Wikipedia:Reference desk archive/Science/2006 July 10

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[edit] Leaders in thinking

I'm building the List of thinking-related topics, and I'm working on the "Leaders in thinking" section. I'm trying to find major scholars, researchers, and experts on thinking to add to the list. The emphasis is on thinking skills. So far I've found the following:

[edit] The list

Who else belongs on this list?

I'd appreciate any additions to this list. Thanks.

--Transhumanist 00:46, 10 July 2006 (UTC)

Alan Turing? Or is this just living people? —Keenan Pepper 01:00, 10 July 2006 (UTC)
Ayn Rand and Objectivism? Or am I not really seeing what you're getting at? Dismas|(talk) 01:40, 10 July 2006 (UTC)

Isn't "Experts on thinking" a little ambiguous? Perhaps you need to define the type of people that you want a little more tightly, eg. "Experts in human intelligence" or "Experts in cognitive psychology" etc. BenC7 04:03, 10 July 2006 (UTC)

I'd be tempted to add Richard Feynman, though this does seem to be a living-only list (otherwise there are a LOT of big names missing). Grutness...wha? 07:04, 10 July 2006 (UTC)


This seems a very neat idea for an article, although I'm not sure how you'd objectively qualify who belongs and who doesnt other than opinion. Maybe "List of leaders in thinking" and categorize it by field, since for each field one can probably identify respected "leaders". Look up the article or categories on genius which links to some well known thinkers, or look up category:philosophers? What'd heklp is if you define better what you are considering. FT2 (Talk | email) 13:13, 10 July 2006 (UTC)

You must include Freebytes in this list even if you are trying to be brief. I know for a fact he is a thinker, and this is not merely first hand research. There is information online indicating he is an expert thinker as well. Freebytes 18:12, 11 July 2006 (UTC)

[edit] History of Sciences

We might use some of Isaac Asimov's factual text books to help with the ideas, but I think something useful might be like a flow chart of who was first to come up with some idea in science, that is generally accepted today, like Neuton for physics. Then other science thinkers took what had been figured out by prior great minds, to come up with new theories, like Einstein. The great thinkers are the people who were first to figure out the details and communicate them effectively to the rest of the scientific world. User:AlMac|(talk) 02:18, 14 July 2006 (UTC)

[edit] Dodgy dreams...

Hi,

Sometimes when I am sleeping, I would be startled by the thought that I am tripping up in the stairs and my legs will involuntarily kick in respond to the thought. Then I would wake up.

Strangely this "dream" generates no image, i.e. I can not actually see stairs as I am having the thought of tripping up.

Can anyone explain why this happens and how can I stop having it?

--inky 03:50, 10 July 2006 (UTC)

I think this is called clonus, though the description in the WP article seems a bit different. My experience is not quite the same as yours; I usually have a dream that I remember at least a little bit of, and there's the sensation of falling and then of impact (I feel the impact in my whole body, not just my legs). As to how to stop it I have no idea; maybe just knowing that it's a common experience, and harmless (as far as I know), might put you at ease about it. --Trovatore 04:29, 10 July 2006 (UTC)
There seems to be a more specific article at hypnic jerk. --Trovatore 04:35, 10 July 2006 (UTC)
Who you calling a jerk? ;) Rockpocket 04:48, 10 July 2006 (UTC)
Thanks for that Trovatore! --inky 06:44, 10 July 2006 (UTC)

[edit] Difference between solstice and the coldest/warmest average daily temperatures

Why is there a lag time between the winter/summer solstice and the coldest/warmest average daily temperatures? For example, the winter solstice is on June 21 for the southern hemisphere, but the coldest part of the year in my city (Melbourne, Australia) is in July. Similarly, the summer solstice is in December, but the warmest part of the year is in Jan/Feb. See here for average Melbourne temperatures. -- User:E! 04:31, 10 July 2006 (UTC)

