Wikipedia:Reference desk/Archives/Science/2010 March 3

= March 3 =

salt peter
does eating potassium nitrate reduce testosterone? ( pilgrims did it to lower the sex drive ) how does it work —Preceding unsigned comment added by 67.246.254.35 (talk) 00:14, 3 March 2010 (UTC)


 * According to our article Potassium nitrate, "saltpetre is thought to decrease sex drive, but there is no scientific evidence to support that the substance causes such an effect". And the reference for that is Jones, Richard E.; Kristin H. López (2006). Human Reproductive Biology, Third Edition. Elsevier/Academic Press. p. 226. ISBN 0120884658, 9780120884650. --Tagishsimon (talk) 00:29, 3 March 2010 (UTC)


 * So, the myth that it causes impotence is just a big boner (def. 3) ? StuRat (talk) 18:30, 3 March 2010 (UTC)


 * Batman agrees. 86.177.121.239 (talk) 20:37, 3 March 2010 (UTC)


 * I had a teacher in school who hopefully was unaware of the more recent definition, and returned from the copy room with both sides of the test copied over the top of each other on the same side, only to say "I just pulled a giant boner". We never quite thought of that teacher the same way again. StuRat (talk) 19:18, 4 March 2010 (UTC)

brine shrimps
How long do brine shrimps live in enclosed containers? can they live longer if they break open the container and put them in a fish tank?? —Preceding unsigned comment added by Delvenore (talk • contribs) 02:10, 3 March 2010 (UTC)


 * Do you mean: “how long will their dormant cysts remain viable in a closed container?” The answer to this is easy: nobody is sure! anhydrobiotic animals are extreamy tollerant to harsh conditions when in this state. See: NASA article A Pothole in the Road of Life By: Leslie Mullen. This means that they will survive many years longer in this state than in a fish tank (year at most)-especially if the fish are hungry. --Aspro (talk) 14:56, 3 March 2010 (UTC)

Why would anyone use a pH meter instead of an indicator for acid-base titrations?
I've only used an indicator for acid-base titrations but I heard that some people use a pH meter instead. I don't really see much difference other than that indicator only works in certain pH range and pH indicator works in all pH. —Preceding unsigned comment added by 70.68.120.162 (talk) 03:57, 3 March 2010 (UTC)


 * A pH meter gives you a more precise value for your solution's acidity, which is why we use it whenever we have to make an acid-base buffer or otherwise adjust a solution's pH within a narrow range. Clear skies to you 24.23.197.43 (talk) 05:16, 3 March 2010 (UTC)

Rate of freezing vs temperature
Which would you say would freeze the fastest: Boiling hot water, room-temperature water, cold water? Explain. 198.188.150.134 (talk) 08:19, 3 March 2010 (UTC)
 * Welcome to . Your question appears to be a homework question. I apologize if this is a misevaluation, but it is our policy here to not do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn how to solve such problems. Please attempt to solve the problem yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. A hint, though: Mpemba effect -- Aeluwas (talk) 08:53, 3 March 2010 (UTC)
 * Welcome to . Your question appears to be a homework question. I apologize if this is a misevaluation, but it is our policy here to not do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn how to solve such problems. Please attempt to solve the problem yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. A hint, though: Mpemba effect -- Aeluwas (talk) 08:53, 3 March 2010 (UTC)


 * Nope, this is not a homework question! Just because I put the word "Explain" doesn't imply that at all. I was merely curious ever since I've read about the mpemba effect. I know hot water freezes quicker than cold water but what about room-temperature water vs cold water? Which freezes faster then? 198.188.150.134 (talk) 08:57, 3 March 2010 (UTC)


 * Why not try it and see for yourself? I'm sure it will be an interesting experiment. (A word of caution: Putting boiling water in the freezer may cause the container to shatter due to thermal shock.) 24.23.197.43 (talk) 09:28, 3 March 2010 (UTC)


 * There has to be some clarification and some care taken in defining our terms here. The Mpemba effect isn't magic.  Boiling water has to become cold before it can freeze - so what this experiment says is that there are two kinds of "cold water" - the kind that has just come out of the cold tap of your sink - and the kind that was boiled and then cooled down to that same temperature.  But we know that one container of chemically pure water at a specific, uniform temperature is no different than any other identical container of pure water at the same uniform temperature then the two must freeze at the same rate.  Since the boiling water first has to reduce in temperature and then freeze - it can't possibly freeze faster than cold water if we control all of the bizarre side-effects relating to the nature of the container, the stuff that's dissolved in the water, evaporation during the experiment and inhomgeneities in the temperature.


 * But the Mpemba effect does work in the kinds of uncontrolled situations that come up in simple experiments. It clearly shows that in an uncontrolled situation, the boiling water freezes faster (at least for some definitions of "freezes").  So this can't strictly be about the temperature of pure water in an idealized container - it's about some other aspect of the situation.  Given that, there will undoubtedly be some variations on the experiment that take more care over the purity of the water, the container it sits in, etc that will make the results come out the way common sense would make you expect them to.


 * Our article on the effect lists several causes that have been considered but all of them are about the nature of the container or some other aspect of the way in which the experiment is conducted. For example, it is far from clear whether boiling water will freeze sooner than cold water if both are stirred continually - or if the boiled water is kept in a gas-tight container that would prevent water from escaping - thereby reducing the overall volume that remains to be frozen.  It's not clear whether the boiled water does indeed completely freeze before the cold water - it's suspected that a thin crust of ice may form on the top of the boiled water but the liquid beneath take much longer to freeze than the initially cold water.  The Mpemba effect is therefore not so much to do with the properties of water - but more to do with the definition of the results and the way in which the experiment is conducted.


 * We know that when careful experiments are done, the anomalous results vanish and the system behaves as common sense says it should. However, having said that, we don't have a single, proven answer for why this happens in the uncontrolled case - and it would be nice if more studies could be done so that we can put this one to bed with a clear, logical explanation.


 * The bottom line here is that if you want to make some ice-cubes fast, you might well get them to freeze faster by boiling the water first...but on the other hand, maybe you won't - a lot will depend on the water quality and the shape and material of your ice-cube tray.


 * But you should not take away from that the idea that the laws of thermodynamics need to be repealed or that water has some kind of magical memory effect (such as, for example, the homeopathy nut-jobs would have us believe). It's simply that the physics and chemistry of the general situation are a lot more complex than the simple statement "hot water freezes faster than cold" implies.  The Mpemba effect should probably state something like "Some mixture of hot water with other dissolved ingredients in an open container where convection currents are not inhibited will first produce some freezing before a similar mixture that starts off cold completely freezes." - which is a much less strong statement (and frankly, one that would not have surprised anyone).  SteveBaker (talk) 13:14, 3 March 2010 (UTC)


 * Aristotle would have explained the Mpemba effect as a clear case of Antiperistasis and left it at that. This video demonstration was put on YouTube less than a month ago. Cuddlyable3 (talk) 16:49, 3 March 2010 (UTC)

Night Purge Ventilation
I was wondering if this was an effective method of cooling a building in a relatively mild climate. I can't find much reliable information. I think it relies on venting a building during the night when the air is naturally cooler and having the air cross a thermal mass, which will store the 'coolness' (release heat into air) and then cool the building during the day when it it occupied and warmer. Thanks. —Preceding unsigned comment added by 69.181.156.221 (talk) 08:22, 3 March 2010 (UTC)


 * From what I understand of your description of this method, it may amount to something as simple as leaving the windows open at night. Yeah, I normally do that (I live down south), and I tell you, it really works, 'specially on cool autumn nights (not so much in midsummer, unfortunately...) 24.23.197.43 (talk) 09:39, 3 March 2010 (UTC)


 * See passive cooling. 75.41.110.200 (talk) 14:20, 3 March 2010 (UTC)


 * I don't think simply leaving windows open is all that effective, for the following reasons:


 * 1) The thermal capacity of air is quite low. This means that most of the heat stored in a building is in the floors, walls, furniture, etc., not just in the air.  Therefore, you don't just need to exchange the air once, but several times, allowing some of the heat from the floors, walls, and furniture to bleed off into the air each time.


 * 2) Strong winds are required to force the air out of the building. Unless you have consistently strong winds in the proper orientation and a clear path through the building that exchanges all the air, you need to use intake and exhaust fans. Fans can still use far less electricity than A/C, however.


 * 3) Humidity and rain can be an issue. Rain is easier to deal with, as an overhang can prevent rain from spraying in.  Humidity, on the other hand, can be a real problem.  Even if you lower the temp of the building, raising the humidity can make it even more uncomfortable, and more expensive to remedy with A/C.  Therefore, exchanging air only makes sense where and when there's dry air outside.  A desert would be a good choice, for example, with cool, dry air at night.


 * 4) Papers can be blown around. This can be fixed, of course, if people know to secure all papers before they leave at night.


 * 5) Windows don't open in many modern office buildings. This is a serious limitation when it comes to being environmentally friendly, leading to using A/C inside even when it's nice and cool outside, due to solar heating of the building and heat generated from the people and machinery inside.  Screens are also required to keep insects, bats and birds out, and most office buildings don't have those, either.


 * 6) Overcompensation can be an issue. To keep it cool all day long, you need to make it quite cold in the morning, perhaps so cold people would need to wear jackets. StuRat (talk) 14:50, 3 March 2010 (UTC)


 * Original research here: it works just fine in a small building in a semi-desert climate. Rain is rare, and the roof overhang common in residental structures takes care of that when it does happen.  Strong winds are not required: you can exchange ventilation area for air speed, so (for example) a single large sliding door, a few windows, and a wind speed of one mile per hour can exchange the air in my apartment once every three minutes. --Carnildo (talk) 01:48, 4 March 2010 (UTC)


 * I'm rather skeptical of the 3 minute claim. How have you measured it ?  Here's a test you can do:  Let an egg rot in a sealed container (like a mason jar), then expose it to the air in the apartment.  Open the windows and see if the stink completely disappears in 3 minutes. StuRat (talk) 15:26, 4 March 2010 (UTC)


 * I've done something similar: cook something with a strong odor, then see how fast the smell goes away after I put away the leftovers. The kitchen circulation isn't as good as the rest of the apartment, but it's still gone within ten minutes. --Carnildo (talk) 01:23, 5 March 2010 (UTC)

general principles of pharmacy technician practice
What are the relationship between the pharmacy technician and other health workers in an hospital setting. —Preceding unsigned comment added by Enipez (talk • contribs) 08:57, 3 March 2010 (UTC)


 * Um, they ask him for drugs, and he gives them what they asked for ? I have a feeling this a homework Q, so look through the book and regurgitate whatever they say about it. StuRat (talk) 22:21, 3 March 2010 (UTC)

Why bring eggs to room temperature?
Cookbooks always tell you to bring eggs to room temperature before using them in a recipe, such as for cake or cookies, but they never tell you why. (I know that people in many countries don't refrigerate eggs in the first place, so this question really only applies to those who do usually refrigerate them.) What difference does it make to my cake or cookie recipe whether the eggs are cold or not when I beat the eggs in? The batter/dough stabilizes to approximately room temperature by the time it's all mixed ready for baking anyway, doesn't it? +Angr 10:46, 3 March 2010 (UTC)


 * I'm not really sure, but it could have something to do with them being more viscous below room temperature (and therefore more resistant to being mixed into the dough). Clear skies to you 24.23.197.43 (talk) 11:02, 3 March 2010 (UTC)


 * Yes, that's the idea. Colder eggs will tend to clump together and form lumps in the batter.  It's not a huge difference, though, and you could probably just beat the batter a bit more to get the lumps out, if you don't have time to wait for eggs to warm to room temp. StuRat (talk) 14:31, 3 March 2010 (UTC)


 * (ec)There are a couple of different reasons, depending on the application. For example, in an omelet the eggs should be warm because the short(er) thermal trip from raw to cooked gives you a shorter cook time and therefore a more tender end product. In other cases, such as where the egg (specifically the yolk) is being added to create an emulsion the warmer temperature helps reduce viscosity and allow for more thorough mixing (and therefore a more even texture), as 24.23 says above. Matt Deres (talk) 14:40, 3 March 2010 (UTC)


 * Perhaps also for the same reason recipes often call for unsalted butter only to later add salt: so that everyone's starting on the same page, whether they refrigerate their eggs or not. --Sean 16:43, 3 March 2010 (UTC)


 * Page 208 of Shirley Corriher's Bakewise says that room-temperature eggs beat faster and separate more easily. Similarly, page 122 cites a source who says that cold eggs give less volume.  -- Coneslayer (talk) 16:56, 3 March 2010 (UTC)

Sexuality of Hedgehogs
I have three questions:


 * 1) Are there any recorded cases of gay / lesbian hedgehogs?
 * 2) Can and do hedgehogs masturbate?
 * 3) Do hedgehogs experience orgasms?  —Preceding unsigned comment added by Delvenore (talk • contribs) 11:03, 3 March 2010 (UTC)
 * I refer you to "The Hedgehog Song".http://www.youtube.com/watch?v=wmPeX6syPPY (Warning: lyrics NSFW) --TammyMoet (talk) 13:00, 3 March 2010 (UTC)


 * The Wikipedia article Hedgehog has a section about the animal's reproduction that mentions that their physical difficulty of mating has a counterpart in human psychology. Cuddlyable3 (talk) 17:22, 3 March 2010 (UTC)


 * Not exactly Cuddlyable3. The article Hedgehog explains why it is not a problem for a hedgehog to have a sexual encounter with a female hedgehog.


