Wikipedia:Reference desk/Archives/Science/2007 March 31

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March 31

Comparing European Magpies with Black-backed Gulls again...

The pairing up and nest-building has started again for both species. Question: Why is it that the magpies raise more chicks per year than the gulls? The magpies here typically raise six or more chicks to fledging, whilst it's rare for the gulls to rear more than two. Gulls live longer than magpies (15+ years vs. 5-ish) - does this have anything to do with it, or is it the case that young magpies are more vulnerable than young gulls? From what I've seen around here, the majority of the magpie chicks survive to join the (ever growing) flock. Both species aggressively defend their young and the flock in general from predators. --Kurt Shaped Box 00:08, 31 March 2007 (UTC)

(Answer without knowing any more facts than what you've said) The obvious answer (guess) is that the birds raise as many chicks as they're likely to be able to find food for. However, it could be a case of r vs K selection, e.g. if magpies could expect a larger number of their chicks to die young they may have more to compensate, even though they couldn't expect to feed them all, while seagulls have a more concentrated effort in raising their chicks.. But food-limitation is the simplest explanation. —Pengo 00:59, 31 March 2007 (UTC)

I would say the life-span is the critical factor. That is, gulls, living longer, can afford to take their time and put their energy into raising a small number of offspring properly each year. Magpies, on the other hand, are in a race to pass on their genes before they die, so much have more offspring each year. This, in my opinion, causes the higher chick mortality rate in magpies, as they must each start out smaller, and each get less attention (and, more importantly, food), from the parents. StuRat 05:50, 31 March 2007 (UTC)

Indeed. To continue on this, if many magpie chicks are surviving to adulthood, this may simply be a sign that the magpie population in your area is currently below its carrying capacity, and thus growing. In fact, in a stable population, by definition, only two offspring total will survive to reproductive age for each breeding pair over their entire lifespan. If there are any more, the population must necessarily grow. Indeed, this is characteristic of r-strategists; they'll rapidly adapt to changes in the carrying capacity of their niche. —Ilmari Karonen (talk) 21:31, 2 April 2007 (UTC)

science project build a volcano

My 11 year old grand son needs instructions on how to build a volcano for his science project.Do you have any instructions? Chicago Grandma —The preceding unsigned comment was added by 69.3.101.156 (talk) 04:08, 31 March 2007 (UTC).

google science fair volcano. Approximately 964,000 hits, mostly useful. If you need further help after looking at a few of these, please ask a more specific question. Good luck in the science fair. As a recent judge in a high school science fair, I reccommend that your participant's project should focus on a particular aspect of whatever phenemenon your "volcano" exhibits. -Arch dude 04:39, 31 March 2007 (UTC)

It would also be cool to have a couple of model villages, and experiment with known or imaginary methods of diverting the "lava", then demonstrate them. --18.214.0.137 15:22, 31 March 2007 (UTC)

An actual volcano? Might be a little too much to ask of an 11 year old? 80.229.228.229 20:30, 31 March 2007 (UTC)

All you need to do is puncture the Earth's crust, how hard can that be ? :-) StuRat 00:43, 3 April 2007 (UTC)

Excellent Googling by Arch Dude. I was going to suggest a hollow cone a hole in the top with marmalade flowing down the outside (for the magma), and some dry ice inside to simulate smoke!. Now I wont! —The preceding unsigned comment was added by 88.111.79.170 (talk) 01:27, 3 April 2007 (UTC).

And if you're going to have marmalade lava, might I suggest melba toast "pumice" around the volcano...leading to a nice snack afterwards ? StuRat 01:41, 4 April 2007 (UTC)

Bullet in the air?

If someone shot a bullet into the sky , would it come back down or would it go into space?? —The preceding unsigned comment was added by 74.102.217.142 (talk) 04:58, 31 March 2007 (UTC).