I think it's a matter of the thermal mass of the earth and water of the locality absorbing (or giving up) the heat over weeks which causes the time lag. Although the most heat may arrive from the sun at the summer solstice, it is the combination of that and the heat that is already stored in the locality which will determine the temperature experienced. (Of course there's atmospheric and oceanic mixing and many other factors involved.) I see a parallel with the general experience that a day's high temperature is typically closer to 3pm than to noon. -R. S. Shaw 04:56, 10 July 2006 (UTC)
The date of maximum/minimum sunlight corresponds to the highest/lowest average equilibrium temperature. However, it takes time to reach this equilibrium, as has been said in Shaw's post. See the seasonal lag page - User: Nightvid
Thanks to you both. The seasonal lag page is exactly what I was after. -- E! 21:00, 11 July 2006 (AEST)

[edit] Gosh Numbers

Wikiscientists, if you are interested, please help determine this afd discussion about Gosh Numbers. Thanks! Bwithh 04:38, 10 July 2006 (UTC)

[edit] Theoretical basis of miniaturization

Miniaturizing or enlarging object (or people) is a common theme in science fiction. Is anyone aware any theoretical framework which could accomplish this (not the actual machinery, but the physical processes involved)? The individual atoms and molecules would probably all have to be miniaturized, but I am not sure how this could be accomplished. I searched Wikipedia a bit and found Resizing (fiction), which doesn't really help. My quantum mechanics is quite rusty; I am not sure if electrons or quarks have radii in any sense that would need to be reduced. One problem one might run into would be violations of Heisnberg's uncertainty principle, though perhaps it would not apply or would be modified under different physics. In Isaac Asimov's Fantastic Voyage II, I believe the explanation behind the miniaturization was that Planck's constant was reduced as well, which would solve that problem. I really can't recall the format of electron wavefunctions, but I don't believe that reducing Planck's constant would size of the wavefunction (that is, the distance from the nucleus). Is there a term that one could vary to change the wavefunction in this matter? How about the electron mass? Presumably the quark and electron masses would all have to be decreased as well, otherwise you'd end up with a very dense object. Actually, maybe that would allow escape from the uncertainly principle. I lack any quantum-mechanical knowledge of the structure of nuclei, so I have no idea what would be involved in shrinking inter-quark distances to decrease the size of the protons and neutrons or what would be involved in decreasing the nucleus itself. Presumably, too, charge would be decreased too, right? Actually maybe that could provide the suitable modification to the electron wavefunctions? If anyone has any thoughts, please share. If this doesn't make sense, just ask me, and I'll be glad to clarify. — Knowledge Seeker দ 07:45, 10 July 2006 (UTC)

