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February 19

mixture of hair colours

What hair colour will a boy or a girl have as a result of his/her dad being a brunette and mom being a blonde? What hair colour will a boy or a girl have as a result of his/her dad being a redhead and mom being a blonde? What hair colour will a boy or a girl have as a result of his/her dad being a black hair person and mom being a blonde? What hair colour will a boy or a girl have as a result of his/her dad being a redhead and mom being a brunette? What hair colour will a boy or a girl have as a result of his/her dad being a black hair person and mom being a brunette? What hair colour will a boy or a girl have as a result of his/her dad being a black hair person and mom being a redhead? Will it be a mix of those two colours? Please answer and no discussion. Thanks. — Preceding unsigned comment added by 70.29.32.68 (talk) 01:45, 19 February 2015 (UTC)[reply]

Read This section of our article on human hair color paying special attention to the sentence that reads "The genetics of hair colors are not yet firmly established." There are several genes which determine human hair color, and your questions cannot be answered knowledgeably based only knowing the hair colors of the parents. There are some trends which establish some general trends of dominance (for example, dark hair tends to be dominant and lighter hair tends to be recessive) but there's really WAY too many factors at play which cannot be accounted for, and you simply CANNOT reliably predict, in a deterministic way, the hair color of a child solely knowing the hair color of their parents. --Jayron 32 02:35, 19 February 2015 (UTC)[reply]

72 hour pattern discovered

This is not a request for medical advice, so please don't offer it. This is a question about putative meteorological effects on physiological systems. To illustrate the problem, I will use myself as an example. Approximately 72 hours before we receive rain in Hawaii, I get a distinctive weather pain in certain areas of my body. I am not looking for any kind of medical advice. I am looking for an answer as to why this pattern of 72 hours consistently applies. Why not 24 or 48, for example? In other words, I get a certain weather pain 72 hours before it rains. Can anyone explain the significance of this 72 hour pattern? For example, what is happening meteorologically speaking at the 72 hour mark before the storm arrives and how does it impact living systems? I get the sense that I'm not alone, as my cat seems to feel it too. Viriditas (talk) 02:14, 19 February 2015 (UTC)[reply]

Not meteorological, psychological. Some combination of confirmation bias and placebo effect is probably at work here. --Jayron 32 02:29, 19 February 2015 (UTC)[reply]

I specifically linked to weather pains to prevent this kind of response. Have you read it? The meteorological effects on physiology are a scientific fact, neither psychological nor related to confirmation bias or placebo. I'm curious, on what basis would you make such an ignorant statement? Viriditas (talk) 03:39, 19 February 2015 (UTC)[reply]

As said below, the weather pains article doesn't support your claims. It suggests some people with certain conditions may be affected by certain weather changes. It doesn't suggest anyone is able to reliably predict rain exactly and always 72 hours in advance, instead of 71 hours or whatever, or 73 hours or whatever. Nil Einne (talk) 11:19, 19 February 2015 (UTC)[reply]

I never said any or insisted on any of those things. I think you are interpreting my words a bit too literally. I specifically asked about meteorological conditions at approximately 72 hours leading up to the storm and their effects, which StuRat directly addressed in his reply. Viriditas (talk) 19:17, 19 February 2015 (UTC)[reply]

When ever anyone reports a phenomenon based solely on their personal experience, confirmation bias is the only reasonable conclusion. Scientific reliability requires things like falsifiability and double blind trials and things like that. Beyond that, we have NO WAY of explaining why you experience the unexplained thing you are experiencing. You're aware of weather pain, which is a documented phenomenon. However, when we're dealing with the experience of one person, the only reasonable thing to do is focus on what can explain a unique experience of one person. One's own unique experience can only be explained by first looking for the most likely explanation: that your unique and heretofore unexplained experience is due to an internal process in your head (confirmation bias!) and not due to any scientific universal. If it were due to a scientific universal it would have already been established as such by the multitude of people who had the same experience and would be reported in articles like weather pain already. --Jayron 32 02:36, 20 February 2015 (UTC)[reply]

Actually you did. When Jayron32 offered perfectly resonable explainations for your claims, you reject them for no good reason and only linked to the weather pains article, despite the fact it was irrelevant to the point Jayron32 was making. Nil Einne (talk) 15:38, 20 February 2015 (UTC)[reply]

This sounds like folk tales (possibly true) of people whose arthritic knees would flare up when a storm was approaching. I think a lot of that is attributed to subtle changes in atmospheric pressure, humidity level, etc. As regards 72 hours, I don't trust any weather forecast that's more than a few hours old. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:40, 19 February 2015 (UTC)[reply]

Weather pains are not folk tales. Did you read the link I provided? Clearly, you did not. The question about 72 hours regards the exact meteorological conditions and why it would start 72 hours out. It may be, for example, due to Hawaii's proximity in the Pacific and the coastal effects due to the volcanoes (orographic precipitation). I don't know the answer, but the replies up above are absurd. Viriditas (talk) 03:39, 19 February 2015 (UTC)[reply]

Your link calls it "folklore", which might be the better term. Either way, folk wisdom is not necessarily false. Let me ask you this: How far ahead would you consider local, conventional weather forecasts to be reliable for Hawaii? I would think more so than in the mainland. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:05, 19 February 2015 (UTC)[reply]

Hawaii weather is pretty predictable. In other words, partly cloudy with scattered windward and mauka showers. It's very boring. Actual storms are rare...and painful. Viriditas (talk) 09:42, 19 February 2015 (UTC)[reply]

See above and below. There's a big difference between weather pains which our article discusses and mentions does have some scientific support, and claiming someone can reliably predict rain 72 hours in advance, but not 71 hours or less or 73 hours or more for which you've so far presented zero evidence in support. The responses here seem mostly fair. Noting that while BB did call them folk tales, they also suggested they may be true. It may have been best if BB read the article before responding, but still what's more absurd is to make a claim without evidence and refuse to accept suggestions you may be wrong. Nil Einne (talk) 11:19, 19 February 2015 (UTC)[reply]

There's nothing to be right or wrong about, so your comment doesn't make sense. My question specifically has to do with meteorological conditions approximately 72 hours before the storm, which has been answered by SuRat. What evidence am I supposed to provide in this discussion other than the study indicating it is possible? I'm not here to ask about the evidence, only the meteorologic effects. Viriditas (talk) 19:17, 19 February 2015 (UTC)[reply]

The thing is, you keep insisting people are wrong when they point out there's far more resonable explainations for your claims. You've provided no evidence for these claims, despite you being the one who came here to ask a question, but when people gave mostly resonably replies you started insisting they were wrong despite having no reason why they were wrong. You link to the article weather pains, which is largely irrelevant to the point people were making. Nil Einne (talk) 15:38, 20 February 2015 (UTC)[reply]

