Wikipedia:Reference desk/Archives/Science/2010 April 29

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April 29

Albert Einstein

Who is the next genius, i meant the smartest person, after Albert Einstein's Death?75.168.119.109 (talk) 00:04, 29 April 2010 (UTC)

Tricky: My vote goes to Richard Feynman - but there are a lot of other possibilities. The problem is that the word "smart" is hard to pin down - the concept of "intelligence" and even "IQ tests" is very fuzzy - and the most intelligent people of all sometimes do very badly at those kinds of tests because they are so much smarter than the people who designed them. If you read biographies of Einstein, you tend to come away with the idea that aside from his abilities in the areas of theoretical physics - he was a complete idiot and a general pain in the ass. I don't think I would have liked him - or found him particularly interesting to talk to. Similar complaints may be raised against other possibilities such as Stephen HawkinsStephen Hawking. Personally, I respect Feynman precisely because he was brilliant (and funny and talented) in absolutely everything he approached - the sheer breadth of his talent was impressive. But I'm sure we'll have a lot of alternatives put forward. SteveBaker (talk) 00:19, 29 April 2010 (UTC)

I'm not convinced that Steve meant to link Stephen Hawkins (an Australian rower) in the above comment. Perhaps he meant Stephen Hawking (the physicist). Astronaut (talk) 01:51, 29 April 2010 (UTC)

No, no! I'm in awe of australian rowers! sorry SteveBaker (talk) 02:48, 29 April 2010 (UTC)

You mean nobody is the smartest person? I would agree with that because nobody know everything. I'm sure Albert Einstein didn't know much about other areas beside science and physic like art, genetic, biology...75.73.152.238 (talk) 00:32, 29 April 2010 (UTC)

The problem is that Einstein is not the "smartest person," he's just an icon, a popular hero. He was a smart guy and did smart things, to be sure (Many of his "big ideas" were clever; a few were downright brilliant and have stood the test of time; a few did not pan out at all and we now think he was wrong). But the popular representation of him is simultaneously exaggerated and misunderstood. (He was not doddering and out of touch with the world. He was intensely political and controversial and pushed the envelope on things like war, race, and democracy to the point that he accrued a large FBI file.) Einstein is a singular icon... there is almost nobody else like him in the 20th century, from the point of view of being the living embodiment of what it means to be a "scientist" in the popular mind. Stephen Hawkings is something of a comparison (his "iconic" status is derived in a large way from his disability in a fairly obvious way). Newton, Galileo, and Darwin served the role for earlier generations (and our own, of course). Anyway, SteveBaker's point is not that "nobody is the smartest person" but that "smartest person" is an ill-defined concept—it makes it sound like you can measure all-around smartness with one number. Nobody thinks that is case, at least not on the level of pitting individual geniuses against each other (which is not, for example, what IQ tests do). --Mr.98 (talk) 01:02, 29 April 2010 (UTC)

Right. If we had a really solid definition of "smart" we'd have a "smartest person". So maybe: "The person who is able to memorize and recite the most digits of PI" is the smartest - and currently that is a guy called Lu Chao who memorized 100,000 digits and was able to recite 65,000 digits before he mis-spoke and screwed up one digit. If you say it is the person with the highest recorded score on an IQ test then the answer is Marilyn vos Savant (who always strikes me as kinda stupid and annoying...but that's just my opinion). If it's "the person with the most Nobel prizes" then John Bardeen, Marie Curie, Linus Pauling and Frederick Sanger each have two - but Fred Sanger is the only one of them who is still alive. But which of those (or a gazillion other things I could come up with) should count? It's entirely a matter of opinion. My opinion is that being 'smart' at just one thing isn't so impressive as being good at a wide range of things - and that's why Richard Feynman gets the prize as far as I'm concerned. He only had one Nobel prize - but he also became an expert bongo player, he learned to write the Tuvan language by reading an English-Russian and a Russian-Tuvan dictionary, he was a working theoretical physicist - who became a biologist as a 'vacation', he was a self-taught safe cracker, he taught himself how to 'lucid dream', he figured out the cause of the Challenger disaster and demonstrated the problem live on TV with a $2 clamp and a glass of iced water, he learned how to pretend to be drunk and to pick up women in bars using scientific principles!...he had a life that was filled to bursting with intellectual pursuits. I think he was the "all-round" smartest guy ever...but that's just my opinion - yours will undoubtedly be different. SteveBaker (talk) 01:29, 29 April 2010 (UTC)

See, and I would actually vote for Linus Pauling. His contributions to Chemistry are as important and wide reaching as Einstein or Feynman's were to Physics. He's as close to a Chemistry Polymath as there can be; his work stretches to nearly all aspects of chemistry. Pauling's rules are central to X-ray crystalography. He formalized the concept of electronegativity and used it to explain the ionic - covalent bond continuum. He invented the concept of resonance and of delocalized electrons. He worked in biochemistry, being the among the first people to explain how hemoglobin binds oxygen. He explained the main secondary structure in proteins, the so-called "alpha helix" and "beta-pleated-sheet" models. He helped explain the molecular causes of sickle-cell anemia. He also worked on nuclear mechanics, devising his own "spheron model of the nucleus". Oh, and he also won the Nobel Peace Prize for his anti-nuclear weapons activism. I've always placed him as second after Einstein in terms of overall importance to the general scientific world. --Jayron32 01:55, 29 April 2010 (UTC)

Sure - Pauling was a god in Chemistry - but what did he do outside of that? This isn't a question about what someone achieved - it's a question about how smart they were. Knowing absolutely everything there is to know about Chemistry requires you to be pretty smart - but that's not the limit on smartness...how smart was he in his daily life? Einstein really wasn't very smart when you took away his physics. Did Pauling do smart things in his spare time? What about on vacation? What did he do for fun? Did he use all of those 'smarts' in lots of other ways? Those are all rather important to me.

My "hero" (for want of a better word) has to be good at everything he/she does - and has to do a huge variety of things - inside and outside of some narrow career path. I could come up with a long list of theoretical physics stuff that Feynman did - but he also worked to improve science and math textbooks in schools, he worked on the Manhatten project but worked to subtly subvert the military - to mock their censorship rules by doing things like writing letters to his wife in codes that they couldn't break so they had to sheepishly ask him to please tell them how to decode the letters! He achieved many breakthroughs in computing algorithms...before there were actual electromechanical computers and "computers" were people. He trained his small army of "computers" to do impressive military-style drill with their pencils on command in order to impress the generals when they came around to visit!

Pauling's biographies are mostly stuff about chemistry - a bit about his anti-nuke activisim and a bit about the sad loss of his wife and subsequent bringing up of his daughters. He's a completely two-dimensional character. Chemistry - activism - kids...the end.

SteveBaker (talk) 03:17, 29 April 2010 (UTC)

Feynman's awesomeness comes mostly from being a character. I will not attempt to diminish his awesomeness, but most of his intrigue comes from his quirky personality and his expressions thereof. I would not attempt to compare the intelligence of Feynman vs. Pauling, except that Feynman's expressions of his intelligence come off as far more entertaining which is why he gets better pub. Surely You're Joking, Mr. Feynman! is a far more entertaining read than any biography of Pauling, and much of our impressions of Feynman come from that and other books about him. I will grant you that Feynman is a far more interesting person than Pauling, but that doesn't necessarily mean he was either smarter or more important to his field or to the general advancement of knowledge. I will grant you a "tie" with Pauling on anything except "entertainment factor" which Feynman wins hands down. --Jayron32 05:14, 29 April 2010 (UTC)

Linus Pauling was of course also known for his controversial work in and advocacy of orthomolecular medicine and megavitamin therapy, particularly vitamin C, in his later years. Nil Einne (talk) 09:00, 29 April 2010 (UTC)

I nominate Raquel Welch for contributions to Paleontology and medicine. Cuddlyable3 (talk) 09:40, 29 April 2010 (UTC)

Well if you're talking about people with major achievements in more than one field, then a modern candidate would be Professor Brian Cox (physicist), who had a Number One hit in the UK in the 1990s with D:Ream (Things can only get better), went on to become an astrophysicist and work at CERN, and now is a bit of a celeb. (oh and he's a bit dishy too!) --TammyMoet (talk) 10:56, 29 April 2010 (UTC)

Brian May. --Phil Holmes (talk) 13:28, 29 April 2010 (UTC)

Intelligence is task-specific. Einstein was great at physics and math and taking a high-level view of humanity. If you want to ask about who may be exceedingly learned in some regard, you will have to specify which regard. And if you don't want to be bothered with that, if you just want some names thrown out there, I will offer singer-songwriter Mark Knopfler. An account of his humanism, and ability to express it in majestic fashion. Vranak (talk) 14:23, 29 April 2010 (UTC)

more
Why Mark Knopfler, and not for example Johnny Cash? 76.103.104.108 (talk) 06:18, 30 April 2010 (UTC) Good question! I think it comes down to lyrical and melodic elegance. Vranak (talk) So you take those things to be indications of less intelligence? --Trovatore (talk) 00:22, 1 May 2010 (UTC) This is getting silly. i.e. No. Vranak (talk)

I think we've had a good demonstration on why it's so hard to define intelligence. I can think of at least three kinds of outliers - the genius that's virtually the best in the world at a certain thing (think: Albert Einstein), the polymath that's exceptionally good at a wide array of things (think: Leonardo Da Vinci), and the teacher that can seemingly understand virtually everything and relate it to laypeople understandably (think: Isaac Asimov). Now take the first kind and multiply it by however many branches of study have ever existed. Is Stephen Hawking smarter than, say, Bach or Mozart? How could you even compare them meaningfully? Or take guys from a millennium ago like Abu Rayhan Biruni and Avicenna. How could you compare their staggering accomplishments in virtually everything to a polymath of today? Do they get credit for figuring out huge swaths of the sciences during a time when getting eaten by a bear was a realistic cause of death for people - or does someone from today get credit for reaching even further, after the "easy" stuff has been done? Matt Deres (talk) 16:42, 29 April 2010 (UTC)

Cell

I knew all cells come from cell then where the first cell come from?75.168.119.109 (talk) 00:04, 29 April 2010 (UTC)

You should read our article Abiogenesis. The short, honest answer is that we don't know for sure - but we suspect that chemicals that can copy themselves (like, maybe RNA) could come about spontaneously from random chemical reactions in the soil or the oceans - then for such molecules to become trapped inside a lipid bubble and thereby form primitive cells. But we don't know for sure. We're pretty certain it wasn't magic though. SteveBaker (talk) 00:10, 29 April 2010 (UTC)

Evolution can't explain it. --Chemicalinterest (talk) 14:55, 29 April 2010 (UTC)

Evolution doesn't attempt to explain it: evolutionary theories aim to explain how existing forms of life change over time, not how life came to exist in the first place. 87.81.230.195 (talk) 21:14, 29 April 2010 (UTC)

Aliens

I have heard and read many resources show that aliens are really exist or do not exist. Is alien really exist?75.168.119.109 (talk) 00:07, 29 April 2010 (UTC)

You're aiming for all of the difficult questions today! See our article on the Drake equation which estimates the probability that there is intelligent life on other planets - and comes to the conclusion: "Yes, there probably is". But we haven't found life anywhere - so the answer can only be "probably". On the other hand, aliens visiting Earth...No - that doesn't seem either likely or possible from the evidence we have available. SteveBaker (talk) 00:12, 29 April 2010 (UTC)

I think the aliens have came to Earth before at least one time. If not then how could you explain all the UFO we have seen from the ancient time until today.75.168.119.109 (talk) 00:23, 29 April 2010 (UTC)

I don't explain "all of the UFO's" - there is not one single reliable sighting of such a thing. The ideas put around by "UFOlogists" are just typical 'nut job' stuff - packed full of unlikely conspiracy theories and unreliable "eye witness" testimony. The idea that a small craft could cross hundreds of lightyears and somehow hide from us for 60 years while still revealing itself in conveniently unconvincing ways to individual humans in the numbers they claim...it's not remotely credible. The idea that governments are 'covering up' the evidence is crazy - the government are completely inept at covering things up. Go to a UFO conference sometime (I did...once!) and the people there who claim to have been visited or abducted are the least convincing people you'll ever meet - their stories fall apart once you start asking careful questions - they are liars, one and all - mostly, they seem to be people who have had nothing interesting happen in their lives who have come up with this story to make themselves seem different, interesting, important. It's just sad. SteveBaker (talk) 01:54, 29 April 2010 (UTC)

Actually, Steve, UFO's really do exist on Earth -- just not the alien kind. See List of experimental aircraft, Skunk Works, Nellis Air Force Base, and Edwards Air Force Base for more details. :-) 76.103.104.108 (talk) 02:33, 29 April 2010 (UTC)

I don't think all of the people who said they have seen the aliens are all liars. There must be at least one of them say the truth. And also in ancient time there are some UFO were written by historian, i don't think their purpose is lying to us.75.168.119.109 (talk) 22:46, 29 April 2010 (UTC)

I expect very few UFO sightings are lies. Most of them are simply mistakes. --Tango (talk) 06:15, 30 April 2010 (UTC)

Those probably aren't the kind of UFO spotters that travel the country telling their story. "I Saw a mysterious red dot in the sky." just isn't interesting or special enough. APL (talk) 04:07, 1 May 2010 (UTC)

Yea I agree but there must be one is the real aliens. Maybe by some reasons the aliens didn't want to contact us yet. I think there are some aliens visited us on 20th century after maybe a hundred years travel in the space and they have some kind of machine to make them not getting older so as long as they sleep in that machine they will not die. I think they didn't try to contact us yet because they saw the World War 2 were happening and they also want to come back their planet to inform to their planet that they found alien, us, and to prepare the next travel to Earth. If this is right then we have to wait like about 100 more years to see aliens come back to Earth again.75.168.119.109 (talk) 22:17, 30 April 2010 (UTC)

I wonder why aliens never try to contact us. Does anyone know?75.73.152.238 (talk) 00:32, 29 April 2010 (UTC)

Most aliens keep a low profile, because even if they are here legitimately, the Arizona police will stop them and demand their papers. Nimur (talk) 08:26, 29 April 2010 (UTC)

I agree with Steve! Just because YOU can't explain something, doesn't mean Aliens did it. As to why they haven't tried to contact us, well maybe they have but we missed it? One of the difficulties is the vast amount of empty space and time involved. I believe it is extremely likely there would be intelligent life somewhere else in the universe, but it might be a million years ago, or a million light years away, or billion, or any combination of the two. In any case, there's no real way to know, let alone communicate anything meaningful. Vespine (talk) 01:44, 29 April 2010 (UTC)

The universe is very, very empty, but it is also very very big. There are billions of galaxies, each containing billions of stars. A large proportion of those stars probably have planets. Using the Drake Equation it is easy to calculate there are probably other planets with intelligent life - quite possibly millions of planets. Because eveything is so far away that even light takes years to travel between the stars, it is unlikely that aliens would be able to make the journey to visit Earth, or for us to make the journey to visit them. Using current technology, it would take many thousands of years to travel to the nearest stars (see Voyager 2#Escaping the solar system and Voyager 1#Current activities for estimates of when these NASA probes could reach interstellar distances). Astronaut (talk) 01:46, 29 April 2010 (UTC)

