Wikipedia:Reference desk/Archives/Science/2010 September 13

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September 13[edit]

Question about the flare-drop scene in Waterworld...[edit]

In Waterworld, the bad guys own the Exxon Valdez and keep a little white fella down in the petroleum well to check the levels. I realize this is fiction, but bear with me here for two legit science questions: 1) assuming the little white guy down in his skiff is really in a massive tank, adrift in a sea of oil, would he be able to breathe or would the fumes overpower him? 2) when Kevin Costner drops the flare down the vent pipe into the oil, would the oil really ignite in real life? I seem to recall that certain "flammable" substances can't actually be lit with a tossed match... Masked Booby (talk) 01:44, 13 September 2010 (UTC)[reply]

For Q2, our flash point and flammability limit articles may help you. Ring back if you have more questions. Franamax (talk) 02:15, 13 September 2010 (UTC)[reply]
Flares burn quite hot, so it's not like you're tossing a match in there. The movie, on the other hand, has some very questionable "science" in it. For example, where the hell did they find enough water to raise the sea level several miles???--Dr Dima (talk) 02:28, 13 September 2010 (UTC)[reply]
To your original question, you can certainly have a mixture of methane and air that is breathable but may detonate if ignited; see coal mining and firedamp. Regarding crude oil, or whatever the stuff down there was supposed to be, I do not know if you can have fume concentration high enough to detonate when lit but not high enough to croak the fella. I seriously doubt Kevin Costner ever thought of that. --Dr Dima (talk) 03:00, 13 September 2010 (UTC)[reply]
For Q1, depends on the "oil" and time of exposure. If it is crude oil aka petroleum, still depends, but much less so. Crude petroleum is a mixture of volatile and relatively much more stable fractions. A super-heavy crude would produce relatively less airborne fractions. But what if was actually asphalt in the tanker? You might just get a really bad headache. Or sour crude oil, in which case you will die shortly after you stop noticing the rotten egg smell. In general though, if you are thinking of entering a confined space where hydrocarbons are or were recently present, if you aren't using PPE, expect to die. Even if it was just cleaned, the space might have been purged with nitrogen gas and you will still die. Franamax (talk) 03:12, 13 September 2010 (UTC)[reply]
Because of the context of the movie, if a human can mutate to breath water, there is no reason to assume that human could not mutate to easily breath oil/gas fumes. -- kainaw 03:17, 13 September 2010 (UTC)[reply]
No fair. You obviously have the "extra scenes" DVD! :) Franamax (talk) 04:31, 13 September 2010 (UTC) [reply]
No, that's absolutely impossible, because adding such a mutation would have made it a better movie. Also, breathing oil/gas fumes is not a good way to oxidize food. Wnt (talk) 19:36, 13 September 2010 (UTC)[reply]
Oil is a reducing agent, that's why it burns! Does the oil have free access to oxygen when it burns? If it does, then it could burst into flames. But then, wind might blow away the easily flammable light hydrocarbons and gases present above the crude oil. The heavy black stuff would have a much harder time burning. I would think the hydrogen sulfide and other toxic byproducts found in oil would poison the "white fella" quickly.
Even gasoline does not ignite easily in a bottle! --Chemicalinterest (talk) 20:37, 13 September 2010 (UTC)[reply]

Parabens in Shampoos[edit]

Which shampoo brands have Paraben and which shampoo brands don't have Paraben? 174.114.236.41 (talk) 04:13, 13 September 2010 (UTC)[reply]

What country do you purchase your shampoo in? Often, regulations dictate that such be stated on the product label. Mine has propylpareben and methylparaben. Are you looking for a comprehensive list for one specific country? Franamax (talk) 04:35, 13 September 2010 (UTC)[reply]
This website http://www.cosmeticsdatabase.com/ should help. If they don't have your shampoo on file, register, then you can enter the ingredients yourself and they will analyze it. Ariel. (talk) 18:02, 13 September 2010 (UTC)[reply]
I live in Canada. Can you tell the shampoo brands which have Paraben? 174.114.236.41 (talk) 01:03, 14 September 2010 (UTC)[reply]
I can't. But try the link, they rank shampoos based on a variety of chemicals. Ariel. (talk) 02:43, 14 September 2010 (UTC)[reply]

