invents white light, comes up with a concept of "color", the spectrum, rainbows, refractions, reflections, and all manner of trippy special effects. The resulting Universe 1.0 might be a long video wonder of beauty in beauty, and probably some of the highlights still appear more or less unaltered in the current version, in nebulae, acid trips, the hues of chromium compounds. By version 3.0, God hashes out a concept of "matter", reworks the whole timeline beginning to end to include a fast, rather artificial process of planet formation, flat Earth, firmament, lots of kludges to allow a nice looking simulation where a Creator can work out things like whether mountains make more sense with the pointy end on the top or the bottom, and by the time the final release comes out there are even trees and grasses to give it all a really rich detail. Now to say that it's deceptive that this isn't visible in the history of the final version? I dunno, if you set up a character in that new Castle Wolfenstein game and he watches a TV newsreel of the war with the Nazis, would you expect it to look like a set of small black and white 2D frames with characters ticking along looting unseen schnapps from low-res treasure chests? That's just not how it works. As surely as we can create anything, we can understand to some extent what being a creator is like.
Of course, the science part that hangs us up is the question of how anyone would know what a previous version of the universe was like, and of course, any explanation we can give is really out there. Natural science should tell us nothing about it. But natural science can't tell us why we would "really feel" getting shot any more than one of those 2D characters in the original Castle Wolfenstein game. After all, both we and they are just electrical impulses directing the sound of an audible cry of pain. Consciousness remains unaddressed by science, the most common and significant and fundamental of all paranormal phenomena. But as long as its nature remains mysterious, we should take seriously the idea that people who seek after the true nature of things might be able to extract out of the Dreamtime some kind of understanding about how what is real came to be real and what is true came to be true. Wnt (talk) 06:30, 6 June 2014 (UTC)
I suspect that the problem is that the creation of mankind is the one story in the Bible that you can't easily dismiss. If you subtract any one of the other bible stories, you still have a viable religion. If we prove (and it's fairly trivial to do so) that there was no Noah's ark - then you say "Well, that's just an allegory - mostly a story for children" - and nothing much changes in your belief system. But if you deny that God created mankind - then everything else becomes rather shaky.
I recall that in the 1960's, people were very upset to hear that we are "descended from monkeys" - with some, even non-religious, people taking offense at this. Sadly, it gets worse, because we're also descended from various rat-like creatures, fish and maybe also some kind of slimey amoeba-like things. Not many things in science are such a radical slur.
That said, I'd have thought that people would be more rebellious at the idea that "free will" is essentially precluded by the laws of physics - but I'm not sure many people are aware of that - and even many serious scientists have a hard time taking that step.
Another possibility is that science has gradually pushed God into smaller and smaller roles. The "God of the gaps" problem. Every time physics explains something, it diminishes the amount of things that God might have done. God fits into the gaps where science has failed to deliver a sound explanation. A lot of religious people who are OK with evolution are unhappy to believe in abiogenesis (the step that took history from a bunch of chemicals floating in the primordial oceans to the very first replicating RNA molecule). This unexplained step in the chain from The Big Bang until present day gives them a "gap" into which they can squeeze their god. Science doesn't yet know how that abiogenesis step took place (although we have some ideas), so someone who wants to believe both science and religion, has a "get out clause".
But as science marches on, the number of those gaps is steadily decreasing. If we can figure out how abiogenesis happened, then we'll be able to explain everything from the first millisecond after the big bang until this very moment...so God will be squeezed into becoming the being who started things off at the beginning and never touched it again afterwards. Perhaps, seeing the writing on the wall, the fundamentalists have decided that "the buck stops here" at evolution. Even then, there are shades of reason...some people believe that evolution is true for all animals except humans, who were created by God. The science doesn't give any clue that this is true, but it's a way to insert a "gap".
For that to be true, this "God" would have to obey all of the laws of physics - bye-bye omnipotence and omniscience. At this point, the word "God" and the word "Physics" mean the same thing, and poof! we don't need religion anymore. The only reason you need this god-thing is if there are things you can't explain that lie outside of the laws of physics - and now you're back with God-of-the-gaps again. SteveBaker (talk) 20:50, 6 June 2014 (UTC)
Hmmm - they talk about "real chasms of plausibility that exist in Darwinian evolution" - I don't see any such chasms. Evolution is one of the simplest notions in science - and once you grasp it, it seems inevitable with the same degree of mathematical certainty as 2+2=4. It's not just "plausible", it's extremely hard to imagine how it could possibly NOT be true! Since their axioms are incorrect, the remainder of their argument is meaningless. SteveBaker (talk) 20:50, 6 June 2014 (UTC)
Once science has a clue as to the how of evolution, they'll be better able to counter arguments of the JW's and other literalists. ←Baseball Bugscarrots→ 21:07, 6 June 2014 (UTC)
Thermal question - longevity comparison of ice in a cooler
I was thinking about this the other day and it's one of those questions where I feel like the answer should be obvious but it's not to me. I have a medium-size cooler, one of those plastic jobbies that you can buy two or three small bags of ice for and keep your beer/soda cold all day while you go fishing or to the beach. Here's the question. For purposes of keeping the items cold longer, when I reach the point that the ice is mostly melted and I've bought two more bags of ice to add (thus once added I will have doubled the amount of H 2O in the cooler), which will last longer (or is it near equal): Me pouring off the still cold water in the cooler (without letting any of the ice still left our out) and then adding my bags of new ice, OR, adding the two new bags of ice to the still cold but almost completely melted existing contents? Please take it as a premise that the fact that the two tasks will take different amounts of time will have no significant effect on the results. If I've left off any information necessary for an answer, please advise. Thanks!--108.54.17.14 (talk) 22:20, 5 June 2014 (UTC)
If the ice is almost completely melted then the water, and hopefully the beer, will be at 0 degrees C. So, if you want to drink your beer before it reaches 4 degrees C then it seems likely that leaving the water in will delay warm up.
