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October 28

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Alcohol consumption strange side-effects

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Hello, all!

I have volunteered and worked with person(s) who have various severities of alcoholism, from merely excessive to outright insane levels of consumption.

I was curious if someone could explain some of the stranger side effects I have witnessed:

1. Brightening of colors -- White colors becoming blinding, yellow becomes white, confusion of black/blue or yellow/green, etc.

2. Having nonexistant conversations -- with people whom are not speaking, or, thinking there is someone in the room speaking to them when there is not. Not a delusion - the person, even when confronted, thinks there is someone talking to them.

3. The ability to drink a large amount of alcohol (1/5 of vodka, etc.), and, in a relatively short amount of time (1 hr.), the person is relatively sober and able to pass a breathalyzer test (.08 BAC). I was under the impression that this is physically/anatomically impossible.

4. Blindness that fades in and out, however, the person remains able to speak clearly without slurred speech and has generally unaffected motor skills.

5. Phantom-limb type symptoms (w/ people who have lost limbs), but only when heavily inebriated.

Thanks, --70.156.13.172 (talk) 03:58, 28 October 2008 (UTC)[reply]

3. This is not physically impossible for people who regularly consume large amounts of alcohol. Their bodies will eventually become adapted to higher than normal BAC levels and will metabolize alcohol faster, allowing them to consume larger amounts without actually intoxicating themselves. Unfortunately, in order to achieve intoxication, they must drink larger and larger amounts of alcohol, which really damages their livers.CalamusFortis 04:09, 28 October 2008 (UTC)[reply]


Also - (for #3) it takes a while for the alcohol in the stomach to make it into the blood stream - and from there into the lungs so it'll show up on the breath tester. Over a very short period, I guess it's just about possible.
For all of the other symptoms: Cell membranes can't block Ethanol - so it can attack any cell in the body. Hence, a huge range of side-effects are possible. Heavy drinkers that have varieties of liver problems will suffer another huge range of symptoms from whatever toxins are in their bodies that a healthy person could metabolise without side-effects - but their broken livers are unable to get rid of fast enough. So the consequences for heavy drinkers go beyond the primary effects of the alcohol and into secondary effects that could be due to medications or other things in their diet that would ordinarily be no problem for a healthy person.
But anyone who's ever had more than a couple of drinks in their lives knows that alcohol screws with your brain...once someones brain is screwed - you shouldn't be at all surprised at all of the blindness, bizarre vision issues, phantom limb stuff and auditory hallucinations. It's like you're taking this very large, delicate and super-sophisticated computer and smashing random bits of it with a hammer...the result is entirely predictable...the computer starts to break down. Precisely HOW it breaks down is a lot less predictable. Brains are massively parallel machines so they don't have a single point of failure. So instead of 'crashing' like your PC probably does when you smash it with a hammer - the brain merely generates incorrect results. Since the ethanol is attacking the entire brain at once - it's impossible to predict which bits are going to break first - or what the consequences will be. So for some people - the vision system gets hit - for others it's the nervous system - for others it's memory or hallucinations or insomnia or hypersomnia. Once the brain is broken somewhere at random, almost anything is possible. SteveBaker (talk) 04:29, 28 October 2008 (UTC)[reply]

Alcohol withdrawal or the rarer Korsakoff's psychosis could explain these symptoms. Axl ¤ [Talk] 07:38, 28 October 2008 (UTC)[reply]

If time is Infinite...

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..and there is no irreversible equilibrium state in which the properties of all matter and energy are either fixed or in a repeating loop, then logic suggests that any event that could possibly happen will happen an infinite number of times.

Discuss.NByz (talk) 06:55, 28 October 2008 (UTC)[reply]

(edit conflict) It seems to me the phrase "any event that could possibly happen" is ambiguous. Do you intend this just to mean it is possible to imagine an event happening, or does it mean something stronger than that?
For example, it is possible to imagine a streetcar plunging into the Grand Canyon. However, unless there are streetcar tracks very close to the rim, I suspect it won't happen.
I think the statement as it stands is incorrect, that a lot more things "could possibly happen" than actually do happen. CBHA (talk) 04:40, 28 October 2008 (UTC) (More philosophy than science, ISTM.)
I highly suggest that we don't address this question here. It should be addressed on the science reference desk. Magog the Ogre (talk) 04:45, 28 October 2008 (UTC)
I'll give it a try out there. I guess the purpose of the question is to make you test just how big your minds concept of "infinity" is. Even though there is no logical reason that a streetcar's tracks would lead into a 'Grand Canyon', the very concept of "dividing infinity", to me, always meant that regardless of how small the chance of something is (like for example, atoms with identical properties reforming an infinite number of exact replicas of earth) will happen an infinite number of times in the universe I described.NByz (talk) 06:52, 28 October 2008 (UTC)
I moved this from the misc. desk. I am interested in articles about this type of thinking. Or people shooting it down with better logic.NByz (talk) 06:56, 28 October 2008 (UTC)[reply]