Perhaps they do - but if they are out there - they are hundreds of light-years away. If you put the most powerful radio transmitter mankind has ever made on a planet orbiting the nearest star to us - then our most sensitive radio telescope would be unable to detect it. So unless these aliens have vastly more powerful transmitters than we do (or unless they know that we're here and can use a laser or something) - then we stand no chance of hearing them. Because the only way they could "know we're here" is if they can detect the signs of civilization in our atmosphere or something - and those changes only proceed outwards at the speed of light - they would have to be pretty close to us in order to have time to notice that we're here. Furthermore - their idea of "clear communications" might be very different from ours. We're expecting something like a sequence of prime numbers, transmitted in binary on a frequency near the "hydrogen hole" - but it might come in the form of choreography instructions for interpretive dance steps designed for creatures with eleven hooves and nine tentacles transmitted using 'spread spectrum' techniques. They might well be blasting us with copies of "The Encyclopedia Galactica" and "Welcome to the space-faring species club!" messages - and we'd never know it. SteveBaker (talk) 01:54, 29 April 2010 (UTC)

Also, aliens may not use electromagnetic radiation to communicate. For some alternative possibilities, see here and here. Count Iblis (talk) 02:05, 29 April 2010 (UTC)

There are many more possibilities - how about aliens who live long lives - but who's brains work v-e-r-y s-l-o-w-l-y. Suppose they sent their messages by radio or light at a rate of one bit per month or something. Would we notice such incredibly low frequency messages? Or suppose they were incredibly patient and sent messages by changing the chemical composition of immense gas clouds around some star or other - expecting us to decode the spectral characteristics resulting from that? If you consider all of the ways we could imagine they might communicate - and then realise that there are just about guaranteed to be a bunch of other ways we couldn't imagine...it's easy to see how we haven't heard anything as a result of the SETI work. A darker possibility is that there are dangerous races of aliens out there and all of the others realize that the risk of broadcasting their position is simply too great. Maybe they just aren't particularly talkative - it could easily be that this desire to communicate is a uniquely human characteristic. Maybe their technology just took off in a different direction and they never bothered much with astronomy or even physics in general? Until or unless we find something 'out there' we simply cannot know why we aren't. SteveBaker (talk) 03:33, 29 April 2010 (UTC)

The Fermi paradox discusses these reasons. CS Miller (talk) 12:49, 29 April 2010 (UTC)

You know, if I were an alien species with super-duper technology, and I wanted to make other intelligent beings know I existed, then I would make a star blink. Create a giant movable star-shade and send out ultra low-frequency bits (showing primes or whatever). That would give you enormous power, a broadband signal, and a wide viewing angle. And of course, a flickering star would be easily noticed with even the level of technology available to stupid apes like us. Dragons flight (talk) 07:08, 29 April 2010 (UTC)

"Create a giant star-shade" Hmm?!! —Preceding unsigned comment added by 86.4.186.107 (talk) 07:48, 29 April 2010 (UTC)

Very good, and there's me thinking we were discovering hundreds of exoplanets, and all it was was some alien race putting on a light show with morse-code. How disheartening.... :) --KägeTorä - (影虎) (TALK) 12:11, 29 April 2010 (UTC)

That's not a bad idea. It is probably centuries beyond our technology, though (the usual caveats about any technological prediction beyond 25 years apply). The shade would have to be planet sized to result in a noticeable dimming to our best current telescopes. It would have to be star sized to noticeable to the naked eye. --Tango (talk) 14:10, 29 April 2010 (UTC)

I think if an alien intelligence wants to send a detailed message then some kind of mathematical signal sent using EM is by far the most likely. The aliens will go through the same thought process as us and try to work out what is likely to be in common between technological species and they are likely to come to the same conclusion we did - mathematics. If they are intelligent enough to be sending messages to other species then they are likely to be intelligent enough not to assume all intelligent species have the same number of legs they do. EM is the most likely medium because the only other option is gravity and that is much harder work (due to elementary particles having much greater charges than they do masses, in natural units). One thing we should keep in mind is that they may not be trying to send a detailed message but just something that unambiguously says "We are here". In that case they don't need mathematics, just anything unnatural. Changing the spectra of nebulae could do that. They may think it is easier to do something like that and look for responses so they can send their detailed messages to a specific target. --Tango (talk) 14:10, 29 April 2010 (UTC)

One possible explanation for the lack of alien contact may be that aliens don't think it is worth it. Travelling between stars takes a long time (aliens could have longer lifespans than us, but they aren't likely to be much longer since that would tend to slow down evolution, so they wouldn't have reached intelligence yet - of course, I'm extrapolating from a single data point, so the margin of error is rather large!), so they may well assume they will never actually meet any aliens and will just be communicating with a round-trip time of decades or centuries. Such slow communication won't allow for much information to be exchanged, so the practical benefit is likely to be minimal. --Tango (talk) 14:10, 29 April 2010 (UTC)

They could be completely different from humans in a way that no one ever dreamed of. There is no evidence either way. --Chemicalinterest (talk) 15:06, 29 April 2010 (UTC)

I agree, but we can still make educated guesses based on the basic principle that a notion of "technologically more advanced" should correpond to "being able to utilize resources to achieve more objectives". Then I think that since we are all machines, but that in biological form we don't have much control over our lives, more advanced civilizations will be machine civilizations. Space travel is far more practicical if you are an electronic machine because then you can just upload yourself to a machine on the place of destination via radio communications.

You can then also imagine that civilizations repeatedly transmit radio messages that contain details on how to build their hardware, followed by messages containing their software. Such messages can be picked up long after the civilization is gone, billions of years later, by another civilization who could decide to build the machines and then download the aliens into the machines. Count Iblis (talk) 15:55, 29 April 2010 (UTC)

If we have absolutely nothing in common with them, then we'll never be able to communicate with them (or perhaps even recognise them) anyway, so we might as well assume we do have something in common with them. The something is the technology necessary to send and receive messages between stars. There are different ways of doing that, but it doesn't seem likely (and I'm only talking about likelihoods, I'm not ruling out anything as impossible) that they could be built without mathematics. --Tango (talk) 16:18, 29 April 2010 (UTC)

The Drake equation makes sense, it is just that for most of the variables going into this equation we could be off by orders of magnitude and not realize it since our observations of extrasolar items smaller then stars is extremely limited and prone to observation bias. Googlemeister (talk) 20:03, 29 April 2010 (UTC)

I don't think all of the people who said they have seen the aliens are all liars. There must be at least one of them say the truth. And also in ancient time there are some UFO were written by historian, i don't think their purpose is lying to us.75.168.119.109 (talk) 22:46, 29 April 2010 (UTC)

You're assuming that all speakers have perfect knowledge. Far more likely that some are lying, whereas others are mistaken and telling the truth about their subjective experience. Since we do know of phenomena which lead to exactly the experiences reported by the majority of 'abductees', see particularly parasomnia, it would be odd to assume they were, instead, abducted by aliens of which we have no other evidence. Alien abduction has a good overview of the basics. 86.178.225.111 (talk) 18:54, 1 May 2010 (UTC)

Hmm, sorry I see the parasomnia article is somewhat lacking. Try sleep paralysis for more detail. 86.178.225.111 (talk) 19:04, 1 May 2010 (UTC)

A couple thoughts on why, if aliens exist and are able to communicate with us, they might choose not to:

1) The noninterference directive. That is, they want our civilization to develop (or maybe destroy itself), without influence from them. This could either be because they think it's immoral to interfere or because they view our development as a science experiment, and they don't want to bias the results.

2) There may have been a vicious galactic war, and the few survivors only manage to stay alive by keeping hidden/quiet. Perhaps reruns of Gilligan's Island are headed to the evil aliens even now, who will then find us and wipe us out as a potential future threat. (Somehow I always knew that show would bring about our destruction. :-) ) StuRat (talk) 19:17, 1 May 2010 (UTC)

Personally, StuRat, I think you've been reading too much H.G. Wells. :-) 67.170.215.166 (talk) 03:45, 2 May 2010 (UTC)

God

There are many religions in the world. Is god really exist? Or big bang.75.73.152.238 (talk) 00:35, 29 April 2010 (UTC)

If god does exist then who create god? —Preceding unsigned comment added by 75.73.152.238 (talk) 00:42, 29 April 2010 (UTC)

Start with God and then move onto Big bang. People here might tell you that science does not deal with questions regarding God, but there are people who would disagree. For a scientific treatment of God you could try reading God: The Failed Hypothesis by Victor Stenger, I've just started reading it myself. No prizes for guessing Vic's stance on the subject ;) . Vespine (talk) 01:19, 29 April 2010 (UTC)

You have to take it on faith that (the christian interpretation of) god has always existed and was therefore never created. On the other hand, there is reasonably compelling scientific evidence that the big bang occurred around 13.7 billion years ago. Astronaut (talk) 01:18, 29 April 2010 (UTC)

God and the Big Bang are not mutually exclusive concepts; there is nothing that prevents a person from understanding the implications of the Big Bang and also believing in God. To understand how philosphers have long tried to reconcile these ideas in a more formal way, you may want to read Primum movens and Unmoved mover and Cosmological argument. The notion of a God who exists before creation (whatever the nature of that creation may be) has been pondered since the time of Aristotle. --Jayron32 01:43, 29 April 2010 (UTC)

And these concepts have been disproven long ago. At the end of the day the unmoved mover cannot be questioned, because there's no answer there. Imagine Reason (talk) 13:52, 29 April 2010 (UTC)

Where did the material from the Big Bang come from? It requires just as much faith to believe that it came from nothing as to believe that God created it. --Chemicalinterest (talk) 15:30, 29 April 2010 (UTC)

It takes no faith, but perhaps some courage, to say simply: "I don't know." Dragons flight (talk) 18:39, 29 April 2010 (UTC)

But it is simpler to say "The universe appeared from nowhere." than "God appeared from nowhere and created the universe". They both require the same amount of unexplained appearance, but one involves an extra entity. (See Occam's razor.) --Tango (talk) 19:05, 29 April 2010 (UTC)

One does not involve an extra entity; both require that something was there already. In science, things cannot appear. That's why origins is not science; its philosophy, regardless whether somebody doesn't like philosophers. I believe that God was always there, even though it is difficult to comprehend. --Chemicalinterest (talk) 19:15, 29 April 2010 (UTC)

One involves the universe. The other involves the universe and god. That is an extra entity that is not required, which is why it is not included in scientific theories. --Tango (talk) 18:48, 1 May 2010 (UTC)

'Where did the material from the Big Bang come from?' (Supposedly,) A singularity - a zero dimensional object with infinite density and zero volume. --Joe^Talk_Work 13:36, 3 May 2010 (UTC)

We have pretty good evidence for the Big bang now (See: Cosmic microwave background radiation, for example) - so it's pretty much certain that it happened. God is the opposite. Zero proof - zip, nada. Worse still, the descriptions of god (or gods, plural) that people come up with seem carefully thought out so as to make the hypothesis that god(s) exist "unfalsifiable". This is a serious matter in science - if a hypothesis cannot (even in principle) be proven to be false - then we generally discount it. The proponents of gods claim that god can do absolutely anything and has no restrictions on his/her/its' behavior whatever - and (worse still) that he actively works to deceive us (in order to "test our loyalty"). So scientists say "Hey - look at all those fossil dinosaurs! We can test them with radioactive dating techniques they are a bazillion years old! We must be right about evolution and that whole Noah's ark and Garden of Eden story is definitely false!"...and the religious folks say "No, the Earth is 6000 years old. God put the fossils in there - and deliberately created the right amount of radioactivity in them to 'test your faith'...you have no faith! Hahahahaha!". If you're happy to take that shit on trust - then there is nothing science can do to 'falsify' that. There is no possible experiment we could do that the religious nuts can't just turn around and say "Gotcha! Proved you don't have faith!". It all seems kinda childish actually - but that's how it is.

Some atheists have created 'fake' religions - The Invisible Pink Unicorn (mhhbb) is a popular one. The point being that there is quite literally nothing to say that the god of the christians or the jews or the muslims is any more or less real than the IPU (pbuh). Anything that suggests that the IPU (whans) isn't real or shouldn't be worshipped (for example, by eating ham & pineapple pizza - She is not a particularly demanding God) can easily be dismissed by using the exact same arguments that the 'real' religions use. They'll say "but our religion has been around for two thousand years - God has been worshipped for millennia" - and the response is that the universe was created last Thursday and all those old churches and gorgeous pieces of music were created by Her to test the faith of the righteous. They don't have a leg to stand on.

The scientific answer is: "There is nothing whatever out there that even hints at the possibility that there are gods out there."...the hypothesis that there is some kind of divine presence is unfalsifiable and Occam's razor says we should ignore all of that stuff. Russell's teapot bears reading.

SteveBaker (talk) 02:42, 29 April 2010 (UTC)

There is evidence for a God; it just depends on one's prejudice, whether they ignore the facts or not. --Chemicalinterest (talk) 19:19, 29 April 2010 (UTC)

It's a category error to try to apply science to things that don't admit direct observation. (Now, it is possible to just reject all things that can't be scientifically observed; logical positivism does that. It's a very simple philosophy that rejects the existence of all of the fun things philosophers talk about: ethics, qualia, souls, God, etc. Our article explains why most philosophers don't do that.)

