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June 10

Crystal Glass

What is crystal glass and its special properties? —Preceding unsigned comment added by Sksinghaijbp (talk • contribs) 00:09, 10 June 2010 (UTC)[reply]

Crystal glass is a common name for lead glass. It is glass with substantial proportion of lead oxide in the mix, typically around 30% by weight. The lead content increases the refractive index of the glass, which means it sparkles more (because of total internal reflection); it also means that crystal glass is notably denser than normal glass. Physchim62 (talk) 00:27, 10 June 2010 (UTC)[reply]

And also has a lower softening point, which allows it to be shaped more easily. 67.170.215.166 (talk) 06:29, 10 June 2010 (UTC)[reply]

Growing fruits & vegetables indoors...

Possibly an extremely stupid question... if one was to grow beans, or tomatoes, or what have you indoors - wherein there would be no natural pollinators (insects, wind, etc.) would the plants still produce vegetables/fruit? should the owner attempt manual fertilization by swabbing pollen around with ... swabs or something? 218.25.32.210 (talk) 00:53, 10 June 2010 (UTC)[reply]

AFAIK beans (Phaseolus) self-pollinate. However, tomatoes do not, see Buzz pollination. --Dr Dima (talk) 01:24, 10 June 2010 (UTC)[reply]

And BTW this is not a stupid question at all; it is a very good one. Regarding the cotton swabs -- they work for some plant species but not for others. --Dr Dima (talk) 01:28, 10 June 2010 (UTC)[reply]

You can grow most food plants without polination or seeds even, see Grafting, and especially Tomato grafting which details how the method is used for indoor growing of tomatoes in light of the exact problems the OP notes. --Jayron32 01:46, 10 June 2010 (UTC)[reply]

Pikachurin 3D structure

Where can I find an image of the 3D structure of pikachurin? --75.25.103.109 (talk) 00:58, 10 June 2010 (UTC)[reply]

I don't think it is known. Working out the 3D structure of proteins is extremely difficult at best, and this protein was only characterized last year. See protein folding for more information about why the problem is difficult. Looie496 (talk) 01:18, 10 June 2010 (UTC)[reply]

But they know its sequence (otherwise they couldn't engineer pikachurin-null mice for their experiments), so can't they determine how it will fold based on the order of amino acids? --75.25.103.109 (talk) 01:24, 10 June 2010 (UTC)[reply]

Nope. The cellular machinery that synthesizes proteins is excellent at getting them to fold into their native conformation (and other chain-chain interactions). We're very far from being able to predict that result from an arbitrary sequence. In some cases we can recognize certain sequences as being helix domains or other local shapes based on homology modeling from other known protein structures. As Looie496 said, "See protein folding for more information about why the problem is difficult." It's even worse than you think, I think, because you only need a few genetic markers in order to to gene knockout. For example, it might be sufficient to inhibit a promoter or other "start" sequence, or just delete a huge chunk of genome--I can't access the Nature article to see exactly what they did. But not all of the gene base-sequence might be used anyway (see intron), so "the order of amino acids" might not be known. And there might be other post-translational modifications that are critical for certain structural features but are definitely not knowable from just the amino-acid sequence. DMacks (talk) 02:14, 10 June 2010 (UTC)[reply]

Not to contradict any of that, but perhaps to clarify a bit, working out the sequence of amino acids is cheap and easy nowadays. Working out the 3D structure is orders of magnitude harder. In fact it is only feasible in special cases, such as proteins that can be crystallized. Finding a general method for predicting the 3D structure of a protein on the basis of its amino acid sequence is currently by far the most important unsolved problem in molecular biology. Looie496 (talk) 03:49, 10 June 2010 (UTC)[reply]

What if... we're the only intelligent life

There's ongoing research as to life on other planets. What if we discover that we're the only intelligent life that we can ever travel to? Would we continue to fund extra-terrestrial expedition? If we are never going to get to where other life exists and (presuming) they would never be able to get to us (of an intellectual nature) then what would be the point in spending exorbitant amounts of money, given that we are in a global recession? Is there any research into finding ETs that might have landed on Earth that might be too small for us to detect - tiny tiny aliens landing on Earth daily who might not even realise that people are people and have developed civilisation similar to their own. Sorry to ask so many questions all in one go, but they are inter-related. --russ (talk) 01:11, 10 June 2010 (UTC)[reply]

The initial question is moot, as you can't prove a negative. As for the rest -- no referenceable answers are possible. — Lomn 01:31, 10 June 2010 (UTC)[reply]

"Exorbitant amounts of money" should be put in perspective. The world spends many, many times more money on national defense every year than on space-related sciences. And another general point - we needn't go to another lifeform's location to communicate with it. Radio-based communication is already doable, provided we know someone else is listening. 218.25.32.210 (talk) 01:33, 10 June 2010 (UTC)[reply]

Given our understanding of the laws of physics, the first question's answer is undoubtedly "We are the only intelligent life we can ever travel to." Period. The nearest stars to ours would require many centuries earth time to reach, such that any report of such missions reaching distant worlds would be received by an Earth which may have forgotten the details of the mission thus sent. The topic has been explored in song by the band Queen, the song '39, which explores the problem of time dilation in space exploration. And before we poo-poo the idea of a pop-song about a scientific topic, remember that Brian May, the writer of said song, has a PhD in astrophysics, which means he probably has a deeper understanding of the topic of the OP's question than almost any one here... --Jayron32 01:43, 10 June 2010 (UTC)[reply]

NASA Budget has some annoying numbers, but the TOTAL expenditure on NASA in 2007 dollars has been either $416 billion or $807 billion, averaging $8 or $16 billion a year, respectively. From that same article, the aerospace industry (of which NASA is the largest, not sole, member of) "contributed more than $95 billion to U.S. economic activity." As a means of comparison, according to Military budget of the United States, the military expenditure for 2010 is/will be somewhere between $880 and $1000 billion. That may be a tad disingenuous since the military is the largest portion of the budget, but Medicare/aid and Social Security aren't far behind; the point stands, though - aerospace is not a huge source of spending, and almost certainly gives back more than it takes. (I'm using NASA since it's a. the largest of it's kind, b. our articles on the US are better/easier to find info on, and c. other agencies/countries aren't looking nearly as closely as the USA is.) ~ Amory (u • t • c) 14:07, 10 June 2010 (UTC)[reply]

Indeed, the dropping of the Orion spacecraft could easily be avoided if we went without an extra stealth bomber. Not that I disagree with the project's cancellation, mind you.-RunningOnBrains^(talk) 14:49, 10 June 2010 (UTC)[reply]

Before saying that the answer is undoubtedly that we are the only intelligent life we can ever travel to, take into consideration that it was once deemed impossible for man to sustain powered flight, and that I am told many felt the same way about breaking the sound barrier. Certainly within our understanding of physics we can't travel to other planetary systems, but that's assuming that we understand everything that we can about physics. I guarantee that in two-hundred years, some of our theories will be laughed at by our descendants (assuming, of course, that we don't destroy civilization before then). Falconus^{p t c} 04:02, 10 June 2010 (UTC)[reply]

Well, of course. If the world doesn't work how we think it works, then all bets are off. Magic fairies may someday take us to fantastical lands where we never grow up, but given that we don't have any evidence of such fairies existing, we must operate as if they do not. Likewise, until the real problems of the speed-of-light limit are shown to be false, we shouldn't operate as though it is really possible. If we ignore the laws of physics as we understand them to behave, then there's no need to confine ourselves to any reasonable answer within those laws. We could just travel to far away planets by flying carpet for all that matters... --Jayron32 04:48, 10 June 2010 (UTC)[reply]