Even in a finite time period in a finite region of space, any event that could possibly happen...could happen. But that says nothing of what will happen. You run into an issue of our own universe. Depending on the ultimate fate of the Universe, and assuming the universe is finite in extent, then not everything may happen. If the universe hits an abrupt end somewhere, then time is finite, and not everything will happen. If the universe is inifinite but suffers heat death or explosive expansion, then the probability of certain events will shrink even closer to zero as time proceeds, and so the infinite time integral of a certain event's probability may still be close to zero. But under certain scenarios, including that the universe is infinite in extent, then yes, it would certainly seem the case that anything that can happen, since it can happen anywhere with some probability, has a probability of 1 of happening somewhere. Your chance of witnessing it may still be close to 0 if it is something dramatically unlikely, like a grand piano appearing out of thin air. For further reading, you may be interested in boltzmann brain and quantum immortality, the latter being on a supposed consquence of the (perhaps) infinitely many, and completely encompassing many-worlds. Someguy1221 (talk) 07:06, 28 October 2008 (UTC)[reply]

Those were cool articles. I guess we'd have to alter some of the assumptions about the universe in order to suggest my conclusion. I'm thinking that this hypothetical universe had no tendency towards entropy, and no eventual state of repetition or 'boredom'; there is always the potential for something to change (but not in some repeating loop or in some way that it has before), but not to the point where each 'state' of the universe was stochastic. Doesn't the fact that 1) something will change between this state of the universe and the next, 2) that the change won't be repetitive (everything isn't just clumping up, or spreading out) and 3) time is infinite mean that, no matter how many units of matter and energy exist in the universe, they will eventually be arranged in every conceivable way?NByz (talk) 08:00, 28 October 2008 (UTC)[reply]
Every way that is reachable from the initial state under the laws of physics, maybe. It may be possible that there are two states which can't be reached from each other without violating the laws of physics - a mathematician would say that the action of the laws of physics on the state of the universe isn't transitive. Of course, those assumptions don't fit with our universe, so this discussion is entirely academic. --Tango (talk) 11:44, 28 October 2008 (UTC)[reply]

See Poincaré recurrence theorem. I think the real world violates the assumptions of the theorem, though. -- BenRG (talk) 12:53, 28 October 2008 (UTC)[reply]