It would fail to reach escape velocity, and come back down. —Pengo 05:20, 31 March 2007 (UTC)

A rifle bullet can travel at 1200 meters/second[1] whereas the escape velocity of the Earth is 11,200 m/s. (And "larger guns" can fire at 1500 m/s) —Pengo 05:28, 31 March 2007 (UTC)

Also, I don't even think it's possible to fire an object from the surface fast enough to leave orbit, as the object would slow down due to air resistance. Thus, the initial speed would need to be far higher than 11,200 m/s for the object to still be going at escape velocity after it clears the atmosphere. An object moving at such a high initial velocity in the air would likely burn up in the atmosphere. Thus, all rockets launched from Earth provide thrust until they clear the atmosphere, instead of relying on a high initial velocity to carry them clear. StuRat 05:37, 31 March 2007 (UTC)

There seems to be some confusion about escape velocity - that's the velocity you need to escape from an earth orbit and go off into the sunset, or wherever. To get 'into space' you need a bit less than that (nearer 7800 m/s, to get into an Earth orbit and stay there) but that's still much, much faster than can be achieved by the sort of gun that shoots bullets, and doesn't take account of drag or the potential energy you have to gain to climb to orbital altitude (~100km) against gravity. Project Babylon is an example of the sort of gun you need to shoot things into orbit. --YFB ¿ 11:14, 31 March 2007 (UTC)

This reminds me on the Columbiad. Verne calculated the parameters quite accurately, we only should find a suitable material that wouldn't melt. Would the Space Shuttle's armor survive it? --V. Szabolcs 14:27, 31 March 2007 (UTC)

See Project Babylon and Project HARP. People have tried, and it's certainly possible, just not all that practical for most payloads. --bmk

Maybe an enormous ring of superconducting magnets similar to a particle accelerator that could fling satellites into space would change that (see NewScientist story).--JLdesAlpins 16:14, 31 March 2007 (UTC)

I read some speculation recently where a scientist or engineer who worked on one of the underground nuclear tests in the 50s was suggesting that the first object into space was, in fact, the manhole cover from the borehole down which was placed the nuclear device. Apparently, some back-of-the-envelope calculation suggested that there was enough pressure from the blast to launch the manhole cover with six times escape velocity![2]

Atlant 12:11, 2 April 2007 (UTC)

Specifically, this was Operation Plumbbob. Although the calculations suggested that, while the cover might well have been fast enough to reach space in theory, it was probably vaporized by atmospheric drag before it got anywhere that far. —Ilmari Karonen (talk) 21:46, 2 April 2007 (UTC)

Isn't an orbit where an object falls around the side of the earth, as it is going fast enough to get all the way around, and therefore an object in orbit would have to be travelling sideways, whereas anything fired streight up would just get into space and fall back down, unless you could get it close enough to the moon, which is very unlikely :) HS7 18:20, 1 April 2007 (UTC)

Correct, an object would need to be launched at an angle to achieve orbit. Rockets generally start off vertical, then tilt later on. StuRat 00:38, 3 April 2007 (UTC)

A rifle certainly isn't fast enough to get a bullet into orbit - but it's widely believed that it would be possible to build a gun that could. In fact, in the first US war against Iraq, it was discovered that Saddam Hussain was attempting to build such a 'supergun'. He had ordered parts for the weapon from lots of different companies under the guise of them being some kind of oil refinery parts in order that people wouldn't know what he was doing. One part of this supergun is in a museum in UK - I have a photo of it someplace. The bore of the gun was about a meter or so. You can read about it in our article Supergun. One suspects that he was planning to use it to launch nuclear weapons without having to develop intercontinental ballistic missiles. SteveBaker 04:33, 2 April 2007 (UTC) (PS: Project Babylon contains photos of bits of the cannon - including the section I saw at The Imperial War Museum in Duxford, UK.)

I could buy using such a device for short ranges, but not to fire objects into space, at least not until we find a way to remove the Earth's atmosphere. StuRat 00:36, 3 April 2007 (UTC)

see Project HARP and "A Brief History of the HARP Project".—eric 00:43, 3 April 2007 (UTC)

Pre-implantation Genetic Diagnosis

Can PGD be used to avoid children from inheriting Marfans Syndrome? If so, what are the risks involv

59.94.30.2 05:34, 31 March 2007 (UTC)

Have you read our preimplantation genetic diagnosis and Marfan Syndrome articles ? I don't know if they contain the answer, but they might. StuRat 05:42, 31 March 2007 (UTC)

They don't contain the answer. The answer is "yes". One article to consult for further details is Spits C, De Rycke M, Verpoest W, Lissens W, Van Steirteghem A, Liebaers I, Sermon K. Fertil Steril. 2006 Aug;86(2):310-20. Epub 2006 Jun 6. PMID 16756980 - Nunh-huh 15:25, 31 March 2007 (UTC)

Magnetic energy

Does it exist?If so, where can it be found?How does man make use of it? —The preceding unsigned comment was added by Invisiblebug590 (talk • contribs) 09:45, 31 March 2007 (UTC).