What is the name of this "cognitive bias"?[edit]

Hello. Currently, I'm conducting a survey. Now I want to analyze it. In that survey I asked for events that rarely happen. So a large proportion of respondents were never confronted to that event. Now I want to compare the group that experienced such an event with the group that did not in order to test if the uninformed group is biased by not experiencing the event. But what is the name for that bias? It is a bit related to the hindsight bias and the misinformation bias, but I'm asking for a bias that has its origin in the fact that a respondent did not experience something I am asking for. 130.149.229.189 (talk) 07:56, 13 September 2010 (UTC)[reply]

Sounds like the problem of induction. 81.131.10.36 (talk) 08:10, 13 September 2010 (UTC)[reply]
I'm not sure you're asking the right question at the moment. Bias is due to a form of poor thinking. If some members' of your cohort with no experience of the event but are willing to give definite point of view never-the-less, then that strikes me as argumentum ad ignorantiam. It might also be dependant on whether the even was an act of nature or and an act against nature (eg earthquake/murder), in which case systemic bias might come into it due to culture. What exactly is the survey; it's too vague. Also, can I take it you meant misinformation effect.--Aspro (talk) 09:02, 13 September 2010 (UTC)[reply]
Earthquake would be a good example for the kind of event I'm asking for. 130.149.229.189 (talk) 09:06, 13 September 2010 (UTC)[reply]
What are you actually asking them? Someguy1221 (talk) 09:18, 13 September 2010 (UTC)[reply]
I'm asking how much an earthquake affected their firm's performance. 130.149.229.189 (talk) 09:27, 13 September 2010 (UTC)[reply]
Technically speaking, what you're talking about is not a bias. lack of experience or lack of knowledge can lead people to certain kinds of biases, but is not considered a bias in itself. The two most common kinds of biases you'll see stemming from information deficits are attribution errors and statistical assessment errors (i.e., errors based or stereotypes or thin Schema, and errors based on exaggerated or diminished assessments of likelihood). --Ludwigs2 09:22, 13 September 2010 (UTC)[reply]
None of these errors/biases really met the "bias" I'm searching for. 130.149.229.189 (talk) 13:31, 13 September 2010 (UTC)[reply]
Are you looking for Ignorance? And I see a few at List of cognitive biases that could apply given what you've said about your survey so far. Can you say more? WikiDao (talk) 14:33, 13 September 2010 (UTC)[reply]
I think you would be better off considering the naïve group to be just that – naïve! They form the 'ground state' that can act as the datum from which other biases can be measured. One can use the result to measure deviation away from the original state but one can't then determine a new value for the original state from the result that is any different from its original value. It is just not logical. If you want to refine the original state more precisely then you need to go about it differently. So I still think your asking the wrong question. --Aspro (talk) 15:03, 13 September 2010 (UTC)[reply]
Confirmation bias?Smallman12q (talk) 01:23, 18 September 2010 (UTC)[reply]

Has there ever been a human culture that did something *besides* smiling to convey what we mean by smiling?[edit]

Cynopithecus niger "when pleased by being caressed"... "Hey guys, what's shaking?"

