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October 17

Chemistry to dissolve human poo?

What does human poo consist of? fats? protein? is it polar or non polar? and more importantly what is the chemistry that will dissolve it? just like alcohol dissolve oil etc. Electron9 (talk) 02:24, 17 October 2012 (UTC)

What is the chemistry? Don't you mean solvent? It's a complex mixture of both polar and non-polar compounds. Plasmic Physics(talk) 02:28, 17 October 2012 (UTC)

This topic is extensively covered in our article on wastewater treatment. Nimur (talk) 02:31, 17 October 2012 (UTC)

Seems to normally be low on fats, so will just dissolve in water with a bit of agitation. However, some people with non-functional gall bladders or using diet products like Orlistat do pass substantial portions of fat, so adding some detergent would cover those cases. StuRat(talk) 02:38, 17 October 2012 (UTC)

A significant amount of poo is cellulose, which isn't soluble in either detergent or water. --Jayron32 02:50, 17 October 2012 (UTC)

Ah yes, and there's always the corn kernels to deal with, along with seeds and perhaps grains of sand, which aren't going to dissolve in anything short of a powerful acid or base. StuRat (talk) 06:30, 17 October 2012 (UTC)

What's the best household- or easily obtainable chemical to dissolve cellulose ..? Electron9 (talk) 03:15, 19 October 2012 (UTC)

Does bleach work ? StuRat (talk) 22:05, 19 October 2012 (UTC)

Bleach is mostly water, so no, it would not dissolve cellulose. Oxidise does not equal dissolve. Plasmic Physics (talk) 02:39, 20 October 2012 (UTC)

It really depends on what the underlying aim is. Biological washing powders are designed to deal with organic dirt by the use of enzymes. In the laboratory solubalizers such as Soluene might be more appropriate. For drains a mechanical resolution is often resorted to. Rich Farmbrough, 17:48, 27 October 2012 (UTC).

Mystery leaf 'streamers'

Maple leaf with 'streamers'

I took the photograph at right this weekend in central Ontario, Canada, about 100 km north of Toronto. It was on a small maple tree, on which a number of leaves had these dark, vertical 'streamers' (about 1 cm long) sticking out of their upper surfaces. Some leaves had just a few, others (like the one pictured) were heavily covered.

Can anyone tell me what these streamers are? KevinHadley (talk) 03:44, 17 October 2012 (UTC)

Maple spindle galls, caused by a mite. http://www.uoguelph.ca/pdc/Factsheets/Diseases/Maple_Galls.htm μηδείς (talk) 04:01, 17 October 2012 (UTC)

That's pretty neat, the mites are able to alter the leaf cells to grow a gall around them. Tiny genetic engineers at work. StuRat (talk) 06:27, 17 October 2012 (UTC)

Not genetic - it's mostly the result of hormonal effects. Roger (talk) 11:11, 17 October 2012 (UTC)

Neat. Thanks! KevinHadley (talk) 13:49, 17 October 2012 (UTC)

• Wikipedia does have a short article on Galls, which may lead the reader to other information as well. --Jayron32 13:53, 17 October 2012 (UTC)

Why Lube oil consumption of Gas Engine increase after major overhauling.

"Why Lube oil consumption of Gas Engine increase after major overhauling — Precedingunsigned comment added by 182.182.122.148 (talk) 06:20, 17 October 2012 (UTC)

Is that a gasoline engine ? And did they mill down the cylinders ? StuRat (talk) 06:26, 17 October 2012 (UTC)

Gas engine or gasoline engine, taking it that it is in any case a spark ignition piston engine: In vintage engines, a temporary increase in oil consumption above normal tended to occur as carbon at the top of the piston formed a seal - the carbon got removed in overhaul and needs to build up again. However in modern engines, especially for bowl-in-piston/squish land piston/EE-type combustion chambers, a noticeable increase (as distinct from a modest increase) in oil consumption is a sign of errors in rebuilding. Posible errors are: cylinders not correctly honed, incorrect oversize piston and/or rings fitted wrt cylinder re-bore, piston rings incorrect or incorectly fitted, problems with valve guides. A possible problem is the oil presure control spring together with tight bearings causing higher oil pressure leading to over lubrication of valve gear. At one time, new engines and overhauled engines were initially filled with "running-in" low-viscosity oil, which also increases consumption, but this should not be done nowadays. Wickwack124.178.143.72 (talk) 08:17, 17 October 2012 (UTC)

also, minor oil consumption can be caused by lack of absolute cleaning before final assembly which can lead to scoring of cylinder walls, particles lodging in ring grooves, etc. It's also possible that initial ring sealing after rebuild will be not quite as perfect as modern factory engine construction, and will improve somewhat after a little break in period, like in the old days. Gzuckier (talk) 04:27, 27 October 2012 (UTC)

New exoplanet temperature

See [1]. That says the surface temperature is around 2200°F, due to it's proximity to the star. However, at that distance it's sure to be tidally locked to it's star (unless the planet is very young). If we also assume it to have no atmosphere or liquid covering it (having been blown off by the solar wind), wouldn't the dark side be far cooler ? StuRat (talk) 09:03, 17 October 2012 (UTC)

I don't see why not, without a thermal vector, there is no way for heat to be distributed except by good old fashioned conduction. I assume that you're aware of Mercury (planet). Plasmic Physics (talk) 10:35, 17 October 2012 (UTC)

StuRat, you beat me to it! I even wonder if outgassing from the magma side would lead to frozen atmosphere accumulating on the dark side, with the occasional cryovolcano of liquid water and room temperature air awaiting such Robinson Crusoes as our imaginations can devise. :) Wnt (talk) 16:54, 17 October 2012 (UTC)

(ec) This article about the newly discovered planet says near the bottom:

And whichever side of the planet faced the star would be broiling hot, with the other side icy cold.

This doesn't actually say that it's tidally locked, but it makes your point about the surface temperature not being high everywhere.Duoduoduo (talk) 17:00, 17 October 2012 (UTC)

Why do you mention Mercury in this context? Do you perhaps hold the common incorrect pre-1965 assumption that Mercury is tidally locked to the Sun, making its supposed dark side cold? Are you aware of Mercury (planet)? 88.112.36.91 (talk) 20:41, 17 October 2012 (UTC)

I was refering to the effect of a combination of a slow sidereal period, and a lack of atmosphere, to produce a large temperate gradient. Plasmic Physics (talk) 22:02, 17 October 2012 (UTC)

The article says that the dark side of Mercury averages just 110 K, with a "reaches 100 K at night" figure. I don't know if it would reach 77 K and allow nitrogen to condense out if it were locked 1:1 with its orbit. (or 90K for liquid oxygen, if it somehow came to exist; come to think of it, liquid methane at 110 K would be plausible, maybe, if it weren't constantly re-boiled and lost?) Clearly for any satisfying scenario with a reservoir of frozen/boilable atmosphere on Bb, a complete tidal lock would be preferred. But at 0.04 AU ... shouldn't it be? Wnt (talk) 22:13, 17 October 2012 (UTC)

I should correct myself: not slow sidereal period, but a ratio close to one, between sidereal rotational period and orbital period. A ration of 1:1 would indicate tidally locked. A ration of 1:1.5 for mercury is enough to produce a gradient. Plasmic Physics (talk) 01:31, 18 October 2012 (UTC)

To clarify, any low ratio would work to have a cold nightside. But very precisely 1:1 is needed in order for a base on the nightside to last for long. :) I don't understand exactly what happens to atmosphere on this sort of planet, but we know from Venus that even a very slow rotation is enough to keep the whole planet unbearably hot. I don't know if there's a scenario for Bb development that would allow all that atmosphere to condense out on a stationary dark side. Wnt (talk) 17:22, 22 October 2012 (UTC)

Who mentioned a base on the nightside? (Not that I disagree) Of course, Venus' even temperature is due to its atmosphere, precluding it according to my second post. Plasmic Physics (talk) 10:09, 26 October 2012 (UTC)

Appearance

• As an aside, I should mention that the artist's rendition from the article and as shown on our Main Page seems wrong to me. If it's hot enough to melt magma, shouldn't at least some of the planet's edge be visibly red? (see Incandescence, which starts at 525 C) Also, the graphic gives me the impression that from close by the planet, its star looks little bigger than the Moon; but it's only 20 times the distance from the Moon to Earth away from the planet, and nearly as big and half as bright as the Sun. Erm, to put that more simply, at 0.04 AU its star should look 25 times wider than the Sun, and I'm just not feeling that from the picture. Wnt (talk) 22:20, 17 October 2012 (UTC)

The surface may not glow bright enough to be visible with the star in the field of view. Also, if it is tidally locked with no atmosphere, then only the part illuminated by the star would be hot (that was the point of Stu's question), and that glow would be drowned out by the starlight. As for the sizes, that's going to depend on how far away the "camera" is from the planet and the star. The star has about half the apparent diameter of the planet. Since the star is actually about 100 times bigger (assuming the planet is about the size of Earth), that suggests the distance from the the camera to the Sun is about 200 times the distance from the camera to the planet. That puts it about 30,000 km away from the planet.

When viewed from the Earth, the Moon and Sun are both about 0.5 degrees in diameter. Alpha Centauri B from 0.04 AU would 11 degrees (just under 25 times wider). There is no way to know what the angular diameter is from an image like that, though - you would need to know what the total field of view was.--Tango (talk) 18:55, 18 October 2012 (UTC)

perverted justice

I've taken the liberty of moving this question to Wikipedia:Reference desk/Humanities#Perverted Justice (moved from Science Refdesk). Trust me, this is a good thing - you'll get better answers. Wnt (talk) 16:49, 17 October 2012 (UTC)

does a nurse need to expel air from a prefilled flu vaccine

when administering a prefilled flu vaccine does the nurse need to expel any air from the syringe —Preceding unsigned comment added by 95.146.101.33 (talk) 10:54, 17 October 2012 (UTC) |}

Two answers: [1] in general, no, because prefilled syringes generally don't contain air. [2] But if a nurse noted air, in general, he would expel it out of an abundance of caution rather than because it presented any real danger. As a rough estimate, it would take at least 20 cc of air injected directly into the bloodstream to cause an air embolism. A flu vaccination is about 0.5 cc: even if the whole syringe were air, it wouldn't be fatal. And it's also not going into the bloodstream, but intradermally or intramuscularly. See The Straight Dope for more discussion of how much air can be fatal. - Nunh-huh 16:19, 17 October 2012 (UTC)

Air injected into a muscle or under the skin is not particularly dangerous -- it might hurt like hell, though. Looie496 (talk) 16:27, 17 October 2012 (UTC)

If you Google this question, you actually can find multiple bulletin boards of nurses discussing a wide variety of practices. It seems that some vaccines recommend you do, and some recommend that you don't, and most don't say anything at all. I'm not sure there's any real consensus on it. But this is just a Google survey; I have no direct knowledge of this topic. --Mr.98 (talk) 22:44, 17 October 2012 (UTC)

I was recently self-injecting Clexane subcutaneously daily for a few weeks, every prefilled syringe had a small amount of air in it, and the instructions specifically stated "Do Not Remove the air before injection". I asked a few nurses and doctors about it, and their conclusion was that "amateurs" would probably expel half the drug trying to get the air out, and that small amount of air sub-cutaneously would do no harm at all.124.191.177.92 (talk) 07:42, 18 October 2012 (UTC)

Depending on the design of the syringe, there is often a dead volume (why is that red?) that is not expelled when the plunger is pushed all the way in. If the syringe is prefilled "to contain" the stated volume of liquid, the dead volume represents an amount of the stated volume that does not get delivered. If there is a small amount of air also, one can push out all the liquid because the air can be what remains in the dead volume. Calibrating "to deliver", one would include extra volume of liquid to compensate for what gets retained in the dead volume. I have no idea if this is how/why medical folks do what they do, but it's what I've seen done in other syringe-transfer work. DMacks (talk) 02:22, 19 October 2012 (UTC)

Human "fuel efficiency"

We tend to think of biking and walking as "green" alternatives to driving, but it seems to be this may not be true in some cases. Walking and biking don't use fossil fuels, but inasmuch as they require greater physical exertion, they could lead to more eating—human fuel, if you will. Since the production, transportation, and preparation of that food is almost never carbon neutral, could a person be making a more environmentally responsible decision by driving in some cases? If we were to graph it, I could see car efficiency increasing on longer trips. And perhaps hybrid or electrical cars could shift the graph a bit. --BDD (talk) 20:58, 17 October 2012 (UTC)

Keep in mind that fossil fuels are non-renewable (at least not for millions of years) and also release net carbon dioxide which was previously safely sequestered underground. Also, you assume that biking and walking cause you to eat more. Hopefully you lose some excess weight, instead. Then there's the improvement on your health and the inefficiency in caring for unhealthy people (with diabetes and such) to consider. There's also the concept that using a car more wears it out, while using the body more (within limits) actually makes it last longer. But, I suppose, if you have a future solar/battery powered car which is fully charged (so wasting any additional sunlight), then using it might not be bad alternative. StuRat (talk) 21:05, 17 October 2012 (UTC)

If you do the measurement of human efficiency, you have to keep in mind that when you walk/bike to work, you are moving a far smaller mass than if you were driving a car. It's about energy per person-mile. I believe my car weighs over ten times what I do, so I only have to be 10% as efficient as the car to break even. Someguy1221 (talk) 22:25, 17 October 2012 (UTC)

BDD is on the ball and has asked a very good question. In Mark's Standard Handbook for Mechanical Engineers, 11th ED, EA Avallone et al eds, 2007 McGraw-Hill, it says on page 9-5 that the [maximum useable, continous over a work day] power output of a typical healthy adult human is about 400 W, and when compared to the amount of food required to sustain this, the thermodynamic efficiency is about 25% - about the same as a typical 4-stroke gasoline engine under optimal speed and load conditions, but nowhere near as good as a modern turbocharged diesel engine (~40 to 45%). It also says that the maximum human mechanical power output (typical fit adult male) is about 1500 W sustainable for only 0.6 seconds. It should be noted that under typical driving conditions, a car gasoline engine is not operating at optimal load, so the real efficincy will be less than 25%. Incidentally, when I was about 16, I took up intensive weight training at the local YMCA. My appetite increased dramatically, and I've had trouble controlling my weight ever since. The fuel efficiency of fit humans is surpisingly good - old books give data for utilizing animals such as horses to power mills, water pumps, etc, the calorific value of the feed required makes them woeful compared to the IC engine, probably because typical work animals (horses, oxen) all eat food full of cellulose, which has calorific value but is difficult to digest. Ratbone 124.178.52.68 (talk) 00:11, 18 October 2012 (UTC)

However, supposing that vigorous cycling makes you eat an extra loaf of bread a day, that apparently equals around one kilogram of extra carbon dioxide.[2]. According to this table you get 328 grammes of CO2 when you drive one mile in a petrol (gasolene) car or 327 in a diesel one. So you get about 3 miles in your car instead of a loaf of bread. (PS I'm not a scientist, so there may be a serious flaw in my thesis).Alansplodge (talk) 18:20, 18 October 2012 (UTC)

But the carbon in that loaf of bread came from the atmosphere through photosynthesis, so you breathing it back into the atmosphere just gets you back where you started - it's just the carbon cycle. The problem with fossil fuels is that the carbon was sequestered underground for millions of years and would have stayed there had we not burned it. That introduces more carbon into the carbon cycle, which is the problem. --Tango (talk) 19:05, 18 October 2012 (UTC)

You're using the wrong metric, though - we're interested in energy per mile, not energy efficiency. The amount of energy required to travel a mile is going to be very different for a car than a person walking. A car travelling at 60mph has to use a lot more energy to overcome air resistance than a person walking at 3mph. As SomeGuy mentioned, a car is a lot heavier than a person. I don't know the numbers, but I expect cars use far more energy than people to travel the same distance, so even if the car was 100% efficient it would still need more fuel. --Tango (talk) 19:05, 18 October 2012 (UTC)

How much fossil CO2 was released in the course of converting 8g of wheat seed in a farm supply store into a loaf of bread in the OP's kitchen 500km from the farm. That's the real question that needs to be answered. Roger (talk) 19:52, 18 October 2012 (UTC)

To answer your's and Tango's points, the first site that I linked to is talking about carbon footprint rather than carbon capture. An 800g loaf couldn't possibly store 1000g of CO2. So the 1kg of CO2 that I quoted includes all the fossil fuel used in the production, processing and retailing of the loaf. Alansplodge (talk) 21:24, 18 October 2012 (UTC)

The bread can supply the carbon, which your body then combines with oxygen from the air, to produce carbon dioxide, which is exhaled. So, it is possible for the mass of CO₂ produced using a loaf of bread to be higher than the mass of the bread itself. Also note that if you consider all the carbon costs of producing that loaf of bread, then you also need to consider all the carbon costs of extracting the raw materials, building and delivering the car, and extracting, refining and delivering the fuel. Those are not insignificant. StuRat (talk) 20:08, 19 October 2012 (UTC)

I think in the spirit of the OP's question it would be best to consider that the car is one of those biodiesel-fueled vehicles that runs on used cooking oil. Renewable fuels are great, but there are still limits on how much carbon we can pull out of the atmosphere with the available arable land.Wnt (talk) 20:13, 18 October 2012 (UTC)

Also, exercise is necessary for most people to be optimally-healthy and if they're going to go exercise at the gym, or running around their city or the countryside or swimming at the pool, they might as well using that effort to transport themselves for utilitarian purposes. 2.97.23.83 (talk) 17:46, 26 October 2012 (UTC)

The "whole question" of carbon footprint of human energy gets enormous. Compare the total carbon footprint of 500 calories of apples produced by a tree in you backyard that you don't bother fertilizing, versus that of 500 calories of beef grown in former Amazon rainforest by slash and burn agriculture. (Just for extremes; for fun, consider 500 calories of beef grown in your backyard by cattle eating naturally growing grass that you don't fertilize, versus apples grown with use of (synthetic) ammonium nitrate and flown in to the US from New Zealand or somewhere. But I think the first guy is right, the major factor of car vs bike is whether you have to haul the extra 2 tons of metal around with you or not. Gzuckier (talk) 04:35, 27 October 2012 (UTC)

Also if I drive 5 miles to buy food to enable me to walk 2 miles it's a loss for everything except my health (possibly). Rich Farmbrough, 18:04, 27 October 2012 (UTC).

October 18

Redstone

Meh, could someone clarify what is redstone here (concerning the Union Soldiers and Sailors Monument)? Looks like some sort of rock, but there is virtually no info on it in the internet and everything is flooded with Minecraft stuff (and no article in Wiki either).Brandmeister^talk 10:57, 18 October 2012 (UTC)

My guess is that only a description is provided by that term rather than an identification. I would guess that what is known is only the color—red. It is some unidentified red stone. Bus stop (talk) 11:06, 18 October 2012 (UTC)

The OED simply has "stone of a red colour" for this word, but apparently it can also mean red ochre, however that seems unlikely in this context.--Shantavira|^{feed me} 12:29, 18 October 2012 (UTC)

The term is non-specific, and can refer to any type of stone. Could be sandstone, shale, mudstone or even granite or limestone. The only thing you can say for sure is that it sorta kinda looks reddish. As nothing of the sort is visible in any pictures of the monument, it probably refers to the cheaper stone that makes up the bulk of the pedestal, and is sheathed with the more attractive and expensive granite and marble. Dominus Vobisdu(talk) 12:56, 18 October 2012 (UTC)

This color photo of the monument shows that the pedestal has a reddish tint to it.    → Michael J Ⓣ Ⓒ Ⓜ 13:36, 18 October 2012 (UTC)

Most likely because it was taken at sundown or sunrise, with a very red sun. Other photos show that the granite is more gray than pink. Dominus Vobisdu (talk) 13:51, 18 October 2012 (UTC)

I expect you will find the most likely answer at http://www.anr.state.vt.us/dec/geo/redstone.htm, which describes a redstone quarry in Vermont. It states,"the rock is a reddish- purple rock called Monkton Quartzite". Looie496 (talk) 15:45, 18 October 2012 (UTC)

The linked article states; "New Hampshire granite, redstone, and marble." There is a village called Redstone, New Hampshire where there are quarries yielding "coarse constructional stones, all biotite or biotite-hornblende, but varying in colour, pinkish ("red") and dark-yellow greenish-grey ("green") varieties being found remarkably near each other at Redstone, on the east side of the Saco valley. The finer varieties take a high polish and are used for monuments..." Alansplodge (talk) 18:06, 18 October 2012 (UTC)

On a separate note, I think in the Infobox it should distinguish between the material the sculpture is made of and the materials the base is made of.Bus stop (talk) 21:33, 18 October 2012 (UTC)

Matching neurotransmitter and feeling

Can we quantify in ml and name neurotransmitters responsible for each feeling? For example, happiness -> 0.03 ml serotonine, and such.83.52.248.109 (talk) 14:26, 18 October 2012 (UTC)

Unfortunately not. The closest we can come to matching neurotransmitters with feelings are probably "dopamine ↔ pleasure", "norepinephrine ↔ vigilance", and "oxytocin ↔ love", but those are all oversimplified. The role of serotonin has been incredibly difficult to understand, but"serotonin ↔ satisfaction" captures some aspects of it; happiness really doesn't.

Also, because neurotransmitters are targeted and channeled in a very precise way, quantifying them in terms of concentrations is not meaningful. It may make sense for hormones, which diffuse through the bloodstream, but not for neurotransmitters, which are released only at specific target sites.Looie496 (talk) 15:09, 18 October 2012 (UTC)

The effect of the neurotransmitter depends also on the sensitivity of the receptor and the reuptake of it. OsmanRF34 (talk) 15:40, 18 October 2012 (UTC)

• You are making the naive materialist mistake of equating a high-level emergent property with a physical substance. Happiness comes about because of the harmonious arrangement of the factors of your life. Are you healthy enough so you are not in a constant state of suffering, including chemical imbalances? Are you free from major worries about food, money, safety, shelter, the well-being of loved ones? Are your priorities in order, so that you are not frustrating your own goals? Do you have pursuits that bring you passion and pleasure? If your life, body and brain are well-organized and properly functioning you will be happy. This includes the proper levels and flux of hormones and neurotransmitters. But they work as lock and key mechanisms. There is nothing inherent in the shape of the neurotransmitter itself that causes happiness--it is whether it fits and stimulates the right keys, and the whole system works together properly to regulate the traffic of your mid that matters. You could genetically engineer the body to replace serotonin entirely with some sort of pseudoserotonin of another chemical makeup entirely. As long as you also replaced the serotonin receptors with pseudoserotonin receptors you'd be perfectly well off. There's nothing inherent in serotonin itself that conveys happiness. μηδείς (talk) 17:32, 19 October 2012 (UTC)

indeed. for instance, from a (tiny) bit of (objective) experience, I'd say the 'pleasure' center of the brain is badly named; it's more of a 'do that again' center; it can be activated without any real emotions or feelings, pleasure or otherwise, on the part of the recipient. Thus, things like tolerance during addiction, where the 'do it again' function becomes very highly activated, but any pleasurable cognitive response is quite absent. Gzuckier (talk) 04:42, 27 October 2012 (UTC)

electrodynamics

Hello, sorry for being so ignorant, but what is the relation between classical electrodynamics and electronics? The thing is, electronics textbooks, at least the ones I've been reading (hobby-wise), they talk about analyzing circuits, the behavior of the different components and stuff, never about current density, displacement currents, electric flux and things, yet the stuff seems very important, the more so as Maxwell's equations play a role in relativity and stuff, or so I've read or heard. Are those things a higher-level abstraction, of sorts? Can Ohm's law be derived from Maxwell's equations?Asmrulz (talk) 18:01, 18 October 2012 (UTC)

Electrical circuit theory (Kirchhoff's laws and so on) is a special case of electrodynamics in which the electric fields are guided by conducting wires separated by insulators. You can derive these laws from the continuous equations of electrodynamics. Ohm's law and electronics are derived from a combination of electrodynamics and quantum theory, because quantum theory is needed to explain the behaviour of atomic lattices in resistors, charge carriers in semiconductors and electrons in vacuum tubes. --Heron (talk) 18:42, 18 October 2012 (UTC)

Yes. If you look at any introductory electronics engineering course, then (hopefully) the lecturer will start from Maxwell's equations and work from there. Have a search around youtube for some lectures on youtube or similar. IRWolfie- (talk) 20:58, 24 October 2012 (UTC)

Coffee making soda go flat

I have on occasion mixed a teaspoon of instant coffee with a can of decaffinated cola. It makes the soda foam violently. I figured it was a mechanical interaction. But mixing coffee that's already been made seems also to make the coffee go flat. Any info on what's going on? μηδείς (talk) 19:28, 18 October 2012 (UTC)

Most probably Alzheimers. Ankh.Morpork 19:30, 18 October 2012 (UTC)

Nucleation, possibly with a side order of Diet Coke and Mentos? Certainly for the teaspoon of instant coffee, less sure for the already made. --Tagishsimon (talk) 19:36, 18 October 2012 (UTC)

I am not quite sure I get Pork's point, although I watched my mother's father die with Alzheimers--terrifying my sisters who were too young to understand his behavior before he became bedridden--not something to joke about. As for nucleation, yes, that's what I meant by "mechanical interaction". But I have noticed that even when the coffee is already well dissolved it still will flatten soda. μηδείς (talk) 20:34, 18 October 2012 (UTC)

Pork is just making a bad joke, I suppose. OsmanRF34 (talk) 00:21, 19 October 2012 (UTC)

Does coffee completely dissolve, or is there some element of particulate suspension? If so, that might account for nucleation. If not, then we seem to be left with weird chemistry. --Tagishsimon (talk) 20:50, 18 October 2012 (UTC)

I'm no scientist. However, I wonder whether this might hold a clue? It seems to suggest that caffeine itself has a surfactant effect in the soda/Mentos reaction, although not a hugely significant one compared to some of the other ingredients (see the slide comparing the performance of the normal and caffeine-free versions). A Google search brought up various relevant articles about coffee and bubbles. So if the amount of caffeine normally present in diet soda has a measurable but small effect when nucleation occurs via Mentos, the caffeine in your coffee powder will certainly provide the surfactant effect, more than replacing the caffeine in your decaffeinated soda, while the powder itself provides nucleation sites. Maybe the quantity is sufficient to cause foaming and flatness even if the nucleation sites aren't so obvious -nucleation is still occurring on the surface of the glass and presumably on any residue or impurities from the coffee solids. - Karenjc 21:10, 18 October 2012 (UTC)

I'll have to repeat the experiment with some well-dissolved and filtered coffee to see if it still flattens it. μηδείς (talk) 17:16, 19 October 2012 (UTC)

I brewed, refiltered, and cooled some coffee. It did flatten the soda to a very minor extent. Of course the coffee I added to the soda was well diluted at that point compared to adding a teaspoon of instant grounds directly to the glass of soda. μηδείς (talk) 17:21, 21 October 2012 (UTC)

Periodic table of baryons

Our articles on baryons are by their nature a bit hard to comprehend... not helping is that we don't have an orderly scheme to present them all in a complete, visual array. List of baryons is a great beginning, but it doesn't give an overall impression of organization. Articles like Eightfold Way (physics) show little pieces of the elephant, but tend to leave a person more confused than ever. Now, nicer images exist - e.g. the pyramid at[3] - but even that is incomplete.

Now it occurs to me that for didactic purposes only (I'm not saying this has any deep physical meaning) we could arrange the bosons by the quark composition, as follows:

Delta                Sigma        Xi      Omega
uuu uud udd ddd | uus uds dds | uss dss | sss  (u,d,s - the [[baryon decuplet]])

                  uuc udc ddc | usc dsc | ssc
                                ucc dcc | scc  (u,d,s,c)
                                        | ccc

                                ucb dcb | scb
                                        | cbb  (u,d,s,b+c)
                                        | ccb

                  uub udb ddb | usb dsb | ssb
                                ubb dbb | sbb  (u,d,s,b)
                                        | bbb

With J=3/2 and J=1/2 states immediately above and below or side by side in a table. (This would ideally be a cute Wikitable format; I just didn't want to code such a thing when I'm just testing the breeze). Question:

• Is this or some other "periodic table of baryons" actually in use, so it could be sourced and presented as a real concept?
• Our list of baryons lists a number of "prime" particles which have the same quark composition and angular momentum as others. Are these misfiled -should they be moved to the section for "baryon resonance particles"?
• Aside from the J=1/2 vs. 3/2 thing, is there a way to organize the resonance particles as part of such a "periodic table", or is there a very large or unknown potential variety of them?

Wnt (talk) 20:07, 18 October 2012 (UTC)

Is it possible to trap a photon in such way that it remains stationary ?