Have you read the Wikipedia articles on Magnetism, Electromagnetism or Electric motors? Nebraska bob 10:37, 31 March 2007 (UTC)

Also, check out Inductor, a neat device that man uses to store said energy! --bmk

But beware of popular pseudoscience pertaining to magnetic energy. Magnets are sometimes incorrectly viewed as a source of energy in perpetual motion devices, and magnets are ascribed healing properties in magnet therapy for which there is little if any scientific evidence. MrRedact 17:28, 31 March 2007 (UTC)

Thank you for catching this. There is certainly a lot of unfounded pseudoscience around involving magnetism.

That's for sure. There is one where a home made device spins a magnet around past your forehead and it was suppose to make me smarter or sleeper or my memory better but now that its running I forget which one. 71.100.167.232 02:39, 1 April 2007 (UTC)

Animal fat and Boric acid

Will animal fat disolve Boric acid (or will Boric acid desolve in animal fat)? Nebraska bob 10:33, 31 March 2007 (UTC)

I checked and could not find a quick answer. I suspect the answer is no. Esters of boric acid could be oils and fat soluble. GB 03:33, 2 April 2007 (UTC)

A Health Diet

Can anyone recommend any decent health diets (Not to be confused with weight-loss diets)? Nothing too controversial, but something 'tangible'. I mean it's all very well giving me a food pyramid - but what about TANGIBLE lists of things I can eat?
Particularly, I'm not a fan of bread (or wheat), or milk/cheese, and I'm worried that I eat too much meat - so basically if you coud recommend any 'tangible' health diet for someone like that, I'd appreciated it Rfwoolf 11:40, 31 March 2007 (UTC)

• Reduce or eliminate refined sugar and flour, junk food and fast food.
• Eat a variety of fruits and vegetables, try to hit 10 servings a day.
• Eat a variety of nuts and seeds.
• Eat beans and legumes.
• Eat cold-pressed oils, aim for monosaturates and unrefined nut oils.
• Eat unprocessed foods wherever possible.
• StuRat will recommend seafood, that's not on my list but I have no objection to it.

--Anchoress 11:44, 31 March 2007 (UTC)

And BTW I'm not advocating a vegan diet, but just listing the things you should try to eat for a healthful diet. Meat, dairy, whatever else you usually eat I'm not saying don't eat it. The two most important things for improving diet are a) reducing processed, fast, refined, and sugar-laden foods, and increasing fruits and veggies. Anchoress 11:47, 31 March 2007 (UTC)

Agree with the above recommendations (including fish, like salmon). Also, try to keep the salt low and water consumption high (add lemon juice to make it palatable). Have you tried grains other than wheat ? How about rye or pumpernickel breads ? Try spreads like hummus, tahini, and guacamole in place of mayo and sour cream. Also, don't eat anything fried; try roasting, boiling, or, where possible, steaming, instead. StuRat 23:57, 2 April 2007 (UTC)

Well thanks for that, I suppose I should have added that I'm not highy physically active and so eating for example an avacado - I don't know if this would be a bad idea if I have more than one a day? And what about fruit, should I fill myself up with loads of fruit? Anyways, thanks for your help. Rfwoolf

Avacados are excellent, especially if you use them in place of other fats. For example, you can skip the mayo on a turkey and avocado sandwich and make it much healthier. StuRat 00:02, 3 April 2007 (UTC)