See Fermi paradox. We might start to terraform other planets in the absence of life. ~A H 1^(TCU) 01:59, 10 June 2010 (UTC)[reply]

It's of note that the prospect of hanging out with intelligent life was never the official justification for space research and exploration. There are lots of other reasons to think that exploring space is a worthwhile endeavor (to at least certain costs). --Mr.98 (talk) 02:18, 10 June 2010 (UTC)[reply]

What if is not a very good title for a qustion. Dauto (talk) 02:22, 10 June 2010 (UTC)[reply]

I changed it. Ariel. (talk) 04:02, 10 June 2010 (UTC)[reply]

What does a global recession now have to do with spending money on space faring pursuits over a time span of hundreds or thousands of years? Dismas|^(talk) 02:52, 10 June 2010 (UTC)[reply]

I'm not sure who you're asking, but there's a real chance that we may have a limited window to take certain first steps. Energy and raw material shortages could make such big science projects more and more political unfeasible. The irony would be that a more advanced space program would help solve these issues, but if the underlying technologies haven't already been explored there's a chicken-egg problem. APL (talk) 05:18, 10 June 2010 (UTC)[reply]

to reiterate what Falconus said, the nature of science is such that every scientific claim implicitly ends with the phrase "...given our current state of understanding." The scientists 50 or 100 years from now will be just as astounded by our ignorance as we are astounded by the ignorance of people who believed in alchemy and divination. I mean really: Benjamin Franklin was a very bright guy by any standards, but he would have laughed at the idea that people could get from the Americas to Europe in a matter of hours by flying through the sky in a big metal tube, higher than any bird. --Ludwigs2 07:32, 10 June 2010 (UTC)[reply]

Nitpicking, but your scales are off. 50 years ago was the start of the space age, and 100 was a few years past the airplane. If you want to compare to Ben, you gotta look to 2250. ~ Amory (u • t • c) 13:43, 10 June 2010 (UTC)[reply]

nitpciking your nitpick, but you seem to think that technology is linear, where technology seems to be a more exponential model. Googlemeister (talk) 14:36, 10 June 2010 (UTC) [reply]

Uhm I'm in a position to give an authoritative answer. Intelligent life does exist outside this solar system and there is travel between different civilizations, even over distances of millions of light years. The human civilization on Earth, however, is not regarded to be a real intelligent civilization by most of these civilizations, though. To qualify, a civilization must have developed the technology to expand itself at an exponential rate. Human civilization has yet come up with any production process that is capable of exponential growth. E.g. think of nano-tech factories that can copy themselves.

Obviously, all the civilizations that meet the criterium for being an intelligent civilization, are machine civilizations. In some of these machine civilizations, the ancesteral biological beings are kept in Zoos or Wild parks. Population control usually proceed along these lines.

Despite the inferior nature of human civilization, I find the lack of imagination in this thread about space travel strange. I mean, isn't it obvious that space travel between civilizations happens using data transfer via wideband communication channels? If you want to transfer a file to someone living far away, you don't put your computer in your backpack and travel all the way to the destination, either! Count Iblis (talk) 14:50, 10 June 2010 (UTC)[reply]

^{[citation needed]}... Nimur (talk) 15:30, 10 June 2010 (UTC) [reply]

No...but if you want to travel to Prague you don't send someone in Prague an email. ~ Amory (u • t • c) 16:01, 10 June 2010 (UTC)[reply]

When you travel to Prague what you are doing is carry your brain to Prague. If your civilization were more advanced, your brain would run on some machine and you could upload it to a compatible machine in Prague. Count Iblis (talk) 16:24, 10 June 2010 (UTC)[reply]

So then would the consequences of a blue screen of death be literal death? Googlemeister (talk) 19:06, 10 June 2010 (UTC)[reply]

It must be pointed out that when a country spends a lot of money to create and launch a space probe, the country does not just gather a big pile of taxpayer cash and launch the money at Neptune, never to be seen again. Most of the money is paid over the years to the scientists, engineers, technicians, administrators, and other staff who work on the project, whether they're government employees or private vendors. All these people then use the money to pay rent, buy food, and go to the movies. Keynesian economics claims, among other things, that government spending like this increases demand and consumption, thus boosting and not degrading the economy. Also see the Government spending article. Comet Tuttle (talk) 19:33, 10 June 2010 (UTC)[reply]

What if we discover that we're the only intelligent life that we can ever travel to? -- I think we have already more or less realized that this is true. There does not appear to be any intelligent life other than us within our solar system - and getting to even the nearest other star is close to impossible. If we don't find intelligent life within (let's say) 50 light years (and we've certainly studied those few stars pretty carefully) - there is essentially zero chance that humans will ever go there in person. We just don't live long enough and the speed of light is a harsh mistress!
Would we continue to fund extra-terrestrial expedition? -- Evidently we do! Yes!
If we are never going to get to where other life exists and (presuming) they would never be able to get to us (of an intellectual nature) then what would be the point in spending exorbitant amounts of money, given that we are in a global recession? -- You have subtly switched from asking about intelligent life - to life in general. We are spending modest amounts of money looking for non-intelligent life in our solar system - but there are good chances that that could be successful. Outside of the solar system, really, the SETI program is the only substantial effort to look for intelligent life - and that organization is run on a shoe-string. But there would be immense value to humanity just to know that we are alone - or not alone...either way would probably have a fairly profound effect on us. Even finding unintelligent life with the solar system would tell us a lot about evolution and where we come from. If we found intelligent life within a reasonable number of light years, we could communicate with them by radio or perhaps laser and exchange knowledge. That would certainly be an exciting and valuable prospect.
Is there any research into finding ETs that might have landed on Earth that might be too small for us to detect - tiny tiny aliens landing on Earth daily who might not even realise that people are people and have developed civilisation similar to their own. -- Not really. There are quite serious limits to how small something can be and still have enough brain power to be called "intelligent". Notice that our computers are coming close to the limits of "Moores' Law" and they are nothing like powerful enough to be intelligent. The volume of the human brain is likely to be close to the smallest it can be for our level of intelligence...I would be very surprised if a life-form smaller than a mouse could possibly have enough computing capacity to be intelligent. So there is really no point in looking for microscopic-but-intelligent life. However, unintelligent "aliens" could easily be here in the form of bacteria and viruses that travelled here by comet or meteor from other planets or even further afield. The "panspermia hypothesis" suggests that it's possible that all life on earth originated elsewhere in the universe - and that we're all (in a sense) "alien".

