Wikipedia:Reference desk/Archives/Science/2007 September 8

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September 8[edit]

adrenal insufficiency[edit]

What are the signs and symptoms of adrenal insufficiency and how do you treat it? —Preceding unsigned comment added by 72.69.222.19 (talk) 02:03, 8 September 2007 (UTC)[reply]

If this is for yourself, you should see a doctor. If this is your med-school homework, a doctor should C you. --Sean 02:12, 8 September 2007 (UTC)[reply]
If this is med-school homework, please give up on your goal of becoming a doctor Nil Einne 15:42, 8 September 2007 (UTC)[reply]
That's a pretty ridiculous suggestion. See your talk page. --David Iberri (talk) 20:12, 8 September 2007 (UTC)[reply]
I was simply pointing out that a medical student, for that matter any student who is for whatever reason unable to do their own searches is not going to get very far... I would strongly suggest that such a student seek help and find out how to search for stuff themselves or alternatively perhaps being a student isn't their path in life. I admit I'm not an expert but I was a student not long ago and I can say from my experience if you're unable to search for something as simple as adrenal insufficiency you're going to have major problems as you progress Nil Einne 08:15, 9 September 2007 (UTC)[reply]
It depends on the etiology. See adrenal insufficiency for some details. --David Iberri (talk) 02:26, 8 September 2007 (UTC)[reply]
(ec) Ever noticed the search box on the left hand side of your screen? Typing adrenal insufficiency would direct you to Adrenal insufficiency the from there (box, top right) you will find plenty of links that will help you find the answers to your question. Rockpocket 02:27, 8 September 2007 (UTC)[reply]

Identifying slug like creature[edit]

This is a photo of a slug like creature taken in the Redwoods area of Northern California. Can anyone identify it (or point me to the relevant slug identifying desk)? Cheers. --Roisterer 05:19, 8 September 2007 (UTC)[reply]

What might it be?
I'm pretty sure it's a Pacific banana slug (Ariolimax columbianus). They can be huge! -- Flyguy649 talk contribs 05:22, 8 September 2007 (UTC)[reply]
Thanks. As it turns out, the Pacific Banana Slug has more than enough images anyway. I was hoping I had snapped an image of an extremely rare slug. --Roisterer 05:29, 8 September 2007 (UTC)[reply]
You can occasionally see a particularly large one supporting the University of California, Santa Cruz at sports events. Rockpocket 05:57, 8 September 2007 (UTC)[reply]
Your picture looks clearer than most of the pictures in the article, so it might be useful anyway. Skittle 11:24, 8 September 2007 (UTC)[reply]
yeah, I think it is clearer than the current images we have so I suggest you move it to a better name and use it in the infobox of the article. Jeltz talk 13:39, 8 September 2007 (UTC)[reply]
Yeah, they aren't rare, but they are much loved. As a child in Northern California they took us on field trips to the Redwoods and one of the "activities" was to kiss a banana slug. --24.147.86.187 12:30, 8 September 2007 (UTC)[reply]
Kiss them? Why? Do they secrete psychotropic substances? Who was running these field trips?--The Fat Man Who Never Came Back 14:52, 8 September 2007 (UTC)[reply]
What our anon friend fails to mention, I suspect, was that she was born in the late 50s and the Redwoods were in The Haight Rockpocket 08:11, 10 September 2007 (UTC)[reply]
Nice photo! I definitely encourage you to work it into article space somewhere. Also note that despite the name, these guys taste nothing like a banana. Friday (talk) 16:18, 10 September 2007 (UTC)[reply]
When the slime comes into contact with a moist surface, it produces an anasthetic which causes the membranes to go numb., according to the article. Lanfear's Bane 15:36, 14 September 2007 (UTC)[reply]

mobiles- radio access[edit]

Why do the mobiles can't access radio or F.M.stations without any headsets. If we try to do that..it always displays "connect an enhancement" or "insert an earphone"...but why this was so? Temuzion 11:06, 8 September 2007 (UTC)[reply]