Even if time is infinite - it's still likely that it will settle into an eventual steady-state after which no further change will ever happen again. So in the case of the streetcar plunging into the grand canyon - it plunges once, smashes into a million pieces and then stays like that until the Earth is destroyed, the Sun fizzles out, the galaxy collapses into a black hole, the progress of the expansion of space and the demands of entropy cause everything to turn into a uniform, cold sea of particles. That state could then persist off into the infinite future with no possibility of new earths and new streetcars ever being formed, however long you wait. That would imply that we were in the cosmologically brief period between the big bang and the infinite, boring nothingness - and the number of streetcars falling into grand canyons could be completely finite - even utterly unique. Entropy is a harsh mistress.
However, if space is infinite, then it can also be fairly similar everywhere - and in THAT case, every event in every possible variation will happen an infinite number of times as out OP suspects - until the universe changes (due to entropy) into a state where that event is no longer supportable anywhere. SteveBaker (talk) 12:56, 28 October 2008 (UTC)[reply]
It also matters what you mean by "infinite". There are lots of kinds of "infinity". For example, the integers is an infinite set. So aren't the numbers between 1 and 2. However, one is a countable infinity, which allows progress towards the infinite "end". I can get farther along that number line, and can move between defined points on it in a meaningful way, even though the line is a defined infinity. There are also an infinite number of numbers between 1 and 2, and if one were to scrupulously define them all, it would be impossible to make progress. You can't even get to the next 0.1 or 0.01 or 0.001 because there are always an infinite number of finer divisions you can make. This is still infinity, but its not a countable infinity. The problem arises when the two types of infinity are conflated. Tbe classic example of this is Zeno's paradox, which states that motion is impossible because there are always an infinite number of divisions one has to move through to get anywhere, and each of those divisions should take some measureable time to pass through. There seems to be some very "Zeno-like" paradoxes going on in this discussion, and it's why its not getting anywhere. --Jayron32.talk.contribs 13:16, 28 October 2008 (UTC)[reply]
What you are saying is true - there are indeed many flavors of infinity - but here we're talking specifically of infinite time or infinite space (or both) - and those are countably infinite in the same way that there are infinite numbers of integers. To express it your way, travelling through space or the progression of time is "progress towards the infinite 'end'" - not the infinite subdivision of a finite bound. Given that this is all we're interested in - I don't see the relevance of your comment and the discussion is working out just fine.
As for Zeno's paradox - it doesn't seem at all paradoxical to me - the finer you slice the distance between Achilles and the tortoise - the smaller the time interval required to cross it. As soon as you slice the distance Achilles has to cross into infinitely many pieces - you reduce the time taken to cross each piece to 1/infinity - which means that you wind up with infinity/infinity as the time it takes to get there...but infinity/infinity is mathematically undefined - it's certainly not necessarily infinite - and in this case, it's most definitely not infinite. Since you can't evaluate that expression - you can't say that Achilles can never catch the tortoise - nor that he can. All you've done is come up with a bizarre formulation for the math that simply isn't the right way to solve the problem. You can take any perfectly sensible question ("What is 2+2?") and screw with the math to come up with a variation that involves various infinities that you can't solve. Is that paradoxical or just the results of the ravings of someone who doesn't understand much math? "What is 2+2?" Well, that's just 2+(2/2 + 2/2) which is just 2+((2/4+2/4)+(2/4+2/4)) which is just 2+(((2/8+....+2/8)))...which I can carry on subdividing into an infinite number of terms. Then I can argue that since we have to add up an infinite number of non-zero terms - the value of 2+2 is infinite...well, that's flat out not true - you have to add up an infinite number of terms EACH OF WHICH is 1/infinity...so you can't solve "What is 2+2?" this way. There are an infinite number of ways I can fail to solve that. x=2+2 ...hmmm...suppose I add infinity to both sides of the equation x+infinity=2+2+infinity=infinity...oh - darn - I can't solve that...therefore there is an exciting paradox that people should still be talking about thousands of years from now!?! It's a bloody stupid argument - yet it's identical to the Zeno "paradox". Zeno's paradox confuses philosophers - but then they are easily confused. Mathematicians and scientists just say "Well - that was a bloody stupid way to calculate when Achilles will catch the tortoise - let's just use the normal laws of motion - express Achilles' position as (velocity x time) - express the tortoise's position the same way - then we have two equations and two unknowns - which we can easily solve to get a perfectly reasonable, finite, time. Ergo the philosphers are wrong - which is no surprise because they are all a pretty useless bunch. Where is this paradox? Philosophers are a waste of space - fuzzy thinking turned into an art form!
SteveBaker (talk) 13:59, 28 October 2008 (UTC)[reply]