No physical process reliably predicts rain three days in advance. Weathermen would love it if there was. That said, there might be environmental changes that occur a few days before rain often enough that you notice it. Given its mild climate, I suspect you would already have noticed any temperature swings large enough to be important. So if we discount ambient temperature, the most likely physiological agent is probably pressure variations. I would suggest looking up the barometric pressure at times when you feel "weather pains" and comparing those values to the typical pressure over longer time periods to see if you can see a pattern. If you already have a list of times you've experienced it in the past, you could also look up historical values for pressure. Dragons flight (talk) 04:06, 19 February 2015 (UTC)[reply]

This study supposedly shows people with joint pain predicting rain. Does anyone have access to it? Viriditas (talk) 09:35, 19 February 2015 (UTC)[reply]

Probably everyone with an web browser, internet access and a PDF viewer? The full text PDF is linked in that page and seems to be available for free and isn't behind a paywall as far as I can tell. It doesn't seem to suggest anyone is able to reliably predict weather 72 hours in advance and for that matter exactly 72 hours and not 74 hours or 70 hours. Nor does our article. So your responses above to other respondents are fairly confusing. Nil Einne (talk) 11:06, 19 February 2015 (UTC)[reply]

You seem to be getting hung up on the time frame for some reason. That study shows people using their pain to reliably predict rain. In my case, my question has to do with meteorological effects on the body 72 hours before the rain occurs. Viriditas (talk) 19:17, 19 February 2015 (UTC)[reply]

I admit insisting 72 hours instead of 71 or 73 hours was largely facetious and I missed your approxiamitely bit. The general point stands though, and you can easily replace 71 with 48 and 73 with 96. I think we can be sure that even if predictions in Hawaiʻi are more reliable than elsewhere, there is nothing that always happens at 72 hours instead of 48 or 96 hours. E.g. [1] [2] [3] [4]. Nil Einne (talk) 15:38, 20 February 2015 (UTC)[reply]

I wonder why 72 hours rather than, say, 73 or 66. Even on Star Trek pretty much everything happens in multiples of 12 hours. —Tamfang (talk) 04:47, 19 February 2015 (UTC)[reply]

It wasn't meant to be taken literally. I see my audience has once again had a predictable reaction. I used the word "approximately" for good reason. Viriditas (talk) 19:17, 19 February 2015 (UTC)[reply]

The heading doesn't say "approximately". And you would have been better off saying "about 3 days" instead, as 72 hours sounds a little too specific. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:04, 19 February 2015 (UTC)[reply]

Low pressure associated with rain could certainly cause pain, but that should only be a few hours before the rain arrives. At 72 hours before, you might be at the height of the high pressure between storms. Maybe you react like that to high pressure. Now rain systems here are rather chaotic in timing, but maybe there they follow a more predictable pattern. StuRat (talk) 07:06, 19 February 2015 (UTC)[reply]

It's fairly well established that some people feel joint pain when the air pressure drops abruptly. The issue here is whether rain occurs 72 hours after such a pressure drop at a sufficiently high probability to convince our OP. Certainly meteorologists can measure air pressure just as effectively as someone with joint pain - since we know that they cannot (In general) predict with that kind of accuracy three days in advance, it cannot be that our OP can reliably predict rain in that manner. HOWEVER, it might be that in some very simple weather situation (and an island in the middle of a large ocean is a fairly simple thing, meteorologically-speaking), this degree of reliable prediction is possible. It's certainly plausible that (say) three days ahead of landfall of a rainstorm in Hawaii, there is a 90% probability of a pressure drop. That wouldn't help in predicting the weather in the middle of a large land-mass (for example) - which explains why (on average) the meteorologists can't make that prediction - but perhaps, in this case, it does.

That changes this question into one of: Are rainstorms in Hawaii reliably preceded by a drop in pressure - and how long before the rain event does that typically occur?

Sadly, I can't answer that one - but that is the key to understanding what our OP is saying here. SteveBaker (talk) 20:53, 19 February 2015 (UTC)[reply]

Not sure why you say weathermen can't predict rain 3 days in advance. My local weathermen often do, although when they say there's a 50% chance of rain, you can never really say they were wrong, can you ? StuRat (talk) 03:23, 22 February 2015 (UTC)[reply]

When they say "such-and-such percent chance", that's usually a shorthand way of saying that historically the current conditions have resulted in their prediction "such-and-such" percent of the time. Compare that with temperature predictions, which are similarly guesstimates, and can be off by a few degrees, but that's less important than what it might do in conjunction with precipitation. "50 and rainy" is a lot less concerning than "32 and raining." ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:19, 22 February 2015 (UTC)[reply]

Banana spiders - season for spinning webs

Banana spiders, such as Golden silk orb-weaver spin their webs seasonally. In what months (in the northern hemisphere) do they spin their webs? Bubba73 ^{You talkin' to me?} 02:28, 19 February 2015 (UTC)[reply]

Are Chicory and belgian endive one and the same?

The article Chicory contains pictures of Belgian endive with root, and yet both seem very different from the few apparent images... So... What's going on here? Can someone please explain in simple words?... [PLEASE sign your posts, Ben-Natan

Cichorium_endiva
Witloof, Belgian endive

It's a highly variable species, like the Canis domesticus (dog), Columba livia (pigeon), Carassius auratus (goldfish), or Brassica oleracea (cabbage, broccoli, cauliflower, kale, Brussels' sprouts). μηδείς (talk) 04:41, 19 February 2015 (UTC)[reply]

Yes it's variable, but the witloof form is produced by forcing the chicons. To do this, you put a chimney pot over them so they grow white (as they're not exposed to sunlight they don't produce chlorophyll), crisp and compact. Unforced chicory grows into the form in the left hand picture. The process is known as etiolation I believe. --TammyMoet (talk) 10:56, 19 February 2015 (UTC)[reply]

Ah, kind of like making goose-liver pâté. There is a term for organisms that can take on radically different morphologies depending on the condition in which they develop, but I can't think of the term off the top off my head. μηδείς (talk) 17:39, 19 February 2015 (UTC)[reply]

Nice!

I had the feeling that they use such stencils... Anyways, one more reason I asked the question was that I read somewhere (in Hebrew I think), that the Witloof roots isn't edible compared to "Chicory" root but either I remember false information or what I read was just wrong. Ben-Natan (talk) 13:24, 19 February 2015 (UTC)[reply]

Well as witloof = chicory I don't know where you got that from. Chicory root, if ground up, makes a passable coffee substitute. I wouldn't like to use it as a potato substitute though.--TammyMoet (talk) 11:01, 20 February 2015 (UTC)[reply]

How to collect water vapor in the desert?

