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How big must it BE?........

I hope you weren`t thinking "dirty" here, but, here`s the question... How big, in aperture, would a ground-based optical telescope have to be to able to 'just' glimpse a man-sized, let`s say, object, on the Moon. Let`s also say that the Moon is at its mean distance, assume 'perfect' optics, 'perfect' observing conditions, object is "lying down" on the Moon`s equator, etc.....I`m guessing around 300 feet of aperture. I think Dawe`s Limit might prove helpful. I don`t need to know HOW to make the calculations,,,as this is certainly NOT homework,,,,just curious. I hope you have fun with this,,,and Thank You. 152.163.100.74 00:07, 15 October 2006 (UTC)

The "how" is at angular resolution. --Robert Merkel 00:39, 15 October 2006 (UTC)

(:)Boy! Thank you so much,,,,THAT was helpful. I thought this might have been interesting for OTHER readers. Was it easier to answer the "how" rather than give the real answer? Thanks again. 152.163.100.74 00:54, 15 October 2006 (UTC)

What's with,,,,,,the commas? Vitriol 01:02, 15 October 2006 (UTC)

What about commas don`t you understand?....pause to think. 8 ). 152.163.100.74 01:08, 15 October 2006 (UTC)

Edit'd for the destruction of confusion. I mean, why do you sometimes,,,,,put strings of commas in your posts? Vitriol 01:10, 15 October 2006 (UTC)

(:::) I hope I did this correctly. I`m just a newbie here. I guess my commas are for extended pauses, as one might do qhile simply talking with someone, a nuance, I guess. I offer total and complete apologies for any confusion. I think I need to go to the help desk to better understand how to ask and reply to information. Again, so sorry. Now,,,how big must that telescope be? 8) All jokes aside. Sorry, forgot to sign, but, really, how big must that telescope be? Dave152.163.100.74 02:04, 15 October 2006 (UTC)

You are looking for an Ellipsis for that effect (...). Sorry, I don't know anything about the question. --liquidGhoul 02:53, 15 October 2006 (UTC)

For heaven's sake, the calculations are a bit of high-school trigonometry, a bit of arithmetic, and most importantly a bit of effort to dig up the right numbers to plug into the calculations. FWIW, I get a result suggesting you'd need a telescope about 2 kilometres wide, which is not implausible given the numbers quoted in Apollo Moon Landing hoax accusations. .--203.214.55.189 03:32, 15 October 2006 (UTC)

With a telescope 2 km wide, you'll be able to resolve details as small as 8.6 cm. It would be helpful, but unnecessary. --User:Bowlhover 05:15, 15 October 2006 (UTC)

That's what I was working on. I was making the assumption our human is standing upright rather than lying there sunning himself...--Robert Merkel 10:50, 15 October 2006 (UTC)

However, for completeness, you could instead use interferometry to, in effect, synthesise a telescope of that size. --203.214.55.189 03:34, 15 October 2006 (UTC)

Well, I didn`t want to use interferometry but, the distance between 2 'lenses' would turn-out to be exactly what the diameter of a single lens would be anyway. As for 2 kms...that sounds WAY too big. Are you sure about that? Did you do any calculations? Here`s a start...Dawes Limit, in arc-seconds, is d/4.5..."d" being in inches of aperture of primary. Moon is approximately 30 minutes of arc. A 6 foot object at the equator is a tiny fraction of an arc-second. Do you need a 2 km-wide primary to resolve that? Dave152.163.100.74 03:58, 15 October 2006 (UTC) Small correction, and more help....Dawes Limit d/4.6, Moon is approximately 2000 miles in diameter and subtends approximately 30 arc-minutes. Now divide 6 feet into 2000 'miles-worth' of feet, the quotient being THAT fraction of 30 arc-minutes. Plug that into the Dawes Limit equation, and the diameter of the primary should be the answer to my initial question. Now, as per my initial question, "Did you all have fun with that?" Dave152.163.100.74 04:29, 15 October 2006 (UTC)

The largest man-made object on the Moon is 5 metres large, which is Atan(5/363 104 000)==7.88*10^-7 degrees as seen from Earth. (363 104 000 is the distance, in metres, to the Moon.)

From the angular resolution article:

$\sin \theta =1.22{\frac {\lambda }{D}}$

Sin(7.88*10^-7 degrees)/1.22 = 1.1*10^-10

 Finally, "an" answer, and very close to my initial guess. Thank you very much! Dave 152.163.100.74 05:20, 15 October 2006 (UTC) 

380/(1.1*10^-10) = 3.367*10^10 nanometres = 33.7 metres --User:Bowlhover 05:06, 15 October 2006 (UTC)

A qualitative answer from half-remembered college physics: You make the lens LARGE to increase the light gathering ability and image faint distant stars. You separate the two lenses and combine them interferometrically to enhance resolution. So two or more small lenses at a distance apart could resolve the stated target at a lower cost than building a very large lens to achieve the same objective.Edison 05:50, 15 October 2006 (UTC)

Yes actually some people are considering these multiple (distant) lens telescopes. I believe it was in the New Scientist some time this year or perhaps last year Nil Einne 15:42, 15 October 2006 (UTC)

Don't forget to take in to account the earths atmosphere Nil Einne 15:40, 15 October 2006 (UTC)

Thank you very much for all your replies. Very interesting. Dave 205.188.116.74 15:55, 15 October 2006 (UTC)

Come nuclear armageddon...

...will the gulls survive? I was just watching them flying around today and musing to myself "you're smart, you're resoruceful, you're self-sufficent, you're adaptable, you've learned to live off us but have not come to rely on us, you still know how to survive, you do what you must in order to live, you just carry on with your life, unconcerned with all the bullshit that's happening below you - as long as you have a full belly, a safe place to sleep and occasional sex, you are content with your life". I started comparing the gulls to us and realized, in a slightly profound moment, that somewhere along the line, we've lost some of the things that they still have - to our detriment. So, when/if the bombs fall - what are the odds that more gulls than humans will make it through to see the daylight again? Sorry if this all sounds a bit off-the-wall, it's quite late here and I sometimes get a bit 'deep' at this time of night. --Kurt Shaped Box 01:30, 15 October 2006 (UTC)

I think the question here is, "will the Reference Desk gull questions survive?" Vitriol 01:38, 15 October 2006 (UTC)