 * From the article: "The hedgehog's dilemma is based upon the apparent danger of a male hedgehog being injured from a spine while mating with a female hedgehog. However, this is not a problem for hedgehogs as the male's penis is very near the center of its abdomen (often mistaken for a belly button) and the female has the ability to curl her tail upward to the point that her vulva protrudes behind the rest of her body. As such, the male doesn't have to get completely on top of the female when mating."--Quest09 (talk) 18:16, 5 March 2010 (UTC)--Quest09 (talk) 18:16, 5 March 2010 (UTC)

inhaling
I learned that when smoking marijuana it is more effective to "hold it in" for as long as possible after inhaling to maximize the amount of THC taken in. Is this tactic effective? —Preceding unsigned comment added by ShadowFire101001 (talk • contribs) 11:17, 3 March 2010 (UTC)


 * Probably, but it will also maximize the amount of tar that ends up in your lungs. Eating "special brownies" or taking THC capsules would be far more effective at getting the good stuff without the bad. StuRat (talk) 14:19, 3 March 2010 (UTC)


 * In USA Marihuana Tax Act of 1937 criminalised sale and use of Marihuana which is a preparation of the Cannabis plant. It is a Class B controlled drug in the UK. Smoking of cannabis is the most harmful method of consumption and brings the user into close or actual involovement with Drug abuse, illegality and drug peddlers.THC is only one of the active chemicals that a marihuana smoker ingests. Some research suggests THC may have some medicinal value besides its toxicity and negative mental effects. It is irresponsible to encourage anyone to self-medicate with THC derived by smoking, as might be inferred from StuRat's expression "the good stuff". Cuddlyable3 (talk) 14:52, 3 March 2010 (UTC)


 * Who is asking anyone to self-medicate? Is it more irresponsible than telling someone how to mix a good drink? What if the original poster is in a jurisdiction where marijuana is legal? Just pretend the poster asked: "Is the transference of THC to the bloodstream maximized by holding in the inhalation of marijuana smoke, or is that a myth?" A perfectly good science question. --Mr.98 (talk) 15:28, 3 March 2010 (UTC)


 * That's 3 supplementary questions. Answers in order: 1) Nobody asked. StuRat encouraged, see above. 2) Yes. 3) Legality does not make an action harmless. No, we don't rewrite an OP's question. Cuddlyable3 (talk) 17:04, 3 March 2010 (UTC)


 * 1) No, I didn't.


 * 2) Wrong. Alcohol is far more harmful, as numerous studies and statistics have shown.


 * 3) It's absolutely true that being legal doesn't make something harmless, as in the cases of alcohol and tobacco. Conversely, being illegal, ostensibly for health reasons, in no way means that the substance is actually harmful.  Unfortunately, lobbying by powerful interests has far more impact of what is legal or criminalized than science ever will. StuRat (talk) 17:44, 3 March 2010 (UTC)


 * So... let me get the right: we shouldn't tell someone about marijuana, because they might continue doing exactly what they already said they are doing. StuRat (and my) answer is actually one that encourages one to do the less harmful practice here—emphasizing the lung damage that comes from such activities (and such myths). Whether you think people should abstain from consuming THC in any form or not seems irrelevant here. Anyway, no one is encouraging anyone to do anything (other than not believe harmful myths!). In any case, this is a topic that has been researched by real-deal scientists, so I think that by itself should give us some clue that it's not an illegitimate question for the Science ref desk. (In any case, the post doesn't say that the poster actually smokes—just that they "learned" this myth from someone.) --Mr.98 (talk) 17:51, 3 March 2010 (UTC)


 * 1) StuRat identified THC as "good stuff" and thereby endorses ingesting THC with no warning or qualification. That is not NPOV and a drug peddler's pitch would sound the same.
 * 2) Good drinks are not necessarily alcohol drinks. StuRat's argument is to introduce a strawman because mixing alcohol drinks has nothing to do with self-medication with THC.
 * 3) I answered the question "What if....legal" with a truth that StuRat agrees.
 * Cannabis has been judged by many to be so harmful that it must be controlled by laws. It is okay to debate the medical evidence for those judgements. But StuRat cannot dismiss such a weight of evidence and legal opinion merely by claiming that it "in no way means" anything. The rant about alcohol, tobacco and alleged "powerful interests" is OT. StuRat claims science will always be impotent in guiding legislation but that prediction is crystal ball gazing. Cuddlyable3 (talk) 03:04, 4 March 2010 (UTC)


 * 1) There's plenty of medical evidence or the benefits of THC:, but that really isn't relevant the the Q, which was how to increase absorption of THC. Whether they should is not the Q (and would be a request for medical advice).


 * 2) You know very well that the phrase "drinks" was used in this context to mean alcoholic drinks. Pretending otherwise is disingenuous.


 * Science should never be based on useless "legal opinion". When we do so we get really bad science, like Galileo being forced to say that the Sun revolves around the Earth, in order to comply with the law.  I don't know what "OT" means, did you mean OR (Original Research) or OTT (Over The Top) ?  The La Guardia Committee was an early scientific inquiry which determined that marijuana was not as harmful as politicians, specifically Harry J. Anslinger, claimed in their justification for criminalization. StuRat (talk) 15:05, 4 March 2010 (UTC)


 * 1) StuRat you use the qualifier plenty to tell us that your opinion is that there is enough evidence to justify what you endorse. I say your endorsement of THC as "good stuff" is reckless and opinionated. Your alleged plentiful evidence hasn't overwhelmed the medical world yet.
 * 2) Please use any English dictionary to help you comprehend the word "drinks". It is a word not a phrase. If you mean "alcoholic drinks", "carbonated drinks", "hot drinks", "cold drinks" or any other category of drinks then make the effort to write what you mean. Contrary to your false claim, I did not know that you meant "alcoholic" drinks because I don't read your mind.
 * OT stands for Off Topic. If you now imagine yourself as a champion of good science like Galileo Galilei and living in a world where legalities are mere useless opinions then you have detached yourself from reality as well as social responsibility. Cuddlyable3 (talk) 21:54, 4 March 2010 (UTC)


 * 1) Since you are the one claiming THC does more harm than good, it's your responsibility to back that claim up with evidence, not mine.


 * 2) You are either unaware that the meaning of words is dependent upon the context in which they are used, which would mean you suffer from a learning disability, or are just pretending to not know what the word meant in this context, to be difficult. Clearly (to everyone but you), the word "drinks", in the context of a discussion of another drug, THC, refers to drinks containing a drug, namely, alcohol.  And that would be ethyl alcohol, just in case you are unable to determine this from the context, due to your learning disability .  If you are really that incompetent to not understand what words mean in context, then you shouldn't be (trying to) contribute here.  And you also seem to think that I used the word initially.  I didn't, Mr. 98 did.


 * If you imagine that legal opinions carry any weight in the scientific world, it's you which have detached yourself from reality. More recent cases involve the teaching of evolution.  But, I guarantee that scientists won't change their stance on evolution based of whether the law decides it can be taught or not. StuRat (talk) 23:24, 4 March 2010 (UTC)


 * 1) False premise. I have made no such claim.
 * 2) StuRat's response violates WP:NPA. Otherwise StuRat's retort is a collection of fallacies, still defending the notion that the qualifier "alcohol" must be assumed where it does not exist because that would be part of Mr. 98's pro-marihuana smoking rhetoric.
 * StuRat must be informed that:
 * The Ref Desk is not the place for pursuing an opportunistic debate that is OT to the OP.
 * StuRat may argue about marihuana in an apropriate forum. StuRat would be wise to avoid hand-waving claims of having plenty of evidence, denial of the function of Law in civilised society, personal insults, and ridiculous parallels to Galileo and Evolution.
 * I have identified in red the abuse by StuRat to help intervention stop this. Cuddlyable3 (talk) 13:51, 5 March 2010 (UTC)


 * As for answering the question... what you're asking about, in medical terms, is whether "breathhold duration" affects the absorption of THC or not. As far as I can tell from a few articles on Google Scholar, the answer seems to be, "probably not." On the contrast, they do seem to be associated (as StuRat said) with higher levels of tar, which is bad. My skimming of the literature seems to imply that volume of smoke matters (which makes sense), but breathhold duration does not. (This page has a lot of references to studies on it, along with summaries of their conclusions.) So, without wanting to give any kind of medical advice, I would tend to think that a marijuana smoker would be better off not holding their breath for a long time, as it does not seem to increase THC absorption, and does more lung harm that way. --Mr.98 (talk) 15:37, 3 March 2010 (UTC)


 * Bill didn't inhale. (video) Cuddlyable3 (talk) 17:08, 3 March 2010 (UTC)


 * And, based on some of W's statements, I'd have to say he's "still waiting to exhale". StuRat (talk) 22:12, 3 March 2010 (UTC)


 * No, you don't have to say anything. But anything you do say will be used to judge you. Cuddlyable3 (talk) 03:04, 4 March 2010 (UTC)

String theory
How many degrees of freedom does a string have ie the largest possible set of commuting observables? What are these degrees of freedom? 174.112.66.226 (talk) 13:13, 3 March 2010 (UTC)


 * I seem to recall that there are many variants on string theory, some of which have closed strings (loops) and others of which have open strings. I suspect that this would result in a variable number of degrees of freedom. StuRat (talk) 16:42, 3 March 2010 (UTC)


 * Yes, I was aware of this. In fact, many string theories have both closed and open strings. 174.112.66.226 (talk) 17:32, 3 March 2010 (UTC)


 * Would the number of degrees of freedom correspond with the number of dimensions, in each version of string theory ? StuRat (talk) 18:21, 3 March 2010 (UTC)


 * I doubt it; there should be more degrees of freedom than dimensions, since a string is not a point particle; it has substructure. I want to asking what degrees of freedom this substructure has, since I was already aware of the position/momentum/angular momentum degrees. 74.14.111.8 (talk) 21:52, 3 March 2010 (UTC)


 * But aren't there extra hidden dimensions associated with that internal structure ? I don't believe that string theory limits itself to the familiar 3 linear and one temporal dimension. StuRat (talk) 22:07, 3 March 2010 (UTC)


 * There are extra spatial degrees of freedom, but, even if all dimensions are treated as spatial rather than internal, there are still more degrees of freedom than a point particle in 10/11/26 dimensions would have. 70.27.196.12 (talk) 01:30, 4 March 2010 (UTC)

"Dimensions" in string theory is really code for the number of independent degrees of freedom, so there are 10 or 11 or 26 depending on the assumptions of the theory. The classical picture of a physical string with substructure that might be arbitrarily positioned really isn't helpful since the eigenstates of a quantum string are only allowed to be pure vibrations with an integer number of waves. Dragons flight (talk) 02:08, 4 March 2010 (UTC)


 * Thank you for your answer. Just to make sure I fully understand you, does that mean that a single string without interactions would behave identically to a point particle in however many dimensions with an extra quantum number representing the number of waves? Wouldn't a string's vibrations require a plane of polarization? 70.27.196.12 (talk) 03:24, 4 March 2010 (UTC)


 * Your question doesn't really make sense. If you imagine a physical string tied to a post, then you might shake it right-left and up-down.  Those would be two dimensions.  In string theory, the number of dimensions specifies the number of "ways" in which one can "shake" the string.  For each dimension there would exist an integer specifying the number of waves in that direction (subject to various technical constraints).  Once you specify all 10 (or 11 or 26) integers you have completely specified the properties of some possible particle.  How those integers map onto conventional quantum numbers is not necessarily trivial however.  Dragons flight (talk) 04:28, 4 March 2010 (UTC)


 * Oh, I get it now. 99.237.180.215 (talk) 17:07, 4 March 2010 (UTC)

mass/weight question
Does a Pokemon retain the same mass/weight when inside its Pokeball —Preceding unsigned comment added by Teltala (talk • contribs) 13:30, 3 March 2010 (UTC)


 * According to Gameplay of Pokémon, the Pokémon is converted into energy when put into the Poké Ball. You may like to read mass–energy equivalence to see what happens when mass is "converted" to energy. +Angr 13:53, 3 March 2010 (UTC)


 * Also, I'd ask a fictional Q like this at the Entertainment Desk, not here. StuRat (talk) 14:16, 3 March 2010 (UTC)

Science for Dummies website
Any suggestions for websites for the scientifically challenged? What I would like to do is read about a certain topic then do my own research on Wiki. BTW, I am a fan of Neil deGrasse Tyson's approach to teaching astronomy, for instance. --Reticuli88 (talk) 13:47, 3 March 2010 (UTC)


 * Simple Wikipedia. Cuddlyable3 (talk) 14:21, 3 March 2010 (UTC)


 * Well, there's the PBS website. You might like the Discovery Channel, too. Also, you might want to get the book Cosmos by Carl Sagan or rent the series on DVD. StuRat (talk) 14:23, 3 March 2010 (UTC)

Thank you,thank you Cuddlyable! Did not know this existed! Thank you!--Reticuli88 (talk) 14:25, 3 March 2010 (UTC)


 * Simple Wikipedia is written in a simplified form of English. It uses a restricted set of words in its articles, but that doesn't mean it makes science topics easier to understand for non-scientists. I still find simple:Quantum mechanics very difficult to understand, for example. +Angr 16:13, 3 March 2010 (UTC)


 * It may be an unpleasant truth that some topics will be dificult to wrap your mind around regardless of how well it is explained.