Hello friends, I need some help to understand photons behavior and I would like to understand the experiments of Nobel prize winners, in physics, in 2012. In everything that I could read about photons behavior, I understood that they move in light speed, they are mediator of electromagnetic forces and they don´t have rest mass because they don´t exist in stationary way. So I read this week in brasilian´s magazins that Nobel prize winners in 2012, have conducted some experiments that keep one single photon stationary ba 10 ms, in a chamber that has 25 cm. Can somebody explain a little bit what actually they did and how this affect our knowledge of photons behavior ? — Preceding unsigned comment added byFuturengineer (talk • contribs) 20:53, 18 October 2012 (UTC)

The Nobel Prize commission, on behalf of the Nobel Foundation and the Royal Swedish Academy of the Sciences, publishes a whole web-page explaining this background for the 2012 Nobel Prize in Physics. There is apress release; a"popular science" introduction to the physics; and anadvanced physics brief for scientists familiar with the topic. These resources explain, in various degrees of detail, the background; the novelty of the physics discovered by the laureates, and the implications to the scientific community. We also have articles on the laureates, Serge Haroche and David J. Wineland (and in Portuguese: pt:Serge Harocheand pt:David Wineland). I believe you may be confusing photons and ions. Have you read through these resources? Any questions still unanswered? Nimur (talk) 00:08, 19 October 2012 (UTC)

Thanks Nimur, I didn´t know this site of Nobel Prize organization. I understood the way that they trapped a photon. Photon is not stationary but reflectin in two surfaces very reflective and close each other. So they send a specail athom and see in the other side if ocurred changes in phase from wave in scuh way that they can detect if therwas a photon or not in cavity. Now my question is regarding decoherence. They mentioned that they can solve problems like Schrodinger paradox and define the way that state superposition goes to just a definitive state. I don´t know how they can determine this, but my question is They can use this to observe double slit experiment and define how/when electron changes from wave to particle ? So their experiment will help to solve this strange phenomenon of quantic phisics ? — Preceding unsigned comment added byFuturengineer (talk • contribs) 02:04, 19 October 2012 (UTC)

Understanding the "live" wire in a home

Hi all, I have just removed my ceiling fan, and sticking out of the ceiling I have three disconnected wires, a black high-voltage wire, a white neutral and a green ground. With the fuse back on, I have tested the wires with a non-contact voltage sensor. Even though the hot wire is not connected to anything, the sensor still shows a AC current in it. My question: didn't we learn in high school that circuits have to be complete for current to flow (or at least be connected to ground)? Why is there an AC current in this dead-end? And why is it that even with this voltage (which has to be high enough to light up the sensor) would I not be able to light a light bulb with a single wire — I'd need to connect the other end to neutral? Thanks! — Sam24.128.48.26 (talk) 21:54, 18 October 2012 (UTC)

Voltage is not the same thing as current. Voltage is basically a force that is capable of driving a current if you complete the circuit. Your voltage sensor, if it's the usual thing, doesn't show current. Looie496 (talk) 23:23, 18 October 2012 (UTC)

yeah, but he said noncontact current sensor. I'm guessing that, given his description of the setup, that there can't be a real current, so it can't be one of those loop around the wire current sensors that picks up a magnetic field from a real current, so maybe it's one of those now seldom seen neon bulb indicators, that can indicate a hot wire by the current passing through capacitative coupling to the wire and/or ground, usually via your hand, or one of the similarly acting IC operated capacitative sensors you can get now. which does in fact make it a voltage sensor, like you said, despite his calling it a current sensor, and answers his question. no curent, just voltage.Gzuckier (talk) 04:49, 27 October 2012 (UTC)

A lot of people, and a lot of books, and use the term "electromotive force," so Looie's terminology is commonplace, but it's still a little bit tricky: voltage is not a force in the same sense that a stretched spring exerts a force. Voltage is in fact a measurement of potential energy per unit charge. Nimur (talk) 23:27, 18 October 2012 (UTC)

Ok, but if there is no current in the wire than what, at it's most basic level, is causing the sensor to register something. Surly the sensor is measuring a rising and collapsing electromagnetic force, right? I assume a guassmeter would also show an EMF, right? But doesn't there have to be actual movement of electrons to cause this changing EMF? — Sam 24.128.48.26 (talk) 12:27, 19 October 2012 (UTC)

If you're working on the ceiling fan, and you didn't turn off the electric mains (by switching off a circuit-breaker, or disconnecting a fuse at the fuse-box), then you should not be working on that ceiling fan. The electricity in a household wire can be fatal. Leaving aside all other discussion about the fascinating physics associated with electricity, do not work on the wire if you aren't sure it's disconnected from the mains. Call an electrician if you aren't trained in proper procedure. In fact, the danger may arise from the same root-cause as the answer to the question: you may be completing the circuit from high-voltage to ground. If the easiest path for current to flow is through you, and not through the return wire,you can be electrocuted. For the sake of completeness, there are other reasons why your meter might show a signal, but if you aren't certain, why take the risk? Nimur (talk) 23:48, 18 October 2012 (UTC)

Thanks. I guess I figured when I said "with the fuse back on" (though I should have said circuit breaker) it was clear that I had switched the circuit breaker while I was in contact with the wires, and that my usage of the non-contact voltage tester was to be double-certain. The disconnected wires are now nine feet above the ground, so it was safe the turn the circuit breaker back on. — Sam 24.128.48.26 (talk) 12:27, 19 October 2012 (UTC)

Turn off the mains electricity for the whole house. I was working on a ceiling lighting circuit earlier this year, and gave myself a painful electric shock. I thought I had isolated the lighting circuit at the circuit breaker - but clearly there was still a significant potential difference between me and the wire I touched! AlexTiefling (talk) 09:58, 19 October 2012 (UTC)

How did you verify that the power was off? You need to measure the neutral <-> ground voltage (to check for miswiring or ground loops) as well as the hot <-> neutral voltage, and should probably check the hot <-> ground voltage for completeness. If any of these shows an appreciable voltage, there's a malfunction somewhere, and you should probably call an electrician. --Carnildo (talk) 00:24, 20 October 2012 (UTC)

That's just the thing - I didn't double-check that it was off. I just threw the circuit-breaker, checked that the light wouldn't come on, and went to work. Once I'd received the shock, I did indeed call the electrician. AlexTiefling (talk) 07:15, 20 October 2012 (UTC)

My rule of thumb; once you've turned off the presumable circuit breaker, before you grab the wire, ground it to make sure. better a fat spark and trip the breaker for a wrongly labeled circuit that blow yourself across the room, at a minimum. Gzuckier (talk) 04:52, 27 October 2012 (UTC)

With AC, there will be a very small AC current flow in a dead-end live wire due to capacitance. The wire is one end of an air-gap capacitor, with the other end being whatever grounded object happens to be nearest. The capacitor charges and discharges on each cycle of the AC voltage. The capacitance is very small, so the current that flows is small. The capacitance of a dead end wire is sometimes called self-capacitance, and modeled as if it did not depend on any ground being nearby (ground is assumed to be at infinity). In real situations, there will always be a ground closer than infinity. Self-capacitance is simpler to calculate, because the geometry of the grounded conductor is ignored.--Srleffler (talk) 17:42, 19 October 2012 (UTC)

• I asked a related question before [4] - the bottom line is that atest light can work either by conducting a hopefully regulated amount of current from the live wire through the user, or can conduct the alternating current from the live wire back to itself (delayed by half a cycle) by using capacitance. Wnt (talk) 17:35, 22 October 2012 (UTC)

which brings up the largely ignored second half of the OP's question; while there isn't enough current via capacitance to light an incandescent bulb, there can indeed be enough to light a little NE2 neon bulb if you can still find one, or sometimes an actual fluorescent tube, dimly. Gzuckier (talk) 04:56, 27 October 2012 (UTC)

Radio station reception range

About how far away could I expect to reliably receive KOKC (AM) from its transmitter location well enough to listen to University of Oklahomafootball games? KOKC is a clear-channel station with technical data found here. With regards to my hometown of Salina, Kansas would I be more likely to receive the game clearly on KOKC or KGSO? I can't seem to find any stations that actually air the OU football games over their online streams, for some reason, so over the air seems to be the only way I can tune in via radio. Thanks,Ks0stm ^{(T•C•G•E)} 22:27, 18 October 2012 (UTC)

Clear channel is an amazing thing. I've picked up WSM (AM) west of the Mississippi, as far as Albuquerque, at night-time, using no special equipment other than my Toyota's AM/FM radio. It seems a no-brainer to pick up a 50 kilowatt AM station that's a mere 250 miles distant over flat ground. Nimur (talk) 23:07, 18 October 2012 (UTC)

AM reception is very erratic, because it depends on the state of the ionosphere. Sometimes you can pick up a strong station a thousand miles away; sometimes it is noisy at fifty miles. Quite often a distant station will come through clearly for a little while and then fade out as the layers in the ionosphere shift. Looie496 (talk) 23:17, 18 October 2012 (UTC)

True, but 50 kilowatts is a lot of power; undesirable effects due to skywave multipathing, bad weather, and all that, often fall well under the noise-floor. If you look at the links on our KOKC article, one includes a map of air-checks with reliable reception ranging across most of the central United States. Nimur (talk) 23:21, 18 October 2012 (UTC)

I have to say, though, that map looks really old, and over the last 10 years or so (as long as I can reliably remember) I have noticed that AM stations seem to be becoming harder and harder to receive, even relatively locally. I don't know whether this is due to power line interference or what. I used to have practically no problem receiving KLIO in Salina (back when it was KFDI-AM), but over the years reception has gotten worse to the point where my car radio won't even pick it up reliably. Ks0stm ^{(T•C•G•E)} 00:33, 19 October 2012 (UTC)

Well, the laws of physics haven't changed much; and the ionosphere, though it changes daily, has beenclosely monitored using many distinct metrics bythe scientists who worry about such things. The most probable effect is that some of the AM stations you've been tuning to have reduced their transmit power as the economics of broadcast radio have changed. (Electricity isn't free, and advertising dollars on AM radio are drying up). However, KOKC and WSM, and other relics of the AM era, are currently broadcasting in the clear at fifty kilowatts, day and night, so for any specified sky conditions, you should be receiving approximately the same signal strength today as you would in 1948. KLIO, on the other hand, is authorized to broadcast only at 1 kilowatt. Nimur (talk) 00:42, 19 October 2012 (UTC)

What has changed over the years is the design of radios, particularly car radios. Up until the 1960's, radios of any quality, and car radios, were vacuum-tube based. Tube design provides high cross-modulation performance. What that is about is this: Any radio has to a cerain extent the undesirable property of cross-mixing radio signals and noise whith that of the signal/station you have tuned it to. In AM reception, the effect varies from just hearing another station in the background, to what radio people call "monkey chatter" (think of multiple Donald Ducks all taking at once) to something like white noise ie hiss. In the 1960's tube designs were replaced by bipolar transistor designs, and in car radios the tuning was based on permeability tuning - sliding magnetic cores. Bipolar transistors are not as good cross-modulation wise as tubes, but the problem was minimised to a certain extent in car radios by multiple permeability tuning circuits that reduced adjacent channel signal strength before it got to the transistors. However, in the last 10 to 15 years car radios are synthesisor based - tuned by microcircuits and not permeability tuning. This is low cost, but cross-modulation performance is very poor. In a nutshell, radios you buy today are not as good in AM noise performance as radios you used to buy.

What has also changed is the widespread use of computers, TV sets, compact flourescent lights, microwave ovens etc, that incorporate switch-mode power conversion. These devices feed back more radio frequency noise into the power wiring that older products did. An individual computer etc may not produce much interference (except close to it), but all the devices in a street each causing noise, adds up to a blanket of noise that makes AM reception harder.

Ratbone 120.145.50.173 (talk) 07:48, 19 October 2012 (UTC)

Maybe more buildings and structures in the way? During the day, you mainly receive ground waves, because the D layer of the ionosphere absorbs much of the signal. Conductivity of the surface also has an effect, so a lowering of the water table could perhaps play a role. If you noticed worse reception at night, maybe regulations are the reason. see here. Ssscienccce (talk) 21:51, 26 October 2012 (UTC)

Sugar, oil, starch in plants

Are those different forms that nature found to store energy in plants? Are they equivalent replacements? And can you divide plants according to their capacity of storing sugar, oil or starch? Or can different plants in the same division implement different solutions? OsmanRF34 (talk) 23:47, 18 October 2012 (UTC)

Good question, and a difficult one. For starters, see Starch#Energy_store_of_plants. Basically, starch is necessary for long-term energy storage, but only after sugars are made first. As far as I know, oils are not used to store energy in plants, but I welcome information to the contrary. I think oils are mainly secondary metabolites, that can aid in defense, signaling, etc. SemanticMantis (talk) 19:28, 19 October 2012 (UTC)

If they aren't, then where does vegetable oil come from?!? Lipid#Energy_storage states "Triglycerides, stored in adipose tissue, are a major form of energy storage both in animals and plants". I don't know how it can be plainer than that. --Jayron32 19:34, 19 October 2012 (UTC)

Ah, of course, thanks. I guess I was thinking more of the various volatile/aromatic oils. SemanticMantis (talk) 21:06, 19 October 2012 (UTC)

Oils do also serve other purposes in both plants and animals, besides energy storage, like providing flexibility to exposed surfaces without evaporating too quickly, as a solvent for oil-soluble substances, etc. StuRat (talk) 19:54, 19 October 2012 (UTC)

October 19

What facts and examples should I use in a debate with a Relativity Denier?

I have been asked to 'defend Science' at a Creationist event, and the guy I'll be debating is against 'Einsteinian Relativity', or as he characterizes it, the idea that there is no universal reference frame. To summarize his position bluntly, "There IS a universal reference frame, and it is God."

I'm hardly qualified if this were any sort of scientific event, but it isn't, and looking at the guy's credentials, neither is he. What sorts of examples, facts, and topics should I review and study up on to back up... well, modern scientific thought on this?

Note: if you have any biblical quotations, those will be helpful as well, as creationists infrequently listen to logic and rationality.

Here's the 'Moderator's Introduction':

Whenever a Relativist says: “space is curved,” this merely begs the question: “Curved in relation to what?” If the Relativist says: “time slows down,” we respond: “Slows down in relation to what?” If he says that he has a “preferred frame of reference” we ask “what frame, and in reference to what?” Every proposition a Relativist utters assumes there is an absolute against which he can measure his proposition. To put it another way, the whole theory of Relativity, ironically, is based on the assumption that something is at rest. Even if he says “the speed of light is my absolute,” we respond: “the speed of light in relation to what?” And if he is someday so bold as to assume he has a “what,” we are still going to ask him “what in relation to what?” and thus require him to prove his “what” over against any other possible “whats.” If he says, “the universe is at rest” then he is once again on our side, since he has already admitted there is no difference between a rotating Earth in a fixed universe as opposed to a fixed Earth in a rotating universe. God has sprung a trap for modern man, and Relativity is its name.

I assume most of us on this site find this ridiculous, but why, specifically? I'm not asking anyone to spell out a transcript of what to say, just point me in good directions while I prepare; wiki articles to read, experiments to read up on, biblical passages to memorize, etc. — Preceding unsigned comment added by 146.63.171.193 (talk) 01:05, 19 October 2012 (UTC)

If the real issue is Creationism, it's a huge tactical error to get sucked into a debate about a different issue. It's an even bigger error if you don't actually understand that issue. Trying to win a debate by memorizing arguments you don't understand is what the bad guys do. Don't be one of the bad guys.Looie496 (talk) 01:52, 19 October 2012 (UTC)

Yes, congratulations! You have been sucked in to be the sucker they use to make whatever they want look stupid. They'll be doing their preparation too -they'll be checking the sorts of arguments put up elsewhere by people such as yourself, and will come equiped with counter arguments that worked - i.e., not counter arguments that are correct, necessarily, but arguments that experience has shown will amuse/satisfy their captive audience, and confound you.

There are a multitude of practical applications of Einstein's general theory, and especially his special theory of relativity. For example, nuclear power is one that everybody knows. E = mc² is the core engineering equation for nuclear power. One that is less appreciated is the picture tube in TV sets (before they went to flat screens based on plasma and LCD technolgies). These worked by emitting electrons from a hot cathode at the back of the tube. Electrostatic forces are used to accelerate these electrons in a focused beam toward the screen; when they hit the screen, dissipation of their kinetic energy causes the screen to glow. Magnetics are used to make this electron beam sweep back and forth and up and down. It happens that these electrons travel at a significant fraction of the speed of light - so due to Einstein's theory, their mass increases. So the magnetic force required to sweep the beam is greater than would be expected. Picture tube engineers must understand and apply the theory in order to make tubes that work correctly. The widespread use of picture tubes and X-Ray tubes that work just as predicted by the factory engineers is a proof of Einstein's theory.

However, I'm with Looie496. What any of this has to do with creationist ideas (essentially, God created in spurt of effort every mineral and every plant and animal without using evolution) is a mystery to me.

Wickwack 124.182.48.155 (talk) 02:15, 19 October 2012 (UTC)

The introduction itself makes it obvious the person who is moderating this event does not understand relativity. You can't really debate with people who have made up their minds on a subject they haven't bothered to learn. What they really need is a physics lesson, not a debate.Someguy1221 (talk) 01:56, 19 October 2012 (UTC)

"You can't reason someone out of a position they didn't reason themselves into." -Phil Plait 67.163.109.173(talk) 02:07, 19 October 2012 (UTC)

According to Wikiquote, Jonathan Swift said that. -- BenRG (talk) 16:41, 19 October 2012 (UTC)

Doesn't mean Phil Plait didn't say it too. —Tamfang (talk) 07:35, 20 October 2012 (UTC)

Simply ask your fellow debater to express their idea in mathematical form, and use these equations to make a prediction about a physically-observable effect. For example, if they contend that there is a universal reference frame, they should be able to express the governing equations of electrodynamics in a way that predicts a variation from the documented results of the Michelson-Morley experiment. If the person can not express their ideas mathematically, or is unable to see how they relate to the question of a physically-observable fact, then inform them that they are unqualified to make assertions about the topic, and move on to discussing other interesting issues with them - issues that do not relate to empiricism and mathematical physics. Many interesting conversations are to be had with non-physicists, and sometimes even with people who hold beliefs that are contrary to empircal observations. Or, you can find a new group of people to discuss physics with, who are able to back up their assertions about the physical universe with logically-consistent observable consequences. In its present form, it seems that the debate is centered entirely on the name-label "relativity," and notactually on the mechanics of the theory that holds that name. The debate can not make progress in that form; it is little more than name-dropping and appeal to authority. One side appeals to God, and the opposing side appeals to "facts that were established by very smart and infallible physicists," but neither side actually brings any substance to the discussion. Nimur (talk) 02:21, 19 October 2012 (UTC)

Never make the mistake of thinking that because someone believes in something stupid, that they themselves are stupid. You get highly intelligent creationists! Prepare to be out argued! Wickwack 124.182.48.155 (talk) 02:25, 19 October 2012 (UTC)

You're talking at cross purposes. Moral relativity and the theory of relativity are two completely different things. You can't prove the first and final answers about the purpose of the universe or whether there is a God based on some scientific observations. And he can't predict the shift in spectral lines of a distant star based on the brightness of a "standard candle" supernova. Wnt (talk) 02:31, 19 October 2012 (UTC)

Take this opportunity to teach audience about relativity. At the end, do mention you are aware that you cannot win a debate because science is based on knowledge, and there is limit to knowledge but there is no limit to ignorance. manya (talk) 03:16, 19 October 2012 (UTC)

1)God isn't an inertial reference frame, so its ludicrous to argue God is one. 2)They need a physical model based on a classical space that accurately explains observed facts such as the Michelson-Morley experiment, relativistic Doppler relation, time dilation, length contraction and E = mc². 3)Given a classical space, with Galilean transformations (if they know what that is) explain why if the universal vacuum speed of photons and other bosons is not invariant (the same speed in every reference frame), why it appears to be invariant. 4)If they can do the above, such a model wouldn't entail the abstract nonEuclidean geometries and maths of Minkowski space and the relativity of simultaneity. And in case any of you guys are wondering about my complete insanity, with a couple of very simple ideas, I've figured out such a model too... -Modocc (talk) 03:34, 19 October 2012 (UTC)

God and relativity are not necessarily incompatible (just like God and evolution, see theistic evolution). From the perspective of fine-tuned Universe God is the creator of physical laws and as such you can't extend scientific laws and theories, including relativity, on Him. Catholic doctrine in particular says that God exists beyond time (and of course is not affected by ageing), while relativity needs both time and space (the spacetime).Brandmeister^talk 09:53, 19 October 2012 (UTC)

That doesn't look like an impartial moderator. Would you get into a boxing ring knowing the ref would punch you too? And it looks like they'd have trouble with Newtonian relativity, never mind Einstein's Special and General theories. There are no Bible quotes that can back you up here - not because relativity is anti-Biblical, but because it deals with questions that the text was not written to answer. But if they're not Young Earth Creationists, you could do a lot worse than to argue that the six days of Creation in Genesis reflect an Iron-age approximation of the stages through which the universe went in order to produce living things. (I don't believe that myself - I think it's just the prelude to a series of moral just-so-stories - but it's not nearly as bad an argument as theirs are shaping up to be.) If they are young-earthers, then you're stuffed, because a lot of the astronomical evidence relies on accepting that there have been more than 6000 years.

I'd take the fight to them. Rather than defend your positions, try to tease out theirs. What is the speed of light in a vacuum, in their physics? If there is an absolute frame of reference in the physical world, what and where is it? If they mention God at this point, direct them to John 1:18 - "No-one has ever seen God". Attempts to express God as a physical frame of reference are bound to leave them in contradiction of scripture. But yes - Wnt is right. They have done the spectacularly ignorant thing that many such people have done, and conflated physical relativity with moral relativity.

Newton was a devout (if non-conformist) Christian, and saw the exploration of physics as an investigation of the methods and glory of God. He was certainly a moral absolutist, and yet he developed a theory of relativity that stood for 200 years, and is still the best everyday approximation of universal law. If they can't grasp the difference, they fail before you even start. AlexTiefling (talk) 09:48, 19 October 2012 (UTC)

While Alex and others have said a lot of sense, I think they are missing an important part of how you are most likely stuffed before you begin, at worst, and at best, what you really have to grapple with. This "event" - it's not just a debate between 2 opposing people with a (biased) moderator. It is relatively easy to win and argument with one or two people who have some misconceptions thru ignorance. But this "event" is I assume, to be before an audience. An audience of creationists. Creationists of all sorts maybe - ones who can think, ones who can't think. Ones who will simply not tune in to what you are saying, but will tune in whenever their side appears to land a blow. In short, its entertainment, and you are part of that entertainment, under their control. You have to win the audience, not the debator(s).

If you start talking about science or math, more than half the audience will simply tune out. If you ask them to explain with their physics what is the speed of light, they'll most likely replay with something that has nothing to do with it, but calculated to make you stop and think. Then they've won in the eyes of the audience. Wickwack 120.145.50.173 (talk) 10:35, 19 October 2012 (UTC)

I'm not against creationism, but that that is just a silly argument. Try this: since God created the universe, which includes everything (space and time), who's to say that there exists a concept such as time outside of the universe? You run into a philosophical dilema when you propose that God created the universe around Himself, that is if you agree that He was before the creation of the universe. It would be foolish to assume that God's computer runs on a Windows opperating system, just because our one does. For all we know, He could have Linux. Plasmic Physics (talk) 11:18, 19 October 2012 (UTC)

I agree with the folks who are telling you "don't even enter this debate". There is no upside for you (unless perhaps you are doing this for a bet ?). It won't even give you any useful experience of debating. If you were asked to give your opponent $100 and then convince him and his friends to give some of it back to you, would you agree ? Just tell the "moderator" that his introduction is so biased and his arguments are so absurd that you are withdrawing from the debate. Gandalf61 (talk) 11:04, 19 October 2012 (UTC)

Spot on. Of course when you do that, they may tell each other that the scientist (you) chickened out because, deep down, he/you knew your argument was never going to be any good. But that doesn't matter, if you were set up to lose anyway. Folda 120.145.5.61 (talk) 11:17, 19 October 2012 (UTC)

I agree, and this really is advanced stuff. If you really explain things you will probably lose your audience. There are things that you need to be able to understand and demonstrate mathematically. Take a observer and two people moving away in opposite directions at 25% of the speed of light, 50% of the speed of light and 100% of the speed of light - what would be observed from each point. Once understanding the theory you need to show them evidence for its correctness (Michelson–Morley experiment, clocks in plains, gravitational lenses, GPS timing), and show why it precludes there being any absolute frame of reference - which is something beyond me (after all couldn't there be some view from an extra small dimension which sees all other points as close, as some quantum theories state).

After all that they will turn round and say "well if it contradicts God being omniscient then its wrong because the bible says so". -- Q Chris (talk) 11:17, 19 October 2012 (UTC)

(Fairly ad hominem, but ask him what he thinks about Einstein. Every Relativity denier I've ever interacted with was also a fairly vicious anti-Semite and unable to hide it when talking about him, for whatever reason.) If it were me, I would just explain that Einstein's theory is a theory of gravity, it has nothing to do with morality or theology. (Einstein himself got tired of people making such connections himself and lamented that he hadn't called it the theory of invariants instead, since it is not the relativity — which is just an extension of Galilean relativity — that makes it interesting, it is the conjunction of the relativity with an invariant speed of light that comes up with funny effects.)

As a theory of gravity it has completely conformed with predictions and experiments; GPS wouldn't work if relativistic corrections weren't applied. It has absolutely no impact on whether there is or isn't a God. If you want to interpret the Big Bang as an act of Creation you are welcome to, but science isn't going to shut its ears up if it sees something that doesn't conform with your perceptions of it. This is really a textbook case of a false dilemma between science and religion — there is nothing in the equations of GR that make it even slightly against a notion of God.

I don't think you need to prove to them that GR is real or that the math is real or whatever. Kick that one down the hall to the scientists and the technologists — if GR didn't work, then various technologies based on it wouldn't work, and they clearly do work. The issue is one of the guy being confused about what he thinks the science says, and it really doesn't say that. You don't have to try and argue that God didn't exist or didn't kick off the Big Bang or something. GR has nothing to say on that point. I don't see why opposing GR is a plank of Creationism, frankly.

The moderator's intro contains many obvious errors — an actual physicist will tell you, straight up, what the reference frames are. They don't say "time slows down absolutely," they say, "time in frame A slows down relative to frame B." There's nothing inconsistent there. Personally I'd just put up the Lorentz transformation equation and the GR field equation and ask them which of the entities named is God or has any relevance to him.--Mr.98 (talk) 11:32, 19 October 2012 (UTC)

I've met a (probable) Jew who denied Relativity, though he may have been merely making a joke. Louis Epstein (I may misremember the name) was a fanatical monarchist, or at least posed as one for laughs (and was usually amusing, rather than trollish). I once concocted a scenario involving a king and his heir whose deaths are separated by a spacelike interval – that is, near enough in time and far enough in space that neither one lives long enough to learn that the other has died – and therefore whether the heir was ever king depends on frame of reference. Louis replied (paraphrase) "Impossible; the kingship transfers instantly, in every frame of reference, and therefore Relativity is wrong." —Tamfang (talk) 07:35, 20 October 2012 (UTC)

Here's an alternative approach: Attack their theology. The idea that 'God has sprung a trap for modern man' is fundamentally anti-biblical, and anti-Christian. The idea that the God of truth and love would inspire the creation of a mostly secular theory in order to deceive his suffering creation is insane. In mainstream Christian theology, God already came into the world as a human being in order to suffer and die, so that people could be freed from pain and sin. God's love is portrayed as being all-encompassing. So why on earth would he ever seek to lay a trap for us? Psalm 19 draws explicit parallels between the consistency of the physical law and the perfection of the moral law. Relativity is a consistent physical law, and experiments (including concerning the motions of the Sun, as mentioned in poetic language in the Psalm) back it up. And yet these people would rather claim that the universe isnot consistent, and that God has deliberately deceived us, in order to trap us into sin and damnation.

So my 'official' advice to you - as someone with undergraduate degrees covering theology, scripture study, special relativity and formal logic - is to refuse to debate with them because they doubt the consistency and truthfulness of their own God. AlexTiefling (talk) 11:40, 19 October 2012 (UTC)

Wow, that is an awesome answer. Here is a quote "Any fool can start an argument." Plasmic Physics (talk) 11:51, 19 October 2012 (UTC)

Agreeing with Alex, you could also point out that I John 1:5 says explicitly that "God is Light", not some Universal Reference Frame. Why do they say different to their own Scripture? --TammyMoet (talk) 12:24, 19 October 2012 (UTC)

Carefull! Although the creationist said "God has sprung a trap for modern man", if you try the argument "why would a loving God set a trap for (all) mankind, they'll come back and say "God set a trap for the modern relativity scientist man, not for us faithfull creationists." Floda120.145.5.61 (talk) 12:55, 19 October 2012 (UTC)

That sort of circular logic isn't worth engaging with. My advice is definitely to stay away, for the reasons everyone has outlined.AlexTiefling (talk) 13:03, 19 October 2012 (UTC)

• I think the key to the argument is that, while God is universal, He cannot be the "reference frame" as the term is used in physics. To be a reference frame, you'd be using it to measure the motion of another object against. How does one measure the motion of anything against God? If your debate opponents can't answer that, you've won. --Jayron32 12:42, 19 October 2012 (UTC)

Straight to the OP's question: "Nuke them from high orbit. That's the only way to be sure."

And just as it happens, it'll demonstrate relativity in a way they can't deny... ;) — Precedingunsigned comment added by One.Ouch.Zero (talk •contribs) 13:02, 19 October 2012 (UTC)

See here and in case of objections, you refer to this page. Count Iblis (talk) 16:38, 19 October 2012 (UTC)

I agree with everybody here: don't engage in this silly "debate". Instead, take this opportunity to learn some science. I'll comment on the moderator's points, not because I think the OP should bring them up in a debate, but for the OP's own enlightenment.