Maybe following armageddon, a 'gull world order' will arise to fill the niche we left behind - causing the WP ref. desks (or the gull equivalent thereof) to be deluged by questions from adolescent gulls worried that their adult plumage hadn't grown in yet. I'd imagine that if gulls had evolved enough to use computers, there would be plenty of five-year-old gulls neurotic about still having some brown feathers whilst all their peers were snowy-white. Oh yeah, they'd probably freak out the first time their breeding hormones kicked in too - cock birds worried about the sudden uncontrollable feelings of sexual aggression they were feeling, hen birds worried about unexpectedly laying unfertilized eggs, etc. --Kurt Shaped Box 10:40, 15 October 2006 (UTC)

I would think birds would be particularly susceptible to fallout, since they fly through it. Meat-eaters would also suffer from an accumulation of radioactivity that gets more severe the higher up the food chain you go. So, I would expect gulls in areas of fallout to be wiped out. Gulls in unaffected parts of the world should survive, assuming there isn't a "nuclear winter". StuRat 03:14, 15 October 2006 (UTC)

The radiation would cause them to mutate thusly. (actually only gulls that live by the bay, bay gulls --WhiteDragon 18:08, 16 October 2006 (UTC)

The gulls would survive a nuclear winter. The world would be a feast of carcasses. The larger species would hunt the other scavengers. They would also eat the cockroaches. :) --Kurt Shaped Box 10:31, 15 October 2006 (UTC)

Please God, No! Ordinary cockroaches are one thing, but cockroaches with wings? --Light current 12:38, 15 October 2006 (UTC)

Don't most cockroaches have wings? Nil Einne 15:38, 15 October 2006 (UTC)

Many adult cockroaches have wings, and some – for example the Asian cockroach – can fly quite well.  --Lambiam^Talk 16:07, 15 October 2006 (UTC)

But not as high as a kite!--Light current 13:48, 16 October 2006 (UTC)

What could be a physiological explanation for the Chinese folk medical concept of 熱氣 ("heat")?

I'm not sure if the concept is in the orthodox theories of Traditional Chinese Medicine (it may well be), but I'll just call it a folk medical concept. The concept I'm referring to is 熱氣 ("rè qì" in Pinyin romanization; Literally, 熱="heat" or "hot", 氣="gas"). As best I can describe it, it is a syndrome with (some or all of) these associated symptoms:

• a general feeling of hotness (the body temperature may be normal or only slightly elevated),
• sore throat,
• a feeling of thirst (despite plenty of fluid intake),
• yellow (and possibly foamy) urine,
• lips that look a darker shade of more red than normal, and
• a sensation that the air exhaled through the nostrils is warmer than usual.

The syndrome is often attributed to over-consumption of certain kinds of food (e.g. deep fried foods (especially overcooked or burnt), spicy food), or under-consumption of the antagonistic kinds of food (described as "cooling"). According to (folk?) Chinese medicine, to stay healthy, one should consume food in antagonistic categories in balanced quantities.

Can someone think of one or a small number of body conditions, in physiological terms, that can explain the symptoms associated with 熱氣?

[Edited to add:] 熱氣 is a well-recognized phenomenon in Chinese (folk?) medicine but, as far as I can tell, is not recognized as a syndrome in western medicine. I suspect that the symptoms are not unrelated but manifestations of one (or perhaps a few) underlying conditions, which should be describable/explainable in scientific terms. I'm hoping to find a correct scientific explanation, or at least a testable theory, for the phenomenon. --71.246.5.19 04:51, 15 October 2006 (UTC)

• Yes 熱, that would be a normal state, so 熱熱 would mean there is to much (double). Mion 04:55, 15 October 2006 (UTC)
  • Tricky thing is what is your source ? as all medicine had to be converted to the local farming population, the source can quote a mainstream medical in that time or a local one in that time. ?. Mion 05:21, 15 October 2006 (UTC)

No, there isn't. At least none that i've heard of. And i don't think there will be - because the concept of heat is a large collection of symtoms that chinese medicine explains with an umbrella concept of "heat energy" in the body. I'd say many of them, if not most, are not actually so closely related. Most of the individual symptons can be explained pretty easily with simple biology. For example, one of the things i often hear is not to eat too much lychees - because lychee is apparently very hot, and eating too much lychees gives you the traditional symptons of heat, most notably...people easily get blood noses from it. This goes for most tropical fruit as well. It's like, chinses medicine would say "eating lychees --> lychees are very heating --> therefore people get symptons like blood noses". Western biology will probably just explain it as that tropical fruit probably contains compounds which in some way affect the permeability of small blood vessels, the blood vessels in the nose which contribute to blood noses are very fragile. More permeability = much easier to rupture = much higher chance of blood noses. This is pretty much the same as people with hay fever get blood noses very easily on hot dry days (hay fever = an allergy to flower pollen. very common in some parts of the world.)

anything that increases your metabolsim will most likely give you a general feeling of hotness and excitment, a feeling of warm exhaled air, and redder lips. For example, exercise increases metabolism - if you go for a run, you will feel very warn, get redder lips, and the air you exhale will feel warmer because your body temperature is heating up. Although the normal body temperature is about 37oC, your body can tolerate a few degrees higher. And when you exercise, you're body temp will normally increase a few degrees before cooling mechanisms kick in. A lot of those foods that cause heat increase metabolism one way or another, although not nearly as much as how your metabolism increases when you go for a run. Spicy foods are described as "hot" in english for good reason - because that's exactly what they do. The "spicy"-ness tastes hot, and makes you feel hot. A chinese person will just tell you it's 'heat'.

Something like the color of urine is also very easily explained. Urine varies in color a lot - lighter color urine means there is more dilute and more water. Go drink 2-3 liters of water in one shot, and take a look at the color of your urine the next time you piss. You should find it is very clear, almost colorless. Where is if you go for a day without drinking, you will find your urine very dark. You'd also find yourself very thirsty. When youre body doesn't have enough water, you feel thirsty, and your urine turns dark. Because your body will try hard to conserve water - and a very good way to conserve water is to have less water get peed out. Coincidentally (or maybe not so), being hot expands a lot of water. Because normally when youre feeling warm/hot, you also happen to be sweating. Which wastes/uses a lot of water. Warm air also tends to be more moist.

It is not very surprising that one of the 'fixes' for heat is to drink water. Which tends to fix most of those symptons, for example...the dark colored urine. A chinese doctor may tell you it's because the water helps balance your body, and fixes the fact that you've eaten too much heat food. I'd just say drinking more water = pissing out more water, and therefore you have a more dilute urine. Foods which are cooling, like pears, happen to be very light (not much digestible stuff to digest) and very juicy. Once again, the water.