  • There really is no theoretical basis for this; it makes no more sense than the idea that, exposed to radiation, an entire organism would mutate, or that if you're bitten by a radioactive spider you get mysterious spider powers. It just makes for good storytelling. Notinasnaid 07:49, 10 July 2006 (UTC)
    • Ah, you're correct, but you might be misunderstanding my point. While of course one would not expect that a bite from a radioactive spider could rewrite genes in a concerted fashion throughout an organism, it is certainly plausible that someone with an altered genome, perhaps as part of in vitro fertilization, could have abilities normal humans don't have. I'm not interested in the mechanics behind any of the stories involving miniaturization, but rather if it is possible from a theoretical standpoint. Or are you saying that you don't think it's possible under any circumstances? — Knowledge Seeker দ 08:12, 10 July 2006 (UTC)
In a Farscape episode, someone who had been miniaturised observed that this was impossible. Either everything was reduced down to the molecular scale, meaning she shouldn't be able to breathe normal air (the molecules wouldn't be able to interact) or the molecules remained the same size, in which there would be just a fraction of them, which would have meant that she had just a tiny brain, insufficient to think this through the way she did. DirkvdM 09:14, 10 July 2006 (UTC)
It may have been impossible in the episode, though I'm not talking about a specific science fiction work's portrayal of miniaturization. Interactions with the rest of the universe are problematic, and probably would depend on the putative physics involved. But the air problem isn't a barrier to miniaturizing a bookshelf, for instance, or a human in a space suit. right? In Fantastic Voyage II it was a submarine-type vehicle with an onboard life-support system. — Knowledge Seeker দ 09:25, 10 July 2006 (UTC)
The problem with miniturization is that although people and objects look "big" on a macro scale, they are in fact comprized of billions of molecular level processes, and molecular physics is based upon universal forces and laws which are dependent upon scale. Thus, to shrink a person to 1/10 of their size, you have to remove 90% of their "contents". Since it's not obvious how individual processes like protein folding and synapse gaps could be "shrunk", and the balance between forces such as electromagnetic force, weak force and strong force and quantum interactions, vary according to scale, it's not clear if these molecules could be shrunk by any process. So you'd have to remove 90% of them instead. Remove 90% of the molecules in the brain? Would people's cognition not vary? So... see the problem? FT2 (Talk | email) 13:21, 10 July 2006 (UTC)
Of course I see the problem; it looks to me like you're just re-expressing my question.I am trying to explore ways in which the electromagnetic force and such could be modified. Of course it's not clear if molecules could be shrunk, but I'm wondering if anyone can think of a consistent quantum-mechanical framework for this; that's the whole point. Why are you suggesting removing molecules? That has nothing to do with miniaturization. If I chop a block of wood in half, I haven't shrunk the wood, just cut out part of it. — Knowledge Seeker দ 16:17, 10 July 2006 (UTC)
He not only re-expressed your question but also part of my answer (you cheat, you! :) ), the point of which was that if you don't do this by miniaturising the molecules (and quarks and what have you), you're left with less space, so fewer molecules for the brain. But you do mean to miniaturise the molecules. You solved the lung-interaction by limiting it to objects or putting any person in some container. But then there would still be a contact layer somewhere (unless you miniaturise the entire universe) and that should have some strange effects. Can't think of which, though. DirkvdM 19:03, 10 July 2006 (UTC)
The size of an object is not based on the size of it's particles, but rather the strength of the forces they exert on eachother. You could just place a coefficient next to every distance or displacement variable in every physics equations. If you made that coefficient 2, then the person would shrink to half their height. There is plenty of room between the atomic particles for them to get closer together if the repulsive electromagnetic forces got weaker and the attractive ones stronger. I don't know anything about the strong and weak nuclear forces, but it's simple algebra that any equation can be scaled in this manner. Crazywolf 21:44, 10 July 2006 (UTC)
Obligatory Futurama quote: "Oh my no, that would require extremely tiny atoms. Have priced those lately? I'm not made of money, leave me alone!" —Keenan Pepper 22:42, 10 July 2006 (UTC)
Thanks for all the answers, and I hope I didn't come across snippy earlier. Yeah, DirkvdM and others, I think that science fiction traditionally ignores the problematic interaction between miniaturized and normal-sized matter, though without a theoretical framework, it's difficult to predict how such interactions might occur. Of course, the way the miniaturized people were able to breath air in Honey, I Shrunk the Kids (or the dog eat an enlarged snack) is quite implausible. In Fantastic Voyage II', I believe there was a miniaturization field around the ship; it was transparent to light certainly, and not impermeable--occasionally an RBC would contact it too forcefull and become miniaturized. I wonder, too, how gravity would affect such matter. Or energy, too. Would the gaps in electron energy levels be less? Perhaps visible light would appear blue-shifted to miniaturized people. In any case, this speculation is getting too extreme even for me, so I'll stop. Thanks again. — Knowledge Seeker দ 06:55, 11 July 2006 (UTC)

There is one other means for shrinking.. though its highly theoretical and unsure if it "counts"...

Space-time itself is flexible. A procedure that flexed space-time itself, might solve the problem. Theres some big speculation on this in cosmology and the Big Bang. basically, the question is, is the universe expanding, or is space-time expanding. The former would be matter and energy moving into places it wasnt, the latter would be the fabric of space-time changing to create the illusion of space and time, in a limited bubble. Don't know if that helps. FT2 (Talk | email) 13:15, 11 July 2006 (UTC)

[edit] ionic equation

Homework question-again im interested in HOW to do it.