1. Space is curved in the sense that if you transport a gyroscope around a closed loop, parallel to its own axis, its axis will point in a different direction than when it started. A completely uniform universe can be curved, in the same sense that a 2D bug on the surface of a balloon thinks its world is both completely uniform and positively curved.

2. Time slows down for a moving object relative to the guy observing it. That is the only sense in which time slows down; it doesn't slow down with respect to any global reference frame.

3. There is no preferred reference frame in general relativity. In special relativity, non-accelerating frames are privileged. You can tell which frames are accelerating: if you put an elevator there and get in, do you get smashed against one of the walls?

4. The speed of light is not absolute. In special relativity, it's the same in every inertial reference frame. There isn't a well-defined speed of light in an accelerating reference frame, because it depends on which direction you measure it.

5. The universe is not at rest. There is no difference between saying that the universe is rotating while Earth is not, or Earth is rotating while the universe isn't; in general relativity, every reference frame is equal. --140.180.242.9 (talk) 17:17, 19 October 2012 (UTC)

I couldn't read through all the answers, but take my advice in this sort of questions: discussing with people who analyze plain scientific phenomena from, and only from, a biblical perspective is not worth your time. No matter how good your evidence, they can always reply that God created that evidence, that he wanted to confuse us, that we are too small to understand his greatness and so on. Once you introduce a concept like God into a discussion everything goes, if God allows. OsmanRF34 (talk) 19:56, 19 October 2012 (UTC)

• I got it! Ask him whether there is any speed you can go, that God isn't with you. (You can then follow up by saying that, like your relationship with God, the laws of physics don't change depending on what speed you are going, and relativity is a way of working that math that agrees with this.)Wnt (talk) 20:04, 19 October 2012 (UTC)

That sounds like the start of a good answer. The basic flaw in the creationist's premise is what a "reference frame" is supposed to be. If God is everywhere, but invisible (just like the blackness of space, or the classic notion of the "aether"), how does that figure into anything? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:50, 19 October 2012 (UTC)

Uh huh. Right, as if. That idea, just like this "debate" and just like all of religion, makes as much sense as colorless green ideas sleep furiously. --140.180.242.9 (talk) —Preceding undated comment added 20:41, 19 October 2012 (UTC)

I'd take a non-contradiction approach: the relativity principle merely says that we cannot know what the absolute reference frame is, if there is one. Consider up and down: they are not the same for me in America as for my friend in India; if God has an up and down, how are we to know where they are? Newton – no atheist, as has been mentioned – showed that it doesn't matter where we put our spatial coordinate axes (so long as they don't rotate); Einstein showed that spacetime has a Minkowskian geometry in which it doesn't matter (within limits) where we put our temporal axis. God may have a preferred coordinate system for spacetime but has not seen fit to show us its axes. —Tamfang (talk) 07:35, 20 October 2012 (UTC)

If there is a preferred coordinate system, we can know what it is though. I've mentioned this before, but its worth repeating, I predict that the absolute reference frame is precisely the inertial reference frame with the universe's fastest identical clock rates. We know that both gravity and acceleration slows decay rates, but what we have not observed yet is what set of particles has the fastest decays. Therefore, perhaps observations will show that particle decay rates are generally slower than for those whose objects happen to be at rest with respect to the Cosmic microwave background. This idea alone is, of course, not enough to show that space and time are classical, for this takes more assumptions and thought. For instance, with an invariant simultaneity and the fact that every frequency is a proportionality between events, say the revolutions of two planets, A and B, then a frequency of A can be defined in terms of B, as in A revolutions per every B revolution, then, by the assumption of invariant simultaneity, their proportionality, or the defined frequency, will be the same in every reference frame. Getting the maths to work out to my satisfaction has been difficult, but once I figured out what is required, these actually have turned out to be simple. I am not sure yet when I will publish, because there are substantial details still needed to make my model complete that I've not yet figured out, and I have this more important invention to work on that needs completion too. -Modocc(talk) 15:51, 20 October 2012 (UTC)

So far as I know, the fastest decays should be in your own frame of reference. I have to agree that the CMB and the overall distribution of galactic velocities suggests an absolute rest frame at any given point in space, and I suspect there's some physics that takes advantage of it, e.g. FTL which can never travel backward in time relative to the rest frame for a specific locality. But I anticipate that the absolute rest frame varies from place to place (just like that of the CMB) per Hubble's law, and any such physics is as yet undiscovered. Wnt (talk) 17:42, 21 October 2012 (UTC)

With the Twin Paradox, twins can have different reference frames, but one of these will be observed to age faster than the other (or others), thus different inertial frames are not the same in this regard. Thus its a matter of observation to determine which reference frames of the universe have the fastest rates of aging when these are compared. You seem to have implied that the CMB varies from place to place, but AFAIK, observers in other galaxies are measuring the same CMB. -Modocc (talk) 18:14, 21 October 2012 (UTC)

You can expect them to use the same tactics as when "debating" about evolution. I've read a few reports from such debates, and tips for those that want to enter them. Your google skills are probably as good as mine, but I'll point you to some examples from the NCSE web site:[5] [6][7] [8]. In addition to what others have said, look out for the "Gish gallop" where the other side trots out a large number of one-liner questions which each would take several minutes to answer well.Sjö (talk) 08:38, 21 October 2012 (UTC)

as fate would have it, i've been mulling this over with my Fine Mind lately. My conclusions, after a whole half hour or so, were that we as humans are stuck with a single, subjective, point of view; and God would presumably be capable of an objective, universal point of view. That's pretty hard for a human to imagine. But, the development of science is towards mimicing as best as possible, this universal, objective POV; thus, relativity; which would sort of pull the old switcheroo on your opponent. There is a universal reference frame, and it would presumably be God's, but either way, that's what Einstein is saying. Gzuckier (talk) 05:05, 27 October 2012 (UTC)

Etymology of M. manavi

Hello. When Oldfield Thomas described Miniopterus manavi in 1906, he did not explain the etymology of manavi. Does anyone have any idea what it could refer to? Thanks in advance. Leptictidium (mt) 08:46, 19 October 2012 (UTC)

An idea: from the latin "Mano"(manare, manavi, etc)-- to drip or flow [9]... so possibly it is a bat that drools a lot? Perhaps there is something "flowing" about its wings? SemanticMantis (talk) 14:06, 19 October 2012 (UTC)

Extremely unlikely: manavi would mean "I have dripped", so it would be a bizarre form of the word to use in that context.--ColinFine (talk) 21:09, 23 October 2012 (UTC)

Names like that are often taken from a person. I don't know who "Manav" would be, though. Looie496 (talk) 14:16, 19 October 2012 (UTC)

Yep, I thought of that too. Problem is that there appears to be no trace of anyone named "Manav" or "Manavo" who is related to Madagascar or bats.Leptictidium (mt) 14:50, 19 October 2012 (UTC)

According to this page (bottom entry), there's a Malagasy word manavy that denotes a small bat.Manavi is likely a Latinate representation of that. Deor (talk) 18:07, 19 October 2012 (UTC)

Thanks, I think that's it! Leptictidium (mt) 10:40, 20 October 2012 (UTC)

About Karl Emil Lischke

Hi all,
Apologies for creating a fuddle I should be following up myself. Looking at refs at de:Karl Emil Lischke, nl:Karl Emil Lischke, and fr:Karl Emil Lischke, I am at a loss about to migrate those to the en:wp article.
--Shirt58 (talk) 12:19, 19 October 2012 (UTC)

Edit: Still can't find refs in English.--Shirt58 (talk) 13:21, 19 October 2012 (UTC)

You don't have to have English refs if none are easily available. I suggest you use the French refs on the grounds that they are (possibly) the easiest for native English speakers to understand. There is discussion about this theme atthe Village Pump. Richard Avery (talk) 14:02, 19 October 2012 (UTC)

There are no French refs; the French article's only source is the German article. Isn't one of the refs on the German article in English? --140.180.242.9 (talk) 16:50, 19 October 2012 (UTC)

Coastal armoring in Connecticut

Does anyone know which areas of Connecticut's beaches have the most Coastal armoring structures? Does anyone know what Connecticut coastlines were never modified through coastal armoring or Beach Nourishment?149.152.23.9 (talk) 19:58, 19 October 2012 (UTC)

Not a direct answer, but note that Long Island provides some protection from ocean waves to most of the Connecticut coast, thus reducing the need for coastal armoring. StuRat (talk) 20:01, 19 October 2012 (UTC)

Also not a direct answer, but if beach erosion is something that interest you generally, you could do worse than to look into the work of Orrin H. Pilkey, who works in the field and is something of an expert on the topic. --Jayron32 04:24, 21 October 2012 (UTC)

Terri Schiavo

Was Terri Schiavo alive after she became brain-dead? Based on her date of death in that Wikipedia article, I'm tempted to say Yes, but I'd like to hear about the views of others on this.

To quote the article: "Terri Schiavo died at a Pinellas Park hospice on March 31, 2005." By definition, and not withstanding Schroedinger's cat, if she was not dead until March 31, then she was alive before that. She was not brain dead, but in a persistent vegetative state prior to March 31. (I don't know what happened to my signature. It was here two days ago when I wrote this. Bielle (talk) 20:32, 21 October 2012 (UTC))

Thank you for clarifying. However, I have a question--in regards to brain dead individuals, would it be fair and accurate to biologically classify them as dead if the rest of their bodies are still working due to artificial aid? Futurist110 (talk) 21:27, 19 October 2012 (UTC)

If they have functioning vital biological processes, such as heart and lungs, they have to be considered alive. ←Baseball Bugs^{What's up, Doc?} carrots→ 21:42, 19 October 2012 (UTC)

Biologists generally don't concern themselves about issues that come down to the meaning of a word. Legally, though, a person who is brain dead is considered dead. Looie496 (talk) 21:44, 19 October 2012 (UTC)

Not everywhere, according to Legal_death#Brain_death it is not like that in every US state. I suppose there are several different legal definitions of death around the world. OsmanRF34 (talk) 22:41, 19 October 2012 (UTC)

I was not asking about legal definitions, but thank you for your info. For the record, though, I don't think that people withglobal ischemia would be legally classified as dead despite having no brain activity (electrical activity in the brain) for up to several minutes. The global ischemia article itself talks about electrical activity temporarily stopping, so your previous statement about electrical activity continuing in patients with global ischemia appears to be inaccurate. Therefore, I think that the legal definition of brain dead would be more along the lines of "you're dead if all electrical activity in your brain permanently stops with no chance of ever getting it back."Futurist110 (talk) 00:02, 20 October 2012 (UTC)

I think you misunderstood the article. As I understand it, if electrical activity in the brain completely ceases, there is never any recovery. I didn't see any statement to the contrary in that article. Looie496 (talk) 16:50, 20 October 2012 (UTC)

No, I don't think I did, since the article said "In 1974, Hossmann and Zimmerman demonstrated that ischemia induced in mammalian brains for up to an hour can be at least partially recovered" and that "[t]he interruption of blood flow for twenty seconds results in the stopping of electrical activity." An hour is obviously way longer than 20 seconds. Also, I've heard that the book What Happens When We Die by Sam Parnia supports the statement that I just made. Futurist110 (talk) 22:07, 20 October 2012 (UTC)

If their stomach cells are alive and functioning, then their stomach is alive. If their heart's cells are alive and functioning, then their heart is alive. Whether the whole person is alive if some parts are dead is an uninteresting semantic question that, as Looie said, biologists have no reason to consider. --140.180.242.9 (talk) 22:06, 19 October 2012 (UTC)

I'm interested in this question due to the whole brain life vs. life part of the abortion debate. Futurist110 (talk) 00:02, 20 October 2012 (UTC)

From a scientific standpoint, life began about four billion years ago and forms a continuous chain of "aliveness" since then. There's no meaningful point at which you can say a person "started to live", because from a biological standpoint, sperm and egg cells are just as alive as an embryo. --Carnildo (talk) 00:46, 20 October 2012 (UTC)

You can't try to seek scientific answers to semantic and moral issues, because there simply aren't any. Science can describe how somatic cells split through meiosis to form gametes, how the gametes combine to form zygotes, how the zygotes split and develop, and what an embryo/fetus looks like at a given stage of pregnancy. Personally, I see absolutely no purpose, aside from the purely semantic, in trying to define when an embryo becomes "alive", or "human". You might as well replace "alive" with "phillip" and "human" with "trodinos". The statement that "an embryo becomes phillip after 3 months and trodinos after 6" has as much moral significance as the statement "an embryo becomes alive after 3 months and human after 6": in other words, absolutely none, because we made up the definitions of the words in the first place. --140.180.242.9 (talk) 06:50, 20 October 2012 (UTC)

We've been asked when she was "alive" and/or "dead"; discussion of the ethics of her treatment might better be pursued with a more focused question at the Humanities desk

• What do you mean, "was she alive"? She was judicially murdered[10][11] by the Florida Supreme Court with the complicity of the US Supreme Court at the request of her adulterous "husband". Had her parents gained custody, she might have been rehabilitated. But the court decided that she be starved to death rather than let that happen. μηδείς (talk) 01:44, 20 October 2012 (UTC)
  • --Jayron32 01:51, 20 October 2012 (UTC)

The left wing village voice and the right wing wash times good enough for you? A court ordered starvation counts as judicial murder in any human's book.μηδείς (talk) 02:00, 20 October 2012 (UTC)

Regardless, it is entirely off-topic commentary here on RD/S and unrelated to the thread-topic either. DMacks (talk) 02:12, 20 October 2012 (UTC)

If the OP wants an independent objective scientific answer, he simply won't get one, or at least not a better one than the picture will provide. No testimony independent of witnesses solicited by the husband who gave hearsay evidence she wanted to die was ever procured. If the OP is only asking for the substance of the legal judgments they can be found and linked to. μηδείς (talk) 03:03, 20 October 2012 (UTC)

I fail to see how the witnesses, the legal judgements, or the picture help with the OP's question. As far as I know, the fact that she was alive but in a vegetative state was in no way questioned by anybody in any court. The picture shows that she was not in an advanced state of decomposition, but that's about it. --140.180.242.9 (talk) 06:50, 20 October 2012 (UTC)

Murder is the unlawful taking of human life. There is no such thing as "judicial murder". You might hate how the case was handled, but it was done with "due process of law". ←Baseball Bugs ^{What's up, Doc?}carrots→ 04:39, 20 October 2012 (UTC)

This from the guy who says you can't murder a horse. μηδείς (talk) 18:41, 20 October 2012 (UTC)

Murder is the unjust taking of human life. (Bugs and I have both omitted some other key features.) The concept existed before legislation. An unjust killing that follows the forms of law may never be punished as murder, but still is what it is. (But I am not informed enough to give an opinion on the case in question – and do not care to become so.) —Tamfang (talk) 07:49, 20 October 2012 (UTC)

Ironically, you have just affirmed my statement. Note EO's take on "murder"[12] "secret" or "unlawful" killing; and "just"[13] as "legal" and also "right in the eyes of God", the latter being a matter of dispute, which is why we have laws to define these things. ←Baseball Bugs ^{What's up, Doc?}carrots→ 16:39, 20 October 2012 (UTC)

Laws, at best, express a pre-existing moral consensus, in which case they are redundant to the definition of justice; at worst, they express the interests of an insider class, in which case they are irrelevant to an honest definition of justice. Thank you for calling my attention to the Roman meaning of ius, but I hope we've outgrown divine law as the foundation of ethics. —Tamfang (talk) 18:16, 20 October 2012 (UTC)

Sorry, I'm hatting this - this sidetrack looks like it killed the main discussion. Wnt (talk) 20:15, 21 October 2012 (UTC)

Feel quite free to continue the discussion then--it's hardly proper to hat what you may see as an unpopular viewpoint, one supported with references and reflected in a law passed by congress and signed by the president. μηδείς (talk) 20:20, 21 October 2012 (UTC)

• • • To take the opinion out of Medeis's long-form answer and return to the OP's question: "Yes, she was alive." And that just happens to be what every preceding answer has said, in greater or fewer words. Bielle (talk) 01:59, 20 October 2012 (UTC)

DNA Question

I apologize if this is a stupid question, but is our identity (what we develop into, etc.) caused by our DNA? For instance, what would happen if technology allowed us to modify/change a human's DNA and replace all of it with a cat's DNA? Futurist110 (talk) 20:59, 19 October 2012 (UTC)

DNA is an important part of the biochemistry of living things, but there are a lot of other things going on too. And if you stop and think about it, magically altering the DNA in your every cell in an instant, aside from being impossible, could be extremely traumatic to your body. But if you catch it early enough, like right when an egg is fertilized, you might be able to do something. That's how genetic manipulation is done currently. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:39, 19 October 2012 (UTC)

Yes, I believe that some techniques for cloning extinct animals rely on removing the DNA from a close extant relative, then placing the extinct animal's DNA in the nucleus. However, with something as different as a cat and human, I suspect some incompatibility in the DNA and organelles in the cell would quickly kill the cell. StuRat (talk) 22:03, 19 October 2012 (UTC)

Is technology capable of eventually modifying these differences between cat and human zygotes as to turn one into the other in an experiment successfully? Futurist110 (talk) 00:03, 20 October 2012 (UTC)

I suppose, but you arrive at a Ship of Theseus situation. You could also replace components on the QE2 and eventually make it into a jet plane, with nothing remaining but the ship's wheel. StuRat (talk) 00:24, 20 October 2012 (UTC)

Also - they start with gametes, not with mature individuals. AlexTiefling (talk) 22:48, 19 October 2012 (UTC)

If our DNA was somehow instantly changed to cat DNA, we would rapidly die, possibly within 24 hours. DNA contains the instructions for making all the body's proteins, and cat proteins are not compatible with human proteins. Looie496 (talk) 21:50, 19 October 2012 (UTC)

"Within 24 hours"? No, it would certainly be within minutes, because DNA is being transcribed and translated into proteins at every instant and in (almost) every cell. There is simply no way that a human body could chemically function with a cat's DNA. As for the OP's question, definitely. Have you ever seen twins, and noticed how similar they were? Exactly how much genes matter and how much the environment matters is an ongoing and heated debate called nature versus nurture. --140.180.242.9 (talk) 22:03, 19 October 2012 (UTC)

Within minutes qualifies as within 24 hours. :) If you could change not just the DNA but also everything else in the body that is required to support a cat's biochemistry, then you might have a fighting chance of surviving. But it would all have to happen in a nanosecond (unless it's a sci-fi movie). ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:36, 20 October 2012 (UTC)

So you're saying that if turn a human into a cat, the cat can survive. Well yeah, we know that; nobody's saying cats can't survive (in fact, they have nine lives). --140.180.242.9 (talk) 06:35, 20 October 2012 (UTC)

Well, I'm postulating that it could survive if a complete and instantaneous biochemical transformation could occur. The problem is, if you do this to an adult, they'll be a cat in the form of a human, and that might have consequences of its own. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:55, 20 October 2012 (UTC)

I'll volunteer for being turned magically into a cat. But I get to decide who I live with Asmrulz (talk) 18:08, 20 October 2012 (UTC)

See Somatic fusion. You can take a human cell and a mouse cell and fuse them without killing them. Of course, this is different from the hypothetical scenario in which you start off all human and replace with all mouse - you'd have to try the experiment to see what would happen. :) (Cloning one species with the cytoplasm of another involves something much like this, but the nuclear proteins are transferred, and I don't know of anyone trying that far of a genetic distance) Wnt (talk) 01:40, 20 October 2012 (UTC)

• The most significant difference between cats and humans is developmental. Once adulthood is reached, body form is set. Tissues that regenerate, like hair, would probably take on a feline appearance. Probably the biggest difference would be metabolic enzymes. One might develop the ability to produce one's own vitamin C, but lose the ability to metabolize a lot of the alkaloids that humans deal with. Having a cat's liver enzymes would significantly change your dietary requirements and tolerances. I doubt there'd be any immediate problems, just cosmetic and dietary. There might be mood changes due to a change of hormonal and neurotransmitter balance. And cats age much more quickly than humans. How you would react to catnip and cats of the opposite sex would be curious. μηδείς (talk) 18:34, 20 October 2012 (UTC)

Would we still have an intelligent human mind if we would have been successfully transformed to cats in adulthood? Yes, right? Also, if a human being's DNA was completely and successfully changed into that of a cat at the zygotic stage, then this human being would develop into a regular cat after the DNA changes, right? Futurist110 (talk) 22:20, 20 October 2012 (UTC)

The brain is a network of neurons that functions using electrical impulses and neurotransmitters under the influence of sense input and hormones. The long term balance of neurotransmitters and hormones might change under the influence of cat genes, but probably no where near radically enough that it would disrupt sentience sapience. But mental health might be affected by mood alteration and changes in impulses. There is no way to know what would happen long term without experimentation. A person whose genes were replaced with cat genes in one fell swoop might simply die of a massive auto-immune reaction. [14]. But they won't turn into a cat. μηδείς (talk) 23:30, 20 October 2012 (UTC)

Cats do have sentience, but not self-awareness. What if a human zygote's DNA was completely changed into a cat's DNA (and doesn't die as a result)--would this human zygote then develop into a cat instead of a human? Futurist110 (talk) 23:59, 20 October 2012 (UTC)

I meant to say sapience, not sentience. Zygotes haven't yet reached anywhere near the stage where there is a difference between cats and humans, so you'd simply have a cat at that point, maybe with human mitochondria, which shouldn't matter. It would be like creating a cat clone using human host cells and cat nuclei. μηδείς (talk) 00:39, 21 October 2012 (UTC)

• I think the answer is really that you have to try it and see what happens to know. I can vaguely picture you do something akin to X-inactivation on a spare animal genome in an engineered individual, then [somehow] get the cell to destroy/discard its first genome while reactivating the second one. It seems like a procedure well in excess of our capabilities... for now. Wnt (talk) 17:36, 21 October 2012 (UTC)

You can do exactly that in bacteria, which was famously done in 2010: Craig Venter#Synthetic Genomics. It cannot yet be done in anything more complicated than a particular bacterial species with a mere ~1mb genome. Someguy1221 (talk) 21:36, 21 October 2012 (UTC)

But there are some very good educated guesses we can make. Genes are mostly either structural genes or regulatory genes. The structural genes code for things like the structure of collagen and so forth that are basically the same in cats and humans. Some enzyme proteins humans have cats won't have, and vice versa. That will mostly end up in changes to dietary needs and tolerances, and changes in balances of hormones and neurotransmitters, but not their function. As far as regulatory genes, those that govern growth and development will largely be out of play once the skeleton is formed, and the body matured. Regenerated tissues like the stomach lining and blood will slowly become more cat like. (Eggs and sperm will become cat's eggs and sperm, so any children if conceivable, should be kittens.) But that will have little effect on the adult animal. The skin and hair will change to cat skin and hair--a striking, but largely cosmetic change. But body layout, the wiring of the brain, the skeleton, the shape of the musculature, the arrangement of the organs--that is all set once development is complete. Functioning at the cellular level is regulated by highly conserved genes, and basically identical among mammals. μηδείς (talk) 20:40, 21 October 2012 (UTC)

Cardiac arrest

Hello,

During a tuition on cardiopulmonary resuscitation, I've been told by the instructor that cardiac arrest was always causing heart fibrillation and pulmonary arrest in adults (no pulmonary arrest in newly born infants), hence requiring chest compressions and assisted ventilation. Why does cardiac arrest prevent breathing in adults and not in newly born infants? Thanks, 188.194.48.183 (talk) 21:06, 19 October 2012 (UTC)

Either you didn't grasp correctly what the instructor said, or you need a new instructor. Cardiac arrest is the cessation of pumping. Fibrillation is the uncoordinated crontraction (twitching) of heart muscle fibres. There's 2 main locations of fibrilation: in the upper return chamber (atrial fibrilation), which in the short term doesn't matter much (my wife has been in AF for months and will probably stay that way) Lots of things can cause cardiac arrest, and one of them is extensive fibrilation in the lower (main pumping to body) chamber. You cannot breath in cardiac arrest because the breathing muscles aren't being supplied with fresh oxygenated blood if the heart is not pumping. A newbon infant suffering cardiac arrest cannot breath for the same reason as an adult. If still connected via the umbilical cord to the placenta, and the placenta is still attached in the womb, the baby can still get oxygen, but without a pumping heart it can't use it. Floda 124.182.4.128 (talk) 01:02, 20 October 2012 (UTC)

I may have made a confusion while listening to him. It's clearer with your explanations. Now, if I come across an unconscious person who is unable to breathe and whose pulse can't be felt, I have to perform a CPR by default; just for curiosity (as I am not supposed to make a diagnostic during basic life support), this person can suffer from cardiac arrest, heart attack or fibrillation, is that right? Is the AED able to determine in which condition is the victim before delivering a shock? 188.194.48.183 (talk) 10:14, 20 October 2012 (UTC)

Your IP address geolocates to Berlin. First aid training varies from country to country and from time to time. I am Australian - first aid training here had the following principles, when I did my Senior Certificate:-

1. Follow "DRABC" - Do in this order: Check Danger (to yourself), Response, Airway, Breathing, Circulation (Pulse & bleeding).

2. For response checking, attempt to wake person up. If person is awake or shows some sort of response to shaking, yelling and the like, there cannot be a serious problem (yet) with breathing or heartbeat.

3. If no response, Check for breathing - feel rib movement, or feel for breath with your face. If person is breathing, there MUST be a pulse.

4. (if not breathing) Check for pulse at neck. Neck pulse is reliable, as a live body will always ensure blood flow to the brain. In severse cases, the body may shut down blood flow to limbs in order to do this. However, if you can detect a pulse at wrist or ankle, well and good.

5. If not breathing but there is a pulse, commence moouth to mouth & check frequently that there is still a pulse.

6. If not breathing and no pulse, commence CPR cycles.

7. Do not do heart massage if there is a pulse - you will make any heart problem worse.

First aid givers, whether Junior or Senior First Aid trained or not, are not required to make any diagnosis beyond the above points. If there is no neck pulse, it matters not a whit whether it is because of fibrillation, loss of blood volume thru bleeding, a heart attack, or wound, blood flow MUST be restarted. So Fisrt Aiders are not required to diagnose fibrillation, however if you do detect fibrillation and you can advise medical personell via phone, well and good. Note that Atrial fibrillation is readily detectable but is NOT life threatening. Low chamber fibrillation will very likely result in cardiac arrest, which if it has already happened, youll have no pulse, requiring CPR. If fibrillation causes cardiac arrest in a conscious patient, they'll faint, so you go thru DRABC again.

Portable automatic defibrillators all sense whether a pulse is occuring - they will not fire if they detect a pulse (more correctly, they detect a QRS Complex http://en.wikipedia.org/wiki/QRS_complex), as nothing heart-wise needs or should be done unless and until there is no pulse. Therefore you can do no harm using an automatic defibrillator (assuming you don't interrupt mounth-to-mouth, where required, too long messing about) when not required - it simply will not fire if it is not needed. Cardiac arrest can occur from all sorts of causes, but the patient can't live without blood flow, so if no neck pulse & you have a defib machine, give them a zap - it might work.

Floda 124.178.131.13 (talk) 12:53, 20 October 2012 (UTC)

I was just looking forward to the details of the AED pulse measurement and how the machine was able to interpret it, but your DRABC explanation is welcome. This DRABC procedure is exactly the same as the one I've been instructed in France. The QRS complex keyword routed me toa manufacturer documentation, which gave me more answers than I could expect! Thank you for your time, 188.194.48.183 (talk) 13:30, 20 October 2012 (UTC)

Crossing the Atlantic, the order is different. The formal American Heart Association recommendation is now CAB (circulation-airway-breathing)--seeCardiopulmonary resuscitation#Methods for details and refs. Their rationale is essentially that even a little circulation immediately with residual air is better than checking for breathing and doing rescue breaths before the first chest compressions. A victim with no pulse is in more immediate danger, so is addressed first (and presumably would wind up needing breaths also, so "look listen feel" is not done). And they suggest that it's easier to teach and get nonprofessionals involved in at least the first step than a more involved process--and both the new process itself and likelihood of "someone doingsomething" are more likely to lead to a successful outcome for many cases. DMacks (talk) 17:50, 20 October 2012 (UTC)

On a somewhat similar note, there were attempts in the UK to persuadeuntrained bystanders to assist heart attack victims using chest compressions only, rather than full CPR. The aim, apparently, being to encourage them to at least do something, rather than doing nothing through nervousness. Of course, trained first aiders would still do more.--Demiurge1000 (talk) 18:58, 20 October 2012 (UTC)

Actually when I last trained in the UK 2010, I was told to only use compressions. This is because of the risk of infection (nobody uses the proprietary barriers apparently), and also because you don't know whether there is a blockage between nose and lungs: blowing it down into the lungs could do more harm. --TammyMoet (talk) 09:25, 21 October 2012 (UTC)

That may be due to the regional variation in training that was mentioned above. However, the correct technique for Mounth-to-Mouth is to pinch the victim's nose off & blow in to mouth. There is a posibility of a blockage in the throat, but that is easily checked for and (mostly) easily cleared. Blockages between the nose and throat thus do not matter at all; blockages lower down than the first tracheal split do not matter much. What does matter is that the patient does get some air movement. Ratbone 121.215.62.205 (talk) 16:12, 21 October 2012 (UTC)

AFAIK professionals in the UK are supposed to use mouth to mouth. They don't teach it for amateurs I think because research shows the prospect puts off a number of people from doing resus at all. --BozMo talk 10:18, 21 October 2012 (UTC)

That is an interesting statement. Can you prove it with a reference? At least in Australia, professionals NEVER use mouth-to-mouth - being professionals (whether abulance crews or hospital staff or doctors) they have on hand, or within fast access, ventilators (mouthpiece & valves connected to rubber bulb). Mouth to mouth is taught to non-professionals because such folk will NOT have a ventilator - for them M-to-M is the only realistic option. Professionals have a high probability of encountering an infectious patient, and they don't want to carry it to the next patient. But the probability of getting anything more than the flu from an unconscious accident victim you encounter is very low. Ratbone121.215.62.205 (talk) 16:04, 21 October 2012 (UTC)

You can trust the Americans to do things different - whether it is electrical standards, govt standards, metric vs traditional measurements, first aid or whatever. Meanwhile Australian fisrt aid teaching has followed European practice and is now DRsABCd - seehttp://www.stjohn.org.au/images/stjohn/information/fact_sheets/DRSABCD%20A4%20poster.pdf). This is really just a slight adjustment to DRABC - s for send for help, d for defribrillate, as the machines are now widely available. Ratbone 120.145.68.9 (talk) 02:28, 21 October 2012 (UTC)

Why do pet parrots enjoy being stroked and cuddled by people?