Also be aware that although fruits are far better than refined sugar that frutis do contain sugar and for a person who is not physically active they can cause weight gain. In this regard the keyword is calories - as in watch those calories! You can do lots and lots of veggies, however, but remember calorie counting is the thing! Nebraska bob 12:34, 31 March 2007 (UTC)

v/v avocadoes etc, yes don't over-do it, but personally I am more concerned about nutrient density than calorie density. Avocadoes are high in calories, but they are also very nutrient dense, with lots of good fats and anti-oxidants. I wouldn't eat four a day, but I know a lot of people who make a point of eating one a day, and they're not fat. It's a question of - in part - what you're replacing it with. If you say to yourself, 'Oh, that avocado's too high in fat/calories, I'd better not eat it,' what are you eating instead? If it's broccoli florets and carrot sticks, maybe yeah, it's a worthwhile trade-off. But if it's a bagel with non-fat cream cheese or a bag of air-popped popcorn, or a taco or a hotdog, you were probably better with the avocado. Anchoress 12:55, 31 March 2007 (UTC)

And whaddaya know, check out our article on healthy diet. Anchoress 13:14, 31 March 2007 (UTC)

Also if you are not that concerned about calories the pecans in pecan pie are extremely nutritious! Nebraska bob 13:56, 31 March 2007 (UTC)

Thanks all! I should mention I found a useful website - www.sparkpeople.com (free) where you sign up and it has a calorie couter or over 10 000 foods and it assesses you BMI as well -so that's how I'm going to track my caloric intake. And thanksto Nebraska Bob and Anchoress for your input. Rfwoolf

Remove all meat (if you feel like protein go for seafood), remove all trans fats (aka hydrogenated oil), oats and granolas are good, lentils, unadulterated rices, olives, beans, refried beans, Kettle Chips or other similar products are healthy, potatoes in general are good, I find cheeses more palatable if they've been melted & browned, go for a variety of ethnic foods, particular Japanese (sushi), Greek, Italian, and Indian. Avoid fast food like the plague -- even Subway. Obviously fruits and veggies are good (and fruit juices), but realistically just eat them when you feel like eating them; an all-carrot diet just isn't sustainable. Above all trust your senses: eat what smells and tastes good. The one exception is trans fat: you don't taste it, and it doesn't cause problems until later, when your poor body tries in vain to digest it. Good luck and congratulations on wanting to go healthy, that's the most important step! Vranak

I reckon everyone here will disagree with me, but I think a diet with lots of sugar in would be healthy, especially if you want to lose weight as well, but you would have to be careful to have enough vitamins &c :) HS7 18:16, 1 April 2007 (UTC)

The internet, like a health food store, is full of well-meaning people with little or no understanding of nutrition. When in doubt, I recommend you take the advice of some reputable person or group over the advice of random people on the internet. You may even want to consult a doctor or nutritionist. There's not a lot that's automatically bad (trans fats may be a notable exception here), but too much of many things can turn out bad. The healthy diet article linked to above may be a decent starting point, but it looks like it could use some work, too. Friday (talk) 18:25, 1 April 2007 (UTC)

I agree with the above two posts: there's nothing (neccessarily) wrong with sugar, and health professionals may have better advice on healthy eating than a bunch of unknown people on the internet. But, I've heard, seen, and read a lot of supposed expert dietary advice which I find highly suspect, or at least overemphasizing a few particular points while having no 'big picture' idea of what a healthy diet looks like. A good rule of thumb is that anyone who doesn't look healthy probably doesn't know that much about healthy eating. Vranak

With all due respect to some of the posters above, the unhealthy effects of too much (refined) sugar and the health benefits of fruits and veggies are possibly the only two unassailable truths the nutrition world has stumbled upon (and I'm not trying to argue from authority, but nutrition is my field and I can dredge up the refs if necessary). While the occasional, moderate consumption of sugar isn't devastating, regular, moderate-to-high consumption of sugar is associated with so many compromises to good health that it must be considered one of the cornerstones of diet-related illness. Anchoress 21:12, 3 April 2007 (UTC)

Bladder size

I weigh about 95.25 kilograms and my bladder holds between 336 and 710 grams when I'm active and wakes me up at 726 grams. Is this average or is my bladder size bigger or smaller than normal? Nebraska bob 13:50, 31 March 2007 (UTC)

Our article suggests that the normal maximum volume of the urinary bladder is about 500 mL, and that most people feel a desire to urinate when it reaches somewhere around half that capacity. The various sources on this page suggest maxima ranging from 500 mL to as high as 1000 mL. TenOfAllTrades(talk) 15:14, 31 March 2007 (UTC)

What interests me is is: how the hell did you know all these weights so accurately? Also is your weight measured before or after micturation.