This all is to say that the science reference desk can't help you with this question. Since a metaphysics reference desk doesn't (and can't) exist, all we can do is point you to the Existence of God article. Paul (Stansifer) 03:10, 29 April 2010 (UTC)

Oh nonsense! Science is successfully applied to all sorts of things that we can only deduce indirectly - quantum theory, string theory, dark matter, dark energy, neutrinos...many, MANY things! Religious types wish science would just leave them alone and decide that religion is outside the scope of study - but that's not gonna happen. (Besides, philosophers are a waste of quarks! Their function in the universe is to hasten its end by accelerating entropy - taking in ordered information and producing hot air.) SteveBaker (talk) 03:53, 29 April 2010 (UTC)

False religion, which as I said in Cheminterest's talk page, is just another method of controlling people (as are dictatorships). True religion accepts science, knowing that it will never contradict God's word. False religion is disproved by science; true religion is supported. --Chemicalinterest (talk) 19:21, 29 April 2010 (UTC)

Steve the first bit is right but the second an absurd generalisation. Sure Stupid types wish science would just leave them alone and decide that they could hang on to any superstitious or religious beliefs (tried telling an old lady she is silly to believe her horoscope?) but I see no evidence that more stupid people are religious than are not. It may be true of course especially in the US where the default belief set might be religious it does not seem to be in most of Western Europe, where the no thought>>no religion (not the converse, of course). But I think there should be an absolute prohibition on people discussing the existence of God before they can demonstrating their grasp of the much more straightforward question of whether a scientific test can be devised for the existence of people, will science ever see beyond the atoms and cells? --BozMo talk 07:42, 29 April 2010 (UTC)

There is evidence that less intelligent people are more religious. See Religiosity and intelligence. Whether the evidence is conclusive or not, I will leave to you to decide (the main difficulty is quantifying intelligence in a meaningful way). --Tango (talk) 14:22, 29 April 2010 (UTC)

It does not mean that more intelligent people are less religious; it is just that people who think themselves more intelligent are less religious. --Chemicalinterest (talk) 19:17, 29 April 2010 (UTC)

Not seen that before but as you can imagine it is pretty weak, First, "religiosity" not religiousness(the former apparently means superstitiousness) and of course the fact it is all tgs data (which as I mentioned is the obvious case). There are good reasons to believe less intelligent people are less likely to question the prevaling beliefs where they are. But no visible evidence beyond that, and some counter data (e.g. religious expression by Mensa members if ever you wanted a contrived selection of clever people... --BozMo talk 18:21, 29 April 2010 (UTC)

There was a US study published this year (I think) claiming to find a statistically significant difference of ~7 IQ points between Americans who attend church weekly and those who attend never or only a few times a year. Of course, even if the difference is statistically significant, 7 points is too small to be of any practical impact with individual cases. Undoubtedly there are nonetheless many smart religious people and many dumb atheists. Dragons flight (talk) 18:33, 29 April 2010 (UTC)

The true God wants man to use his full brain power. Some people may think otherwise, but God isn't a crutch (to lean on instead of using your God-given abilities), he is an assistance (to enhance your abilities and help you when you try to think over some problem). --Chemicalinterest (talk) 19:25, 29 April 2010 (UTC)

Neutrinos are observable; it's just that the experiments that you need to run on them are very expensive and long. We can't experiment on goodness at all. (You can experiment on what people think about goodness, but that's not nearly as important a problem.) The only way to approach it is through philosophy. It may not be that rigorous, but it's the only thing we've got! Paul (Stansifer) 09:45, 29 April 2010 (UTC)

Careful there... It's a common mistake, but people very commonly misunderstand the concept of religion, and assume that we all blindly reject science for our religions. It is my belief, as a Christian (and I am NOT trying to tell people what to believe, this is only my belief as a supporting example) that God created the Universe the way it is, along with all of the science. I believe that it is billions of years old, and that humans are evolved. I am unabashedly Christian, a "proponent of God", and I can certainly say that Steve Baker's understanding of religion only applies to certain groups. Religion and science are not inherently exclusive. I already accept science without any hesitation, but some scientists seem incapable of allowing for the unknown, which makes me question their motives of even positing theories. Falconus^{p t c} 12:02, 29 April 2010 (UTC)

Humans don't need redemption or salvation in the theory of evolution. Imagine Reason (talk) 14:01, 29 April 2010 (UTC)

Falcon, if you accept the laws of physics then the God you speak of is a God of the gaps. We don't need to use the god-hypothesis to explain any phenomena that we've observed because the laws of physics explain everything. In this case, all outcomes are simply the result of previous outcomes (plus a bit of randomness perhaps) so all God did was to press the big red button that says "start big bang" and then he just walked away - in this belief system, prayer is futile. 196.38.62.178 (talk) 15:14, 29 April 2010 (UTC)

That;s not necessarily so. The "God of the Gaps" explanation purports that people assume that all unexplained phenomena are proscribed to God, and that when the unexplained becomes explainable, God is somehow "removed" from the equation. Falcon's philosophy seems to mirror mine very closely, and I can tell you its a very different understanding of God (at least for me, I won't speak for him). I have no doubt that God exists, and yet I also have no desire to explain the as-yet-unexplained phenomenon as "miraculous" or "from God". I fully expect that all observable events and the basic laws of how the universe works are perfectly describably by science. I don't expect to find God in any of the gaps. Instead, I find that God serves a purpose in human experience in that God helps define those things, such as purpose and morality and the like, which science is incapable of describing. Science can describe how I got here, but it does a terrible job of describing for what purpose am I here. For many people, "we are here for absolutely no purpose" is a fine conclusion, but that conclusion is as unsupported by anything scientific. It is equally as valid as "We are here for God's purposes, he gives us our purpose" insofar as neither statement has any evidence which supports or refutes it. Another way to look at it: No matter how detailed we get in describing God's creation, such detail in no way denies the Creator. I can study the details of my TV and know exactly how every component came to be and the chemical composition and organization of every single bit in it; I can understand the processes that brought it into being, but none of that denies that my TV was made by something. The TV was built by someone for a purpose, and did not become a TV by random chance. Describing the laws of the universe is much the same for religious scientists. No aspect of understanding God's creation is off-limits, but no level of detail in describing that creation denies the existance of the creator. I am not so arrogant that I think I should tell God how he should work. If he works through the laws of physics so be it. If his plan to create me was evolution than so be it. I accept God as he is, insofar as my observational skills can understand him. --Jayron32 18:26, 29 April 2010 (UTC)

Wow, Jayron. We both posted very similar perspectives, about 3 minutes apart (see below). Well done, sir. Kingsfold (talk) 18:35, 29 April 2010 (UTC)

IP 196 logged in Jayron, two quick comments. If you expect that all observable events are described (or describable) by science, how can God perform miracles (i.e. answer prayers)? Surely He would have to violate the laws of physics if he were to intervene on Earth - i.e. all events are a function of previous events and the laws of physics (assuming determinism, but this argument still applies if things are non-deterministic) so either A)God will have to break the laws of physics to change things, or B)God set out his grand plan at the begining and everything is unfolding exactly as he wanted including people worshipping and praying to Him. There is no point to praying under B and A can't be true if things are describable by science. Second comment: Occam's razor says "We are here for no purpose" is preferable to "We are here for God's purposes". Zain Ebrahim (talk) 21:41, 29 April 2010 (UTC)

First comment: That's not necessarily true -- many miracles described in the Bible would not actually require God to break the laws of physics, but only to apply a sufficiently large amount of energy, of the right kind, in the right place, at the right time. To illustrate what I mean: Suppose there is some person on some big battlefield somewhere, hunkering down in his foxhole under intense artillery bombardment, and praying for God to protect him. Suppose further that God has some special reason to protect that particular doughboy from harm, because this person plays some important role in His plan. Further suppose that God sees that the enemy has just fired, or about to fire, a big shell that will kill the aforementioned doughboy if allowed to follow its own ballistic trajectory. Finally suppose that He decides to protect this special doughboy by subtly altering (directly or indirectly) the atmospheric pressure/temperature distribution of the atmosphere in the immediate area of the battlefield in order to set up a high-altitude wind shear that would cause the shell to miss its target point and explode harmlessly in an empty area of the battlefield. What laws of physics can you name that would categorically prevent the scenario I just described?

Second comment: "We are here for no purpose" is a thoroughly despicable position from an ethical and sociological point of view, because it encourages apathy (thus discouraging people from working for the betterment of their nation) and moral laxity (which abets all kinds of self-destructive tendencies within society, like drug abuse, unchecked promiscuity, etc.) For this reason, "We are here for God's purposes" is preferable to "We are here for no purpose", absolutely regardless of Occam's razor or any such philosophical shenanigans. Occam's razor (and the scientific process in general) is intended to explain how the world around us works, and NOT what our own purpose in this world is. The first is the proper domain of science, the second is the proper domain of philosophy, ethics and (in some philosophical systems) religion. 76.103.104.108 (talk) 06:57, 30 April 2010 (UTC)

We make our own purpose. Imagine Daniel Dennett's survival machine, which is made to keep us alive under stasis for centuries. If the machine becomes self-conscious, it will make its own purpose, regardless of what we programmed into it. Thus even if the bible is correct, we humans, once self-conscious, do not serve the god's purpose anymore. 67.243.7.245 (talk) 14:00, 30 April 2010 (UTC)

That is, unless He has already foreseen the purpose that each one of us chooses to serve (and personally, I don't see no reason why He wouldn't have that ability).76.103.104.108 (talk) 01:39, 1 May 2010 (UTC)

76, First comment: the laws of physics don't allow for a God to change things as He pleases. Initial conditions plus physical laws determine future events - so if God wants to change future events, he'll have to change the physical laws (assuming determinism). Second comment: Maybe I should have been clear about what I meant by "preferable" - I meant "a more likely statement". Ethics, apathy, laxity and whatnot are irrelevant to the discussion of whether we have a purpose or not. All of those things say that it might be nice if we had a purpose but they don't provide any evidence that we do. 196.38.62.178 (talk) 14:23, 30 April 2010 (UTC)

"Initial conditions + physical laws determine future events", you say? That would mean that every future event is already predetermined by initial conditions and can't be changed by anyone's free will, and this makes absolutely no sense. If this was true, then it would mean, for example, that if you were driving on the turnpike and you saw someone in the middle of the road, you would have no control over whether or not you hit that person -- which is demonstrably false from everyday experience. (Incidentally, it actually supports the idea that some theologians support [but I strongly reject] that when God created the world, He predetermined all future events by determining the world's initial conditions; but this is beside the point.) The truth is, each one of us can influence future events through our own free will, by applying the right amount of energy in the right manner at the right time (for example, in the scenario I just mentioned, by applying about 10 pounds-force of kinetic energy to your car's brake pedal); and if each one of us has the ability to influence future events by applying energy to objects around us, why wouldn't God have the same ability on a bigger scale? 76.103.104.108 (talk) 01:55, 1 May 2010 (UTC)

Most every assertion about God that you could come across tends to unravel into ribbons of illogic flapping silently in the breeze, once put under close scrutiny. But logical rigour is not what religion is about. It is about social control. I will admit that it is not a bad ideology under some circumstances. So to answer your question -- yes God has substance and reality, insomuch as there are definite and concrete forms that the concept takes within the human psyche. Apart from that though, no, plainly God does not manifest itself in the world. God is the world, a theologian might tell you. Vranak (talk) 14:19, 29 April 2010 (UTC)

Please allow me to offer another perspective. Please also understand that I write not to preach or to assert, but to simply provide what I feel is a sufficient explanation for my belief system. I realize and completely understand that for many people, belief in a higher power is illogical and unproveable. However, my belief isn't founded in intellectual logic or proof-- it's founded in faith.

It has been stated above that there is absolutely no evidence that God exists, but depending on where you lie on the continuum of what to accept as proof, from as little as the beautiful and complex perfection of the Charonia tritonis to as much as God Himself descending from a sky accompanied by concourses of angels; anything and everything could be accepted as proof. I would also suggest that the most steadfast non-believers would probably not accept even a personal visit as proof… In other words, “absence of evidence is not evidence of absence.”

I feel like I can both accept science AND believe in God because for me, science answers the “what,” while my beliefs answer the “why.” For me, science can’t begin to answer the reasons for our existence, or where our spirits go when we die. Admittedly, those that don’t believe will assert that there is no greater reason for our existence, and we aren’t headed anywhere. That’s OK for them, but I suppose I need to understand for myself.

For me, God actually knew the science of what he was creating, used it, and doesn’t go around saying, “Hey—I’m God! I did that!” (Would we believe Him if He did? Probably not.) I believe that He initiated the Big Bang, wistfully aware that many of his children would not see his omniscience behind the science. I’ll probably draw fire from both sides on this one, but I don’t believe either the ex nihilo principle, or the literalist principle that the Earth was created around 6000 years ago. In my belief set, the dinosaur question can be answered by the principle that God organized already-existing materials into the earth that we live on. As such, this could mean either that dinosaurs existed on older planets and were within fragments used to create this earth, or that God can manipulate our understanding and measure of time, and the dinosaurs existed here on this earth but were extinct before Adam was created. It may just be remotely possible that God knew that our imperfect civilizations would one day rely (for better or worse) on fossil fuels, and made them available for just that purpose.

I also am not compelled to believe that God, as we know Him, has always existed. Realizing that this is somewhat “deep water,” spiritually speaking, I would suggest that God learned to do what he is now doing in a process of self-perfection. He, then, was created by His God, who was created by His God, who was created by His God, etc., etc., etc. For many, this will smack of blasphemy and polytheism; neither of which I intend. I worship my God, or in other words, the God that corresponds to my sphere of existence. This may kind of boggle the mind a little bit, but I simply keep the First Commandment… or at least I try to.

I also don’t believe, as was asserted, that God can do absolutely anything and has no restrictions. He operates under natural laws, many of which we may just be unaware of. He also has the so-called “restriction,” of not being able to suspend free will. He cannot force me to believe in Him or obey His commandments. I act as my own agent, but I am also bound to accept the eternal consequences of those actions.4

So to sum up—while I believe in God, I hope that I don’t come across as an illogical religious zealot, because I’m not. I just feel like I’ve found a system that accommodates both science and religion, and that offers the best explanations on the reasons for them. Thanks much! Kingsfold (talk) 18:29, 29 April 2010 (UTC)

That's pretty much what I said (which is what you said). Also consider the following analogy. Lets say you are an engineer designing some system to do something. A big machine that does something really important. Who's the better engineer: The one that designs a machine that needs constant maintaince, such that the engineer has to show up every few days to make it work; that requires constant input to get the right results, or the one that designs a machine that just needs to be turned on and runs smoothly and does what it is supposed to do with very little tending. Seems to me that the better engineer is the one that designs a well-made machine that needs very little interference. Which kind of engineer is God? To me, its OK for God to be a good engineer, who designs a system that runs smoothly in His absence. I don't need him to be a bad engineer whose system needs constant maintenance. He can still show up once in a while to make sure everything does run smoothly. But he doesn't have to... --Jayron32 19:01, 29 April 2010 (UTC)

God enjoys watching what he makes. He likes to communicate and be friends with people on earth. --Chemicalinterest (talk) 19:52, 29 April 2010 (UTC)

@Jayron32 and Kingsfold. You've both mentioned (explicitly or implicitly) that science answers the hows, while religion has provided answers to the whys for you. As a very firm non-believer, I'm curious which "why" questions religion has answered for you and what the answers were. Again speaking only for myself, as you have done, I wouldn't see any reason to accept why answers from a source that's gotten virtually every single how question wrong it's ever tried to answer, so I suppose my third question would be why would you make the decision to do that. Matt Deres (talk) 20:30, 29 April 2010 (UTC)

Sure Matt Deres. Here are some of the questions religion has answered for me, that science has been unable to:

• What is expected of me as a human, in terms of how I am to interact with other humans.
• What is expected of me in relation to my creator; that is having created me, how does he expect to relate with me
• The expectation that life has a purpose, even if I may never know that purpose. For me, living a meaningful life means that I am here for a reason, knowing that the creator has a reason, even if I am incapable of understanding it.
• Knowing that there is more to my existance than the short time I am "alive", and also knowing that my time being alive is special and not to be wasted, since it will effect what happens after death.
• Knowing that there is a path to atone for all of the mistakes I have made, and that there is an end to the cycle of guilt for those mistakes.