HCl+ KOH -------> H2O+KCl

Now i am supposed to write an ionic equation for this. The problem is that KCl is soluble in water, and water is obviously a liquid. Im at a bit of a loss as to how to write an ionic equation without having any precipates.

  • Believe it or not, without precipitates, you actually get more ionic substances. If it's soluble in water, it falls apart into ions. Take a look at ionic equation and see which form you need to use. - 131.211.210.10 08:17, 10 July 2006 (UTC)

So i take that the (unbalanced) ionic equation would be H+ + Cl- + K+ + Cl- -------> 2H+ O- + K+ + Cl- ?

What happened to the hydroxyl ion on the reactant side? You've got double chloride ions. And you should write water on the right as a molecule - H2O. It's a neutralization reaction. Even if you did want to write water as three dissociated ions, the oxygen would have a charge of -2, not -1. But it's best to write it as H2O. The K+ + Cl- on the right side is correct, though. --Bmk 13:21, 10 July 2006 (UTC)

Do the instructions say to write a full ionic equation or a net ionic equation? A net ionic equation does not include spectator ions. —Keenan Pepper 22:44, 10 July 2006 (UTC)

Split up the left hand side into its component parts. You end up with two ionic equations: K+ + Cl- --> KCl and H+ + OH- --> H2O. It is not useful to write them all completely dissociated as you have done above, as it doesn't actually tell the reader what happened. BenC7 01:07, 11 July 2006 (UTC)

Full: H+ (aq) + Cl- (aq) + K+ (aq) + OH- (aq) -> H2O (l) + K+ (aq) + Cl- (aq)
Net: H+ (aq) + OH- (aq) -> H2O (l)
-- Миборовский 22:46, 12 July 2006 (UTC)

[edit] Is there an infinite nature to the universe?

As we all know scientists have dated the "universe" to approximately 13.7 billion years old. But is it possible that nothingness is a phase of universal creation, and state that it has existed infinitely rather then arbitrary 13.7 billion years? If not, is there a acceptable name by which the inexistance of the universe should be called?--John Brown 09:54, 10 July 2006 (UTC)

soooo...what was BEFORE the creation of the universe? how were the gases and rocks (creation of bigbang?) there in the first place? what about before the gases and rocks. if there was absolutely nothing at one time in the universe, how did it get created at all? sorry about not answering the question :) -PitchBlack

There are currently no falsifiable hypotheses about what existed before the "big bang". So if you want to pick a name for whatever, if anything, came before, it's up to you :). --Bmk 13:24, 10 July 2006 (UTC)
I like to call it "Bernard". --Dweller 15:09, 10 July 2006 (UTC)
The common counter is that, with the Big Bang, time was also created. Thus, the question "What happened before the Big Bang?" is meaningless, as there was no before. --GTubio 00:04, 11 July 2006 (UTC)
I think that more proper than saying "time was created" at the big bang, it would be to say that the directionality of time (it passes, rather than just extending like 'normal' dimensions) is a direct consequence of the traumatic past event it points away from. This would mean that time would lose its timelike quality again at some point in the "future". The more you think about it, the more it appears that the universe is a vacuum fluctuation; meaning we just borrowed some energy to imagine we exist before we have to hand it back :) dab (ᛏ) 01:01, 11 July 2006 (UTC)

It depends on how you ask the question. As a personal persepective, I will die, and therefore my experience of the universe will be finite. In terms of how the universe actually is, the universe is also finite as it has a current limit of expansion. Do you mean 'Is space infinite'? --russ 23:27, 11 July 2006 (UTC)

The Bible says clearly that God designed and created everything. It's an interesting theory. --à 18:28, 13 July 2006 (UTC)

[edit] So, how clever are magpies in comparison to gulls?