 * There are two types of simplification, those which still present the full material, but in an easier to understand fashion, and those which actually present a simplified (and thus less technically accurate) model. For example, subatomic physics gets quite messy when electrons are thought of as a quantum probability function, but is far easier to picture when they are thought of as little balls orbiting the atomic nucleus in circular rings.  Depending on the audience, this simplification may be entirely sufficient, as it is for most chemists, for example. StuRat (talk) 17:31, 3 March 2010 (UTC)


 * See lie-to-children for more on this kind of simplification. -- Coneslayer (talk) 19:06, 3 March 2010 (UTC)


 * There are many adults, even scientists, which use simplified models for the majority of their work, such as the atomic model used by most people in the chemistry industry. For another example, Newtonian physics is used for almost all real-world calculations, as time-dilation and other relativistic effects simply aren't significant when, say, designing a car bumper. StuRat (talk) 19:31, 3 March 2010 (UTC)


 * The article I linked to says The word "children" should not be taken literally and Such statements are not usually intended as deceptions, and may, in fact, be true to a first approximation or within certain contexts. (However, I would also point out that there's a difference between using a simplification in your work, and teaching that simplification as "the truth."  Lies-to-children is specifically about pedagogy, not simplification/approximation as strategy in problem solving.)  -- Coneslayer (talk) 19:51, 3 March 2010 (UTC)


 * Yes, and that's why it's not particularly relevant to what I was talking about. StuRat (talk) 20:02, 3 March 2010 (UTC)


 * Depending on the type of science question How Stuff Works might be OK. APL (talk) 16:23, 3 March 2010 (UTC)

Turbulent gas
I have a gas stove. When I turn it on low, it makes a steady hissing sound and each of the flame tips stays blue and at the same height. When I turn it up high, it makes a sound more like a windy day, and the flame tips flicker in and out and up and down with flecks of orange mixed in with the blue. I assume that the first case is laminar flow and the second case is turbulent flow. Is this correct ? Also, does turbulent flow lead to less complete combustion, and thus more unburnt gas and carbon monoxide released into the air ? StuRat (talk) 15:27, 3 March 2010 (UTC)


 * you should probably clean the burners - you shouldn't get turbulent flow like that, even under high pressure. It's difficult to say whether you are getting less complete combustion or more diffuse combustion - both would produce orange flame because the combusting elements are less concentrated.  -- Ludwigs 2  16:08, 3 March 2010 (UTC)


 * Have a look at the illustration of flames at the article Bunsen burner. Cuddlyable3 (talk) 20:58, 3 March 2010 (UTC)


 * That seems to imply that the orange flame is a sign of insufficient air for the gas volume, and thus incomplete combustion. StuRat (talk) 21:19, 3 March 2010 (UTC)

Traffic
Is it legal to travel down a road in reverse, as long as your following the direction of the traffic? —Preceding unsigned comment added by Dendalonger (talk • contribs) 16:03, 3 March 2010 (UTC)


 * no. -- Ludwigs 2  16:09, 3 March 2010 (UTC)


 * Specific laws will apply in different jurisdictions. In the UK, if I recall correctly, the Highway Code says that one may reverse only as long as is necessary for the manoeuvre one is doing (turning, parking, backing out of a space or away from an obstacle); I don't think it specifies an actual distance. -- Finlay McWalter • Talk 16:11, 3 March 2010 (UTC)
 * Or there's the cover-all driving without due care and attention, a bucket designed to scoop up the many stupid things one can do with a car. FMcW is right: section 203 of the Highway Code says "You MUST NOT reverse your vehicle further than necessary."--Tagishsimon (talk) 16:12, 3 March 2010 (UTC)


 * every jurisdiction I know of has generalized laws against driving in a fashion that endangers other people. Trying to drive a car in reverse under normal traffic conditions will inevitably constitute endangerment - difficult body posture, poor visibility, poor steering control, and etc all add up to lessened control over the vehicle.  **  -- Ludwigs 2  16:19, 3 March 2010 (UTC)
 * ** = deleted part of post. Cuddlyable3 (talk) 16:53, 3 March 2010 (UTC)
 * On single-track roads it is legal and often necessary to reverse for a hundred yards or more to find a place wide enough when meeting a vehicle travelling in the opposite direction. Those who regularly drive on such roads become adept at reversing at speed.  Such roads are perhaps rare in the USA.    D b f i r s   02:07, 4 March 2010 (UTC)
 * Most such roads (in the UK, at least) have regular passing points, so 100 yards would be unusual. If one (or both) of the vehicles is particularly wide (I was once on a bus that met a horse-box on a narrow road) then much more reversing can be required. This is all consistent with what has already been said - you can reverse for as far as it necessary. Sometimes it is necessary to reverse 100 yards, so you are allowed to do so. --Tango (talk) 04:53, 4 March 2010 (UTC)


 * They aren't rare in the US, just rarely traveled. Most of them are logging roads or other limited-use roads. --Carnildo (talk) 01:32, 5 March 2010 (UTC)

Nothing but the tooth
I hear a lot about how acidic drinks, like soda pop, dissolve the teeth, leading to cavities. How about alkaline drinks ? Are there any, and are they bad for the teeth ? StuRat (talk) 16:45, 3 March 2010 (UTC)


 * Unless you happen to drink them both at the same time (and in the same proportion, such that they balance each other out), conventional wisdom tells us that alkaline (caustic) liquids can be just as damaging, in similar ways, as acidic liquids. As far as their existence, there certainly isn't anything that rivals the prevalence of carbonation/phosphate additive in modern drinks.  Probably thanks to the pretty bad reaction they have with the taste buds.--144.191.148.3 (talk) 17:00, 3 March 2010 (UTC)


 * There just aren't many alkali foods at all. Alkali foods have a very bitter taste; there are a few foods which are processed with alkali (like Dutch process chocolate and Hominy).  However, in these foods, the alkali is often washed away, and the food itself is used in applications that returns them to a more neutral or slightly acidic state.  The only food I can think of which is eaten in a strongly alkali state is lutefisk, the taste of which can most charitably be described as "soapy".  Generally speaking, however, nearly all foods lie on the lower side of 7 on the pH scale.  -- Jayron  32  17:07, 3 March 2010 (UTC)

So, basically, there are no alkaline foods or drinks. I don't think that's a lye, but what about sour balls ? StuRat (talk) 17:22, 3 March 2010 (UTC)
 * Sour tastes are generally associated with acid not alkali. Googlemeister (talk) 17:35, 3 March 2010 (UTC)
 * ... Sour flavor, when added artificially, is often from citric acid or ascorbic acid. The kind of sour that you experience when tasting alkalinity is a less desirable one, to say the least. --144.191.148.3 (talk) 17:46, 3 March 2010 (UTC)

Baking soda is alkaline, right, and people use it to clean their teeth, right? Looie496 (talk) 21:40, 3 March 2010 (UTC)


 * Indeed, but you don't generally ingest a dentifrice; you spit it out. Likewise, while the alkali baking soda is often used as part of cooking, the end product which you actually eat, like a bread or a cake, is not actually alkali, it is usually very close to neutral or slightly acidic.  -- Jayron  32  21:50, 3 March 2010 (UTC)


 * Tooth structure demineralizes at an average pH of 5.5 (I say average because enamel, dentin and cementum are of different compositions and relative mineralization and will dissolve at different pHs). The general formula for hydroxyapatite (tooth mineral) is [Ca5(OH)(PO3)]2 -- two molecules in a united pair.  An acidic environment will draw the hydroxyl group out of the hydroxyapatite, causing it to dissociate.  That's why F- is provided to protect teeth from demineralization -- despite what our article on Hydrofluoric acid states, dental text books promote the idea that HF moves towards ionization with such power that a proton will virtually never be able to pull the F- out of fluoroapatite as it would the OH from hydroxyapatite, and there you have acid-proof tooth structure.  As a dentist, I never really thought about the effect of alkaline on teeth, but seeing how the theory promoted by the texts and professors is that the OH is pulled from the tooth by protons, alkaline would be able to accomplish no such similar thing.  DRosenbach  ( Talk 02:58, 4 March 2010 (UTC)


 * Thanks. With that I'm marking this Q as resolved, as "alkaline foods and drinks are rare, and, even then, they don't cause tooth decay". StuRat (talk) 16:13, 5 March 2010 (UTC)

Another alkaline food would be Century egg a resonably common Chinese ingredient in East and South East Asian food. However unless the egg is eaten by itself (which it is) the prepared food may not be alkaline. We also have Food preservation albeit without much other then what's discussed here. Lye has a bit more, although probably not all of those are alkaline after treatment, you'd have to check out the individual articles or whatever to find out. Nil Einne (talk) 06:00, 12 March 2010 (UTC)

Fire drills
I've often thought that fire drills might actually harm more people than they help, when people, especially kids, are forced to stand outside in the cold, without coats, for hours at a time. I'd also include over-reactions, like when a waste-paper basket catches fire and is immediately extinguished, but the entire building is evacuated anyway until the fire department comes out and gives the "all clear". So, my questions are as follows:

1) Is the potential harm done to people by having them stand out in the cold without coats considered when scheduling drills, or reacting to minor fires ?

2) Does any jurisdiction prescribe methods for handling this, such as having blankets available in a shed in the evacuation area or a plan to move evacuees to a warm building nearby ? StuRat (talk) 17:15, 3 March 2010 (UTC)


 * Can you cite a source for the claim that fire drills cause people to stand outside in the cold without coats "for hours at a time"? Can you cite a source that standing in the cold causes harm to people?  I mean, it's uncomfortable and annoying, but people aren't dropping dead from hypothermia during a fire drill, and the common cold is not contracted via exposure to colder weather.  Comet Tuttle (talk) 17:36, 3 March 2010 (UTC)


 * I just saw a case on TV where kids were outside for 2 hours, and shivering severely, until a bus came to take them someplace warmer. In this case it was a bomb threat, but I've personally seen fire drills and reactions to minor fire events that have involved similar-length evacuations. StuRat (talk) 18:00, 3 March 2010 (UTC)


 * Given that the fire, the smoke from fire, or the panic from being unprepared for said fire all account for many many tragic deaths each year, I am going to venture the argument that spending 5 to 10 minutes outside in 'uncomfortable' weather to instill good fire preparedness is well worth it. If you are really standing outside for hours on end for a drill, or are doing it during truly inclement weather, your safety coordinator probably needs to find a new outlet for his masochism.  Where I am in the US, we do fire drills every so often, and it's not on a bad weather day (since there is discretion during planning for a drill) and it never takes more than about 5 minutes of my time.  Were this a high-rise building of some sort, I could see it taking maybe 15 minutes to get everyone out, accounted for, and back in but if the process to conduct the drill takes hours on end, imagine the hassle of fleeing an *actual* fire! --144.191.148.3 (talk) 17:51, 3 March 2010 (UTC)


 * But keep in mind that people probably evacuate 1000 times for every actual life-threatening fire. So, if only a few kids get sick each time, it may end up worse than the many injuries and deaths in actual severe fires. StuRat (talk) 18:00, 3 March 2010 (UTC)


 * It's one thing to say a few kids get sick, and a whole 'nother thing to say they get sick enough to perish. --Sean 19:59, 3 March 2010 (UTC)


 * Not really. Anything that makes thousands of kids sick (like millions of kids forced outside in the cold without coats) will probably kill a few of them, either directly or indirectly, as when their immunity is still low when they get some other fatal condition, or when the doctors kill them via medical error.  The problem, though, is that the death certificate won't say "killed by a fire drill", so no statistics will be kept or action taken to prevent further such deaths. StuRat (talk) 20:11, 3 March 2010 (UTC)


 * As for evacuating a building for minor fires...Personal experience: two peoples' work went up in flames when someone (I think) knocked over a Bunsen burner in a chemistry lesson. The teacher came long, tipped the flaming work into the sink, then continued with the lesson. (The sink was wet; the fire went out almost immediately). No alarms, no evacuations, no-one had to leave the room. But, I live in Britain; where are you writing from? And to add to what the others have said - our drills were 10-15 minutes, and our accidental alarms were about 20. Vimescarrot (talk) 17:57, 3 March 2010 (UTC)


 * Well, if it never triggers the alarm, that might happen here in the US, too. But once an alarm goes off, I think schools are obligated to do a full evacuation.  There are places in the US where the temp goes down to -40 in winter, and even a few minutes at those temps without coats could cause medical problems, even death. StuRat (talk) 18:03, 3 March 2010 (UTC)