95.25kg is a rather precise figure, is it not? BTW, what time precisely does it wake you up? ;-)

Haha, it's probably based on a calculation estimate without regard for margin of error. [Mαc Δαvιs] (How's my driving?) ❖ 16:55, 2 April 2007 (UTC)

Close but... okay you can have a potatto! This always happens whenever I convert from one number system to another. Although the original measurement is not that precise the conversion results in a number usually to the 7th digit. In this case it was on 2. Becasue I consume so much water I usually wake up about every hour and a half to two hours depending also on what I eat. Typically I dump 6 to 8, containers that will hold at least 0.94635295 liters (32 oz) each per night. See what I mean? Nebraska bob 18:49, 2 April 2007 (UTC)

You should round to two significant digits, or 0.95 L, to match the two significant digits in 32 oz. By the way, remind me never to drink a 32 oz bottle of "lemonade" when I visit your house (are you related to Howard Hughes ?). StuRat 23:46, 2 April 2007 (UTC)

If I was to round to .95 liters then invariably someone would think I meant 32.1233214 US fluid ounce. Occasionally I do forget where I put one of the "cups" and stumble over it when I wake up. Then its a mad rush for towels and buckets of water to delute it an about 50 minutes before I'm done. Even then after a while there is a period of time when if you are close to that area of the carpet (on hands and knees looking for a contact then BAM the smell of urine will almost knock you out. Most spills though are in the bathroom just before a "cup" gets dumped. That's not fun either but at least the shower and a mop are nearby and cleanup is only about 10 minutes instead of 50. BTW we don't drink lemonade anymore at our house and don't ask me the reason why. Nebraska bob 04:19, 4 April 2007 (UTC)

Seriously though, if you drink that much and have to go so often, have you considered diabetes? —The preceding unsigned comment was added by 88.111.79.170 (talk) 03:06, 3 April 2007 (UTC).

Yes, I'm borderline according to my average glucose no matter how much I cut back on sweets - even replace them with artificial sweetner. Nebraska bob 04:23, 4 April 2007 (UTC)

flame temperatures

I'm having a little trouble following the entry on Flames, and my question is this: If the temperature of a flame goes up as the color of the flame moves along the spectrum towards white, where would that place something like Methane, which I think burns blue? Seems obvious that a blue flame would be on the other end of the temp spectrum, but I can't seem to verify this in the entry. Any help? Wolfgangus 14:32, 31 March 2007 (UTC)

I think that flame color has more to do with the fuels that are burning than the temperature of the plasma. It isn't a black body radiator. -- mattb @ 2007-03-31T16:52Z

The "flame color" section of flame says that the color depends on both the emission spectrum and the temperature of the flame. Different materials burning at the same temperature can emit different colors. -- Beland 22:13, 31 March 2007 (UTC)

Ok - thanks for the help. Wolfgangus 10:04, 1 April 2007 (UTC)

Psychology !!

Sir .. I wanted the notes for Rehabiliation of Psychology? please provide me .. as UPSC syllabus i needed ?

Thanzxs.....

• Um, Wikipedia is an encyclopedia, not your psychology professor... -- Beland 22:06, 31 March 2007 (UTC)

Sexing at Great Panda

Great Panda at Berlin Zoo

One question: is this is a male or a female Great Panda? Well, I would say male, but I've lost my naturalist exam in the Berlin Underground. Thanks a lot in advance for your help. --87.160.242.75 16:39, 31 March 2007 (UTC)

There seems to be a giant gaping hole in its crotch, which might mean it is a female, unless that is its anus. − Twas Now ( talk • contribs • e-mail ) 20:59, 1 April 2007 (UTC)

I didn't think pandas had sex any more

HELP PHYLLIS CREATE A SAMPLE TREE DESTINED FOR CUTTING?

I want to track exactly what would happen to birds and animals living in that tree. My focus is on animals living in forest destined for mass destruction. Post your aswers on my blog: <address removed>

Compiling for publication a Profile, I would appreciate information from math whizzes who would calculate numbers. How many birds might nest there? Squirrels? Bugs?