Deserts are known to be hot and dry, but in the evening thew temperature seems to be cool and humid; with some amount of water vapor in the atmosphere. can there be any way of trapping these water vapor in huge quantity which will be beneficial to people living or traveling in the deserts?Momoh G. Musa (talk) 06:22, 19 February 2015 (UTC)[reply]

There's only a little water vapor in the dessert, but the temperature does drop dramatically at night, potentially producing dew or frost. A large plastic sheet in the form of funnel with a bottle at the bottom can therefore collect some water. However, it's not "huge quantities". You'd need a very large surface area of plastic sheeting just to provide enough water for one person. Also note that this collection method may bring dust and sand into the bottle, as well, so you may need to filter and/or sterilize the water. And if there's a sandstorm, the entire apparatus will be blown away or destroyed. StuRat (talk) 06:51, 19 February 2015 (UTC)[reply]

It's called a fog fence.--Shantavira|^{feed me} 09:14, 19 February 2015 (UTC)[reply]

That method is actually used along the Pacific coast of South America, where there is virtually no rainful but dense fogs often form. One way of turning the fog into water is a fog fence, as Shantavira mentioned, but needle-leaved trees are also effective. If you stand under a tall pine tree in a dense fog it can feel like it is raining. Our article on fog collection discusses some of this, although it is written in a rather unencyclopedic way. Looie496 (talk) 17:48, 19 February 2015 (UTC)[reply]

Is it possible satellite (sputnik) tracking for general radio and TV broadcasting?

Did it been matter for satellite (sputnik) tracking for general radio or TV broadcast on high-frequency or low-frequency waves range is being the radio or TV broadcasting?--83.237.216.141 (talk) 11:21, 19 February 2015 (UTC)[reply]

Hi Alex. Are you asking whether Radio frequency broadcasting interferes with satellite tracking? (I expect it does, but only to a very limited extent.) Or are you asking if whether broadcasts from satellites are used for radio and TV? (the answer of course is yes, see Satellite television). Or are you asking about the broadcasting of Satellite watching? (probably not). Or are you asking about using Global Positioning System satellites for tracking or a Vehicle tracking system or other GPS tracking unit? Or something else? Dbfirs 15:51, 19 February 2015 (UTC)[reply]

I was tempted to respond, but I was waiting for a translation into English. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:30, 19 February 2015 (UTC)[reply]

I tried translating into Russian and back into English, but Google wasn't helpful: "Is not this was the case for the satellite ( Sputnik ) track the total radio or television broadcasting in high-frequency or low-frequency waves vary currently vremyaradio or television broadcasting ?". Dbfirs 17:54, 19 February 2015 (UTC)[reply]

For further info on trying to translate from English nonsense to Russian sense, see GIGO. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:01, 19 February 2015 (UTC)[reply]

My interpretation was "Did Sputnik broadcast it's signal at a frequency which could be picked up on radios or TV ?", but with Alex, anyone's guess is as good as mine. (The answer, BTW, is yes, it could be picked up on radios as it flew over.) StuRat (talk) 18:04, 19 February 2015 (UTC)[reply]

Sputnik broadcast a signal on 20 and 40 MHz. 20 MHz will be often found on a shortwave receiver dial. So it could be received. 40Mhz is at the low end of VHF, and not on frequencies used for radio or TV broadcasting around here. Graeme Bartlett (talk) 22:12, 19 February 2015 (UTC)[reply]

Thankful! In general question, did it been matter the radio frequency waves range for solving technical problems?--83.237.209.24 (talk) 12:28, 20 February 2015 (UTC)[reply]

So, I believe that the radio frequency waves range did not it been matter for solving technical problems, because the speed (inductance) of the signals in the wires is always been greater (maximus).--83.237.222.77 (talk) 14:27, 20 February 2015 (UTC)[reply]

Since all radio waves are always had a dual nature as light, so that the radio frequency waves range did not it been matter for solving technical problems!--83.237.243.184 (talk) 16:17, 20 February 2015 (UTC)[reply]

Radio waves certainly have a dual nature as particles, but it's nearly always easier to treat them as waves. Light is a different frequency. See Electromagnetic spectrum. Dbfirs 17:27, 20 February 2015 (UTC)[reply]

Thanks. Quantum paradoxes had a good explanation why the radio frequency waves range did not had a matter in technical applications.--85.141.238.90 (talk) 18:42, 20 February 2015 (UTC)[reply]

And also nobody did not been excluding particular cases in quantum paradoxes.--85.141.238.90 (talk) 18:50, 20 February 2015 (UTC)[reply]

So, did it been matter for satellite (sputnik) seeking the radio frequency waves range?--85.141.238.90 (talk) 19:12, 20 February 2015 (UTC)[reply]

Radio waves are certainly used in technical applications. The satellite radio would have been designed using radio engineering principals. Quantum mechanics does not come into this work. The photons in radio waves are so numerous that an average in a wave is a very good model. One of the few places where the quantum nature comes into effect is the MASER. Some emission or absorption lines can appear in the radio spectrum, but normally in microwaves, far above the Sputnik frequencies. So it did not effect Sputnik. Important aspects would be the ionosphere and the publicity effect of choosing a frequency that thousands of people could receive. General radio and TV broadcasting from satellites is limited by the power from the satellite, which is small. This then requires a large antenna on the ground. Yet there are systems. like Sirius Satellite Radio. Graeme Bartlett (talk) 21:39, 22 February 2015 (UTC)[reply]

To those with knowledge in Biochemistry, Endocrinology, or Internal Medicine

Please see Talk:Hyperinsulinemia. Ben-Natan (talk) 13:26, 19 February 2015 (UTC)[reply]

My only specialty here is being a type II diabetic and having a BA in biology, although I focused on botany. μηδείς (talk) 22:03, 19 February 2015 (UTC)[reply]

Boltzmann brain

What exactly is this article talking about? Is this some sort of thought experiment in the same vein as Einstein's relativistic train or an actual proposed possibility? This sounds like what happens when physicists try their hands at philosophy. — Melab±1 ☎ 15:09, 19 February 2015 (UTC)[reply]

It's a thought experiment, but unlike e.g. Schrodinger's cat, Boltzmann Brains might well be out there. We just can't know. Same goes for Russell's Teapot or the Invisible Pink Unicorn. The Boltzmann Brain can also be considered as a paradox, though there are different interpretations and potential resolutions. If you like this sort of thing, you may like to read about Roko's basilisk ([5]). But now that you know about it, you might suffer in the future if you do not support AI research ;) SemanticMantis (talk) 15:42, 19 February 2015 (UTC)[reply]