The earphone cable acts as an antenna to pick up the radio signal I think — Matt Eason (Talk &#149; Contribs) 12:03, 8 September 2007 (UTC)[reply]
But why couldn't they just put an internal antenna in? --antilivedT | C | G 00:16, 9 September 2007 (UTC)[reply]
I don't know if the phones really work as an antenna. It is a good explanation, however. I just want to say that an antenna that works on the FM frequency range should have a length of about 1.5 m. That's why there isn't an internal FM antenna on the mobile devices. 84.91.226.18 22:31, 9 September 2007 (UTC)[reply]
This explanation is also nice...but you said it needs to be 1.5 mts length..if that length need not to be straight...then why can't they put it in a folded way in that phone? Temuzion 05:09, 10 September 2007 (UTC)[reply]
For a half-wave antenna you would need 1.5 metres long antenna for 100Mhz, but half-wave dipole is not the only type there is out there... --antilivedT | C | G 08:25, 10 September 2007 (UTC)[reply]

Brain IQ[edit]

Are their real real ways to increase brain IQ to a genius for example??if their is what are they —Preceding unsigned comment added by 212.107.116.246 (talk) 12:33, 8 September 2007 (UTC)[reply]

In theory, your IQ doesn't change through your life - in practice the definition of 'IQ' and the way it's tested is not perfect. But if you just want to know whether you can make yourself smarter - there are no short cuts. Read lots of books - study subjects that interest you - exercise your brain, do things that are hard. Writing for Wikipedia is a great way to do that. Research subjects - get to be expert in them - write articles about them. SteveBaker 14:15, 8 September 2007 (UTC)[reply]
You can certainly increase your IQ score by practising on books of IQ tests and books of lateral thinking questions and cryptic crosswords. Studying stuff like maths and logic will also help you to think more clearly. Whether this increases your actual intelligence is debatable.--Shantavira|feed me 15:15, 8 September 2007 (UTC)[reply]
Exactly. As I mentioned in an earlier question it's highly questionable how much merit IQ tests have since it's well established that you can increase your IQ score by practicising. If your definition of intelligence is "how well you perform in IQ tests" then by definition you are increasing your IQ. But this seems a pretty sillt definition to me even if it appears to be a definition commonly used by the media (effectively). However if you consider intelligence an inate ability which can't be increased then clearly all you've shown is that IQ tests are not an excellent measure of intelligence. From a academic standpoint, what intelligence is is a hotly debated topic. Clearly IQ tests are measuring something and it appears to be at least partially inate but as I've already mentioned is not completely. It does appear to be a predictor of how well people will perform at certain real world tasks. In any case, whether you it really makes sense to sum up 'intelligence' into one metric is a different issue altogether. Also whether you can truly seperate the inate from the learnt is another rather complicated issue. Considering things from a real world view you should first ask yourself what you want to achieve. If your goal is to get into MENSA then sure improving your IQ score may be useful. If your goal is to better yourself and perhaps improve your job prospects and/or eventual salary then you'll likely find there are more sensible ways to do this. Nil Einne 15:41, 8 September 2007 (UTC)[reply]
The apparent circularity in the definition of "IQ" is real and fairly widely acknowledged. (It is not just a media misconception.) In fact, none other than Alfred Binet (who invented the IQ test) was once asked what "IQ" was, and he answered, with an almost perfectly straight face, "It's what my test measures." —Steve Summit (talk) 15:50, 8 September 2007 (UTC)[reply]
Yes but note there's a big difference between IQ and intelligence. IQ is what the IQ test measures. IQ is supposed be a measure of intelligence too but how good it is, is an open question. As I mentioned there is big debate about what intelligence is but for many people it's an important thing. So there's a big difference in saying women on average score lower on IQ tests and saying women are less intelligent on average then men. The first appears to be mostly factual (the reasons are debated and as I mentioned earlier I've heard before the original IQ tests AFAIK had the medians for males and females separate so each was 100) the second is unproven and likely to be considered offensive. How useful the IQ is in general (whatever it measures) is another question altogether. The thing is the media often confuse the difference between IQ and intelligence even though these are very different concepts. Nil Einne 10:03, 9 September 2007 (UTC)[reply]
Agreed on all points. Anyone who equates "IQ" with "intelligence" is committing a rather grave intellectual sin. The test's inventor didn't equate the two, and nobody else should, either. —Steve Summit (talk) 13:06, 9 September 2007 (UTC)[reply]
Intelligence is a function of many things. Me, I'd say some of the important ones are:
  1. Memory. Intelligent people have a fantastic memory, and can readily remember old facts which bear on a current problem.
  2. Logical thinking. Intelligent people reject emotional arguments and guesswork, and insist on accurate, repeatable, scientifically-valid answers.
  3. Making connections. Intelligent people notice connections between seemingly-disparate facts and events, and build on these connections to form new knowledge.