SteveBaker (talk) 00:24, 11 June 2010 (UTC)[reply]

I would point out, with regard to your point 1, that we might someday live longer. --Trovatore (talk) 00:27, 11 June 2010 (UTC)[reply]

We might - (although you'd need to be able to live for a few thousand years, cooped up in a tiny spacecraft, living on the same recycled food/water/air...that's one hell of a stretch!) but it would be wrong to conclude that SETI carry on their search in the hope that human lifespans will someday be long enough that we can travel the 100 light years it might take to get to the nearest intelligent aliens. They are doing it purely for the answer to the simple yes/no question "Is there anyone out there?" - even if they found an alien civilization via a radio message, it's very unlikely that anyone alive today would live long enough to talk to them! This is simple human curiosity - it has nothing to do with whether we might travel to meet aliens. SteveBaker (talk) 00:45, 11 June 2010 (UTC)[reply]

If we compare human colonization of other planets to human history then we are early humans stuck in a small range in africa. Eventually I think we will spread throughout the galaxy through colonization, although in small leaps of a few lightyears over a very long time, none of the colonies knowing of many others or being able ot contact many others. If a faster method of travel is ever discovered, then that will be like the beginings of current civilisation and as it is refined, exponential growth until the colonial age and now.--178.167.179.162 (talk) 22:59, 11 June 2010 (UTC)[reply]

Interesting properties of acetic acid

Hi. The chemical structure of acetic acid (CH₃COOH) appears to have the same number of each atom as the combination of methane (CH₄) and carbon dioxide (CO₂). Could lightning, for example, split the molecules should it strike vinegar and convert it into these two greenhouse gases? Could it similarly form acetic acid from the gases? Also, assuming that the acid is an aqueous solution, removing the water molecule produces C₂H₂O. Again separating H₂O would produce water and C₂, or diatomic carbon. Could a reaction between carbon and water from lightning, or even in carbonic acid, produce acetic acid (and oxygen, in the case of carbonic acid)? Could this be a useful way of obtaining vinegar by manufacturing it, or even producing hydrogen electricity by obtaining the hydrogen from the acid, or would that apply to all acids as well as water? As an aside, when metals react with strong bases such as sodium hydroxide and a thin layer of bubbles coats the metal, do the bubbles contain both hydrogen and oxygen gas? Thanks. ~A H 1^(TCU) 02:28, 10 June 2010 (UTC)[reply]

See the articles Carboxylation and Decarboxylation. The addition of carbon dioxide to methane to form acetic acid is an unsurprising reaction, as is the reverse, and these are routinely discussed in introductory organic chemistry classes and textbooks. A very similar reaction to what you describe, using electricity, is noted at Kolbe electrolysis. --Jayron32 02:50, 10 June 2010 (UTC)[reply]

Metals - just hydrogen gas in the bubbles.83.100.132.26 (talk) 15:12, 10 June 2010 (UTC)[reply]

Tiger question (not about the big striped cat)

Suppose an Allied commando team steals a Tiger tank from the Nazis and, while driving it toward the Allied lines, encounters another Tiger. Would the two Tigers be able to destroy each other, or would they end up shooting at each other without effect like the Monitor and the Merrimack? Or does it depend on their position relative to each other? (Assume that they both have identical 88mm guns and standard armor.) Thanks in advance! 67.170.215.166 (talk) 03:15, 10 June 2010 (UTC)[reply]

In Kelly's Heroes, a highly underrated movie, the point is made that the Tiger was quite weakly armored in the rear. So even if they could stand each other off face to face (which I'm not sure about), you would get an interesting situation once one passed the other. Looie496 (talk) 03:38, 10 June 2010 (UTC)[reply]

According to http://www.worldwar2aces.com/tiger-tank/ "Depending on the type of ammunition used, the Tiger's 88mm has a muzzle velocity of 930m per second and could penetrate up to 110mm of armor at a distance of 2000 meters"

According to http://www.fprado.com/armorsite/tiger1.htm the armour was 80mm at the rear, 100mm at the front at mostly nearly verticle angles, and 120mm around the gun mantle.83.100.132.26 (talk) 13:54, 10 June 2010 (UTC)[reply]

Clearly rear and side shots would work, frontal shots - don't know.. It's worth reading the whole article - thickness is one factor, quality is another - the tiger steel was rolled nickel alloy plate . it's not clear to what type of armour the penetration figures refer.83.100.132.26 (talk) 13:57, 10 June 2010 (UTC)[reply]

Even if you can not penetrate the armor in one hit, you could still cause damage. Spalling, hits to unarmored areas like tank tracks, multiple hits to one area of armor can all take a toll. Also, the above chart is done at a range of 2000 meters. If you are only 200 meters, your shot should have at least some additional power, perhaps enough to penetrate the armor anywhere on the tank. In the battle between bullet and armor, bullet almost always has the upper hand. Googlemeister (talk) 14:51, 10 June 2010 (UTC)[reply]

baking soda

why cant u eat baking soda unless its dissolved in water first. it says not to on the box, that it will cause some kind of severe stomach problem like bleeding ulcers or something. what will happen? —Preceding unsigned comment added by Alexsmith44 (talk • contribs) 03:47, 10 June 2010 (UTC)[reply]

Its probably a liability issue. Eating straight baking soda could cause problems because of the rapid release of carbon dioxide gas in your stomach, and the company needs to cover its ass by saying not to do it, so that you can't sue them if something goes awry. Baking soda certainly has medicinal uses, see Sodium_bicarbonate#Medical_uses, but the people who make boxes of baking soda are probably understandibly going to discourage you from using their product, unregulated, as a medication. --Jayron32 03:58, 10 June 2010 (UTC)[reply]

it says it fine eat use as long as u dissolve it in water first and drink it. why cant u eat it as a dry powder though? what kind of stomach problems can it cause? —Preceding unsigned comment added by Alexsmith44 (talk • contribs) 04:12, 10 June 2010 (UTC)[reply]

As a dry powder, it rapidly produces carbon dioxide gas when it comes into contact with any acid, such as the hydrochloric acid in your stomach. Even a few grams of sodium bicarbonate could produce several liters of carbon dioxide gas; this could be either uncomfortable or dangerous depending on how fast you could expel the gas relative to how fast it is produced. Basically, if you can't burp faster than the gas is produced you could do actual damage to your stomach. When dissolved in water, you are diluting the sodium bicarbonate to the point where it will produce carbon dioxide much slower, and thus is unlikely to cause a problem. --Jayron32 04:18, 10 June 2010 (UTC)[reply]

can it cause bleeding ulcers ? —Preceding unsigned comment added by Alexsmith44 (talk • contribs) 04:23, 10 June 2010 (UTC)[reply]

Peptic ulcers are primarily caused by the Helicobacter pylori bacteria, so it is unlikely to cause "bleeding ulcers" under the conventional, medical definition of the term. However, if the gas pressure inside of your stomach due to the release of carbon dioxide is great enough, it could in theory cause the stomach to partially rupture, which can lead to bleeding of the stomach. So, yes, it can be accutely dangerous to consume spoonfulls of undiluted sodium bicarbonate. No, it cannot cause stomach ulcers, which are a chronic medical condition unrelated to what you eat. --Jayron32 04:30, 10 June 2010 (UTC)[reply]

I was under the impression that while most gastric ulcers contained H.p. bacteria, that it was not clear if the bacteria themselves caused the ulcer or if they just colonized it after it formed. I don't know if it has been definitively determined what precisely causes ulcers. Googlemeister (talk) 14:34, 10 June 2010 (UTC)[reply]

As mentioned in the Helicobacter pylori article (though somewhat buried) researcher Barry Marshall demonstrated that H. pylori can be the causative agent of ulcers by drinking a culture of them. Numerous subsequent studies have demonstrated that ulcers can be alleviated by treatment with antibiotics (also indicating a bacterial origin). Of course, that only shows that some ulcers are caused by H. pylori, not that all of them are. -- 174.24.195.56 (talk) 15:02, 10 June 2010 (UTC)[reply]

Most toy rockets use baking soda and vinager as a fuel to give you an idea of how dangerous consumming a spoonful of soda might be, especially on a full stomach with absolutley not room for any gas. 71.100.0.241 (talk) 12:51, 10 June 2010 (UTC)[reply]

question on cars and automated transmission...