A bit unfair, Steve. We have the benefit of twenty-four centuries of work after Zeno, some of it arguably motivated specifically by him. No, Zeno's paradoxes are not particularly paradoxical, once you understand the real numbers, but they weren't really understood until the work of Dedekind and Cauchy and Weierstrass, less than two hundred years ago. Zeno's arguments do ably refute certain views of space, time, and the infinite, that might have been reasonable to hold at the time.
This is what philosophical paradoxes do best; they're not for explaining around the lava lamp so people can say "heavy, man"; they're for showing why certain otherwise reasonable positions have problems. Another good example is the Russell paradox, which lots of people take the wrong message from. The right lesson is that one has to distinguish between the extensional or combinatorial notion of set from the intensional notion of class (or extension of a definable property). That's what we do, these days, working in the von Neumann universe, but this was not clear even to Georg Cantor, though some of his writings can be read, after the fact, as prefiguring it. --Trovatore (talk) 08:50, 29 October 2008 (UTC)[reply]
Russell's paradox is not quite the same thing. Firstly, Russell was a mathematician AND a logician AND a philosopher. I'd argue that he didn't have his philosopher's hat on on the day he came up with the paradox - however, that's a separate matter. Secondly - this paradox is broadly the same as the Barber's paradox (which some suggest Russell invented in order to explain his set-theory paradox to the layman). These non-mathematical versions of the paradox are pretty easy to dismiss. The simplest solution is just that the statement of the paradox is wrong. "Everything I say is a lie" is simply not true...some things I say are lies, some things aren't - this happens to be one of the ones that's a lie. So it's hard to see a paradox in a statement that's just obviously false to begin with. All that happened was that the person stating the paradox said something which isn't true - and forced it upon us by stating it as an axiom in the framing of the question. It's the same deal with the barber who "shaves only those who does not shave themselves"...NO HE DOESN'T because that's simply impossible...we know that he shaves at least one person who shaves himself...so we can prove that the question itself is wrong - and therefore no answer is required of us. All you've done there is the logical equivalent of saying "It is axiomatic that 0=1 ... oh wow! Look what bizarre things just happened to all of my logic."...well DUH...if you make an axiom out of something nonsensical then you're bound to wind up with a nonsensical answer! So the existence of a "set of all sets that do not contain themselves" cannot be axiomatic in any self-consistent system - and you certainly can't derive a proof of the existence of such a set because it clearly can't exist in any halfway reasonable logical system. That's not exactly a paradox - it's a choice of axiom that doesn't match the way the real universe works and therefore produces counter-intuitive results. The cleanest take on this self-referential paradox issue is Godel's incompleteness theorem. It assures us that we can't have 100% self-consistent logical systems with sufficient complexity to do interesting math - and it does it without introducing new axioms. So the INTERESTING part of all this (the fundamental incompleteness of all sophisticated logical systems) is most definitely something that springs from mathematics - not from philosophy's "paradoxes" which are generally quite easy to dismiss using a small amount of clear thinking. SteveBaker (talk) 21:12, 29 October 2008 (UTC)[reply]
I'm afraid you're missing the point a little bit, probably because you don't know the history of the problem. What happened was that Gottlob Frege had proposed a system that he wanted to use to reduce mathematics to logic alone, based (he thought) on Cantor's set theory (though later writers such as Wang Hao have argued that Frege got Cantor wrong). Frege's system (which by the way was completely formalized, not "naive" in the sense that is sometimes suggested) identified sets (collections of objects) with extensions of (presumably definable) properties, and proposed that for every definable property, there was a set that was its extension. He certainly did not propose as an axiom that there was a set of all sets not containing themselves; that was simply a consequence.
It was a reasonable thing to try at the time. You're right, of course, that it was wrong. But it wasn't obvious that it was wrong. It took the paradox to show it.
One last aside — the bit about Gödel isn't quite right. It's perfectly possible to have "100% self-consistent logical systems" that do interesting math, and (we believe) we do have them. It's just that (subject to some technical stipulations) they'll never be able to settle all questions that you might ask. Therefore mathematical truth cannot be identified with provability. --Trovatore (talk) 21:47, 29 October 2008 (UTC)[reply]
Nice Post! I guess, in summary, I had to make too many unrealistic assumptions above to avoid an eventual "steady state", or to include infinite random fluctuations in the universe. It was meant to make you really think about how "big infinity is" and I think (after reading your post, especially!) that the concepts of "big" and "counting" can never really apply to ideas like this (in my hypothetical universe). Frankly, I've always felt that the whole concept of "discreteness" was a human illusion derived from the way we've developed problem-solving skills over our formative generations.NByz (talk) 18:29, 28 October 2008 (UTC)[reply]
The cause of the paradox is the assumption that doing an infinite number of tasks is impossible. However, there is absolutely no reason to make that assumption, philosophers like to make things up without any regard for whether they actually fit observation - as you say, they are a waste of space. --Tango (talk) 15:06, 28 October 2008 (UTC)[reply]