Anyhow, i've never actually read anything about chinese heat from a western medicine's point of view. It would be very interesting to see what western medicine does say on it. But those are just the explainations that i would give as a bio student if someone just told me about the symptons (i.e. i ate this and this and noticed i had this and that sympton) based on general human biology.

Thanks for responding. Your suggestion of increased metabolism is a good start, whether or not it turns out to be part of the correct answer. I still think that the symptoms are explainable in terms of some underlying physiological conditions. A few additional comments:

• The feeling of hotness causes by spicy food persists for only a relatively short time. The feeling of hotness from 熱氣 persists way beyond the disappearance of the immediate effects of consuming spicy food. So, the role of spicy food in 熱氣 is beyond that of a short-term stimulant.
• Increased blood vessel permeability is one possible explanation for the increase likelihood of nose bleeding, but it may not be the only hypothesis available. Raised blood pressue, and perhaps a number of other mechanisms that I'm not aware of, may be the (more principal) cause of the symptom.
• The subjective sensation of hotness, both in the body and in exhaled air, does not necessarily correlate to increased body temperature. From experience, I know that the sensations are sometimes felt when the orally measured temperature is normal or even below the nomimal normal body temperature.
• The color of the urine may correlate to a state of (de-)hydration, but that's probably not the full story. More concentrated urine does not directly explain the foaminess (sudsiness?) of the urine. It seems to me that something in the urine is responsible for the apparent reduction in surface tension. Also, the subjective feeling of thirst is not caused by dehydration alone. It can persist even when one has drink so much water than urination becomes frequent and the urine passed becomes colorless. I should note that there's at least one allegedly very effective herbal remedy for the "thirst" symptom.

--71.246.5.19 14:55, 15 October 2006 (UTC)

medical Flower? it would explain the increased metabolism, next time i'm going to ask the farmers first about it.. Mion 10:23, 17 October 2006 (UTC) ?

I asked my friend (he's a farmer}, he said best is once daily after meal, in the beginning its not a problem if you skip a day. reg. Mion 11:17, 17 October 2006 (UTC)

Western medicine  : Λ

.................................... V

there is another possible model to explain the "heat" phenomena.one example is the eruption of acne, which often is associated with "heat", because the acne is red and is believed to relate to congestion of hot greasy spicy food. physician use diane 35 to treat acne effectively, which is an oral contraceptive pill with significant anti-androgen effect.if androgen is "heat" prone, while oestrogen is having the opposite effect, ie "cold" prone, i wonder could "heat" and "cold" can be explained by ratio or balance of body hormones which have opposing effects. if the total sum of "heat" prone hormones are more than "cold" prone hormones, then the person will manifest an "heat" phenomena externally.another example is hyperthyroidism and hypothyroidism, too much thyroxine will give the "heat" picture (patient feels hot, thirsty etc) while lacking thyroxine will give a "cold" picture, (cold limbs, low evergy state). other possible explanation is the immune system, the degree of activation of various immune cells and inflammatory chemicals.

six pack

is there a way to tell if you have a six pack without removing the fat through excercises such as running but just by doing sit ups?

Well of course you have one; everyone has a rectus abdominis muscle. However, any belly fat will obscure it, so it will not be prominent unless you have a low body fat percentage. Since sit-ups don't remove fat as well as aerobic exercises such as running, no, you will probably be unable to achieve a defined six pack without running or doing other supplemental exercise. Hyenaste ^(tell) 05:52, 15 October 2006 (UTC)

I would say that a "six pack" means having well defined abdominal muscles which are visible (not obscurred by fat). So, by definition, you don't have a six pack if you can't see it. Your question is something like "How can you tell if an 800 pound woman has a pretty figure under all that fat ?". StuRat 20:38, 15 October 2006 (UTC)

fine is there a way you can tell that you are ready to start running to show the six pack after lots of sit ups

You don't need a lot of muscle to have a six pack if you also don't have a lot of fat to obscure it, I'm a really lean guy, I never do sit ups, but i have a six pack, just because I have very low body fat. My friend is a gym instructor twice my size, he went on holidays and put on about 10 kg, bam, no six pack, even though his muscles would be twice the size of mine. Sounds to me like you are just procrastinating about losing the weight. If you want to sculpt, you can do both aerobic and weight training, it will take you twice as long to build the muscle and then lose the weight. PLUS if you go full on with weights without losing the fat you can easily end up with stretch marks when you lean down, which is not pretty. Don't forget to sign your posts. ;) Vespine 04:14, 16 October 2006 (UTC)

Seeing Colors

When I look at the color red do I see the same thing as what other people see when they look at it? Is there a way to know for sure?

You see almost the same thing (assuming you are not color blind). Seeing as everyone has a different genetic structure, it is impossible for everyone’s Cones and Rods to develop EXACTLY the same. However, seeing as every healthy person has similar Cones and Rods, what you are seeing is similar to everyone else’s. The color cannot be exactly the same, but it is VERY close. THL 07:32, 15 October 2006 (UTC)

You see with your brain not your eyes. Philc _T^E_C^I 20:09, 15 October 2006 (UTC)

Seeing is also experiencing. Even if the underlying hardware (the sensors) is the same, the interpretation by the brain, the experience, may be very different. I have thought about this a lot, and this is getting a new impulse now that I am reading up on Alzheimer. Different people can have very different perceptions of the same thing. knowing how they experience something may seem imposible, but magic mushrooms can give a hint. They can make you see colours that you never saw before, even though you are viewing the very same things you normally see. If a brain on mushrooms can see those colours, the what might another person see? No answer, but an indication of how differently minds can percieve the same things (assuming there is an objective reality out there, but let me not go into that). DirkvdM 08:47, 15 October 2006 (UTC)

If you believe you may be color blind, you can get that checked by a doctor. Dismas|^(talk) 10:35, 15 October 2006 (UTC)

(This is strictly for clarification) Dirk raises a good point. My answer doesn't contradict his, nor does his mine. Shrooms cause some major chemical imbalances in the brain (be they temporary ones); therefore, a person with a brain having differences drastic enough to cause a change in perception would (by our definition of "normal") be unhealthy. THL 10:53, 15 October 2006 (UTC)