  4. Seeing patterns. Intelligent people notice when a new problem is "just like" an old one, so that they can use the solution to the old problem to guide the solution of the new. (I put "just like" in quotes because sometimes the similarity can be startlingly oblique -- but it's there, and if you can see it, it helps.)
  5. Discipline. Intelligent people are driven in their search for truth. They're willing to work much harder at it, and at avoiding the fallacies and intellectual shortcuts which lead to false knowledge.
  6. Thirst for knowledge. Intelligent people love learning new things. Their brains suck them up automatically; they don't even necessarily have to work at it.
  7. Recognition of problems. Sometimes, the hardest part of solving a problem is just recognizing that it is a problem that's potentially amenable to solution, as opposed to something that's "just the way things are". Intelligent people look at everything and ask, "Does it have to be that way?"
  8. Heresy. Intelligent people are willing to question everything. They won't accept something just because that's the way you say it is; they reserve the right to rederive the result for themselves, and to reject it if they can't.
  9. Open-mindedness. Intelligent people are willing to think about anything and everything. They don't say "That's not my problem" or "Oh, I'm not interested in that."
Now, the nice thing is that some if not all of the things on that list can be learned, or at least practiced and improved. All you have to do is want to, and be willing to work at it. —Steve Summit (talk) 15:37, 8 September 2007 (UTC)[reply]
P.S. A great way to practice some of these skills -- and that doesn't even have to feel like work -- is by playing good games. (Where by "good games" I mean "those that aren't primarily or wholly games of chance".) For example, it seems to me that bridge would be an excellent mind-stimulation game. (I confess, though, that I've rarely actually played it myself, and that many people might find it uncomfortably like work. :-) ) —scs
If your diet is detrimental to your physical development, then that may affect your intelligence, so in that case improving it would likely increase your intelligence. Omega 3 (such as in fish oil) is a good example. Nowadays many people don't eat a lot of fish, including me, so I take fish oil pills. There is some evidence that people who had brain injury benefit from large doses of fish oil. But for a healthy person, something like one herring per week would be sufficient. Whether large amounts of fish oil would benefit a healthy person is being researched, but still highly debatable. It most certainly makes them stink, though. :) DirkvdM 17:58, 8 September 2007 (UTC)[reply]
In response to Steve's list, I'd say there are just two basic aspects of intelligence: memory and creativity (for lack of a better word). Logical thinking, making connections, seeing patterns, heresy and open mindedness are just different ways to express the latter (though it doesn't hurt to list them all to get the point through, because, like I said, I can't think of a good single word for it). Thirst for knowledge is just a result of having intelligence, not an aspect of it. And I don't see discipline as an aspect of intelligence, unless it is meant as a result of the thirst for knowledge. Recognition of problems, however, is a good one. I'm not sure about that. It's certainly a trait of intelligent people, but if it's an aspect of intelligence or a result of it I'm not sure. DirkvdM 18:05, 8 September 2007 (UTC)[reply]
What, you're seeing patterns in the list? A good sign! :-) —scs
Blush. DirkvdM 07:43, 9 September 2007 (UTC)[reply]
  • If you fill your brain with as many facts as you can, your creativity will have much smaller leaps to make between foot holds. Also, knowing many facts is often seen as intelligence by others, which has value in itself. So read a book. --Sean 19:32, 8 September 2007 (UTC)[reply]
That's some really bad advice, in my opinion. It used to be useful to know facts when there weren't a lot of books available nor the Internet, but nowadays there's no need for it. Only stupid people will see fact knowing as intelligence. I think it's best to think about things in which you're interested, talk with other people, and only read something if you're really curious, to satisfy yourself, not to be seen as intelligent by people who don't know what intelligence is. A.Z. 21:15, 8 September 2007 (UTC)[reply]
I didn't suggest learning things in order to be seen as intelligent, only that knowing a lot of things is seen as intelligent by many people. I respectfully disagree with your idea that the Internet has made being widely knowledgeable less useful. It's no good being in a situation that demands some insight and saying, "I could go Google this topic and then have something useful to say". Anyone could do that! --Sean 00:04, 9 September 2007 (UTC)[reply]
Yes, anyone can do that nowadays. Some centuries ago, we couldn't, so people who knew stuff that today Google knows were considered "intelligent". A.Z. 00:10, 9 September 2007 (UTC)[reply]
Be that as it may, there's a huge difference between knowing something, and knowing where to look it up.
I'm not saying that in many cases knowing where to look something up isn't sufficient -- we can't remember everything, so the ability to do research is a must. But if you're an expert in a field, you're not going to be able to make advances and do good work if you have to look something up every five minutes.