But it is more complex than that. The water is a better conductor of heat from the outside to the beer than ice, so to some extent this will offset the greater heat capacity of the ice box with the water in. I do not know which effect is stronger. Greglocock (talk) 23:19, 5 June 2014 (UTC)
The answer is add the ice to the water. The temperature outside of the cooler will be significantly warmer than inside the cooler and the rate of temperature change is proportional to the difference: The bigger the difference, the faster the change, in effect the colder it is inside of the box, the more loss you will get to the outside (well, that’s backwards, you are technically losing heat to the inside of the box, not losing “coolth” to the outside, but it’s essentially the same thing in this case). By tipping out the “warmer (but still cold)” melted ice you are throwing away a lot of the "coolth" and mass. Yes there are some complicating factors, but I've seen the experiment, probably on myth busters, and throwing out the cold water made the cooler warmer quicker. Vespine (talk) 23:44, 5 June 2014 (UTC)
I'd say that dumping the water may make the drinks colder initially, but for less time. Leaving the cold water in will make the drinks not quite so cold, but it will last longer. Of course, there are many other factors that go into the decision, like the weight, risk of spills, and possible other use for the cold water, like dumping it on yourself and clothes to cool down that way. StuRat (talk) 18:01, 6 June 2014 (UTC)
B.t.w., these sort of coolers are not all that good, they have rather poor thermal insulation, especially considering their weight. What I do when I need to keep things cool is the following. I take my rucksack, my winter jacket like this one, my thick wool sweater (which will keep me warm without a jacket at temperatures slightly below freezing) and a big plastic bag. I turn the jacket and the sweater inside out, close the zippers and move the jacket into the sweater. I put this in the plastic bag this then goes into the rucksack. The stuff that needs to be kept cool then goes inside the jacket in the rucksack. This is very lightweight and yet has a thermal insulation that is a lot better than that of traditional cooler. If you fill it up with your icepacks and a lot of beer, it may start to weigh a lot, but since it's all in a rucksack it's easy to carry up to a weight of 50 kg. Count Iblis (talk) 00:24, 7 June 2014 (UTC)
Styrofoam coolers have the advantages of being lightweight, effective, and inexpensive. On the downside, they are flammable and not very durable. You can also get a Styrofoam filled plastic cooler, but they are heavier and more expensive, too. StuRat (talk) 03:09, 7 June 2014 (UTC)
We can't see the circuit diagram. Possibly it's on your PC, but hasn't been uploaded to Misplaced Pages. Therefore, only you can see it. Use the "Upload file" link on the left side margin. If you have a 2nd computer with internet access, you can check it there after you upload it, to make sure it's really here. StuRat (talk) 17:54, 6 June 2014 (UTC)
The intensity of a beam of radiation travelling in a certain direction is related to its energy density by the formula , and it produces a radiation pressure of . Now, I know that if the radiation isn't travelling in a certain direction, ie it's thermalized and travelling outwards in all directions equally, then the radiation pressure will become . Will the formula for the intensity also pick up a factor of 1/3? 24.37.154.82 (talk) 15:18, 6 June 2014 (UTC)
Intensity is the energy flux emitted per unit solid angle, so this will be uc/(4 pi). The power emitted per unit area is then u c/4. To see this consider a small ball of radius r placed inside the encolsure filled with black body radiation. From each direction it will intercept radition with an effective cross section of pi r^2, so if you integrate over all solid angles, it will absorb a power of u c pi r^2 = u c (surface area)/4. Per unit surface area it absorbs a power of u c/4 which in equilibrium it also has to emit. Count Iblis (talk) 17:37, 6 June 2014 (UTC)
Electrostatic discharge
What's the mechanism behind things like sparks, lightning, St. Elmo's fire, etc.? I've heard two different explanations, both of which seem reasonable:
1) Stray electrons are accelerated by the potential difference created between eg the thundercloud and the ground. These electrons attain enough energy to ionize air molecules, creating more stray electrons which ionize more air molecules, and so on, creating an avalanche of electrons.
2) The potential difference is great enough to ionize the air (without needing say stray electrons), creating free charges which can then be accelerated by the potential difference to create a current.