I actually find it quite suprising that many people don't, at some point, think about the purpose of their lives. I have been an athiest for a sizable part of my life, and I found that the greater sense of purpose, and the sense of well-being knowing that there is a plan, was what was missing from my life at the time. --Jayron32 21:07, 29 April 2010 (UTC)

True religion and science complement each other. One helps the other. False religion may prevent scientific discoveries. Life is purposeless without God. As the Bible puts it, "We may eat, drink, and be merry; for tomorrow we die." When people know God in their lives, it gives them a purpose. They are here to bring others on the right path. BTW, some people find their atheist beliefs comforting because they can understand science. People cannot always understand God, which makes them uncomfortable because of their pride. That is why true religion humbles you. You are not infallible. --Chemicalinterest (talk) 00:13, 30 April 2010 (UTC)

I'm not surprised you find such beliefs comforting. Many people take comfort and strength from religion. However, I am curious that you say you were an atheist for many years. If you don't mind my imposing on you further, I wonder if you could explain what changed to make a scientifically inclined atheist believe in God, and an afterlife, and a divine plan, etc.? Dragons flight

(talk) 21:42, 29 April 2010 (UTC)

What makes atheism science, and God religion? Both are religions, one glorifying man's reason, and the other glorifying a Supreme Being. --Chemicalinterest (talk) 00:15, 30 April 2010 (UTC)

Don't want to be a party pooper, not that I don't find this kind of stuff personally interesting, but this has long ago ceased being a ref desk topic and turned into a general opinion debate. If you want to continue maybe you can take it to aa user page or something? Vespine (talk) 22:22, 29 April 2010 (UTC)

The problem is: people make many more opinions about God and religion than they do about mercury I and II ions, which will necessarily make the discussion much bigger. As I said earlier, feel free to use my talk page too. --Chemicalinterest (talk) 00:22, 30 April 2010 (UTC)

No Vespine, you're not being a part pooper; you're correct (though I guess that doesn't preclude to also being a party pooper!). Anyway, my apologies for my part in the shift away from references. Jayron, I've learned quite a bit about various topics from you on these pages over the years. If you'd care to continue the conversation off-board, my email works. If not, then I thank you for your indulgence here. Matt Deres (talk) 22:36, 29 April 2010 (UTC)

This conversation seems is not going to end. you could argue forever whether god is exist or not because nobody could prove god is exist. Same as big bang. I think the big bang theory is make more sense because god could not just come from no where and has superpower to create Earth. Perhaps big bang is the one who create god then god create us. Conclusion: Nobody knows for sure what actually happen at the beginning of the universe whether god or big bang create the universe. By the way, just for you guys know English is my second language and I'm not fluent on it yet. Therefore my English grammar is bad.75.168.119.109 (talk) 22:31, 29 April 2010 (UTC)

The Big Bang could just as easily have come from nowhere and created the world as God came from nowhere and created the world. Time seems to make the ludicrous seem more scientific. If someone said that an explosion happened and H2 and O2 changed into amoebas in one second, fish in another, horses in another, and man in four seconds, people would laugh you away. But eons of time makes it seem much more appealing to others. Its a subtle strategy. --Chemicalinterest (talk) 00:22, 30 April 2010 (UTC)

Actually, whether god exist or not. It doesn't matter. we, humans, still humans whether god exist or not. God doesn't do anything impact to us anyway. But we, humans, alway curious about everything around us. We alway want the correct and make sense answer. I believe one day someone will find out the true but at least several more hundreds years.75.168.119.109 (talk) 23:07, 29 April 2010 (UTC)

How do you know that God does not do anything to impact you? You might have just never experienced life without God (e.g. in hell). --Chemicalinterest (talk) 00:22, 30 April 2010 (UTC)

Because i don't see anything that god impact human.75.168.119.109 (talk) 01:35, 30 April 2010 (UTC)

I also think as humans become more advance technology the less people believe in god. An example: Before 18th century most people believe in god because they could not explain anything in the life. The only thing they could think is someone has superpower do all of them. In 20th century, as we become much more advance the people believe in god continue to reduce more. At my parents time, in school, they teach about evolution and the creation of god but today, they get rid of the creation of god already.75.168.119.109 (talk) 23:36, 29 April 2010 (UTC)

Actually they used to attribute more things to spooks, magic, ghosts, and the devil than God, like St. Elmo's fire and lightning. --Chemicalinterest (talk) 11:37, 30 April 2010 (UTC)

They trust in their technology rather than in God. That does not mean that God is not real; it is just that people are becoming proud of their achievements and would rather be independent. Thinking that they are responsible for all of their actions to someone who created them is too restricting. --Chemicalinterest (talk) 00:22, 30 April 2010 (UTC)

LOL! Less people believe in god because the more we are advance the more we find out that a lot of things aren't doing by god as we thought.75.168.119.109 (talk) 01:23, 30 April 2010 (UTC)

A lot of great responses here. I have a lot I could say, but I don't really feel the need to, because others have covered my sentiments well. Falconus^{p t c} 04:44, 30 April 2010 (UTC)

Which way do they lie? Everyone has their own subtle differences. --Chemicalinterest (talk) 11:37, 30 April 2010 (UTC)

That both faith and science can exist together without issues. Indeed faith and science compliment each other. Falconus^{p t c} 12:36, 30 April 2010 (UTC)

Yes. They never contradict each other, if the faith is true. --Chemicalinterest (talk) 16:41, 30 April 2010 (UTC)

Science has found that humans die like other animals, and nothing but molecules live on. It has also found that humans evolved for no particular reason but that we tend to have survived better. We are not special, and this troubles religious people. You can continue to claim the god of the gaps, but that is not one of the bible. 67.243.7.245 (talk) 14:02, 30 April 2010 (UTC)

Consider these points, from a friend who is a biologist and is religious:

1. Regarding dinosaur bones being faked by God to test faith: "God does not deceive."

2. Regarding evolution: "Evolution is how God works."

My additional thought: Substitute "Nature" for "God" and that covers it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:50, 30 April 2010 (UTC)

religion and science could never be friend because their belief is always arguing to each other. There must be one right whether it is science or religion. We just don't know yet but i think as our tech. keep getting better. One day we will find out the answer for this junk of mystery. The only reason religion still exist is it already made root in many people minds for thousands of years. And unexplainable things because whenever scientist could not explain anything the religious people will say: god did it. By the way, i want to ask some question about god.

If god is a creator of the universe then he could do whatever he wants to the universe like we could do whatever we want to our stuffs, which are created by us. Then why didn't him show up his power to humans then we, humans, will believe in god. He didn't do anything to make people to believe. All i saw is there are some extreme religious people claimed themselves as the prophets sent by god and come to show us their faith by being the martyrs, if someone ask: why would they die for their faith, that's probably god's power. Maybe they are just crazy and extremely believe in what they have learned from their parents, religion teachers... He could send people to make humans believe in god why didn't he do it by himself. Isn't god too lazy? I think Jesus is a man who knows a lot of tricks and miracle, as a lot of people called god's power, and he wants to be famous and becomes god. His death is great right but could not compare to how many people have die to follow religion. Many people have die even more painful way than the way god die. I think at some point in human history, there must be something has happened to started to make humans to believe in god. Maybe gods are actually aliens. If i could come back 2000 years ago and bring all the technology we have now. It's just easy to make people think i'm god. This book would be an good example to who actually god is: behold the man. I think another possible way to explain about god is. In future when we invented time machine and when scientist found out and prove there is no god. More and more people deny to believe in god. In the despair of losing faith, there is a man who extremely believe in god. He tries to come back in time and bring real Jesus to this time so Jesus could save his religion. But after he traveled back to time, he stuck here then he thought god want him to play a role of Jesus to started Christianity then he did it. I hope those who are religious people don't get mad at me.75.168.119.109 (talk) 22:51, 30 April 2010 (UTC)

What do you mean, "he didn't do anything to make people believe"? Don't the Ten Plagues of Egypt count as "doing something"? 76.103.104.108 (talk) 02:00, 1 May 2010 (UTC)

A reference? On the reference desk? Since I got bored reading people insist that other people didn't really think what they said they thought, endlessly cycling without listening to the replies. 86.178.225.111 (talk) 18:33, 1 May 2010 (UTC)

Black hole

What inside the black hole?75.73.152.238 (talk) 00:42, 29 April 2010 (UTC)

Gravitational singularity, you might also find our Black hole article interesting. Vespine (talk) 01:13, 29 April 2010 (UTC)

"The black hole?" Which black hole do you mean? Astronaut (talk) 01:11, 29 April 2010 (UTC)

It is (technically) impossible to ever know what's inside a black hole because nothing (not even information) can escape from the hole. All we know about it is its mass, it's electrical charge and whether it's spinning or not...but what's inside the 'black' event horizon is literally impossible to know. Because the black hole is made of ordinary matter that's gotten so massive that the very atoms that it's made of are crushed by the pressure - it seems likely that the material keeps collapsing until it's an infinitesimal 'dot'. This dot would soon have literally zero size - a "singularity". But because we can't examine the physics of what happens to matter when it's crushed to that crazy extent, we can't EVER know for sure. SteveBaker (talk) 02:04, 29 April 2010 (UTC)

It's not actually known if information can escape a black hole, see Thorne–Hawking–Preskill bet. Ariel. (talk) 05:01, 29 April 2010 (UTC)

We know is that there is a ball of great mass in the center of the black hole with a radius less then the event horizon. I do not think there is a way to definitively determine whether the ball is an infinitesimally sized sphere, or a house sized sphere, or for large black holes, even a planet sized sphere, but we do know that it is incredibly dense. Googlemeister (talk) 19:07, 29 April 2010 (UTC)

To be a bit snarky, it isn't clear whether it is possible to find out what's inside a black hole (many physicists don't believe there would really be a singularity), but whatever the answer is, you wouldn't be able to tell anybody outside about it. Looie496 (talk) 21:12, 29 April 2010 (UTC)

Wormhole

Have we found any of wormhole? does wormhole really allow time travel?75.73.152.238 (talk) 00:46, 29 April 2010 (UTC)

No. Wormholes are theorised to exist, but none have yet been discovered. Parts of the same theory predict that an object falling into a wormhole might travel in time, as well as in space. Astronaut (talk) 01:06, 29 April 2010 (UTC)

Wormholes are just theoretical - we've never found one - we might never find one. However, that was true about black holes until we started finding them - and now they've gone from "unlikely theory" to "definite fact", to "found in the center of every galaxy" and now to "fundamentally important to the formation of galaxies"...so there is still hope for wormholes! However, the time-travel thing is MUCH more tricky. It's not really enough for wormholes to exist - we'd need to be able to create them, move them around - enlarge them - and even then, the odds are very good that the whole thing would turn out to have a horrible snag. So I'd put the odds of Wormholes existing at maybe one in ten (gut feel) - and the chances of them being usable for time-travel as one in a trillion...I strongly believe that the laws of physics will conspire to make time travel (into the past) impossible. SteveBaker (talk) 02:16, 29 April 2010 (UTC)

About blackholes found in the center of galaxies - do they know it's a black hole specifically, or just a super massive object? But not necessarily a black hole with all it's strange properties. Ariel. (talk) 02:45, 29 April 2010 (UTC)

Well, the one at the centre of the Milky Way is the mass of 3.7 million Suns and occupies a small volume. See Supermassive black hole and Schwarzschild radius#Supermassive black hole for more info. Astronaut (talk) 03:01, 29 April 2010 (UTC)

Yep we know it's a black hole. Anything with that much mass and that little volume has enough density to crush itself down to a singularity - it's way too big to become a neutron star - so yep, it's the real McCoy alright. Schwarzschild radius, Event horizon, Devourer of Worlds, singularity, australian-rower-radiation, spaghettification, The Whole Shebang. SteveBaker (talk) 03:42, 29 April 2010 (UTC)

That's actually circular reasoning. The assumption is that a large mass will become a black hole (due to the math). Then you find a large mass, assume it's a black hole, and prove the theory is correct. Perhaps there is something currently unknown that prevents the mass from fully collapsing? That's basically what I was asking, is there evidence that the mass actually collapsed? Because until there is such evidence I would hold off on saying black holes were found. To flesh out what I was saying, let's assume (for no reason at all) that quark degeneracy pressure is infinite. Could our current observations distinguish such an object from a true black hole? Ariel. (talk) 04:52, 29 April 2010 (UTC)

That assumption violates causality, but I get your point. It's just not a very good one. Everything we observe is interpreted within theoretical understanding. Dauto (talk) 04:56, 29 April 2010 (UTC)

I know everything is interpreted within theoretical understanding, I just wanted to know if there was evidence for a black hole, or if we are still working with theoretical models. Why would it violate causality? Ariel. (talk) 05:04, 29 April 2010 (UTC)

Even before the discovery of real life black holes, no theoretician worth their salt would have placed black holes and worm holes in the same bag of goods. the former is an almost unavoidable consequence of the collapse of very massive objects while the later is more of a theoretical chimera that likely doesn't exist at all. Dauto (talk) 04:56, 29 April 2010 (UTC)

Titration curve: help!

Let's say we have a solution of HCl of known volume and concentration, being titrated by NaOH of known concentration. I want to know what the pH is after x mL of NaOH have been added. According to my book, we can assume that all the OH in NaOH react completely with all the H+ in HCl and neutralize. The obvious problem is, what happens near the equilibrium point? Following the textbook's logic, all the H+ in the solution would eventually react with OH- and disappear, which is obviously impossible because that would make the equilibrium point have a pH of infinity instead of 7. So, how would I calculate pH's near the equilibrium point? --99.237.234.104 (talk) 00:48, 29 April 2010 (UTC)

It hardly "disappears". It turns into H2O, which has a pH of 7. 69.210.129.248 (talk) 01:17, 29 April 2010 (UTC)

H2O doesn't have a pH of seven; pure H2O self-ionizes into H+ and OH-, and the H+ cause the water to have a pH of 7. --99.237.234.104 (talk) 01:27, 29 April 2010 (UTC)

It does have a pH of 7; the ionization does not affect the pH because the OH- causes the water to have a pH just as much as the H+. --Chemicalinterest (talk) 19:29, 29 April 2010 (UTC)

(edit conflict)To explain a bit better. Under all conditions, all water solution obey the equilbrium of the autoionization of water. In all conditions, the equilibrium constant for this reaction, Kw = [H3O¹⁺] * [OH^1-] = 1.00 x 10^-14. That is because at 25^oC, the reaction goes to the point where [H3O¹⁺] = [OH^1-] = 1.00 x 10^-7 M . Since pH = -log [H3O¹⁺], pH of neutral water = 7. Now, since the expression Kw = [H3O¹⁺] * [OH^1-] must always be true, if we change the value of either [H3O¹⁺] or [OH^1-], the value of the other one must change in the opposite direction. So, if you add [OH^1-], the [H3O¹⁺] drops by however much is needed to keep [H3O¹⁺] * [OH^1-] = 1.00 x 10^-14. The article pH also discusses this some. --Jayron32 01:33, 29 April 2010 (UTC)

I know the basics, so although I'm grateful that you tried to help, your post wasn't very useful. I was asking how you find the pH of a solution that's being titrated when the solution is near, but not at, the equilibrium point. --99.237.234.104 (talk) 02:24, 29 April 2010 (UTC)

pH meter? --Jayron32 02:34, 29 April 2010 (UTC)

He's trying to find it theoretically. You would assume that your acid and base react completely, and then use whatever you have left (either a small amount of acid or a small amount of base) as the starting concentrations in an ICE table for the autoionization of water: H₂O → H⁺ + OH^-.