Question in topic. As far as I know, there are very few other birds that actually like being handled, even when tame. Some birds might allow you to touch them a bit or even pick them up, but will make it clear from their body language that they'd rather you didn't (e.g. canary, myna bird, zebra finch, pigeon, chicken) and will bite you if you keep doing it. Any ideas? --91.125.132.147 (talk) 21:15, 19 October 2012 (UTC)

Many wild parrots engage in social grooming. SemanticMantis (talk) 21:58, 19 October 2012 (UTC)

I grew up on a chicken ranch, and as a child I had my own pet chickens that I raised from eggs. Who says their body language says they don't like being handled or petted? Even as adult chickens, they would come up to me and jump into my hands. Of course I aways bribed them with grain and other things that chickens like to eat. Floda 124.182.4.128 (talk) 01:08, 20 October 2012 (UTC)

Yes, I'm with the IP editor above. Chickens handled from early on can become very comfortable with it and actively seek out handling. And because I've seen such signs, I just did a Google Images search on "beware of the parrot". Very revealing. I've been bitten many times. I would just add the word "some" to the OP's question. HiLo48 (talk) 01:27, 20 October 2012 (UTC)

Animals in general aren't too keen on being handles handled unless they're used to it. Before your time, perhaps, but there was a place calledAfrica USA, I think film director Ivan Tors was connected with it, and they raised many of the animals with what they called "affection training", i.e. handling them from a young age. Even not terribly cuddly critters like tarantulas were affection trained. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:29, 20 October 2012 (UTC)

the local guy who drags various crawly animals to kid's parties, etc. says that he can make pretty much any of the animals he's handled (including hissing cockroaches, tarantulas, etc.) comfortable with handling and more or less recognize that he's neither prey nor predator, except for alligators and crocodiles, which he says will inevitably try to predate anything that moves and are of suitable size, no matter how familiar it may be. Gzuckier (talk) 05:14, 27 October 2012 (UTC)

I agree that animals aren't keen on being handles. I once tied a live snake in a loop and used it as a handle for my suitcase, but, judging from the rattle, he seemed to object. StuRat (talk) 05:49, 20 October 2012 (UTC)

I just knew I should have fixed that typo before you got your hands on it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:50, 20 October 2012 (UTC)

Yes, non-Australians often gain the impression that koalas are cute and cuddly creatures. Nothing could be further from the truth. They LOOK cute, but their natural behaviour involves lots of really ugly noises, fighting among themselves over members of the opposite sex, and ripping human flesh with the quite evil claws they possess. Those available for cuddling in tourist traps are separated pretty early on from their mothers and given the affection training Bugs speaks of above. HiLo48 (talk) 05:57, 20 October 2012 (UTC)

And beware the drop bears. :-) StuRat (talk) 06:53, 20 October 2012 (UTC)

Parrot and parakeet nomenclature?

Another quick parrot question. Or maybe this is a question of language use?

Where exactly is the demarcation line between parrots and parakeets? The term "parakeet" implies a small bird, so something like a macaw might have the long tailed 'body plan' of a parakeet, but I can't imagine anyone ever referring to macaws as anything other than 'parrots'.--91.125.132.147 (talk) 21:19, 19 October 2012 (UTC)

Parakeet indicates that "parakeet" refers to any number of species that are small members of the order of parrots. So, there is no clear biological distinction between the two terms, and usage will vary by region. Insofar as we can make "rules" for common names, we can say that all parakeets are parrots, but not all parrots are parakeets. SemanticMantis (talk) 21:55, 19 October 2012 (UTC)

• What birds outside the rather restricted Loriinae (Budgies, Lories & Fig Parrots) are considered parakeets? μηδείς (talk) 01:39, 20 October 2012 (UTC)

not to be confused with paracletes, which seem to be more likely doves.Gzuckier (talk) 05:08, 27 October 2012 (UTC)

October 20

Tea bag infusion

If you place a tea bag in cold water, will it eventually produce the same concentration of tea as if you place it in boiling water ? If so, how long will it take ? If not, why not ? StuRat (talk) 02:52, 20 October 2012 (UTC)

I have read various sources that for various teas a certain temperature is necessary to release various essential oils. For example:http://empiretea.com/tea_facts.htm This would imply that cold water will not do the trick. That makes sense since you are not trying to dissolve just one pure crystal that is fully soluble at room temperature, but many different substances, some of which may not enter solution below a certain temperature.μηδείς (talk) 02:58, 20 October 2012 (UTC)

That's also why you would want to use hot, but not boiling water when steeping tea and coffee: many of the bitter or unappetizing flavors tend to dissolve at boiling temperature, plus boiling agitates the leaves and breaks them up. this site recommends anywhere from150 °F (66 °C) to 205 °F (96 °C) for the ideal steeping temperature depending on the type of tea. --Jayron32 04:46, 20 October 2012 (UTC)

Wouldn't the temperature be below that for sun tea (not to mention refrigerator tea) ? StuRat (talk) 05:33, 20 October 2012 (UTC)

Jayron, that well-known scientist Douglas Adams says precisely the opposite. He maintains the waterneeds to be boiling and not just hot. -- Jack of Oz ^[Talk] 05:49, 20 October 2012 (UTC)

The cold water infusion is not unusual in Japan. It takes 2 to 6 hours. See [15] and [16], the translation is terrible though. But I prefer to using boiling water. Oda Mari (talk) 08:29, 20 October 2012 (UTC)

DNA is being a little loose with his terminology. The water isn't actually boiling when you make the tea - it has stopped boiling a second or two beforehand. --Tango (talk) 15:31, 20 October 2012 (UTC)

That's not loose terminology. "Boiling water" is an accepted phrase for water at its boiling point, even if it is not currently simmering. The point is that you want the water still at its boiling point when it hits the tea. This is different from green teas and herbal teas, where you generally want the water to have cooled slightly to 95C. 212.183.128.23 (talk) 17:21, 20 October 2012 (UTC)

Eurgh, no. You can't get a decent cup of tea up a mountain because the water needs to be as close to 100C as possible. Herbal teas and coffee need to be brewed at more like 95C, for maximum tastiness, but British black tea needs boiling water. You then pour the 100C water on the tea in a warm vessel, and then it is brewed in about 2 minutes (varies by blend). Any longer, and it gets too tannic. Any lower, and it's weirdly weak because the most delicious compounds don't get released.

Wait, "boiling agitates the leaves"? We're not adding the leaves to water that's still being heated.86.159.77.170 (talk) 12:46, 20 October 2012 (UTC)

• I'd just like to comment that this is one of those questions where everybody has strong beliefs and nobody has any evidence to back them up.Looie496 (talk) 15:42, 20 October 2012 (UTC)

Sure we do. We know that British people trying to make cups of tea at high altitude get disappointing results unless they use special equipment. We know that the flavour profile of tea brewed at 95C is different from the flavour profile of tea brewed at 100C, and that this reflects a difference in the compounds in the tea. We know that different sorts of tea react differently to temperature and length of steeping: British black tea specifically requires boiling water, while green teas and herbal teas require water that has slightly cooled. "Required" here meaning "required in order to produce a product that people generally enjoy drinking". We know that allowing tea to stew (leaving it in the water for more than a few minutes) significantly increases the tannic content, making the tea bitter and astringent. We know that tea left in cool water for a long time produces a different flavour profile to tea to which boiling water has been added for a few minutes, because of aromatics and the different solubilities of different compounds.

Companies spend a lot of time and energy gathering exactly this evidence. Standards bodies spend a lot of time and energy gathering this evidence.

The only subjective bit is that some people prefer their tea bitter and astringent. And some people are probably thinking of how to brew one sort of tea, while others are thinking of how to brew another sort of tea. 212.183.128.23 (talk) 17:18, 20 October 2012 (UTC)

How do we know those things? Who did the studies? Where are the results published? Looie496 (talk) 19:44, 20 October 2012 (UTC)

And a key question we can determine once we see the published studies, are these based on decent research such as double blind studies (with the tea provided at same temperature for consumption) or crappy anecdotal evidence? I would also ask who's 'people'? The British people may be famous for their love of tea, but they're far from the only people who drink black tea. No evidence has been presented that the British flavour preference for black tea is universal despite the apparent assertation that British black tea requires boiling water. Nil Einne (talk) 22:30, 20 October 2012 (UTC)

OK here's some references for you. Here's one person with a scientific explanation for why ginger tea tastes better with boiling water. --TammyMoet (talk) 09:19, 21 October 2012 (UTC) We have a standard method on Wikipedia for brewing tea: ISO 3103. And if you follow the first link on that page you find that no less a body than the Royal Society of Chemistry have indeed addressed the topic. --TammyMoet(talk) 09:22, 21 October 2012 (UTC)

The second link doesn't seem much more useful then what's already discussed here. It just a news release and seems to be largely the opinion of one random person with no sources to back up the claims. Some of them could be sourced (e.g. multiple boiled water generally having a lower oxygen content although whether that will truly make a significant difference to brewing tea I don't know), others appear to be random personal opinions (and I'm not even considering the stuff like avoid vulgar slurping). E.g. I expect in a number of countries there would be no clear cut preference for fresh milk vs UHT milk or UHT milk will even be preferred in a double blind taste test, presuming people can even tell the difference. It wouldn't surprise me if you could even find a source to demonstrate this. Note that one key point I was getting at above which I'm obviously repeating here, just because some people prefer something in some way doesn't mean everyone does, tastes can vary quite significantly and it rarely makes much sense to say one taste is 'right'. So anything which claims something is better because it produces a better tasting product should also tell you better tasting to who. The ISO standard, as our article says, is not intended to suggest thats the best method for brewing tea (as of course with most standards). It's intended to provide a standard way of brewing tea so comparisons can be made. Nil Einne (talk) 14:38, 21 October 2012 (UTC)

Why wasn't The Endeavour airlifted to its museum instead?

I saw that taking the Endeavour shuttle through the surface streets of Los Angeles was an EPIC pain in the ass; trees were cut, traffic was disrupted and it was a delicate balancing-act of sorts to make sure no damage was made by and to the shuttle.

So I'm thinking: Instead of towing it at 2 MPH for an entire weekend from the airport to its museum, why didn't they hook maybe 12 cables to 12Chinook helicopters, and have them all airlift the shuttle to its destination in probably under one hour?

See how quick that would have been? No tree would had to have been chopped down, and no traffic disrupted, right?

So how many helicopters would it really have taken? (It was my estimate of 12, right?) And the best pilots in the world would've been hired for the job to synchronize this all as flawlessly as can be.

Or if a squadron of 12 helicopters would have been too difficult, how about an airship/blimp instead? How big would the blimp need to have been or how many would have been needed?

Thanks. --75.39.142.63 (talk) 05:30, 20 October 2012 (UTC)

Sounds very risky. StuRat (talk) 05:35, 20 October 2012 (UTC)

I had assumed the entire time that it was all a publicity stunt. I have also been told by people in the know that the FAA requires the evacuation of everything under the flight path a helicopter dragging something via tow cable, which would have also been a huge pain in the ass. Also, it would take 9Sikorsky S-64 Skycranes to lift the Endeavour, ignoring the weight of additional supporting cables and such. For the Chinook, 12 sounds right, assuming it can tow as much as it can carry on board. I also wonder, did Toyota do any lobbying or offer to pay for the pain-in-the-ass work in exchange for the honor of dragging it through LA? If someone was offering to foot the bill, that would certainly make the decision far easier.Someguy1221 (talk) 05:40, 20 October 2012 (UTC)

It would be risky. Looking at Space Shuttle, it seems they weigh 172,000 lbs empty. And a CH-47 Chinook can lift 28,000 lbs. Though that is likely the rating for lifting something straight up. Once you use seven Chinooks (by my calculations: 172,000/28,000 = 6 and change), you'd have to lift diagonally. And if I'm not mistaken, that would alter how much you can lift since you're not doing it straight up. Add to that, that you would have to fabricate some sort of rigging to be able to pick up the shuttle without any odd shearing forces etc. The wings and such aren't made to bend after all since they're covered in fragile tiles. So, assuming you do all of that... Now you have 7 helicopters lifting a gigantic plane through the air over the second most populous city in the country. If anything breaks or goes wrong, you don't have much of anywhere to set the thing down in a hurry, and you possibly have (2*3*7) 42 rotor blades winging their way very quickly off in any direction they feel like going. Dismas|^(talk) 05:48, 20 October 2012 (UTC)

I would question the feasibility of having that many helicopters working in tandem. Per a few sources [17] [18] [19], it sounds like attempts were made to use 2-4 helicopters to carry a load but these were fraught with problems. While it's true these attempts were targetted at testing the feasibility of using multiple lift in general, it sounds like there were problems even when excellent helicopter pilots were used. Using seven helicopters (probably more since 7 is prime number) combined with a load you do not want to damage combined with problems Dismas mentioned sounds risky even with the 'best pilots in the world'. Nil Einne(talk) 08:34, 20 October 2012 (UTC)

What's the payload of the biggest airship ever? — Grr, that article has a section titled Heavy lifting that says nothing quantitative.—Tamfang (talk) 06:22, 20 October 2012 (UTC)

Why not partially disassemble it into sections, which can be trasnported more easily? Plasmic Physics (talk) 09:21, 20 October 2012 (UTC)

I mean, it's not as if the thing is ever going to fly again. Plasmic Physics (talk) 09:23, 20 October 2012 (UTC)

Man, where's your sense of romance? People were thrilled to see that thing lumber by. And there was much rejoicing (and free publicity) in the land, amen. Clarityfiend (talk) 09:33, 20 October 2012 (UTC)

The report that I heard said that it could not have its wings removed and re-attached due to the tiles. The wings were never meant to be taken off once put on. Dismas|^(talk) 10:21, 20 October 2012 (UTC)

Cut them off. I'm not a very sentimental person, however, I am a rational person. Rationality tells me that it was a huge waste of money and effort to transport the thing the way it was. Plasmic Physics (talk) 10:58, 20 October 2012 (UTC)

That's not rational. The whole point of transporting it to the museum was to make the whole historic artifact available at the museum, for the public and I guess for future study. If you're going to demolish it and reassemble it into a facsimile of the original, why not just scrap the whole thing and build a fibreglass replica? Then you can reuse the valuable components. Cutting it into pieces and reassembling them into a shuttle-shaped object is sentimental: either transporting the whole thing or just scrapping it and making a fibreglass replica would be the 'rational' options.86.159.77.170 (talk) 12:39, 20 October 2012 (UTC)

Simple, because a fibreglass replica is not an historical artifact, and does not achieve a the objectives of the mission. Moreover, being reaasembled does not remove its status as authentic, it may lowers its resell value. Compare it with Abu Simbel temples. Plasmic Physics(talk) 13:13, 20 October 2012 (UTC)

I think to me it all depends on where the trees were. Wnt (talk) 19:20, 21 October 2012 (UTC)

A helicopter external load can only be suspended directly under the centre of lift - for conventional single rotor helicopters that is directly below the centre of the rotor. Lateral load vectors would simply flip the helicopter over once the resultant tilt angle exceeds the dynamic rollover limit. This makes lifting objects with more than one helicopter extremely difficult, if not simply impossible. Roger (talk) 10:49, 20 October 2012 (UTC)

A simple jig could solve the center of gravity issue, albeit with a weight penalty. Suppose you have 4 helicopters, imagine an H shaped jig with the load suspended from the center and each helicopter providing lift on each corner. This is never done (AFAIK) due to the control issues Nil Einne pointed out above. Aerobatics maneuvers are entertaining at airshows but performing them above urban airspace simply isn't worth the risk. A8875 (talk) 11:05, 20 October 2012 (UTC)

It would be an enormous weight penalty. The jig would have to be very large because there are limits to how close together helicopters can safely fly. Once you get that large, it would need to be very strong to take the weight without flexing too much and breaking. Strong means heavy. I wouldn't be surprised if it ended up being heavier than the shuttle. --Tango (talk) 15:49, 20 October 2012 (UTC)

Yep, I'm pretty sure I read that the trailer rig they used to tow the shuttle through LA weighed around 120,000 pounds, and it just had to get the weight from the shuttle to the wheels. To support it by helicopter, you would need huge centilevered beams with the ends spaced far enough apart for the individual helicopters. Even if the rig didn't weigh more than the tow setup they used, it would take five more helicopters just to lift the rig.209.131.76.183 (talk) 15:00, 22 October 2012 (UTC)

And as a practical matter, the time and cost for engineering studies, construction of the rig, safety measures and other factors would probably have ended up being greater than the ground transportation that was used

Animal Eating Record

So a friend and I are trying to figure out which animal eat the highest percentage of its own body weight per day. The Wiki article for Shrew claims that it is the culprit, but there is no citation. Any sources to out there to indicate that it is indeed the shrew, or perhaps a different animal altogether.199.94.68.91 (talk) 14:48, 20 October 2012 (UTC)

Hummingbirds need to eat more than their body weight a day. The "metabolism" section in that article suggests there are insects that eat even more.88.112.36.91 (talk) 15:35, 20 October 2012 (UTC)

Edit conflict - I'm apparently wrong, but I'll post it anyway since it the concepts are true even if the conclusions isn't! Thesquare-cube law means smaller animals generally need more food in relation to their weight than larger animals. Homeotherms (loosely speaking, warm-blooded animals) also tend to need more food. So, I would expect the record to be held by a small mammal, such as a shrew. I have no sources for precisely which small mammal is the winner, though. --Tango (talk) 15:41, 20 October 2012 (UTC)

Birds are also warm-blooded, and flying probably requires more intake than does walking around. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:32, 20 October 2012 (UTC)

Flying takes more energy per unit time, but walking takes more energy per distance traveled (citation needed). Also, shrews spend a lot of time digging, which is fairly energy intensive. SemanticMantis (talk) 16:45, 20 October 2012 (UTC)

• You're basically looking at a scaling law in regards to metabolism, so smaller animals will eat more than larger ones with a similar metabolism. The shrews and hummingbirds have been mentioned. Amoebas and the like will presumably ingest large meals in one sitting. For one-time meals in the verterbrates, I would bet on the gulper. μηδείς (talk)

The leech? HiLo48 (talk) 20:37, 20 October 2012 (UTC)

You might go far with organisms that deliberately consume more nutrition than they can use. Anopheles gambiae and a jumping spider that eats it gorge on food far beyond what their bodies can process, and actually wind up pooping out completely unprocessed food (specifically blood, in both cases).Someguy1221 (talk) 01:14, 21 October 2012 (UTC)

(citation needed)? My understanding is that, in the case of mosquitoes, the red liquid released during feeding is not unprocessed whole blood, but rather a primarily aqueous, cell-depleted fraction. The mosquito can collect more nutrients from a blood meal by disposing of this liquid fraction and retaining the protein-rich cells. There's no evolutionary advantage to a mosquito taking more blood than it can use—every extra second it spends with its proboscis in some mammal's hide is an extra second where it risks getting squished.TenOfAllTrades(talk) 23:07, 21 October 2012 (UTC)

Animals which need to grow very rapidly might top the list, like the caterpillar stage of moths and butterflies. StuRat (talk) 17:20, 21 October 2012 (UTC)

Intersex Individuals and the Medical Community

How does the medical community treat intersex individuals? Gender is so ingrained in our mindset that I consider it difficult to not think in terms of the gender binary. Also, there are biological aspects that define the two sexes. Even doctors and other medical professors put race (white, black, asian, mixed), gender (male or female), or age into consideration. They may not rely on those factors completely, but they still put them into consideration. A person who is not statistically likely to get a disease may have a chance to get a disease by some atypical route. How do doctors put intersex individuals into consideration? Do they check hormone levels or something to see whether or not the individual has more of the female sex hormone or male sex hormone in order to determine the sexual/gender tendency of the individual even though the actual sex/gender is not clear-cut?75.185.79.52 (talk) 19:13, 20 October 2012 (UTC)

I suspect that the effects of their medical condition (having been operated upon to change their gender, taking injections and pills, etc.) would swamp any differences in gender. So, they may do worse than either men or women. To look at a specific case, a man who becomes a woman, and has hormones to help him grow breasts, should probably have regular mammograms. (Even men can get breast cancer, although uncommon.) StuRat (talk) 17:25, 21 October 2012 (UTC)

I think the treatment by the medical community and the degree to which gender is ingrained probably vary rather dramatically from place to place. I'm not sure the "gender binary" is very ingrained here in Thailand for example, at least in the urban areas. I don't know how the medical community deal with it in practice here, and there is probably substantial variation within the medical community, but for interest, the last time I had to fill in a medical form it said "Gender (at birth)" rather than "Gender". Sean.hoyland - talk 15:10, 22 October 2012 (UTC)

What are the choices? Maybe masculine, feminine and neuter? ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:22, 23 October 2012 (UTC)

The forms I've seen don't have choices, so you are free to put anything you want e.g. "Can't remember, I was a baby". Sean.hoyland - talk 12:13, 23 October 2012 (UTC)

Maybe they switched from "Sex" due to curb responses like, "Three times a week" and such. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:15, 23 October 2012 (UTC)

Mysterious insect invasion

Our home (exterior) has been visited by thousands of these winged insects that are primarily black with orange "pinstriping". They are approx. 20mm long at maturity, and apparently seeking out warmth, as autumn descends here in upstate NY. Thanks in advance for your help. PS: I have jpg photo, but haven't figured out how one pastes it here. --Paolo38 (talk) 21:18, 20 October 2012 (UTC)

Do they look like this? Deor (talk) 21:53, 20 October 2012 (UTC)

I've had maybe a dozen of those bugs in my house in the last few weeks. Apparently they come inside when it gets too cold outside. On the plus side, they are easy to catch. I tend to release them back outside. Unfortunately a couple managed to torch themselves on my halogen lamp, making a horrible stench. StuRat (talk) 17:13, 21 October 2012 (UTC)

Solar Flare, Time Capsule Computer

I'm thinking of writing a fanfiction, and I have some questions. I care a surprising amount about realism in a story that takes place in a world populated by talking magical ponies.

Could a single solar flare (or coronal mass ejection or whatever) destroy almost all of the technology on the far side of a planet without killing everypony on the close side? Also, what effect would it have on ponies with cybernetic implants? What if they're connected to the power grid at the time?

Also, my story involves having some kind of underground computer system that was successfully built to continue running for centuries after the end of civilization. This would involve it, being self-repairing, incredibly long-lasting, or some combination of the above. It also has one or more emulated pony running on it, so it doesn't doesn't have to be all that simple to repair. Technology is somewhat more advanced than we have now, but from what I understand, that would just make computers that much harder to repair. Magic exists in the setting, but I'd like a better explanation than "a unicorn did it". Is this at all feasible? If so, how large would it have to be? What kind of natural power source would last that long without changing and be underground? A geyser? Geothermal power? Nuclear power?

— DanielLC 23:20, 20 October 2012 (UTC)

If I (an Engineer) was requested to design & build an electric generator that would run unattended for centuries, I would go for nuclear isotope poweredthermionic conversion. Once can choose a suitable isotope with a half life of centuries, and use it to heat a metal cathode vacuum thermionic generator. There is literally nothing to fail, wear out, or chemically change in such a generator, apart from fission products (which are easily understood and contained). About the only failure mode is seal failure leading to loss of vacuum. However the electronics industry has about 100 years experince in making virtually failure proof glass to metal seals. Reliability is always dramatically improved by using multiple small generators rather than one large one. Energy conversion efficiency will be very low though - perhaps 1% or less. Ratbone121.215.41.218 (talk) 01:55, 21 October 2012 (UTC)

I'm struggling to see how realism is going to be compatible with talking magical ponies. This is a science reference desk. Only you can know with what defences and attributes your imaginary ponies will be endowed, but I think it will be safe to say they will struggle to overcome the threats you throw at them, but the hero/heroine will emerge victorious in the end.--Shantavira|^{feed me} 11:49, 21 October 2012 (UTC)

Sigh. I miss The Outer Limits. Wnt (talk) 15:47, 21 October 2012 (UTC)

You have realism through Magic A is Magic A andLike Reality Unless Noted. Since there are no unicorns in the computer system, they can't do magic, and it will work through the physics that rule real life. Magic might help for producing the stuff to begin with, but that's it. —DanielLC 20:01, 21 October 2012 (UTC)

• Of the power options you mention, I think geothermal power makes the most sense - provided you're not on a fault line, it shouldn't be broken, barring greenhouse disasters the difference in temperature won't go away, and a thermocouple, so far as I know, is something so basic, with no moving parts and which could be made to resist corrosion, that I am hard pressed to imagine any mode of failure. And as a bonus, you've already specified the power source be underground anyway. Wnt (talk) 15:51, 21 October 2012 (UTC)

• You might be interested in this actual project to build an underground clock meant to last 10,000 years: http://longnow.org/clock/. It relies on solar power and people to wind it up, which seems rather silly for a clock, but might work well for a computer, provided it only needs to run when people are there to wind it. Also, how nicely steampunk. StuRat (talk) 17:08, 21 October 2012 (UTC)

• It's designed to run without any external assistance, and emulating a pony is much, much more sophisticated than counting. — DanielLC20:01, 21 October 2012 (UTC)

• Not really. Clocks that showed leap year, days in each month, phases on the Moon, rising and setting of the Moon and Sun, and movements of constellations had high degrees of complexity to them. This could also be used to simulate the movements of a pony. Clockwork is clockwork.StuRat (talk) 22:35, 21 October 2012 (UTC)

• Mechanical systems are Turing complete. While you could, in principle, build a larger version of the 10,000 year clock that simulates a person's brain, it would have to be the size of a mountain and have a reaction time measured in hours. That would not work for the purposes of this story. —DanielLC 23:41, 21 October 2012 (UTC)

October 21

Thermionic emission

Our article on Thermionic emission states that

Guthrie discovered that a red-hot iron sphere with a positive charge would lose its charge (by somehow discharging it into air). He also found that this did not happen if the sphere had a negative charge.[1]

I would expect this to be just the opposite, so I asked at Talk:Thermionic emission#Why lose positive charge? Please reply there. Thanks! — Sebastian 14:25, 21 October 2012 (UTC)

Ultra-dense deuterium, Rydberg matter, cold fusion, etc.

Our article on Rydberg matter is just incredible, and looks well supported by sources - giant atoms at highly excited states which intermingle, which seems pretty similar to saying, a bunch of positively charged ions knocking around in a cloud of extremely high energy electrons.

But it was proposed for deletion by people claiming it was fringe matter, and following this, I find that the author was (apparently) one of the researchers involved in somehow collapsing this stuff to make ultra-dense deuterium, an article since redirected because the idea is absurd - stuff with a density of 140 kg/cm³. Apparently it is a "quantized line vortex" (a phrase surely destined for sci-fi glory!) of deuterons acting as bosons in a condensate. (Bose-Einstein condensate I assume?). Someone in Reno even proposed it as an explanation for how cold fusion works. [20] But apart from that last, the papers were coming out of one group in Sweden, of which our User:Holmlid was a member. Fortunately trees are scarce in the virtual world or I do believe our deletionist friends would have nailed him to a ruddy cross; in any case he was successfully beaten off and hasn't edited WP since.

However, I see that the one group made many publications, and now there is now a different group discussing this stuff seriously [21]. Now mind you, my own level of competence is such that I don't even understand why a Bose-Einstein condensate isn't prone to undergo fusion, if it isn't. I don't know if this is a good journal, though Journal of High Energy Physics cites an impact factor of 5.8, which in biology I know is very respectable. So I'd like to restore an article on ultra dense deuterium, but I could surely use some encouragement and more eyes on the topic.