In an infinite worlds universe, Boltzman brains should exist in some of them (in fact, in an infinite amount). StuRat (talk) 16:34, 19 February 2015 (UTC)[reply]

That's not true, Stuart. An infinite set of infinite sets does not necessarily contain any one specific object. Lets say the Boltzman's Brain configuration could be described as the number π^{8,546,952,522,455,111,230,709,123,576,420,007}. You could easily have an infinite number of infinite sets that do not include this number. An infinite number of Chimps at an infinite number of typewriters over an infinite time will never get you a full play by Shakespeare, since they will type an infinite number of things like complaints to OSHA about their working conditions instead. There's also the fact that the BB idea presumes consciousness is a simulation but a simulation of a brain will be no more conscious than a simulation of a hurricane will blow your house down. The whole project if rife with (ironically) epistemological rationalism, reductive materialism, question begging, stolen concepts and category mistakes.— Preceding unsigned comment added by Medeis (talk • contribs)

That's kinda true - but in an infinite set of infinite sets of objects-created-by-quantum-fluctuations, the probability of any specific object not being there approaches zero. So, sure there is a chance that there are none - but it's an infinitesimal chance that we may safely neglect - and in fact, there is only an infinitesimal chance that there aren't an infinite number of boltzmann brains (and also boltzmann elephants, boltzmann plays by Shakespeare, etc). It would be different if there were laws of physics preventing such a thing - but there aren't - it's just a matter of chance. As for the chimps - even in an infinite universe, the chances of OSHA actually *doing* something is still zero, so that play will still appear an infinite number of times. SteveBaker (talk) 19:37, 19 February 2015 (UTC)[reply]

No, because approaching zero (as well as infinite) is undefined in actual existence. I can have an infinite set of texts that even vaguely resemble parts of what Shakespeare wrote, and still have for each of them an infinitely infinte set of texts which don't. Infinity in no way guarantees the actual existence of any specific concrete/token/text/member. Good OSHA joke, however. The one thing they do do is issue fines. μηδείς (talk) 20:10, 19 February 2015 (UTC)[reply]

Suppose I roll a million dice, and don't get a six - unlikely, but it could happen. Suppose I roll a googolplex of dice and don't get a six - really, REALLY unlikely but still possible. Sure, it's possible to never get a six (or a Shakespeare play) with an infinite number of die rolls - but the probability of never getting one is infinitesimal. Specifically, the odds are 1/infinity - which isn't zero, but it's definitely close enough that we can ignore the chance that you won't get a 6. Since we're hypothesizing that boltzmann brains come about through random quantum fluctuations, the odds of NOT getting one with an infinite number of rolls of the quantum dice is infinitesimal too. You're right, there isn't an absolute guarantee that you'll get a six on that infinite pile of dice - but the probability that you won't is UTTERLY negligible, no matter how you slice it. So, the odds that there isn't a boltzmann brain in an infinite universe and Medeis is right is 1/infinity - and the odds that there is at least one and Steve is right is 1-(1/infinity). I imagine that everyone knows who to bet on here! SteveBaker (talk) 20:42, 19 February 2015 (UTC)[reply]

You are assuming a defined universe of six states, and asking what the chances are in 1,000,000 independent iterations of that universe are of not rolling a six. That's a very small, well-defined calculation for which an easy calculation is quite available. But we don't even have a definition of what a brain or consciousness is in the brain scenario (BS). First, only a mathematician would think that consciousness is a set of numbers, or a physicist that it's an arrangement of particles.

A brain, so far as we know by facts, is an extremely complex organ, in a body, standing in a certain relation to physical reality. A brain in a vat is a specimen in a morgue or a museum. Consciousness is a property of a living embodied brain in relation to its environment over time, after a long period of ontological development. Your consciousness now of what I am writing was in part caused by your being taught to read around age 6, perhaps decades ago.

To call consciousness a mathematically compressed snapshot of some current brain state is absurd in the extreme, and totally divorced form anything known to neurologists and physicians. The BS "experiment" assumes a philosopher knows the nature of brains and consciousness, when he doesn't. The BS "experiment" assumes a very limited digital simulation at one instant, rather than real particles in real time. The BS is simply not worth talking about if one is interested in empirical reality, let alone mathematics. μηδείς (talk) 22:35, 19 February 2015 (UTC)[reply]

If we flip infinite coins, we can say that one of them comes up heads, almost surely. Likewise, flipping infinite coins and getting no heads happens almost never. This is the standard language of mathematical probability, axiomatically constructed from measure theory, and we're essentially saying that the bits of the sample space that correspond to the event of no heads has measure zero. Unfortunately, we can't really use axiomatic probability for this thought experiment, that's why physicist-philosophers like to argue about it. SemanticMantis (talk) 21:24, 19 February 2015 (UTC)[reply]

Hmmm, this is confusing. On one hand it's easier to say that a fluctuation could more readily produce a lone disembodied brain than a whole self-consistent universe. But on the other, well... suppose you have a superposition of all possible universes that could have formed, and you haven't learned anything about it. Now you find out one fact, that there's a brain in it, with the "state-vector collapsing" to reflect that fact. Well, shouldn't that brain be most likely to have the most likely history by which it could have arisen, i.e. via a process of evolution as part of a living organism, rather than a fabulously unlikely random coalescence of particles? So I'd like to see some more about how that statement about probability came to be made. Wnt (talk) 19:20, 19 February 2015 (UTC)[reply]

The thing is, if we exist merely as thoughts in a boltzmann brain, then the universe is basically just a minor variation on the simulation hypothesis - which basically says that our universe is just a simulation running in a computer somewhere in the real world. Similar arguments apply - if we were able to create a simulation of a universe (something we're starting to do fairly routinely in video games) - then it is highly likely that we'd make more than one of them...so there would be more simulated universes than real ones...since simulated universes can in turn evolve to the point where they make their own simulated simulated-universes (ad nauseam), the probability that our universe is the real one is likely to be very small. I actually think that the evidence for this is quite compelling. Things like quantum randomness, the arbitrary speed-of-light limitation and the metric expansion of space are all EXACTLY the kinds of thing you'd build into a simulation in order to make it less computationally expensive. Then there is THIS interesting new work suggesting that the energy density of the universe may depend on the amount of data required to describe it...which would fit very well with us being in a virtual universe where only the amount of data it takes to describe it is what matters. People complain that the "real" computer that runs all of this would have to be quite utterly insanely large and fast - but the laws of physics in the "real" universe might make that easily possible (eg, if the speed of light were infinite there). So, whether we're an imaginary universe being imagined by a boltzmann brain - or a video game running on a laptop in some spotty teenage alien's bedroom on the third moon of Zirktron-5 in a universe which (in turn) is being run by a bored office worker over lunchtime in his accounting job on the perpetual iridium slopes of the high mountains of Phtttbbbtphttttf-19 makes very little difference. SteveBaker (talk) 20:20, 19 February 2015 (UTC)[reply]