"Even if time is infinite - it's still likely that it will settle into an eventual steady-state after which no further change will ever happen again." — Steve Baker

If no change occurs, then "time" has ended. Axl ¤ [Talk] 15:31, 28 October 2008 (UTC)[reply]
No large scale change. There are likely to still be individual particles and photons moving around, but on the whole nothing will be changing. --Tango (talk) 16:18, 28 October 2008 (UTC)[reply]
Well - if you take that view - then the OP is correct. Even if there is hardly any motion left - if there is just SOME motion left then eventually (and we have infinite time) an extraordinary coincidence will result in an entire galaxy just like ours forming by sheer unlikely statistical luck - and the street car can crash into the grand canyon again (although it may be painted a slightly different shade of red this time around). Infinity leaves plenty of time for that to happen - however unlikely it is. For what I said to be true (and I still believe it), there has to be a time in the FINITE future when literally the last erg of energy is gone from the entire universe. That's a reasonable assumption because entropy drives things relentlessly in that direction. If Axl chooses to characterise that as time 'ending' or 'stopping' - then I guess that's a position one could take - but I don't see why you can't see it as time continuing along but with no change to measure its passage. However, since we can reasonably assume that the universe is spatially infinite - then the streetcar will smash into the grand canyon an infinite number of times while my finger was pushing down on the last period in this sentence. SteveBaker (talk) 18:26, 29 October 2008 (UTC)[reply]

If an event takes place at a certain time and place and if there is no repeating loop (of time), then each event can only occur once, I think.... 143.117.157.61 (talk) 12:00, 3 November 2008 (UTC)[reply]

Simplest oscillating reaction?

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Just looking for the cheapest way to set up an oscillating reaction for part of my halloween costume. The only one I know of is the Briggs-Rauscher, which is pretty, but expensive to make.

Anyone know any others that are easier to slap together? Also, how do I tell exactly how long such a concoction will oscillate for? —Preceding unsigned comment added by 66.158.193.46 (talk) 09:04, 28 October 2008 (UTC)[reply]

Though I think it probably not very practical, I would think the Halloween Reaction would be the most seasonal. We have articles on Briggs-Rauscher reaction, Belousov-Zhabotinsky reaction, Bray-Liebhafsky reaction, and the Iodine clock reaction as well. (They probably should have their own WP:Category).- Nunh-huh 11:07, 28 October 2008 (UTC)[reply]

Fidgetting and calories

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I'm a fidgeter. I seem incapable of sitting still, i'm always bouncing my legs or fiddling with things with my hands, tapping stuff, reposition myself etc. etc. (i know i'm a joy to be near). I'm also slim, naturally slim, and naturally quite fit. Question: How much calories does 'fidgetting' burn. Is it very little or would it be enough to say, i dunno, account for eating a bag of crisps or a chocolate bar? Also whenever i do stuff I do it 'quickly', be it going to the kitchen to get a drink, walking, typing, whatever, is that also likely to increase calorie consumption V someone who does these things more slowly? (Hope not too stupid a question) 194.221.133.226 (talk) 11:45, 28 October 2008 (UTC)[reply]

I don't think fidgeting affects calorie consumption in a major way. Muscles just don't burn calories at all that high a rate unless they are engaged in real activity. Speed of activity can change calorie consumption—a slow walk does not burn as much as a brisk walk. (ergo "power walking"). --98.217.8.46 (talk) 12:00, 28 October 2008 (UTC)[reply]
I'd call 16 pounds in 8 weeks a major difference. Or how about 30 pounds per year? jeffjon (talk) 12:41, 28 October 2008 (UTC)[reply]
The OP was asking how many calories are burnt fidgeting, not how much weight can be lost by it. They are different things. —Cyclonenim (talk · contribs · email) 12:50, 28 October 2008 (UTC)[reply]
1 pound of body fat is equivalent to about 3500 stored calories. TenOfAllTrades(talk) 13:51, 28 October 2008 (UTC)[reply]
You can run for a mile on the energy from one sugar cube. This is very depressing and seriously discourages me from doing enough exercise. SteveBaker (talk) 18:16, 29 October 2008 (UTC)[reply]
???? According to [1] there are 25 calories in a sugar cube. According to [2] running a mile uses 100-125 calories depending on your sex and weight. That's 4-5 times the energy of a sugar cube. Exxolon (talk) 20:37, 29 October 2008 (UTC)[reply]
Perhaps there is a correlation between leptin resistance (and being overweight) and activity levels. Mentioned offhand here: [3] 205.206.170.1 (talk) 21:29, 29 October 2008 (UTC)[reply]

Are there any planned missions to put a satellite around the moon with the resolution great enough to see the Apollo landers?