For example, frowned when we would smile? Or did human facial expressions become standardized before recorded history? Masked Booby (talk) 12:37, 13 September 2010 (UTC)[reply]

No. According to the work of Paul Ekman and others, the facial expressions are universal. That is, they are biological in origins, not cultural. Though earlier anthropologists did believe that they were a cultural thing. If you look up facial expressions of e.g. chimpanzees, their expressions are mostly intuitively understandable to us. So it seems unlikely that early humans had facial expressions that were markedly different from ours. EverGreg (talk) 13:01, 13 September 2010 (UTC)[reply]
Though, as our smile article makes clear, different cultures do have different customs regarding smiling, such as prevalence and frequency. But the smile still means a smile. --Mr.98 (talk) 13:27, 13 September 2010 (UTC)[reply]
And what do we "mean by smiling"? For example, when do we smile to frown? (This experiment is designed to test whether you can spot the difference between a fake smile and a real one.) WikiDao(talk) 15:41, 13 September 2010 (UTC)[reply]
And Darwin would have been interested in this question, too. :) WikiDao(talk) 16:04, 13 September 2010 (UTC)[reply]
If you smile at me, I will understand 'Cause that is something everybody everywhere does in the same language. Dismas|(talk) 19:40, 13 September 2010 (UTC)[reply]

Why does masturbating take longer especially when I'm in a hurry to get somewhere?[edit]

(I'm not trying to be funny here or anything like that; I'm looking for honest answers.)

Just this morning, I was having an okay time masturbating over 30 minutes before I was due to be in class, then when it was less than 30 minutes 'til class started, I tried to rush my masturbation, but it somehow felt more difficult to reach climax. Then just a few minutes before I was to be in class, I was forced to stop and go through the morning routines and leave.

So why is it that masturbating is only done best when I'm not in a hurry to get somewhere? Why does attempting to rush it actually slow it down? --129.130.103.239 (talk) 14:02, 13 September 2010 (UTC)[reply]

See Stress_(biology) for starters. Human sexuality is complicated, adding deadlines probably won't help most people. SemanticMantis (talk) 14:18, 13 September 2010 (UTC)[reply]
I'm not saying this is what is happening to you, but given the nature of your question, some of the delayed ejaculation article may be of interest to you. Vimescarrot (talk) 20:28, 13 September 2010 (UTC)[reply]
What if the OP is female? It would help if the OP could let us know. Smartse (talk) 23:11, 13 September 2010 (UTC)[reply]
Hi, this is the OP, but I'm on a traveling PC, so my IP is different now. No, I'm male. --98.190.13.3 (talk) 05:14, 14 September 2010 (UTC)[reply]
Sexual release usually involves releasing the intellectual mind and sinking into a physical/emotional state. If you are thinking about deadlines it will not be easy to release the intellectual mind, and so it may be difficult to get into the proper state. In those situations, I suggest that you give up the effort, take a cold shower, and go to your appointment - save it for when you can appreciate it properly. --Ludwigs2 05:59, 14 September 2010 (UTC)[reply]

Dead stars turn into diamonds?[edit]

See this article on BBC. It claims when our own sun collapses, its core will turn into diamond? I've never heard of this sort of thing before and it's not in the Stellar evolution article.   Zenwhat (talk) 14:11, 13 September 2010 (UTC)[reply]

Define "diamond". It's quite likely, the so-called "ash" left over after the death of a star that dies in the manner the Sun does is likely to is Carbon, whose nucleus lies at a local stability maximum. According to White dwarf, the core is composed of carbon and oxygen, so when it burns out, it may condense into a pure carbon "nugget". I would imagine that the pressures and temperatures are suffificcent to form diamond, unless a different, heretofore undescribed allotrope of carbon is formed instead. The pressures and temperatures are several orders of magnitude higher than diamonds form at, so it could be that something entirely unexpected could happen. White dwarfs eventually cool into black dwarfs, but the Wikipedia article does not mention its composition. So, to sum up, I suspect that there's nothing to contradict that the remnant of such a stellar death may be diamond. I just haven't found anything to confirm it from Wikipedia articles. --Jayron32 15:14, 13 September 2010 (UTC)[reply]
I think a white dwarf usually consists of electron-degenerate matter. Diamond requires covalent bonding which is not going to happen in a state of electron-degeneracy. So the BBC must be talking about a fairly unusual white dwarf. WikiDao(talk) 15:20, 13 September 2010 (UTC)[reply]
and as Diamond-like carbon (DLC) exists in seven different forms that we know of it could be a right mess.--Aspro (talk) 15:19, 13 September 2010 (UTC)[reply]
See BPM 37093, Presolar grains (maybe), diamond planet, Neptune#Internal_structure. Helium fusion and Carbon burning process are especially important, as it explains where the carbon comes from, and in large stars, where it goes. Yes, most of the salt in our oceans is well-burnt diamond. Wnt (talk) 19:33, 13 September 2010 (UTC)[reply]
at ay rate, it would be a bit difficult to cut, and at that size would be considered fairly ostentatious as casual jewelry. --Ludwigs2 19:51, 13 September 2010 (UTC)[reply]
But you could make a heck of a drill!
Well in an extinct carbon star you could get an atmosphere of gaseous carbon, over a crust or graphite, over diamond, deeper you would get a metallic form as more of the electron shells overlapped, with the majority of the interior being electron degenerate. Graeme Bartlett (talk) 10:29, 14 September 2010 (UTC)[reply]