I don't really understand where you're getting your probabilities from either. Suppose all we know about the cosmos is that there's a brain which is getting the sensations of typing on a keyboard, looking out the window, seeing crows fly past and so forth. Now a priori, is there some reason you can express why it's more likely that these things are produced by some randomly created elaborate computer simulation mechanism to make the impulses corresponding to these things out of some sort of virtual reality, than for there simply to be a planet with buildings and windows and crows and a self-consistent, material world history behind them? I feel like you're making the assumption that "you can't move around anything big" to get the universe to match the brain, but that seems unreasonable. The moment you open the universe-in-a-box you're making it so the stars are here, not there (if there are really any stars that is); you're completely affecting the entire distribution of everything throughout it, I'd think. Wnt (talk) 21:10, 19 February 2015 (UTC)[reply]

Sean Carroll's three-sentence summary of the argument is:

Certain cosmological scenarios predict that it’s more likely for a brain like yours or mine to arise as a random fluctuation, rather than through orderly evolution.
Our brains aren’t like that.
Therefore, those scenarios are not correct.

The reason some cosmologies (specifically eternal inflation) make that prediction is that they have regions of vacuum that are much larger than the regions where evolution could take place (such as the one we're in). -- BenRG (talk) 21:43, 19 February 2015 (UTC)[reply]

The second bullet point is not quite right, actually. We don't know we aren't like that so much as we assume it in everything we do, including science. E.g. the existence of dinosaur fossils is consistent with dinosaurs having existed but also with that arrangement of atoms having arisen by chance with no preceding living animal. If a cosmology says that the latter possibility is a priori more likely than the former, then you may as well reject that cosmology, because if it's wrong then you're right to reject it, and if it's right then science is meaningless and it doesn't matter what you reject. -- BenRG (talk) 22:55, 19 February 2015 (UTC)[reply]

Ignorance is not a claim to knowledge, no claim follows a priori from "We don't now." μηδείς (talk) 00:07, 20 February 2015 (UTC)[reply]

Human teeth and spider silk

I'm obviously missing something here. This University of Portsmouth graph cited by The Independent (slightly below the headline) shows that spider silk is about 8 times stronger than human teeth. However, since tensile strength also means stretching stress, a thread of spider silk can be fairly easily torn apart, unlike human teeth. What's going on actually? Brandmeister^talk 16:26, 19 February 2015 (UTC)[reply]

You are comparing different amounts. They are saying, I believe, that if you had a spider web braided to the thickness of a tooth, it would take 8 times as much force to break it as a tooth. StuRat (talk) 16:30, 19 February 2015 (UTC)[reply]

From tensile strength

“

The UTS is usually found by performing a tensile test and recording the engineering stress versus strain. The highest point of the stress–strain curve (see point 1 on the engineering stress/strain diagrams below) is the UTS. It is an intensive property; therefore its value does not depend on the size of the test specimen.

”

-- emphasis mine. Also note that the graph is in pascals, which have units of newtons per square meter, also indicating that the tensile strength takes cross-sectional area into account. But, in a sense, your point is still correct. If we want to apply 4 GPa to a human tooth, that will be much more force (in newtons), than applying 4 GPa to a strand of spider silk. (Also, let's forget about braiding. Braids, twists, knots, etc. all can radically change the tensile strength of cordage.) It's a shame we don't have an article Orders_of_magnitude_(tensile strength), perhaps someone would like to use the data in the linked article to start a stub. SemanticMantis (talk) 19:33, 19 February 2015 (UTC)[reply]

I think this comparison to teeth is a bit of pop science, and this is why. Tooth cementum is reported to have widely different mineral contents (I just found it listed as 65% mineral content by weight in the Lindhe perio textbook, whereas the AAP (American Academy of Periodontology) in-service exam lists it as 40-50%. The problem here is that bone is reported to have a mineral content of 60% by weight and these two reported values for cementum are on opposite sides of this value. Be that as it may, in dentistry, it's a fairly commonly discussed phenomenon that cementum is harder than bone, dentin (the internal core component of teeth in humans and most other animals) is harder than that (usually listed at somewhere near 70% mineral content) and enamel, which covers the crowns of teeth in almost all species, is even harder than that at around 95% mineral content by weight. Whatever the exact data is, it's a thoroughly established scientific fact that teeth are the hardest substance in the human body under normal physiologic conditions (see this for something even harder, but this hasn't been demonstrated in humans and would not be physiologic for humans even if it were, but I digress). The point being that teeth are known to be very hard and so are said to be very strong, but teeth are hardly uniform in component thickness and there is much more enamel on, say, a molar than there is on a mandibular incisor. And the discussion above seems to focus on tensile strength and not at all on compressive strength. I'm no engineer or materials scientist, but from what we learn in dental school, the two are very different and, again, in general, the compressive strength yield is either always or usually much greater than the tensile strength yield. But who's trying to crush spider silk? Maybe if you try to make a bullet proof vest out of it, but as I consider this question, it seems that we try to pull at spider silk but crush teeth, and so we're very likely referring to tension here and compression there, and that's not really a fair comparison. But for pop science, people like to have quick quote facts to spit out, like saying "did you know that spider silk is X times stronger than steel?" I mean, fine -- that's a cool talking point, but I think it largely misses the real science of it, and your question seemed to touch upon the real science of it, so I thought I'd throw this into the mix. DRosenbach ^{(Talk | Contribs)} 20:57, 19 February 2015 (UTC)[reply]

So if I got it correctly, the spider silk outperforms the teeth by strain magnitude? But if the UTS value doesn't depend on the size of the test specimen, it turns out that comparing an entire tooth and a strand of spider silk is fair? Brandmeister^talk 21:18, 19 February 2015 (UTC)[reply]

The silk would outperform the tooth in UTS, which is in pascals, regardless of size. However, the force necessary to pull apart ordinary spider silk is less than the force necessary to pull apart the tooth. I think you're just confused about the units. Delivering 1 GPa to a 0.1 mm^2 cross section of silk strand requires less total force than delivering 1 GPa to a ~ 1cm^2 cross section of tooth. It would probably be a good exercise in dimensional analysis to come up with some answers for breaking force in newtons for both a strand of silk and a tooth, based on the data published and some estimated cross sections. If you want to compare UTS and get a clear winner in terms of force, then you have to consider samples of the same cross section. DR's points about inhomogeneity and variability of teeth still apply, we can probably safely assume that all of these UTSd data are mean values calculated over a range of samples. SemanticMantis (talk) 21:30, 19 February 2015 (UTC)[reply]

And apparently the Limpet has them both beat. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:26, 19 February 2015 (UTC)[reply]

The trash or the recycle bin?