Im a Medical Doctor so my knowledge on cars and engineering mechanics is limited so pardon me if the question is pretty infantile. however i would appreciate answers which are explanatory. question is : if we take two identical cars - say two toyota landcruisers, 6 cylinder 4 wheel drive top end model, one is manual transmission ( meaning manual gear system) and the other is automated transmission ( automatic gear change) which one would be more fuel consuming - or to put it the other way which model will consume less fuel?

most people say the automated transmission is a FUEL GUZZLER and would waste a lot of fuel but I feel in an anutomated transmission car, chances of the driver using the clutch and brakes are lesser and as a result it would actually save fuel... explain pls... —Preceding unsigned comment added by Fragrantforever (talk • contribs) 04:31, 10 June 2010 (UTC)[reply]

For the same model of car, the difference between a stickshift and an automatic transmission is small, but measurable. That is, a stickshift Hummer is unlikely to get better fuel mileage than a automatic transmission Honda Civic, but when choosing between to versions of the same model of car, the stickshift invariably gets a few better miles per gallon. See this article by Consumer Reports, which found that stickshifts got about a 2-3 mpg improvement over their automatic counterparts, and also performed better in terms of acceleration. I'll leave it to the engineers to explain why this is so, but it is undoubtedly a real effect. --Jayron32 04:41, 10 June 2010 (UTC)[reply]

Automatics are not the gas-guzzlers they once were, and the fuel efficiency of the manual depends on the driver's skill at manipulating the transmission, but in general they(automatics) are still less efficient.

It's important to note that an automatic transmission works differently than a manual one. It's not like you've got a manual transmission with a robot shifting for you, It's a different type of mechanism. So most of them do actually have less efficiency than a standard car of the same model, assuming the standard driver has a reasonable level of skill.

Nowadays, there seem to be exceptions to that once hard and fast rule, though. Check out these numbers for the 2000 RAV4 : [1][2]. If these numbers are right, then the auto is slightly more fuel efficient, especialy on the freeway. I'm not sure what causes that. APL (talk) 05:05, 10 June 2010 (UTC)[reply]

Autos always were less efficient since most of them use a torque converter instead of a clutch. This works rather like slipping the clutch all the time, and since it slips, it wastes power and therefore fuel. More modern autos can lock up the torque converter - normally in top gear - and this makes them more fuel efficient and approach the efficiency of manual transmission. My guess is that where the auto is more efficient than the manual (e.g. the RAV4 above), then this is down to the different gear ratios used - probably the auto has a higher ration "overdrive" top gear. --Phil Holmes (talk) 07:45, 10 June 2010 (UTC)[reply]

It should go without saying, but how the manual transmission vehicle is driven will also affect mileage. Consider the case of a driver travelling at constant speed. The automatic transmission will generally try to keep the vehicle in the highest reasonable gear in order to maintain the lowest engine speed and minimize fuel usage (I'm simplifying somewhat). In practice, this may mean shifting up into top (overdrive) gear even at quite moderate speeds, as long as the vehicle is not accelerating. The driver with a manual gearbox may not be quite so aggressive about upshifting (for convenience, out of absentmindedness, for fear of stalling, because they like to weave in and out of traffic and need the torque, or because they just never learned to do so). In this situation, the mileage of the automatic may well exceed that of the manual, where the manual is not being driven optimally for fuel economy. TenOfAllTrades(talk) 13:03, 10 June 2010 (UTC)[reply]

One additional factor is that a manual often (but not always) has more gears than an automatic of similar vintage. This can make it slightly more efficient also. There are even a few "automatic" transmissions these days that use the architecture of a manual, but with solenoids doing the clutching and shifting for you. These should be more efficient than a conventional automatic, but I believe right now they're found only on a few very high-end cars. Friday (talk) 14:57, 10 June 2010 (UTC)[reply]

Not anymore. The DSG is at least 6, more commonly 7 gears which is an overkill for a reasonable car with manual. As soon as the Japanese catch up ... East of Borschov (talk) 15:53, 10 June 2010 (UTC)[reply]

I'm not an engineer, but having about 20 years of observational experience I will say (for 90% of it) the difference is the number of gears. Automatics of yore had 3 (gasp!) or 4 gears, maybe one overdrive (basically a taller top gear) so when accelerating you spent a lot of time at a sub-optimal RPM. Manuals are typically always 5 well spaced gears, some 6. However; modern cars (mostly japanese and european) are making 5 or 6 speed automatic transmissions standard and on these models you are seeing the difference between the MPG rating of the manual and automatic versions almost disappear. Ultimately if you drive a modern car and if you are really soft-footed you can get a great MPG out of either kind of car. It all comes down to how much time the motor has to spend at an awkward (usually high) RPM. --144.191.148.3 (talk) 13:35, 11 June 2010 (UTC)[reply]

If you are a good driver, and you know how to shift such as to be fuel efficient you can save about 5% by driving stick - mainly because of losses through the complicated automatic transmission mechanism. If you are a terrible driver or if you simply enjoy revving the heck out of your car - then the automatic will be able to moderate that and you'll get better mileage with the automatic gearbox. However, you would be surprised at how hard it is to drive a manual gearbox in a really fuel-efficient manner...you need to keep the RPM strictly within the 1500 to 2500 range (or perhaps 2000 to 3000, depending on the type of car). I can practically guarantee, you'll notice you're going over that when accelerating in-town. To keep within that range, you'll be doing a LOT of shifting! SteveBaker (talk) 23:53, 10 June 2010 (UTC)[reply]

Thanks for all the answers...appreciated... Fragrantforever 05:10, 11 June 2010 (UTC) —Preceding unsigned comment added by Fragrantforever (talk • contribs)

Sapphire Question

I had asked a question relating to Blue Sapphires earlier but this is different. To cut a long story short I finally found the Blue Sapphire I was looking for and a jeweller sold me a very expensive 5 carat sapphire set in a gold ring. Is it possible I could through some experiemnts/ tests confirm it is indeed a blue Sapphire and not any other imitation blue stone? Is it possible to check if the colour is indeed naturally deep blue or wheteher it was heat treated to take this brilliant deep blue hue colour? I have read unscruplous jewellers heat the Sapphire to increase the colour from a pale blue to a brilliant deep blue. Is it possible to check if the stone was heated to improve its colour? Though these questions might sound trivial, let me tell you I have very personal and sentimental reasons for asking - to ensure it is indeed a blue Sapphire and not any other imitation blue stone and that it is not heat treated Fragrantforever 07:22, 10 June 2010 (UTC) —Preceding unsigned comment added by Fragrantforever (talk • contribs)

From what I could see on the article, it's pretty hard to tell (there is some mention of loss of "silk", making the stone more transparent). You more or less have to trust the certificate they gave you. You can try looking at it through a magnifying glass, but you would need to know what to look for. Did they give you a certificate? What does it say? Who's it from? Ariel. (talk) 08:47, 10 June 2010 (UTC)[reply]

What you do is to agree to buy the sapphire on condition that you may return it within (let's say) three days and get all of your money back. Then you go to a rival jeweller and state that you wish to sell this valuable Blue Sapphire. They will check it meticulously and tell you if it's a fake. If it is, you take it back, if it is not then you politely decline whatever money they offer you (unless it's way more than you paid for it!). SteveBaker (talk) 23:26, 10 June 2010 (UTC)[reply]

Not sure I agree with the entire thing here. If the second dealer you take it too is not 100% above board (and a significant % might not be), then he/she might try to take advantage of you by telling you that it is fake, or of low quality and will offer only a low amount, even if the sapphire is indeed high quality. Googlemeister (talk) 13:21, 11 June 2010 (UTC)[reply]