While I'm sure that both species are near the top of the tree when it comes to avian intelligence, which one is the most intelligent? Has there ever been any studies on this sort of thing? Magpies certainly look smarter on the surface to me. Their look and mannerisms seem to suggest quick-wittedness and curiosity, though I know this might not nescessarily be the case. Likewise, a gull's 'thuggish' look and mannerisms make it look less smart than it probably is. I mean, they have humans pretty much sussed out, don't they? Anyone have more info? The thread above has got me thinking. --84.66.226.181 11:20, 10 July 2006 (UTC)

Magpies are members of the crow family, which are widely acknowledged to be exceptionally intelligent. See this link, for example. When there is food on my lawn, magpies have the sense to come down and eat it while the gulls merely circle noisily overhead.--Shantavira 17:29, 10 July 2006 (UTC)
I've noticed that gulls are very wary of large piles of food dropped by humans. They tend to fly around or perch nearby for a while to see what happens - they like to wait for one bird to take the plunge and go first. If nothing bad happens to him/her, the rest of the gulls pile in to feed. A sign of intelligence (c'mon - would you trust a human to give you something for nothing?) or an example of herd-mentality stupidity? You decide. :) --Kurt Shaped Box 19:31, 10 July 2006 (UTC)
WRT the intelligence of gulls, I was once told an anecdote by a friend who works at the local landfill site. Apparently, every six months or so, the local council decides to 'do something about the gulls' at the tip, so the men with guns are dispatched to 'thin the herd'. According to him, the gulls understand the concept of 'gun' very well indeed and will flee as soon as the hunters appear. What was really interesting about this story was that the gulls apparently know the difference between rifles and shotguns (presumably after seeing several of their fellows being shot down over the years). If they see a shotgun, they take off en-masse into the air and fly as high as possible, out of the range of the pellets. If the men have rifles, the gulls panic and get out of the area as quickly as possible, keeping low to the ground, flying at high speed and zig-zagging, as though they know how to throw off their aim. I've never seen this at first hand but it's certainly an interesting observation, if accurate... --Kurt Shaped Box 20:01, 10 July 2006 (UTC)

We seriously need to start a separate "Gull" reference desk :) --Bmk 21:25, 10 July 2006 (UTC)

I was watching a baseball game the other day which started at 2 PM local time, although the games usually start at 1 PM. When the games are over, the gulls swoop down to pick through all of the garbage left behind. They showed up an hour before the end of the game, apparently totally confused by the late start time. Apparently, they carry wristwatches.  :) User:Zoe|(talk) 02:35, 11 July 2006 (UTC)

[edit] Whats my groggy feeling after stretching?

sometimes, when i get a really good stretch (standing up, arms high up) i get a really groggy and tired feeling over my body for maybe 15 seconds. i dont really know why this happens. probably the best guess i can come up with, is that while stretching all those muscles, chemicals are released to relax you? or probably relax the muscle? somebody please clear this up for me. -PitchBlack

This is my guess, but I always assumed it is because it takes a while for the heart to start pumping fast enough to accomadate the active state you have just entered suddenly, and time for the pressure to psread arround the body. Philc TECI 17:09, 10 July 2006 (UTC)
It's called orthostatic hypotension. Baseball,Baby! balls•strikes 03:05, 11 July 2006 (UTC)

[edit] Disabled Task Manager

Someone (or more likely, something) has disabled the task manager in my Windows system. How can I restore it? Thanks. —The preceding unsigned comment was added by 85.50.38.173 (talk • contribs) 14:27, July 10, 2006 (UTC).

Your box has been rooted. Run a spyware and a virus scan. If that does not work, reformat and install Ubuntu. —The preceding unsigned comment was added by 207.75.179.101 (talk • contribs) 14:43, July 10, 2006 (UTC).
Could you be a little more precise? What happens when you right-click on the taskbar and select "Task Manager"? On a shared/office machine, the administrator can disable task manager for users of this machine - could that be the case? If you are using a standalone machine, as the above user said, first check for spyware/viruses, some of them disable task manager to make it harder to get rid of them. If that's not the problem, try the procedure on this page: [1] (for Windows XP). Googling your problem also yields some results: [2]. Good luck! — QuantumEleven 13:21, 10 July 2006 (UTC)
A lot of networked computers have the task manager disabled to disallow tampering. --Proficient 16:40, 10 July 2006 (UTC)

[edit] can the fruit conduct electricity?