The color you see is physically the same. What you call red is the same wavelength as what everyone else calls red (assuming neither you or they are color blind). But color, like all perception, is very subjective. Have you ever like...looked at something really bright white (like something that was actually *shiny* white), and then looked at a sheet of normal paper and suddenly realized the paper looked really yellow...and not so white at all? Or seen someone who has black hair, but looks slightly brown in the sunlight. But then when you look at it outside of the sun, you swear it is 100% black? --`/aksha 12:42, 15 October 2006 (UTC)

The latter has to do with the fact that lightbulbs do not emit all light wavelengths, where as the sun does. Under artificial light, the person's hair is black, and out in the sun the person's hair is brown. The hair can't reflect what isn't there. The former is an interesting point. I'm really not sure what to say about that. I don't know much about the brain itself, so I don't know how to address the initial perception. However, seeing as the experience carries over to everyone, that shows that the brains of healty, "normal" people are similar in many ways. THL 14:35, 15 October 2006 (UTC)

If you mean: "Do you have the same subjective experience?", well, that question is intrinsically unanswerable, and it can even be argued that it is meaningless. See further the article on the philosophical concept of "Qualia".  --Lambiam^Talk 16:20, 15 October 2006 (UTC)

You see with your brain not yours eyes, your eye recieves information, your brain sorts this into a visual image which you interpret. Therefore I would say that the chances that you see the same thing are extremely slim, but as long as you can tell the difference between colours, light shades etc. it doesnt really matter. Philc _T^E_C^I 20:09, 15 October 2006 (UTC)

There have to be some major similarities because we all view the same colors as being complementary. I also think that if people's interpretations of colors were at much variance we wouldn't have the relatively similar perceptions of art which are made up from mixes of many different colors. (There is a bit in Niven's [[[The Mote in God's Eye]] where the humans come across alien painting and find it incredibly unpleasant to look at since their perceptions of colors are so different.) I imagine if people were too off you'd get more of the "I don't see what you see" or "Why is this weird color placed here?" that you get when trying to talk about colors with someone who is colorblind. Without any compelling reason to think that humans have terribly different perceptions of color, I wouldn't assume it; color vision evolved long before humans were around, and while there are no doubt some slight variations in it, I don't see any reason to assume that amongst people there would be fantastically different views of it. I once took a class ages ago with a psychologist who had done a lifetime's worth of work in color vision who basically said the same thing — there is no indication that humans perceive colors with any great difference from one another (except colorblindness, which is a problem with the physical structure of the eye), so there's no good reason to assume there is much of a difference from person to person. --Fastfission 20:21, 15 October 2006 (UTC)

Lack of evidence for something is not evidence against something though. Especially since this is something that it is impossible to experiment with, as we will only ever see the colours wee see. You would still be able to distinguish colours and see the same relationships between them, as that is information carried in the wavelength of the colour itself, but perception and understanding of this information is something different. Philc _T^E_C^I 17:31, 16 October 2006 (UTC)

How Many calories does a Gram of Human Fat Have?

How many calories (note lower-case c) does a gram of human fat have? THL 07:22, 15 October 2006 (UTC)

One for every degree it can heat a litre of water. Sorry, that was silly. :) BINAS gives 37 kJ for cod liver oil, which is pure fat. If you want that in calories, you'll have to convert it yourself because I don't do obsolete units. I'm not sure, though, what this means. Is that the amount of energy that can be extracted by a healthy human (with an empty stomach?) for actual use in muscle power or to heat the body? I have wondered about this before. What does the amount of energy given on food packaging mean? And your question seems to be about fat already 'digested into' the body (assuming you're no cannibal), which is a different thing yet. DirkvdM 09:04, 15 October 2006 (UTC)

I was wondering (no, the following is not a joke. It is a half-baked idea that would never work) if human fat contains enough energy to be an alternative fuel source. I could have people eat until they are very fat, lipo the fat out, process it, and sell it for fuel. Tons of people would love getting paid to eat all day, and the fuel source would never run dry. THL 10:41, 15 October 2006 (UTC)

The food source might. 81.93.102.3 10:56, 15 October 2006 (UTC)

In 6 billion years, has food for animals ever run out? Maybe in localized areas, but now that humans have airplanes, that really isn't a problem. THL 11:02, 15 October 2006 (UTC)

Right, we could "lipo the fat out" of the passengers for fuel in flight!  --Lambiam^Talk 16:24, 15 October 2006 (UTC)

<--Besides, if food runs out fuel is the least of our worries. THL 11:03, 15 October 2006 (UTC)

1 gram of fat is 38 kilojoules of energy. Or 9 Calories (that's BIG CALORIE) or 9000 calories (that's small calories).

That's rendered fat. Unrendered will be fewer. Anchoress 12:00, 15 October 2006 (UTC)

Human fat is a terrible fuel source because you have to make it by eating other things. Any time you move up a trophic level in the food chain, about 90% of the energy in the source is wasted. Its much more efficient to use the things we eat as fuel rather than processing them through the human body. pschemp | talk 12:30, 15 October 2006 (UTC)

Well, I did say the idea was half baked and would never work. I was just curious how much energy was in fat so I could compare it to fossil fuel. THL 14:18, 15 October 2006 (UTC)

Protein and carbohydrates contain 4 calories per gram, and fat contains 9 calories per gram. Edison 20:05, 15 October 2006 (UTC)

This page may help too: [1] But regarding your original idea, it's pretty much equivalent to meat farming, except in that case we have the luxury of actually killing the animal. And meat farming is notoriously inefficient. The article environmental vegetarianism has some stats regarding how the efficiency (output per input) of meat is much less than of crops; these measure output in terms of protein rather than calories but you get the idea. Biofuel is a very sensible idea, but you want to use the crops more directly. See also comment from pschemp above. Arbitrary username 12:49, 17 October 2006 (UTC)

Much thanks everybody. I knew the idea would never work, and I wouldn't have the money to finance such an undertaking anyway. It was more of a curiousity than anything else. THL 22:50, 17 October 2006 (UTC)

Actually, there was a rather grisly case where human fat was used as a fuel source. The Nazi extermination camp crematoriums were mostly fueled by the burning of human fat, with just a little coal to get the process started on the first set of corpses. "Spontaneous human combustion" is also the burning of human fat, although some external heat sources is needed to get it started, so it isn't really spontaneous. This heat source can be quite small, however, such as a cigarette fallen onto the clothes of someone who died from a heart attack. The source, once fully consumed by fire, often can not be identified. StuRat 18:13, 20 October 2006 (UTC)

Wow. I can't really think of anything else to say. THL 22:35, 20 October 2006 (UTC)

Am I secretly gay?