Thanks to Ariel and Steve for your replies, Steve your answer in particular is brilliant and yet a very easy solution to the vexing problem i face... yes I remember the jeweler telling us he would take the Sapphire back if I felt it wasnt lucky for me... so far its been lucky for us I guess... But I will follow your advice and take it to another jeweler telling them I wanna sell it... sounds like a brilliant suggestion... thanks for the answer. Fragrantforever 05:17, 11 June 2010 (UTC) —Preceding unsigned comment added by Fragrantforever (talk • contribs)

indoor door frames

are indoor door frames made out of solid real wood or plywood. and is it a treated wood? —Preceding unsigned comment added by Alexsmith44 (talk • contribs) 10:33, 10 June 2010 (UTC)[reply]

If they are light, most likely they are just a plywood or particleboard box (hollow inside). --Chemicalinterest (talk) 11:18, 10 June 2010 (UTC)[reply]

Depends when the house was built. I've renovated a couple of Victorian houses in the UK, and the door and window frames were either pine or deal. Newer houses in the UK probably use pine. Can't say whether they're treated or not - what would they be treated with, and for what purpose? --TammyMoet (talk) 12:37, 10 June 2010 (UTC)[reply]

On that last point, I assume the reference is to pressure-treated wood or some other form of wood preservation. As far as I know this sort of thing is only done for wood to be used outdoors unpainted, where it will be exposed to weather. --Anonymous, 18:09 UTC, June 10, 2010.

The question is about frames. These need to be solid timber for strength, and the thickness will depend on the weight of the door(s). They would not normally be treated, except by being seasoned, and painted.--Shantavira|^{feed me} 12:36, 10 June 2010 (UTC)[reply]

The frame would indeed be "real" wood, though there may be multiple pieces of 2x4 or whatever to get the desired thickness. I don't think they're typically painted, though, as they're (usually?) internal - they provide the structural support and not much else). The opening of the door is also surrounded ("framed" in the everyday sense, though not the carpentry sense) by decorative material that often is painted and may be made of either natural wood or any one of the several kinds of composite wood-based products on the market. This decorative material is usually made to match either the footboards/toeboards or the door itself if it's been decorated. Standard pressure-treated lumber is not suitable for interior use because of the toxins it exudes (or at least used to; I'm not up on the latest developments). Matt Deres (talk) 18:58, 10 June 2010 (UTC)[reply]

You can see new door frames on sale in the UK at Wickes and B&Q, presumably in other countries you can see them in the equivalent DIY stores and ask what they are made of. In the UK they would be solid pine (could be FSC-certified) or MDF. In France the door frame and door are sold together (a "door set") and solid pine is common there too. Itsmejudith (talk) 22:47, 10 June 2010 (UTC)[reply]

glycemic load determination

Many people complain that while glycemic load determination methods try to address factors like particle size there are a variety of methods being used and only a relatively few foods are listed for each method. Wouldn't it be better to measure glycemic load by simply showing the rate at which a particular food is oxidized, i.e., converted to water and carbon dioxide similar to the way in which the speed of the wave front is used to determine the power of an explosive? 71.100.0.241 (talk) 12:19, 10 June 2010 (UTC)[reply]

Because particle size is related to the rate of reaction. To use your explosive analogy, one pound of gunpouder contains a fixed amount of energy. If I spread it in a thin layer in a pan, it will release the same amount of energy as when I pack it closely in a pipe. But, the rates of reaction, and the velocity of the shock wave (I doubt the pan will have a shock wave) will be different. —Preceding unsigned comment added by Hacky (talk • contribs) 17:49, 10 June 2010 (UTC)[reply]

So by the same token glycemic load is not accurate unless you state whether the ingredients were blended and liquefied or eaten whole so the method preparation has to be analyzed and stated. 71.100.13.202 (talk) 20:57, 10 June 2010 (UTC)[reply]

the best it could be?

Resolved

what about the argument that a huge company like Philip Morris has no interest in having their customers die off (perhaps accounted for as "attrition" in their sales forecasts), so insofar as they have any control over the formulation, yes, their R&D would make it as addictive as legally possible (or the most they can get away with in PR terms) but also the least lethal they can -- I mean doesn't that stand to reason? Philip Morris is a Fortune 100 company, I am sure their research department doesn't just get their additives from a tire melting plant on the theory that it is cheapest, indeed the tire melting operation could even be paying them to take the waste off their hands?

Note: I started smoking because of your health effects of smoking article, so if you want to attack me, why not go straight to that source and remove the spin, if you can - and if you can't, my theory is that it isn't spin. 92.229.12.67 (talk) 13:50, 10 June 2010 (UTC)[reply]

I'm not sure what the heck you're talking about. The article clearly states that smoking is a dangerous activity, that is likely to have many different, mostly negative, impacts on your health (Including a terrifying 1-in-5 chance of lung cancer!), and will significantly reduce your estimated life expectancy.

As for your theory, it's good as far as it goes, but there are two major strikes against it. First, unfortunately the basic operation is fundamentally dangerous. You're burning plant material, and sucking the resulting smoke into your lungs. They don't have to do anything special to cigarettes to make them dangerous, it's just that smoke itself is fundamentally bad for you. Second, most efforts to remove the dangerous components from smoke (better filters, etc) also remove the most flavorful components. In fact in some cases they might be the same components. The primary main concern of the cigarette manufacturers is to make sure that existing smokers choose their brand instead of competing brands. This makes sense. If Marlboro suddenly changed their cigarettes so that they were much safer, but had a boring taste, smokers would just smoke some other brand. Then Marlboro would go out of business, and the smokers would still destroy their lungs. APL (talk) 14:29, 10 June 2010 (UTC)[reply]

Someone who started smoking because they read an article saying it ruins your health, makes you impotent, and then it kills you. Should it have mentioned it give you bad breath and makes your toes fall off or would that have encouraged you? I think that merits the slow lingering Darwin Award. Dmcq (talk) 15:17, 10 June 2010 (UTC)[reply]

I can give you a line by line analysis of what parts, probably added by someone on Tobacco's payroll, convinced me. For starters, the article is called health effects: in English the grammatical meaning of that phrase is arrived at through association with other noun + noun phrases. What is a school bag? So, anyone who is worth six figures due to their education knows that "health effects" has a positive meaning, since health is a positive word. I can give you further analysis line-by-line, but the upshot is that the article convinced me to smoke, and is still convincing to this effect. 92.229.12.67 (talk) 15:24, 10 June 2010 (UTC)[reply]

(e/c) I think what the IP is trying to say (in a somewhat awkward manner) is that a company like Phillip Morris (or for that matter like Toyota, or BP, or Dow Chemicals) sees the deaths of clients or passers-by as a financial risk to be insured against rather than a moral dilemma. The tobacco industry is far more concerned about being asked to pay for lung cancer treatment than it is about being the cause of lung cancer, and it will continue to produce cigarettes so long as it can shift the financial burden of lawsuits and medical care (and etc) off onto the customer. which it does very effectively - why do you think the US government taxes the sale of cigarettes to apply to medical funds - which comes straight out of the consumers' pockets without affecting the corporations' bottom lines - rather than forcing the corporations to set up a medical trust - which would come out of corporate profits, and might affect shareholder interest.