Besides, this is just about the coolest thing I've found on Wikipedia all year. Wnt (talk) 16:53, 21 October 2012 (UTC)

Your question, I gather, is whether "ultra dense deuterium" is a sufficiently notable subject to justify a freestanding article. Looie496 (talk) 17:20, 21 October 2012 (UTC)

Hmmm, not precisely. The WP mechanics are something I can decide on my own (unless someone beats me to it!) - what I'm really interested in is more the issue forbidden to proper WP editing consideration, namely, are these observations actually real and true? Today I learned about two different kinds of electron-bound "matter" with lower and higher densities than I'd ever heard of, unless it's all bogus. But whether they are supported by good publications is the most accessible surrogate for that. Wnt (talk) 17:26, 21 October 2012 (UTC)

You could get this sort of density by high pressure. Another way is extreme magnetic fields, in which case you get long chains of atoms stretched along the magnetic field lines. Also note that the content was merged and not just axed, appearing at deuterium#Ultradense deuterium Graeme Bartlett (talk) 10:00, 22 October 2012 (UTC)

Sorry - you're absolutely right. Wnt (talk) 17:41, 22 October 2012 (UTC)

Edible fungus

“ 'Forty-two pounds of edible fungus

In the wilderness a-growin

”

This is a borderline Language Desk question, but on balance I decided to ask it here. I notice that edible fungus redirects to edible mushroom. Is it really the case that every edible fungus is a mushroom? I tend to think of mushrooms as fungi that have a well-defined "head". --Trovatore (talk) 22:12, 21 October 2012 (UTC)

How about truffles ? Our article calls them a "subterranean mushroom", but that's not what I think of as a 'shroom. StuRat (talk) 22:29, 21 October 2012 (UTC)

How about yeast? —Tamfang (talk) 23:00, 21 October 2012 (UTC)

It probably is more of a language question. I dare say that edible fungus is probably the more technically correct term, but edible mushroom would be the term used and understood by 99% of the english speaking world. Cloud ear fungus is another one which I would struggle to call a mushroom, but the article says it is known as black Chinese fungus (or mushroom).. There is also a difference between culinary terms and strict botanical terms, such as fruit and berry have quite different meanings in culinary use as opposed to botanical use. Vespine (talk) 00:24, 22 October 2012 (UTC)

Cheeses contain edible fungi: Penicillium roqueforti is used in Roquefort blue cheese, and Penicillium candidum is used in making Brie and Camembert cheeses. --Jayron32 01:00, 22 October 2012 (UTC)

Aspergillus oryzae is used in the fermentation of various Chinese and Japanese foodstuffs. --Jayron32 01:02, 22 October 2012 (UTC)

Quorn is a popular food made from edible fungus, but members of Ascomycota are not usually considered mushrooms (e.g. fusarium species grow in your sink drain). The man ingredient is labeled as a mycoprotein. So, no: not every edible fungus is a mushroom, but note that mushroom is is a common term with no taxonomic weight, and usage will vary. SemanticMantis (talk) 01:03, 22 October 2012 (UTC)

("Mushroom" is sort of like "bug." Both are common names that are essentially ill-defined, but the terms also can carry taxonomic meaning in the right context, as in true bugs. ) SemanticMantis (talk) 01:06, 22 October 2012 (UTC)

So I wasn't really talking about molds. I'm thinking of things like white fungus soup, where the fungus is macroscopic but doesn't seem mushroomy to me. --Trovatore (talk) 02:50, 22 October 2012 (UTC)

Are there any fungi that are not even remotely mushroom-like but are eaten whole as the food itself? As in, the food is neither a fungal extract nor a fungus mixed with many other things. I rather enjoy cooked mushrooms, but I'd never eat a fistful of yeast. Someguy1221 (talk) 02:46, 22 October 2012 (UTC)

How about just the "blue" with no cheese?GeeBIGS (talk) 02:52, 22 October 2012 (UTC)

Again, I'm not interested in molds. --Trovatore (talk) 02:56, 22 October 2012 (UTC)

Why aren't you interested in molds? You asked for edible fungi that aren't mushrooms. Molds are clearly fungi and clearly not mushrooms (i.e. no one would classify a mold as a mushroom, and everyone classifies them as fungi), and many are quite edible. You're changing the rules in the middle of the game. --Jayron32 04:45, 22 October 2012 (UTC)

Molds are maybe fungi in the same sense that tomatoes are fruit. They aren't fungi in the everyday understanding of the term. --Trovatore (talk) 07:05, 22 October 2012 (UTC)

Huh? I've seriously never heard that proposed that way. Molds clearly belong to the fungus branch of the tree of life, and in my entire living memory, I've never heard anyone propose that they didn't. Seriously, if molds aren't fungi, what are they?!? --Jayron32 22:53, 22 October 2012 (UTC)

They're molds.

Look, I agree, biologically, they're fungi. But the common usage of the term fungus does not really encompass molds, or yeasts either, except perhaps when you're talking about fungal infections. --Trovatore (talk) 22:57, 22 October 2012 (UTC)

OK, then we're going to have to agree to disagree then; what it sounds like you are proposing to me sounds like (subbing out words) "the term mammals does not really encompass cats, or dogs either". I've never considered that anyone wouldn't think that "mold" was a subset of "fungus" or that they occupied mutually exclusive categories in any way. Clearly you do, and clearly I don't. Neither of our feelings on this are apparently self-evident, just as you've never heard anyone consider a mold a fungus, I have never heard anyone who didn't, on any level, either colloquially or technically. It sounds, to me, like someone claiming that cardinal is not a shade of red or that trees are not plants. --Jayron32 16:55, 24 October 2012 (UTC)

You mention yeast. The term brewer's yeast is often used to indicate yeast taken as a dietary supplement, which is pretty much "just yeast", if I'm not mistaken. In fact, we have the article Nutritional yeast. I know that you said no extracts, but there's always vegimite, which is more or less pure fungus, though the cells themselves have been disrupted. Buddy431 (talk) 04:36, 22 October 2012 (UTC)

It looks like you're responding to Someguy1221, who seems to be taking much the same tack I had in mind. Edible fungus you might find 42 pounds of in the wilderness a-growin', but not mushrooms. Something like the snow ear fungus used in white fungus soup, for which our article gives as an alternative name the "white jelly mushroom", but which it seems unlikely anyone would call a "mushroom" if they found it while walking in the woods. Or our article on Trametes versicolor calls it a "mushroom" repeatedly, but it sure doesn't look like a mushroom to me. Are these really "mushrooms"? Is there any clear demarcation that makes them such, in opposition to common usage? --Trovatore (talk) 07:41, 22 October 2012 (UTC)

Yes, the clear demarcation that makes the Trametes fungus a mushroom is that they are Agaricomycetes these are also known as "bracket fungus", or "bracket mushrooms". Our article mushroom explains that this order, as well as Basidiomycota, is what is usually meant by "mushroom". The example I gave above is from the Ascomycota, which is not usually considered a mushroom order taxonomically, but some members are considered mushrooms for culinary purposes. Some of the key features of a "classic" mushroom are the stipe and the pileus. But this has really just gotten into folk taxonomy at this point, if you want to say that fungi molds are not fungus. Also, I invite you to reconsider the plausibility of a 42-pound haul of mushrooms. Just this year, a hunter told me of his (albeit lifetime record) 60 pound haul of morels. SemanticMantis (talk) 13:00, 22 October 2012 (UTC)

I'm confused — are you saying I said it was implausible? I don't see where. (The forty-two pounds thing is a literary allusion, BTW.) --Trovatore (talk) 22:44, 22 October 2012 (UTC)

Yes, when you said "Edible fungus you might find 42 pounds of in the wilderness a-growin', but not mushrooms." -- I thought you were questioning the plausibility of finding 42 pounds of mushrooms growing in the wilderness. It seems I was mistaken, but it looks like you have plenty of good answers here: to sum up: no, not all edible fungi are mushrooms :) SemanticMantis (talk) 15:12, 23 October 2012 (UTC)

Arg. The most recognizable mushroom on Earth, and I never, ever see them. Not even the false ones. I wish I knew his secret... Wnt (talk) 17:45, 22 October 2012 (UTC)

Corn smut - not a mushroom, some consider it edible in more or less unaltered form. Besides it is such a fun word. Rmhermen (talk) 16:14, 22 October 2012 (UTC)

For all of you who didn't pick up on it — the 42-pounds quote at the top of this thread is a quote from Homer Price, a work of fiction. Nyttend (talk) 12:04, 24 October 2012 (UTC)

October 22

Asians in science and math

Why are there so many Asian scientists/mathematicians? --168.7.239.202 (talk) 05:03, 22 October 2012 (UTC)

Because there are a lot of people in Asia. It is the most populous continent by a long shot. 3/5ths of all people on earth are Asian, give or take a few. --Jayron32 05:12, 22 October 2012 (UTC)

But there are disproportionately more Asians in those fields than in other fields. --168.7.239.102 (talk) 05:18, 22 October 2012 (UTC)

Do you mean people of Asian descent in developed countries? I think you'll find that in most developing countries, including Asian ones, proportionally there are few people in those fields then in developed ones because there isn't enough money. Nil Einne (talk) 05:29, 22 October 2012 (UTC)

And on the disproportionate. Are more than 60% of the world's mathematicians and scientists from Asia? I'd like to see where that is reported before we start explaining why. It does no good to explain a concept that hasn't even been established as true yet. --Jayron32 05:33, 22 October 2012 (UTC)

I see that you're at Rice University. It's likely that immigrants' children in general go disproportionately into STEM (science / technology / engineering / mathematics), and Asians are the most visible of those at university. —Tamfang (talk) 05:31, 22 October 2012 (UTC)

I perused our article on STEM fields, which linked to a publication from the U.S. Department of Commerce, Education Supports Racial and Ethnic Equality in STEM, which confirms the assertion implied in the original post, with data to back it up: "non‐Hispanic Whites and Asians are much more likely than other minority groups to have a bachelor’s degree..." (corresponding to an overrepresentation in technical jobs related to science, engineering, and technology). The full report outlines a lot more data, and authoritatively speculates on some root-causes, concluding with the fairly benign policy recommendation to improve educational opportunities for all underrepresented demographics. Nimur (talk) 05:38, 22 October 2012 (UTC)

See also Race and intelligence.--Shantavira|^{feed me} 07:18, 22 October 2012 (UTC)

Nothing to do with race and intelligence. Far more to do with motivation, ambition and effort. That's in my experience anyway. Children from immigrant families tend to work harder at school than the locals. HiLo48 (talk) 07:28, 22 October 2012 (UTC)

They are the locals once they've immigrated. Particularly if the immigration occurred in the previous generation. -- Jack of Oz ^[Talk] 09:11, 22 October 2012 (UTC)

I think you're leaving out parental pressure as a force as well — this is well-known and in fact quite commented on. See the whole flap on the Battle Hymn of the Tiger Mother from last year. I am not sure that the children are any more ambitious than any other children — but they are certainly pressured to perform. A similar factor is quite obvious in other sub-cultures of this sort (e.g. Jewish lawyers and doctors). My experience working with children in educational contexts (clearly anecdotal, but not baseless) is that groups of children are more or less similar across cultures in their aptitude for frittering away time and lack of interest in the tedious, but the overall household's attitude towards education makes the biggest differences across groups. --Mr.98 (talk) 11:58, 22 October 2012 (UTC)

Days, hours, seconds, angles

Not sure whether it belongs here or into some other reference desk. What is the reason that we have 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day and not factors of 10 or 100 (with modified definitions of second/minute/hour/day...)? Same for angles, why do we have 360 degrees in a full circle? Are there other examples? I understand that in science usually people would use SI units (or whatever system is convenient for their use) and radians for angles, but this question is about commonly used units. Also, are there any cultures that use different systems to measure time, angles,...? bamse (talk) 07:41, 22 October 2012 (UTC)

The History section of Degree (Angle) has some good insight. HiLo48 (talk) 08:02, 22 October 2012 (UTC)

One factor is that you want a number which can be easily divided by many low numbers. 10 and 100 can't even be divided by 3. On the other hand, 24 hours can be divided into 2, 3, or 4. So, you could have 2, 3, or 4 shifts of guards, without having to teach your guards fractions so they would know who they needed to show up. 60 can be divided by 2, 3, 4, 5, and 6 (as can 360), so even better. StuRat (talk) 08:33, 22 October 2012 (UTC)

You might also be interested in decimal time, which was introduced after the French Revolution, but didn't last long. It always seemed odd to me that the metric system didn't feel the need to do anything about our messy, non-decimal units of time, that being one of the most basic dimensions of measurement. StuRat (talk) 08:38, 22 October 2012 (UTC)

it did. Powers of 10 seconds are in common use Kilosecond Femtosecond 157.193.175.207 (talk) 12:34, 22 October 2012 (UTC)

How about for astronomy ? A terrasecond is less than 32,000 years, so not of much use to astronomers. StuRat (talk) 23:27, 22 October 2012 (UTC)

The age of the universe is less than an exasecond. Orders of magnitude (time) 81.11.174.45 (talk) 05:54, 23 October 2012 (UTC)

As for other units, angles can also be measured in gradians, where a circle is divided into 400 parts instead of 360. This does at least give you 100 units in a right angle. In civil engineering, angles are also measured in terms of slope or grade. Those aren't directly proportional with radians, degrees, or gradians, and are generally only useful for angles less than 90° and greater than -90° (because you hit infinite values at 90° and -90°). StuRat (talk) 08:44, 22 October 2012 (UTC)

It's worth noting that the sexagesimal system is very, very, very old. It commonly gets dated to the Sumerians but that's just another way of saying "the earliest written records we have use it — it may be even older." It has numerous practical advantages when it comes to quick calculation and division, as previously noted, of the sort that would have been very useful to people in pre-calculating machine ages (i.e. almost all of human history). The relevance of measuring angles to measuring time is fairly clear if you consider early time-keeping systems (e.g. sundials). Decimal systems are relatively new in most cases; one might suggest that their prioritization of precision and easy orders of magnitude over division indicates a considerable difference between the concerns of the modern world and those of the deeper past. --Mr.98 (talk) 14:46, 22 October 2012 (UTC)

Thanks a lot! bamse (talk) 19:46, 22 October 2012 (UTC)

What noise do germs make?

What noise do germs make? My 4-year-old son asked me to post this question onto Reference Desk. He intended it as one asks, 'What noise does a cow make?' or 'What noise does a duck make?', but you may interpret 'noise' more broadly if you wish, perhaps as any physical communication with other organisms including humans. By 'germ' he meant any micro-organism, as is his usual practice. 82.31.133.165 (talk) 08:52, 22 October 2012 (UTC)

I suspect that any sound they make would be too high of a frequency for us to hear. I don't believe they communicate with each other, but they probably do make some very low volume, high frequency sounds accidentally. Like us, they might make sounds during digestion, for example. Those capable of movement would also make noise as they whip their flagella around, etc. However, there are some retroviruses which neither digest nor move on their own. They are just like a form letter which reproduces simply by convincing something else to copy it. Those should be completely silent, except for when they are actually being copied or moved about by external forces. I wonder if anybody has recorded the sounds germs make and shifted the frequencies/boosted the volume so we can hear them. StuRat (talk) 08:57, 22 October 2012 (UTC)

Well, it seems the technology that would allow us to 'hear' bacteria is experimental at best. (I'm interpreting 'germs' as equivalent to 'bacteria' - I suspect that it would be even more difficult to 'hear' viruses, since they are more inert and often many orders of magnitude smaller.) Here is an article about the development of a Nano-ear, which can hear sounds on the scale at which we expect that bacteria would produce sounds. There's a link in the comments to an ongoing study at University of Southern California called E. Musicii, which states its aim to measure environmental effects on E. Coli bacteria by listening to the sounds they produce under various stresses. Now, from what I can gather from reading the report (and bearing in mind that this is being filtered through my rather average GCSE Biology), they cant't actually hear the bacteria, but they can see the movements of the flagella, and can translate these into human-audible tones. What they've noticed is that in normal conditions the bacteria produce a random mish-mash of tones at varying frequencies. (Interestingly, they all seem to be variations on a sine wave, although that's not commented on as far as I can see. I'll come back to that in a bit.) However, when they introduce some stress into their environment, such as excess salt, the bacteria seem to start to harmonize - that is, they start to rotate their flagella at similar frequencies, and hence the sound produced can be likened to 'singing'. In some ways, you could think of this like humans in a zombie movie. Initially, people are moving around and talking randomly - there is a general hubbub of uncoordinated noise. However, on the introduction of 'environmental stress' (zombies), the noise harmonizes as screaming.

So, how to explain this to your son? Well, he should probably know that no-one has yet 'talked' to a bacteria. Who knows, though, maybe he will be the first! But we do know that some bacteria have rope-like arms (flagella), and we think that these make a noise. You can probably demonstrate this: Try taking two bits of rope (each about the length of one of your arms would be good) and tying some thin paper (tracing paper should work well) to one end. Now you can whirl these around (might be best to be outside at this point) and hopefully the paper should make a noise. You should also be able to show how, by whirling faster or by making the rope shorter, you can change the sound you make. This is how we think the flagella would make a noise. Now go back inside and find a sine-wave generator. (I bet there's a iPhone app.) Explain that this noise is simply the same noise as you were making with your rope-and-paper flagella, but sped up many times. Show how you can make slooooow, loooow sounds, and fast, high ones. Thus you can explain that this is how we think that bacteria sound - and that they can change the sounds they make by either making high sounds or low sounds.

Best of luck, and I hope to hear from your son in 50 years time when he wins his Nobel Prize for becoming the Doctor Dolittle of the germ world! - Cucumber Mike (talk) 09:50, 22 October 2012 (UTC)

Bacteria mostly communicate between themselves using chemical signals. As for sound, as a rule of thumb, an object can only make and perceive noise at a wavelength up to its body size. For an large-average bacterium, body size is about 5 micrometer. This results in the lowest possible frequency of around 64000 kHz. For the absolutely amazing Epulopiscium fishelsoni with a size of up to 700 micrometer (n length), the lowest frequency we can expect it to produce is 450kHz. Human hearing stops (depending on age and AC/DC) at around 20kHz. So there is little chance that humans will ever hear the noise (if any) of bacteria directly. --Stephan Schulz (talk) 10:14, 22 October 2012 (UTC)

An object can only make a noise at a wavelength up to its' body size? Really? What utter nonsense! If a surface moves at frequency x, then energy at frequency x is coupled into the air in contact with it, as the surafce necessarily whacks air molecules that strike it. Size of the surface has nothing to do with it, except in so far as it affects the efficiency of coupling (at low frequencies) and interference effects giving a directional effect (at high frequencies. I have in front of me now, stereo speakers having 130 mm diaphrams in the bass drivers; these are in appropriately designed boxes about 200 x 450 x 250 mm. A wavelength of 130 mm in air corresponds to a frequency of 340 m/s divided by 0.13 m ie 8460 Hz - a high trebble note! In fact they are close to flat down to 50 Hz - a low bass note. I myself, a real live male human, have a mouth about the usual size - about 100 mm or so wide open. I can loudly sing a bass note. An object can only percieve sounds up to a wavelength up to its size? Again, what utter nonsense! Go find a typical microphone - you can buy in any decent music shop a microphone less than 100 mm long with a response down to 16 Hz. Even your cellphone can pick up sounds down to 300 Hz - a wavelenth around 100 times the size of the phone. Keit 60.228.242.118 (talk) 11:35, 22 October 2012 (UTC)

Another factor, of course, is that the speed of sound in air is not the same as the speed of sound in a bacteria, or in a human's vocal chords, and so on. For effective coupling - in other words, for efficient production of sound, we can approximately say that the wavelength should correspond to the object size - but this is not a strict physical law. Nimur (talk) 01:49, 23 October 2012 (UTC)

• There was a bit about this a few years back - recognizing cancer cells by how they scream when exposed to light (I'm not making this stuff up... I never need to!) [22][23] - see [24] (The sound of the cell itself is focused on at [25][26][27]...) But I only heard about it in eukaryotic cells - there might be bacterial data with more digging. Wnt (talk) 17:16, 22 October 2012 (UTC)

Punk rock noise. Clarityfiend (talk) 22:33, 22 October 2012 (UTC)

The word "noise" is redundant there. :-) StuRat (talk) 23:22, 22 October 2012 (UTC)

Yeah, horrible, innit. Don't you just yearn for the old songs, like It'sy Bit'sy Tee'nie Wee'nie Yell'ow Pol'ka D'ot Bi'kini. -- Jack of Oz ^[Talk] 09:17, 23 October 2012 (UTC)

You know, Jack, in my watchlist, the question says "what noise to germs make?" and your edit summary says "yearning", which makes as much sense as anything else. --Trovatore (talk) 09:34, 23 October 2012 (UTC)

Pay it no mind. Onward to glory. -- Jack of Oz ^[Talk] 11:01, 23 October 2012 (UTC)

Angel Oak

On your page Angel Oak you state, what I have found at the Angel Oak site in Charleston, SC, that the Angel Oak is about 300-400 years old. Now on the Angel Oak web site and your site of List of Oldest Trees it states the Angel Oak is 1,500 years old. I don't know the age of the tree but there is a big difference between 400 and 1,500 years. I am still researching the age but if you can find the answer that is closer to what the age is could you (a) let me know and (b) correct it on one of your two locations (the two I have found anyway). Thanks. — Preceding unsigned comment added by 165.214.14.23 (talk) 15:19, 22 October 2012 (UTC)

That's Angel Oak and list of oldest trees for the lazy. At a glance, the 300-400 year estimate is covered by this ref: [28], but we can probably find more reliable sources... SemanticMantis (talk) 16:49, 22 October 2012 (UTC)

This reference may explain the uncertainty about its age as "...heart rot makes it impossible to obtain accurate core samples". Obviously both articles need some editing. hydnjo (talk) 02:17, 23 October 2012 (UTC)

Crab breathing

Do some crabs have both gills and lungs? Do some have only lungs? Only gills? Freshwater crab#Description and life cycle says In addition to their gills, freshwater crabs have a "pseudo-lung" in their gill chamber that allows them to breathe in air, but that's about all I can find.

In particular, what about shore crabs on a saltwater shore?

Crab#Evolution says Crabs are found in all of the world's oceans. Does this mean just the shores of all the oceans, or does it mean there are crabs that spend their entire life on or under the ocean surface? Duoduoduo (talk) 17:38, 22 October 2012 (UTC)

For the last, there is a crab species that lives only at hydrothermal vents, described here [29]. It's hard to find a ref that specifically says this, but I doubt they ever come anywhere near the surface. SemanticMantis (talk) 19:00, 22 October 2012 (UTC)

I believe there are no crabs with true lungs, only gills. Many types of crabs live in deep water -- some in very deep water: the large-clawed spider crab from the Gulf of Alaska holds the known record, I believe, being found down to 11,000 feet. (The thought of an Alaskan king crab coming up onto the beach is kind of terrifying!) There are no crabs that spend their lives on the surface -- they are all bottom-walkers. Looie496 (talk) 19:02, 22 October 2012 (UTC)

This pdf, "freshwater crabs in africa" [30] has a little more info on their behavior and morphology. As Looie alludes, the "pseudo lung" is just a specialized gill. The article "Role of Lungs and Gills in an African Fresh-Water Crab, Potamonautes warreni (Decapoda: Potamoidea), in Gas Exchange with Water, with Air, and during Exercise" seems to be a good authoritative source, if you have access to JSTOR [31]. SemanticMantis (talk) 19:07, 22 October 2012 (UTC)

Horseshoe crabs, which aren't really crabs, have book gills. StuRat (talk) 23:19, 22 October 2012 (UTC)

Crab eyestalks

Do all crabs (both true crabs and otherwise) have eyestalks? The stub article eyestalk doesn't even mention crabs. The article on the non-true crab porcelain crab says they have them and implies that at least some true crabs do too, but that's all I can find. Duoduoduo (talk) 17:46, 22 October 2012 (UTC)

The horseshoe crab isn't really a crab, and it appears to lack eye-stalks. StuRat (talk) 23:15, 22 October 2012 (UTC)

Pale Male's longevity

Does anyone have any thoughts as to how the famous hawk, Pale Male has lived for so long, when so many of his numerous mates and offspring appear to have had substantially shorter lives? He seems to have been one of the first urban hawks and continues to remain as always, at an advanced age for his species in the wild, while others have succumbed to the hazards of their habitat. Just plain luck? Or that hundreds of humans have his back? --Kurt Shaped Box (talk) 19:56, 22 October 2012 (UTC)

Well, your source says that lifespans of 30 years are known. As a rule, any wild animal that is being given human help should live longer, if the humans know what they're doing. Also, since it's a sample size of one, we can't rule out selection bias - there might be some other urban hawks you never heard of because they died after a few years. Lastly, it's within the realm of probability - for a single hawk to live to the maximum lifespan could happen, regardless of any other circumstance, simply by chance. (I also consider the faint possibility that a dead hawk could have been replaced to keep a tourist attraction, but I assume that the feather patterns and other physical traits are distinctive enough to the hobbyists who watch the nest and take high quality photos to make this exceedingly difficult.) Wnt (talk) 21:19, 22 October 2012 (UTC)

Nature is red in tooth and claw. In any animal population which is roughly "stable", each adult, during the course of its whole life, will on average raise just one single successful progeny. So for every animal which has 'several' offspring each year, the completely normal natural thing to happen is for the majority of them to die. This realization is what led Charles Darwin to realize the power of natural selection. Vespine (talk) 21:30, 22 October 2012 (UTC)

Astrology

I use Wikipedia regularly & am very impressed. However, I am concerned about the page on Astrology. This page seems especially biased to me, referring to astrology as pseudoscience without any factual basis. Astrology is already handicapped in today's world & we do not need Wikipedia exacerbating the situation. — Preceding unsigned comment added by Zen99 (talk • contribs) 21:30, 22 October 2012 (UTC)

I hate to break it to you but the article is accurate. Astrology is completely pseudoscience. Most people have a "pet" pseudoscience they love to believe in and champion, and think is NOT pseudoscience, I personally used to have many, including astrology. But your mission now, if you chose to accept it, is try to learn how and why people believe in astrology and why they are wrong. Vespine (talk) 21:35, 22 October 2012 (UTC)

Let me get you started, try this article: Confirmation bias.. Also, if you are genuienly interested in learning, and I hope by being here you are showing that you are, find and read this book: Demon haunted world. Vespine (talk) 21:47, 22 October 2012 (UTC)

If I might focus that a bit, the primary guidance in Wikipedia on subjects such as astrology is WP:FRINGE and in its most basic form that policy reflects Wikipedia's general point of view that articles should reflect prevailing scholarly opinion. As Vespine says, the prevailing scholarly opinion is that astronomy astrology is pseudoscience. Regards, TransporterMan (TALK) 21:52, 22 October 2012 (UTC) <Self-dope-slap> — TransporterMan (TALK) 13:59, 23 October 2012 (UTC)

I hope you mean "astrology" and not "astronomy." Astronomy - the scientific study of stars and stellar physics - is widely regarded to be a real science. Nimur (talk) 21:58, 22 October 2012 (UTC)

And if you need someone to clarify the difference, ask a cosmetologist. :-) StuRat (talk) 23:05, 22 October 2012 (UTC)

It's as valid as crystal dangling, reading tea leaves, using the lines on the hand to predict fortune and crystal ball gazing. Get over it. It's bunk and has no place in society other than to pacify the weak-minded. — Preceding unsigned comment added by 217.158.236.14 (talk) 08:26, 23 October 2012 (UTC)

On a related subject - is there a name for the "I agree with the sceptics that the vast, vast majority of it is bunk/woo/hooey/etc., however there are a small number of legitimate practitioners who can really can make it work" effect? I've heard this said of many different methods of divination and alternative medical treatments for which there is little-to-no scientific evidence of efficacy... --Kurt Shaped Box (talk) 23:32, 22 October 2012 (UTC)

Well, there are fields which have legit practitioners as well as quacks, like chiropractic doctors. I fully believe they can adjust your spine to help a sore back, but cure cancer ? Not so much. StuRat (talk) 23:56, 22 October 2012 (UTC)

One simple fact about astrology is that it's based on ancient gods (typically Roman and Greek). Therefore, if you don't believe in ancient mythology, it seems odd to believe in their predictions. StuRat (talk) 23:07, 22 October 2012 (UTC)

What if the classical gods were invented to explain the true effects detected by astrology? —Tamfang (talk) 03:09, 23 October 2012 (UTC)

Then all the different forms of astrology would need to agree. They do not. StuRat (talk) 05:10, 23 October 2012 (UTC)

Come now, every science has had some wrong paradigms now and then. —Tamfang (talk) 20:56, 25 October 2012 (UTC)

How dare you defame the gods! I demand that you sacrifice a hecatomb on the altar of Apollo for this heresy. --140.180.242.9 (talk) 04:22, 23 October 2012 (UTC)

How much is a hecatomb in the English System? ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:20, 23 October 2012 (UTC)

Just to be contrarian, I'll point out that lack of scientific evidence doesn't mean something isn't true ;) If you enjoy astrology, and feel that it adds something valuable or meaningful to your life, why should you care if it is considered a science by the scientific community? Science is not the only valid way of obtaining insight into the human condition. Just ask any humanist, artist, philosopher, etc. Really, the only reason we scientists get annoyed with psuedosciences is because they often claim to be using scientific reasoning when they are not. SemanticMantis (talk) 23:25, 22 October 2012 (UTC)

I think many scientists get annoyed with astrology for other reasons, and I don't even know if what astrologers say should be considered a claim of scientific reasoning. Anyway, the article can be discussed at Talk:Astrology but note it's listed at Wikipedia:Database reports/Talk pages by size with 4.1 MB of discussions. It's a high profile article and has been discussed extensively. You will probably find it impossible to get consensus for removing the well-sourced statement that astrology is a pseudoscience. Some articles receive far less attention and may be more colored by the views of a single editor but that's considered bad in Wikipedia. Maybe an article like John Frawley (astrologer) (current version) is more to your liking but merely posting the link here may get others to change that. PrimeHunter (talk) 23:52, 22 October 2012 (UTC)

As a humanist, I vehemently disagree. If the only reason for believing in something were "it makes me feel good" instead of "it's true", modern society would be impossible. In a high-tech world where countries have the weapons to destroy civilization, it's downright dangerous to have scientists, engineers, or politicians making decisions based on their own personal fantasies instead of logical reasoning. What if the US president decided to attack China because he sees some astrological sign? (After all, that's why William the Conqueror invaded England.) What if a nuclear power plant designer decided not to include a safety mechanism based on the good fortune he expects from astrology? On a smaller scale, what if one of your closest relatives refuses to seek medical help for cancer because, according to a horoscope, he expects good health soon in the future?