While I am sexually attracted to women, sometimes I have wet dreams about having sex with 'chicks with dicks' (not so much transsexuals but women who have both a penis and a vagina), which usually involve me sucking or playing with cock at some point. I've started looking at dickgirl hentai online and found it sexually arousing. Does this mean that I have a homosexual streak hidden within me somewhere? I'm confused and I'm not sure what to do. --84.65.109.37 10:19, 15 October 2006 (UTC)

Most people have no sexuality focused on a gender alone, and it is quite possible to be different gradients of bisexual, in favour of either hetero or homo. I seem to remember a quite thorough statistics done on this topic alone, but it has evaded me, and I don't have any satisfying graph to show you. Who you are, very few but yourself hold any answer to, and if you don't, of course no one should claim to. 81.93.102.3 10:54, 15 October 2006 (UTC)

I would go talk to a psycologist. They may not hold the answers, but they can help you find them for yourself. THL 10:59, 15 October 2006 (UTC)

It depends on your definition of GAY. If you defined gay as loving people with penises, then you are secretly gay. If you defined gay as loving people who look like men, then you are not secretly gay. So make up your mind, what your definition of gay is and you would know what you are.

This may sound like a stupid suggestion - but have you ever actually stopped and asked yourself whether you are attracted to men? Just having wierd fantasies doesn't nessasarily equivalate to homosexuality. But if it's bothering you so much, a psychologist would be appropriate. --`/aksha 12:36, 15 October 2006 (UTC)

Many people find certain fantasies arousing that they would not be aroused by – and perhaps even find abhorrent – if occurring in reality. There is a tendency to define neat categories people's sexual orientation can be placed in – straight, gay, bi, fetishist, submissive – but reality is more fuzzy and fluid. The confusion is caused by inadequate categories. I see no reason to be worried unless your dreams start interfering with your social life.  --Lambiam^Talk 14:53, 15 October 2006 (UTC)

I wouldn't care much, since if you are actually attracted to women you are by definition non-gay, since homosexuals are those who are attracted (just or "mainly") by their own sex. I think it's quite normal for people to have strange sexual fantasies apart from their main definition of sexuality. So my opinion is that you are not secretly gay.

How is your sex life? If this question is uncomfortable I understand. Remember, you are anonymous, none of us are going to know who you are. THL 17:17, 15 October 2006 (UTC)

Don't worry about it, we all have a few skeletons in the closet. StuRat 20:32, 15 October 2006 (UTC)

Are they gay skeletons? Hyenaste ^(tell) 20:34, 15 October 2006 (UTC)

Well, all skeletons are rather limp wristed and light in the loafers, aren't they ? :-) StuRat 03:03, 17 October 2006 (UTC)

I'm guessing you are probably still pretty young, you've gone through puberty and your a big bag of hormones that your body simply hasn't gotten used to yet. I don't think you have anything to worry about, there are things I had wet dreams about I wouldn't even admit anonymously ;) . The worst thing you can do is think you are a weirdo or something, everyone goes through things that seem strange. Don't worry about it, the wet dreams will stop (sometimes I wish they didn't, they can be more fantastic then anything you could do in real life!! :D ) enjoy it while you can. Your mind will settle and it will start making sense before you know it. And whatever happens, there's nothing wrong with being gay. Vespine 03:57, 16 October 2006 (UTC)

when I was younger I had somewhat similar fantasies. You may be imagining doing things like that to other people because you want that done to yourself. THL 05:22, 16 October 2006 (UTC)

You are homosexual if you are also a chick with a dick. If you are clearly male or female biologically, then you are having pansexual fantasies. (Not all people are clearly 100% male or female physically).

You can't control your dreams and fantasies or sexual attractions anyway, so you must learn to accept them. They may also change. - THB 08:29, 16 October 2006 (UTC)

I was told once by someone who is usually knowledgable on such things that interest in transexuals who appear as women with penises is predominantly a fantasy of heterosexual males. Not sure why. Dragons flight 08:50, 16 October 2006 (UTC)

I talked to a psychologist about it when I was having them; he said that I was having them because that was something I wanted done to myself. It was interesting. THL 13:11, 16 October 2006 (UTC)

What kind of frog is this?

I found a frog in a creek a few miles inland from the Connecticut shore, and took a picture of it. What kind of frog is it? grendel|khan 11:36, 15 October 2006 (UTC)

Leopard frog. alteripse 12:50, 15 October 2006 (UTC)

I don't see the "distinct light-edged dark spots across the back" in the Flickr picture that should make them recognizable according to our article.  --Lambiam^Talk 14:29, 15 October 2006 (UTC)

Look at the choices: [2]. There are a couple of species of leopard frogs, and they are one of, if not the most, common green frogs with dark marks in the eastern US. I suspect the light borders are not universal in all lifestages or variations, but do not claim unusual expertise in frog identification. alteripse 14:52, 15 October 2006 (UTC)

In any case, I still don't spot them, just as I wrote. Maybe the text of our article should be adjusted (by an expert). Or perhaps Grendelkhan discovered a new species :)  --Lambiam^Talk 14:58, 15 October 2006 (UTC)

(edit conflict) From this (same as Alteripse, but cam across before your post), you have 10 species to choose from. This frog is missing a few characteristics found in the Leopard Frog, particularly the large spots and dorso lateral line. I would say that it is the Green Frog (Rana clamitans). The green above the lip is a characteristic common in Green Frogs. Thanks. --liquidGhoul 15:00, 15 October 2006 (UTC)

Can`t be a leopard, I don`t think. Feet appear to be too long for leg length? Just a guess. 152.163.100.74 18:33, 15 October 2006 (UTC)

I'd go with the (boringly named) Green Frog, based on the pictures, perhaps a young one. The leg stripes and back pattern look pretty similar to this little guy's. --Fastfission 20:12, 15 October 2006 (UTC)

Yep, it is a Green Frog (Rana clamitans).--Tnarg¹²³⁴⁵ 22:24, 15 October 2006 (UTC)

"Absolute hot"?

Everybody knows about absolute zero. But I've been wondering, could there be such a thing as "absolute hot", in which all the particles are moving at c? Would this be a temperature that you could measure in Kelvin? --The Lazar 15:22, 15 October 2006 (UTC)

Negative temperature might help (I don't quite understand this level of physics). I would assume it would be infinite temperature although you can have things hotter then infinite temperature so... Nil Einne 15:35, 15 October 2006 (UTC)

According to the special theory of relativity, only massless particles (photons, gravitons if they exist) can travel at c, only at c and nothing but c. Particles having invariant mass remain below c. From the formula for (relativistic) kinetic energy you can compute how close to c theory allows you to make them go for any amount of energy that you put in:

$v=c\,{\sqrt {1-{\frac {m_{0}c^{2}}{E_{kin}+m_{0}c^{2}}}}}$.