If it is so, why is that so?

Fruit conducts electricity because it is basically a fleshy bag of electrolyte solution; that is, water with salts dissolved in it (and a bunch of other stuff). It conducts because the charged ions are free to move and carry current. If you connect fruit to an electrical circuit, instead of free electrons, free ions take over in the fruit as the moving charges. See electrolyte for more info. Also, I think in some cases the non-liquid parts of fruit are responsible for conduction; I imagine orange peel for example is not a great insulator - it probably has significant conductivity. --Bmk 13:28, 10 July 2006 (UTC)

You can make a single-cell Voltaic pile from an orange, by just attaching copper and zinc electrodes. The voltage will be enough to light a small lightbulb if you wire it up. Also works with sweet potato. Works best with cooked and unpeeled sweet potato. --Kjoonlee 17:49, 10 July 2006 (UTC)
NOT TRUE! Fruit batteries are far too weak to power even the most sensitive incandescent bulb. (Yet people who have never tried the experiment keep claiming that it works. It's a kind of gradeschool science Urban Legend.) To test a single fruit battery, listen to the clicks when you touch the wires from headphones to the battery's metal plates. On the other hand, three or four fruit-batteries in series can light up a light-emitting diode. LEDs require far less current than flashlight bulbs, but LEDs need about 1.6v before they turn on, while fruit batteries create less than one volt.--Wjbeaty 16:58, 11 July 2006 (UTC)
Just a note - the "orange battery" is a result of another phenomenon - redox reactions. --Bmk 18:27, 10 July 2006 (UTC)
Acidic fruits such as oranges are much better conductors than non-acidic ones such as melons. --Ginkgo100 talk · contribs 22:42, 10 July 2006 (UTC)
The reason cooked sweet potato is better than raw sweet potato is because the cell walls get ruptured after cooking, leading to more electrolyte and more current. I wonder if anyone's tried with cooked orange. --Kjoonlee 06:12, 11 July 2006 (UTC)
Barbara Zalat and Jonathan Frutt did a thesis on this. They found that the best demonstration of this so-called Frutt-Zalat effect is obtained by mixing up some apples, bananas, oranges and melon, sprinkling with 0.1 molar cinnamon and clove mix, and attaching a car battery to it. Stand well back and ensure someone else takes the blame, as if you do this without due skill and preparation it will cause a minature black hole to be created as a byproduct :) FT2 (Talk | email) 14:41, 11 July 2006 (UTC)

[edit] Deflating tyres

At a gas/petrol station, there is a machine to inflate/deflate car tyres, and ensure they are at the correct pressure. While using such a machine the other day, I noticed among the many instructions one which I couldn't immediately explain: "do not deflate hot tyres". This had me somewhat puzzled - why not? — QuantumEleven 13:15, 10 July 2006 (UTC)

See the combined gas law for a quantitative explanation. Basically, when tyres get hot, the pressure inside the tyre increases despite there being the same mass of air in there. The pressure on the placard is intended to indicate the correct pressure when the tyres are cold. --Robert Merkel 13:41, 10 July 2006 (UTC)
Right - so if you deflate tires while they are hot, then when they cool down - if it rains or something, then they will deflate further to below a safe pressure, and you could lose control of the car. --198.125.178.207 14:10, 10 July 2006 (UTC)
Ah, I see. Thanks very much everyone! — QuantumEleven 07:45, 12 July 2006 (UTC)

[edit] Rename files using VB .NET 2003

I need to write a program in VB .NET 2003 to search through a folder (and all its subfolders) and rename all the files ending in .mov to .txt. How do I go about doing that? Thanks, 86.41.166.192 15:21, 10 July 2006 (UTC)

First maybe take a look at some of the file system functions here [3] that you can use to play with and select paths. You can find some sample code to get lists of subdirectories or files here [4]. Then you'll want to use the rename function [5]. That should be a good start. 128.197.81.223 17:14, 10 July 2006 (UTC)

[edit] Observable Ray of Light

I often find that while observing an isolated source of light I can see what appear to be rays or concentrated beams which are not directly incident on the eye. i.e I appear to see straight lines of light emerging from the source in divergent directions but only ones which point in directions at an angle from my frame of reference . Could someone explain this phenomenon.