Read the article on secular humanism, and you'll learn more about what they believe in. They explicitly reject all superstition, including religion, because it hampers progress towards a better world. Your comparison with artists is invalid because artists don't make claims that unambiguously contradict scientific evidence. Neither do most philosophers, although there's no shortage of philosophers who engage in pseudoscience and make stuff up as they go along. --140.180.242.9 (talk) 04:22, 23 October 2012 (UTC)

What's your evidence that William the Conqueror invaded because of an astrological sign? My understanding was that his main reason for invading was (unsurprisingly) that he wanted to rule England. He felt he had a better claim than Harold II, and he'd employed a number of ruses (including tricking Harold into taking an oath on holy relics - suggesting William took a rather cynical approach to mystical topics) to bolster his claim. And he attacked when he did because the wind had been against him previously. (It had been against him for so long that Harald Hardrada and Tostig Godwinson had invaded in the North of England, and been defeated, while William waited. Not sure where astrology comes into this. AlexTiefling (talk) 06:37, 23 October 2012 (UTC)

He might have invaded anyways, but 1066 saw Halley's Comet extremely bright, and it was certainly interpreted as a sign (in favor of William and against Harold) after the fact. It does feature prominently of the Bayeux Tapestry. See Halley's Comet#1066. Also see Post hoc, ergo propter hoc ;-) --Stephan Schulz (talk) 18:51, 23 October 2012 (UTC)

Not quite in the "President orders China to be bombed" league, but see Nancy Reagan#Influence in the White House. -- Jack of Oz ^[Talk] 08:53, 23 October 2012 (UTC)

@242.9: I think you misread or misunderstood part of my comment. I did not mean to imply that philosophers or humanists believe things because they make one feel good. I said "Science is not the only valid way of obtaining insight into the human condition", and I stand by that claim. I should not have tried to speak for e.g. humanists or philosophers, so I will just speak for my self: I believe that we can obtain insight into the human condition through e.g. art. Lastly, I apologize for my poor wording. I mean "humanist" in the sense of "a professional practitioner in the humanities," (see [32]) and not secular humanism, or any other type of humanism. SemanticMantis (talk) 14:05, 23 October 2012 (UTC)

I can think of at least one astrology thing that wasn't related to ancient gods - [33] (perhaps the second most unlikely Nature paper, which I'd rank just ahead of Duesberg's commentaries but not quite as unlikely as that one with the "patterned water") Wnt (talk) 04:17, 23 October 2012 (UTC)

Didn't Hans Eysenck do a scientific study that demonstrated correlations of personality type to birth sign (though not predictions)? -- Q Chris (talk) 08:46, 23 October 2012 (UTC)

Michel Gauquelin. -- Jack of Oz ^[Talk] 08:53, 23 October 2012 (UTC)

The astrologer Michel Gauquelin did. A repeat of the test, by independent scientists showed no such correlation, though Gauquelin did try and pressurize them to add and remove people in the sample. IRWolfie- (talk) 09:10, 24 October 2012 (UTC)

He finished up killing himself. -- Jack of Oz ^[Talk] 22:20, 24 October 2012 (UTC)

Your page http://en.wikipedia.org/wiki/Life is lacking a critical characteristic of "Life" in the 'Definition Section"

Dear Sir:

your definitions of "Life" is lacking a critical characteristic of "Life" in the 'Definition" section. All life must have a set of instructions inherently as a part of its existence, called its "Genome". The web page, http://www.genomenewsnetwork.org/resources/whats_a_genome/Chp1_1_1.shtml of the Genome News Network will help you clarify the issue.

Of the seven characteristics given for life none are more important than the fact that some form of instructions for its making must be inherent in it. Without this it cannot become alive.

Also, I don't believe that your sentence "Life is considered a characteristic of organisms that exhibit all or most of the following:[25][27]" in the article is accurate. Yes, life is a characteristic of "being alive" but it is not necessarily a characteristic of an organism because a dead organism is an organism that does not have life. Froibleonline (talk) 22:36, 22 October 2012 (UTC)

Proposed amendments to individual pages should be raised on their talk pages. Talk:Life is the page you want. We do already have an article on genome, as well as many thousands of editors who know a great deal about genomes. And while I'm not one of those users, it occurs to me that it is not a foregone conclusion that a thing must have a genome in order to be considered alive. As for the Genome News Network, you may wish to read our policy on reliable sources. AlexTiefling (talk) 22:41, 22 October 2012 (UTC)

PS: You don't need to address us as 'dear sir'. Not all of us are male, but all of us are ordinary users like you. This is the encyclopedia anyone can edit, and so all the editors are also the ordinary readers. AlexTiefling (talk) 22:42, 22 October 2012 (UTC)

"...not all of us are male...": on the Science desk? Amongst the people likely to respond to this question, everybody probably is male. --140.180.242.9 (talk) 04:48, 23 October 2012 (UTC)

User:TammyMoet and User:Medeis, among others, would probably disagree with that remark. Then there are anonymous IPs, of whom we know nothing. -- Jack of Oz ^[Talk] 08:41, 23 October 2012 (UTC)

Why keep a dog and bark yourself? ;) --TammyMoet (talk) 09:54, 23 October 2012 (UTC)

Telecommunications energy use

Hello Wikipedia. How much energy does the world's telecommunications infrastructure (particularly the World Wide Web including all computers and servers) consumes in one day? Thank you!--Colonel House (talk) 22:50, 22 October 2012 (UTC)

Typing "internet energy consumption" into Google got me this as the first result. --Jayron32 23:00, 22 October 2012 (UTC)

So its 2% of all electricity produced globally. Thank you!--Colonel House (talk) 23:13, 22 October 2012 (UTC)

Of course, that number supposes that all 500000 data centers consume 10MW. Given that it's a clean energy site, I suspect 10MW is a high-end outlier and that the true average is much lower. — Lomn 23:26, 22 October 2012 (UTC)

The U.S. Department of Energy's Energy Information Agency tends to provide more authoritative information than Google for these sorts of questions. I directly navigated to their website and found a breakdown of commercial electricity in the United States. If that brief overview doesn't sate your demand for statistics, large quantities of annual statistics are also made available. It is also worth reading How can we compare or add up our energy consumption? This document will help you make meaningful sense out of the large number of different types of statistics with respect to electricity, and energy in general.

Consider these statistics ranking economic sectors by energy-intensiveness: the four largest sectors are petroleum refining, chemical processing, forestry, and steel production. These dwarf the telecommunications industry in terms of total electricity and energy use. In fact, in the Annual Energy Outlook - which, at over 250 pages, is about as thorough a data-analysis report on energy consumption as you can get - telecommunications is so irrelevant that it only appears as a few footnotes on statistics for electricity consumption: an aggregate statistic of "Total energy consumption by end use" for commercial and industrial sectors provides one line-item, which "includes miscellaneous uses, such as service station equipment, automated teller machines, telecommunications equipment, and medical equipment." That entire "Other Uses" category constitutes just about 5% of total commercial energy consumption. Nimur (talk) 00:55, 23 October 2012 (UTC)

Unfertilized bird eggs

Farm chickens lay unfertilized eggs. That is the extent of my knowledge on the subject. But do other birds routinely lay unfertilized eggs? If so, do they treat the unfertilized eggs differently? Do they know which eggs have not been fertilized and kick them out of the nest? Thanks. Someguy1221 (talk) 22:54, 22 October 2012 (UTC)

Sure, most (all?) birds will lay some unfertilized eggs. Basically, this is just saying that no fertilization process is 100% successful. Human breeders commonly candle eggs to identify and remove infertile ones. In agricultural chickens, the eggs are infertile because the hens don't have access to mates. In the wild, birds might not reject unviable eggs until they rot, but unfertilized eggs are usually eventually rejected if the parent is brooding viable eggs. That being said, I think that frequent egg laying without insemination might be a highly derived trait only present in domestic fowl. That is, I suspect most wild species would not lay eggs unless they have been inseminated, and have a decent chance of producing viable eggs. SemanticMantis (talk) 23:39, 22 October 2012 (UTC)

If you keep a female of any species of parrot as a pet, the chances are that she will occasionally lay an infertile egg when springtime comes around. They tend to sit on it as if it was a fertile egg. The advice I've always heard is to leave her to it until she comes to the realization that it's not going to hatch and abandons it of her own volition. Otherwise she might lay more eggs, which isn't good for her. Also, a mated pair of Budgerigars, in my experience with them, will sometimes produce an entire clutch of 5/6 eggs that never hatch, perhaps because they were never fertilized in the first place (though there could be other reasons). Or only one egg will develop and hatch. I think that there's an element of hit and miss about it. --Kurt Shaped Box (talk) 23:57, 22 October 2012 (UTC)

Be aware that farm chickens will also lay fertilised eggs if they happen to have a rooster handy. That means that those free range eggs you can pick up at the farm gate may well be fertilised. HiLo48 (talk) 07:33, 23 October 2012 (UTC)

Yep, it's not an urban legend that people sometimes crack open a free range egg and find a half-finished foetus inside. Happened to my grandmother about ten years ago with some eggs that had come directly from a local farm. --Kurt Shaped Box (talk) 22:01, 23 October 2012 (UTC)

Yes, and in some places/times, this is a feature, not a bug ( at least for duck eggs ;) See Balut_(egg). SemanticMantis (talk) 00:20, 24 October 2012 (UTC)

October 23

Skunk-epoxy smell?

After using epoxy glue, I put the unused residue in a garbage can. Returning home hours later, I thought I smelled fresh skunk odor; then realized I was smelling the epoxy.

Is there a chemical similarity that would explain this or is it just a peculiarity of my nose? Thanks, Wanderer57 (talk) 02:32, 23 October 2012 (UTC)

Common chemicals that are easy to abuse as inhalants, such as some glues, often have Denatonium added. It is a bitterant, designed to make a product taste or smell unpleasant. I've never noticed a skunk smell from a product with a bitterant, but perhaps there are other bitterants that develop that smell. According to our article on skunks, the scent is pretty complicated - perhaps you're noticing something in the epoxy that is close to one of the components of skunk spray, and without more context skunk became the closest match. 209.131.76.183 (talk) 14:00, 23 October 2012 (UTC)

Also note that there is considerable variability in how people perceive smells. Here are two differences:

1) Different people can detect different smells, with the odor asparagus produces in the urine being one example. Some people smell it, some don't. In your case, perhaps you are able to smell a common skunk/epoxy component, while others can not.

2) How our brain distinguishes and categorizes smells is different. So, some people might think that two similar chemical compounds smell the same, while other people do not. StuRat (talk) 14:10, 23 October 2012 (UTC)

Growth over a sliver

First and most important: this is NOT a medical question! So, here goes. A few months ago while unloading some wood from my truck, I go a sliver in my finger. I was able to pull most of it out but some remained and I was unable to get it all out. So, I just kept the area clean and didn't bother getting medical attention since it wasn't bothering me and there was no infection. So, at present, where the sliver remained it appears that my body has grown around the sliver and there is now something like a callous there. It is not bothering me nor does it impair any functioning but I am wondering about what happened from a biological perspective. What is the growth around the sliver? 99.250.103.117 (talk) 04:50, 23 October 2012 (UTC)

There are two possibilities:

1) Scar tissue, which is white and hairless.

2) Normal tissue, which looks, well, normal.

I got a splinter some 30 years ago, which was a piece of stained wood. I got out most of it, but the chunk buried deep under the skin remained there. Normal skin grew over it, and, in time, the wood dissolved, leaving only the stain. So, I gave myself a tattoo the hard way (not that the normal way is particularly easy). StuRat (talk) 05:05, 23 October 2012 (UTC)

There are others too I think? Hyperkeratosis? Callus? --BozMo talk 08:54, 23 October 2012 (UTC)

I am going to go with the scar tissue option! Thanks. 99.250.103.117 (talk) 19:30, 23 October 2012 (UTC)

Launching atomic weapons

Can atomic ballistic missile or group of them be launched by whatever unit is at charge? If they need a password from the president, then they can be disable by just attacking him, but otherwise, how to avoid a mad commander from launching them? Comploose (talk) 11:56, 23 October 2012 (UTC)

You may find the two man rule article worth reading. Richard Avery (talk) 12:10, 23 October 2012 (UTC)

While not cases of launching via the local commander, see also the cases of Vasili Arkhipov (who, as second-in-command, persuaded his CO not to launch a nuclear torpedo during the Cuban Missile Crisis), Stanislav Petrov (who correctly diagnosed a false alarm rather than passing a report of an American nuclear strike up his chain of command), and Dead Hand (a possibly-automatic Russian nuclear retaliatory system which may remain operational). There is also the case of Harold Hering, who was discharged from the US Air Force after asking, "How can I know that an order I receive to launch my missiles came from a sane president?" — Lomn 13:20, 23 October 2012 (UTC)

But, what if the Russian had attacked the US and destroyed the congress and White House? Would a nuclear submarine with a two man rule be able to decide on their own to retaliate? My knowledge is entirely derived from Hollywood films in this matter. I suppose they are not reliable sources, even if the question provides grounds for a thriller. Comploose (talk) 13:23, 23 October 2012 (UTC)

Modern nuclear weapons in the US arsenal are protected by Permissive Action Links. You need authentication codes to activate the warheads; if you don't have the codes, the nukes won't work. These are transmitted only on order from the President or someone else in the line of succession (including the designated survivor in extreme circumstances). The codes (the so-called nuclear football) are kept near the President at all times. There are at least two other "footballs" in case one is destroyed somehow. I suspect there are fallback plans for all footballs being destroyed or inactive, but they likely do not involve allowing field commanders to make those decisions. There have been, in the past, procedures for "predelegation" of nuclear authority, where the President says, "I give you, the field commander, the authority to do this if you need to or if you think everyone over here is dead."[34] I've no clue if those are still on the books but I wouldn't be super surprised if they were available in some form.

What really prevents rogue commanders a la Strangelove is a fairly intense system of surveillance, psychological profiling, and lots of overlapping authority. You can't get within 1000 feet of a live nuclear weapon without them knowing a lot about your life, including your bank records, and your current mental and physical health. There is no doctor-patient privacy in the nuclear triad. I've met at least one nuclear missile base commander over the years, and they are a tightly-wound, carefully-chosen bunch. (This in no way guarantees that everything is always functioning correctly, of course. There have been enough errors and accidents — even very recent ones — to make one quite disturbed. It only takes one big one for a lot of people to die...) --Mr.98 (talk) 13:48, 23 October 2012 (UTC)

In Britain we have a system of Letters of last resort. These are letters written by the Prime Minister immediately after taking office, and describe actions which may be taken by nuclear submarine captains in the event of destruction of British society (or, at least, the Prime Minister and another designated person who is authorised to take over from the PM in the event of his death). The contents of the letters are highly secret, but it is believed that they lay out a number of options to the captain, including turning the submarine over to US command, heading for Australia, or launching a nuclear missile. The circumstances under which a captain is authorised to open the letter are also secret, although it's believed that one criteria is being unable to receive Radio 4's Today program for a specified number of consecutive days - the theory being that if John Humphrys has gone off the air then British society has obviously come crashing down. If this seems a little amateurish, consider also that, in the 60s, with the Cold War in full swing, the Prime Minister wanted a radio fitted to his car in order to keep him in touch with GCHQ should it become necessary for him to authorise military action whilst on the road. It was decided that this would be too expensive, and so instead they agreed to use the AA's radio network. In an emergency, the AA would be sent a coded message, and would call on one of their patrolmen to flag down the prime-ministerial car. The PM would then get himself to the nearest public phone box and call central command. A supply of small change was kept in the car for this purpose. - Cucumber Mike (talk) 13:55, 23 October 2012 (UTC)

It's possible that American submarines have something similar, though I've never heard of it being the case. Our article on PALs though says that the UK doesn't use them, so it's not like that secret letter has to contain authorization codes. There are no UK authorization codes. Kind of disturbing. --Mr.98 (talk) 14:10, 23 October 2012 (UTC)

Although, at least in the early days, the code for the Nuclear football was 0000, hardly the most secure code in the world. The PAL article says that the UK used to have physical locks on their airborne nuclear missiles derived from bicycle locks. Nowadays, though, I think I'm right in saying that the only nuclear weapons we control ourselves (as opposed to American missiles that may or may not be based on British soil) are the submarine-based Trident missiles. These do have codes, at least according to this Daily Mail article. - Cucumber Mike (talk) 14:32, 23 October 2012 (UTC)

Aha, here we go. Nuclear weapons and the United Kingdom#Nuclear Weapons Control: "Currently, British Trident commanders are able to launch their missiles without authorisation, whereas their American colleagues cannot." See also, in the same article, the procedure under which a submarine commander may appeal to the Queen should he mistrust the orders he is given - presumably this option isn't open to their American counterparts. - Cucumber Mike (talk) 15:00, 23 October 2012 (UTC)

Cancer: cause and lack of cause

If a smoker gets lungs cancer people will say it's because he smoked. In cases where it's not evident, like children, people say that it's something that sometimes happen, in the sense that it's spontaneous there is no concrete explanation. But couldn't the first case also be spontaneous sometimes? Comploose (talk) 12:04, 23 October 2012 (UTC)

Yes, it could possibly be a 'spontaneous' cancer in a smoker, by spontaneous I assume you mean causes other than tobacco smoke. The real difficulty is how would we know whether the cancer is smoke related or caused by the several other causes this site explains, ranging from secondhand smoke to radon within the home. Richard Avery (talk) 12:25, 23 October 2012 (UTC)

It is important to recognise the difference between root causes (http://en.wikipedia.org/wiki/Root_cause) and triggers. Smoking is never a root cause of cancer, it is a trigger or possibly an accelerant. The root cause in lung cancer and almost all forms of cancer is genetic faults. An analogy is the failure of a lawnmower engine with dirt in the fuel. The dirt is the trigger of failure to run when it gets in the carburettor. But what is the root cause? If the owner correctly maintained the lawnmower, replacing any parts as appropriate, taking care with re-fueling, using a fuel strainer when re-fueling, the dirt wouldn't get in. However, if there is no dirt, the mower would run regardless. Hence dirt is the trigger, and not using a fuel strainer the root cause. Once you have cancer, it is possible to identify the root cause, and the most probable trigger, but with lung cancer they usually don't bother as the treatment will be the same in any case. Wickwack 124.178.178.65 (talk) 13:17, 23 October 2012 (UTC)

Cancer is a hard thing to pin down causally in individuals. Its onset is fundamentally probabilistic — you have many trillion cells, and whether one of them becomes cancerous in a dangerous way that the body doesn't detect and fix is largely a matter of chance. Your cancer risk — the chance of that happening — is definitely affected by both environmental sources (smoking, radioactivity, chemicals, etc.) as well as genetics (lingering bad codes in your genes). In an individual, you can never really tell what caused a given cancer — there are so many possible sources in modern life, including some that you can't predict for at all (e.g. a high energy cosmic ray happens to strike the wrong cell in the wrong place). What you can say is, over a given population, X number who are exposed to a particular environmental source (e.g. smoking) will develop cancers. In this way you can quantify these cancer risks and say things like, "smoking increases your cancer risk by X% over the baseline," and "radon gas in your basement increases your cancer risk by another X%" and so on. There are also cancers which are associated, statistically, with particular environmental exposures, which makes a more plausible argument — lung cancer for smoking, for example, but also bone and stomach cancers for certain types of radiation exposures, and so on. They aren't, though, complete smoking guns; it's still a statistical, population-based argument that is being collapsed to a "what is most likely" the cause of a specific cancer in a specific individual.

This isn't to say that the cancers don't have causes. All cancers have "causes" — we just don't have any way of knowing what they are, except probabilistically. The most spontaneous-looking "cause" is genetics, though ironically that's probably the easiest one to pin down (or will be, in the near future), since we can actually screen for many known cancer genes. The truly "spontaneous" ones, like exposure to cosmic rays or natural radioactivity, are very hard to isolate from the other many possible environmental causes. (Note that even more complicating is that these risk factors can interact; radon gas exposure, by itself, does not raise your risk level very much. If you smoke cigarettes around radon gas, though, your risk factor shoots up, because the radon daughter decay products hitch-hike on the cigarette byproducts and do a lot more damage than either the smoking or the radon would do on its own.)

Wrapping one's head around probabilistic risks is not intuitive and unsurprisingly a lot of people either revert to simple statements like "X causes cancer," which can get misleading because we all know people who are exceptions to that rule and this in turn causes a lot of people to reject these statements ("my grandmother smoked until she was 89 and she was fine, so how bad could it be?"). This is a major difficulty in the public health and risk communication worlds.--Mr.98 (talk) 14:04, 23 October 2012 (UTC)

Mr 98 is dead right about it not being intuitive and it being difficult to understand, but appears to have missed the point about root causes vs triggers. Neither smoking nor radon gas nor cosmic rays are root causes. They are triggers. Consider: Can a person who has no genetic faults get cancer, even if they smoke, inhale reasonable (& even some unreasonable) quantities of radon gas, or have a natural cosmic ray inundation get cancer? The answer is no. Can a person who has a sufficient range of genetic faults, but no exposure to smoke, radon, or cosmic rays get cancer? The answer is yes. If a person, who has developed cancer, has that cancer eliminated by medical treatment, and ceases exposure to trigger get cancer again? The answer is yes, and it occurs with significant probability. Note that noboby gets cancer with only a single bad cell and nobody gets cancer with only a single cancer-relevant genetic defect. To get cancer you must have a combination of genetic defects - a defect that allows the progeny of stem cells to keep on dividing, a defect that prevents appropriate adjacent cell-mediated cell death, and at least one genetic defect affecting the immume system response to tumours. This is why it has taken quite a while to figure the casues of cancer out. It used to be thought that ionising radiation causes cancer at rates that are a function of exposure, with the natural exposure responsible for the natural rate at which cancer occurs. In fact, a genetically sound person will not ever get cancer (certain unusual forms may be exceptions) unless subjected to extreme exposure. Trouble is, probably 25% of the population has some genetic defects. Cancer has only seemed to be probabilistic because we haven't understood it until very recently.

The fact that root causes vs triggers has not been understood by public health educators and communicated to the public is why you get "My grandmother smoked like a chimney and lived to 89, so it can't be smoking". However, if the public becaomes too scared to smoke, that's a good thing in multiple ways. Wickwack 124.178.178.65 (talk) 15:18, 23 October 2012 (UTC)

Wickwack, what you say is at least scientifically unsound, but I would rather tend to call it incorrect. There is no such thing as a "genetic defect". Every human has a genome consisting of thousands of different alleles (and a "healthy genome" doesn't make sense as a scientific concept), and every second, mutations happen in some cells of the body. If you talk about cancer, there is no such thing as "a person's genome", it's all a boiling ocean of mutations and selection/counterselection inside of the body. If you irradiate a tissue (or expose it to certain chemicals), you increase its mutation rate, which can increase the probability that exactly the right combinations of mutations meet inside a single cell to become the phenomenon we call cancer. While your assessment of the needed mutations is a nice list, it is oversimplified, as is the linear development of tumors. There are very many pre-malignant lesions in each healthy human, at every moment. Your distinction of "root causes" and "triggers" is artificial. Cancer works the way it works because of the physical laws that govern our cells. It's like answering the (philosophical) question "what came first, the hen or the egg?". Cancer is a logical consequence of how our body and genome work, in every one of us. Btw: The reason why people that got a cancer treatment are at a higher risk for "getting cancer again" is not the genome they received from their parents (for most people without defects in DNA repair), but is a consequence of "cancer cells" left over after treatment, that linger on and sometimes grow out again. Even the treatment can't negate the stochastical nature of cancer, so you normally can't kill every mutated cell (or the pre-malignant cell clones that might still be around, somewhere).

So, to summarize: Cancer might be a hard topic, but please don't simplify to such a degree that you are making claims that are not backed up by reality (where do the 25% even come from?!?). --TheMaster17 (talk) 16:03, 23 October 2012 (UTC)

I think that this "root causes" and "triggers" issue may muddy the waters. The "root cause" of cancer, if you will, is that humans are designed wrong - there are events that can occur with low frequency in anyone to cause the disease; given long enough they will. But the fact that some circumstances increase this risk doesn't seem to make them less important, to me.

The biological concepts are that there are tumor initiators and tumor promoters, which work a bit differently. A tumor initiator is something (UV, radiation, chemicals) that directly increases mutation - i.e. a mutagen. (As an aside, I would think "epigenetic tumor initiators" would be possible, but the phrase is unknown to Google, and I didn't find anything on it in a very quick search. DNA demethylation is supposed to contribute, but actually zebularine (a DNMT inhibitor) fails to deliver and actually protected against tumors in one test. [35] Nonetheless the existence of normal mice produced from teratocarcinoma cells proves that, in theory, a tumor can form by more or less entirely epigenetic mechanisms, and I didn't look long or hard enough to know that a proper search wouldn't find something) Anyway, a tumor promoter works to increase the propagation of cells with the initial mutation, so that they can eventually accumulate a bunch of mutations that lets them grow to large size and ignore signals to die, i.e. become fully transformed. (Sorry - I cannot believe what a sorry state these three articles on cancer are in, considering the importance of the concepts) Wnt (talk) 17:49, 23 October 2012 (UTC)

Yes, I (Wickwack) presented a very simplified view. I was well aware of that when I posted. To describe cancer accurately would probably take millions of words. And not be entirely possible, because not all the details are yet known. I also chose to use lay terms such as "adjacent cell-mediated cell death" rather than the correct term cell mediated apoptosis (programmed cell death). Wnt and TheMaster are not wrong entirely, but are presenting a picture that needs revising in light of facts uncovered by research only recently. One should always be carefull not to keep on repeating an older picture that is not wrong exactly, but has been revised by recent discoveries. It's a bit like our undersanding of the atom. Early on scientists developed a model comprising a nuecleus surrounded by orbiting particle electrons in "shells". It's now known that this isn't right, but it still does explain certain things in physics and chemistry just as well as it always did.

To cite a cancer example to explain the root cause/trigger model, it was discovered about 18 years ago that most women who develop the most common forms of breast cancer have a certain genetic defect, which they named BCRA-1, BReast CAncer gene 1, because they were breast cancer reseasrcher investigating breast cancer. It was later shown that this defect, which is inherited from a parent, not a spontaneous mutation, compromises DNA repair, and it is involved in many types of cancer, not just breast cancer. So the name is misleading, but it's the name that is in use. BCRA-1 is a root cause, because if a woman, or man, doesn't have it, their chances of getting breast and certain other types of cancer is signifcantly reduced. It is not reduced to zero, not merely because of a "boiling ocean of mutations and selection/counterselection inside of the body", but because there are other root cause genetic defects possible.

Yes, the body does have DNA damage and mutations happening all the time. Yes, the design isn't perfect - in a sense we are designed wrong. But, as we are an evolved system, our ancestors have long evolved built-in means of recognising and dealing with potential and actual cancer. It's when these evolved mechanisms themselves acquire inheritable defects that cancer becomes the huge problem that it is. Back to BCRA-1 (and the subsequently discovered BCRA-2), it was very sad that when a test become available for this genetic defect that some women had the test, tested positive, and had their breasts pre-emptively removed. Why? If the only genetic defects you have are BCRA-1 and BCRA-2, you can't get breast cancer. And if you DO have BCRA-1 and BCRA-2 and a different set of other gene defects, you most likely will not get breast cancer, but you have a higher probability of getting some other sort of cancer somewhere else in the body (which my BCRA-1 positive wife in fact did).

Some inherited factors increase cancer susceptability but confer an advantage in other respects and can even be essential to life. This does not invalidate the root cause & trigger model. You can have an inherited propensity to overweight - this will make it easier for breast cancer to grow, but it is not the root cause. In a nomadic life the ability to put on weight when food is plenty may be an advantage.

Far from muddying the waters, looking at it from a root cause & trigger angle improves understanding, and explains why for example that although smoking and lung cancer is strongly linked, only some people who smoke get lung cancer.