Consider a foreign language that you're knowledgeable of but not fluent in. If you try to read a book in that language, you either have to stop to look up unknown words multiple times per page, or you have to skim along, getting only a partial impression of whatever wonderful web of words and meaning the author has spun. Either way is less than optimum, and often quite unsatisfactory.
Or consider programing languages. In languages in which I'm expert, the limitation on how fast I can program is literally how fast I can type. But in an unfamiliar language, I'm constantly having to stop and scratch my head, or look up the name of a library function I think I need. —Steve Summit (talk) 00:56, 9 September 2007 (UTC)[reply]
Sean, a book? You mean one of those paper thingies? We're sitting on top of the biggest structured collection of information the world has ever seen and you recommend reading a book?? AZ, Google doesn't know anything. It's an index to sites that might (!) have useful info. But even those sites aren't themselves intelligent. Written info isn't intelligence, nor is it a substitute for it, it's an aid. In order to unleash your intelligence on info you first have to get it in your head. And the more info there is in there, the more connections you can make between all those facts, and that aids intelligence (as Sean pointed out). There's the two basic ingredients of intelligence again: knowledge/facts/memory and creativity/logic/patterndetection. And I wonder if even that distinction is valid. The method by which we reason is also the way we remember things. I've done a lot of thinking about this over the last two decades and I'm pretty convinced that there are some very simple rules that are applied at different levels and even to themselves, so that a small simple nucleus (apriori knowledge) can grow out to something very big and complex, provided it gets sufficient input and hardware to deal with it. DirkvdM 07:43, 9 September 2007 (UTC)[reply]
Why not a book? Being able to name 50 Pikachus and their characteristics may be useful and a sign of intelligence in some circles but personally and perhaps this is elitist of me I would say it's more useful to have knowledge of other stuff including a lot of stuff that is very or at least somewhat poorly covered in wikipedia like developing countries, science etc. Of course wikipedia may still be a starting point but you'd likely find you need to actually read some of the sources and recommended material eventually. I somehow don't think it's a good idea if your knowledge comes completely from wikipedia. But you know what they say, the best way to know your understand something is to try teaching/explaining it. We have the next best thing here. Once you've done your reading from the reliable source try writing/improving the article. Nil Einne 10:16, 9 September 2007 (UTC)[reply]
  • Books are reliable sources; Wikipedia is not. There are other reasons, but that in itself is enough. --Sean 12:06, 9 September 2007 (UTC)[reply]
No source is ever fully reliable. Take the bible, for example. :) It's true that on average they will be more reliable than stuff on the Internet, but you always have to take that into account, whatever you read. Only scientific publications can be taken to be largely reliable, but the problem with those is that they are unintelligible to most people. Wikipedia is usually more legible than them but more reliable than most other 'popular' sources on paper, because it is cross-checked by others. Anyway, I was half jesting. :) DirkvdM 18:17, 10 September 2007 (UTC)[reply]
IQ is (as I said before) poorly defined - but IQ testers work hard to eliminate memory as an aspect of what they are testing. So I don't believe that the ability to remember all the characteristics of all of the Pokemon is a measure of IQ - nor do I believe that remembering all of the characteristics of all of the elements in the periodic table is a measure of IQ - nor any other large body of raw data. However, memory aids IQ in getting use through life and if you are a chemist, you'll be able to apply your IQ more efficiently if you memorise the periodic table than if you have to continually look things up. Memorising all of the Pokemon is an interesting curiosity and makes a great party trick - but beyond that, it's fairly pointless. The reason I recommend reading widely is because the act of being presented with a wide variety of ideas improves the way you connect up and understand knowledge. Cross-connections between disciplines is essential here. Becoming an expert in one very narrow field is not reflective of general IQ. There are plenty of examples of savants who have memorised things like the results of every baseball game in history - yet who have no interest in or understanding of the sport itself. Memory and IQ are both necessary - but they are unrelated skills. I have made a habit of reading three random Wikipedia articles every night before going to bed. I don't remember much of any of them - but the cross-connections of ideas are important. SteveBaker 16:24, 9 September 2007 (UTC)[reply]
Pokemon? I thought that was a Disney character (an Indian girl, I believe). The things I learn here. Now what might I cross-connect that with? :) DirkvdM 18:25, 10 September 2007 (UTC)[reply]
I mostly cross-connect it with a major argument with my kid about the merits of spending $125 on a 2"x3" piece of cardboard with some kind of a dragon printed on it. SteveBaker 19:22, 10 September 2007 (UTC)[reply]