Some questions: The animals: Do the animals receive a warning of any kind that their tree is no longer safe? Do they flee in time? Do they find another home easily? What do they do when the first cut shakes the tree? The cutters: What do the cutters see when they first cast their eye on the tree? Do they look for nests? Do they discuss the destinies of its inhabitants? Look for them? Help them? Laugh? Cry? Ignore?

Every tree is a community. When it is cut, What happens to its residents? Where do they go? Are they forewarned? Do they run away and find a home elsewhere? Do they survive the cut and stay with the tree through thick and thin? Does someone care whether this particular critter lives or dies?

Q: What is happening on our tree as the signatures are being written? Q: What critters live in it and on it at that moment in time? Q: How many of each kind of resident lives on a tree? (example: RED ANTS - about 8,000 red ants live on a tree 71' tall and 2' in girth.)

How many cocktail napkins would our tree make? 20,000? How many toothpicks? How many stickies? How many stir sticks? Paper cups? Party hats? Newspaper pages? Party invitations. Coasters. Business cards. Flyers. Shelves. Hangers. Shingles. Tiles. Pencils. ETC. ETC.

THANK YOU FOR LISTENING. It's a one-time effort on my part to begin compiling a powerful picture that won't go away until the suffering it represents goes away. Phyllis contact: <address removed> —Preceding unsigned comment added by Niaih (talk • contribs) 19:46, 31 March 2007

Phyllis, I have removed your blog address, as it is probably not wise to show it on a forum as widely read as this one. I have also somewhat re-formatted and trimmed you contribution to highlight the questions within it. You may get some answers to your quantitative questions here. Gandalf61 20:40, 31 March 2007 (UTC)

Coke vs Speed

I took a drug and alcohol class in school and I was told cocaine has a higher high than speed, but does not last that long. Speed last longer but the high is not as intense. I was talking to someone and they told me speed has more intense highs, which is correct?

From purely anecdotal experience: they have different types of highs, I am not sure how you would qualify them are more or less intense or not—this strikes me in the end as a qualitative question that is not going to be easily answered even if there is quantitative data available on the line of neuroreceptors and the like. Cocaine is a jittery, adrenaline-like, aggressive high. Speed is a euphoric, "my mind is blasted into heaven", "I can really concentrate" sort of high. After doing cocaine you want to do more immediately (it has a harsh, immediate come-down) but if you don't get any more you feel okay after a little bit. After speed you want to do more in the long term (the come-down is more gradual, but you feel the need to feed it more, and as it is a lot cheaper in price you often have more of it to do) and it is incredibly easy to develop a more serious physical dependency.

Both are incredibly bad for your body and can lead to all sort of short and long-term damage to your nerves, your cardiovascular system, your teeth, and your nose; they are not worth it, in my opinion, as someone who has tried both during an ill-focused youth. I made it out of that scene more or less scratchless, by some miracle (and after one very close brush with the law), but I was more or less the exception: almost everyone else I knew there did not go on to accomplish very much and many ended up in jail in the long term. Both of the drugs pretty much have the immediate effect of turning you into an asshole at the very least; not exactly an attractive quality.

This is just my take on it—potentially too much of a soapbox for the reference desk—based on my experience. I'd stick to pot if it were me making the same choices all over again — neither of those two uppers really beat getting toked up and being completely contented eating an entire box of macaroni and cheese with some good friends. (Disclaimer: I no longer do anything but occasionally drink, and even then not very much. I guess I grew up.) --24.147.86.187 22:50, 31 March 2007 (UTC)

Coke's brutality is in the cycle: you ride a line for ten or fifteen minutes- then you spend the next 10 or so minutes trying to convince yourself you're still on that last line, then finally you go back to the plate. as the night goes on these minutes shrink while your lines get longer and longer. Meanwhile speed is a less-desperate affair. Guy above has it down well: coke=adrenaline-ish, speed intensely, hard-driving euphoria. additionally, a gram of good speed can last 1-2 days. a gram of coke: if you're lucky, an afternoon. Wolfgangus 05:55, 1 April 2007 (UTC)

Read a book, they are much better than either type of drug

Excercise and body heat

If its dangerous to have a high fever, why is it not dangerous to exercise? When I run for a long time (few miles), I feel as if I am way hotter than any fever I have ever had.