Wickwack 124.178.55.56 (talk) 01:47, 24 October 2012 (UTC)

Wickwack, you are doing it again. BRCA-1 and BRCA-2 are not "defects" that you have or don't have, they are genes that every human on the planet has two copies of. Again, I can guess what you are alluding to: There are certain variants of BRCA-1/2 (called alleles in genetics) that can raise the statistical risk for certain tumors (among them certain types of breast cancer). As it stands above, your statement is clearly wrong. Please, don't simplify concepts to such a degree that they become wrong. Also, talking about "design" in a biological context is very, very unscientific. There's nothing "wrong" with those people that develop cancer, and for sure there's nothing wrong with our genome. "Wrong" and "Right" don't exist as a biological concept. Organisms are the way they are because of evolution (which in itself is depending on the physical laws of our universe), no one designed them, and they are "perfect"(which is not a biological concept) in the sense that they out-competed their long gone ancestors and there's nothing better around. --TheMaster17 (talk) 09:09, 24 October 2012 (UTC)

Actually, the terms "wrong" and "design" were introduced by poster Wnt, not me. But he not wrong in using this terminology in teh sense that he was - he meant our "design" is not perfect because we do get cancer. Can't argue with that, but it is not the most useful concept. Wickwack 60.230.234.252 (talk) 11:32, 24 October 2012 (UTC)

Regarding The Master's statement "[th]e reason why people that got a cancer treatment are at a higher risk for "getting cancer again" ... is a consequence of "cancer cells" left over after treatment, that linger on and sometimes grow out again" is obviously true, and has been known for considerable time. But, again recent research, and experience of oncologists has shown that this is decidedly not the whole picture. 30 years ago, if you had got say, breast cancer (and was treated for it), then, years later, got cancer somewhere else, it would be assumed that it was a metastasis of the orginal cancer, and it didn't matter because the treatment was essentially the same (cut it out and use methrotrexate-style chemo) anyway. 20 years ago if you had got breast cancer in one breast (and was treated for it the usual way - lumpectomy or mastectomy, chemo, and radiotherapy) and years later had breast cancer in the other breast, it would be assumed that either it was a spread of the original cancer, or a similar type of cancer arising independently. But the tools are available today (microscopic analysis, marker detection, etc) that can show which it is, either a) that yes it is a separate tumour of the same type, or (b) it is a tumour of a quite different type. And the treatment will be adjusted accordingly. 30 years ago, if the first detected tumour was in(say) your brain, it would be assumed to be a brain tumour. But with today's tools, it may be determined that it is in fact a secondary (and often what type of primary must be the case) - and they'll go looking for the primary, which is presumably still there somewhere (sometimes it has disappeared) as it was not treated, so they can treat it appropriately. It is becomming clear that in quite a high percentage of cases, a second diagnosis of cancer is of a cancer quite unrelated (except thru a common genetic root cause) to the fist one diagnosed, i.e., is not something arising from cells left over after treatment of the first one. Incidentally, DNA repair is not the only built in feature that the body has for protecting itself from cancer, as I mentioned above. Wickwack 120.145.166.64 (talk) 03:30, 24 October 2012 (UTC)

I demand references for that statement. The most common case if you have a tumor relapse after treatment is a reoccurence of the same tumor (which, as you correctly state, is not hard to prove nowadays). There are some therapies that have some risk to induce a "new" secondary tumor by their own mutagenic effects, but those cases are becoming rarer and rarer (not more common as you seem to imply) because dosing is better than it was and those therapies are slowly replaced by better ones that don't have such strong mutagenic effects on non-tumor cells. --TheMaster17 (talk) 09:17, 24 October 2012 (UTC)

You did not read what I said. I did NOT say that treatment induced secondary tumours are more common now (neither did I say there has been an increase in treatment induced primary tumours) - I agree, refinement of treatment techniques (better radiotherapy machines and radiotherapy planning tools, better chemotherapy agents, and better adjuvant drugs) over the years has reduced such problems. What I DID say, if you go back and look, is that it is now being found (whith new diagnostic tools and with oncological experience) that more than one primary tumour type in the same patient is quite common. There's no reason to suugest they have become more common (except that longer lifespans increase the chances) - its a case of better tools bringing it to light. The occurance of treatment induced tumours is a separate issue. You implied that treatment induced cancers are always secondaries. I assume that you did not mean to imply that. In any case it is quite wrong. For instance, it has been well established for 20 years that certain adjuvant drugs for breast cancer increase the risk of uterine cancer - not a secondary breast cancer showing up in the uterus, but a new primary of different type. You might like to clarify which statement you want a reference for - I can then find one or more for you. Wickwack 60.230.234.252 (talk) 12:49, 24 October 2012 (UTC)

I agree, I meant "primary tumor" after a relapse, not secondary, which should be clear from the context. I would be interested in a reference to the "more than one primary tumour type in the same patient is quite common"-claim. If you mean by "common" "a freak chance of less than one in a million", then I agree. But for everything else I would want references. And just to clarify: We are speaking about tumors, about full-grown cancer. I'm aware that every living human has probably several sub-clinical mutated cell masses in his body, but they are not ordinarily regarded as "cancer", because they don't do any harm and are controlled by the immune system and cell intrinsic safety measures. Seeing a patient with two diffenrent cancer types at once is very, very, very rare according to medical literature; in fact so rare that it is hard to give reliable numbers for the chance, because most of these patients have pre-established conditions (defects in their DNA-repair, for example) that make the occurence of multiple tumors much more likely. --TheMaster17 (talk) 14:36, 24 October 2012 (UTC)

By "common", I certainly do NOT mean a one-in-a million thing. It's early days yet, but as until recently not only were the tools not available, the treatment would not have changed. Doctors are taught to not order a test if it won't change treatment. However we have now entered an era where the result will mean tayloring the treatment to suit. The incidence of tumours of differing type seems to occur in about 1 in 10 cases involving multiple tumours of common types, but it could be signifanctly less; it could be more. I will provide refrences when I get time. Do you have references to support your claim that muliple types in teh one patient is rare?

I agree that it is not useful to call "cancer" some wonky cell somewhere in the body. But your term "full blown" is no good either - do you mean diagnosed malignant? Or metastased all over the place and about to finish the patient off? By "cancer", "tumour", I meant a tumour that is detectable, either by the patient noticing a lump or symptom, or by imaging and pathology methods now commonly in use in Western countries. As you may know, cancer is discussed by medical people in terms of staging. Stage 1 is a tumour in situ and not detectable in lymph nodes, Stage 2 is detectable in lymph nodes, up to Stage 5 - make peace with Aunt Frizzie while you still can. Generally tumours should these days in Western conutries be diagnosed at Stage 1 or perhaps Stage 2 and are assumed that they will progress to Stage 5 if treatment is not done. So, in the above posts, I effectively meant Stage 1.

Wickwack 60.230.234.252 (talk) 15:43, 24 October 2012 (UTC)

The root cause and trigger way of looking at cancer is of benefit because it doesn't just help explain why you shouldn't smoke (smoking being a trigger) even though we all know multiple people who have smoked all their adult lives without getting lung cancer, it explains why, if you have a parent that developed lung cancer, you definitely shouldn't smoke, even if that parent never smoked (you may have inherited some duff genes - the root cause, and the parent had a different trigger). Root cause analysis and its terminology originates in engineering. It is not (yet) well established in the medical field becasue it has not in the past seemed usefull. It does not mean taking it to rediculous and not usefull lengths. One would not usefully suggest that the root cause of cancer is our evolutionary path - as Wnt pointed out. An analogy is the motor car. Cars sometimes breakdown, but very seldom if they are maintained and serviced according to manufacturer's guidelines. You could say the root cause of a breakdown is the evolution/refinement path of vehicle design since manufacturing started. But that would not be terribly usefull. If however, you investigated a series of breakdowns and found that a dealer was not servicing customer's cars correctly - that would be a root cause, and very useful action could be taken on that basis. Noting that some customers had more breakdowns because they drove their cars hard could also be usefull, but not as usefull as finding the root cause. — Preceding unsigned comment added by 60.230.234.252 (talk) 13:19, 24 October 2012 (UTC)

What exactly does "is not (yet) well established in the medical field" mean? The more I read this, I have the impression you are making this "root cause" thing concerning cancer up. I never heard about such a distinction, and in my opinion it is not even logical. A cause is a cause. I can't see any fundamental difference between those things you call "trigger" and those things you call "root cause", perhaps only that you believe your triggers are more immediate in effect, while "root causes" are somehow inherent in the person/thing itself. This distinction is not really useful or helpful to understand cancer. And what Wnt pointed out was very much correct: One of the causes of cancer is on a fundamental level the way our body and cells are organised, which is rooted in our evolutionary path. Creatures with different evolutionary pathes get different cancers, and some can't even get cancer at all (think about single celled liveforms). The analogy with the car is wrong at so many levels, I don't even know where to start. Again, please don't simplify things till they are wrong. I suggest that if you want to discuss this further, let's move to my talk page (as you use dynamic IPs and are not logged in, your talk page wouldn't be that useful) to not clutter the reference desk any more. --TheMaster17 (talk) 14:51, 24 October 2012 (UTC)

Oils aint oils; Causes aint causes. I would have thought this obvious. I'll try a different analogy: It happens that I have a problem with nuts. If I eat nuts, I'll cough a lot and make wheezing noises. What is the cause of the wheezing and coughing? You could say it is the nuts. You could say it is just tough luck - what I ended up with after x many millions of years of evolution. Or you could say the root cause is the particular gene variation I have - it's a gene variant (root cause) that makes me sensitive to nuts (the trigger). I don't know if that gene has some advantage, as far as I know nobody does. But it matters not. At the moment it matters not much to me what terminology is used, but it might at some future time if they invent a suitable gene therapy. And it's good to know that I can pass this root cause on to offspring. The terminology suggests latent causes versus immediacy, but that is not the core concept. Most triggers in cancer are not at all immediate in effect - smoking and asbestos fibres are obviously far from immediate, typically needing 40 years + to get to Stage 1 cancer. However, most, but not all, root causes are inherited. Wickwack 60.230.234.252 (talk) 16:02, 24 October 2012 (UTC)

Two-pack-a-day smokers are 28 times as likely to get lung cancer as the general population. So take your population of such smokers who have lung cancer, maybe 3.6% would have gotten lung cancer anyway. (Source: Weinberg's Biology of cancer). Someguy1221 (talk) 18:00, 23 October 2012 (UTC)

Have you correctly understood the reference? That figure (28 x ~ 30 x) is commonly quoted and is derived from comparing recent cancer rates with the reported rate before smoking became widespread. But it is known that cancer was under-reported in earlier times, and there may be other modern era causes, such as increased lifespan and increased body weight. About 10% of lung cancers diganosed occur in non-smokers (well, they said they were non-smokers anyway). Wickwack 124.178.55.56 (talk) 02:05, 24 October 2012 (UTC)

The reference I used was a textbook which did not give the study's methodology. I'll have to check that then. Someguy1221 (talk) 09:20, 24 October 2012 (UTC)

Just to at least try to give a referenced answer to the OPs question: Our article cancer is quite good, and has an elaborate section about causes. --TheMaster17 (talk) 15:10, 24 October 2012 (UTC)

• I think part of the controversy of this section is the classic false Nature versus nurture dichotomy: Is cancer "caused" by one's nature (genetics) or "caused" by one's nurture (environment). The answer, as with nearly every one of these false dichotomies, is that cancer is caused by the intersection of nature and nurture. That is, it is usually not sufficient to have one and not the other: A person who has the correct genes to get a specific certain cancer may never get it if they are not exposed to the correct environmental triggers, while a person who smokes two packs a day for 30 years may never get lung cancer if they aren't predisposed to it. It also isn't as simple as pure cause-and-effect: there's likely some dumb luck involved as well: it's a percentage and probability thing, not a "action and reaction" thing. --Jayron32 18:36, 24 October 2012 (UTC)

I would like to add that there's (biologically) no difference between "having the right genes" and "having the right environmental conditions" (as Jayron alluded to with the false dichotomy). In the end, all that is important is that certain gene variants come together in the same cell. Whether some of them come from your parents (in the form of genes that you inherit) or from physical/chemical effects that changed the DNA of the cell after conception, doesn't matter from the tumor's perspective. It all boils down to stochastical chances for this to occur. Sure, if you bring half of the genetic changes in the DNA of your whole body with you from the start, the chances are surely higher to develop cancer, but it's still only a chance. On the other hand, even if we imagine that there might be humans that are highly resistant to cancer (because their parents gave them just the right mix of gene variants), nothing stops the first hundred cosmic rays that strike their body to change just the right pieces of DNA in just the right cells for a cancer to occur. It's just very, very unlikely. It might be that we can give better numbers to those chances in the future, but they would still only be chances on a population level. It's like a lottery: Although the chances to win are really slim, there are winners every week. --TheMaster17 (talk) 09:02, 25 October 2012 (UTC)

zodiac articles

I'm wondering what happened to the zodiac article dealing with different astrology signs it used to be Each sine had its own page, giving it a detailed description and interpretation. Now when you click on a month it just goes to a catch all page which doesn't explain much what happened to the individual pages?--Wrk678 (talk) 12:40, 23 October 2012 (UTC)

As an astronomical feature, each constellation has an article, i.e. Aries (constellation). I'm surprised that all the articles on the individual zodiac signs have been made into redirects. Perhaps ask Wikipedia:WikiProject Astrology what's gone on there? LukeSurl ^{t c} 13:09, 23 October 2012 (UTC)

Hmm. Yesterday User:Dominus Vobisdu went and changed all the sign articles to redirects. I don't know if this was unilateral or followed a discussion. LukeSurl ^{t c} 13:13, 23 October 2012 (UTC)

The same user has, over the past few weeks, deleted or made substantial cuts to all of the Chinese zodiac signs, and if you go back further other astrology-related and similar articles.    → Michael J Ⓣ Ⓒ Ⓜ 14:16, 23 October 2012 (UTC)

If this is all unilateral, he should be reverted. Sure astrology isn't valid science, but it still merits substantial articles, due to it's cultural impact. StuRat (talk) 14:18, 23 October 2012 (UTC)

If there were anything approaching reliable sources which discussed the cultural impact of zodiacal signs, you'd have a point. As it stands, all there seems to be on the subject is vague and contradictory waffle from astrologers who clearly can't agree anything amongst themselves - and don't actually want to, as it would cut the market for further contradictory waffle. AndyTheGrump (talk) 14:26, 23 October 2012 (UTC)

You seem to be confusing the validity with the cultural impact. Finding reliable sources that show the cultural impact should be simple enough, say a poll of the percentage of people who believe in, and alter their behavior due to, their horoscopes. I believe Nancy Reagan was one. From our article: "...more controversy ensued when it was revealed in 1988 that she had consulted an astrologer to assist in planning the president's schedule after the 1981 assassination attempt on her husband. " StuRat (talk) 14:33, 23 October 2012 (UTC)

You seem to be confusing the cultural impact of astrology with the cultural impact of individual zodiacal signs. AndyTheGrump (talk) 14:33, 23 October 2012 (UTC)

As StuRat says, we should have articles on these as cultural phenomena. Even if they were crappy, having no articles to improve seems worse. Currently Wikipedia has no information on what pseudo-guff is associated with which sign. These things have a wide enough cultural footprint to be of encyclopaedic impact. LukeSurl ^{t c} 14:36, 23 October 2012 (UTC)

The astrologers can't agree on the pseudo-giff though - they all say different things. Which makes assessing the cultural impact of an individual sign rather difficult... AndyTheGrump (talk) 14:40, 23 October 2012 (UTC)

True, but even in difficult cases we still have articles. Generally speaking we can't just have 12 articles effectively deleted unilaterally, this sort of action requires a community discussion. LukeSurl ^{t c} 14:50, 23 October 2012 (UTC)

(EC) This discussion would best be held elsewhere. But anyway it seems to me that point of whether those articles should exist is largely moot. The content which was deleted seems to be the sort of stuff which should be covered in the redirect article and largely is. In the event of a dispute over the existence of the articles, the best way to handle that would be to find and add enough reliably sourced info to justify stand alone articles rather then argue a hypothetical of what could be in those articles. Remember the articles weren't deleted so all content remains in the history and you're free to reverse the redirect particularly if you add enough info to justify their being an article. Nil Einne (talk) 14:56, 23 October 2012 (UTC)

Wouldn't it be best to ask Dominus Vobisdu whether this was an unilateral deletion first? AndyTheGrump (talk) 14:57, 23 October 2012 (UTC)

I've slightly modified my response above but one key point was there from the start. As I said, there was no deletion. Therefrore such a question wouldn't make sense. Nil Einne (talk) 14:59, 23 October 2012 (UTC)

OK, I've restored them to how they were prior to redirection, and suggest we hold a centralised discussion on Talk:Astrological_sign#Redirection_of_Western_Zodiac_signs. LukeSurl ^{t c} 15:14, 23 October 2012 (UTC)

We shouldn't dismiss astrology entirely without thinking about it. Sure, it's based on absurd theories, but suppose, say, the women in some village got a hankering for tea made with fresh veratrum flowers. (Hippocrates was a great believer in the stuff, but I think he administered it all times of year) Well, because of the critical periods of development, there might be one or two Zodiacal signs that specifically direct the birth of baby Cyclopes. Who knows - it is possible that somewhat less obvious characteristics have, at certain times and places, followed a rough astrological calendar in this way. Wnt (talk) 18:56, 23 October 2012 (UTC)

I would recommend reading up on what astrology is before commenting about how you personally find it plausible. You would need to show evidence for such a correlation of personality on the time of year. You would then need to show that this correlation corresponds in some way to the astrology divisions in sun sign astrology (which actual astrologers regard as inaccurate). Then you would need to explain why astrologers have failed every test to work out personality greater than that explained by chance alone. Then you need to explain why astrologers all make statements which all disagree with each other in the tests themselves; there is no consistency. Then you need to explain why you think the apparent position of a planet on the Celestial sphere, at your time of birth say, has an effect on you. Then you would need to explain why the angles the planets make with respect to each other, from the arbitrary position, matters. Then you would need to explain how your belief about the origins of astrology is consistent with the historical evidence for it's origins, such as with it's "modern" origins with the works of Ptolemy etc. Then you would need to explain why this correlation means we still shouldn't dismiss what astrologers do since they have failed every controlled trial of their abilities. You have your work cut out for you. IRWolfie- (talk) 22:24, 23 October 2012 (UTC)

It seems I misread, you weren't talking about personality but Cyclopes? What are you talking about and why would that influence whether we dismiss astrology or not as a hypothesis about the universe? What on earth do cyclopes have to do with astrology? You've constructed an absurd example, without evidence and assert that this somehow makes a concept, which doesn't mention cyclopes plausible to you? Whether some old villagers committed a post hoc ergo propter hoc style logical fallacy says nothing about whether astrology is correct or not. By the same logic maybe the anti-vaxers are right because someone got a jab and then got hit by a bus. IRWolfie- (talk) 22:39, 23 October 2012 (UTC)

There's some cases where the time of year that you are born can affect you, for example if your school system has a fixed date cut-off being older than most of your classmates throughout school is an advantage. Also I've read that late-stage foetuses of mothers who observe Ramadan, especially where the days are long, can be at a developmental disadvantage. [36] These can be explained by "terrestrial" phenomena however and not any action of the stars. LukeSurl ^{t c} 00:07, 24 October 2012 (UTC)

(I lifted those examples from Superfreakonomics by the way) --LukeSurl ^{t c} 00:11, 24 October 2012 (UTC)

In case I was unclear, I was not suggesting a belief in the system in its entirety - since so far as I understand no two astrologers really agree on everything, to suggest that seems excessive. The question rather is whether someone who didn't know any better, armed with a notion that astrology works, who makes ad hoc attempts to apply it to the local situation based on trial and error, might adapt the framework to make predictions that are correct more often than chance. And the answer still is probably not... but not impossible.

If I had to take a wild guess at something more plausible than Cyclopes, I'd suggest phytoestrogen mediated effects ... but those themselves aren't so clear to me. See [37] for the kind of thing I'm thinking of.

Keep in mind always that when we speak of the historical times when astrology evolved, life was very different. People couldn't buy raspberries any time of the year! Although some crops had the valuable ability to be stored for long periods, there were many things which were available only at one specific time. And different foods were eaten, sometimes by necessity, or at unlucky times nothing at all. So I'm thinking that the variation of pregnancies from different times of year would have been much greater than it is today. Wnt (talk) 06:43, 24 October 2012 (UTC)

So what if some coincidence happened? Why would that prevent someone rejecting astrology? This is the same as saying that "maybe the homeopaths are right because sometimes people are dehydrated and they took water; and maybe by a system of testing they adapted their framework". So what? Their actual conclusions are all wrong; we would still reject homeopath because it doesn't work, whether or not some guy was dehydrated in its history. IRWolfie- (talk) 20:19, 25 October 2012 (UTC)

One article for this nonsense is more than sufficient. The individual signs could be redirects to the one article. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:03, 24 October 2012 (UTC)

Right you are! And one article should be more than sufficient for all this nonsense that is called religion, too. 78.43.28.199 (talk) 15:16, 24 October 2012 (UTC)

Also, in the Individual astrology sign articles they used to have a detailed description of the sign and its characteristics, compatibility ect in fact if gave the best overview of any site on the web that I could find, Why has this been deleted? A good example is the Taurus article, if you go back about 6 months you can see what I'm talking about. example: http://en.wikipedia.org/enwiki/w/index.php?title=Taurus_(astrology)&diff=504352086&oldid=504350494 --Wrk678 (talk) 06:19, 24 October 2012 (UTC)

It has been deleted because it is not encyclopedic. It uses as its sources, articles like "Deborah Houlding, ‘Taurus the Bull'. The Mountain Astrologer, issue #142". I don't think a magazine about astrology really counts as a "reliable source".. The thing is, there is NO reliable source when it comes to making up clap trap, it's ALL clap trap. Compare it to the article in Britannica.. Now I'm not suggesting wikipedia necessarily should be held up to Britannica, but I think they have the right idea. If someone wants to learn about the superstitions they can learn them from a website that peddles in those superstitions.. Vespine (talk) 21:51, 24 October 2012 (UTC)

The problem isn't so much that it is claptrap - the problem is that it is inconsistent claptrap, Every astrology source says something different, as is made clear by the article history. AndyTheGrump (talk) 22:05, 24 October 2012 (UTC)

Their approach is actually completely misleading because the astronomical zodiac constellations are in different positions than the astrological zodiac (which corresponds to arbitrary segments of sky). IRWolfie- (talk) 09:24, 25 October 2012 (UTC)

I find it mildly amusing that after User:wrk678 was complaining about missing articles, he or she found it necessary to remove my comment/question yesterday. I'll repeat it for completeness: Why is this on the science desk? Even if astrology was a science, it's an article question not an astrology question - the proper place is the astrology talk page, not here. Zoonoses (talk) 04:37, 25 October 2012 (UTC)

Supersonic Newton's cradle

The steel ball in a Newton's cradle hits the other steel balls at twice the speed of sound in steel. How does this affect the solution, neglecting air resistance? 137.54.4.36 (talk) 15:54, 23 October 2012 (UTC)

Other than denting the balls, shattering them, breaking the suspending strings, or otherwise obliterating the device? --Jayron32 16:54, 23 October 2012 (UTC)

How would you get the ball to be moving at supersonic speeds? RJFJR (talk) 17:34, 23 October 2012 (UTC)

The device depends on the balls behaving as perfectly rigid objects undergoing a perfectly elastic collision (or as near as you can get in the real world). At those speeds, they would not behave in this way. Rather, the would all fuse together or break apart. StuRat (talk) 17:36, 23 October 2012 (UTC)

This answer assumes the balls are indestructible and perfectly elastic and that the strings are longer than 1900km ($h={\frac {v^{2}}{2g}})$ in order to contain the kinetic energy. Upon the first contact only 25% of the kinetic energy will be transferred due to the speed of sound limitation. The other 75% will be dissipated as heat. After the first strike the system will continue as normal, with the balls traveling at the speed of sound in steel at their fastest. A8875 (talk) 20:06, 23 October 2012 (UTC)

Terminal ballistics might be a good read. The impact of a steel ball onto a steel target is most similar to a bullet hitting an armor plate. However, the speed of sound in steel is very fast - on the order of five or six kilometers per second - which is much faster than most conventional bullets would ever travel. So, you're dealing with a sort of "fringe" regime - the theoretical behaviors of rigid body deformation have not been extensively validated in that range of parameters. In fact, this is an active area of research. Nimur (talk) 01:02, 24 October 2012 (UTC)

In the hypersonic limit, after the ball hits the other balls, the steel balls behave as a liquid. Count Iblis (talk) 16:01, 25 October 2012 (UTC)

5 cent piece coated with copper

I got a 5 cent piece (called a nickel in the US) in my change, but it's coated in copper. Could this happen naturally, say by being in contact with copper pennies for years, or is this the result of a chemistry experiment (electroplating) ? Somehow I doubt if it could happen naturally, as only the high points come in contact with adjacent pennies, but the low points are also coated with copper. StuRat (talk) 20:21, 23 October 2012 (UTC)

Per this: [[38]], it may be a nickel struck on a penny blank. I hope you didn't clean it. Dominus Vobisdu (talk) 20:37, 23 October 2012 (UTC)

No, the copper is worn off in places, and you can see the nickel underneath. StuRat (talk) 03:09, 24 October 2012 (UTC)

In that case, it may have been someone plating the nickel with copper, either electroplating or chemiplating. This is a fairly easy thing to do, because copper has a positive enough reduction potential to make it very easy to plate on other metals. I've done similar experiments with my chemistry students. We usually use nails for our plating labs, but you could do it with any metal object at all. You could even do it at home with a home chemistry kit and a decent power supply. My guess is that someone just copper plated the nickel and it got back into circulation. --Jayron32 05:15, 24 October 2012 (UTC)

(EC)The rest of this says the most common causes are electroplating, environmental damage, and science experiments. Novelty shops used to sell them. Zoonoses (talk) 05:22, 24 October 2012 (UTC)

Mitotic catastrophe

Is Mitotic catastrophe a subset of apoptosis? 140.254.226.204 (talk) 21:04, 23 October 2012 (UTC)

It looks like the view taken in the recent literature is that MC sometimes causes cell death by inducing apoptosis, but sometimes by activating other programmed cell death pathways, including one called necroptosis. Looie496 (talk) 22:58, 23 October 2012 (UTC)

October 24

Advertisement technique of image, word, and logo

I've noticed a lot of ads are rather plain lately. Specifically, they have a picture which takes up most of the frame, a large word/phrase, and a logo. For example, see Bloomberg Businessweek’s Ad Campaign. What is this form of advertisements called or classified as?Smallman12q (talk) 00:34, 24 October 2012 (UTC)

Not science, certainly. -- Scray (talk) 01:42, 24 October 2012 (UTC)

Don't know if it has a name, but it's meant as a teaser, so you will read the rest. I certainly don't read ads which present a full page of text. StuRat (talk) 03:12, 24 October 2012 (UTC)

Is there a scientific (or at least a literary) classification of ads? Just on my own I would postulate a number of classes of TV ads, for example (print ads, in concept, can be more varied, including even Wikipedia postings) --

• Allopathic - highlight/exaggerate a product's good features to make you want it
• Homeopathic - highlights a product's bad features to desensitize you to them (more common than I'd expect)
• Allegiance - directed to a third-party "customer", emphasizing that they are the top priority (3-4 years ago any program on TV would be supported by several ads that not subtly pointed out their products were usable to spy on the customer, e.g. "You talk, Sync listens" - now they are rare, not sure who/why)
• Rote - the viewer is meant to learn specific phrases which should then be easier to repeat (there is a current campaign for "Yellow tail" which is the most extreme example of this type I've ever seen)
• Cargo cult - the customer is presented with a pleasant scenario including a product, e.g. playing with a child or being with a pretty woman, which is supposed to be brought on by having it
• Identity - the viewer is supposed to believe that his kind of people just have to buy this product to show they are in the group

Now this is an ad hoc, ignorant classification, not an answer, which I use only to encourage people to consider that a serious study of the topic is possible, but I have no idea who does such a thing. Given the money involved in the industry, someone must. Wnt (talk) 14:55, 24 October 2012 (UTC)

Neuromarketing? ~AH1 ^(discuss!) 22:07, 24 October 2012 (UTC)

There must be a classification of ad styles ...what do people get MAs in marketing for?Smallman12q (talk) 22:22, 24 October 2012 (UTC)

What indeed... you asked the question... --Jayron32 03:21, 25 October 2012 (UTC)

Shape of universe

Shape of the Universe (edit | talk | history | protect | delete | links | watch | logs | views)

The three graphs in the lead are all smooth. Why? Don't some theories have irregular shapes?GeeBIGS (talk) 02:48, 24 October 2012 (UTC)

Well, all modern theories give irregular shapes at the galactic level, due to gravitational distortions of space. I think those graphs are intended to get the concept of the large-scale shape across. Looie496 (talk) 04:28, 24 October 2012 (UTC)

See Cosmological principle and Isotropy for the general idea. The Cosmological principle holds that no location in the universe is a privileged vantage point; that is for the purpose of observing the whole universe, any point should give the same perspective as any other, though local geometry may allow for variation (i.e. stars and galaxies are not locally evenly distributed) on a universe-wide level the entire universe should be isotropic and homogeneous (on average, all matter and energy should be evenly distributed). --Jayron32 05:10, 24 October 2012 (UTC)

But don't we know that the superclusters are very inhomogeneous and distort spacetime on a large scale?165.212.189.187 (talk) 16:18, 24 October 2012 (UTC)

There was once an active hypothesis that the distribution of galaxies is fractal, but I believe the current mainstream view, based on studies of the cosmic background radiation, is that it is smooth on the largest scales. Looie496 (talk) 17:06, 24 October 2012 (UTC)

The answer, 165.212, is if your scale contains inhomogeneity and anisotropy, then your scale is too small. The largest "structure" in the (observable) universe is probably the Sloan Great Wall, which is about 1/60th the diameter of the "observable universe", which itself is an unknown fraction of the actual entire universe. The Cosmological principle would hold that you need to back out your scale far enough that even structures as large as galactic filaments would "average out". I know that it is somewhat tautological, but the definition of "inhomogeneity" in the universe is almost identical to the definition of "local", that is if your perspective on the universe can identify inhomogeneous structures, your perspective isn't "backed out" enough. --Jayron32 17:23, 24 October 2012 (UTC)

My recollection from cosmology lectures during grad school is that homogeneity is a good assumption for scales that are 1/10 of the radius of the observable universe and bigger. Dragons flight (talk) 18:18, 24 October 2012 (UTC)

See [39] (from the same source as the other) or the video ([40] - a truly great video, but so crippled by jpeg artifacts in this presentation, even at HD that they're all my eyes lock onto when I try to make out the lines of the walls) Probably better sources... Wnt (talk) 19:06, 24 October 2012 (UTC)

Also see wormhole, Einstein lens and multiverse theory. Now, if it's possible that one universe could expand into another... ~AH1 ^(discuss!) 22:06, 24 October 2012 (UTC)

Blur screen for sight correction?