According to classical macroeconomics, whether the tax is on the consumer's side or the supplier's side doesn't affect who is impacted the most -- only the elasticity of supply/demand. Unfortunately, the elasticity situation does minimal overall effect on the supplier at the expense of the consumer. (See tax incidence) John Riemann Soong (talk) 15:55, 10 June 2010 (UTC)[reply]

as to why the IP thought that our article was a good reason to start smoking... agree with the Darwin Awards suggestion, except that slow death by tobacco will allow him to live well past breeding age, and so his choice may not benefit the human genome. C'est la vie. --Ludwigs2 15:37, 10 June 2010 (UTC)[reply]

The ghoul in me says the original argument is flawed in that it supposes the current levels are substantially above what's necessary and sufficient to be likely addictive--that there really is a "therapeutic" window being exceeded. Even more ghoulish, they really do need to keep these levels as low as possible because "too much" toxin leads to too rapid a death...not living for many years of habitual smoking makes the product less profitable. DMacks (talk) 15:47, 10 June 2010 (UTC)[reply]

If you have specific concerns about an article, please discuss them on that article's talk page; the Wikipedia Reference Desk isn't really the appropriate place. Moreover, nowhere on Wikipedia is an appropriate place for soapboxing and general commentary; you can use your Facebook page or Twitter account for that. TenOfAllTrades(talk) 15:46, 10 June 2010 (UTC)[reply]

I particularly like 92.229's ham-fisted attempt at guilting us into doing ... something. Oh yes. "Because I detected some errors in your Wikipedia article, (Probably added by someone trying to introduce misinformation.) I have decided on a course of action that has very high likelihood of killing me." Very convincing narrative right there. It reminds me of the time I drove 185mph in a 35 zone because someone had used spray paint to graffiti the speed limit sign.

I'd better go turn the article into a ridiculous, cartoonish, hack-job so that someone like 92.229 doesn't start smoking because we didn't exaggerate its deadly effects enough!!!

Seriously, how old are you? Ten? APL (talk) 16:08, 10 June 2010 (UTC)[reply]

Trolls are ageless. Comet Tuttle (talk) 20:46, 10 June 2010 (UTC)[reply]

Sorry, you people are misunderstanding why I say Philip Morris research would try to reduce the impact of death as far as they can: it is because the estates of deceased don't continue to buy cigarettes on behalf of the dearly departed. I thought it would be obvious. If I have dues-paying members of my cult, and my cult is a fortune 100 company, then why would I want any of them to die? Obviously I don't. 92.229.12.67 (talk) 16:04, 10 June 2010 (UTC)[reply]

We're not stupid. We understand your point. Now understand our point : You Are Wrong. There is no way to make cigs safer while keeping them desirable. It is the smoke itself which is dangerous. They could construct a cig so that less smoke goes into your lungs, but who the heck would buy that?

It'd be like McDonalds replacing all their unhealthy food with green salad. Sure their customers would live longer, but they wouldn't have any customers! Everyone would just go to Burger King. APL (talk) 16:08, 10 June 2010 (UTC)[reply]

However, you may be interested in Cigarette filter, and Light cigarettes which are efforts to make cigarettes safer, just like you say. Filtered cigarettes seem to have caught on, but most people say that lights just don't have the flavor they're looking for.

I'm not a smoker so I couldn't say for sure.

Doesn't matter though, research has shown that the health benefits of switching to "Lights" was almost worthless. In the US they're not even allowed to describe them that way anymore. APL (talk) 16:17, 10 June 2010 (UTC)[reply]

In the US much attention was made of the government decision to allow the FDA to regulate tobacco and health claims made [3]. This [4] (subscription required) for example explains some of the problems developing 'healthier' cigarettes, for example the problem with smoking machines. Nil Einne (talk) 17:46, 10 June 2010 (UTC)[reply]

As regards APL's claim that "there is no way to make cigs safer while keeping them desirable" — that is not clear to me at all. Actually I think it may well already have been done, with e-cigarettes, which give you the nicotine without the "tar".

The current hullaballoo about them seems to be related to avoiding creating the perception that e-cigs are safe. I'm sure they're not safe. But they may very well be safer. LET ME SAY VERY CLEARLY that I am not saying they are safer — it's out of my area of expertise. But to my naive eye it appears very plausible that they might be. And if so, I think it could be a terrible mistake to try to ban them, or otherwise discourage them from the market. --Trovatore (talk) 00:35, 11 June 2010 (UTC)[reply]

Most large corporations care nothing for public health, especially not MacDonald's. ExxonMobil is another example as it promotes climate change denial. ~A H 1^(TCU) 02:54, 11 June 2010 (UTC)[reply]

By indentation, that looks like a response to me, but it doesn't appear to be responsive to anything I said. --Trovatore (talk) 02:55, 11 June 2010 (UTC)[reply]

E-cigs may or may not be safer, but they're not cigarettes. Burning some tobacco and then inhaling the smoke is pretty much the quintessential cigarette experience. What you've got here is a nicotine delivery mechanism, like a patch or a chewing gum. It's the difference between a cup of coffee and a caffeine pill!APL (talk) 03:04, 11 June 2010 (UTC)[reply]

Hmm, no, it's the difference between a cup of coffee and a hot caffeinated beverage. The e-cig still delivers something recognizably smoke-like. Or at least so I'm led to understand (I don't smoke). --Trovatore (talk) 03:10, 11 June 2010 (UTC)[reply]

I think it's more like the difference between a cup of coffee and a caffeine pill dissolved in hot water. My chain-smoking friend tried to switch to an e-cig, and said it didn't taste like a cigarette. He also had difficulty controlling the dose, and kept either not getting enough (which didn't satisfy) or getting too much at once (which left him light-headed). He switched back to cigs after a couple of weeks. 86.164.69.239 (talk) 11:36, 11 June 2010 (UTC)[reply]

Anyway, the spirit of the question was that the cigs currently on the shelf must be safe because tobacco companies don't want to kill off their customers. This is false. The tobacco companies are far more concerned about losing customers to competing brands than to the Grim Reaper. APL (talk) 14:15, 11 June 2010 (UTC)[reply]

OP here. Thank you for the clear answer, I've put a resolved tag on. For reference, the exact fallacy in my thinking had been addressed with the line "There is no way to make cigs safer while keeping them desirable. It is the smoke itself which is dangerous." So, my logic IS right, but has no applicability: yes, cigarette companies have an incentive to add a magic additive that has no affect on taste but reduces mortality. However, there doesn't (in your estimation) exist any such magic additive. I am going to reduce my smoking to 1/18th of a normal smoking level, to get to the same risk I would have if I regularly drove: I don't drive at all. 92.224.205.209 (talk) 14:22, 11 June 2010 (UTC)[reply]

nothingness

Is there a theory that states why it is impossible for nothing to exist, ether mater or energy or space? 71.100.0.241 (talk) 16:22, 10 June 2010 (UTC)[reply]

Cogito ergo sum Staecker (talk) 16:43, 10 June 2010 (UTC)[reply]

Unfortunately, that theory includes the dimension of time, which would require the thinker to live forever to be valid. 71.100.0.241 (talk) 17:10, 10 June 2010 (UTC)[reply]

I don't see any mention of time. Does existing in only a limited region of spacetime not count as existing? --Tango (talk) 17:12, 10 June 2010 (UTC)[reply]

I did not include reference to time in the question so for clarity I will include it here. 71.100.0.241 (talk) 17:21, 10 June 2010 (UTC)[reply]

There couldn't be any such theory, because any theory must start with axioms. An axiom would only be useful here if it was more basic than the fact that something exists, and what could be more basic than that? However, you might be interested in reading about the anthropic principle in relation to this. Looie496 (talk) 17:06, 10 June 2010 (UTC)[reply]

Do you mean nothing at all anywhere? ie. there being no universe? There are plenty of theories about why the universe exists, but none are really anything more than guesses. --Tango (talk) 17:12, 10 June 2010 (UTC)[reply]