Heaty food?[edit]

Hi everyone, I was just wondering what people mean when they say "don't eat too much heaty food"? —Preceding unsigned comment added by 116.14.180.26 (talk) 15:16, 8 September 2007 (UTC)[reply]

Heaty foods? Are you Cantonese by any chance. Or at least Chinese? Personally I've never really understood the concept much. Durian is supposedly a heaty fruit and you're not supposed to eat too much and counteract this by eating cooling fruit like Mangosteen. But other then that I don't really know the details much. But I can say from a scientific standpoint point it's mostly bull Nil Einne 15:27, 8 September 2007 (UTC)[reply]
It's probably rooted in pseudoscientific belief such as the theory of four humors. We also have a separate article called Humorism which discusses the "hot" and "cold" and "humid" principles. Of course, this has been wildly discredited as our knowledge of true anatomy increased. Nimur 16:39, 8 September 2007 (UTC)[reply]
I've never heard the word "heaty". —Tamfang 16:55, 8 September 2007 (UTC)[reply]
I hadn't either and at first I thought Nil Einne was joking or maybe teasing the OP about a misspelling, but a quick google search suggests that this is, in fact, the right concept. —Steve Summit (talk) 18:14, 8 September 2007 (UTC)[reply]
Basically all fried, oily stuff (chips, even instant noodles), lychee, durian, etc. are considered "heaty", which you will get sore throat, mouth ulcers and worsens acne. Whether you believe it or not it's still good to not be eating too much fatty fried stuff. --antilivedT | C | G 00:11, 9 September 2007 (UTC)[reply]
While it may have some basis in fact (as do many cultural norms), it's way too simplistic to be of any use IMHO. For example putting durian and lychee in the same category as chips is frankly a little dumb. For that matter according to this [1] (not a reliable source I admit) butter is a cooling food... Indeed according to durian it's fat content is about 5.3%. High for a fruit I guess but I you'd have to eat a lot for it to be a big concern IMHO. The potassium content is likely to be a far greater concern from what I can tell yet foods with a high potassium content are supposed cooling! Also in terms of the ill effects of eating too much fatty food I've never even heard of it causing Oral ulcer & sore throats and the acne link remains unproven. Obviously poor nutrition in general is a bad thing for your health but I would have to say I don't find the list of ill effects of heaty foods particularl convincing either. Also I don't see any reason why you would have to eat mangonsteen (cooling food) to counteract the ill effects of heaty durian. Sure a balanced diet is good and it may be better to eat mangosteen then durian so if it reduces the amount of durian you eat I guess that's good but it's not counteracting the ill effects. So thats why all in all, I feel the concept is meaningless from a scientific standpoint. Nil Einne 08:44, 9 September 2007 (UTC)[reply]
I don't get much of an effect from durian but I dare you to eat a kg of FRESH lychee and see what happens... --antilivedT | C | G 08:23, 10 September 2007 (UTC)[reply]
I probably should have explained better for the benefit of those who never heard of the concept before. Basically I believe it's heaty because it's supposed to make your body (or spirit?) 'heat' up. The opposite is 'cooling' food. I've mostly heard of it in relation to fruit but as Antilived mentioned it's applied to all food I believe. Simplisticly that's why your supposed to eat cooling foods to counteract the ill effects of heat food I believe although too much heaty food in general is also considered bad. Also I may have been wrong about the Cantonese bit. I'd thought the concept was primarily a Cantonese one but it appears it may not be restricted to them. I forgot to mention from my searches e.g. [2], http://www.benefits-of-honey.com/heaty.html (link is on the spam blacklist) and other sources, it may have something to do with the Yin and Yang concept Nil Einne 09:06, 9 September 2007 (UTC)[reply]

Sunrise vs. Sunset[edit]

I always wondered why sunrise and sunset don't look the same. During sunrise, the sun is significantly brighter - I can't look at the sun during sunrise, but during sunset, it's a much deeper and less blinding red.