Is it possible to blur my monitor in such a way that it would correct my vision and I wouldn't need to wear glasses/contacts to see it properly? --89.241.237.237 (talk) 03:39, 24 October 2012 (UTC)

No. Bluring reduces the information in the image (the detail), and once removed, nothing odd about your eyes can put it back. Ratbone 58.170.172.1 (talk) 03:48, 24 October 2012 (UTC)

I don't think that's quite the whole story. It's true that turning a blurred image into a crisp image is generally impossible, but that isn't what is being asked for. If the OP is nearsighted or farsighted, in principle it ought to be possible to put a huge lens in front of the monitor that would have a similar effect to a lens in front of your eyes. I'm not sure that counts as "blurring the monitor", but it ought to work. Looie496 (talk) 04:25, 24 October 2012 (UTC)

Well, yes. But in that case it will be cheaper and a lot more satisfactory to wear suitable spectacles. Then the OP can also see his paperwork clearly, and read books as well. Ratbone 58.170.161.168 (talk) 11:14, 24 October 2012 (UTC)

If you were to trace rays from a point on your retina to your display, you could map the points on the screen that coorespond to a point in your vision. When you start mapping nearby points on your retina, you would see that the regions on the screen overlap. Unfortunately, in order to resolve this in a way that would be clear, you would have to be able to project different colors in different directions from the overlapped parts of the monitor. You would essentially need a monitor that reproduces a specific light field, so it could simulate having a lens in front of it. 209.131.76.183 (talk) 12:07, 24 October 2012 (UTC)

However, with a single object, you should be able to do it. You could have several objects on the screen at once, so long as they aren't close enough to overlap. You might also be able to quickly alternate between showing objects which do overlap, to give the impression of both being on the screen at once. This approach might have application where glasses don't work, like when wearing VR goggles. StuRat (talk) 16:28, 24 October 2012 (UTC)

No, you shouldn't be able to do it that way. As 209.131 says, it doesn't work unless you can reproduce (or heavily tamper with) the light field—something that has to be done in hardware, and can't be accomplished with a conventional display, even if only parts of the picture are displayed at a time. A straightforward thought experiment shows why. First, consider producing a sharp image of a small point of light: effectively, a single 'pixel' in our display. In a person with normal (or properly-corrected) vision, our point source of light in reality is focused to a single sharp point on the retina. In a near- or far-sighted individual, that image of the point doesn't form where it should, but falls in front of or behind the retina; instead of a sharp point, the image on the retina is a broader blur.

The neat thing about lenses is that they don't care about which way light travels through them; it gets bent in the same manner in both directions. If we instead imagine a bright, sharp point emitting light from the retina out through the lens of the eye, we'll get a blurry smudge on the computer screen in front of us. Aha! you say—if we set the computer to display that blurry smudge on the screen, we know that the lens of the eye can focus the rays from that smudge right back to a sharp point on the retina, and we've solved our problem.

...except that we haven't. While we've solved the problem of how to get a bright spot at one particular point on the retina, we've ignored the rest of the retina entirely. Unfortunately, that smear on the screen – the one that makes a sharp point in one spot on the retina – gets smeared out even further across the rest of the retina. (The rest of the retina can see the screen, too.) It can't be fixed just by picking and choosing which pixels to light up on the computer screen. (It could be fixed if there were a way to produce negative intensities—but that's beyond the scope of computer monitor technology.) TenOfAllTrades(talk) 17:15, 24 October 2012 (UTC)

Thanks, that is a good elaboration on what I was trying to say earlier. Basically, if you want that blurry smudge to resolve back into a point on your retina, each bit of that smudge has to only be transmitting light in the same direction that the imaginary light from the retina hit it. If it transmits at other angles, then it ends up hitting other parts of your eye, causing the blurry blob to get blurrier and blobbier. The sum of the thousands of blurry blobs, each pointing light in the right directions, is the light field required to render clearly on the retina. Any point on the monitor is shared by hundreds of blobs, each in a slightly different direction, so each point of the monitor would need to be able to transmit hundreds of different colors along hundreds of different vectors. I've always imagined that this technology would first show up in 3D displays - it would be like looking through a window. Leaning side to side would let you peek around and behind things, and you could focus your eyes on any object. It is pretty neat to realize it could also be used to adapt to a user's vision problems. 209.131.76.183 (talk) 19:39, 24 October 2012 (UTC)

You would need control of the phase as well as the amplitude of the generated electric field to be able to have a correction. IRWolfie- (talk) 21:09, 24 October 2012 (UTC)

Matte instead of glossy cars

Why are cars always glossy? The matte exceptions seem to be from niche design companies, but never mainstream manufacturers. OsmanRF34 (talk) 12:16, 24 October 2012 (UTC)

Because people associate "shiny" with "new". Shiny cars look newer, a desirable trait when purchasing a new car. Observe the common English idiom "shiny and new". --Jayron32 13:56, 24 October 2012 (UTC)

But a good marketing would be able to sell the idea of "matte is your mate" or something silly like that. OsmanRF34 (talk) 14:49, 24 October 2012 (UTC)

There seems to have been a recent trend toward matte paints, specifically black, in mainstream motorcycles. Just do an image search you'll see plenty. SemanticMantis (talk) 14:53, 24 October 2012 (UTC)

This is a Reference Desk, so let's try some references, shall we? At least do a bit of Googling before throwing down an opinion.

I'll start the ball rolling with these recent columns: [41], [42]. Hyundai's new Veloster Turbo apparently does come with a matte finish option, as does BMW's 6 Series Gran Coupé. So why doesn't matte appear on more vehicles?

Part of it may be price—the matte finish carries a significant cost premium (though some of that may be automakers charging what the market will bear, rather than what the finish actually costs them to apply). Part of it is certainly personal preference; go watch an episode or two of Top Gear to see very clearly how different people can have very distinct and emphatic opinions about all aspects of automobile aesthetics.

One of the key points, though, appears to be that matte finishes are a lot more delicate, and the care they require is much more finicky. No more automatic car washes. Don't even think about using standard car polishes. Don't use terry cloths, cloth, or paper towels when cleaning. If you rub too vigorously when cleaning you'll leave a shiny spot that can only be fixed with a costly respray. (For similar reasons, you can't just polish out minor scrapes and scratches.) Most people don't want to spend that much time, money, and effort on fiddling with their car's finish. TenOfAllTrades(talk) 15:06, 24 October 2012 (UTC)

Note the emphasise the point, as mentioned in TOAT's first reference in the Hyundai case at least in the US the customer actually has to sign something saying they understand the risks and special care required for a matte car. (The warranty also doesn't cover poor maintence but this can't be unique to a matte car, it's just more of an issue.) I expect this is a combination of CYA and marketing although it sounds like BMW did something similar [43]. The later ref even goes as far as to suggest a matte finish may be a bad idea if you want to drive the car daily unless you can afford to take care of it (whether yourself or paying a professional) Nil Einne (talk) 15:23, 24 October 2012 (UTC)

I suspect we're getting into a semantics question here. I believe the OP is using matte to mean "any non-shiny surface", in which case, it should certainly be possible to provide one at a low cost and with minimal maintenance requirements. The particular surface which automakers sell as a "matte finish" may be expensive and high maintenance, but let's not tar all dull surfaces with the same brush. :-) StuRat (talk) 22:29, 24 October 2012 (UTC)

StuRat got his matte finish from a roller brush and a can of house paint from the Home Depot. Someguy1221 (talk) 22:33, 24 October 2012 (UTC)

Nah... rust-colored primer, to mask the actual rust. StuRat (talk) 23:51, 24 October 2012 (UTC)

I don't think we're getting in to semantics. For starters, the OP was clearly talking about mainstream manufacturers, not what you can get from some auto store in a dodgy part of town. In any case we're discussing what's actually available. Perhaps it's possible to make this magic matte paint which is cheap, looks nice (well you didn't specify that but I assume it's a given?) but has minimal maintenence requirements. Definitely it's possible that manufacturers and from what I can tell most decent independent vendors who do custom paint jobs for some reason (for exclusivity purposes?) are only making matte finishes which have high maintenence requirements.

On the other hand, if you read the earlier sources, it seems unclear how some of the problems can be addressed. E.g. the problem with scratches. Or the fact you can't use automatic car washes (or likely any cheap manu car wash service) because they use stuff designed for gloss finishes. Even this seller of matte paint maintence products, while claiming that the maintenence requirements are overblown doesn't seem to deny these claims [44] although they of course have an incentive to discourage the use of automatic car washes which they do in all cases. The source does claim scratches can be less of an issue because they don't show up so easily which I'm not sure is true depending on the case, but it doesn't seem to deny that when you do get scratches and if they are visible you ultimately can't deal with them like you would with a gloss coat. Note that the source, unsurprisingly, also suggests if you get a bodge matte paint job from someone who either doesn't know or doesn't care what they're doing, you're likely worse of maintence wise which hardly seem surprising.

One thing which most of the sources as well as [45] mentions is that matte finishes are a relatively recent trend and therefore products to handle them are also only just really becoming available, which is likely one reason for the maintanence hassles. A key point which the Dr Beasleys source doesn't seem to answer is while it may be true the ideal maintence requirements for a gloss paint are also quite high, perhaps even higher then a matte job, what happens if you're like most car owners and can't be bothered? The other sources imply that for a variety of reasons including the obvious and already mentioned fact gloss finishes are much more common and therefore most products, experience and automatic cleaners are tailored to them, that it's likely your matte job will end up worse then your gloss job in that case. (It seems to me there's a fair chance a somewhat poorly maintained matte finish would end up looking more or less the same as an extremely poorly maintained gloss finish which likely isn't desirable.)

Nil Einne (talk) 23:54, 24 October 2012 (UTC)

Chemical Shift Perturbation

In relation to NMR, what is 'chemical shift perturbation' and is it synonymous with the phrase 'chemical shift', if not what is the difference? Please explain assuming little knowledge of advanced NMR. Thanks Kinkreet^{~♥moshi moshi♥~} 13:35, 24 October 2012 (UTC)

Perturbation means "disturbance" or "change to", so I would take "chemical shift perturbation" to mean a "change in the chemical shift (from expected shifts). In NMR, the "chemical shift" of a peak is just its location in the spectrum (usually measured as relative to the location of tetramethylsilane, for H-1 and C-13 NMR). I would understand a "shift perturbation" to be an unexpected (or non-standard) change from the expected shift. That is, you run an NMR, observe the "standard" shifts, and then usually some change is made to the substance, and you can observe a "perturbation" or "change to" the standard shifts. This page has some explanation of a kind of perturbation that occurs at the interface between two immiscible phases, that is the molecules along the interface experience a change in their chemical shift in (in this case) N-15 NMR, different from if the substance without the second, added, substance. Does that make sense? --Jayron32 13:55, 24 October 2012 (UTC)

Is the refractive index of a solution against the concentration linear?

I am doing a physics project which will involve passing a laser through an aqeous solution of Ethylene glycol(antifreeze). Does anyone know if the relationship between the refractive index of the solution and the concentration is linear or at least approximately linear? If not is there any mathematical relationship between the two?

Thanks. — Preceding unsigned comment added by 109.158.65.134 (talk) 15:48, 24 October 2012 (UTC)

The results have been tabulated [46]. It is pretty linear, though not exactly. If you can't access the article, leave a note on my talk page and I can e-mail some of the data to you. Buddy431 (talk) 16:09, 24 October 2012 (UTC)

And just to be clear, it's weight percent that's nearly linear with refractive index. Buddy431 (talk) 17:33, 24 October 2012 (UTC)

Precipitation vs Settling vs Sedimentation vs Deposition vs Decantation

Words like these don't always seem totally distinct, could someone please explain the precise definition of each, and make it clear on each article why they are separate concepts? --130.88.99.220 (talk) 16:50, 24 October 2012 (UTC)

The first three actually overlap pretty strongly. Deposition is different in that it can apply to a dissolved material -- the first three all apply to suspensions, I believe. Decantation is entirely different: it is the process of removing a layer of liquid to leave something behind. I have edited the decantation article to try to make that clearer. I'm not a chemist, and anybody who thinks my edit can be improved is encouraged to do so. Looie496 (talk) 17:01, 24 October 2012 (UTC)

I disagree about "precipitation". Precipitation (chemistry) usually applies to dissolved materials that come out of solution. Deposition (chemistry) usually refers to a layer being built up on some existing surface, either through the settling of a suspension or precipitation from a solution (where just "precipitation" might be crystals forming suspended in the solution). I would say sedimentation is a more precise term than settling: "sedimentation" is usually used for things like red blood cells that settle relatively slowly (or even smaller particles, that need a centrifuge to settle in a reasonable time scale), while the term "settling" could be used to refer to processes that occur on much shorter time scale (i.e. swirl the mixture, and then let it settle for a few minutes before decanting off the liquid). Just my 2 cents though. Buddy431 (talk) 17:26, 24 October 2012 (UTC)

(edit conflict) Deposition can refer to a solid coming out of solution, especially in contexts where the solid adheres to another surface, especially in plating, but commonly it also refers to a solid forming out of a gas: see Deposition (aerosol physics) and Deposition (phase transition); deposition is considered the proper name for the opposite phase transition as Sublimation (phase transition). The other uses are not unknown, and in some fields may be more common, but in others the phrase is reserved for a specific type of "settling", usually a solid settling out of a gas. Sedimentation is reserved for geological settings, usually: one wouldn't usually use sedimentation to refer to precipitation in a beaker in an instructional chemistry lab, though conceptually they're almost identical. --Jayron32 17:30, 24 October 2012 (UTC)

"Sedimentation" is used pretty frequently in the biology and biochemistry, with respect to how quickly macromolecules or cells will sediment, usually under centrifugation. See Svedberg and Erythrocyte sedimentation rate for examples. Buddy431 (talk) 17:37, 24 October 2012 (UTC)

Also, with regards to precipitation: my understanding (as someone with a chemistry degree who has taught the subject for more than a decade) precipitation and settling or sedimentation are distinct processes: precipitation is the formation of the solid itself, without regards for where it forms. Precipitation means specifically the agglomeration of molecules into particles in the solid phase, and happens before settling, which is the falling of those particles to the bottom of the container. Indeed, precipitation doesn't have to lead to settling: some precipitates may remain in indefinite suspension. --Jayron32 17:51, 24 October 2012 (UTC)

Maybe the people responding here could look at the articles and see if it is possible to give clearer definitions? Even a change to the first sentences alone would be valuable, if they can be made better. Looie496 (talk) 18:03, 24 October 2012 (UTC)

• Precipitation (chemistry) was just plain broken - an unsourced description given by someone who didn't seem to understand that precipitates can remain in suspension. I took a really quick slash at it but it needs proper sourcing to good texts and a lot more careful evaluation. Wnt (talk) 19:27, 24 October 2012 (UTC)

Thanks for replying so quickly guys & girls. I just wanted to add Solvation to my list of problem words, and was surprised to get some good opinions on this already. I shall check back, please keep discussing! Also my userpage is broken on this English edition but you can chat to me directly on the Arabic version. (perhaps solvation vs solution should be discussed separately?) 130.88.99.220 (talk) 20:06, 24 October 2012 (UTC)

Solvation is the process whereby the molecules/ions of the solute (the stuff going into the solution) are broken from each other and bonded to the individual molecules of the solvent. I've seen the term used inconsistently in some cases: Sometimes it refers to the entire process of dissolving: the disassociation of the solute particles and the association of said particles with the solvent molecule: it can also be used to refer to just the second part of the process, the bonding of solvent molecules to individual solute molecules/ions. In simplest terms, solvation is where individual molecules or ions of a substance get "coated" with molecules of the solvent. So when sodium chloride dissolves, the individual sodium and chloride ions get surrounded by a "shell" of water molecules that bond to the ions and thus keep them apart from each other. That's solvation. --Jayron32 02:36, 25 October 2012 (UTC)

At what temperature is surface tension on pure freshwater the strongest?

Hi. See the topic. Thanks! ~AH1 ^(discuss!) 22:00, 24 October 2012 (UTC)

At 0 deg C (below that it is solid -unless in super-cooled droplet form) as it gets lower as the temp increases until boiling point at STP. --Aspro (talk) 22:48, 24 October 2012 (UTC)

In the case of super-cooled water, this link suggest the max is at -22.2 º C : Experimental Values of the Surface Tension of Supercooled Water. Such a cloud of super-cool droplets is something any PPL holder would wish to stay away from. Does this answer your question?--Aspro (talk) 23:07, 24 October 2012 (UTC)

However, WP (as always) has an article on Supercooling and that suggests −48.3 °C. It has refs also.--Aspro (talk) 23:22, 24 October 2012 (UTC)

WHY ARE "BELT CONVEYORS" REPEATEDLY REFERED TO AS "CONVEYOR BELTS" ?

A CONVEYOR BELT IS ONLY 1 SINGLE COMPONENT OF A VERY COMPLEX SYSTEM. THE COMPLETE SYSTEM IS CORRECTLY REFERRED TO BELT CONVEYOR. — Preceding unsigned comment added by 208.86.181.160 (talk) 22:06, 24 October 2012 (UTC)

English is a remarkably flexible language, allowing a given word or phrase to have more than one meaning, and adapting the "correct" meaning to the general usage over time (as contrasted with languages that formally prescribe correctness). All that said, it appears our conveyor belt article includes both usages, and rather clearly notes that "conveyor belt" can refer to both the specific belt and the collective system. — Lomn 22:11, 24 October 2012 (UTC)

I suggest "conveyor belt" for the belt itself, and "conveyor belt system" for the entire device. A "belt conveyor" sounds like something (such as a chute) at a leather tannery which delivers leather belts from one area to another. StuRat (talk) 22:23, 24 October 2012 (UTC)

You are clearly no expert on the English language, or you would use your caps lock key more sparingly. If the OED agrees with you, maybe we can do something about it. Otherwise, no. AlexTiefling (talk) 23:06, 24 October 2012 (UTC)

The OP would do well to read the article Etymological fallacy: the original meaning of a word does not get preserved forever, word meanings change and if a word has taken on a different meaning from an older one, it isn't "wrong". --Jayron32 02:28, 25 October 2012 (UTC)

In a related vein, see also metonymy. TenOfAllTrades(talk) 12:23, 25 October 2012 (UTC)

Since you ask, AlexTiefling, the OED says: conveyor belt = an endless belt of rubber, canvas, etc., running over rollers or the like, on which objects or material can be conveyed, and belt conveyor = conveyor belt. Of course the OED derives its authority from usage and not vice versa, but I think this is a powerful argument. Marnanel (talk) 12:32, 25 October 2012 (UTC)

October 25

Can two swords really both cut the other?

I saw it in a movie once. Two swords hit hard and both appear to cut (or break) through the other. There's very little resistance, like they were pre-broken.. If anything breaks at all shouldn't one should have the upper hand? And another thing, can two swords identical enough for the ancients to accept for duelling purposes really cut each other? Sagittarian Milky Way (talk) 03:12, 25 October 2012 (UTC)

Not really cut, no. However, if they struck each other hard enough, both might shatter, and that could look the same, to the casual observer. StuRat (talk) 03:17, 25 October 2012 (UTC)

(edit conflict) I'm not sure where the line between "cut" and "break" would be, but I could imagine two swords could both cause the other to shatter or break, so that you'd end up with two broken blades. FWIW, in actual swordfighting in actual combat, there was very little sword-to-sword contact expected. In an actual melee, you didn't want to mess up the edge of your blade, and repeatedly striking it against another blade is a sure way to do that. This article here has a large section devoted to the myth of the sword-on-sword fight. It is technically a humor site (Cracked.com), but surprisingly in many articles like this, Cracked does a very good job of fact checking and providing references, as this article does. --Jayron32 03:19, 25 October 2012 (UTC)

Mythbusters tried and failed to break a sword with a sword, for whatever that's worth. —Tamfang (talk) 04:07, 25 October 2012 (UTC)

Yes, presumably because they didn't strike them together with sufficient force. Of course, it may well be impossible for two humans to do so. With the proper machinery, though, this would not be a problem. StuRat (talk) 04:30, 25 October 2012 (UTC)

Obviously you don't watch Mythbusters. When they couldn't do it themselves, per SOP, they built a machine to apply superhuman force. Correction: Grant(?) modified(?) an existing machine to apply first human force, then when that didn't do the job, cranked it up and still didn't get the hoped-for results. Clarityfiend (talk) 06:45, 25 October 2012 (UTC)

I didn't see that episode, but have seen others. They regular conclude that, because they can't do something, that it can't be done. There must be some amount of force which would shatter both swords. It doesn't surprise me if they weren't able to produce that force, however. StuRat (talk) 08:45, 25 October 2012 (UTC)

Generally for myths like that they build a rig that outperforms the best/strongest humans, and if that can't do it they claim that no human can do it. Sometimes they ramp it up afterwards, like when they used a giant pendulum (I think designed for simulating car crashes) to attempt to knock a dummy out of his socks. 209.131.76.183 (talk) 11:34, 25 October 2012 (UTC)

All of you seem to be misremembering the episode. They were testing whether a sword could cut a machine gun barrel, not whether it could cut another sword. It makes sense that a machine gun barrel would be significantly harder to cut; after all, it has to withstand hundreds of explosions every second and not break, whereas a sword's most important quality is to be sharp. The answer to the OP's question, if breaking counts as cutting, is almost certainly "yes"--swords suffer from metal fatigue over time, cracks appear, and those cracks only grow larger as the swords get used. Add to that the fact that swords made in pre-modern times could be of low quality, because metalworking wasn't as developed as it is today, and I'd be surprised if two swords didn't simultaneously break during some battle in the history of warfare. --140.180.252.244 (talk) 21:42, 25 October 2012 (UTC)

Anecdata: I was once in a theatrical production in which metal prop swords were used. In stage-fighting, there is vastly more blade-to-blade contact than in realty. In this case, the swords would occasionally simultaneously cut into one another when clashed together; the metal was soft enough that a pair of interlocking notches formed, which brought the fight to an abrupt end. AlexTiefling (talk) 07:31, 25 October 2012 (UTC)

Bear in mind that in the pre-industrial era, steel production and sword smithing was more of an art than a science, especially at the cheap end of the market or in cultures that had a poor grasp of the techniques required. Some examples from our Iron Age sword article; "Polybius reports that the Gauls at the Battle of Telamon (224 BC) had inferior iron swords which bent at the first stroke and had to be straightened with the foot against the ground." The Icelandic Eyrbyggja saga describes a similar problem: "whenever he struck a shield, his ornamented sword would bend, and he had to put his foot on it to straighten it out". A search for "broken sword blade" on Google only brings up pages of results relating to fantasy fiction and role-play games. However, Scottish Culture and Traditions By Norman C Milne says "Towards the end of the 17th century (in Scotland), we start to see broken sword blades utilised as dirk blades. This may be due to numerous factors. (John) Wallace has suggested that the local blade smiths could not manufacture blades to the same quality and temper of imported blades that were forged at Solingen and Passau." (p.99) Broken swords cannot have been unkown in England, since they appear in several coat of arms. An example is the Cartwrights of Nottinhamshire, whose arms included a crest depicting; "a wolf's head, erased or, pierced through the neck with a sword blade argent, broken off at the hilt".[47] Alansplodge (talk) 17:12, 25 October 2012 (UTC)

Another reference for sub-standard blades "Sometimes, in spite of their rigorous training, smiths were simply not "sufficyantlith ylernyd", as the Bristol masters complained in 1403. Furbours (arms smiths) in 1350 were engaged in the dangerous practice of mending broken sword-blades, instead of completely reworking them." English Medieval Industries: Craftsmen, Techniques, Products By John Blair (p.185). Alansplodge (talk) 17:34, 25 October 2012 (UTC)

AC adapter output power

I've taken the liberty of moving this to Wikipedia:Reference desk/Computing#AC adapter output power (Moved from Science Refdesk). You should get better answers, and besides, those guys have to have something to answer. :) Wnt (talk) 18:43, 25 October 2012 (UTC)

Suicide torpedoes and the Cuban missile crisis

The Mark 45 torpedo was a US, nuclear, wire-guided torpedo which apparently would destroy both ships when fired. My questions:

1) What was the intended use of such a weapon ?

2) I understand from the Secrets of the Dead Cuban missile crisis episode, that the Soviet Union had a similar nuclear torpedo called "the special weapon". Was this also a suicide weapon ? Do we have an article on it ?

3) I'm a bit skeptical of that episode, as they confused an isotherm with a thermocline. They also said that the missiles in Cuba reached the capability to destroy Los Angeles, prior to the Crisis. Is that true ? StuRat (talk) 18:45, 25 October 2012 (UTC)

For 3) It's about 2,300 miles from western Cuba to Los Angeles (per Google Earth's measurement tool). Operation Anadyr deployed both R-12 and R-14 ballistic missiles. The R-12 Dvina missiles which were already present in Cuba prior to the peak of the crisis have a range of about 1,300 miles. The R-14 Chusovaya missiles, which were on the cusp of deployment during the crisis itself had a range of about 2,300 miles. Russian Space web suggests the R-14s themselves were never delivered, but Astronautix article suggests maybe some were (with more on the blockaded ships). There's no indication that R-14's ever became active in Cuba; the Russian Space Web article says only half the R-12s were fuelled. -- Finlay McWalterჷTalk 19:27, 25 October 2012 (UTC)

Just as an aside, early submarines were essentially all "suicide weapons"; successful deployment of a charge on one often meant nearly certain death for the crew. The H. L. Hunley (submarine) had a Spar torpedo as its primary weapon. If it worked as designed, the spar would break off upon ramming and leave the torpedo inside the target boat, but I'm not sure it ever worked that well, and the boat itself was a leaky mess. You had to either have balls of brass or a brain of oatmeal to serve on a ship like that. --Jayron32 19:30, 25 October 2012 (UTC)

For 1), the claim is almost certainly bullshit; probably a garbled misrendering of some combination of historical bravado (back in my day, men were real men, with torpedoes that blew up everything) and real concerns about the possible misfortune associated with careless use of the early Mark 45. (The first generation Mark 45 – unlike the Mod 1 and Mod 2 revisions that followed – had no set minimum enabling range; they were 'live' as soon as they were fired, and a premature triggering of a nuclear-tipped torpedo was...bad...out to a much greater distance than it would be a for a conventional fish. The Mod 1 and 2 versions had a minimum enabling range of 2050 yards to prevent this sort of...incident.) Norman Friedman's U.S. Submarines Since 1945: An Illustrated Design History cover this point. A passing Straight Dope comment [48] also calls attention to the outcome of the Baker test of Operation Crossroads, which detonated a 23 kiloton warhead (twice the yield of the warhead on the Mark 45) amidst an array of ships and submarines; no submarines further than 1000 yards from the detonation were sunk. TenOfAllTrades(talk) 20:03, 25 October 2012 (UTC)

(ec) For 1), the Mk-45 carried an 11Kt W34 warhead; that's about 2/3 the yield of the Little Boy used at Hiroshima. The Mark 45 torpedo article says it was for anti-submarine warfare, with a range of up to 8 miles. The Crossroads BAKER shot, a comparable explosion depth but with about double the energy, sank the submerged USS Apogon (SS-308) at 850 yards but not USS Dentuda (SS-335) at about 1,500 yards (Dentuda returned to service after the explosion). We can see that an explosion with double the W34's energy didn't sink a submarine less than 1 mile from it; we can handwave the W34's kill radius for submerged vessels at maybe half a mile or less (a number very dependent on circumstances, as Underwater explosion shows the complexities depending on conditions). So there's no indication that a Mk-45 was an automatic suicide weapon, although obviously it's something more difficult to use effectively than an ordinary torpedo. -- Finlay McWalterჷTalk 20:11, 25 October 2012 (UTC)

And this report on Apogon's wreck says she wasn't broken or holed, but that she sank from leaking. Obviously Apogon wasn't crewed during Crossroads BAKER; we can't be sure that had she been, her crew couldn't have ameliorated the damage, pumped out the flooding spaces, and saved the boat. So that suggests the effective kill radius of the explosion was even less. -- Finlay McWalterჷTalk 20:32, 25 October 2012 (UTC)