That's exactly the method suggested by the textbook. As I noted in the question, this doesn't work if the amount of NaOH added is exactly the same as the quantity of HCl in the beaker. In that case, your method would suggest there would be no H+ left in the solution, which is not possible. Intuitively I suspect your method breaks down close to the equilibrium point, not just exactly at the equilibrium point, but I'm not sure about that. --99.237.234.104 (talk) 03:04, 29 April 2010 (UTC)

The ICE table works fine. Use the expression Kw = [H+] * [OH-]. If there is zero added H+ or OH-, this still works fine, since 1 x 10^-14 = Kw, and if there is no added H+ or OH-, you know that, because of the autoionization of water reaction, you can use the stoichiometric relationships in that reaction to prove that [H+] = [OH-]. If that is the case then [H+] = [OH-] = SQRT (Kw) = 1 x 10^-7. If you have a SMALL amount of added H+ (i.e. within an order of magnitude of the amount in neutral water), then you can assume that [H+](eq) = [H+](Init) + [H+](added) and simply recalculate [OH-] from the Kw expression; and visa versa. --Jayron32 03:12, 29 April 2010 (UTC)

You have to know the number of moles per liter of H+ and OH- ions. Subtract the OH- from the H+ because a certain amount of OH- was added, and calculate the pH using the negative logarithm of the moles per liter of H+ to find the pH. --Chemicalinterest (talk) 19:31, 29 April 2010 (UTC)

conductivity of crumpled aluminum foil

I seem to have forgotten my basic MSE ... does work hardening increase or decrease the conductivity of a material? I know you dope semiconductors with foreign atoms ... but this is effectively a form of hardening by encouraging defects, right? John Riemann Soong (talk) 04:50, 29 April 2010 (UTC)

I think it decreases slightly due to dislocations impeding the flow of electrons, but this effect is negligible compared to other factors like temperature. FWiW 76.103.104.108 (talk) 05:29, 29 April 2010 (UTC)

Wrong. See Doping (semiconductor). Doping increases the number of available carriers, and therefore reduces the resisitivity. Putting defects into a semiconductor typically increases resisitivity. --Phil Holmes (talk) 13:20, 29 April 2010 (UTC)

Oh hmm... now I remember... there is a tradeoff right? Doping increases hardening, so if you dope too much you end up decreasing conductivity overall, so there is an "optimum". John Riemann Soong (talk) 15:03, 29 April 2010 (UTC)

Broadly speaking, doping a semiconductor has no effect on its hardness. In the normal range of dopant concentrations (which are in between very low and low in everyday terms) doping has a linear relationship with resistivity - see http://cleanroom.byu.edu/ResistivityCal.phtml for example. At very high levels of dopant, it's possible that the semiconductor becomes degenerate and so adding extra dopant adds no further carriers. However, the extra impurities would reduce the carrier mobility so the resistivity would increase. I can't currently find a reference for this actually happening, though. --Phil Holmes (talk) 16:12, 29 April 2010 (UTC)

I'm pretty sure I remember seeing a graph for that in my MSE class. Conductivity increases then decreases with increasing dopant concentration. John Riemann Soong (talk) 05:08, 30 April 2010 (UTC)

As I said - if this does happen, it would only be at very high dopant levels - higher than are normally employed in semiconductor manufacture. --Phil Holmes (talk) 08:22, 30 April 2010 (UTC)

Hmm, yes, now that I remember, the x-axis (dopant concentration) was plotted logarithmically... but it seems someone did experiment with this (rather than this being based on any industrial data). Perhaps the dopant levels in industry are set this way precisely to avoid conductivity issues? John Riemann Soong (talk) 12:51, 30 April 2010 (UTC)

I can't remember well off the top of my head, but I believe the dopant was a p-type and conductivity started decreasing around 10^-6 to 10^-5 molar... if I remember correctly. John Riemann Soong (talk) 13:51, 30 April 2010 (UTC)

No. That's roughly 1e17cm-3, which is pretty low doping. I think you may be thinking of mobility, not conductivity. This decreases with increasing doping owing to carrier scattering at the dopant sites. Conductivity is a function of mobility and carrier concentration, but since carrier concentration increases way faster than mobility decreases, conductivity still decreases with increasing dopant levels at this dopant level. Boron is the only commercially used p-dopant with silicon. --Phil Holmes (talk) 14:40, 30 April 2010 (UTC)

Reactivity series for anions

I know the Reactivity series for metals, but is there any such list for anions (such as NO₃^-, SO₄^2-, Cl^-, etc.)? Thanks in advance, --The High Fin Sperm Whale 05:16, 29 April 2010 (UTC)

Exactly what kind of reactivity are you talking about? 76.103.104.108 (talk) 05:31, 29 April 2010 (UTC)

If you meant reactivity in redox reactions, then yes, there is such a list, but it's called a table of standard reduction potentials. Clear skies to you 76.103.104.108 (talk) 05:36, 29 April 2010 (UTC)

See Standard electrode potential (data page) for a complete list. The activity series is basically derived from the Standard reduction potential data; you get it by pulling the metals out of the list, and ignoring the numbers. Before chemistry students are introduced to electrochemistry and redox it is a way to predict the likelyhood of a single replacement reaction occuring, as identifying the products of basic chemical reactions is taught several months before electrochemistry is. Once you have learned basic redox stuff, the activity series is moot. --Jayron32 18:13, 29 April 2010 (UTC)

I also was looking for the activity series for anions, but I didn't come up with very reliable results. One thing I have found is that metal ions lower on the activity series tend to take the conjugate base of the weaker acid. In other words, the metal ions higher on the activity series take the anions that come from stronger acids. HCl is stronger than H₂O. OH^- is the conjugate base of H₂O, and Cl^- is the conjugate base of HCl. NaOH will react with CuCl₂ to take the stronger acid's conjugate base Cl^-, giving CuCl₂ the weaker acid's conjugate base OH^-. This may vary, though. --Chemicalinterest (talk) 19:36, 29 April 2010 (UTC)

Actually, you are completely mistaken about the NaOH and CuCl₂ reaction. The reaction is a simple precipitation reaction. Neither "NaOH" nor "CuCl₂" exist in solution. Both are strong electrolytes, meaning that they dissociate 100% in water. So if you have a solution of NaOH, you actually have a solution that has equal parts Na¹⁺ and OH^1- ions. Likewise, a solution of CuCl₂ has one part Cu²⁺ ions and two parts Cl^1- ions. When you mix the solutions, the Cu²⁺ ions from the second solution clump together with the OH^1- ions from the first solution (they are now in the same batch of water) and the clumps stick together and sink to the bottom. The reason the clumps form can be explained electrostatically or thermodynamically, but solubility rules provide a nice list of how to predict what sorts of ions are incompatibile in solution with each other. The Na¹⁺ and Cl^1- ions don't do a darned thing. They are floating in water before the reaction, and they are floating in the water after the reaction. The net reaction when you mix sodium hydroxide and copper(II) chloride is:

• Cu²⁺ + 2 OH^1- --> Cu(OH)₂

There are further reactions that can occur if the OH^1- is in enough excess. Complex ions like Cu(OH)₄^2- can form as well. The reaction between copper and hydroxide, to form both the precipitate and the complex ion, is best explained by Lewis acid-base theory. --Jayron32 20:53, 29 April 2010 (UTC)

What makes the Cu++ and the OH- ions bond? The forces between the anions and cations. I measure those forces by my rule: Ions of a more reactive metal tend to react with anions of stronger acids. The NaCl does theoretically form, because the other ions are evacuated.--Chemicalinterest (talk) 00:04, 30 April 2010 (UTC)

NaCl does not form. There are no discrete particles of NaCl in the solution. There are only sodium ions and chloride ions. Saying it exists does not make it so. It just doesn't exist as discrete particles. You cannot find a single "NaCl" moety in the water solution, so its a pointless distinction. There is no reaction, they are spectator ions pure and simple. The Cu++ and OH- form bonds because the ion-ion interaction is more favorable from a gibbs free energy standpoint than the ion-water interaction. --Jayron32 02:59, 30 April 2010 (UTC)

dietary fiber supplements such as methycellulose and inulin. What is each of these, and what is the difference between the two?

Having bought both, I called the makers, who explained they were fiber derived from plants/vegetables but they were unable to tell me what the difference between them is or why one might be easier to digest then the other. The labels indicate, however, that you need to take a lesser quantity of inulin than methylcellulose for same result. Can you explain the difference? —Preceding unsigned comment added by 71.51.75.185 (talk) 06:21, 29 April 2010 (UTC)

Do you mean Methyl cellulose? We have an article about Methyl cellulose as well as about inulin. I am not personally familiar with those dietary supplements, and I cannot offer any help or advice. Sorry. --Dr Dima (talk) 07:25, 29 April 2010 (UTC)

Neither can be digested, by you, that is. Inulin and methylcellulose are both dietary fibres, and as such, are not metabolized by the human body. Inulin, however, can be metabolized by intestinal flora and promotes their growth. It can also have positive affects on kidney function. Which one is better for you is something you could discuss with your doctor or nutritionist. Someguy1221 (talk) 07:37, 29 April 2010 (UTC)

Eagles and their Wings

Eagles unlike other birds do not flap its wings often (mostly). How do they fly so high and for a longer time? I presume that it flies higher flapping the wings and just descends down with no wing movement, searching for a prey. Let me be clarified. - anandh, chennai —Preceding unsigned comment added by 125.21.50.214 (talk) 06:45, 29 April 2010 (UTC)

We have an article on Bird flight. If you still have questions after reading it and following links, please ask. --Dr Dima (talk) 07:10, 29 April 2010 (UTC)

Thanks. gliding (flight) is also informative. Do all predators (birds) show flight movements like eagles? —Preceding unsigned comment added by 125.21.50.214 (talk) 09:12, 29 April 2010

It's not just the predators. Few things are more beautiful than watching a kettle of turkey vultures soaring a thermal. --jpgordon^{::==( o )} 16:08, 29 April 2010 (UTC)

Turkey vultures? They aren't normally considered beautiful. Should I edit your comment???... --Chemicalinterest (talk) 19:37, 29 April 2010 (UTC)

If you can watch what I've just described and not find beauty, I feel deeply sorry for you. --jpgordon^{::==( o )} 01:04, 30 April 2010 (UTC)

Turkey vultures are very graceful in flight, indeed. Quite common, too, so easy to observe. --Dr Dima (talk) 07:49, 30 April 2010 (UTC)

Living and Non-living

How are we (creatures) differentiated from inanimate objects when everything in this world is of chemicals (elements, atoms, molecules or compounds)? Is that like we have active components, being recycled in search of stability, supporting the entropy of the universe, reactions with delta E negative etc., etc.,? If so, why don't inanimate objects have this sort of happenings (nevertheless, the entropy of the universe is positive anyways)? I am not sure if am clear, hope you get the question(s). - anandh, chennai. —Preceding unsigned comment added by 125.21.50.214 (talk) 06:59, 29 April 2010 (UTC)

Life#Biology is a good place to start reading. --Dr Dima (talk) 07:19, 29 April 2010 (UTC)

Cogito ergo sum. How about you? Cuddlyable3 (talk) 09:18, 29 April 2010 (UTC)

Would that work for AI? 67.243.7.245 (talk) 13:55, 30 April 2010 (UTC)

How do I know you aren't just an artificial intelligence with an IP address? See Turing test. Cuddlyable3 (talk) 22:07, 1 May 2010 (UTC)

I think therefore I am. The question is why can't inanimate objects think? (they don't think and therefore they are not?, but WHY "they don't" and what in us makes us to "think" is what i wish to know) - anandh, chennai —Preceding unsigned comment added by 125.21.50.214 (talk) 09:42, 29 April 2010 (UTC)

Keep in mind that it's cogito ergo sum, not cogito igitur sum. That is, my cognition proves my existence, because nothing that does not exist can think. There is no suggestion that my thought is the cause of my existence, or a necessary condition for my existence. (Actually I'm not sure at all that ergo and igitur are used distinctively in this way, but I am sure that this is what Descartes meant.) --Trovatore (talk) 18:13, 29 April 2010 (UTC)

How do you know they don't think? --TammyMoet (talk) 10:50, 29 April 2010 (UTC)

As a sidebar from a humanities person, this is sometimes taken as evidence of a higher being. I am not endorsing or refuting this view on this reference desk, and I don't particularly want to start a massive debate; since it is a fairly common explanation even to today among large groups of people, I felt it worth mentioning, despite the lack of scientific evidence. That is all, Falconus^{p t c} 11:49, 29 April 2010 (UTC)

I think you should avoid the cogito ergo sum approach. That barely works with humans (if it does) and certainly can't be extrapolated to all living creatures (and not even to all humans). The article Dr Dima linked to has a more generalizable description of how we define things and why it gets tricky in border cases.

As for understanding why animate objects exist: if you start with very complicated organisms (humans, for example), it looks endlessly miraculous. Start small and build up. Bacteria and viruses are a bit more easy to understand, and what makes them "alive" or "dead" or "neither" (in the case of viruses) is easier to see. Then realize that every cell of in a multi-cellular organism meets the criteria for "life", and that we are a very complicated amalgamation of many types of specialized cells all working together. (Then wonder where our sense of consciousness and individuality comes from out of all of this mass of cells.) --Mr.98 (talk) 12:55, 29 April 2010 (UTC)

The border between living and nonliving isn't a bright line. It gets quite fuzzy. You first have to consider whether you are talking about individual living things or about Life as a system (i.e. the entirety of the biosphere or all of living things taken together) Consider things like viruses and prions. Are they alive? Depends on how you define life. Is a virus alive when it is isolated on a petri dish? What about when it is actively infecting a cell? Could viruses exist outside of Life as a system? Could viruses have come to exist outside of Life as a system? Do viruses do anything we expect an organism to do? There's some stuff which is unquestionably alive (like me). There's other stuff which is unquestionably not (like say, a chunk of granite). Things just get a bit fuzzy at some of the border conditions. --Jayron32 18:56, 29 April 2010 (UTC)

Ancient pagan religions considered everything to be alive, i.e. to have a "spirit" associated with it, yes? And even now we anthropomorphize storms, bodies of water, the earth itself. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:39, 30 April 2010 (UTC)

Gas and Gravity

Why are not gases influenced by gravity? - anandh, chennai. —Preceding unsigned comment added by 125.21.50.214 (talk) 07:07, 29 April 2010 (UTC)

They are influenced by gravity, of course. If they were not, the atmosphere of the Earth would have escaped into space almost immediately. --Dr Dima (talk) 07:15, 29 April 2010 (UTC)

Perhaps you are asking, "If gas is influenced by gravity, why doesn't it all fall to the surface of the Earth?" Mm? It's a good question. And I can answer it with another question: "Why don't your feet sink into the ground?" Obviously, because the ground is solid, and it pushes back on your feet. Now, we all know that gas is not solid. But have you ever tried squeezing a balloon? Even though gas is not solid, it does push back when you try to compress it. And that's why air stays "up". Earth's gravity does pull it down, but air resists from being compressed infinitely. Someguy1221 (talk) 07:22, 29 April 2010 (UTC)

Atmospheric escape might be a good article to read in order to understand the role of gravity. A Balloon (aircraft) also, requires the action of gravity on gases in order to obtain its buoyancy.--Aspro (talk) 07:58, 29 April 2010 (UTC)

Thanks. But i think the explanation with gas compression is paradoxical when degree of randomness is considered. —Preceding unsigned comment added by 125.21.50.214 (talk) 08:09, 29 April 2010 (UTC)

OK, how about this. Let's go to extremes, the gas Sulphur Hexafluoride is heavy enough to float a boat (sort of), as can be seen here in this demo. [1]. Just think about how much you could support with Uranium Hexafluoride! --Aspro (talk) 08:35, 29 April 2010 (UTC)

Gas molecules do fall to the surface of the Earth, but then they bounce up again. The reason they never lose all their energy to friction and settle down is that the surface of the Earth is vibrating (because it's warm). It's not obvious to us but it's very obvious to the gas molecules with their very tiny masses. There's a nice mechanical model of this at the Exploratorium in San Francisco—here's a photo of it. The molecules also bounce off of each other, but that's not essential. You can pretend that each molecule moves independently, bouncing off the ground over and over, and get basically the right physical predictions (this is the ideal gas approximation). -- BenRG (talk) 09:14, 29 April 2010 (UTC)

Thanks. Warm air (or hot land surface in this case) expands gases and so it is above. Obviously because of warm air, gases raise and tend to be in a region where it is not influenced (means, concentrated there) but below that region, the concentration is less. Fine, to what extent the effectiveness of warm air is...to keep the gases from moving to a region with lower concentration? —Preceding unsigned comment added by 125.21.50.214 (talk) 09:31, 29 April 2010 (UTC)

Each parcel of gas is attracted to the Earth's gravity, but it is also repelled by the pressure of the gas below (which is minutely greater than the pressure of the gas above.) The end result is that the forces on each parcel of air are in equilibrium. (If we imagine too much gas moving closer to the Earth we must also imagine the pressure gradient increasing too, and that would drive the excess gas upwards again, to restore the equilibrium.) Dolphin (t) 13:15, 29 April 2010 (UTC)

See hydrostatic equilibrium. You can actually model this using a computer program. Model a bunch of bouncing balls under a constant force of gravity, but make all the collisions elastic (i.e. flip all the vector components the opposite sign when it hits a wall or another ball). You'll get a distribution of balls heaviest near the bottom and light near the top. Interestingly, that's what the atmosphere behaves like...