Yes. 71.100.0.241 (talk) 17:17, 10 June 2010 (UTC)[reply]

If matter, energy and space did not exist, who or what could have asked the question? 87.81.230.195 (talk) 17:23, 10 June 2010 (UTC)[reply]

it never fails that when a question is asked on the Wikipedia that at least one person will respond who has not read or understood it. 71.100.0.241 (talk) 17:29, 10 June 2010 (UTC)[reply]

Perhaps, then, you could kindly elucidate ". . . ether mater . . ." for us :-). 87.81.230.195 (talk) 00:13, 11 June 2010 (UTC)[reply]

This is a philosophical question about metaphysical nihilism, not a scientific question. Scientific experiments are conducted under the assumption that observation is somehow meaningful, and it's hard to imagine observation being meaningful without at least subject to observe and an object to be observed. Paul (Stansifer) 17:47, 10 June 2010 (UTC)[reply]

You are thinking, as everyone else that because the universe exists the impossibility of nothingness can naturally be assumed. 71.100.0.241 (talk) 19:12, 10 June 2010 (UTC)[reply]

It's not an assumption, it's a fact. The universe exists, therefore the probability of the universe existing is 100%. Probability is always conditional on the information we have. Once you have definite information about something, its probability becomes 100%. --Tango (talk) 21:12, 10 June 2010 (UTC)[reply]

The fact that things exist is a very flimsy theory of the impossibility of nothingness. People remember walking in and out of the World Trade Center and some considered doing so not just theory but proof of the impossibility of nothingness in regard to the existence of the Would Trade Center. For some it continues to exist in pictures and memory but their theory of the impossibility of nothingness in regard to the Twin Towers no longer exists, especially since they were not rebuilt and most likely will not be rebuilt. 71.100.13.202 (talk) 16:46, 11 June 2010 (UTC)[reply]

Observations of the World Trade Center are proof that the WTC definitely existed at the time it was observed. Observations of the universe now are proof that the universe definitely exists now. The universe existing now and nothing existing now are mutually exclusive options, so it is also proof that there is no nothingness now. --Tango (talk) 19:15, 11 June 2010 (UTC)[reply]

It's certainly a fact that something exists. The question is, is it a necessary truth, or a contingent one? Your response doesn't address that point at all.

It's true that this is not a scientific question in a narrow sense of the word. But there isn't any philosophy refdesk, and it's closer to science than anything else. Cosmologists do worry about things not that much more concrete than this. --Trovatore (talk) 21:45, 10 June 2010 (UTC)[reply]

I wasn't making an argument for the existence of anything (though I believe things do exist -- I've seen some of them!); I was just saying that science isn't meaningful unless stuff exists. Therefore, whether anything exists is not a question science has anything to say about. Paul (Stansifer) 21:28, 10 June 2010 (UTC)[reply]

Here's how I like to think about it - take a universe where nothing exists. Now since nothing exists everywhere, the universe is completely symmetric as a sphere, thus it has a shape and consequent physical laws governing it (this is a big important consequence of Noether's Theorem). Our current scientific theory of an empty universe is instead bound by quantum mechanics. A QM universe has a dynamic equilibrium - being static and void is "more something" than being in constant turmoil as nature tries to keep any harmony from existing, this being understood a little in the Heisenberg Uncertainty Principle, where being static does not exist (you are always blurry).

So a universe in its most simple form is in utter turmoil, a churning soup of micro-energy (and in some theories, micro-wormholes). The Inflation (cosmology) scenario is that from this quantum-mechanical turmoil, there is a probability that a "metastable" state called a false vacuum appears spontaneously, with some sort of random set of physical dimensions and constants, and expands rapidly. This is the Big Bang, the beginning of our universe. SamuelRiv (talk) 17:47, 10 June 2010 (UTC)[reply]

In order for "nothing" to exist, you must have some "something" to compare it to. For example, dark is the absence of light. So "dark" is a "nothing". But suppose I claim that right now it is "foo", because of the absence of "bar". So my "foo" is a "nothing" - but actually it's not. Since "bar" does not exist, there is no absence of it called "foo". In the same way the absence of a "something" (called "nothing") can not exist without the "something". As a side note, in Jewish philosophy the very first thing God created was nothing. i.e. the concept of nothing, also called a void. Ariel. (talk) 21:09, 10 June 2010 (UTC)[reply]

This question is addressed quite well in a book called God: The Failed Hypothesis. Stenger scientifically addresses not only why there is something instead of nothing, but also the appearance of order from chaos in the universe and the issues that raises regarding apparent decrease in entropy. Vespine (talk) 23:12, 10 June 2010 (UTC)[reply]

All classical physics theory takes as axiomatic that no matter, energy or space is empty of its laws. For example, Newton's law of universal gravitation denies that even the remotest space is void of gravitational influence. Religious belief systems that predicate an omnipotent Creator must conclude that His influence pervades all that can ever be (because He wills it so). However relativistic physics provides a conception of a nothingness being that which is beyond an Event horizon. Cuddlyable3 (talk) 23:36, 10 June 2010 (UTC)[reply]

I'm not sure that is correct. For example the constancy of the speed of light still exists, even beyond the event horizon. All the various laws still exist there, there is just no information/matter there. But the "basic framework" is everywhere. Just because I am not aware of something (or even if I can not) - doesn't meant it doesn't exist. Ariel. (talk) 23:49, 10 June 2010 (UTC)[reply]

Now you're going from physics to ontology. I would disagree, for example, is the speed of light in a Gravitational singularity still equal to c? I could be mistaken but I thought that time and space formed at the big bang, so even though it might be impossible to know what was before the big bang, one theory is that there was nothing. Vespine (talk) 00:15, 11 June 2010 (UTC)[reply]

To someone falling into a singularity everything looks normal, so yes, c is the same. And anyway, changing c changes the energy content of matter (e=mc2), so you most definitely can not change c. Ariel. (talk) 00:27, 11 June 2010 (UTC)[reply]

It doesn't make sense (within our science) to talk about conditions "in" a singularity. A singularity is a point where everything breaks down - mathematically we essentially treat the point as if it doesn't exist. --Tango (talk) 00:51, 11 June 2010 (UTC)[reply]

See reality, nothing, and variable speed of light. ~A H 1^(TCU) 02:50, 11 June 2010 (UTC)[reply]

you might also check out nondualism. --Ludwigs2 04:10, 11 June 2010 (UTC)[reply]

Returning to the original question - "Can nothing exist ?" - in physics the answer is "no", because of zero-point energy; in mathematics the answer is "yes", the empty set; in philosophy the answer depends on what you mean by "nothing" and "exist" - take n philosophers and you will get n+1 answers. Gandalf61 (talk) 09:32, 11 June 2010 (UTC)[reply]

The original question is not "...can nothing exist...?" The original question is whether of not there is a theory as to the impossibility of nothingness. Quite distinct and separate questions. 71.100.13.202 (talk) 17:00, 11 June 2010 (UTC)[reply]

This is an entirely reasonable question. Until recently, there was nothing but speculation about the fate of this universe; now, its likeliest fate is that it will continue to "exist" forever, eventually reaching a state of overwhelming emptiness (lack of density), but the possibility of it one day ceasing to "exist" was still an arguable position only a few decades ago. Meanwhile, as far as we know, NOTHING EXISTED fourteen bllion years ago (though one interpretation of space-time is that it is nonsensical to refer to "time" before the big bang). The question is highly relevant in terms of (at least) cosmology (whether "nothing" is a possible state is a crucial question in regard to the pre-big-bang multiverse ... IF THERE IS ONE!). 63.17.62.133 (talk) 10:18, 11 June 2010 (UTC)[reply]

Can we have more Lay explanations for phenomena under the physics heading?