If the kinetic energy is very large, you can approximate that by

$v=c-{\frac {m_{0}c^{3}}{2E_{kin}}}$,

which is obviously less than c.  --Lambiam^Talk 16:58, 15 October 2006 (UTC)

Not really. No massive particle can actually reach the speed of light. But could they all have the same very high speed v that is only a little bit smaller than c? I'll discuss this questions.

The main point to understand about temperature is that kinetic energy is heat only if the particles (let's talk about a gas for now) all move in random directions. If they all moved in the same direction, it would just be wind. (We discussed this only a few days ago in the Science Reference Desk. You may want to scroll up a bit for that.) Now, if all particles have the same temperature, but different direction, they will all speed outwards, and you have no longer a volume filled with gat but rather a spherical hollow shell of gas that expands. (The picture I have in mind is supernova remnants. Or were you imagining a gas in a box? Let's imagine that all gas particles have the same velocity v. The particle scatter, i.e., they bump into each other an exchange energy, i.e., if one particle bumps from behind into another one, the rear one loses speed and the front one gets even faster. (Go and drive bumper cars to see what I mean.) So, after a short while (the so-called thermalization time) the particle have no longer all the same velocity, but rather, the velocity is distributed after a specific formula, the Maxwell-Boltzmann distribution. Only then does it make sense to say that the particles of the gas have a temperature, and this is the temperature according to the M-B distribution. The temperature can get arbritrarily high, only that after a while, the Maxwell-Boltzmann formula becomes wrong: Even for high energies, the Boltymann formula correctly tells us, what kinetic energy a particle has with which probability, but in order to see how fast it is, we must not use the usual $E_{kin}=1/2mv^{2}$ because this formula only holds for velocities v much smaller then c. Rather the formula from special relativity has to be used, that tells us how the kinetic energy can become larger and larger without the particle ever reaching the speed of light, because its mass also gets larger ad larger. (See mass in special relativity).

Hence, there is not maximum temperature. Negative temperatures don't really count IMO because they are a rather artificial concept. I think the article explaind it but if you have questions, ask. Simon A. 17:08, 15 October 2006 (UTC)

Negative temperatures are not an artificial concept; actual physical systems have been observed at negative temperatures for minutes at a time. To answer the original question, the hottest possible temperature is −0 K; it occurs when a system is in its unique highest energy state. But a gas does not have such a state, and there is no relativity involved. Melchoir 19:41, 15 October 2006 (UTC)

Ok, I take the bait and explain. Let us first move away from a gas to an idealized spin system, i.e. a solid whose consituents (atoms) store their (thermal) energy not by vibrating (i.e., no phonons in my model) but by being excited. Furthermore, we do not allow for arbitrary excitations, rather, there is a amximal energy, that each atom can store. So, let us say, that an atom can store either no or one quntum of energy. You might say, that this sounds like an idealization far from reality, but there are situation where all only those parts which I did not just "idealize away" are relevant for a certain specific discussion. And only then may we talk about negative temperatures -- and this is why I called it "somewhat artificial". The standard example for such a situation is a laser medium, and one might encouter it also when discussing magnetism. In this situation, the amount of energy stored in an atom (or [quasi-]spin, to use more correct terminology) is one of a discrete, finite set of values E₀, E₁, ..., E_n,, and the probability $p(E_{i})$ that a given atom has one of these values is proportional to the Boltzmann factor $e^{-{\frac {E_{i}}{kT}}}$. This means, that if the system is thermalized (i.e. at equilibrium), the probalities $p(E_{i})$ are such that they fullfil this formula with T being the ambient temperature. Now, we can engineer the system such that the probilities do not follow this law, for example by making some mechanism that puts most of the quasispins into the state $E_{2}$, and as long as we keep this mechanism switched on, it would be incorrect to assign a temperature to it. Now, it is not so easy to devise such a mechanism and it turns out that often, we cannot deviate much from the formula. For example, if we have only two energy levels and shine very bright light of the right frequency onto it, we can pull the atoms to the higher level but they will keep falling down (see Einstein's theory of the photo-electric effect and the James-Cummings model) to the lower one, so that at most half of them are in the upper one. And this situation can be described by the Boltzmann formula by putting T to infinity. There is a more clever thing, called population inversion and being the basis of the laser, where the upper state has higher probability as the lower, but in such a way, that the Boltzmann formula gives the correct ratio if one plugs in a negative T. This is then called a negative temperature.

Now, why is this not a real temperature? Well, by definition, a body A is hotter than B if B gets warmer when brought into contact with A. So, if A is now our quasispin system with the negative temperature, of which we have learned that it is hotter than all positive temperature, should it now not heat up body B? It does in fact, if body B (our thermometer) is the same idealized system of quasispins. But statistical physics stresses that temeperature is athing that can be defined universally: Every object, if leftalone long enough in order to thermalize, will aquire a temperature which can be compared in a definite way with any other body with at thermal equilibrium. (By comparing, I mean, we can watch, whether heat flows from A to B, or vice versa, which tells us which one is hotter.) This is often called the zeroeth law of thermodynamics. Now, as body B is any system, we have to take into account all the degrees of freedom that we "idealized out" before. And if B is sufficiently hot, we will see without doubt that heat flows from B to A, showing that A is not so hot, although it had allegedly a negative (more than infinite) temperature. Simon A. 21:59, 15 October 2006 (UTC)

This too is wrong. If A has any negative temperature and B has any positive temperature, and the two are brought into thermal contact, heat flows from A to B. If heat were to flow from B to A, then both systems would be decreasing their entropies! Melchoir 22:10, 15 October 2006 (UTC)

Exactly what I am saying: If A has truely negative temperature, then heat would flow from A to B, reagrdless how high the positive temperature of B. Now I say that empirical evidence supports the following claim: For every body A, a body B can be prepared that is so hot (has so large positive temperature) that it would let heat flow onto A, even if A were in a state which some may call having "negative temperature". Hence, it is untenable to say that A's so-called negative temperature is hotter than any positive temperature. If you disagree, you have to cite an example for an object A that is able to transmit heat onto any object B with positive temperature. There is no such thing, or do you claim otherwise? If so, I'm curious to hear what this might be. Simon A. 22:53, 15 October 2006 (UTC)