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Are there any planned missions to put a satellite around the moon with enough resolution to see the Apollo landers? Just wondering how soon we can finally put those Apollo hoax conspiracy theories to rest. 12.10.248.51 (talk) 17:03, 28 October 2008 (UTC)[reply]

From Lunar Reconnaissance Orbiter: "...will fly several times over the historic Apollo lunar landing sites, with the camera's high resolution, the lunar rovers and Lunar Module descent stages and their respective shadows will be clearly visible". Gandalf61 (talk) 17:10, 28 October 2008 (UTC)[reply]
Awesome. Thanks! 12.10.248.51 (talk) 17:21, 28 October 2008 (UTC)[reply]
See also the Indian craft, Chandrayaan, recently launched, with a 5m resolution, to be followed by the rover mission Chandrayaan II in 2009.
The conspiracy theorists will simple state that the photo evidence is doctored/faked. Short of taking every single conspiracy theorist to the moon there's no solution to the conspiracy (and even then they'd find a way..."it's possible now, but it wasn't then - the materials here were planted in preparation for the trip" etc. etc.). It's a no win situation, they'll carry on being deluded for the rest of their days regardless of any new evidence (there is already ample evidence to show the landings did occur as far as I and many millions of others are concerned). ny156uk (talk) 17:17, 28 October 2008 (UTC)[reply]
Short of taking every single conspiracy theorist to the moon...I like this idea. Can we leave them there? — Scientizzle 18:40, 31 October 2008 (UTC)[reply]
As noted, the believers in most conspiracy theories, including the Apollo Hoax conspiracy, believe in the existence of the conspiracy as an a priori fact. They opperate on the assumption that the conspiracy is true, and then all evidence is interpreted based on the belief that it must fit the conspiracy, and not the other way around. Any "proof" of the missions will be discarded or adapted to further prove the conspiracy, not disprove it. A wise man once said "You cannot reason a man out of a conclusion he did not arrive at by reason himself"... --Jayron32.talk.contribs 17:22, 28 October 2008 (UTC)[reply]
OK, are there any planned missions to put a satellite around the moon with the resolution great enough to see the Apollo landers NOT BY NASA? Presumably, Russia, China and India would have an interest in exposing the hoax. 12.10.248.51 (talk) 17:57, 28 October 2008 (UTC)[reply]
See the previous response. --Anon, 18:10 UTC, October 28, 2008.
But there is no hoax to expose. The people in charge of the Russian, Chinese and Indian space programs aren't stupid, so they know that. --Tango (talk) 18:20, 28 October 2008 (UTC)[reply]
They are all leftist commie countries. Of course they support the Big Government lies! Who do you think got Kennedy to fund the so-called "space program", and where did that money go? And why is China doing so well now? Makes you wonder... --Demosthenes 18:25, 28 October 2008 (UTC)
It's pretty irrelevent whether they would or would not like to see the hoax debunked - nobody is going to spend all that money just to prove that a few lunatics are...well...lunatics. But no matter what you do - the conspiracy theorists will twist it to their needs. If Russia photographed the landing site - then this would just mean that the Russians have something to hide also! There are actually three distinct groups of conspiracy nuts surrounding the Apollo missions.
  • Those who believe that neither we nor any robotic missions have ever gotten out of Earth orbit.
  • Those who believe that robotic landers have sucessfully reached the moon and/or mars - possibly including a robotic "lunar lander" and "moon buggy" identical in design to the Apollo missions - and that would be what this upcoming mission will be photographing (in their view).
  • Those who believe that only the first couple of moon missions were faked and that the later ones were real.
So even a 100% convincing demonstration that there really are a bunch of lunar landers on the moon could only impress the first group...but they won't be convinced that these photos haven't been faked anyway. Since over 20% of Americans believe it was all a hoax (at least that's less than the 65% who believe the "face" on Mars is 'real' and was constructed by aliens) - there is quite enough room for a large range of sub-conspiracies. SteveBaker (talk) 18:44, 28 October 2008 (UTC)[reply]
BTW, the face on Mars isn't quite as looney as the Apollo hoax conspiracy theory. After all, if I were a civilization living on a dying planet, a giant rock sculpture that can be seen from space might be the way I might try to preserve some record of our civilization and to say to the universe, "We existed.". 12.10.248.51 (talk) 20:02, 28 October 2008 (UTC)[reply]
I once met someone who (it seemed, genuinely) believed that the *moon itself* is a hoax. He claimed that the moonlike object we see in the night sky is at most 'a couple of hundred miles away' and was built by the Nazis in the 1940s as some sort of orbital surveillance platform (later taken over jointly by US and Soviet secret services). Any prior historical references to a moon could easily be attributed to intentional falsification of documentation and the doctoring of photographs.
Yes, that's the best/funniest conspiracy theory I've ever heard. By quite a wide margin. --Kurt Shaped Box (talk) 23:08, 28 October 2008 (UTC)[reply]