 * The problem with fire is how rapidly something that "looks" small can become a huge and threatening danger. The general public is terrible at recognizing that fact, and even in cases where someone recognizes the real extent of a developing disaster, how do you convince others that they need to react a certain way, now, without panicing? And children certainly don't have the the experience to recognize and react properly to emergencies or the urgency of "get out now" vs "if you're a few minutes late wandering out for recess, that's okay". So instead, we have a plan that works in all normal situations rather than relying on those who are maybe not capable of making the correct judgement (and finding that person, and having him/her examine/decide, which takes time, etc.). And drills are a rehearsal so that when the actual performance comes, you don't have to figure out and read the instructions for the very first time in a situation where there isn't time. It's easy: "fire? pull alarm." "fire alarm? get out."--the potential for harm (and harm to others not just self) if you make either of those optional/judgement is huge. Modern buildings often have fire-alarm zones, so pulling in one area doesn't dump other areas, but that requires more complicated wiring of the alarm system and (more importantly) that the areas are strongly firewalled from each other. Different wings of a sprawling complex are like this. Also, tall buildings are sometimes zoned "alarm floor and the one immediately above it". That latter is interesting...it recognizes that fire tends to go up and that stairwells are a often bottle-neck so best to get the most-threatened people out asap rather than clogging the exit with downstairs people. Getting back to the risk/trade-off, somehow we ("public policy in the US") lean heavily towards "better safe than sorry", even if there are health risks and real costs of that safety. We usually go to an extreme to prevent disasters or react properly to them, even if they are likely to be rare, because disasters are so disasterous and unpredictable.
 * One of the funniest (in a scary way) things I've seen is a lab-safety training session on using fire extenguishers. Now this is a place where fires are a real possibility, they are detected immediately, can be extinguished rapidly, and if so there is little risk of spreading (but if not, can easily take out the whole building). And everyone knows "read the instructions on the extinguisher" (and even most knew "PASS-- pull, aim, squeeze, sweep"). So everyone's given an extinguisher and told "now use it". Usually takes several minutes (!) before the first person actually gets it discharged, and this was not in a panic with real risks as time runs and where the situation itself isn't predictable. DMacks (talk) 19:14, 3 March 2010 (UTC)


 * It actually might go better in a real fire, as nobody would try reading the instructions, which are probably full of time-wasting advice like "never insert the hose into your anus". :-) I hope I didn't put beans up anybody's nose :-) StuRat (talk) 19:24, 3 March 2010 (UTC)


 * Schools in the U.S. always did the fire drill, but after the Our Lady of the Angels School fire in 1958 killed 92 children and three nuns, when a fire started in the old firetrap school,  there was a delay sounding the alarm, the wrong address was given to the fire department, and there was a lack of fire escapes, school fire safety became a much greater concern, and the drills were taken seriously. Did all parts of the building hear the promptly sounded alarm, and did they line up and leave in an orderly fashion in an acceptably short time? In a 1954 fire referenced in the first article,860 students in "Gadsden" safely exited in 2 minutes.  Strangely, in one 1956 school fire, the Principal told the students it was just a fire drill, "to prevent panic." At Our Lady, a teacher escorted her pupils out, then went to notify someone in authority, rather than someone seeing smoke minutes earlier and sounding a central alarm.  That fire also resulted in physical safety improvements, like better fire alarms and the installation of lockers in hallways to prevent clothing on pegs feeding the fire. Schools in the U.S. and elsewhere were inspected and many old schools were promptly closed. The frequency of fire drill was increased. Millions were spent on alarms, sprinklers and improved fire escapes, including security doors which opened automatically in a fire, and automatic alarms to fire stations. . Fireproofing was added to over 16000 schools in the U.S. as a result of the fire, and 68 % of U.S. communities adopted stricter fire codes for schools. Edison (talk) 19:25, 3 March 2010 (UTC)


 * And I'd be in favor of most of those things, but that doesn't mean nothing should be done to protect kids from cold during drills and actual fires. As for modern risks, I bet many inner-city schools chain the doors shut during the day, to prevent unauthorized access to the school by drug pushers and such.  Unfortunately, I doubt if a fire drill would address such an issue, as the staff would just unchain the doors before the drill, then chain them back up again after recording a successful evacuation.  A kid pulling a fire alarm would actually be a better test of whether the staff can get the doors open in time. StuRat (talk) 19:56, 3 March 2010 (UTC)


 * I know of no school which does that (and I have friends who teach high school in the Bronx). Unless you have a source, that sounds incredibly unlikely, due to the safety implications you mention. It's much simpler to simply make doors that can only be opened from the inside (without a key), and doors like those are used on many, many schools, not just those in the "inner city". &mdash;ShadowRanger (talk 20:07, 3 March 2010 (UTC)


 * Here's a source: . Doors that open from the inside only can still be used for criminal acivity with an accomplice on the inside, such as the student who wants to buy the drugs. You probably need a guard (possibly armed) at each door to both keep criminals out and allow a quick exit in the case of a fire, and that would be expensive. StuRat (talk) 20:42, 3 March 2010 (UTC)


 * Or you just alarm the door so the fire alarm goes off if opened, that way someone can't use it to sneak drugs into the school and it still works as a fire door. 82.132.139.83 (talk) 22:48, 4 March 2010 (UTC)


 * That was mentioned elsewhere. Kid opens door and gets drugs, alarm goes off, kid runs like hell and gets away, guards get pissed and chain door shut. StuRat (talk) 01:17, 5 March 2010 (UTC)

See the article Fire drill. The regularity of fire drills may be set by local authority rules. Examples in US. The purpose of the drill is to assess how long it takes to confirm that everyone has evacuated which imposes a certain waiting time that may be uncomfortable, though real harm to anyone is unexpected. Fire protection equipment such as blankets, hoses, extinguishers and alarms in a building is for immediate emergency response and dealing with unharmed evacuees is not a priority. Cuddlyable3 (talk) 20:45, 3 March 2010 (UTC)


 * They should do a proper cost/benefit analysis of fire drills, which includes a proper evaluation of the down side of such drills. I would expect them still to be worthwhile, but some measures should probably be taken to limit risks to kids during drills. There's also the risk that fire alarms can be used by terrorists to get kids outside where they can be attacked and killed, as they were here: . StuRat (talk) 21:38, 3 March 2010 (UTC)


 * As opposed to the cost of paying out multi-million dollar wrongful death settlements after an actual fire kills some of your students? Or any number of other issues that chaining the doors shut would cause? They hire the security anyway, because the students themselves can be drug dealers or become violent. The easy solution to the case you describe is to have most of the doors alarmed. Then you only need one or two guards to cover the doors without alarms that are used regularly. Since the schools already have metal detectors installed, they need one or two guards to man them in the morning. You're being intentionally obtuse; try and think about what you're saying for a second or two before posting drivel. &mdash;ShadowRanger (talk 20:51, 3 March 2010 (UTC)


 * "The door is alarmed ? Why, did you threaten to chop it up with an axe ?" :-) StuRat (talk) 21:10, 3 March 2010 (UTC)


 * Please don't get abusive. A door with an alarm on it isn't necessarily effective, as the kid who opens the door can probably run and hide before anyone responds to the alarm and catches him.  Adding a video camera would help, but the kid could always cover his face as he opens the door, gets some drugs from someone outside, then run and hide.  After this happens several times, the guards might stop responding altogether. All those doors with alarms and video cameras would also start to get expensive. One or two guards won't stop this, you'd need one for every door.  As for the cost of a multi-million dollar lawsuit, the administrator who orders the door locked won't pay any portion of that, and, if there isn't a fire, they aren't likely to be punished at all. StuRat (talk) 21:10, 3 March 2010 (UTC)


 * By law, there needs to be a certain number of exits available, well-signed and accessible, that can be nearly instantly operated by nearly anyone. Your local fire marshal would be happy to give the building manager the option of either unblocking them or else having their occupancy permit revoked for violation of building/life-safety code, and your local news media would love to do an investigative report of a school (especially one in New York) that didn't learn from the Triangle Shirtwaist Factory fire. One popular design is doors with have electronic locks that unlock automatically by fire-alarm system. DMacks (talk) 20:55, 3 March 2010 (UTC)


 * I don't trust "automatic" locks not to lock people in during a fire. Some fairly complex electronics needs to work properly for the fire to be detected and for the doors to open. StuRat (talk) 21:30, 3 March 2010 (UTC)


 * Trust (or not) is certainly your prerogative, but "cut power to electromagnet" doesn't seem more complex than "send power to bell-ringer". DMacks (talk) 21:33, 3 March 2010 (UTC)


 * It's how to determine when to cut that power that's the issue. Do you do it when a fire alarm is pulled ?  Then the kid who wants his drugs will pull the alarm, open the door, and get his drugs.  Do you open the doors when a smoke detector is triggered ?  Then the kids smoking in the bathroom will trigger it.  How many times does this happen before somebody disables the door release circuit ?  And, unlike a chained door, a disabled automatic lock isn't apparent until the actual fire.  Also, if the alarm bell fails, there are backups, like the PA system or even somebody running down the halls yelling "Fire !", but what backup is there for an automatic door that won't unlock ? StuRat (talk) 21:47, 3 March 2010 (UTC)


 * I'm sure it's illegal to chain the doors shut, but that won't stop people from doing so. There would need to be wide-scale random inspections and long prison sentences whenever a violator was found, to have any hope of actually stopping this. StuRat (talk) 21:01, 3 March 2010 (UTC)


 * Why precisely would they do it? You're assuming people are doing it without giving a legitimate reason for them to do so, particularly given the consequences of violation. You can't assume something bad is happening and then demand something be done. Prove your case. Give one example of a school currently using this practice. Myths like this about inner city schools are based in ignorance and racism. &mdash;ShadowRanger (talk 21:05, 3 March 2010 (UTC)


 * I already gave a source, here: . The consequences to the person who orders the door chained are probably nothing more than a slap on the wrist (unless they get caught in a fire, that is).  They would do it to prevent criminal activity (with no money budgeted to hire guards), which is far more likely than a fire.  It's hardly an ignorant, racist myth that criminal activity is a problem in inner city schools, do you really need me to find a source to support this, too ?  Please stop being abusive. StuRat (talk) 21:15, 3 March 2010 (UTC)


 * The source you gave answers your question: there are random inspections, there are directives issued, there is public outcry for change, there are fines for non-compliance. I have to agree with others, you seem to have a preconceived idea of a problem and are asking us to either prove you wrong or somehow else argue about it and criticize public policy you disagree with. To answer your original question (again as others have) yes, fire-drills are scheduled to be somewhat convenient/minimize disruption/etc and yes, some places do not just dump the whole building outside for extended periods. Do you have any further science question about this topic? DMacks (talk) 04:35, 4 March 2010 (UTC)


 * Obviously, once it reaches the newspapers the problem will be addressed, at least for a while. The problem is all those cases that have so far avoided public scrutiny.  The percentage of schools with illegally locked doors will reach an equilibrium in each area, with factors like widespread, truly random inspections and severe punishment for those who locked the doors (not a fine for the school) tending to move the percentage down.  Also, kids who tell their parents and the press about it might help, too, but that only works if the locked doors are visually apparent.  Automatic unlocking doors that would fail to open in a fire aren't visually apparent and thus such a method wouldn't work on them.  Also, some time after a public outcry over locked doors, I'd expect the inspections to go down, and possibly be scheduled for specific dates, resulting in administrators illegally locking the doors again and only unlocking them on inspection days.  Also, low safety and security budgets will lead to this cheap "quick fix".  And yes, I do want more scientific info.  What specific measures are taken to keep kids from the cold ?  Where are these taken and at what times of the year ?  I'd also like sources. StuRat (talk) 14:32, 4 March 2010 (UTC)


 * If kids were really standing for hours outside during a drill, then the folks running it are idiots incompetent. The purpose of a drill is not to make you stand outside in the cold, it's to get you familiar with the evacuation process. And if it's actually a fire, you're better off outside the building than inside it. ←Baseball Bugs What's up, Doc? carrots→ 04:49, 4 March 2010 (UTC)


 * That would depend on the type of fire. In the example I gave earlier, of a waste-paper basket that caught fire when a ciggy was tossed in, was thoroughly extinguished, and is now sitting outside, filled with water; an evacuation could do more harm than good.  Another example would be a pot of food that went dry and caught fire in the kitchen area, was immediately covered and extinguished, but set off the smoke detector anyway.  I'd say that most fires are like this, with only a few escalating to life-threatening status. StuRat (talk) 14:39, 4 March 2010 (UTC)


 * The problem you seem to be missing is that by the time you've identified the cause, it's a bit late to evacuate if it's a serious fire. So that's why you don't do it. If the alarm goes off, you evacuate. Once you've identified the cause and determined it's safe, then you go back in. You don't wait until you know whether it's a serious fire before evacuating. Nil Einne (talk) 14:25, 5 March 2010 (UTC)