Nuclear and electron spin systems. If you want emprical evidence, go track down the Physical Review references cited by Kittel and Kroemer. Or perhaps you'd like to expand upon your own "empirical evidence supports the following claim"? Melchoir 23:41, 15 October 2006 (UTC)

Look, habe you read my longer text above? I know, that nuclear and electron spin systems are the standard example. Let's take the example of nuclear spin systems. The levels in nuclear spins correspod to very low energy, typically in the microwave range. So, you have some bulk of matter and put it into an NMR apparatus. Using clever pulse sequences, you achieve population inversion. Taking the Boltymann formula you say, "Population inversion means negative teperature. My stuff is hotter than enything else in the world." To rove, you put another lump of the same kind of cold matter next to it, and, hey presto, the population inversion spreads over, warming up the other piece a little bit. Actually, this last part of the experiment will turn out quite difficult in practice, and most importatly, it will work at all, only if all non-spin degrees of freedom are frozen out or decoupled in both samples. I hope you know what I mean be "frozen out or decoupled" because that is the crucial assumption that physicists imply when they talk about negative temperature. And that is the problem, too: Proper temperature is defined with all degrees of freedom taken into account. So, to prove you wrong, I caome to your lab and est your population inverted sample, but not using another one with the aformentioned property but rather a piece of hot nearly-melted iron, which I put with tongs next to your sample. Now, do you seriously claim that my iron will not simply melt down or destroy your sample, but instead get even hotter?

Please look up your references yourself. I'll see if I find a good exaple later today. But I'm sure you'll notice that they compare the temperature of their samples with other samples of the same kind and not with any arbritrary body as required by by the zeroth law. You'll also notice that they nowhere claim that their sample would heat up any other samples. Typically, in such papers, the language is not careful enough as to mention the reservation about the unusual notion of temperature employed, because this is assumed to be knwon by the reader. Simon A. 07:23, 16 October 2006 (UTC)

Well, how weakly coupled do two systems have to be to merit separate temperatures in your book? Is an hour's relaxation time between spin and kinetic degrees of freedom not long enough? What if we achieve a day? A year? How unphysical are you willing to make your demands?

When my spins achieve equilibrium with any conventional probe -- your iron, the lattice they live on, whatever -- they will fall from a majority high-energy state to a majority low-energy state. Conserve energy. Melchoir 08:12, 16 October 2006 (UTC)

I'd agree, an hour is long enough. So after a n hour, the coupling with the lattice (the phonon degrees of freedom (DOFs)) is established, they fell down and gave their enrgy to the lattice DOFs. So, it is justified to say that be spin subsystem was hotter than the lattice sub-system, because energy has flown from the spin DOFs to the phonon DOFs. Agreed. Also, we may argue that as long as we keep within this framework, the spin DOFs had indeed a higher temperature, and a negative one. But this is only correct as long as we stay in a finite state system (as you have pointed out yourself above). If I put the sample into a really hot oven, it melts, i.e., leaves this subspace, and takes on heat. This means that the sample as a whole was cooler than the oven.

But now we're getting to the core of our dispute, finally: I said that "in my book" a temperature is a property of a body in equilibrium, and if I put a very hot second body next to it, the second body will let heat flow to the first, showing that it is cooler. "In your book", you allow to ascribe temperature to subsets of the DOFs within a single sample. You suggest to assign a different temperature to the spin DOFs and the lattice DOFs, because they couple only weakly. Correct, this is what one likes to do in NMR physics and then, negative temperature make sense. But this is a generalization of temperature. To summarize: (i) There is no contradiction in the claims of your last post and my "empirical claim", because you talk about heat flows between different DOFs of the same system and I talk about heat flows between seperate bodies, and asked for an example of that kind. If you in fact claim, that there is a physical example of a body or DOF subsytsem with negative temperature that can let heat flow onto another, conventional body (and not just onto this body's better coupled DOF system), then I ask for an example. Otherwise, (ii) we agree and only use different terminology: While I claim that the usual definition of temperature requires the different DOF systems within one body to thermalize and consider metastable states with thermalization only with DOF subsets as a generalization of temperature, you don't see it necessary to split this off as a generalization. The reason why I see it as a generalization is that we lose the validity of the following axiom: When a hotter body is brought in contact with a cooler one, heat will always flow from the hotter to the cooler (which becomes untrue in the case of your "hot" negative-temperature spin system next to my hot (but only positive temperature) piece of iron). Simon A. 11:06, 16 October 2006 (UTC)

But you don't lose any axioms. Your experiment, at best, involves three systems with their own different initial temperatures: the iron (warm), the sample's spins (hot), and the sample's other DOFs {cold). At no point is the iron exclusively in contact with the spins, so you are not observing the heat flow between them. You might as well pour 0°C water on a frozen-over lake, watch it freeze, and then complain that the lake floor is only above zero in the sense of an axiom-breaking generalization, because it couldn't heat up your probe. Oh, never mind the layer of ice between them. Melchoir 18:00, 16 October 2006 (UTC)

physics

tthere r 8 identical balls each having same charge & energy E ,if they r united to form a sphere.wat is the energy of this new sphere/

How do you unite balls to form a sphere? Do you squeeze them? Otherwise you get something like this. What is the nature of the energy they have? Are they spherical charged batteries? Flywheels? If they have the same electrical charge, you may need energy to bring them together. Apart from that, the law of conservation of energy says that the energy of the combined system should equal the sum of the energies of the original individual systems.  --Lambiam^Talk 17:14, 15 October 2006 (UTC)

Is this, by any chance, an incorrect analogy for atomic nuclei? ☢ Ҡi∊ff⌇↯ 17:18, 15 October 2006 (UTC)

Triple point revisited

I read with great interest here 1.11 "Triple Point of Water", and got to thinking/wondering: What if we were to think of the problem using a single molecule of water, or perhaps better 3, single molecules of water...Can each molecule be in a different state simultaniously, and separately? Can one actually "have" a single frozen molecule of water? I would think that no matter what the temperature/pressure, a single molecule of water would ALWAYS be in the gaseous state. Is this true? 205.188.116.74 17:05, 15 October 2006 (UTC)

The various phases (solid, fluid, gas) are properties of a collection of molecules. It is meaningless to ask what phase an individual molecule is in.  --Lambiam^Talk 17:16, 15 October 2006 (UTC)

Decrease in Sexual Interest?