The reason why we don't behave like air molecules is that generally our collisions with the ground are not so elastic. But if every time we jumped we didn't lose any kinetic energy, we would behave like gas molecules. John Riemann Soong (talk) 15:10, 29 April 2010 (UTC)

Alarm clock

My wife and I each have an alarm clock on our nightstands. They are not identical, but both are of the common type that has a red LED display, plugs into the wall outlet, and has a 9 volt battery for backup during power failures. They're probably both 10–15 years old. Yesterday there was a power failure while we were at work. I don't know how long it lasted, but no more than ~8 hours and probably less. After the power failure, both alarm clocks were ahead of the correct time by 10–20 minutes. This is, of course, horrible accuracy compared to even the cheapest wristwatch. Why are these alarm clocks so inaccurate when running on battery? -- Coneslayer (talk) 11:05, 29 April 2010 (UTC)

When running on alternating current, the frequency of the supply provides an accurate source of information, and the clock is designed to make use of that information. When running on battery the clock has an alternative mechanism for keeping track of time, probably some sort of resonant circuit. It seems the mechanism for time-keeping on battery is simple and inexpensive, and remarkably inaccurate. The designer of the clock was presumably of the view that the battery would only be required for relatively short periods, and designed the resonant circuit accordingly. Dolphin (t) 13:09, 29 April 2010 (UTC)

I knew that analog wall clocks often used the AC frequency for timekeeping, but didn't realize that digital clocks did as well. Is it possible that the frequency of the DC circuit has a dependence on the battery voltage? After all, the voltage of an alkaline battery varies considerably over its useful life. -- Coneslayer (talk) 13:25, 29 April 2010 (UTC)

I had one which allowed you to switch between 50hz and 60hz before. Have you ever looked closely at your clock and/or the manual if you still have it do see if yours does? Nil Einne (talk) 06:57, 30 April 2010 (UTC)

Very intersting. I would've expected the clocks to be BEHIND the real time. --Kvasir (talk) 16:24, 29 April 2010 (UTC)

Since I didn't notice the discrepancy until I was early for work this morning, I'm glad they were ahead. -- Coneslayer (talk) 16:28, 29 April 2010 (UTC)

Maybe the quartz crystals were defective. --Chemicalinterest (talk) 19:39, 29 April 2010 (UTC)

It may be by design. If you know the backup you're designing is generally going to be inaccurate it makes sense to make it so it's normally faster rather then slower when one of the likely intentions is to keep an alarm, for obvious reasons. Nil Einne (talk) 06:55, 30 April 2010 (UTC)

Since even a $5 wristwatch runs much more accurately than that, it's probably just that the manufacturer used the cheapest timing circuit they could find, figuring that it would very rarely come into play. Looie496 (talk) 21:05, 29 April 2010 (UTC)

$5? I actually saw a wristwatch for $1 plus tax in a dollar store. Everything in it was a dollar. --Chemicalinterest (talk) 00:40, 30 April 2010 (UTC)

Just as a point of information, this is something that varies (or has varied) from one brand so another. There are three alarm-clock-radios in my house with digital time displays and battery backup: a Toshiba, an Optimus, and a Sony Dream Machine. The first two behave in the way the original poster describes. But the Sony's designer evidently felt differently about this issue. When the power goes off and comes back on, the display starts flashing so you're warned it might not be accurate. And, ironically, it's also much more accurate than the other two in this situation. Of course, that might not apply to this year's equivalent model. --Anonymous, <blink>01:02</> UTC, April 30, 20, 10.

These refs [2] [3] suggests it a common issue, they usually use a cheap and crap RC oscillator for the purpose. Nil Einne (talk) 06:50, 30 April 2010 (UTC)

Quartz crystal oscillators usually have a Q factor on the order of 10 x 10⁶, or one part in ten million error (this one is 10 parts in 1 million, but still darned good). So, if the clock is losing or gaining minutes on the day, it's clearly not using a quartz oscillator; I'd assume such a clock keeps time with a poorly tuned RC oscillator whose accuracy is under-engineered for cost-reduction. It's probable that it uses a separate clock for its backup than it does for its powered, normal operation - probably because "backup" was tacked on as a feature. Again, the OP's assertion is totally correct - it could be designed to operate entirely on battery and use the power only to drive the LED lights and alarm speaker, and therefore the accuracy would not change when power goes out. It probably uses a "sloppy" design to save costs or use up stock components in a manufacturer's warehouse. Nimur (talk) 14:50, 30 April 2010 (UTC)

Nimur, when talking about the frequency accuracy of clock oscillators you should not call that their Q factor. Q factor as the article explains defines the resonator damping, not its long-term accuracy. Cuddlyable3 (talk) 22:02, 1 May 2010 (UTC)

What? Crystal_oscillator#Electrical_oscillators. Damping is directly related to frequency stability. Undamped oscillators have infinite Q and would be an ideal simple harmonic oscillator. Real oscillators have a frequency spread because they are dissipating energy. Crystal oscillators are normally characterized by their Q and their center-frequency. If our articles aren't sufficient, I can point you to about 29,000 Google Scholar hits for quartz oscillator q factor. It is standard engineering parlance to use Q factors to describe frequency stability. Nimur (talk) 06:38, 2 May 2010 (UTC)

How to Identify nylon 6 from nylon 6,6?

I was wondering if anyone knew of a way to tell the difference between nylon 6 and nylon 6,6? This information would be useful to help me recycle the nylon with more efficiency. Thank-you for your time. —Preceding unsigned comment added by 70.229.42.54 (talk) 12:46, 29 April 2010 (UTC)

In the lab one can use a rather large spectroscope machine and look for their respective signatures. On that basis, I did a search and found there is now a hand-held Fourier transform infra-red spectroscopy unit that will do the same thing. No idea how much it is though. No doubt the same technique could be used to automatically sort wast on a conveyor belt. Here's the instrument[4] and here is a PDF in which the claims that it can do these two Nylons is specifically made [5] --Aspro (talk) 13:47, 29 April 2010 (UTC)

I actually already have an IR machine unfortunately this only lets you know that you are dealing with nylon and not what kind of nylon. are there any other tests that can be done? —Preceding unsigned comment added by 70.229.42.54 (talk) 16:31, 30 April 2010 (UTC)

Forget your IR machine for a minute. Above it says: I was wondering if anyone knew of a way to tell the difference between nylon 6 and nylon 6,6?and on page two of this [6] the text reads For this market, the PHAZIR is programmed with a chemometric analysis program that not only identifies major fiber groups (wool, nylon, polyester, cotton), but can distinguish accurately between Nylon 6 and Nylon 6-6. Are you saying you have the same model with the same caperbilities or just some other IR machine? --Aspro (talk) 18:17, 30 April 2010 (UTC)

animal government

I know we talk about "queen ants" but do any animals actually have any government? 82.113.106.110 (talk) 14:32, 29 April 2010 (UTC)

Depends on definitions. Wikipedia defines "Government" as:

"A government is the organization, machinery, or agency through which a political unit exercises its authority, controls and administers public policy, and directs and controls the actions of its members or subjects"

Animals are known to exert some kind of "authority" (again, this needs to be defined) over other animals. But as for controling/administering policy, nope. I think you need to tell us what definition you're using. 196.38.62.178 (talk) 14:40, 29 April 2010 (UTC)

(ec) It depends how you define "government." Certain animals do cooperate and have extremely intricate social hierarchies (meerkats, mole rats, wolf packs) that we sometimes call "clans" or "colonies" or things of that nature. They look not dissimilar from certain "primitive" forms of human government. Ants are eusocial, and are maybe best understood as superorganisms, which may or may not be similarly to your definition of "government." --Mr.98 (talk) 14:43, 29 April 2010 (UTC)

Rooks and owls have parliaments [7].--Shantavira|^{feed me} 15:01, 29 April 2010 (UTC)

Do you mean do any animals have leaderships made up of more than one individual? Some species have groups with an alpha pair - a breeding pair that are in charge, rather than just an alpha male (or alpha female) in charge. There are also species where the group will have a detailed order of precedence, but I don't think any individuals other than the one (or two) at the top play a significant leadership role. --Tango (talk) 15:09, 29 April 2010 (UTC)

If we take government to be equivalent to 'social hierarchy', then plainly yes. You could probably even discern 'taxation systems' and 'public infrastructure projects' if you looked closely. Vranak (talk) 15:51, 29 April 2010 (UTC)

BTW, queen ants are only egg-laying machines; they don't govern. --Chemicalinterest (talk) 19:40, 29 April 2010 (UTC)

See http://multilingualbible.com/proverbs/30-27.htm. -- Wavelength (talk) 23:12, 29 April 2010 (UTC)

Not sure what you're trying to do here. The biblical proverb is "The locusts have no king yet they go forth in bands" and it looks like it means that a group of people don't need a leader to be united (or something like that). This really doesn't help our questioner. 196.38.62.178 (talk) 14:30, 30 April 2010 (UTC)

Most animals appear to be in favor of anarchy, though it is common to refer to those making up the lower levels of membership in the major US parties as sheep. Googlemeister (talk) 20:32, 30 April 2010 (UTC)

I realize that that is a counterexample to what the original poster mentioned, but that proverb might suggest that they are ruled by instinct. I did not intend it to be interpreted as a model for humans to imitate, as in the case of ants

(http://multilingualbible.com/proverbs/6-6.htm; http://multilingualbible.com/proverbs/6-7.htm; http://multilingualbible.com/proverbs/6-8.htm; http://multilingualbible.com/proverbs/6-9.htm; http://multilingualbible.com/proverbs/6-10.htm; http://multilingualbible.com/proverbs/6-11.htm). -- Wavelength (talk) 21:12, 1 May 2010 (UTC)

[For clarity, I am revising "I realize that this is" to "I realize that that is". -- Wavelength (talk) 22:43, 1 May 2010 (UTC)]

See Dominance hierarchy. -- Wavelength (talk) 00:18, 1 May 2010 (UTC)

Biological Classification

I was thinking about biological classification and I came across this picture. How does man fit into it? Could someone please list my labels in this list. For example, my species is human, my genus (I think) is primate, etc... THANKS! •• Fly by Night (talk) 15:03, 29 April 2010 (UTC)

See species:Homo_sapiens_sapiens. CS Miller (talk) 15:12, 29 April 2010 (UTC)

...and note that primate is an order, not a genus. Gandalf61 (talk) 15:16, 29 April 2010 (UTC)

A somewhat less daunting list, with all the relevant entries from kingdom on down, is in the taxobox at the top of Human. Deor (talk) 19:07, 29 April 2010 (UTC)

Fact checking from Fight Club

I found some parts from the novel Fight Club extremely suspicious (for not saying, outright false). I pasted them below. Is there any truth in them? Mr.K. (talk) 15:18, 29 April 2010 (UTC)

1. "they used their urine and the urine of their dogs to wash their clothes and hair because of the uric acid and ammonia."
2. "Spiders," (...) "could lay their eggs and larva could tunnel, under your skin."
3. "It doesn't matter," Tyler says. "If the applicant is young, we tell him he's too young. If he's fat, he's too fat. If he's old, he's too old. Thin, he's too thin. White, he's too white. Black, he's too black." This is how Buddhist temples have tested applicants going back for bahzillion years, Tyler says.
4. "The three ways to make napalm: "One, you can mix equal parts of gasoline and frozen orange juice concentrate," the space monkey in the basement reads. "Two, you can mix equal parts of gasoline and diet cola. Three, you can dissolve crumbled cat litter in gasoline until the mixture is thick."
5. "A cathode ray tube can hold 300 volts of passive electrical storage, so use a hefty screwdriver across the main power supply capacitor, first. If you're dead at this point, you didn't use an insulated screwdriver."
6. "A sort of fun explosive is potassium permanganate mixed with powdered sugar. The idea is to mix one ingredient that will burn very fast with a second ingredient that will supply enough oxygen for that burning. This burns so fast, it's an explosion. Barium peroxide and zinc dust. Ammonium nitrate and powdered aluminum. Barium nitrate in a sauce of sulfur and garnished with charcoal. That's your basic gunpowder."
7. "You take a 98-percent concentration of fuming nitric acid and add the acid to three times that amount of sulfuric acid. You have nitroglycerin. Mix the vitro with sawdust, and you have a nice plastic explosive. A lot of the space monkeys mix their vitro with cotton and add Epsom salts as a sulfate. This works, too. Some monkeys, they use paraffin mixed with vitro. Paraffin has never, ever worked for me."

1. You don't think Wikipedia would over look that particular use of urine do you.--Aspro (talk) 15:36, 29 April 2010 (UTC)
2. No larva, no burrowing under the skin. The Burk Museum of Natural History and Culture has a myth busting site: [8]--Aspro (talk) 20:11, 29 April 2010 (UTC)
3. *
4. It would be a bit irresponsible for the publisher to allow the author to be too precise about these things -don't you think?--Aspro (talk) 15:48, 29 April 2010 (UTC)
5. Yes, the output capacitor and tube can hold a charge. See Wikipedia:Reference_desk/Archives/Science/2010_April_12#Old_television_smoky_exploding_madness.21. --Aspro (talk) 15:55, 29 April 2010 (UTC)
6. Potassium permanganate reacts with glycerin; it probably does with sugar, belching clouds of water vapor, carbon dioxide gas, spattering black manganese dioxide smoke; messy, messy, messy... Zinc dust will react with barium peroxide to produce barium oxide and zinc oxide smoke. It might not make a good explosive since there are no gaseous products. Ammonium nitrate and aluminum would make aluminum oxide, nitrogen gas, and probably water vapor. Potassium nitrate is normally used instead of barium nitrate in gunpowder. Caution: Barium fumes and compounds are toxic.--Chemicalinterest (talk) 19:48, 29 April 2010 (UTC)
7. Where is the glycerin? Nitric acid reacts with glycerin according to the nitroglycerin article using sulfuric acid as a catalyst to produce nitroglycerin. Extremely dangerous, may detonate when created. --Chemicalinterest (talk) 19:48, 29 April 2010 (UTC)

Wikipedia contains details on nitroglycerin and napalm and gunpowder among other dangerous things. I'm not sure it makes any sense to assume that just because the work is fiction, the author couldn't—or wouldn't—have looked into these things and published them accurately. There is no law against it. --Mr.98 (talk) 16:07, 29 April 2010 (UTC)

According to an interview with Palahniuk, his explosive recipes in the book are correct, but the ones in the movie are not. --Mr.98 (talk) 16:04, 29 April 2010 (UTC)

I've uncollapsed and numbered the questions, so they're easier to respond to. Buddy431 (talk) 19:39, 29 April 2010 (UTC)

6. I think permanganate (a strong oxidizer) and powdered sugar would likely deflagrate quickly in an explosion like manner. He's essentially right in his assertion: pretty much any pyrotechnic is a fuel (sugar, charcoal, metals like zinc or aluminum will work) along with a strong oxidizer (permanganates, nitrates, peroxides all fit the bill). And he's right about gunpowder: a nitrate, charcoal, and a bit of sulfur. Usually potassium nitrate is used because it's more widely availiable than Barium nitrate, but it's only the nitrate that's important.