Explode[edit]

I saw a video of someone overcharging a bettery and it exploded. Flames and everything. They said it was "the words most dangerious battery" but I didn't catch the name. Why would it explode? What's inside them to catch fire? GreenBlade2003 (talk) —Preceding undated comment added 15:12, 13 September 2010 (UTC).[reply]

Sounds like a lithium battery. overcharging-lipo-batteries--Aspro (talk) 15:22, 13 September 2010 (UTC)[reply]
(edit conflict)There are lots of battery types which can explode under certain circumstances, everything from lead acid car batteries to lithium ion batteries. If you type the phrase "exploding batteries" into the Wikipedia search function, we don't have an article directly, but you DO get links to articles which discuss various types of batteries that do explode. --Jayron32 15:23, 13 September 2010 (UTC)[reply]
Nice article in Chemical and Engineering News about what happens when it all goes wrong Hazardous failures of lithium-ion batteries are uncommon, yet researchers strive to minimize dangers. Our article on Lithium-ion polymer battery badly needs this information. The cathodes are prone to releasing oxygen! Here is the Youtube vid World's Most Dangerous Battery!--Aspro (talk) 15:53, 13 September 2010 (UTC)[reply]
Little lithium cells in watches contain lithium metal. It gets hot and sizzles when in water. I used to think of making booby traps with large lithium batteries--have them drop on aluminium foil or something. --Chemicalinterest (talk) 20:32, 13 September 2010 (UTC)[reply]

Words[edit]

I was watching Star Trek and an episode featured them all loosing the ability to communicate because the replicators were making weird coffee. Anyway, basically in their heads the words were being mixed up. So "pizza" to them was "computer" etc. They used a special term, "ahpasic" or something. I want to know what this condition naturally occurring is called —Preceding unsigned comment added by TownCarter (talkcontribs) 15:28, 13 September 2010 (UTC)[reply]

Aphasia DuncanHill (talk) 15:32, 13 September 2010 (UTC)[reply]
The episode is titled Babel, from Star Trek: Deep Space Nine. Wikipedia's article is here; Memory Alpha has a more-detailed treatment. TenOfAllTrades(talk) 19:54, 13 September 2010 (UTC)[reply]

Electrical rating[edit]

I was solving a few sums on AC current..it said a source of 250 v and 50 hz is connected to a 20 W, 50 V electric rated bulb! What is this electric rating...and gow is AC voltage dependent on it??Avril6790 (talk) 15:42, 13 September 2010 (UTC)[reply]