Plastics, aluminum, and paper go in the recycle bin - sometimes labelled "All-In-One". Food wastes - which are organic materials - usually go in the Trash bin. Now, if you find a deceased cat on the ground, and it is wearing a collar, is it safe to remove the collar and dispose it in the plastics/aluminum/paper bin and the body in the Trash bin? What happens if you find a deceased human being wrapped in a blanket? Where should that go? Is the plastics/aluminum/paper bin the same thing as the compost bin for dead leaves and other organic matter on your front lawn? 140.254.136.182 (talk) 20:51, 19 February 2015 (UTC)[reply]

You should leave the collar on a deceased cat until it gets tagged at the morgue so we know what its name is until it receives a assignment number. After that, the collar can be recycled by using it on another cat -- it needn't be melted down to form a spoon or a a wire casement. DRosenbach ^{(Talk | Contribs)} 20:59, 19 February 2015 (UTC)[reply]

... and, of course, deceased humans that you regularly find wrapped in blankets go to the police first, not in the compost bin with the dead leaves, nor in the separate recycling containers for plastic, aluminium and paper. Dbfirs 22:53, 19 February 2015 (UTC)[reply]

Rules about what goes in which recycling or other waste bin, as well as what range of bins the Local Authority provide to householders, varies widely even between adjacent districts in England: major details differ between my parents' address, my own address and my workplace address, which lie within an overall distance of less that 20 miles but are each in a different Local Authority area in Southern England.

Similar variations probably occur worldwide. Any meaningful answer, therefore, will be extremely location-dependent. {The poster formerly known as 87.81.230.195} 212.95.237.92 (talk) 14:34, 20 February 2015 (UTC)[reply]

Yes, it depends entirely on how the recycling center works. Here in Austin, Texas we have "single stream" recycling in some parts of the city - where anything recyclable goes into the green bin. But outside of the city, we're told to separate out metals from plastics, cardboard and paper into two separate bins. We're even told that some kinds of plastic must not be placed in the recycle bin where we're living now - but over on the other side of town, every kind of plastic was accepted.

So, you'll need to get information from your local trash collection agency. I bet they have a big pile of glossy brochures that they'd just love to send you giving you all the details...so call them up and ask. (You might not want to mention dead animals/humans though!)

In the specific example of the cat's collar - you may well be required to separate out the metal parts of the collar from the leather/plastic strap before you recycle it. Leather is organic and doesn't belong in the recycle bin at all. A nylon strap would be a pain to recycle too - burning it produces hydrogen cyanide gas - and composting it is virtually impossible too. Sorting it out from other recyclable plastics is hard - so even though it *can* be recycled into pellets for industrial use, the odds are very good that it won't be, so it'll be in landfill. These are the kinds of reason you need that glossy brochure that tells you what to do.

SteveBaker (talk) 15:56, 20 February 2015 (UTC)[reply]

Dead human body? What, are you in the mob? Unless you're tipping your waste collectors really well, I wouldn't stick them with the stiff. Even the kids in Stand by Me figured this one out; call the authorities. Snow -I take all complaints in the form of rap battles- 16:38, 20 February 2015 (UTC)[reply]

Clearly the dead kitten goes on the compost pile for the garden. It's not the best way to eat pussy, but scavengers can't be choosers. The dead human, not so much - you might catch mad human disease because the meat quality standards are nonexistent, especially in Britain. (I'd think the compost pile would kill it, but hell, nothing else that I'd think would kill prions does, so why should this be different) So I'd say go with Old Faithful... if you cared enough to kill him, don't you care enough to smash each little piece and watch it swirl away? That leaves that dang kitty collar per SteveBaker. Wnt (talk) 01:46, 22 February 2015 (UTC)[reply]

A query about cell phones and signals

This often happens and I am not sure why. If the question has been asked and answered, please direct me there. So here goes: I am sitting in an area (in this case a basement or lower level office). I get a phone call or text and reply. Two minutes later, when I try to call, text or check my email via my phone, I get no signal. I haven't moved more than a foot or two but suddenly can't get a signal. Then, later, the signal suddenly comes back. Again, I haven't moved! Why do I loose then regain then loose again the signal (especially if I have not moved to another location)? 216.223.72.182 (talk) 20:55, 19 February 2015 (UTC)[reply]

The wavelengths of the cell phone signals is only about 20 to 30 cm. The interference and changes in signal strength can easily change over 10 cm (a third of a foot). But not only that other things moving nearby like cars can change reflections of the signal to the basement. Also you may have been switched to s different frequency from the cell tower, which will have a different pattern of signal strengths. Graeme Bartlett (talk) 22:01, 19 February 2015 (UTC)[reply]

Thanks. I just realized, however, that I should have put this on the computer and tech desk! Sorry about that! 50.101.125.154 (talk) 04:22, 20 February 2015 (UTC)[reply]

I'm not sure I know enough about this to explain what's going on...but isn't there also an issue of having the cellphone needing to call up the tower and negotiate a suitable frequency to place the call on - raising the possibility that different frequencies have better range/power than others? I'm not sure about this one...but I bet someone here is! SteveBaker (talk) 18:41, 20 February 2015 (UTC)[reply]

5 ways organize information

Richard Saul Wurman means that there are five, and only five, ways to organize information: category, time, ~~relation~~, location, alphabet, and continuum (magnitude). Is there any other form to organize information besides these five?--Senteni (talk) 22:11, 19 February 2015 (UTC)[reply]

From my book titled Filing Systems by Edward A Cope: Organisation could be by who is dealing with it; in tray, out tray and a to-sign tray; organisation could be arbitrary or random, with a register or index to help you find it. Your category and relation are pretty broad and could be considered to cover all possible ways of organsing things anyway. This book calls your magnitude - "numerical", and this may include date or an amount of money. Alphabetical could be by subject or correspondent. It also talks about colour coding. One subset of location that may be important is "country". Information may have to be organised several ways at the one time, so it may need multiple indexes, or tags. You may also be interested in metadata. Graeme Bartlett (talk) 22:35, 19 February 2015 (UTC)[reply]

Um, isn't "category, time, relation, location, alphabet, and continuum (magnitude)" six ways? --70.49.169.244 (talk) 00:18, 20 February 2015 (UTC)[reply]

You are right, relation is not part of the list. Senteni (talk) 00:44, 20 February 2015 (UTC)[reply]

There's an entire research field of information organization. I'll second the suggestion for metadata, also perhaps markup languages, such as sgml, xml, json, etc. SemanticMantis (talk) 14:48, 20 February 2015 (UTC)[reply]

Wurman is wrong. You're using the perfect counter-example right now! Wikipedia is (mostly) organized as a maze of hyperlinks - these respect neither category, time, location, alphabet or magnitude. Yet they form a useful way to organize information by allowing you to navigate a semantic network. Admittedly we have the category system as an additional layer, and under the hood, the SQL database probably uses the title of the article as a 'key', implying an alphabetical ordering there...but Wiki's work perfectly well without a category layer, and the underlying implementation of the data storage system is irrelevant to the "organization" of the information. So perhaps "relation" is the right term here. That makes me think of a family tree as another counter-example that's both literally and figuratively based on a relationship network.