7. I think you're missing an ingredient in nitroglycerine: you need a source of glycerol! But yes, nitroglycerine is made by adding glycerol to a solution of concentrated nitric and sulfuric acids. This mix generates Nitronium ions, a strong electrophile that attacks the oxygens on glycerol. As in the previous question, the nitrates are acting as an oxidizing agent. I suspect that all of the mixes listed would at least burn, though maybe not explode like you want them to (sawdust, cotton, and paraffin can all act as a fuel). However, 98% nitric acid is quite expensive. It's much cheaper to buy nitrates and make some of the gun-powder like substances that are mentioned in your question number six.Buddy431 (talk) 19:58, 29 April 2010 (UTC)

And please don't try making any of this. Apart from the obvious explosion/fire risk, concentrated nitric acid and sulfuric acid are uber nasty. Buddy431 (talk) 19:57, 29 April 2010 (UTC)

Plus, playing around with these kinds of things could easily land you in jail with no parole (either for attempted murder/terrorism with weapons of mass destruction for an extra 20-years-to-life tacked on, or at the very least for criminal endangerment of others). Definitely not a good idea. 76.103.104.108 (talk) 07:11, 30 April 2010 (UTC)

2. While not a spider, the Botfly will lay eggs under the skin of the host. Icky. Buddy431 (talk) 20:01, 29 April 2010 (UTC)

Fuming nitric acid is probably restricted because of the ease by which explosives may be made from it. --Chemicalinterest (talk) 20:07, 29 April 2010 (UTC)

1) Urine was used in Ancient Rome to wash clothes (at least by those Romans who couldn't afford soap -- which was at the time damnably expensive).

4) Of these three recipes, only the one with the cat litter would produce a useful grade of napalm. A better recipe, though, would be to dissolve rubber or Styrofoam instead of cat litter.

5) Capacitors can indeed store enough charge to zap you very badly (in extreme cases, they could even deliver a lethal shock). Don't screw around with high-voltage components unless you really know what you're doing.

6) KMnO₄ + C₆H₁₂O₆ → MnO₂ + CO₂ + H₂O (gunpowder-like deflagration). BaO₂ + Zn → BaO + ZnO (will burn with green flame and white smoke, but will not explode). NH₄NO₃ + Al → NH₃ + Al(NO₃)₃ (will also deflagrate, but with less explosive force than plain ammonium nitrate, and will release toxic ammonia gas). Ba(NO₃)₂ + S + C → BaO (highly toxic) + N₂ + SO₂ + CO₂ (explosively deflagrates just like gunpowder). Actual gunpowder uses KNO₃ or NaNO₃ because they're more readily available and contain more oxygen (as nitrate) per unit weight. Don't try any of this at home if you don't want to risk your own life and those of your family.

7) A mixture of fuming nitric and sulfuric acid will react with glycerin to make nitroglycerin; mixing this with sawdust will produce a form of dynamite. Nitroglycerin is EXTREMELY unstable and liable to blow up in your face upon the slightest shock, like if you sneeze on it; and when it does blow up, it can explode with enough force to turn a good-sized apartment building to a pile of rubble (with you at the bottom of the pile). In summary: DON'T TRY ANY OF THIS AT HOME!!! 76.103.104.108 (talk) 07:47, 30 April 2010 (UTC)

Notes to 76.103.104.108: When KMnO4 oxidizes sugar, it produces potassium hydroxide, a strong base. When NH4NO3 reacts with aluminum, nitrogen is produced. You can never get your equation balanced because the aluminum is being oxidized and the nitrate isn't being reduced. The reaction is: 3 NH₄NO₃ + 2 Al → Al₂O₃ + 6 H₂O + 3 N₂ SO₂ isn't normally produced in gunpowder exhaust. It would be a form of BaS. --Chemicalinterest (talk) 16:24, 30 April 2010 (UTC)

I stand corrected on the gunpowder question. 76.103.104.108 (talk) 02:14, 1 May 2010 (UTC)

Superconductivity and gravity

What are the latest news regarding superconductivity and gravity? Are there any hopes to levitate objects as done with magnetic field? If so, then how is the object's response to this force cancellation; is it just apparent on the surface or in every point?--Email4mobile (talk) 18:15, 29 April 2010 (UTC)

Lots of things are levitated via magnetic field. And you don't even need a superconductor to do it. See Maglev train. --Jayron32 18:43, 29 April 2010 (UTC)

Some maglevs are using superconductors now, though. There now exist "High Temperature" superconductors that operate at the balmy temperature of -196 C. This may seem very cold (and it is), but that's the temperature of liquid nitrogen, a relatively cheap and easily handled coolant. Buddy431 (talk) 19:30, 29 April 2010 (UTC)

I meant something like this.--Email4mobile (talk) 02:12, 30 April 2010 (UTC)

I don't have the physics background to evaluate any of those claims, but a lot of it looks pretty fishy. Wikipedia has articles on a number of the characters mentioned: Ning Li (physicist), Martin Tajmar, Eugene Podkletnov. They seem a bit shady. Our Antigravity article covers some of the claims by these characters, i.e. here, and indicates that as of yet, none of their claims have been verified by any independent experiments. Buddy431 (talk) 05:53, 30 April 2010 (UTC)

The PDF rang loud bells for me too as it mentions Eugene Podkletnov more than once. Don't bother trying to get your head around anything he says, nor to even finish reading anything that mentions his name. It's all nonsense, based on some odd measurements in physics . Cold fusion is a piece of cake in comparison and far more likely to succeed.--Aspro (talk) 15:12, 30 April 2010 (UTC)

Edge of the Universe

I understand current models of the universe establish there is no boundary in three dimensions as we may live within a 4-sphere. If that's the case though then if you consider the universe in 5 dimensions there will still be an edge. So what's over THAT edge? TheFutureAwaits (talk) 18:34, 29 April 2010 (UTC)

Think about a 2-sphere in 3-space. There's no edge. If you lived in 2-dimension land on that sphere, every point in your world would look the same to you. Rckrone (talk) 18:45, 29 April 2010 (UTC)

See shape of the universe for more details on this issue. --Jayron32 18:50, 29 April 2010 (UTC)

While it can help to think about the universe embedded in higher-dimensional space, it is inadvisable to do so. It's just a way of getting your head around it, it doesn't actually represent anything in reality. (There is the theory of Brane cosmology that includes something similar, but that's not important.) Most likely, there is no edge to the universe in anything meaningful sense. --Tango (talk) 18:51, 29 April 2010 (UTC)

I agree. This is the way I often see it: the laws of physics exist within the universe only. There is no existence without these laws. Therefore there can be no boundary with something that has no existence, because it does not even have dimensions which would be needed in order to say where it is. There is just the universe.--Aspro (talk) 19:09, 29 April 2010 (UTC)

If there is no edge then what if we just continue to go then where are we going to?75.168.119.109 (talk) 22:36, 29 April 2010 (UTC)

There are two possibilities. Either the universe is infinite in extent and you just keep on going for ever and nothing interesting happens or the universe is closed and if you keep going far enough you end up going around in a big circle and end up back where you started. --Tango (talk) 22:48, 29 April 2010 (UTC)

This is no sense how could we go that far then end up going around and back where we started. I think there must be a boundary but you could not go anymore when you get to the boundary or it, the boundary, destroys everything touch it.75.168.119.109 (talk) 22:58, 29 April 2010 (UTC)

That is simply not true. A universe in which you can go all the way round and get back to where you started is possible within mainstream cosmological theories. It is like the surface of the Earth - if you go far enough, you'll get back to where you started. There is no "end of the world" where you fall off into oblivion. The (spacial part of the) universe could be a 3-sphere, so very much like the surface of the Earth, just a dimension higher, or it could be a 3-torus (the 3D equivalent of the surface of a ring doughnut), which still allows you to go all the way around the universe, but the universe would be flat (which fits with observations). (There are more complicated shapes, but 3-spheres and 3-tori are the simple ones worth considering in this discussion.) --Tango (talk) 23:25, 29 April 2010 (UTC)

How could you compare the universe same as Earth? Earth shape is a circle and that's how you could go around it but not the universe. I still think that's nonsense to go around the universe.75.168.119.109 (talk) 23:43, 29 April 2010 (UTC)

Well, you are wrong. That's all there is to say about it (Jayron gave a link to our article which has references to back up my statement). --Tango (talk) 23:44, 29 April 2010 (UTC)

There are two ways that the universe works. One is that it is finite, but with no edges. Sounds crazy, but it does work. Imagine that you are an 2-D ant living on (technically within, but w/e) the surface of a sphere. You can go anywhere you want as far as you want, but you end up where you started eventually. It is a finite surface, but no edge. The sphere is a 2-D surface, just curved. Now scale that up to three dimensions. You get a curved, finite, 3-D space, but with no edges. The other option is that the universe is infinite, but that is a much easier concept to grasp. KyuubiSeal (talk) 02:28, 30 April 2010 (UTC)

Healing of cut

How long (typically) after a minor cut (such as a paper cut) does the skin become impermeable to viruses? Thanks. —Preceding unsigned comment added by 160.109.98.44 (talk) 19:40, 29 April 2010 (UTC)

After a good scab (don't pick it) is developed. If no viruses have gotten in, you should be safe. --Chemicalinterest (talk) 19:49, 29 April 2010 (UTC)

But even if viruses do get in does not mean the end of the world. The human body has a great immune system for dealing with the average virus. It works best though if you let a few viruses in now and again so that it can form and/or maintain immunity against them. Richard Avery (talk) 06:24, 30 April 2010 (UTC)

Unless that virus is Human Immunodeficiency Virus, in which case you can kiss your immune system goodbye. If you're working in a situation where dangerous viruses are likely to be transferred, you should take safety precautions dictated by an authority on the matter, and not take advice from random people on the internet, regardless of whether you have a paper cut or not. Buddy431 (talk) 15:36, 30 April 2010 (UTC)

Dissolution of Metals

Would dissolving of metals necessarily mean the metal was oxidized? For example, Ta dissolves in KOH. Is is being oxidized. --Chemicalinterest (talk) 20:29, 29 April 2010 (UTC)

Yes. Metals do not dissolve as neutral atoms or molecules the way that most nonmetals do (for example, gasseous O₂ dissolves in oxygen as O₂ molecules, neutrally charged). Instead, metals only dissolve if they are oxidized. So when, say, Magnesium metal dissolves in an acidic solution, the magnesium is oxidized from the metal to the Mg²⁺ ion. In such cases, there has to be a corresponding reduction reaction. In the case of magnsium dissolve it will be the formation of H₂ gas from H₃O¹⁺ ions in the acid solution. --Jayron32 20:40, 29 April 2010 (UTC)

If you dissolve the metal in mercury it does not oxidise in that process. The same would be try of metal dissolving in other molten metals. There could be some other solvents that take up metals as complexed neutral atoms. may be liquid ammonia. Graeme Bartlett (talk) 22:44, 29 April 2010 (UTC)

Potassium is sometimes dissolved in liquid ammonia and used as a strong reducing agent. However, people think that the extra electron is removed from the potassium and solvated in the ammonia, so really it's still the potassium ion that's dissolved. Buddy431 (talk) 23:34, 29 April 2010 (UTC)

Here's the appropriate articles: Ammonia#Solutions_of_metals as well as solvated electron. Mr. Bartlett mentioned mercury solutions: those are generally known as Amalgams. Buddy431 (talk) 23:38, 29 April 2010 (UTC)

You can certainly have zero-valent metals (i.e., not "ions") in solution...Tetrakis(triphenylphosphine)palladium(0) is just one example of many hundreds of soluble organometallic compounds. It's just "just atoms" (those ligands are bound to it), but "solvent having specific affinity to solute particles" is how most dissolving works. So all you need is an organic liquid that can serve as a Lewis-base ligand for a metal atom, and you have the same idea as water serving as a Lewis-base coordinating to a cation. One thing I don't know is if you can literally "dissolve the metal". All the organometallics I know are formed by reducing the dissolved metal cation back to zero. DMacks (talk) 01:03, 30 April 2010 (UTC)

I quite accept that it is possible to have a zero-oxidation-state metal, properly coordinated with the right ligands, which is then soluble. The question is can you take a chunk of metal and put it into something, and have it dissolve without any oxidation occuring. I am sure there are some exotic cases (nothing is impossible, per se), but under normal circumstances, for any normal definition of "metal" and "dissolve" then probably not. --Jayron32 02:54, 30 April 2010 (UTC)

Gold in mercury does this. Graeme Bartlett (talk) 09:09, 30 April 2010 (UTC)

See Amalgam (chemistry) Googlemeister (talk) 20:30, 30 April 2010 (UTC)

Death

After we died then where are we going to? Is reborn one of the possible way?75.168.119.109 (talk) 22:38, 29 April 2010 (UTC)

This is a topic explored by all religions, philosophies, and sciences as long as human has existed. See our articles on Death and Afterlife. Specifically, see reincarnation for the topic on "rebirth". --Kvasir (talk) 22:45, 29 April 2010 (UTC)

Since you have asked on the science desk, I'll give a scientific answer: Once you die, that is it. Your conciousness ceases to exist and your body decays. Pretty much every religions involves some kind of life-after-death, but they are very different in different religions. --Tango (talk) 22:50, 29 April 2010 (UTC)

You mean once we die then that's it. That's mean once we die then we are same as if we are not exist. It is hard to imagine how could that be like.75.168.119.109 (talk) 22:53, 29 April 2010 (UTC)

Your consciousness relies on the electrical signals among the cells in your brain. When you die, those signals stop and your consciousness ceases to exist, as Tango said. 196.38.62.178 (talk) 09:45, 30 April 2010 (UTC)

See http://multilingualbible.com/ecclesiastes/9-5.htm; http://multilingualbible.com/ecclesiastes/9-10.htm.