The electrical rating is the voltage the manufacturer intends the light bulb to be operated at. When the rated voltage is applied, enough current will flow through the bulb so that the product of voltage and current will be 20 W (dividing 20 W by 50 V gives 0.4 amperes). If 250 V is applied to bulb the current will be much greater and the bulb will burn out, probably in less than a second.
With alternating current (AC), the voltage also alternates. By convention, the abbreviation AC is used even when discussing an alternating voltage. Usually, alternating voltage is stated as the root mean square voltage. For a resistive load like a light bulb, the effect of 50 V DC and 50 V AC will be the same Jc3s5h (talk) 15:55, 13 September 2010 (UTC)[reply]
is this homework?--Aspro (talk) 15:56, 13 September 2010 (UTC)[reply]
It appears to be! Maybe we can hint that the original poster look at the power output of the bulb under the two circumstances... Physchim62 (talk) 16:10, 13 September 2010 (UTC)[reply]
note: we may be attributing the OP with more intelligence basic knowledge than he really has. The full question hasn't been given so there may be an inductor or possible a resistor involved. --Aspro (talk) 16:20, 13 September 2010 (UTC)[reply]

Ball bearings and turntables[edit]

If you put a ball bearing on a turntable, the ball bearing will appear to move outward, but this is a product of actually moving tangentially to the circle it is on. However, when I've tried putting the ball bearing on a little ramp (with an increasing gradient as one moves away from the centre, in line with a radius, and with "sides" to it, to stop the ball coming off the ramp), this still happens: if you increase the rotation speed of the turntable, the ball bearing will reach a new equilibrium position further up the ramp. These two positions are fairly easy to explain, in considering the gravitational force (downwards) the reaction force (perpendicular to the ramp) and hence an overall centripetal force, presumably equal to the centripetal force you'd expect for circular motion. It is the transition period I don't quite understand. How does speeding up the turntable create an apparent centrifugal force? What forces change, and how do these create an acceleration up the ramp? Grandiose (me, talk, contribs) 19:58, 13 September 2010 (UTC)[reply]

I don't really understand your scenario, but I think you have two accelerations to consider: the constant centripetal acceleration of the revolving turntable, and a brief acceleration perpendicular to that as the turntable speeds up. Wnt (talk) 20:06, 13 September 2010 (UTC)[reply]
Is your question: Why does a higher rotation speed cause a greater force? Ariel. (talk) 02:09, 14 September 2010 (UTC)[reply]
My question is how there is a centrifugal force moving the ball from one position of equilibrium to another, once the turntable speeds up. But let's see if I can explain a little further. Think of a ramp like this, only with "lips"on the near and far sides. You then attach it, tall side outward, along the radius of a turntable. Once you turn the table on, the ball finds a position where the velocity and centripetal force fit (where F is the force inward due to the reaction force of the ramp):
However, we then speed up the turntable. It's now got a higher v, so it needs a higher centripetal force. Low and behold, it finds a new equilibrium higher up the ramp (where the component of the reaction force in the inwards direction is greater). My question is this: where does the force that moves the ball centrifugally from the first equilibrium to the second come from. The usual models of centripetal force don't seem to answer this. In the traditional model, a ball on a turntable moves outward because it moves tangentially to the motion; in my case, the lips of the ramp prevent an velocity in this direction. Grandiose (me, talk, contribs) 16:29, 14 September 2010 (UTC)[reply]
The centrifugal force comes from the ramp, but the ramp's force is perpendicular to the ramp at the point where the ball touches it - upward and outward. The ramp will deliver however much force is needed to keep the ball from breaking it. When the turntable spins more quickly, the upward force more than compensates for gravity and the ball moves up, until it reaches a point where the ramp delivers just the right amount. (It then overshoots, but it'll come back to that point until friction stops it) Wnt (talk) 17:35, 14 September 2010 (UTC)[reply]
I'm not sure: perpendicular to the ramp in upward and inward, since the ramp is going up as you go outward. Moreover, this is why I lack any force with a centrifugal component, except this "outward" one on acceleration (except you would have thought the side of ramp balanced that)Grandiose (me, talk, contribs) 18:09, 14 September 2010 (UTC)[reply]
I assume that Wnt meant to say "centripetal" force. There is no "centrifugal" force, of course, except as an illusion to a small observer in the frame of reference of the turntable who is not aware of the rotation. No "force" causes the ball to move outwards. The ball just obeys Newton's law and continues at constant speed in a straight line until a sufficiently large force (from the friction and normal reaction) causes it to follow the rotation of the turntable. In the transition period, friction is causing an increase in speed, but normal reaction is not sufficient to keep it moving in a perfect circle. Dbfirs 20:34, 14 September 2010 (UTC)[reply]
I think you're missing a bit here, Dbfirs. That is, of course, what would happen if you just put a ball on a turntable. However, during the transition period, the "lips" of the ramp are perpendicular to the acceleration. A newly increased force (presumably friction) in a direction perpendicular to the radius is present, but I would have thought that the sides of the ramp (the "lips") would push back with an equal and opposite force. Grandiose (me, talk, contribs) 16:56, 15 September 2010 (UTC)[reply]
I'm not sure what you think I'm missing, but there is no centrifugal force, just a ball obeying Newton's laws and moving under the action of the forces of friction and the normal reaction. Dbfirs 21:18, 15 September 2010 (UTC)[reply]