Omphalos (theology) describes the reasoning that if the Garden of Eden contained fossils and trees with tree rings inside on the day it was created, implying a nonexistent long previous period of existence, then the world could have been created last Thursday complete with eroded mountains and 6 billion people with artificial memories of the preceding Wednesday. Put THAT in your tinfoil hat and smoke it. Edison (talk) 23:27, 28 October 2008 (UTC)[reply]
Fossils? They're the work of Marxist agitators, you know. Pesky blighters are trying to discredit and bring down Judeo-Christianity as a prelude to the revolution. A teacher at my school told us. So it must be true. --Kurt Shaped Box (talk) 23:43, 28 October 2008 (UTC)[reply]
Kurt Shaped Box, if the person genuinely believed that the moon is a hoax, that's not a conspiracy theory: that's a delusion. Axl ¤ [Talk] 10:11, 29 October 2008 (UTC)[reply]
I want to invent my own conspiracy theory that the Columbus New World landings were faked and we're all still living in Europe. :) 12.10.248.51 (talk) 12:51, 29 October 2008 (UTC)[reply]
Actually, I do live in Europe! It all comes together now! --Stephan Schulz (talk) 13:19, 29 October 2008 (UTC)[reply]
There is no 'New World'. --Kurt Shaped Box (talk) 13:58, 29 October 2008 (UTC)[reply]
Actually there is considering humans originated in Africa and populated Europe and Asia before the Americas. 12.10.248.51 (talk) 15:16, 29 October 2008 (UTC)[reply]
But when did they populate Polynesia? Nil Einne (talk) 13:24, 30 October 2008 (UTC)[reply]
There'd damn well better be a new world, otherwise my recently coined adjective "novomundane" would have no use. -- JackofOz (talk) 02:18, 30 October 2008 (UTC)[reply]
I want to be an Internet denier. APL (talk) 13:04, 29 October 2008 (UTC)[reply]
What's to deny? There is no inte88.211.96.3 (talk) 15:27, 29 October 2008 (UTC)[reply]
Sigh, time was when such a comment would end with NO CARRIER —Tamfang (talk) 00:52, 30 October 2008 (UTC)[reply]
Hey! Tamfang! I wanted to find out what such a comment should have ended with - but it looks like your modem lost carrier before you could tell us what it was. SteveBaker (talk) 03:13, 30 October 2008 (UTC) [reply]
I hate when that happens. —Tamfang (talk) 07:17, 1 November 2008 (UTC)[reply]
For the most elaborately constructed bogus theory I know of - the Flat Earth Society is hard to beat. They were a serious group of people back in the 1940's - but when spacecraft started getting launched and contrary evidence became harder to deny - they kinda fizzled out and the society became a joke thing that people would join just for the silliness of it. However, they've recently had a major revival - their theories are extremely complex and really quite impressively clever. It takes some serious thinking to find ways to disprove their ravings. You're probably immediately going to think of a dozen ways to prove them wrong - but if you think you have a 'killer argument' - check their FAQ first - I can almost guarantee they've thought of an answer. SteveBaker (talk) 18:14, 29 October 2008 (UTC)[reply]
I recently got in the mail a pamphlet educating me on the great lie of heliocentricism that scientists have been perpetuating for all these years. APL (talk) 19:48, 29 October 2008 (UTC)[reply]
I was accosted in the town centre last year by a man who insisted on telling me, in a passionate and animated matter, about how Triclavianism was 'The Truth' which certain parties were trying to suppress for their own nefarious ends. He had pamphlets too. I took one, but binned it soon after. It leaves me shaking my head that people actually find this kind of thing important enough to worry and/or get upset about. Nothing wrong with taking a scholarly interest, if that's what you're into - but why the need to get all wild-eyed about it with strangers? Yes, I suspect that the answer is something along the lines of "Because they're cranks". --Kurt Shaped Box (talk) 22:26, 29 October 2008 (UTC)[reply]
By the way you can already prove we have landed on the moon at least ones with the Lunar Laser Ranging Experiment. I also just noticed how fitting the word "luna tic" is for a moon landing conspiracy theorist.88.211.96.3 (talk) 15:37, 29 October 2008 (UTC)[reply]
Mythbusters performed this experiment. But they used a NASA telescope so they clearly faked it. :) 12.10.248.51 (talk) 16:10, 29 October 2008 (UTC)[reply]
There are a couple of things that the conspiracists use to discredit that experiment:
  • There are naturally reflective rocks on the moon - some of which are natural retro-reflectors. When NASA planned the fakery - they scanned the moon with lasers to find naturally reflective spots and chose those as the "landing sites" precisely so this experiment would work.
  • Many conspiracists do not deny the existance of robotic space missions - it would be fairly easy to land a craft on the moon with retroreflectors on it - hence these are no proof that humans have ever been there.
  • Some simply claim that all of the places that have bright enough lasers and powerful enough telescopes to do the experiment are operated by people who are in league with NASA - which means that they can fake it EASILY. The fact that they are willing to repeat the experiment for people like Mythbusters is further seen as proof that they are on a mission to squash the "truth tellers".
You can't win. People who refuse to consider Occam's Razor cannot be reasoned with. SteveBaker (talk) 18:14, 29 October 2008 (UTC)[reply]