-- Wavelength (talk) 23:08, 29 April 2010 (UTC)

Remember what it was like to be you before you were born? No? Well, that's what it's like when you are dead.--Eriastrum (talk) 23:11, 29 April 2010 (UTC)

If you are going to give a religious answer on the science desk, please at least give a summary of the various different religious viewpoints. --Tango (talk) 23:16, 29 April 2010 (UTC)

I suggest that the question probably should have been moved to the Humanities desk from the get-go. Kingsfold (talk) 11:47, 30 April 2010 (UTC)

Is what really happen to us after we die?75.168.119.109 (talk) 23:18, 29 April 2010 (UTC)

What is scientific about just saying that the soul goes nowhere when one dies? It is just what people who don't believe in God believe. I believe (an unpopular belief) that people who are saved (believe that you are a sinner, that God can pay for your sins, that you cannot pay for your sins, to trust in God for redemption) go to heaven, and people who are not saved go to hell. Simple. --Chemicalinterest (talk) 23:20, 29 April 2010 (UTC)

You are misrepresenting the scientific view - science doesn't involve a concept of souls at all. It is scientific because it is the simplest answer that is consistent with observations - that is how science works. --Tango (talk) 23:29, 29 April 2010 (UTC)

You are true when you said that science does not involve a concept of souls. It, like origins, is relegated to the realm of philosophy. --Chemicalinterest (talk) 00:38, 30 April 2010 (UTC)

Before you were born you did not exist. But even though your body goes away, your soul never dies. --Chemicalinterest (talk) 23:27, 29 April 2010 (UTC)

That's not necessarily a scientific view or a religious one. References such as Job 38:7, Eccl 12:7, and Jeremiah 1:5 indicate that there was an antemortal existence, or (if you read those scriptures differently) at least that one is possible. Kingsfold (talk) 11:27, 30 April 2010 (UTC)

I disagree. Science has found the answer. People just won't accept it. 67.243.7.245 (talk) 11:49, 2 May 2010 (UTC)

I could see nobody actually knows the answer for this. But I hope after we die we would not be like never exist, is better to be reborn and become a human again.75.168.119.109 (talk) 23:25, 29 April 2010 (UTC)

If your soul has lived through 100,000 generations of life which was a period miserable brutish suffering, loneliness and torture, and all that is waiting is 1,000,000,000 more generations just as miserable, with no prospect of one bit of improvement, then an end might be preferable to more reincarnations. Going to some Heaven and living happily foreverafter would be a better prospect, as would being reincarnated into some happier state leading to greater enlightenment. Edison (talk) 20:46, 30 April 2010 (UTC)

Unfortunately, the universe tends not to work in the way that makes us happiest. --Tango (talk) 23:29, 29 April 2010 (UTC)

Well if you hope that, that's fine. This is a question to which there is no scientific answer beyond either "it cannot be known" or "your body decays", depending on whether you consider 'you' to be your consciousness or your physical body. If you had asked on the humanities desk, you would have got versions of Kvansir's excellent answer (the first answer you got here). Being reborn is certainly an option proposed by several religions, and you are free to hope for that. If you find that's what you really believe will happen, that's fine too. But nobody here can tell you which afterlife to believe in. 86.178.225.111 (talk) 23:53, 29 April 2010 (UTC)

I disagree. There is a scientific answer: your conciousness ceases to be. It can't be proven any more than anything else in can in science, but it is still be most reasonable theory. --Tango (talk) 23:58, 29 April 2010 (UTC)

If you are saved, even better. By the way, what is atheism? Just another religion that denies there is a God. --Chemicalinterest (talk) 23:28, 29 April 2010 (UTC)

Strong atheism can be described as another religion, but weak atheism (which is what the vast majority of atheists are - I don't think I've ever knowingly met, online or in real life, a strong atheist) can't. A key (and I would say, defining) feature of religion is that it claims to know absolute truth. Weak atheism doesn't do that. --Tango (talk) 23:32, 29 April 2010 (UTC)

Strong atheism makes sense when people care to define the term god. 67.243.7.245 (talk) 11:51, 2 May 2010 (UTC)

Some might claim to know absolute truth by arguing for evolution in cases where creation clearly has the upper hand. --Chemicalinterest (talk) 00:36, 30 April 2010 (UTC)

First, "arguing for" != "absolute truths", and secondly, you are speaking about the vacuous case here... --Stephan Schulz (talk) 08:17, 30 April 2010 (UTC)

It is folly to presume anything about the unknowable, e.g. post-death realities. Vranak (talk) 00:02, 30 April 2010 (UTC)

Physical body stops working and decays. Spirit/soul/conciousness, nobody knows. People have been working on it for millennia, and we still haven't found an answer yet. KyuubiSeal (talk) 00:32, 30 April 2010 (UTC)

I believe that scientists in the past have actually conducted experiments to look for human souls leaving the body upon death (it's been mentioned here before). Some positive results were indeed reported (see Duncan MacDougall (doctor), for example) but nothing that could be unambiguously reproduced/confirmed beyond reasonable doubt by others. --Kurt Shaped Box (talk) 07:07, 30 April 2010 (UTC)

Yet more evidence that people of faith are desperate for evidence. 67.243.7.245 (talk) 13:35, 1 May 2010 (UTC)

Its a one-way street. Once you die, you cannot know with human knowledge what is after death. --Chemicalinterest (talk) 00:36, 30 April 2010 (UTC)

I don't believe it's unknowable. A spirit, the afterlife or reincarnation relies on mind /body or Consciousness /Matter dualism. We have been investigating it for millennia and so far there is so far no good evidence to suggest the mind is separate from the brain, but good evidence just keeps piling up that the mind and brain are not separate. I think it can and will be conclusively proved that the mind is a result of the brain, maybe it will take 50 or 100 years until we download someone's mind into a computer brain or something, but it will happen eventually. We're not that far off achieving the raw power, but there'll obviously be a lot more to it then just that.. However, even then I don't believe religion will disappear, they will justify it away just like they have every time science has proved them many times wrong in the past. 203.110.235.1 (talk) 00:45, 30 April 2010 (UTC)

Basically, we have no clue. This isn't a religious debate, and I'm not sure how we got there. Nothing to do with evolution, atheism, God, or religion. We have no evidence for the soul existing in this world after death. Maybe we go to heaven, maybe our soul goes nowhere, we really don't know. On a more humorous note: http://xkcd.com/659/ KyuubiSeal (talk) 01:36, 30 April 2010 (UTC)

Here on the Science desk, you're going to get the science answer, and science demands evidence. Since there hasn't been any evidence there is an afterlife, the presumption is that there isn't one. Comet Tuttle (talk) 03:48, 30 April 2010 (UTC)

Absence of evidence is not evidence of absence. Since there is no evidence for or against, science can have no opinion. There is nothing wrong with having undecidables in a discipline. Ariel. (talk) 05:55, 30 April 2010 (UTC)

Science usually uses Occam's razor as a tiebreaker in these situations, which comes down on the side of no afterlife. As far as science is concerned, there is no problem to solve here. There is no reason to question what happens after death - the answer is obvious. It is just that humans don't like that answer, so choose to believe a different one despite the lack of evidence. --Tango (talk) 06:26, 30 April 2010 (UTC)

I would dispute that there's been no evidence. We're lacking proof, not evidence. Kingsfold (talk) 11:39, 30 April 2010 (UTC)

I would be very interested in seeing any evidence you have for an afterlife. --Tango (talk) 17:28, 30 April 2010 (UTC)

For something that is sometimes interpreted as evidence, see Near Death Experience. It's not a question that they regularly occur, but the explanation for these experiences is hotly debated. Some people will tell you that it's just a scientifically explained brain phenomenon on the verge of death, and others will claim to have evidence to support the claim that it proves that conciousness is not tied with the brain as previously thought. Either way, it is extremely fascinating (at least to me). Falconus^{p t c} 04:30, 30 April 2010 (UTC)

I too find it interesting. By the way, (not really science, per se - but seems like an appropriate thread as any in which to ask) what is the name for the theory that sapience is the result of the presence of a soul? I read someone's take on this a while back and found it good 'food for thought'. --Kurt Shaped Box (talk) 07:13, 30 April 2010 (UTC)

It doesn't solve your problem, but only adds one more thing to what you're trying to answer. Like the creation problem, you're not only not answering how exactly this came to be, but you're adding one more thing to the problem you have trouble explaining. 67.243.7.245 (talk) 13:35, 1 May 2010 (UTC)

Many scientists think they know the answer. Many laypeople don't want to hear it. 67.243.7.245 (talk) 13:49, 30 April 2010 (UTC)

We cannot take serious any reasoning based on concepts and assumptions that are not well defined/supported. Not only can't we invoke some undefined afterlife, Heaven, Soul, etc. etc. but we shouldn't make other hidden assumptions e.g. about the nature of time, about whether or not information is exactly conserved by the laws of physics. Any assumptions should be made explicit.

So, if I assume that time does not really exist, in the sense that there is no physical pointer that points out the present moment relative to the past and the future, which makes that only the present moment really exists, then you don't really die. All the past states in which you "were" alive simply exist. One has to note that this idea of time is far better motivated than the naive interpretation in which only the present moment really exists. In fact, the naive notion of time violates special relativity, see e.g. the Andromeda paradox article for a clear illustration of why the physical status of yesterday should be the same as the status of today.

Another assumption one could make is that information is exactly conserved in the universe. Both in classical physics and in quantum physics information does not get lost. However, in the Copenhagen interpretation of quantum mechanics, this is only true in a probabilistic sense, while in the Many Worlds interpretation this is true in a more exact sense. So, this assumption is quite well motivated.

So, even if time were to somehow exist in the naive interpretation, the past would still exist in the present moment, albeit in a scrambled form. Yesterday then exists inside today in a sphere of one light day diameter. But to see it, you would have to apply the exact time evolution operator to it. If you belive in the strong artificial intelligence assumption, the way you are are implemented does not affect your consciousness. So, the fact that the copy of you in yesterday's state is scrambled within that one light day sphere, should not be relevant to his consciousness. Of course, his entire physical world is scrambled with him in it, so he subjectively experiences being alive in yesterday world. But the point is that it all exists within today's world. Count Iblis (talk) 15:03, 30 April 2010 (UTC)

(ec) Just like the ghost question asked by the same OP, the answer to this one is pretty much that there is an overwhelming scientific consensus that counter-indicates the presence of rebirth, afterlife, and so on. If the religious folks want to weasel up some contorted definition about the afterlife, and play like it's not subject to scientific reason, then ... by the same logic, those religious people are all pink aardvarks who are not subject to rational, scientific reason. The instant you make a claim about some kind of tangible, extant soul - or afterlife - we can start questioning the logical consequences that would follow from such a claim. If there is a heaven, then where is it? If there is a soul, what is it made of? If the answers to these are "nowhere" and "nothing", then we have a resounding victory for the "sorry, OP, there is no afterlife" camp. If the religious folks want to start digging their hole deeper, they can make shit up to explain the soul and the afterlife. Every single detail they explain will be subject to the same demands for observational evidence as any other scientific claim. If the soul is made of some luminiferous ether, we have already shown that to be inconsistent with our observations of the universe. If heaven is located above the clouds, I have some bad news for you, because we've been there, and it's pretty drab and empty (though it sure does excite the plasma physicists). As the technologies and thought processes available to humans expand, we become better able to explain all of the things we are experiencing without the need for vague and hand-wavey answers. And as for User:Chemicalinterest - while I respect your right to hold your beliefs, I have no qualms telling you that your beliefs are simply moronic, and do not stand up to even the slightest scientific inquiry. The Resurrection of Christ could be explained by an ascent to heaven - or the body might have been eaten by coyotes or jackals. Which is the scientific explanation? If you want to stick to your guns and tell me about heavenly ascent, I have some very simple questions about how a body can levitate, pass through solid rock, and then fly to a place above the clouds, and so on. Do you really feel that there is a scientific ANY explanation for those details, or do you want us to just resign to the idea that "a pink aardvark did it for the lulz"? Nimur (talk) 15:18, 30 April 2010 (UTC)

Coyotes, to my knowledge, did not even live in Palestine during Roman times, so they must be ruled out as a scientific explanation for the disappearance of the body. We should not introduce explanations that are inconsistent with known historical fact. Nimur (talk) 15:20, 30 April 2010 (UTC)

Would I call your immense faith that there is no greater purpose, and that life ends after death "moronic"? Absolutely not, that would be very closed-minded of me. Truth is that neither of us have a clue, scientifically speaking, as both of us have the distinction of being alive, and have to date found no way to test hypotheses dealing with the afterlife (well, that is, test them and then record the results). Falconus^{p t c} 19:01, 30 April 2010 (UTC)

The concept of an afterlife is based on faith, not proof. If you could prove it, there wouldn't be any debate about it. Science demands scientific evidence, and there isn't any. That doesn't mean there's no afterlife, it simply means science has not figured out a way to detect and/or measure it. So anything science says about it is also based on "faith". ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:33, 30 April 2010 (UTC)

The concept of an afterlife is not needed to explain any observed phenomena - so there is no need to test for it. It's also not falsifiable - so we couldn't if we wanted to. The only reason anyone would want to test for it would be to shut everyone up. All the evidence as well as common sense says that when we die our brains shut off permanently and our consciousness ends - I don't know why anyone would want more than that. Zain Ebrahim (talk) 17:02, 30 April 2010 (UTC)

It's the faith, or hope, that there's something more than just this. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:44, 30 April 2010 (UTC)

Reduction of Iodate

What is the half equation for the reduction of iodate $({IO_{3}}^{-})$?--115.178.29.142 (talk) 23:06, 29 April 2010 (UTC) Reduction to what? I₂? I^-? HIO?

Reduction to HIO is: IO3− + 5 H+ + 4 e− ⇄ HIO(aq) + 2 H2O (+1.13V)

Reduction to I2: 2 IO3− + 12 H+ + 10 e− ⇄ I2(s) + 6 H2O (+1.20V) --Chemicalinterest (talk) 23:24, 29 April 2010 (UTC)

(edit conflict) Reduction to what? At Standard electrode potential (data page) we have two reactions where iodate is reduced, one to HIO and one to I₂ (+1.13 V and +1.20 V, respectively). The half reactions are given on that page (I see I've been beaten... must still post) Buddy431 (talk) 23:29, 29 April 2010 (UTC)

I had it on my computer, so I had easier access. --Chemicalinterest (talk) 00:24, 30 April 2010 (UTC)

Why do birches grow in clumps

I've often seen 2-5 birch trees growing out of one compact spot like in the image at right. Other trees like oaks and pine trees I usually see growing individually. Is there a term for this clumping? Does it stem (pun intended) from birches being considered shrubs, like the Birch article states in the first section? Why does this not happen with other trees? Or is this all observation bias on my part? Dismas|^(talk) 23:50, 29 April 2010 (UTC)

Well, it can be the result of coppicing (there may be a single very short trunk that all the other trunks come out of, but it can be cut so low that it ends up getting covered with soil). It could also be a natural occurrence similar to coppicing - a tree may have died back to a stump and then had many shoots regrow. Our article does mention birch as one of the trees that can be coppiced. If it is intentional coppicing, then you'll probably see lots of clumps like that nearby. --Tango (talk) 00:04, 30 April 2010 (UTC)

I've used this memory crutch for decades, to help tell the difference between Aspens and Birches:

Aspens alone, Birches in bunches.

Ergo, it has to be more than just an accident. DaHorsesMouth (talk) 00:32, 30 April 2010 (UTC)

A good way to tell the difference between aspens and birches is by their bark -- birch bark is white and has a papery texture to it (the ancient Russians even used it as a paper substitute), while aspen bark is brown and glossy. 76.103.104.108 (talk) 02:21, 1 May 2010 (UTC)

Well, since aspens can form into clonal colonies some consider the largest organisms on earth, you're either very right (the aspen is alone because it's the whole freaking forest) or you're very, very wrong. Matt Deres (talk) 00:50, 30 April 2010 (UTC)

Just from personal observation, birches will seed even in deep shade so their seedlings will become a forest. It is possible that aspens need more daylight for their seeds to sprout, which means they will only be single specimens. --TammyMoet (talk) 15:00, 30 April 2010 (UTC)