 * That's sometimes true, but a person is often present at the site of ignition, such as a cook at a kitchen fire. I was personally present at a "fire" where a waste-paper basket with a ciggy in it lit up, and saw the whole building being evacuated as a result (I was in the building, but somebody else was the witness to the start of the fire). StuRat (talk) 17:12, 5 March 2010 (UTC)


 * Yes but how do you relay this information in time to prevent an evacuation? And cancelling an evacuation that's in progress is likely to lead to confusion and may be even chaos and could easily cause injury. Also how do you establish a level of trust to ensure this information is reliable. E.g. what happens if someone maliciosly says the fire was only a minor thing? Or if two fires happen simultaneously (again particularly possible if it's malicious)? Or if someone misidentifies the cause of the alarm OR thinks it's out but isn't? No as I said before, the evacuation should start as soon as the alarm goes off, waiting until you find out whether it's a serious fire or not just doesn't work. Once a person entrused with the responsibility has verified there's no risk you can return to the building. Nil Einne (talk) 09:33, 6 March 2010 (UTC)


 * In some cases no smoke detector triggers, but they just follow a policy of fully evacuating the building when there is any fire. This is what happened in the waste-paper basket fire I've talked about elsewhere.  The person who witnessed it fully extinguished it, and called the fire department, since we are required to report all fires.  The FD then responded with 2 full ladder trucks, 2 ambulances, and two cars, and pulled an alarm to fully evacuate the building.  I have to question whether this massive response was really the best use of resources, considering the risk of insufficient manpower and equipment if a real fire happened at the same time, elsewhere. StuRat (talk) 14:16, 6 March 2010 (UTC)


 * I don't know how things work in the US, but here in NZ if the fire alarm goes off (usually due to a smoke alarm) in any commercial building and I presume schools as well, you always evacuate, I presume it's mandatory. The fire service will come (an automatoic signal being sent went the alarm goes off) and checks out the alarm, if it's a false alarm they'll disable it. Most/all? buildings get one free call out per year, any further callouts will cost usually I believe NZ$1000 (although it may vary depending one the circumstances and I'm not sure if this applies to schools). This may not seem like much, but I'm pretty sure it's enough to ensure most buildings avoid false fire alarms. Of course I'm not saying it doesn't happen, you do see it resonably often (fire trucks and people standing outside) most commonly I assume it's mostly a false alarm (e.g. someone in the eatery burnt fish). Nil Einne (talk) 08:09, 4 March 2010 (UTC)


 * Fines for false alarms would tend to lower fire safety, by causing the building managers to disable the alarms to avoid further fines. StuRat (talk) 14:35, 4 March 2010 (UTC)


 * I don't think disabling the alarms is easy (remember these things automatically warn the fire station, if you try to fool around with them, there's probably a fair chance you'll end up sending off a warning) and it would likely carry a severe penalty (when caught by spot checks etc) and I've seen no evidence it's a regular occurance or a real problem. There's also the issue of mentality I guess. Perhaps in the US, the mentality is such that many managers would do such a thing and it wouldn't surprise me if you saw similar behaviour in Malaysia for example, but I suspect the mentality here in NZ is such that it doesn't happen that often. Also, I suspect the person who owns the building doesn't pay the cost in many cases anyway. If a restaurant sets off the smoke alarm due to burning fish, the restaurant pays. The owner isn't going to turn off the alarm, which other then the penalties involved, would likely affect their insurance because some tenant keeps setting off the alarm. Yes this may not apply to schools, but they aren't really a typical business in particular for any public school, there's likely a risk to the principals job if they pull off crap like that and in any case, there are likely plenty of people in the school who would be aware if this went on and they'll generally have the ability to get something done about it if they find out. Of course, this probably occurs with many commercial properties anyway in many cases the owner may be at arm's length from the management and if there are problems, with frequent false alarms, they'll expect the management to deal with it but if they deal with it by disabling the alarm, there's a far chance the owner isn't going to be pleased. Also it's not primairly intended to be a fine but a cost recovery exercise. Nil Einne (talk) 14:14, 5 March 2010 (UTC)


 * I think, rather than just giving them a fine, the fire department should work with the building owners, managers, and occupants to come up with a plan to keep the alarms functional, but also prevent further false alarms. I have an aunt who had an alarm go off every time she cooked, and I just moved the smoke detector further away from the kitchen, and the problem was solved.  Of course, one could argue that this won't provide as quick of a warning of a fire that starts in the kitchen, but she was at the point of pulling the batteries out to disable it altogether, so my solution is certainly preferable to that.  In a commercial setting, another option might be upgrading the ventilation system in a commercial kitchen to get smoke out of there before it builds to a point that triggers an alarm. StuRat (talk) 16:09, 5 March 2010 (UTC)


 * I'm sure they do, I never said they didn't. Even more so if they ask for this sort of help or there's an obvious reason/solution for the false alarms that can be avoided. For a related example    mention reducing false or unnecessary callouts from a general standpoint. (Where is my building's nearest Communication Center?) &  suggest people contact them before doing trial evacuations and controlled fires to reduce the risk of unnecessary call outs. However it is ultimately the building owner's resonability and it's entirely resonable if you are incurring additional costs by causing frequent call-outs you should pay for it and this does provide an incentive for the people to actually fix the problem rather then ignoring it. Note that the New Zealand Fire Service is funded solely by insurance levies so it isn't even taxpayer money we're talking about here (not that I consider that matters). Nil Einne (talk) 09:33, 6 March 2010 (UTC)


 * Some of those links are a bit off topic, such as the policy on intentionally setting outdoor fires. I think resolving false alarms should be thought of as everyone's responsibility, not just the building owner, as they are more likely to just disable the alarm system than the occupants or fire department are. StuRat (talk) 14:03, 6 March 2010 (UTC)


 * You've still not cited a source that standing outside in the cold during a fire drill has made anyone sick. Comet Tuttle (talk) 17:29, 4 March 2010 (UTC)


 * Here's a chart showing that frostbite can occur in 15 minutes or less at -10F with only a 5 mph wind: . I'd expect that even a fast fire drill takes about that long.  Hopefully they avoid fire drills when it's that cold (although I'd still like a source with a policy on that), but that still leaves open the other part of my Q, how they deal with false alarms (and real fires) in cold temps to reduce this possibility. StuRat (talk) 18:05, 4 March 2010 (UTC)


 * Nice chart, but, again, you have not cited a source that standing outside in the cold during a fire drill has made anyone sick. I think it's laudable that you think that cost-benefit analyses are worthwhile, but I don't see a lot of evidence here demanding a reaction.  Comet Tuttle (talk) 18:40, 4 March 2010 (UTC)


 * Well, it's circular logic to say that we shouldn't study hypothermia from fire drills unless we have proof that it exists from existing studies on hypothermia from fire drills. But what part of the logic chain do you doubt, exactly ?  That fire evacuations happen when it's that cold or windy ?  That they can last for 15 minutes ?  Or that, as the chart states, this can cause frostbite ?  Lacking any actual studies on hypothermia from fire drills/evacuations, the best we can do is to look at the components that would lead to hypothermia. StuRat (talk) 19:13, 4 March 2010 (UTC)


 * The part I doubt is your repeated implication that the adults supervising the kids are so clueless as to not use their common sense to deal with a cold day. If it is so cold as to actually cause frostbite in a few minutes' exposure, then any adult will find a way to deal with the situation.  The kids are not being ordered to stand outside by some computer algorithm that hasn't the capability to deal with corner cases.  I think your inability to cite sources for fire-drill injuries may be demonstrating that, yes, because of the presence of humans in the loop, there is no problem to solve here.  Comet Tuttle (talk) 07:08, 6 March 2010 (UTC)


 * Many of the methods which could be used to prevent exposure would require pre-planning, such as blankets in a shed or having access to a building they can use for warming up (you can't just jam 1000 students into the nearest McDonalds). If there are no blankets, or the shed/building in question is locked and nobody has a key handy, it would be difficult to resolve these issues in the 15 minutes before kids start to suffer from the effects of the cold.  That's why I asked for some indication that this is planned for, in advance, and wanted to know what type of planning they do for such a situation.  There's also obviously a difference between drills, which can be skipped on bad weather days, and actual alarms, which can't, so different plans may be needed for each (such as "avoid drills when the wind chill factor is below X, and evacuate to the community center when an actual alarm goes off on days with a wind chill factor below Y").  Here's a letter from a parent pissed off at a cold weather fire drill: . StuRat (talk) 13:47, 6 March 2010 (UTC)


 * When I was in high school, we did fire drills (and one actual fire) under cold-weather conditions: instead of evacuating outside, everyone evacuated to the semi-detached cafeteria. The building had been designed for exactly that purpose, with two firewalls rated for half an hour each between the cafeteria and the main school building.  I expect that most schools in cold-weather areas have similar plans. --Carnildo (talk) 01:40, 5 March 2010 (UTC)


 * Thanks for that. You know, you're the first person to actually provide an answer to part of my question, rather than ask me to prove the assumptions in it ?  Well done. StuRat (talk) 12:56, 5 March 2010 (UTC)


 * Of course it's not that hard to find actual references. For example a very quick search finds says that a fire drill was delayed because of cold weather and  says students are allowed to pick up coats etc provided it doesn't take extra time. Of course there's also  and  which are complaints about fire drills in cold weather Nil Einne (talk) 14:33, 5 March 2010 (UTC)


 * Thanks for those. I still get the impression that they look at it solely from the POV of making students uncomfortable, though, and not an actual risk to their health.  That part about only being able to get coats "if it doesn't take any time" seems a bit silly, as other fire regulations require that coats be stowed in lockers, which, of course, require time to open.  The last two sources are also from students and a parent, but I'm still looking for some official policy saying "fire drills will not be conducted when the wind chill factor is below X". StuRat (talk) 15:56, 5 March 2010 (UTC)


 * Can you show the regulations relevant to Vineland that require coats be stowed in lockers? It's possible that other jurisdictions have such requirements, but it's not really relevant to Vineland if they don't. You can debate whether they should but that really seems to be getting OT. (In other words, they have these regulations which work for them, they may not work for everyone but of course there may never be a universal solution.) Of course the regulations on firedrills are from 1997 so it's possible they never bothered to update them if the regulations on coats in lockers are new. Nil Einne (talk) 09:16, 6 March 2010 (UTC)


 * A short, simple answer: Not from a school, because I'm a chief fire warden (house warden/building warden) in a high rise building housing a couple of thousand people - rather than a low rise school.
 * The process:
 * Someone sets a kitchen microwave to two hours instead of two minutes
 * Fire alarm goes off. Evacuation tone sounds on the affected area, on the floor above and the floor below. Three people on the affected floor know why the alarm is going off, but staff are very well trained to leave immediately in case of a fire alarm.
 * Fire alarm goes off on the the next floor up and next floor down.
 * Chief fire warden and team arrive at the fire control panel, attempt to contact the affected floor. Too bad, they've evacuated. Alarm panel shows three smoke alarms triggered, and five floors evacuated or evacuating. It's a very easy decision to evacuate the rest of the building.
 * Everyone (except the chief warden team) gets to stand around in the cold waiting to be let back in, word filters around that the evac was caused by some overcooked chicken - smoke but no fire.
 * Someone on the chief warden team gets to escort the fire fighters to the alarm floor (wondering whether there is a fire, and noting that s/he is the only person present not wearing fire proof clothing), they find a lot of smoke, but no fire, the microwave is warped and dead and is the obvious cause.
 * the all clear is declared.
 * Sure there were people who knew what was happening, but IF YOU HEAR THE EVAC TONE YOU LEAVE BY THE NEAREST FIRE EXIT IMMEDIATELY, and happily break the glass on the break-glass-to-exit if the door isn't already open. Because building fires get very dangerous, very quickly. There was absolutely no chance of anyone being on the alarm floor by the time there is someone in the control room to ask what the problem is. It is very difficult for an evacuated person to get a message to the chief warden team before evacuation is ordered for the whole building.
 * Now if you scale that down to a single or double story building, alarms will generally trigger immediately in the entire building and people are able to evacuate out of several doors very quickly. There is absolutely no hope of someone checking and silencing an alarm before the automatic systems have gotten everyone out.
 * Would you want to slow the whole thing down so a human could get into the control loop sooner? I personally would prefer 100 unnecessary evacuations for each necessary one over no unnecessary evacuations and any real ones to happen only after a fire is well established.
 * And outside, freezing in a trial evacuation? I doubt it. I know we conduct our trials evacuations in late spring or early autumn.
 * Bomb threat? I personally would much rather be half a kilometre away from the building with the rest of the staff rather than being in the control room under the building in the case of a real bombing.
 * --Polysylabic Pseudonym (talk) 16:24, 7 March 2010 (UTC)


 * On the 2-hour cold weather bomb threat, I absolutely agree with the evacuation, but would argue that more of an effort should have been made to keep the evacuated students warm, and this probably requires planning in advance, which didn't appear to have happened, in this case. I disagree that 100 unnecessary evacs are fine, though, as human nature is such that when you "cry wolf" so many times, people start to ignore it.  In this case it could either lead to people disabling the alarms/detectors or to them ignoring them when they go off.  Now, as for how to avoid unnecessary alarms, that may need to be approached on a case-by-case basis.  I was in a building that had a microwave catch fire in just about the exact same scenario as you described.  Perhaps microwaves which only have a 5 minute timer are the answer (the person could always cook it a bit more if it's not done by then).  (You could also ban microwaves entirely, but that would probably just result in people hiding them, possibly in closets full of flammable material.) StuRat (talk) 20:57, 7 March 2010 (UTC)