"2" looks closer to right to me. (If "1" was correct, every spark would ignite the entire atmosphere.) However, I don't think you need to ionize the air to get a charge to jump from one object to another. I think that will happen in a vacuum, too. I believe the ionization is the result of the electrons jumping from one location to another, not the cause. I believe that ionized air does have less electrical resistance than normal air, so you do sometimes get double and triple lightning strikes, following a path close to the same one, each time. StuRat (talk) 02:57, 7 June 2014 (UTC)
See atomization. The most common meaning, as applied to things like perfume, is that it's made into a fine mist. And no, those droplets are not individual atoms. However, you probably meant the other meaning, which is also explained at that link. StuRat (talk) 02:54, 7 June 2014 (UTC)
See African forest buffalo (Syncerus caffer nanus). Taxonomists apparently at some point reclassified Syncerus nanus as a subspecies of Syncerus caffer. According to this page, both Bos nanus (from your first source) and Syncerus nanus are synonyms of S. c. nanus. (Nanus, by the way, means "dwarf" in Latin.) Deor (talk) 14:01, 7 June 2014 (UTC)
This book, at least, specifies that Liberia's national bird is, in fact, Pycnonotus barbatus. Note that both images in our article Common bulbul are of the "dark-capped" subspecies P. b. tricolor, which may account for the difference from the engraving on the stamp. Deor (talk) 13:44, 7 June 2014 (UTC)
How are gas and electric meter readings estimated?
I was too slow in submitting my gas and electric meter readings so they were estimated. Curiously, the estimated were exceedingly accurate for both. How is this achieved? Location: Edinburgh, supplier: Scottish Hydro. ----SeansPotato Business07:30, 7 June 2014 (UTC)
I would think they have several years worth of data on you, so they could make a pretty reasonable usage guess based on time of year and maybe other factors. ←Baseball Bugscarrots→ 07:43, 7 June 2014 (UTC)
They also know your address, so they know what the temperature was (which is the primary determinant of how much you ran the heating) and how much sunshine there was (which is the primary determinant of how much you had the lights on). In addition to your historical meter readings (for which again they know the prevailing temperatures and sunlight) they have those (and some real up to date readings) for some of your neighbours (who are also their customers) which they can use to validate their predictions. If there was some significant change in your domestic circumstances (particularly more or fewer people living there) or you made some marked change to the property (such as building an extension) that would throw off their estimates for a while. The predictive power of their model is such that if a property were to make a marked departure from the prediction that might indicate the premises were being used for other purposes. -- Finlay McWalterᚠTalk17:59, 7 June 2014 (UTC)
Formation of the Moon
If the Giant impact hypothesis is correct, would the Earth have been in a different orbit (or in any stable orbit) at the time of impact? Or would the Earth have been roughly in the same orbit that we know today? Dismas|09:55, 7 June 2014 (UTC)
It would have been in stable orbit, yes. The size of the impact would have been enough to significantly change the Earth's orbit, tilt, and rotation, depending on the direction of the hit and how off-center it was. An off-center hit is more likely to have changed the Earth's rotation (controlling day length) and tilt (causing seasons), while an on-center hit would have changed the Earth's orbit around the Sun more. To me, the Earth's orbit being roughly circular about the Sun suggests that it was not changed all that much, if we assume it started out circular. The tilt of the Earth and it's relatively fast rotation, on the other hand, do suggest an off-center hit. StuRat (talk) 12:37, 7 June 2014 (UTC)
There are other senses? I only know one sense. The first scientist would probable be some nameless homo erectus who learned how to control fire. Plasmic Physics (talk) 12:53, 7 June 2014 (UTC)
Or, perhaps there is an earlier example of when phytotherapy was first discovered, that is the use of plant materials for their curative properties. Any animal can potentially make that discovery. Plasmic Physics (talk) 13:04, 7 June 2014 (UTC)
It depends what criteria you use and who you ask. Accoring to Jim Al-Khalili, the first person to use the modern scientific method of acquiring new knowledge, or correcting and integrating previous knowledge, based on the gathering of data through observation and measurement, followed by the formulation and testing of hypotheses to explain the data, was Ali al-Hassan Ibn al-Haytham, born in AD 965. . Richerman(talk)14:11, 7 June 2014 (UTC)
Thales was the first to explain natural phenomena as the result of inanimate substances, rather than essentially psychological forces like love and strife. μηδείς (talk) 17:19, 7 June 2014 (UTC)
Resulting chemical from hydrogen + oxygen
Once you have hydrogen and want to combine it with oxygen from the air to produce electricity in a real-life environment: does the resulting chemical have to be water, or could you produce H2O2 or H2O3? I imagine that doing that would result in a higher electricity production, although you won't simply be able to release it in the environment. OsmanRF34 (talk) 19:30, 7 June 2014 (UTC)
I should think it would produce less electricity, as water is a more stable form. Therefore, producing less stable forms would require more energy, because you're fighting against the natural tendency. StuRat (talk) 19:47, 7 June 2014 (UTC)
, and it produces a radiation pressure of 
. Now, I know that if the radiation isn't travelling in a certain direction, ie it's thermalized and travelling outwards in all directions equally, then the radiation pressure will become 
. Will the formula for the intensity also pick up a factor of 1/3? 