• The article Hyperthermia explains in some detail about the dangers of heat. In general, when you exercise, your body sweats and takes other automatic measures to keep your body temperature in a safe range. But if you say, exercise on a very hot day, it is certainly possible to get dangerously warm. Your subjective perception of your body's real temperature is not always accurate, but we don't have very much information about that which I can find at the moment. It would be nice if we had an article on the perception of temperature. -- Beland 22:20, 31 March 2007 (UTC)

See also Thermoregulation. -- Beland 22:22, 31 March 2007 (UTC)

I'm the most intelligent person in the world

I'm pretty sure I am. What can I do to prove it? --Taraborn 22:44, 31 March 2007 (UTC)

I could tell you, but that would sort of defeat the purpose. —Steve Summit (talk) 22:49, 31 March 2007 (UTC)

Deathmatch against Marilyn vos Savant. — Kieff | Talk 23:22, 31 March 2007 (UTC)

I'm too sexy for my shirt. --Right Said Fred 23:37, 31 March 2007 (UTC)

If you're such a genius, why do you have to ask? --24.147.86.187 00:01, 1 April 2007 (UTC)

That's easy to prove. Just win a couple of Nobel Prizes and a Fields Medal. There shouldn't be any doubt after that. -GTBacchus^(talk) 00:23, 1 April 2007 (UTC)

I wouldn't say prizes are any better measure of intelligence than are IQ tests. There's a lot to be said for environmental factors. Plus, I think it's rigorously impossible to "prove" that you're the most intelligent person in the world without meeting every person in the world and matching wits with them in some universally unbiased intelligence test. Failing that, I think you might have to settle with the lesser (but still illustrious) title of "most egotistical person in the world". -- mattb @ 2007-04-01T00:44Z

LOL well said Matt. --Bmk 01:16, 1 April 2007 (UTC)

Matt, I wouldn't say prizes are the "best" "measure" of "intelligence" at all. However, my remark above is what I would say to somebody asking how they can prove that they're the "most intelligent person in the world". That person doesn't need an answer, they need perspective. -GTBacchus^(talk) 02:04, 1 April 2007 (UTC)

The question is based on a very weak proposition, namely, that a relative ranking of the human population of Earth by IQ (or whatever quantifiable measure you personally choose to determine "intelligence") would necessarily represent a total ordering.

This ranking would have to be antisymmetric, transitive, and total for a "most intelligent" to even be definable, let alone provable. For example, if Alice > Bob > Charlie then it must follow that Alice > Charlie (transitivity). That means that Alice beats Bob on every dimension of "intelligence" implies Alice beats everyone on every dimension of "intelligence". All that would be necessary to demonstrate your question is meaningless would be to construct a head-to-head "intelligence" measure in which Charlie beats Alice. Even if Alice won the Nobel and the Fields, Charlie could beat Alice at a single game of Go and the whole scheme goes down the crapper. dr.ef.tymac 01:29, 1 April 2007 (UTC)

If youre so smart, ask yourself the question I do every day: "Why aint I rich?"

If you waste your time on that, then Taraborn is at least smarter than you, but then I suppose that's not saying a lot. DirkvdM 18:20, 1 April 2007 (UTC)

Reduce an infinite number of equations having an infinite number of variables with an infinite number of states to minimum form instantaneously. Nebraska bob 01:46, 1 April 2007 (UTC)

Ahh, it's so easy to disprove. Since I know how to prove whether you are the smartest person in the world, that makes me smarter than you. Ergo, you are not the smartest person in the world. Pretty logical. --Tbeatty 02:07, 1 April 2007 (UTC)

If you were really that intelligent, you would understand that intelligence is task-specific, so to speak of 'general intelligence' in any sort of serious way denotes a clear lack thereof. Vranak

Ah, but you are rich. In fact, if you can even afford Internet, you are richer than about 80% of the world. I can send you a link if you want, to see how lucky you really are. Also, you should try searching for an IQ test, hopefully one that does not require any personal info. I can send you a link if you want. Also, just because you're a wikipedian does not automatically mean you're smart. Well, then again, absense of evidence is not evidence of absence, I hope that isn't a copyrighted quote, and my point is, just because there's no evidence that you're very smart, doesn't mean you aren't. Hope this helps. AstroHurricane001^{(Talk+Contribs+Ubx)} 14:52, 1 April 2007 (UTC)