Is there a type of Bee/Wasp/Hornet that doesn't have a stinger?
A friend of mine mentioned this. He said it doesn't have a stinger, but it drops something on you that burns. And if you swat it on your skin, it leaves behind a residue that also burns. Does such a thing exist? ScienceApe (talk) 17:19, 3 March 2010 (UTC)


 * I've never heard of the burning substance part, but there are flies (no stinger) that mimic bees as a defensive measure. StuRat (talk) 17:25, 3 March 2010 (UTC)


 * The drones of many bee species lack a stinger, and other bee species (e.g. the mason bee) possess stingers but generally don't use them except when directly attacked (squeezed, stepped on, etc.), as they lack the territorial instincts of the honeybee. I don't know of any species with a contact venom. &mdash;ShadowRanger (talk 19:07, 3 March 2010 (UTC)


 * Not a hornet, but see bombardier beetle (which is probably what your friend is thinking of) and perhaps assassin bug. Matt Deres (talk) 21:25, 3 March 2010 (UTC)
 * Perhaps your friend lived in ancient Canaan -- see here.  DRosenbach  ( Talk 03:01, 4 March 2010 (UTC)
 * See stingless bee for stingless bees, but as MD says, your friend is likely talking about a non-bee. --Sean 20:58, 4 March 2010 (UTC)

anti-gravaton beam
In a surprisingly large number of Star Trek episodes the use of an "anti-gravaton beam" is employed to solve various problems; collapsing wormholes, disabling shields and deactivating mines to name but a few. What exactly is an "anti-gravaton beam"? Does such technology currently exist? —Preceding unsigned comment added by ShadowFire101001 (talk • contribs) 17:57, 3 March 2010 (UTC)


 * What is it? Nothing, it's completely fictional. The idea would be that a graviton would be a gravity-producing particle, so an anti-graviton would produce anti-gravity (a general repulsive force). You could use it to push things. Vimescarrot (talk) 18:00, 3 March 2010 (UTC)


 * Which in fact would clash with general relativity. The whole theory is hypothetical and has not even reached any mathematical formulation yet. noisy   jinx  huh? 18:07, 3 March 2010 (UTC)
 * From Memory Alpha
 * Anti-gravity refers to the state in which an object defies the laws of gravity.
 * I take this to mean that an anti-graviton beam is something of a MacGuffin. Subryonic compound (talk) 18:16, 3 March 2010 (UTC)


 * I personally like the idea of anti-gravity, emanating from galactic voids, pushing the galaxies apart from each other and also compacting each one together. This would explain both the observations that the universe is expanding at an ever-increasing rate and that galaxies seem to have insufficient mass to hold themselves together by gravity alone.  This also relates to the topics of dark matter and/or dark energy. StuRat (talk) 18:16, 3 March 2010 (UTC)


 * I believe that in current theory, the graviton's antiparticle is also the graviton. So an anti-graviton would be sort of like "unobtainium".  It's completely fictional, and so transparently so that you can ascribe any properties you like to it. APL (talk) 20:19, 3 March 2010 (UTC)


 * As transparent as transparent aluminum ? :-) StuRat (talk) 20:36, 3 March 2010 (UTC)
 * It can not be as useful as ejecting the warp core Googlemeister (talk) 21:50, 3 March 2010 (UTC)


 * When Dr. McCoy used one of his instruments to scan a person's body, the instrument he was using was actually a salt shaker. A subliminal message to take any preposterous-sounding technology with a few grains of salt. ←Baseball Bugs What's up, Doc? carrots→ 04:53, 4 March 2010 (UTC)

theory of relativity
Apparently Albert Einstine didn't invent the theory of realitivy he just modified an early theory. Is this true? Who was the original author? —Preceding unsigned comment added by Delvenore (talk • contribs) 18:09, 3 March 2010 (UTC)


 * Since you are the one claiming that such a theory existed, may be you should be telling us who did it. As far as I know there was not such a theory. Dauto (talk) 18:16, 3 March 2010 (UTC)


 * Perhaps you are thinking of the work of Lorentz? -- Coneslayer (talk) 18:17, 3 March 2010 (UTC)


 * Maybe these articles will help. History of special relativity / History of general relativity. --Mark PEA (talk) 18:19, 3 March 2010 (UTC)


 * I think Minkowski did some work on this stuff. —Preceding unsigned comment added by RubberBeaver (talk • contribs) 20:59, 3 March 2010 (UTC)


 * Einstein's work was indeed based (like all scientific theories) on the work of others. The general ideas that are contained in the theory special relativity are very similar to lines of thought being pursued by Hendrik Lorentz, Henri Poincaré, and others at the time. However, Einstein's work was in many ways quite different than both Lorentz's and Poincaré's. In retrospect, people go, "oh, it's the same thing!" mostly because they don't know how to distinguish them (e.g. why the Lorentz contraction is doing something different in special relativity than it is in Lorentz's ether theory), and because they have been sold a myth about how Einstein and science works, whereby a lone genius magically came up with a totally new way of seeing the world. Einstein had some really key insights, which he both derived from and merged with a lot of previous work. --Mr.98 (talk) 00:01, 4 March 2010 (UTC)


 * You might be talking about Galilean relativity. --Tango (talk) 04:57, 4 March 2010 (UTC)


 * The quote, which is attributed sometimes to Isaac Newton (its likely an old aphorism) applicable here is "If we have seen farther, it is because we have stood on the shoulders of giants." In other words, no scientist works in a vacuum.  Every scientist, even the REALLY REALLY IMPORTANT ones, like Einstein and Linus Pauling and the like, makes incrimental progress towards increasing human knowledge.  It may be helpful to think of each scientist adding some small % towards aligning our working models of the universe with the actual way the universe works.  If the average physicist contributed like 0.01% towards improving the model, and Einstein was say 1000x more important towards that model than the average phycisist, he'd still only be contributing 10% of the total picture.  So, he can still both one of the most important physicists in history, and STILL working extensively with the works of others.  -- Jayron  32  16:37, 4 March 2010 (UTC)


 * "If I have seen a little further it is by standing on the shoulders of Giants." Buddy431 (talk) 06:50, 5 March 2010 (UTC)

Antimatter
Since regular matter emits regular gravity (in the form of gravitons), does antimatter, the opposite of regular matter, emit antigravity/negative gravity? --J4\/4 &lt;talk&gt; 18:18, 3 March 2010 (UTC)


 * The graviton is still a hypothetical theory, nothing more. noisy   jinx  huh? 18:21, 3 March 2010 (UTC)


 * (ec) This might be better joined with the Q 2 questions back. Also note that the graviton is only a theoretical particle.  StuRat (talk) 18:24, 3 March 2010 (UTC)


 * (ec)Antimatter has mass equivalent to the mass of its matter counterpart; an anti-proton weighs the same as a proton. As such, it has the same gravitational attraction as matter; it doesn't cause a repulsive effect. This has not been directly observed to date (we don't have enough stable anti-matter to make any such observations), but it is the overwhelming consensus of physicists. Handily enough, we have an article on it: Gravitational interaction of antimatter &mdash;ShadowRanger (talk 18:28, 3 March 2010 (UTC)

Sunlight
Why does the sun make your skin dark but your hair light? —Preceding unsigned comment added by Transfigurations (talk • contribs) 18:45, 3 March 2010 (UTC)
 * The reaction with skin is with living cells whereas the reaction with hair is with non-living cells. 71.100.11.118 (talk) 18:56, 3 March 2010 (UTC)
 * Sunlight makes photopaper dark (even without chemical development). By your reasoning, does that imply it is living? Edison (talk) 18:59, 3 March 2010 (UTC)
 * Edson, I think if you look carefully you might spot the fallacy of your statement above. Dauto (talk) 22:12, 3 March 2010 (UTC)
 * The fallacy is in the explanation by 71.100.11.118, which I pointed out. Edison (talk) 19:57, 4 March 2010 (UTC)
 * This is not relevant to the OP but, since the question has been answered below, I'll post. 71.100 said that skin cells are living and hair cells are not therefore sunlight darkens skin while it lightens hair. Your post above implies that 71.100 said that sunlight darkens skin therefore skin cells are living. Note: 71's post was incomplete and unhelpful and inappropriate, but not fallacious. Zain Ebrahim (talk) 22:08, 4 March 2010 (UTC)


 * Sunbleaching (what, no article ?) has an effect on many objects with pigment, living and inorganic, by breaking down the pigmentation molecules, where the light stops, doing damage in the process. A suntan is a reaction to sunlight's UV damage to the skin, which causes the release of melanin, to prevent further damage.  This is a protective measure more common in people with light skin, which allows them to get the sunlight they need to produce vitamin D when sunlight exposure is low (as in winter), and yet not develop burns and skin cancer when sunlight levels are high (as in summer).  Those whose ancestors lived closer to the equator tend to have more melanin, and hence darker skin, since sunlight exposure is high there year-round.  Why doesn't hair have such a protective measure ?  It's dead (except for the follicle), so isn't susceptible to cancer or sunburn. StuRat (talk) 18:58, 3 March 2010 (UTC)

cause of exponential expansion of the universe
My studies have come to the conclusion that the Big Bang is the result of the polar force of gravity I call anti-gravity. This force is also the cause of the expansion of the universe and explanation why the universe is expanding exponentially in the presence of less gravity to slow it. However, I think this is original research and can not add it to an article. Could the reference desk please inform me if this is original research of if others have reached the same conclusion? 71.100.11.118 (talk) 18:48, 3 March 2010 (UTC)


 * If you can link us to your studies published in a peer-reviewed journal, and preferably to some secondary sources discussing the importance of your findings and how meaningful they are considered, then we can add it to an article. If you have none of these things, it is original research and cannot be added. If you have those things, I'd be surprised that you are trying to get it published in an encyclopedia: I'd have thought you have more research to do, papers to write, conferences to speak at, etc. 86.177.121.239 (talk) 18:57, 3 March 2010 (UTC)


 * Note that Wikiversity lacks Wikipedia's ban on OR, so your thoughts (which happen to be quite similar to mine) would be quite welcome there. StuRat (talk) 19:11, 3 March 2010 (UTC)
 * Done, thanks. Exponential expansion of the Universe 71.100.11.118 (talk) 21:05, 3 March 2010 (UTC)
 * Please don't add your ideas to Wikiversity. One can't usefully teach a subject that one doesn't understand, and you don't know the first thing about cosmology. I mean no offense. If you'd like to learn cosmology, I recommend Introduction to Cosmology by Barbara Ryden (ISBN 0805389121). -- BenRG (talk) 23:27, 3 March 2010 (UTC)

artificial intelligence
Have artificial intelligence reached the point where they are self aware yet? I've tried the current AIs and they always just seem to regurgitate random parts of conversations you had previously with them, they don't seem to think —Preceding unsigned comment added by Aject8886 (talk • contribs) 19:31, 3 March 2010 (UTC)


 * Definitely not. We don't even know how to do that in theory, as simply adding more processing power just leads to a more powerful calculator.  And, if we could make a self-aware computer; should we ?  There are many moral concerns, leading all the way up to the world of the Terminator movies.