Not a single person I asked could give me a convincing answer on the subject. Maybe you can avail me? 82.166.190.58 15:55, 8 September 2007 (UTC)[reply]

I don't think I've ever noticed the phenomenon, but maybe what you're experiencing has to do with what your eyes have adjusted to. At dawn your eyes have adjusted to the darkness, so bright things seem that much brighter. At dusk, your eyes have gotten used to the bright blue sky and so aren't bothered at all by the dim red sun. Matt Deres 16:11, 8 September 2007 (UTC)[reply]
You could try to get photometric data to check whether there is any absolute difference in brightness for a given sun position. Nimur 16:36, 8 September 2007 (UTC)[reply]
There's more dust in the air in daytime. —Tamfang 16:54, 8 September 2007 (UTC)[reply]
Edit conflict. Especially if you live in an urban area pollution levels will typically be far higher at the end of the day after a day's traffic and other pollution, compared to the relatively clear air at dawn after a night's inactivity. That you in fact identify the sun as being a 'deeper and less blinding red' at sunset suggests there may be a greater effect from the particulate matter in the air scattering the sunlight more. See sunset which discusses this, also scattering and Mie theory. --jjron 17:08, 8 September 2007 (UTC)[reply]
Is it useful to have separate articles for sunset and sunrise? A.Z. 17:58, 8 September 2007 (UTC)[reply]
You mean sunrise and sunset? Or are you suggesting they should be merged? DirkvdM 18:09, 8 September 2007 (UTC)[reply]
Culturally and philosophically they are very different. I don’t see why they should be merged. --S.dedalus 05:42, 11 September 2007 (UTC)[reply]
In many places the sky tends to be clear in the morning and cloudier later in the say, presumably because the sunlight promotes evaporation of water which rises as vapor to an altitude where it re-condenses. A sunrise in a clear sky will be brighter than a sunset with clouds. --Anonymous, 21:47 UTC, September 8, 2007.
Say, but I was just about to say the opposite: in many places, there are regularly early morning fogs, which always burn off by the end of the day... —Steve Summit (talk) 21:56, 8 September 2007 (UTC)[reply]
I suppose that morning fog is close to the ground and will therefore have less effect on the incoming sunlight than clouds up in the sky. Except maybe when the sun is only just over the horizon and visible (ie no buildings or hills), which is often not the case. DirkvdM 08:00, 9 September 2007 (UTC)[reply]
There would also be less light pollution at dawn I guess Nil Einne 09:42, 9 September 2007 (UTC)[reply]

General Relativity[edit]

Hi, I'm german, so please excuse my poor english. I have a question concerning covariant derivatives: Consider a real-valued function f(x,x') in two arguments which are both from some manifold M. I want to take first covariant derivatives with respect to both arguments and I wonder if they reduce to partial derivatives like

.

The primed derivatives mark derivatives w.r.t. x'. I know that this formula would be wrong if I took both derivatives w.r.t. the same argument, because the first derivative would lead to a (co)vector quantity, which would demand the use of christoffel symbols for the second derivative. But I think in my case the quantity should stay scalar in x even after derivative w.r.t. x', because this would certainly be the case, if I considered x and x' being from different manifolds. Am I right? -- 88.76.244.169 19:07, 8 September 2007 (UTC)[reply]

Poor English? Wow, if I could handle covariant derivatives as well as you handle English I would be able to help you.Richard Avery 07:51, 9 September 2007 (UTC)[reply]
I believe you're correct. --Reuben 08:10, 9 September 2007 (UTC)[reply]

Light as a wave[edit]

Is there a known reason that, in one way of looking at light, it travels as a wave, or is that just one of the properties of the universe that is just because it is? 72.128.74.159 21:42, 8 September 2007 (UTC)[reply]