Lens flare basically? 128.197.81.223 17:16, 10 July 2006 (UTC)

I think what you are seeing are indeed rays of light, or rather the photons in the rays that are scattered. Basically, when a light source emits light in all directions, the emitted photons propagate along radial rays. However, when the source emits into a molecular medium like air, some photons are scattered. Therefore, if there is some isolated ray, such as one from the sun through a hole in the clouds or from a flashlight, you are seeing photons that were originally traveling along the ray, but then hit an air molecule or particle in the air and were scattered into your direction. --Bmk 18:10, 10 July 2006 (UTC)

You seem to be referring to Rayleigh scattering, which does indeed occur, but is very likely not to be what is going on here. Part of what you're seeing may come from diffraction caused by your eyelashes. While you didn't specify, I imagine this most often occurs with a bright light source in otherwise darkness. I maintain that my analogy to lens flares is probably also somewhat correct: There are multiple surfaces in your eye off which the incoming light may be reflected, which could cause the effect that you are describing (or perhaps would only cause a hazy sphere around the light, but I expect you see that too). Here [6] is a bit o' text on a related phenomenon. 128.197.81.223 21:56, 10 July 2006 (UTC)
You may be right about other optical effects - I'm not entirely sure what the effect is that the question refers too. I thought it meant the phenomenon of seeing a flashlight beam which is not directed at the observer's eye. Just to clarify what I was saying, the only way for photons from a light ray which is not directed at the observer's eye to reach the observer's eye (and therefore be seen) is for them to be scattered from the medium through which the ray is travelling. If a ray is travelling near an observer but not on an intersecting path, and it is not scattered from its medium (for instance if the medium is vacuum), the observer will not observe it at all. That is essentially why space looks black when you're in space. --Bmk 22:05, 10 July 2006 (UTC)

Thanks. The link [7] does relate to exactly what I was referring to. I have to say I preferred to think of it as Bmk suggests rather than as explained in the article. Nevertheless I would like to verify my understanding of this explanation. According to what i understood the straight lines or rays I see are produced within the eye by light passing selectively through diffracting layers of the cornea and tears or fluids just over the cornea. Is this accurate?

I wrote the eyeself.txt article (now moved to eyeself.html .) Yes, the "rays" come from the eye, but mostly they come from reflections off the eyelashes, while some vertical stripe "rays" come from the fluid meniscus at the edges of your eyelids. Hold your eyelids wide open. If the "rays" vanish, they were from eyelashes. Or do the opposite: squint your eyes almost closed, and the "rays" become larger and more numerous.--Wjbeaty 16:52, 11 July 2006 (UTC)

[edit] unknown pain

Dear sir/madam, My husband is a diabetes patient and he is not under medication. For nearly a year he is suffering from pain on the right side of his body below the chest region. We couldn't guess the cause for the pain. I doubt whether his kidney is getting affected. Kindly help me with some possible suggestions.

Thanking you. Anu

It is possible that someone on this reference desk can give you useful information, but it should be noted beforehand that any information here is not a substitute for a licensed medical professional's care; you should see a doctor if you can. I hope you find a solution that can help your husband --Bmk 21:11, 10 July 2006 (UTC)
I'm an RN, and I second the opinion that your husband should see a physician and that my comment here is not a substitute for that advice. However, upper right quadrant abdominal pain is likely a sign of either cholecystitis, which is inflammation of the gallbladder, or cholelithiasis, which is gallstones. Does the pain get worse after he eats, especially when the meal is fatty? If so, the gallbladder is probably the origin of the pain. A kidney infection would likely produce right flank pain, in his back, not in the front.
It won't get better on its own, and complications are possible if left untreated. Please take your husband to see a physician as soon as possible, because he may need surgery. Good luck. Baseball,Baby! balls•strikes 03:16, 11 July 2006 (UTC)
You probably should go to the doctor. --Proficient 23:00, 12 July 2006 (UTC)