 * Also note that we may someday be able to create a computer which passes the Turing test, meaning we can't tell if it's following a program or actually thinking. But, to me, this just means it's able to simulate intelligence, not that it's actually intelligent.  Is it just a new and improved Magic 8-ball ?  The answer is unclear at this time. StuRat (talk) 19:40, 3 March 2010 (UTC)
 * "Sentience" is an abstract like "Art". I don't see that there's a difference between a perfect simulation and the genuine article. APL (talk) 19:51, 3 March 2010 (UTC)
 * Or maybe it's more like stage magic. It's only real if you don't know how it works. APL (talk) 19:53, 3 March 2010 (UTC)
 * That seems to be a popular opinion. Personally I think it's nonsense.  I know very well that I am sentient, though I can't prove it to you.  Showing that a simulacrum had the same electrical patterns would not address the question at all.  --Trovatore (talk) 22:30, 3 March 2010 (UTC)
 * I didn't address electrical patterns at all.
 * I'm saying that as an abstract concept I'm not convinced that there's a difference between "real" and "exactly like real, but not".
 * If Leonardo De Vinci jumped out from behind a curtain and said "Haha! Fooled you! All of my paintings were based on mathematical equations and tedious computations and no creativity at all!" would that immediately move them from the realm of "Art" to some new realm of "Fake Art"? Of course not. There's no such thing as "Fake Art", it's a meaningless concept.  I'm no philosopher, but I honestly don't understand the difference between "Sentience" and "Fake Sentience".
 * (Note : I do, of course, understand the concept of a "soul" as some immaterial, but necessary, prerequisite for intelligence. But I do not believe this theory. )  APL (talk) 23:13, 3 March 2010 (UTC)

(After E/C with StuRat)
 * You're probably thinking of things like Megahal, and yes. Those are specifically designed to regurgitate past conversations in a vaguely believable manner. Done properly they can be very convincing for short conversations. To my knowledge there is no "Full AI" that even comes close to fictional AI's like HAL 9000. I don't think there's even a good chatter-bot that can keep up a long conversation in a logical way.
 * Most of the research into AI nowadays goes into either AIs designed to complete some specific task, or to autonomous AIs with much 'smaller' minds than you'd get in Science Fiction. The idea being to duplicate, say, an ant's mind before trying to simulator a human.
 * "Self aware" and "Sentient" are difficult terms to quantify. A more objective standard is the Turing Test. Many people argue that a computer that consistently passes the Turing test would only be "pretending", and using a complex set of rules to create its intelligence. (Personally, I'm not at all convinced that those of us with squishy brains aren't doing the same thing. The laws of chemistry are just as immutable as a computer's instruction set.) A more serious argument is that a computer that is smarter than a human would also fail the Turing test.
 * The Artificial Intelligence article is a bit of a mess, but there's still good information there, worth reading. APL (talk) 19:51, 3 March 2010 (UTC)
 * (ec)The "AI"s you've communicated with are likely variants on the ELIZA bot, which was never even intended as an AI, but rather as a limited natural language processor. Natural language processing would be required to create an AI humans could interact with a la Star Trek, and true natural language processing might require AI, but they aren't the same field. Mimicking the processing power of even a fraction of the human brain would require substantially more processing power than we are likely to be able to produce in the next few decades (at least without introducing communications delays between the components). We have no other model for AI besides the human brain, so unless there is a major leap in AI theory, we're not going to see a self-aware machine for a long time. &mdash;ShadowRanger (talk 19:53, 3 March 2010 (UTC)

Computers have been self-aware for ages. Every time you ask how much disk space is available, the computer is telling you about its internal state. Self-awareness is by no means the hardest part of artificial intelligence, in fact it's one of the easiest. And it definitely isn't the same thing as "thinking". Looie496 (talk) 21:32, 3 March 2010 (UTC)
 * I don't think that counts. Even the simplest animals can respond to internal state.  When you're hungry - you go and eat.  Knowing whether you are hungry or not is a very basic thing.  We could probably show that plants are self-aware in that sense.  Self-aware means being able to perform introspection on one's own thought processes.  The tangled mess that is the first paragraph of Self-awareness attempts to say something like that! SteveBaker (talk) 02:05, 4 March 2010 (UTC)
 * The problem here is that there isn't a test for "self-awareness" - how can you tell whether any person you bump into in the street is self aware? You can ask them "Are you self aware?" - but then the following one-line C program would pass that test:

int main { printf ( "Yes!  I am self-aware.\n" ) ; return 0 ; }

...so that's not going to work. We have no idea whether small children, dolphins, dogs, or ants are self-aware. It's possible that I'm the only entity in the universe that is self aware...and everyone else has a mindless ability to claim to be self-aware when I ask them...but you may have a different outlook than me!


 * As for AI, well, the business of building a truly intelligent system has really gotten nowhere since the 1960's. The AI community are attacking more tractable problems - things like linguistics, speech, visual recognition, knowledge representation - things that hover around the edge of actual intelligence.  The Turing test will undoubtedly be passed - and probably not long from now - but serious AI researchers don't regard that test as anything particularly meaningful these days and the thing that passes it would seem remotely intelligent to careful investigators.
 * SteveBaker (talk) 21:50, 3 March 2010 (UTC)


 * Steve, may I lend you an "n", an aposthrophe, and a "t", so you can change your "would" to a "wouldn't" ? StuRat (talk) 21:58, 3 March 2010 (UTC)


 * As long as I'm picking Steve's nits -- that one-line C program won't compile. (Don't believe me? Try it.) --Trovatore (talk) 22:22, 3 March 2010 (UTC)
 * I did and it does. There's a warning about printf being implicitly redefined, but it works fine. Gcc version is i686-apple-darwin8-gcc-4.0.1. --Stephan Schulz (talk) 23:21, 3 March 2010 (UTC)
 * Whoops, you caught me speeding &mdash; I didn't try it. I assumed you had to   in order to use  .  --Trovatore (talk) 23:46, 3 March 2010 (UTC)
 * GAh! I just ran this code (It compiled without warning here.) and now my machine claims to be self-aware! SteveBaker, WHAT HAVE YOU DONE?!? APL (talk) 00:06, 4 March 2010 (UTC)
 * But despite all this nit-picking, we don't think Steve's post was lousy, right ? StuRat (talk) 22:33, 3 March 2010 (UTC)


 * Interesting choice of words. Would you expect your letters and punctuation to be returned to you at some point in the future?


 * Yes, and I'll provide a stamped, self-addressed envelope for just that purpose. :-) StuRat (talk) 22:33, 3 March 2010 (UTC)


 * Testing a computer for self awareness is easy! It involves two colors of paint and a mirror. APL (talk) 22:28, 3 March 2010 (UTC)
 * The mirror test is an interesting experiment - but it's really meaningless when it comes to AI. I can't write a computer program that will pass the test in one line of code - but given a camera and a robot arm, I could probably do it in a few thousands of lines of code.  Definitely not something that requires intelligence or sentience. SteveBaker (talk) 02:00, 4 March 2010 (UTC)
 * Yea, I know, I was joking. Similarly, animals that can be trained to pass the mirror test are not generally thought of as having passed it. APL (talk) 02:39, 4 March 2010 (UTC)
 * Actually, that'd be an interesting program. The "Mirror test" has many variants, a general solution that could not be fooled by non-mirror images wouldn't be entirely trivial. Adding in all the usual computer-vision headaches like lighting issues and shadows, could make it a real challenge. The end result still wouldn't be "intelligent" in any general sense, of course. APL (talk) 07:11, 4 March 2010 (UTC)


 * My own opinion, the problem of artificial intelligence is constructing a computer that has intent (or even the minor form of intent called desire). It's very natural for a living creature to form an intent - even the lowest life forms seek out food, light, and other necessities of life, and humans can form complicated intentions without batting an eye, but so far the best we can accomplish with computers is programming them to make choices based on human intentions  we can't yet get a computer to have an intent of its own.  it will be a bit scary when we can, I think: with other humans, and even with animals, we can assume that their intents are reasonably similar to our own, but god knows what a computer would want if it had the capacity to want something.  -- Ludwigs 2  02:55, 4 March 2010 (UTC)
 * A Roomba has the intelligence of a grazing animal (without its sex drive) and makes less mess. Cuddlyable3 (talk) 03:25, 4 March 2010 (UTC)
 * not in the least. a roomba doesn't differentiate between what it does and doesn't suck up, it doesn't make decisions about where to go next, it doesn't choose when to vacuum and when to rest (except as it has been programmed to have logic forks, or as it is turned on or off).  your average Amoeba has greater intelligence than a roomba. -- Ludwigs 2  03:34, 4 March 2010 (UTC)
 * What makes you think I posess an amoeba? A Roomba and its cousin the Trilobite navigate around obstacles in a previously unknown area. As the article notes, a Roomba decides when to seek out its energy supply. It can wail for your help if it gets stuck. Is your amoeba intelligent enough to help with the housework? Cuddlyable3 (talk) 04:57, 4 March 2010 (UTC)
 * I have to say, when I think of "Grazing animal" I think of a relatively intelligent mammal. I suppose you're thinking of some tiny and stupid invertebrate?
 * Even so, From the Roomba article "Roombas do not map out the rooms they are cleaning. Instead, they rely on a few simple algorithms such as spiral cleaning, wall-following and random walk angle-changing after bumping into an object or wall. " APL (talk) 07:11, 4 March 2010 (UTC)
 * The kind of "AI" that computer games give to life-forms in the virtual world is very crude compared to "real" AI - and I wish we could give it another name - but it can pass a kind of 'reduced' Turing test. It's perfectly possible in some of the better networked games to be confused by who is a human-controlled player and who is a computer controlled drone.  Obviously, that fails miserably when you can talk to them - but for non-verbal stuff in a game world, it's sometimes hard to tell.
 * Anyway - one strategy for implementing this kind of thing is called "Goal Oriented Behavior" (GOB for short) - and this approach uses a hierarchy of goals and means to achieve those goals - with weightings that force some goals to be more important than others. For a typical first person shooter, the primary goal might be to obey some game-designer-issued "order", the secondary goal might be self-preservation and the tertiary goal might be to kill human players - balanced by another goal to keep the ammunition level in his gun above zero by reloading.  So it's never going to leave the precarious catwalk you placed him on - even if he's gonna get shot if he doesn't - but if he's getting shot at then he'll prefer to go and hide behind the inevitable nearby crate than to stand there like some damned idiot shooting back at you with his super-inaccurate gun at a guy with 5 lives remaining and a couple of health-packs nearby!  When he has ammo left, shooting you is more important than reloading - but when he's fired his last shot, he'll reload.
 * Seeking weighted goals is a good way to do "intelligence" on the cheap - and it's not surprising that Computer games, Amoeba and Roomba's all use it. However, it says nothing at all about sentience or self-awareness. SteveBaker (talk) 15:59, 4 March 2010 (UTC)


 * The flaw with the "mirror test" is that it sets up a test that's based on human concepts of what self-awareness is, and then concludes that anything that fails the test lacks self-awareness. That's a little like setting up an IQ test and if someone scores poorly they're assumed to be of low intelligence. All such a test really demonstrates is the ability of the subject to take that particular test. And individuals can react differently. Consider television. Some dogs and cats ignore it. Some react to the sounds of animals (their ears twitch or whatever). Others will watch the images. It occurs to me that the ones that watch the images would be the most likely to pass the mirror test, as they recognize there's something there. Animals that fail the mirror test might just not comprehend what they're seeing, or as someone pointed out earlier, since the "other" creature has no scent, the dog or cat doesn't concern itself with it. ←Baseball Bugs What's up, Doc? carrots→ 12:52, 4 March 2010 (UTC)


 * I suspect that most cats and dogs see a series of flickering still images on the TV, similar to what I see when I turn the refresh rate down on my computer screen. Why would they be able to resolve faster refresh rates than us ?  It was probably more important to them, in their evolutionary past, since they tended to hunt smaller animals that can change direction rapidly, and even a fraction of a second delay in detecting that change could cause them to lose their lunch and maybe their life.  So, those cats and dogs that do see a moving image instead of a series of still images probably just have a slower visual processing speed, not more intelligence.  Interlaced images might look even worse to pets, looking like a blurry double image. StuRat (talk) 14:10, 4 March 2010 (UTC)?


 * Dogs rarely get interested in TV's because they live in a world of smells. It doesn't matter that what they see looks like a dog and sounds like a dog - if it doesn't smell like one, it's not a dog. Period.  SteveBaker (talk) 15:59, 4 March 2010 (UTC)


 * I disagree. They most definitely use sights and sounds, as they work on a longer range.  They tend to use smells to "verify identity" at close range.  Some dogs will react to a barking dog on the TV, by going up to smell it.  Then, once they smell it, they determine that it's not really a dog after all, and ignore it. StuRat (talk) 16:13, 4 March 2010 (UTC)


 * The editor who talked about "intent" is onto it. A machine does what it's programmed to do, and nothing more, regardless of how sophisticated it is. We have only a smidgen of understanding of how the brain works. If or when we figure that out, then we'll have a clue of how to build a truly intelligent creature - a cyborg, or whatever you want to call it. But beware of the "intent" factor. If you leave out morals and conscience, you could end up with a creature that has ambitions to rule the world, or at least to kill its creator. This is a familiar theme, somehow. ←Baseball Bugs What's up, Doc? carrots→ 12:59, 4 March 2010 (UTC)


 * So would a self aware AI attempt to rewrite its own program? Googlemeister (talk) 14:15, 4 March 2010 (UTC)


 * Not necessarily. Do we try to rewrite our own ?  I suppose learning might qualify as rewriting your own program.  If so, how about an O/S that downloads new drivers to "learn" how to use new devices ? StuRat (talk) 16:01, 4 March 2010 (UTC)
 * You can train a Neural net program, which is kind of like that.20.137.18.50 (talk) 19:59, 4 March 2010 (UTC)
 * Some people do. See drug abuse, Gene therapy, immunization, Plastic surgery etc...  Googlemeister (talk) 16:17, 4 March 2010 (UTC)
 * It might want to (just as some humans would wish to) - but that's not to say that it would be able to without doing something suicidally dangerous. The authors of a 'real' AI program would certainly want to defend against that possibility (unless they were doing some kind of strange experiment or other).
 * However, at some level, "rewriting" is the same thing as "learning" - and any AI would certainly need to be able to learn. Humans can rewire their neurons just by memorizing a new telephone number - but that doesn't give us the conscious ability to demand that neuron number 123,456 connect to neuron number 987,654 on demand.  Similarly, the AI computer software would be able to add lines of Cyc code to it's database by memorizing a phone number - but would be unable to specifically compose a rule "(#$genls #$1-800-1234 #$PhoneNumber)".  That's rather important because you wouldn't want some stray thought to cause it to write something like "((#$capitalCity #$France #$WibbleWibbleI'mATeapot)" and thereby firmly believe this to be a true fact from that point onwards.  There is good reason why conscious thought can't do things like that. SteveBaker (talk) 17:00, 4 March 2010 (UTC)

anti-gravity and any violent explosion
Might not any violent explosion be a form of anti-gravity incantation or creation; a violent dismissal of gravity if you will? 71.100.11.118 (talk) 22:44, 3 March 2010 (UTC)