You could start with not asking any more stupid questions. :) DirkvdM 18:20, 1 April 2007 (UTC)

Who you calling stupid? 8-)

Performance superlatives are pretty hard to prove in a meaningful way. Take the last World Cup, for example. The fact that the Italians have won the final game does not mean in any way that they are the best football team in the world. Their world championship title only means that on July 9, 2006, at the end of the game, the Italians had a higher score than the Frenchs (incidently, at that very same moment, the Frenchs were stronger at headbutting). The score could have been totally different had the game being played the day before or a week after. Or say, is Napoleon the greatest general of all time? Had it not rained so much in the night of June 18, 1815, the Empereur could have ruled the whole world instead of rotting on a desolated island. Yet, if you ask an Italian football fan or a bonapartist, they will say that their object of reverence is "the best" at whatever. Therefore, to answer your question, gather a fan base that roots for you, and for them, you will be the most intelligent person in the world.--JLdesAlpins 19:49, 1 April 2007 (UTC)

Exactly. The 'best' (or 'most') superlative shows a high degree of vanity on two levels: the first is that a person using the word thinks they can actually make such judgements and that they are permanent, objective, and factual. Second, it shows an underlying insecurity, as whoever uses the word obviously wants to be associated with whatever it is they have declared to be 'the best', and thus bask in its reflected glory. Vranak

Nevertheless, it is a very human trait. I was just going through a bunch of our articles about various bridges (trying to answer this question over at the Miscellaneous desk), and I swear, if you go by our articles, at least half the bridges in the world are the longest bridge in the world. —Steve Summit (talk) 21:10, 1 April 2007 (UTC)

Oh my goodness yes! If there's one thing that seperates man from the animals, it's his extraordinary vanity. Vranak

How do you prove it? I suggest with a series of logically sound deductions based on intuitive and universally agreed upon axioms. I leave it to you to fill in the details. --TeaDrinker 21:51, 1 April 2007 (UTC)

If you were, you couldn't possibly prove it - there are too many people in the world who you'll never be able to compare yourself to. Suppose some Tibetan goat herder were more intelligent than you? How would you ever get to know that? But the very fact that you couldn't figure that out for yourself means that you're probably nowhere near as smart as you think...sorry. SteveBaker 04:24, 2 April 2007 (UTC)

What makes things soft?

The other day I was sitting around wondering what makes certain fabrics subjectively softer than others, and this led me to the article soft matter, which doesn't really explain what makes things soft. There are actually many different types of softness, most of which can be considered the opposite of some type of hardness. I've accumulated a list of such properties and their scientific names in the article hard matter. I think the sort of softness I'm thinking about is the opposite of roughness, though the article roughness only talks about a technical definition of surface roughness which is not what I mean. Texture seems like it's a disambiguation page that wants to be turned into a real article, and touch and tactile are not much help, either.

In particular, I'm wondering what kinds of structures differentiate soft vs. rough or prickly fabrics, skin, etc. Are the effects produced at the molecular level, or due to larger-scale structures (and if so, at what scale)? What role is there to play for interlopers like moisture and oils? -- Beland 23:00, 31 March 2007 (UTC)

Cloth "smoothness" is measured by the thread density. It is measured in Deniers (See Denier (measure)) Raul654 23:04, 31 March 2007 (UTC)

I think you have to look at the micro-scale. Cloth is a bunch of teeny-tiny strands - twisted together into threads - woven together into cloth. The individual threads are very thin - and quite bendy. So when you press against it with your skin, the tiny strands bend and squash to get out of your way. If you took something like a scouring pad - it's made of much thicker strands that are individually much stiffer - so they oppose your skin to a greater degree when you press on it. Those small regions of high pressure prick your nerve endings...not so soft! So I think it's fair to say that 'soft' things are made out of the thinner, more flexible strands - and the rougher, coarser materials have stiffer/thicker strands. This works for things like foam polystyrene versus solid lumps of plastic - the little balls in the foam are full of air - their walls deform easily - so foam polystyrene seems "soft" compared to solid lumps of the stuff. SteveBaker 04:21, 2 April 2007 (UTC)