Medical question (not a request for medical advice)[edit]

What's the name of the muscle directly above the latissimus dorsi? The UtahraptorMy mistakes; I mean, er, contributions 20:51, 13 September 2010 (UTC)[reply]

If by "above" you mean "farther from the ground", there are several possibilities; but perhaps you are referring to the trapezius. (Compare the bright red portions in the illustrations in the boxes at top right in the articles for the two muscles. By going to the image pages for the lower of the two illustrations, you can even read the labels.) If by "above" you mean "overlying", I believe the answer is basically that, except for a small portion of the lower trapezius, there are no muscles overlying the latissimus dorsi. Deor (talk) 21:41, 13 September 2010 (UTC)[reply]
Rhomboid muscles or Trapezius muscle? these pages have very good navigation templates at the bottom - use those to find related muscles. --Ludwigs2 21:38, 13 September 2010 (UTC)[reply]
Sorry, Ludwigs; instead of giving me an edit conflict the software apparently decided to slip my response above yours. Deor (talk) 21:43, 13 September 2010 (UTC)[reply]

Why must we not eat or drink anything prior to a blood test?[edit]

All my life, when ordered to take a blood test for a physical exam, I've been ordered not to drink or eat anything after dinner the night before. The blood test article doesn't explain the importance of this. I'd like to know why this restriction is in place, and how it would be negatively effected if someone broke the fast. Masked Booby (talk) 21:30, 13 September 2010 (UTC)[reply]

Blood tests need to be normalized to expected values. In other words, they need to compare your blood test to what it should be to know if anything is wrong with you. In order to do this reliably, the doctors need to minimize the number of variables to account for. The less things which are going on in your blood the better, because the more stuff going on the harder it is to know why it is going on. So, if you have an elevated level of some hormone, is it because a) you ate something or b) something is wrong causing it to be elevated. By having you fast, the doctors have eliminated an entire set of variables which can confuse the results and thus make it possible for them to find problems which could be masked or confused by something you ate or drank. --Jayron32 21:43, 13 September 2010 (UTC)[reply]
(e/c) This is to prevent factors from the digested food from entering the blood stream and queering the results. For instance (obvious example) drinking a soda or two prior to a blood test could induce elevated levels of sugar into the blood, which may signify to the physician (falsely) that you have a condition like diabetes. After a half a day or so, most everything that the digestive system is going to extract has been extracted, so doctors can get a decent baseline on your blood chemistry without external influences. --Ludwigs2 21:43, 13 September 2010 (UTC)[reply]
(after multiple ECs) Serum glucose and cholesterol measurements are meant to be interpreted in the fasted state. Otherwise, you could have quite a bit of variability depending on whether someone ate a big plate of pancakes and scrambled eggs, or a small bowl of oatmeal. --- Medical geneticist (talk) 21:44, 13 September 2010 (UTC)[reply]
Thank you for your 3 helpful replies! I have a related follow-up question: are these baseline blood test results compared against simple gender averages? Or do they have a spectrum of "normal" results for age groups? As a specific example, would my grandfather and I (both male) be compared to the same set of normal ranges, or does your blood composition meaningfully change as you grow old? Masked Booby (talk) 01:32, 14 September 2010 (UTC)[reply]
There will be a normal range of values for any given laboratory test. Sometimes there are gender differences and age differences that are taken into account, but it will differ between tests. There are some values that do not change over time and others that do. Is there a specific lab test you are wanting more information about? --- Medical geneticist (talk) 13:06, 14 September 2010 (UTC)[reply]
It's also worth noting that most labs with have varying reference ranges that they use and so one lab may use different standards than others. Regards, --—Cyclonenim | Chat  16:32, 14 September 2010 (UTC)[reply]