 * No. Explosions create force that can counteract gravity, but gravity is still in effect. Gravity is a relatively weak force though, so it may not assert itself noticeably (at a human scale of perception) at the moment of the explosion. &mdash;ShadowRanger (talk 22:52, 3 March 2010 (UTC)


 * To cover my bases: Technically, I believe whatever just exploded will no longer have the same gravitational attraction to anything within the cloud of debris. Anything outside the cloud will still be attracted in roughly the direction of the center of the debris cloud's mass, but anything inside the debris cloud would experience a weaker pull, since the debris that was blown past them will attract in a direction opposite that of the remaining debris's center of mass. Of course, unless you're blowing up planetoids, the gravitational effects from the debris would be negligible; my explanation is just being pedantic. &mdash;ShadowRanger (talk 22:57, 3 March 2010 (UTC)


 * Really technically ShadowRangerRIT you're assuming a spherically symmetric explosion which would be subject to Birkhoff's theorem (relativity), however if your explosion was large enough and wasn't spherically symmetric you would feel a gravitational effect outside of the radius of the explosion. ;)
 * But tbh your first answer was completely correct. Looked at in another way, if I throw a ball straight into the air, I'm not using anti-gravity, but giving the ball a momentum away from the centre of gravitational attraction.  Likewise when I blow up a pack of C4, anti-gravity isn't manifesting, instead chemical (potential) energy is converting into kinetic energy which gives the particles a velocity great enough to overcome not just their gravitational attraction but also their electromagnetic attraction which in this case is stronger.  To the OP check out Explosive material 82.132.248.99 (talk) 00:12, 4 March 2010 (UTC)
 * More or less why I used the term "...form of..." since the consequence appears to be more or less the same. In other words in an environment where gravity does not exist exterior to the explosion. Another situation where gravity is present exterior to the explosion for instance might be the center of a too massive Black Hole; the explosion resulting from an intolerable presence and resulting imbalance of gravity and its counterpart. 71.100.11.118 (talk) 00:56, 4 March 2010 (UTC)


 * As you wrote above, you're excited about this idea of an "opposite" of gravity, but there is no such force. See our Gravitation article.  Comet Tuttle (talk) 01:30, 4 March 2010 (UTC)
 * LOLFDL... The chasm between the realm of what might be and the realm that is assumed to be based on Wikipedia article is profoundly demonstrated by your statement. 71.100.11.118 (talk) 01:41, 4 March 2010 (UTC)
 * What might be has nothing to do with fact or science or truth - if we wrote articles about what might be, this would be an incredibly useless web site. There might be pink piano playing Aardvarks hiding in caves on the dark side of the moon - but we're not going to write articles about that. SteveBaker (talk) 01:55, 4 March 2010 (UTC)
 * oooh, another bleak assumption that anything written about here is 100% certain and without err. 71.100.11.118 (talk) 01:58, 4 March 2010 (UTC)
 * No, but read scientific method. A hypothesis is only interesting if you have some evidence to show that it might be correct.  Comet Tuttle (talk) 05:14, 4 March 2010 (UTC)
 * Is the aardvark really pink if it is not reflecting any light? Googlemeister (talk) 14:11, 4 March 2010 (UTC)
 * Yes. Definitely. It's axiomatic that pink aarvarks are pink. SteveBaker (talk) 15:42, 4 March 2010 (UTC)
 * I don't know why you'd consider a 100% correct Wikipedia to be a "bleak" outcome - perhaps you don't understand what an "encyclopedia" is all about. Certainly it's not the case that everything here is 100% correct - like any major piece of writing, it contains errors and important omissions.  However, it most certainly is our goal that everything here be both 100% correct and 100% referenced back to reliable sources so that people can satisfy themselves that we are 100% correct - and so that they can spot things which might not be because they aren't properly referenced, and fix them.  Hence, excluding things for which are false and those for which there are no reliable sources is important.  That's not to say that we can't write about patently false things like Time Cube or Perpetual motion - so long as we provide reliable sources that explain that they do not exist.  We can't write about pink piano-playing aardvarks because we have no reliable sources that say whether they do or do not exist.  Whether they actually do exist is unimportant to an encyclopedia - if there is no evidence, we can't write about it. SteveBaker (talk) 15:42, 4 March 2010 (UTC)

But you can speculate and write about things for which there is no evidence simply by qualifying your comment or writing as such. Any encyclopedia which fails to recognize this obligation is indeed one that is bleak. 71.100.11.118 (talk) 02:48, 6 March 2010 (UTC)
 * Not in this encyclopedia you can't! We have very strict rules to prevent you from doing that very thing!  No original research, No patent nonsense, No complete bollocks, There has to be evidence for everything you write here, Everything has to be notable, Speculation isn't allowed and Wikipedia is not...anything other than an encyclopedia - to name but a few!  Specifically, our "five pillars" document says: "Editors' personal experiences, interpretations, or opinions do not belong here.  Everything you write here is required to be referenced - meaning that it has to meet certain standards of evidence.  If there is no evidence for what you are writing about then you most certainly don't get to write it - no matter what qualifications you use.  This is an encyclopedia - not a work of fiction or a place to find random flights of fancy.  If you find that 'bleak' then I pity your poor sense of the joy of having most of human knowledge at your fingertips.  SteveBaker (talk) 04:03, 6 March 2010 (UTC)

What is leaching?
Please look at this. I put a link in the article which currently goes to a disambiguation page. None of the articles seem appropriate for the use since it's a process of nature rather than intentional. Vchimpanzee ·  talk  ·  contributions  · 22:48, 3 March 2010 (UTC)


 * I'd drop the link. It's a definition, not an encyclopedic topic per se. Maybe a link to wiktionary, but the term is relatively simple standard English and doesn't need to be linked. &mdash;ShadowRanger (talk 22:50, 3 March 2010 (UTC)


 * Leachate is probably the closest article on the dab page, but it's about leaching from waste sites. The idea is the same, though. -- Flyguy649 talk 22:56, 3 March 2010 (UTC)


 * I see you fixed it. Thanks. Vchimpanzee ·  talk  ·  contributions  · 14:12, 4 March 2010 (UTC)

Reversing entropy
At the current level of technological advancement of human society in 21st century, is there the possibility that entropy could be reversed? —Preceding unsigned comment added by Crockadoc (talk • contribs) 22:52, 3 March 2010 (UTC)


 * With our current level of technological development? No. And in theory, never. It's the topic of a short story, The Last Question, but even the story is indulging in hand-waving speculation. &mdash;ShadowRanger (talk 22:59, 3 March 2010 (UTC)

I added the title to the OP's question. Cuddlyable3 (talk) 01:42, 4 March 2010 (UTC)


 * Short answer: wait long enough. Long answer: it's equivalent to saying "is there a possibility that we could flip a fair coin x times and get heads every time?", where x is the amount of entropy you want to reverse (measured in the right units). If you try long enough, it will happen eventually, but there is no way of causing it. The concept of entropy really isn't part of science in the sense of the scientific method; it's a mathematical concept, with properties that can be proven by the H-theorem. This theorem basically says that lowering entropy is impossible unless whatever thing you want to lower the entropy of has been prepared in a very specific way beforehand (think of this as flipping a biased coin). Note that any process that prepares a system in such a way will inevitably increase the entropy of another system by at least as much as you are lowering the entropy of the first system. Also, if you're planning on "waiting long enough", you might want to see Boltzmann brain. 70.27.196.12 (talk) 03:40, 4 March 2010 (UTC)


 * This may be off the track a bit, but if you had a coin-tossing machine that would toss the coin in the identical way each time, wouldn't the outcome be predictable? Or are you assuming a human tossing it? ←Baseball Bugs What's up, Doc? carrots→ 07:25, 4 March 2010 (UTC)
 * I would assume he is assuming a theoretical Laplace coin of infinitesimal thickness, thrown by a spherical cow in a vaccum. --Stephan Schulz (talk) 09:59, 4 March 2010 (UTC)
 * ... and locked in a box with a cat that is both dead and alive. Gandalf61 (talk) 11:16, 4 March 2010 (UTC)
 * Coin tossing is a chaotic process - tiny changes in initial conditions can make big changes to the outcome. But it's almost certainly possible to control the situation enough to get a reliable answer.  There was a documentary on TV a while back about people who have trained themselves to beat the game of craps by learning how to roll specific numbers on a pair of dice with much higher than usual reliability - it's entirely possible that someone could learn to toss a coin reliably too.  However, in conversations of this sort, we're definitely talking about an idealized, utterly random binary outcome.  Coin tossing is the spherical cow in a frictionless vacuum of the world of statistics. SteveBaker (talk) 15:17, 4 March 2010 (UTC)


 * It was a metaphor. I said fair coin for a reason. I guess I should have made it a link the first time, but a fair coin is no more a real coin than a cow is spherical and frictionless. 76.67.78.86 (talk) 02:52, 5 March 2010 (UTC)


 * You can easily reverse entropy locally. Take a box full of kiddies building blocks - carefully sort them by color and size and pack them neatly away in their box - and the entropy of the box has been reduced.  However, it took energy to do that - or to state that scientifically: the low-entropy cornflakes that you ate for breakfast this morning got turned into higher entropy poop + high entropy heat.  The overall entropy of the universe got a bit higher, the entropy of your breakfast got a lot higher and the entropy of the bricks in the box was lowered.  We don't have any idea how to reduce the entropy of the entire universe - or any "closed system" for that matter (and it's very likely that this is totally impossible) - but we reverse entropy locally on a daily basis. SteveBaker (talk) 15:10, 4 March 2010 (UTC)


 * I once saw a video on youtube exemplifying laminar flow, but instead of linking that here, here's a description of it: http://www.fas.harvard.edu/~scidemos/NewtonianMechanics/ReversibleFluidMixing/ReversibleFluidMixing.html That isn't at all a counterexample of any law of thermodynamics, but it's a pretty neat and counterintuitive thing to see. 20.137.18.50 (talk) 20:08, 4 March 2010 (UTC)
 * There are several youtube videos showing this, this one is probably the best. It's truly an amazing thing.  Strongly counter to daily experience! SteveBaker (talk) 04:14, 5 March 2010 (UTC)

Warp Drive
Is warp power in Star Trek based on actual technology or is it all made up? Does such warp drives theoretically exist? —Preceding unsigned comment added by Velderon4 (talk • contribs) 23:05, 3 March 2010 (UTC)


 * I'd suggest reading the article on the Warp drive. Short answer: No, there is no existing technology like that, but there are certain theories that might allow for something like it, but it's purely theoretical. &mdash;ShadowRanger (talk 23:16, 3 March 2010 (UTC)


 * ( After e/c with ShadowRanger )
 * Warp Drive is not really based on any real theory.
 * The closest I've ever heard of is the theoretical Alcubierre drive. Needless to say it has a variety of practical problems. APL (talk) 23:18, 3 March 2010 (UTC)
 * The warp drive is a very useful device for telling stories in outer space, and after having read the Alcubierre drive article, it sounds like that's about all it is. Vranak (talk) 23:33, 3 March 2010 (UTC)


 * Warp drive is as real as backwards time travel, using salt shakers as medical equipment, and experiencing deja vu. ←Baseball Bugs What's up, Doc? carrots→ 04:59, 4 March 2010 (UTC)
 * Are you suggesting that deja vu doesn't exist? Because I've certainly experienced it, and the article accepts it as a real phenomenon (although one hard to induce under laboratory conditions) Buddy431 (talk) 05:40, 4 March 2010 (UTC)
 * That was a subtle hint that this question is similar to another one on the ref desk, asking if some fictional technology is for real. And all three things are "real", just not in the same way. ←Baseball Bugs What's up, Doc? carrots→ 05:47, 4 March 2010 (UTC)
 * These to name two. There's a discussion on the ref desk talk page about these questions from what could ba a series of socks or maybe just some kids fooling around. ←Baseball Bugs What's up, Doc? carrots→ 05:51, 4 March 2010 (UTC)
 * ... But it's not deja vu if you've literally read the same thing twice! Deja vu is when you have (Or feel that you have) two memories of an event that you know only happened once! And I'm sure that this question hasn't only happened once. APL (talk) 05:57, 4 March 2010 (UTC)
 * In any case, there's a group of users that are asking similar questions, basically whether Star Trek is "real". ←Baseball Bugs What's up, Doc? carrots→ 06:02, 4 March 2010 (UTC)
 * An antimatter powerplant on the other hand would probably work great, the big problem is getting the fuel. Rather the biggest problem.  Isolating your fuel would also be difficult. Googlemeister (talk) 14:09, 4 March 2010 (UTC)