Ocean surface wave

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  • Looking at oceanic waves from a coast, what factors can affect whether they are destructive or constructive oceanic surface waves?
  • How can the nature of the wave be calculated mathematically?

Thanks in advance. Clover345 (talk) 20:04, 28 October 2008 (UTC)[reply]

Waves changing a beach are both constructive and destructive at the same time, as sand is moved from one place and put in another place. The size of the waves determines where the destruction happens. When they are big or high (eg storm surge) they get to places that humans did not plan for and demolish their constructs, and are called destructive. Big waves carry much more energy too. Graeme Bartlett (talk) 20:47, 28 October 2008 (UTC)[reply]
A good place to look at Wikipedia for some of these answers is our article on Coastal erosion. For more details, the work of Orrin H. Pilkey is considered some of the best in the field. He has done some of the most extensive studies of beach erosion, especially with regards to barrier island migration. If Pilkey's work is too advanced, or not directly applicable to your question, another good place to look is in the textbook that your teacher gave you, or in your class notes that you wrote down on the day that your teacher talked about this subject. Cheers! --Jayron32.talk.contribs 21:26, 28 October 2008 (UTC)[reply]
In detail, for water that's deeper than about 2 wave-lengths, the individual water molecules are moving around in big vertical circles. As the water gets shallower, there is no room left for the water to circulate like that - so the circular motion gets squashed into an ellipse. This affects the speed of the waves - slowing them down - so refraction of the water occurs...and this is why waves almost always come ashore parallel to the beach - no matter the angle of the beach to the deep-water waves. The slowing down also causes the waves to pile up - which results in the formation of rollers and breakers where the top of the wave is still trying to move at the same speed - while the deeper part is being slowed down by its interaction with the beach underneath. Hence the top of the wave gets ahead of the bottom - and the nice smooth sinusoidal wave gets pushed forwards so that its front is steeper than it's back. In the limit - this structure breaks apart - and that's where the surf comes from. When waves from different directions interfere - the consequences are just the classical 'sum of sine waves' interference patterns - but in three dimensions. The wind also has an effect - skewing the waves around.
You can produce rough simulations of this stuff in a computer very easily (I've done it - and the software is OpenSourced as one of the demos in the PLIB package). But these are only simulations of a generic kind. To calculate the precise shape of a real wave would be difficult because there are an enormous number of variables and much of the detail of the motion would be a consequence of turbulance and other chaotic effects that are literally impossible to calculate precisely.
SteveBaker (talk) 17:37, 29 October 2008 (UTC)[reply]

Geology, volcanology!

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obsidian, Pumice, Ryolite, Ash. What do these four things have in common? They all come from a volcano! Why they develop differently though, that's what I want to know. Why does cooling magma form 4 different types of stone. Especially obsidian. Forai (talk) 22:43, 28 October 2008 (UTC)[reply]

It's a mix of chemical composition (obsidian has a composition that inhibits crystal formation) and cooling speed (pumice cools so fast that gas bubbles are trapped within the structure of the rock). Other articles you might be interested in are igneous rock, rhyolite, and volcanic ash. --Carnildo (talk) 23:56, 28 October 2008 (UTC)[reply]