Usually you are allowed to drink water. Not drinking anything from evening till the next day is not so healthy. Count Iblis (talk) 01:44, 18 September 2010 (UTC)[reply]

Honda[edit]

does honda sell any "green" or LEED certified cars that dont have MDF ? —Preceding unsigned comment added by Tomjohnson357 (talkcontribs) 21:52, 13 September 2010 (UTC)[reply]

We answer science related questions here. It'd be best if you took it to Wikipedia:Reference desk/Miscellaneous instead. The UtahraptorMy mistakes; I mean, er, contributions 22:18, 13 September 2010 (UTC)[reply]

omg its science related —Preceding unsigned comment added by Tomjohnson357 (talkcontribs) 22:53, 13 September 2010 (UTC)[reply]

What is MDF? Medium density fiberboard? It's not really science, but it's OK, it's sometimes hard to figure where to place a question. If you don't get an answer it's because no one knows offhand, and no one was bored (or interested) enough to research it for you. Ariel. (talk) 02:07, 14 September 2010 (UTC)[reply]
This question also exists on the Miscellaneous Reference Desk. Dolphin (t) 02:20, 14 September 2010 (UTC)[reply]

Paper houses[edit]

I need to know if there were ever recorded structures made completely out of paper. Houses, perhaps palaces? I know it may be ridiculous. However, if there are recordings of advanced structures made out of paper, I'd like to know what type of mathematics were involved. Who were the engineers? Which culture is responsible? What purpose did they serve? I've just got this thought in my head, that the art of paper folding has been used for more than building paper cranes! If I understand correctly the little I've read about it so far, not only was origami a form of mathematics, for instance in Japan, Japanese had also used paper extensively in their dwellings. Thank you very much for replying. —Preceding unsigned comment added by 68.8.173.158 (talk) 21:57, 13 September 2010 (UTC)[reply]

According to the article Papier-mâché, paper had been used as part of a composite building material and used in place of more expensive plaster or wood in some construction applications, see the "Europe" section. Not sure if a house has ever been built with paper as its primary structural element, but there's a lead for you... --Jayron32 22:09, 13 September 2010 (UTC)[reply]

this is not "science related " at all —Preceding unsigned comment added by Tomjohnson357 (talkcontribs) 22:55, 13 September 2010 (UTC)[reply]

what is it then?--Aspro (talk) 23:20, 13 September 2010 (UTC)[reply]

There has been a long history of arm-chair-architects dreaming of paper houses. The Japanese understood the material and therefore did not try and make it do things that paper is poorly suited to. In other words they used it as screens but not for anything that needed to support loads. Here is a link to an American paper house: Paper house from Popular Mechanics . The problem is that it is difficult to ensure that they don't get wet. Even exotic epoxy coatings employed to stop water getting in, only ends up creating a moister barrier that stops moister getting out. In the 1960s hippies also experimented with paper geodetic-domes. The paper they used however, was not acid-free paper and so rapidly became brittle. As the paper (cardboard) formed part of the structural monocoque, the building were just not 'domed' but 'doomed' from the start. --Aspro (talk) 23:20, 13 September 2010 (UTC)[reply]