Whoops! Forgot to sign in. Imaninjapiratetalk to me 21:43, 8 September 2007 (UTC)[reply]
You'll need someone a bit better versed in quantum mechanics to say whether there is a reason (though the question might actually be more metaphysics than physics), but light always travels as a wave. The photon only acts as a "particle" when it actually interacts with another particle (such as hitting something or being absorbed by something as a quanta of energy). --SB_Johnny | PA! 23:33, 8 September 2007 (UTC)[reply]
Well, the good old classical explanation is that it is entirely the result of charge interacting through the coulomb force. Adding relativity to the equation, along with some other assumptions, yields Maxwell's laws (not that that's how they were originally derived). Maxwell's laws predict the existence of electromagnetic waves essentially as a mere consequence the laws themselves. But note that electromagnetic waves are force fields that possess wavelike characteristics, and are not the same as quantum mechanical wave-particles. Someguy1221 00:30, 9 September 2007 (UTC)[reply]
Alternatively, we might say that light is neither particle nor wave; light is just light. When we try to describe what it is doing, we find that it often behaves like a wave (which is a mathematical and conceptual construction defined by certain characteristics - see wave). Other times, it behaves like a particle - that is, a distinct entity with a specific quantity of momentum and energy and a definite location and a "trajectory" of motion. Whatever the actual property of the universe, we find that the wave model is a suitable description while light is propagating (traveling); and the particle description is a good approximation to what happens when the light interacts (hits something). Maybe both are right! Maybe both are wrong! It doesn't matter - we can make correct quantitative predictions about the behavior of light by using these descriptions in appropriate ways. Nimur 05:02, 9 September 2007 (UTC)[reply]

Bicuspid valve[edit]

Our article on Edith Bowman claims "Bowman was diagnosed with a bicuspid heart valve". Presumably this is a mistake (surely everyone has bicuspid valves), but every source I can find also simply says "bicuspid valve" (all use the same quote, apparently from [3]). What does bicuspid mean when used to mean some sort of defect - is it a defect with the bicuspid, or a bicuspid valve where she should have some other sort of valve? Laïka 22:11, 8 September 2007 (UTC)[reply]

It sounds like she misspoke, and meant to say "bicuspid valve problem", or some such. Another source says she has a heart murmur, so perhaps it's a mitral valve prolapse. But Ms. Bowman, if you're reading this, please don't take it as medical advice! --Sean 00:13, 9 September 2007 (UTC)[reply]
There's no reason to assume that a heart murmur indicates a mitral valve problem. In fact, the most common valve problems are mitral and aortic stenosis, not mitral insufficiency (as suggested by MVP). A bicuspid valve could refer to a bicuspid aortic valve, whose prevalence is approximately 1.4% wordlwide. --David Iberri (talk) 05:08, 9 September 2007 (UTC)[reply]

hydrocodone vs.oxycodone[edit]

what is the diference between hydrocodone and oxycodone? —Preceding unsigned comment added by Twdyer (talkcontribs) 22:14, 8 September 2007 (UTC)[reply]

Have you looked at our articles on hydrocodone and oxycodone? Splintercellguy 22:48, 8 September 2007 (UTC)[reply]
Looks to be an OH group Algebraist 23:26, 8 September 2007 (UTC)[reply]
Just browsing the hydrocodone article, there is a completely unnecessary bit of information detailing how one might extract hydrocodone from the Tylenol it is commonly paired with. It suggests that some patients with liver problems extract the hydrocodone in pure form since acetaminophen is metabolized by the liver. This would never be requested of a patient. A quick glance at my Pocket Pharmacopoeia shows me that there would a)be several alternatives were this really a problem and b)hydrocodone is also metabolized by the liver... So, the information on how to separate the two drugs seems to be of use only to someone who wants to separate the two for another reason. I don't think it should be available in such an obvious place.
Mrdeath5493 05:56, 10 September 2007 (UTC)[reply]
Makes it sound like article has undue weight on such a rare legit action or else is missing some cites for what sounds like WP:OR. Along with UNDUE, it's got way too much detail in light of Wikipedia is not a how-to manual, especially for something that could be taken as health advice. Let's take this to the Talk:Hydrocodone page, which has previously discussed this section of the article. DMacks 06:03, 10 September 2007 (UTC)[reply]
It's a drug abusers "how to". Hydrocodone paired with acetominophen is not as regulated (class III vs. class II in the U.S.) and is therefore easier to obtain. Too much aceptominpohen will cause vomiting and other unpleasantness and therefore reduce it's effectiveness to get high. This is why it has a different classification for the DEA. it's illegal and dangerous to do this so it should be removed. --DHeyward 06:10, 10 September 2007 (UTC)[reply]
I'm not sure how these things usually go on Wikipedia, but that particular snippet of information should be excised. Should I just do it?
Mrdeath5493 03:07, 11 September 2007 (UTC)[reply]
I did but it was reverted. I removed it again as it isn't reliably sourced. --DHeyward 04:03, 11 September 2007 (UTC)[reply]