[edit] How many time it takes for a dog carcass to decompose

How many time it takes for a dog carcass to decompose? My problem is the following: I have buried my deceased boxer in a field about one year ago, however, the field needs to be ploughed. Is there any change of disintering the dog's carcass? Mário 20:49, 10 July 2006 (UTC)

Unfortunately, there are many variables that can affect the decay time for your dog. You can look at decomposition if you'd like. It says there that decay time underground is about 8 times slower than decay time on the surface. In my opinion, your dog's skeleton will certainly still be there, but i would guess that most of the soft tissue is gone by now, especially if you live in a warm climate. If you live somewhere colder, there's a chance decomposition is still taking place. --Bmk 21:07, 10 July 2006 (UTC)
Yes, I live in Portugal, it's warm here. In 2005 a severe drought affected the country, but 2006 has been a rainy year, if that matters. Mário 21:55, 10 July 2006 (UTC)
I don't know much about it, except from seeing deer carcasses in the forest, but my guess is there isn't much left except bones. And I think rain would speed the process. Someone else might have a better/more educated guess, though. --Bmk 22:00, 10 July 2006 (UTC)
Corpses in a bog can mummify to a Bog body. It hardly decomposes there partly because there isn't enough oxygen for it. If the field has been ploughed before, not too long ago, that would have loosened the ground and let air in, which would help the decomposition. DirkvdM 06:17, 11 July 2006 (UTC)
Probably only bones are left. --Proficient 23:01, 12 July 2006 (UTC)

[edit] Quicktime DAT/IDX files

I have an old CD-ROM with a lot of Quicktime media stored in a pair of files called VAULT.DAT and VAULT.IDX. Is there any way to extract individual video files from these files? I've tried Googling around but not found much which was helpful. --Fastfission 21:42, 10 July 2006 (UTC)

It might be that the quicktime files are stored in a database which comprises .dat (the data) and .idx (database index) files. You may be able to find some software to access them, but I can't recommend one offhand. If the database is a B-Tree of the proper format, this [8] might help you. 128.197.81.223 22:03, 10 July 2006 (UTC)

[edit] water supply for trees in urban environments

The rainfall in urban areas is generally diverted to the storm-water system, and never reaches the soil. The trees in the cities are usually growing from relatively small openings in the concrete - much smaller than the footprint of the tree's root system. How do urban trees get the necessary water? Is their root system/physiology different than their "natural" counterparts'? -- Nikola 69.5.153.125 23:47, 10 July 2006 (UTC)

A quick search didn't yeild an answer to your question, but Urban Forestry lists lack of water as one of the possible challenges of urban forrestry, so your question seems a valid one. A solution probably has to be found on a location by location basis. Some possible solutions would be to pick a species of tree that can survive with little water, position the tree so that it recieves runnoff water from buildings or the storm water systems, or to simply water the trees regularly. Crazywolf 00:56, 11 July 2006 (UTC)
My understanding is that municipalities typically irrigate their trees. This is usually the responsibility of the Parks Department or a similar department. The trees' root systems, of course, extend under infrastructure like sidewalks and roadways. --Ginkgo100 talk · contribs 19:10, 11 July 2006 (UTC)

See Groundwater, Water table and so on. In britain, where I live, if you dig down deep enough you will eventually reach water, like a well. Even when you're not deep enough to reach the water table the earth is still damp, and even if its surface is covered the moisture still slowly passes through the soil so that no parts are left dry. I expect its different in a desert though.

Farmers and others sometimes use a plastic sheet as a mulch. This provides more water for the plants as it stops the soil from drying out. So what you have described could be beneficial to trees. --81.104.12.1 01:47, 16 July 2006 (UTC)