I think the ideas that Wurman is proposing here relate to organizing data in filing cabinets or in a rolodex or some other kind of antiquated system which was forced to be strictly linear in nature.

When the physical placement of a paper document is involved, it's hard to have anything other than a one-dimensional organization - which means that you have to find some means to take the sea of data that it contains and force that into a predictable, linear system...alphabetically, chronologically, etc - the "key" in database parlance. When you can only have one key, you have to pick some specific thing to sort with - the Dewey-decimal system in a library, for example. In the case of maps, we stretch that into two dimensions (latitude and longitude), but that gets difficult when the amount of information to be stored gets large...and some kind of linearization of that two dimensional space is forced upon you. You can certainly add more keys to the system - such as the card-file system of a traditional library has an index of author names and an index of document titles that contain "pointers" (in computing terms) into the dewey-decimal organized stacks. With an enormous amount of effort, one might index books by keyword or date of pubilication too...but this rapidly becomes impractical - and it still doesn't provide any way whatever to find (for example) all of the physics textbooks published between 1945 and 1955 in French that do not reference the works of Albert Einstein.

But with computer-based organizational systems, we're no longer limited by a one-dimensional system ordered by a single "key". We can have multiple keys - we can connect documents with each other in any way we like...and in multiple ways all at once. The way Google "indexes" the entire Internet by the number of times a document is referenced by other documents that seem relevent is an interesting example. You could never implement this in a physical system like a library because the purchase of a single new book could result in the entire library having to be re-shelved!

I think we're only just beginning to understand how to detach ourselves from Wurman-esque thinking and to start to organize documents in ways that are vastly more useful.

SteveBaker (talk) 16:50, 20 February 2015 (UTC)[reply]

Physical systems like libraries aren't as hard to index as you think:

1) Multiple indexes are quite possible, as in a card catalog indexed by title, author, and subject.

2) Adding one book does not require moving every book in the library, since they are smart enough to leave some open space on each shelf sector. So, at most, you would have to move all the books in that small space. And, unlike with computers, where moving 10 items one space over would require reading and writing 10 items, in a library you can just push and slide them all at once.

3) A library may occasionally need to reorganize, just as a database does. However, there are some additional options in a library, like adding new storage space in places other than the start or end. Or, this could be accomplished just like on a computer, with "memory fragmentation": "For the remainder of this section, please go to room 13B." StuRat (talk) 17:32, 20 February 2015 (UTC)[reply]

1) Sure, you can have multiple indices - but the cost of making them becomes extreme if (for example) you want to index by keywords extracted from the text. You could easily need to add each book to thousands of index cards - and for each index card to contain thousands of entries.

2) Normally, in (say) an alphabetical index, you'd be right - adding one new book requires pushing a couple of dozen books along the shelf - but the "pagerank" algorithm by which Google indexes the Internet isn't that simple. When you add a book with a decent biblography to your collection, it changes the pagerank of every book that it mentions - which could mean re-shelving all of those books into their new pageranked ordering. But it goes further - the "importance" of your new book in the subject area it covers determines the amount by which it alters the pagerank of the books it refers to...but that "importance" number derives in turn from its own pagerank. So having re-shelved all of the books that our new volume refers to, you now have to re-shelve all of the books that THEY refer to...and so on, recursively until no more reshelving is required. Even if you only resuffled index cards rather than physical books, it's an impossibly difficult problem in the physical world. The pagerank algorithm is truly amazingly useful - and yet it's simply not feasible without an entirely electronic indexing system.

3) You're right that it might need to do that - but the cost is extremely non-trivial because libraries store the books in a physically meaningful order to allow people to 'browse' a section more easily. In computing terms, we don't do that. The actual documents themselves are just dumped onto the hard drive of some server in whatever spare space is available - it's unlikely to move very much from that location unless it gets changed somehow. It's as if libraries just dumped their books anywhere on a convenient shelf and used the index card to tell people where to find it. That makes a huge difference. In a computer, you really don't have to move files around physically - all you're really moving is the records that are analogous to index cards. Reorganization of index cards is a LOT easier than reshelving books.

Once you abolish the need to store your records in any particular order whatever, and demand that every search go though an index of some kind - then make it very easy to create new stacks of index cards with different mappings of data to shelf-number - then make it much simpler to cross-correlate one index with another and another and so on - then entirely new ways to collate your data emerges - and although some hold-overs from libraries still exist (like the category/sub-category/sub-sub-category thing that Wikipedia uses, analogous to Dewey-decimal) - you can invent entirely new forms of organization, such as the maze-of-hyperlinks approach that is popularly used right here in Wikipedia.

As I said, we're only just beginning to scratch the surface of these creative indexing systems. Hyperlinks and PageRanks are just the first of those things to emerge that don't fit with Wurman's list of schemes...but more will surely be invented as humans come to live with this sea of data. I see things like 'pinterest' as another means for these connections to emerge.

SteveBaker (talk) 18:33, 20 February 2015 (UTC)[reply]

Physical records don't necessarily have to be stored in any particular order, either. For example, evidence records might just be stored in the order they are received, using indices to find the evidence based on victim's name, perps name (if known), crime, etc. StuRat (talk) 06:10, 21 February 2015 (UTC)[reply]

Information organization is distinct from information retrieval and Information architecture. Both Stu's and Steve's responses above conflate these concepts, and neither of them has cited any references. So Caveat emptor and all that.

I'll also add that Wurman has no formal training in library and information science as far as I can tell; he was trained as an architect, though he is credited with coining the phrase "information architecture."