Does anyone know if pornography can cause a decrease in sexual interest, desensitivity to sex, and callousness towards intimacy and sex? I'm a really young guy, and I think porn may have caused some disinterest towards sex and woman when previously I was all about them. —Preceding unsigned comment added by The Truthish (talk • contribs)

If one takes into consideration how violent games can cause procedures to be learned, or arguably desensitivity to the consequences that violence or killing may cause, then there are limited reasons to say the same won't apply for pornography. Still, I only think that massive amounts of SEX will cause desensitivity to sex - and watching many pornographic pictures eventually builds up one's expectations to the standard of the contents of these pictures. Being a virgin myself, I am of course no authority. 81.93.102.3 19:22, 15 October 2006 (UTC)

I think it might raise your expectations to an unobtainable level so that only women who resemble porn stars would excite you: "Geez, I can't even see your ribs your so fat !". StuRat 19:34, 15 October 2006 (UTC)

Anyway, if you stop masturbating to the porn for a couple of weeks, you'll be fine. THL 19:36, 15 October 2006 (UTC)

I haven't heard of any studies that show a correlation. As far as your own personal experience, I think that that probably would've happened even without the porn. You've become more mature, is all. Ƶ§œš¹ _{[aɪm ˈfɻɛ̃ⁿdˡi]} 22:04, 15 October 2006 (UTC)

Desensitisation is probably temporary.--Light current 00:06, 16 October 2006 (UTC)

Probably for the same cause and reason that orgasm creates sexual satisfaction. — X [Mac Davis] (SUPERDESK|Help me improve)04:27, 16 October 2006 (UTC)

Pornography does have the potential to do as you are saying. The article is a bit lacking in quality, but have a look at pornography addiction; also sexual addiction. BenC7 01:36, 16 October 2006 (UTC)

Well, the article says: "There is considerable dispute about whether "pornography addiction" actually exists, and if so, whether it has harmful effects." Or is it the presence of this statement that makes BenC7 state that the article is a bit lacking in quality? Even if you believe in such an addiction, it has to rise to a level that can be called obsessive, interfering with the rest of your life. The eager consumption of porn by a young person is fairly normal and can hardly be called an addiction.  --Lambiam^Talk 01:43, 16 October 2006 (UTC)

Alright, I may seem young and childish, but I'm an old fart and have been around the block a few times. It is temporary, just stop masturbating to the porn for a couple weeks whenever you feel this way, and you'll be fine. THL 05:18, 16 October 2006 (UTC)

It's not the porn itself, it's your frequent masturbating. Hands off. Or at least this would be my guess; I've never masturbated myself. -THB 08:47, 16 October 2006 (UTC)

HA HA! 90% of people admit to it. THe other 10% lie 8-)--Light current 13:51, 16 October 2006 (UTC)

what genes are in a genes pair

what two genes are in a gene pair??

The "genes" in a gene pair aren't genes at all; they're alleles. --David Iberri (talk) 19:47, 15 October 2006 (UTC)

Well, they may be (and usually are) DNA sequences that code for a gene, and then it is reasonable to call them "genes".  --Lambiam^Talk 22:39, 15 October 2006 (UTC)

There could be many Genes found in a pair of jeans (hopefully not all at once), for example, Gene Simmons. :-) StuRat 18:34, 16 October 2006 (UTC)

Identical alleles are found in what type of gene

Identical alleles are found in what type of gene?? Thanks

I expect you are interested in understanding the difference between hemizygosity, heterozygosity and homozygosity. Rockpocket 20:27, 15 October 2006 (UTC)

Science Fair

I am doing a science fair project for my school. The title of my project is: What foods attract ants? I need help on finding an If and Then hypothesis and a problem for my project. The project is very simple. I put differnt kinds of food, in different containers. I study which containers have the most ants around it, how long it takes for the ants to get to the food,and how long the ants will stay there. I know that the ants will probably go to the sugary foods. Bu I still need to write a If and Then hypothesis and a problem. If you could give me a suggestion, or any help with the project I would be very thankfuland very glad. -Sarah Baker

Okay, I think "If and Then" means your teacher wants you to include the reasoning behind your hypothesis in the complete statement. You predict the ants will "go to the sugary foods", but why did you make that prediction? What causes the ants to go to the sugary foods? For more information, see Writing Hypotheses and Writing a Hypothesis. —Keenan Pepper 23:26, 15 October 2006 (UTC)

Why are you using different types of containers? Usually you want to only change one variable at a time (i.e. the food), not two of them. How will you know what effect is due to the containers and what effect is due to the food type? I would make everything equal except for the food type. I would also try and distribute the foods semi-randomly (roll some dice?) to make sure that your bias going into it that the sugary foods will be more preferred does not lead to you to unconsciously make it easier for the ants to get to that food (i.e. by putting it closer to a known set of ants). In fact it would be ideal if you made the containers so that you the experimenter could not see what type of food was in them until after you had made your observations — that way there is little chance that your expected outcome will bias your observation (after all, maybe ants actually prefer turkey over candy — who knows? I've never really given them the option).

She said: "different containers", not: "different types of containers". You don't want to put all the different foods in the same container.  --Lambiam^Talk 01:13, 16 October 2006 (UTC)

The easiest "If/Then" statement you can do for this is simply, "If ants are given a choice of many types of food, Then they will prefer foods with high levels of sugar in them." --Fastfission 00:58, 16 October 2006 (UTC)

I agree that this may be meant by "If and Then hypothesis". But since you can't test all types of food, the generalization is probably not warranted. Perhaps the ants really love canned tuna (some actually do), or lasagna, much yummier than sugar, only it wasn't included in the experiment. Then you jumped to the wrong conclusion.  --Lambiam^Talk 01:13, 16 October 2006 (UTC)

I can think of much better ideas than what food attract ants. How about the relative attraction of fatty food versus fruits and vegetables for obese humans. You offer to pay for 1 days of fatty food or X days of fruits and vegetables. Find the variable X where it is in equilibrium with 1 day of fatty food by interviewing lots of obese people. Find the mean and standard deviation.

Why stop at fruit and vegetables? You can build up a hierarchy of food attractiveness for obese people. 202.168.50.40 01:02, 16 October 2006 (UTC)

If you want to be really scientific, you have to be specific about the species of ant (not all ants species have the same food preferences) and make sure, if your experiment runs over several days, that you put out the food each day at the same time (some species have a fixed daily schedule of what time to do scouting and what time to start fouraging).  --Lambiam^Talk 01:13, 16 October 2006 (UTC)