I've read the articles you guys mentioned, thank you very much, even though it was not what I expected. I have a follow up question though. Origami mathematics in history and their uses. Enlighten me please. —Preceding unsigned comment added by 68.8.173.158 (talk) 01:04, 14 September 2010 (UTC)[reply]

The article on Topology, and any other sources on the subject like books and articles, is what you seek. Topology is the study of the manipulation of surfaces in three dimensions, which is all Oragami is; the deformation via folding of a flat surface. --Jayron32 01:41, 14 September 2010 (UTC)[reply]
We also have an article called "Mathematics of paper folding". :) WikiDao(talk) 02:13, 14 September 2010 (UTC)[reply]
...but topology won't help you. From a topological point of view, an origami model is identical to the original unfolded sheet of paper from which it is made. Gandalf61 (talk) 09:09, 14 September 2010 (UTC)[reply]
An after-school club in Westcliff on Sea, England, is made of cardboard. “The shape of the building reflects some of the properties of cardboard, particularly ‘corrugugated’ cardboard and origami.Origami Sightings - Architecture and Design Come to think of it, nearly every high street in England has a newspaper shop as well...;-) --Aspro (talk) 13:26, 14 September 2010 (UTC)[reply]

Why are these bees mating on the ground?[edit]

http://img826.imageshack.us/img826/6032/bee2.jpg http://img230.imageshack.us/img230/5158/bee16.jpg http://img704.imageshack.us/img704/188/bee17.jpg http://img255.imageshack.us/img255/3742/bee15.jpg

This queen bee appears to be in the process of being fertilized by a drone. However, Wikipedia says that this happens in flight. Why have these bees been doing this on the ground for the last hour?

The bees are "swaying" slightly, so I'm sure at least one of them is alive. Theymos (talk) 22:20, 13 September 2010 (UTC)[reply]

Though honey bee mating `happens in flight', it's not clear to me this means they always decouple before hitting the ground. The drone is in the process of dying (see Drone_(bee)), and the queen may be getting ready to shed her wings (hitting the ground hard may help or trigger this). In this light, it seems reasonable to me that they would hit the ground coupled, and it might take an hour or more to get things sorted out. SemanticMantis (talk) 22:35, 13 September 2010 (UTC)[reply]
Are those Bumble bees? That article has a section on Bumble bee reproduction, which has a bit more information if relevant. I'd be interested to hear/see what eventually happens. WikiDao(talk) 00:29, 14 September 2010 (UTC)[reply]
They look like bumblebees to me. This page says they mate in trees or on the ground. --Mr.98 (talk) 12:13, 14 September 2010 (UTC)[reply]

old article[edit]

title "seven reasons a scientist believes in GOD". Appeared in the 1940's (1943 0r4) how can I get a reprint? —Preceding unsigned comment added by 173.216.80.246 (talk) 23:21, 13 September 2010 (UTC)[reply]

The citation is: Cressy Morrison, “Seven Reasons a Scientist Believes in God,” Reader's Digest, January 1948. --Aspro (talk) 23:30, 13 September 2010 (UTC)[reply]
If you Google for "seven reasons a scientist believes in GOD", the very first link takes you to an online copy of the article. Looie496 (talk) 23:33, 13 September 2010 (UTC)[reply]
They, are, incidentally, just standard, hashed-over arguments, basically just variations on the Teleological argument, the Argument from consciousness, and the Ontological argument. The ones about humans being totally cognitively different than animals were not even good arguments in 1948, the arguments relating to evolution and genes reflect that he had not really taken in the really impressive work being done on the modern evolutionary synthesis yet (which is understandable, if he's retired in 1948), and the final philosophical argument requires you to take on board a lot of Aristotelean assumptions to even make any sense of it. It's a historically interesting piece but should not be taken as reflective of current scientific understanding in any way. I'm not sure it could even be taken as indicative of even late 1940s scientific understanding. --Mr.98 (talk) 00:30, 14 September 2010 (UTC)[reply]