I am a poorly educated person of middling intelligence, with an interest in physics of all sort, but no head for calculus or advanced mathematics.

I would like to understand more about particle physics, but many of the explanations on Wikipedia are too complex.

I suppose what I'm asking is can we have more articles where things are explained as if to a four year old?

When I leanred about the strong, weak and electromagnetic forces, I had them explained to me using the analogy of the four forces that act on an airplane: lift, drag, thrust and weight; and this explanation, while not technically accurate, at least gave me a sense of how the forces interacted.

When I wanted to learn about magnetism, I was directed to ferrous metals, which went on and on about fermions and atomic spin and did little to explain to me what makes a metal magnetic in a practical way an unintelligent person can understand.

Thank you all for your time and I apologise if my question was inane or misplaced. AWanderingFlame (talk) 17:09, 10 June 2010 (UTC)[reply]

I don't see how that analogy to an aeroplane is at all useful. There are no connections between the two. It would be great if we could explain all these subjects to everyone, but some things are just too technical to be understood without at least some of the background knowledge. You can come up with poor analogies that trick people into thinking they understand it, but I don't really see the point of that. --Tango (talk) 17:16, 10 June 2010 (UTC)[reply]

You have a valid point, but the fact is that Wikipedia articles are written by whoever wants to write them, and explaining technical concepts in nontechnical language is the most difficult type of science writing. Whether people who can do it choose to devote their time to Wikipedia is a matter of luck. Looie496 (talk) 17:23, 10 June 2010 (UTC)[reply]

I recommend the website www.howstuffworks.com. Their mission is to provide simple but accurate explanations for all sorts of science and technology questions. (It's basically a web version of the Discovery Channel, which makes sense since they're both owned by the same media company.) --M @r ē ino 18:05, 10 June 2010 (UTC)[reply]

The question is not at all inane or misplaced; we have many, many articles that were written with a disregard for the layman. As Tango writes, it's sometimes impossible to explain sufficiently advanced topics to the layman; but I think more often it's a lack of interest on the part of the editors who are inclined to work on these articles. (It's sometimes a hard task, surely.) One suggestion I've seen on the Reference Desk here in the past is that you check the Simple English Wikipedia; here is their article on particle physics; but the objective of "Simple" is to be the encyclopedia for those with limited English-language ability, not to be the encyclopedia with simplified explanations of everything. Comet Tuttle (talk) 19:05, 10 June 2010 (UTC)[reply]

The airplane analogy is not "technically inaccurate" - it is totally and entirely wrong. It is unfortunate that somebody would use the analogy of lift and drag to describe the fundamental forces - they have only served to confuse you and provide you with incorrect information. The four fundamental forces are fundamentally different types of interactions, hence their name. See fundamental interaction. Yes, it is complicated - these things are not very intuitive. If you're looking for a qualitative introduction to the Standard Model, maybe read the overview section at Standard Model - this is much more useful than trying to understand particle physics in terms of invalid comparisons to every-day scenarios. Nimur (talk) 19:45, 10 June 2010 (UTC)[reply]

The worst are articles that are just a wall of math without a single one of the variables being defined! If you already know the material, you know what those variables are. But if you know the material you don't need the article. If you need the article you can't understand it. The articles on gauge theory were ones I noticed recently. Ariel. (talk) 21:13, 10 June 2010 (UTC)[reply]

Wikipedia has a number of introductory articles, dedicated to providing a gentle introduction to complex subjects. See WP:List of Introductory Articles. Dolphin (t) 22:55, 10 June 2010 (UTC)[reply]

It is certainly true that many of our articles on science and math subjects are written at an unnecessarily high level. I think many editors are aware of this problem and there are people actively working to improve this situation. However, some subjects (and "How do magnets work?" is certainly one of them) are simply not explicable other than by reverting to complicated explanations and math. If everything in the universe could be understood easily by the layman - then we wouldn't need physicists...and if everyone could mend broken pipes - then we wouldn't need plumbers...since pretty much everyone can write, we don't need scribes. It's just a matter of degree. SteveBaker (talk) 23:13, 10 June 2010 (UTC)[reply]

Not entirely true, maybe people who can fix pipes just don't want to be bothered with it. Just about everyone could mow their lawn, but there are still plenty of yardwork businesses. That is called the service economy. Now we just need to find someone who wants to fill the service demand for interpreting the dense science, math and engineering articles we have that are mostly equations. Googlemeister (talk) 13:14, 11 June 2010 (UTC)[reply]

I don't believe Wikipedia has any article that explains as if to a four year old, though some of the pictures might capture a child's attention. WP:NOTCENSORED implies that Wikipedia is not an encyclopedia for children. Cuddlyable3 (talk) 23:46, 10 June 2010 (UTC)[reply]

I fail to see how WP:NOTCENSORED implies that Wikipedia is not for children. It probably implies that it is not for certain kinds of Americans.

I do think that the OP has a good point though. And I think the problem is routed deeper. I believe, I could give a pretty good explanation of how magnetism works that is essentially correct as a first approximation and understandable to the OP, but I would never get it in a Wikipedia article. The problem is that my explanation is utterly unverifiable, since by necessity it would be 'wrong' in all the details. Pretty much any explanation that hinges on an analogy (like the aeroplane forces or that pretty picture of electrons orbiting an atomic nucleus) are going to be fundamentally wrong by modern understanding of physics. Is an encyclopedia simply the wrong medium for generally understandable (i.e. simplified) explanations? How do printed encyclopedias solve the problem? BTW, a good attempt at explaining science at a general audience is Bill Brysons "A short history of nearly everything". Hundreds of errors in the details, but still correct in essence and an enjoyable read.213.160.108.26 (talk) 23:42, 11 June 2010 (UTC)[reply]

Do fish get mardy?

if you poke them or something? —Preceding unsigned comment added by 86.128.193.83 (talk) 18:13, 10 June 2010 (UTC)[reply]

Assuming this is not a joke at the expense of Mr. Mardy Fish, we have a couple of articles that are sort of related. Pain in fish discusses whether fish do feel pain; one scientist is quoted as doubting that fish really feel pain in the way we do, as fish lack a neocortex. This would seem to reduce the likelihood that fish get irritable or miserable. Related is Emotion in animals, which does have a "Fish" section, though its only claims are about different fish of the same species exhibiting different "personalities" — actually, different amounts of risk taking, being "sociable", and having different eating preferences. It'll always be hard to evaluate whether animals get "mardy" because of course they can't tell us. Comet Tuttle (talk) 18:59, 10 June 2010 (UTC)[reply]

They might if you try to trawl them. Richard Avery (talk) 16:08, 11 June 2010 (UTC)[reply]

Chloroform

http://www.mangafox.com/manga/pok_mon_adventures/v32/c358/5.html

Does chloroform really work that fast? (At least, I assume that that's chloroform in the rag/handkerchief.) --75.25.103.109 (talk) 22:20, 10 June 2010 (UTC)[reply]

No it doesn't (though our chloroform article doesn't discuss the question). According to Stratmann, Linda (2003). Chloroform: The Quest for Oblivion. Sutton. ISBN 0 7509 3099 3., p.120: "The dramatic evidence of a victim was often preferred to the sober oxpertise of a medical man, who knew that up to five minutes were required to anaesthetise even a willing subject." --ColinFine (talk) 22:49, 13 June 2010 (UTC)[reply]