If you want to learn about information organization from a reliable source, I recommend this book [6], "The Intellectual Foundation of Information Organization", by Elaine Svenonius, published by MIT press. It is widely used and recommended by the actual information scientists that I know. SemanticMantis (talk) 19:26, 20 February 2015 (UTC)[reply]

All I presented in my first response is the fact that there are at least two ways to organize information (pagerank and wiki-like maze-of-links) that cannot possibly fall into Wurman's list of (essentially) sort criteria. I don't think you can argue that both pagerank and wiki are organization schemes for information (that's certainly how they are used in two practical systems that all of us are very familiar with) or that they are somehow covered by Wurman's list. Since Wikipedia only requires references for facts that are not obvious, or which are likely to be disputed, I did not attempt to find any. My second response was merely a reply to StuRat's list of complaints. If you're going to be so prissy about demanding references - where is your reference for your claim that Wurman had no formal training in this field? Answering a very specific question with "Read this book" is utterly useless. We might as well answer every question with "Search the Internet for your answer" or "Go to a library and ask at their reference desk". If the answer to this question is indeed buried in that book, then either tell us what it says - or don't bother mentioning it. So before you dive in and start criticizing useful answers, you might look at your own posts and decide how helpful they are going to be to this OP. It's also arrogant to imply that you're the only one here who knows "actual information scientists" - at least two of whom are close friends and collaborators of mine.

FACT: PageRank and sea-of-links are schemes that work amazingly well and are heavily used.
FACT: Clearly neither of them fall into Wurmans' list of 5 ways to organize information.

Both facts are obvious to anyone who uses Google Search or Wikipedia (once they're pointed out) - hence no references are required.

If you wish to nit-pick that these are "retrieval" mechanisms and not organizations of the data itself, then Wurman is still missing one: "Random pile of stuff spread all over everywhere" which is what we have with the Internet and wikis. The need for any organization at all (in that fine technical sense) is obliterated once your ability to retrieve data efficiently from such a random pile becomes available. The old distinctions between how data is organized and how it's retrieved have blurred into insignificance outside of dead-tree-format databases - and the issue of "architecture" is just an implementation detail that Wurman was clearly not discussing - and which is increasingly about the architecture of the search mechanism rather than the information itself.

SteveBaker (talk) 16:13, 22 February 2015 (UTC)[reply]

I generally agree with your points, but I wouldn't characterize my response as a "list of complaints". You just pointed out some advantages of virtual file systems and I responded with some advantages of physical file systems. (For a few more, they aren't vulnerable to hackers, are still accessible without electricity, and last longer.) StuRat (talk) 16:27, 22 February 2015 (UTC)[reply]

Are Nobel prizes in science a Golden standard for quality?

Are Nobel committees more thorough than any other means? Senteni (talk) 00:41, 20 February 2015 (UTC)[reply]

The committee tends to wait long enough to make absolutely sure the award goes to work from at least twenty years ago - and if the person dies - tough luck. The accomplishments honoured are major, but not recent as a rule. Collect (talk) 00:48, 20 February 2015 (UTC)[reply]

That does not seem to be a real pattern. Plenty of people have received Nobel prizes for quite recent discoveries. Just looking at recent recipients of the Nobel Prize in Physics, there are e.g. George Smoot, who won the prize in 2006 for his ~~1998~~ 1992 discovery (14 years), Andre Geim in 2010 (after just 6 years), Adam Riess in 2011 (13 years), Theodor W. Hänsch in 2005 for work he did at the end of the 90s (~7 years) - Lindert (talk) 11:59, 20 February 2015 (UTC)[reply]

From 1998 to 2006 there are 8 years not 14. I wonder how you did the math. LOL. Noopolo (talk) 12:32, 20 February 2015 (UTC)[reply]

Thanks for spotting that, was a typo, should have been 1992. - Lindert (talk) 12:49, 20 February 2015 (UTC)[reply]

I'm not sure what "Golden standard for quality" is intended to mean in this context, nore "more thorough". The fact that, at most, only three scientists can share a particular award in a given year means that there will always be important work that isn't acknowledged with a Prize. One presumes that the Nobel Committee will engage in a certain amount of behind-the-scenes horse-trading and compromise, and will even make mistakes from time to time. It's usually fair to say that the science Prizes are awarded for highly-significant work that is certainly among the most important in its field; whether or not it represents the absolute 'best' is probably unanswerable and will depend on one's choice of criteria.

To take a popular (and safely historically-distant) example, Albert Einstein won the 1921 Prize in Physics for, nominally, his 1905 work on the photoelectric effect. While that was definitely good, important physics, it overlooks Einstein's other landmark 1905 work—including the Special Theory of Relativity. The list at Nobel Prize controversies – which is by no means exhaustive – gives a taste of some of the missed opportunities and controversial calls.

As well, a Nobel Prize (in the sciences) generally recognizes a particular piece of work or scientific contribution; it doesn't necessarily represent an endorsement of the scientist's overall body of work, and certainly shouldn't be read as an imprimatur of future infallibility (or even competence). While I've seen and interacted with a number of Nobel laureates who have been excellent scientists and delightful people, there are a number of notorious exceptions. Kary Mullis (credited with the discovery of PCR) has associated himself with the AIDS denialist movement. Luc Montagnier (co-discoverer of HIV) got into homeopathy and the idea that viruses leave electromagnetic imprints in highly diluted water. Brian Josephson (prediction of quantum tunneling "Josephson effect") is into psychics, ESP, and cold fusion. TenOfAllTrades(talk) 13:24, 20 February 2015 (UTC)[reply]

Not to forget about James Watson, who is shunned by academia. Noopolo (talk) 14:09, 20 February 2015 (UTC)[reply]

And to add to TenOfAllTrades comprehensive reply: at least a couple of pieces of work awarded the Nobel Prize in Physiology or Medicine have themselves been challenged as wrong or harmful. Namely the 1926 award to Johannes Andreas Grib Fibiger (see this retrospective analysis), and the 1949 award to Egas Moniz (see this and this for some views). Abecedare (talk) 19:23, 20 February 2015 (UTC)[reply]

The noble prize is generally awarded for achievements that have already been widely recognised. It is more important that they are comparing the levels of achievement and importance rather than analysing the actual achievements themselves. Often identifying a handful of originators is essentially impossible, since scientific achievements are generally steps built up from the works of others and not completely out of the blue. Second Quantization (talk) 12:56, 22 February 2015 (UTC)[reply]

Per act transmission of HIV/AIDS

what's is the per act transmission rate of HIV for a man performing cunnlingus, both in general and if the man/woman whom he's giving it to has HIV? — Preceding unsigned comment added by Bubbly water31 (talk • contribs) 23:17, 19 February 2015 (UTC)[reply]

Low per the CDC. [7] --Modocc (talk) 01:02, 20 February 2015 (UTC)[reply]

Just a quick note: cunnilingus can only be performed on female genitalia. Fellatio is the corresponding act. Dismas|^(talk) 11:18, 20 February 2015 (UTC)[reply]