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Coldest Place in the Universe
Chris Gondek writes "The Sydney Morning Herald has an article on how NASA has released a high-quality image of the coldest place found in the universe. Five thousand light years from Earth in the constellation of Centaurus, the nebula, a gas cloud formed from a dying star, has a temperature of minus 272 degrees.
It is only one degree warmer than absolute zero, the coldest possible temperature, when atoms cease to vibrate and radiate no heat whatsoever.
This radiation is the remnant of the Big Bang, the explosion which forged the universe in trillion-degree temperatures. More than 11 billion years later, this heat has cooled to minus 270 degrees, but is still detectable."
temperature is defined by the movement of atoms, right? how can microwave radiation have temperature?
if i got my physics right, radiation just induces movement of atoms... ?-)
the computer is online
i am not at it
what a waste of ressources
But doesn't that assume heat is continuous and not quantised?
Funny, I've always thought going from -272 degrees to -270 degress is called heating.
That was referring to the background radiation of the Universe, which has cooled over time since the Big Bang. The astonishing thing is that the nebula is colder still.
Real Daleks don't climb stairs - they level the building.
What I want to know is how they know the boomerang nebula is the coldest place in the universe. I would say "in the _known_ universe"...
Absolute zero is when the movement of atoms stops, and for that to happen it'd have to have no external forces acting on it, which is quite impossible.
:)
I wouldn't be surprised if sometime in the very distant future absolute zero would be possible, but definitly not using any sort of current technology.
The fact is that heat is just the vibration of molecules which is another sort of movement (note that to cool something down you don't have to put something cool next to it - there are many other ways to cool something). To keep something totally still you'll need something to keep the thing still - how can you do that with an atom that measures nanometres wide?
The only way I could think of to do this would be to use strong electromagnetic force to keep the atom aligned or something, but then you're adding more energy to it!
One thing to think about: We can't have a static universe philisophically as without any movement then time would be irrelevant
It just seems likely to me that there's someplace out in the black which doesn't even have enough matter for heat to exist. That would be colder.
Call your local quantum mechanic. She'll tell you they don't cease to "vibrate": it's called zero point energy.
This nebula is weird because it's _colder_ than the ambient background temperature of the universe; some process must be going on to cool it, apparently the rapid expansion of the gas.
Ultimately, yes, the Universe seems doomed to cool down indefinitely. The Universe is expanding, and it seems that it isn't going to stop; the galaxies end up spread out much further, the background radiation redshifts further and further down into radio noise, the stars start dying off... The future is a cold, cold place. No energy is destroyed, it's just spread out thinner and thinner over time.
Real Daleks don't climb stairs - they level the building.
Ok, am giving up mod pts to post here, so here goes.
:-)
See, the point is that there is indeed a theory behind religion - it is the direct outcome of
socio-economic situations.
Religion is based on faith, that's what defines it.
Religion is based on a set of actions which are believed to constitute faith. That some people have faith is in itself besides the point.
Once you start having to 'justify' your beliefs, you have lost faith, and most religions (esp. Judeo-Christian ones) would not consider you a member based on your 'lack of faith'.
Agreed. But justification of a faith need not necessiate the lack of any.
No one gets into heaven (if your religion happens to have one) if they don't have complete faith.
Well no. A lot of Eastern Religions stress on your duty more than your faith. Sure, faith gets in too, but remember that your duty is the reason you're here.
I would not say that religion is a phenomenon that cannot be explained by theory, I would rather include it among the various socio-economic forces, and is perhaps an inevitable consequence. In fact, several behaviour and ritualistic factors of religion can be traced back to the state of the affairs when the religion flourished.
Anyways, my 0.02.
Some have been disussing a way to reach absolute zero. While I am not a physics major, I do love reading Hawking, Barbour, et. al. It's very mind expanding. I've ultimately decided you can not reach absolute zero wihtout cirumventing the laws of the universe and the means that we observe them... as we know it.
...
Okay, so I got thinking... if the space you're measuring was contained by a magnetic field and contained nothing, could it reach absolute zero? Theoretically I would think so. But there's 2 problems with this, right?
The first is simply the observation of "nothing." If I'm not mistaken, you can not measure or observe "nothing" because if it could be observed in any way, it would be "something". Even if you could somehow detect the abscense of "something" you'd be effecting "nothing" and making it into "something." Correct?
The second would be how do we define "nothing?" If I am to define it as something that does not contain matter in any form, then how do I contain it? Is it a matter of containment, or a matter of exclusion? If I am to exclude "something", philosphically this is far different from containing "nothing."
Anyway, I've got a headache now and it's 10 AM EST. Thank you slashdot for another wonderful morning
"Politicians find new names for institutions which under old names have become odious to the people."
"it is impossible to reach T=0 in a finite number of steps".
A bit out of my league, but isn't it also impossible to reach absolute zero because of the uncertainty principal? As I understand it, a molecule can "borrow" energy and exist in a given space for a bried period of time, including this "absolute zero" area.
As I understand it, the uncertainty principal is what determined that black holes "do have hair" (sorry Steven H.) and thus can dissipate, but at a rate that exceeds the entire history of the universe. In theory, this would prevent any given space from maintaining a mean temperature of exactly 0 for any given time, or more properly, it means that a given area with a temperature of 0 has a probability of not being 0.
Of course, I could be completely wrong....
Tequila: It's not just for breakfast anymore!
That theory was disproved long ago.
Anonymous Cowards suck.
this is not entirely true. at absolute zero atoms do in fact still vibrate. They must, or the uncertainty principle would be violated...
What absolute zero means is that each atom, or molecule, or whatever, is perfectly ordered (as far as quantum mecanics will allow) Each atom, ect. is in its lowest allowed quantum states. every one of them. Thus you know what state every atom is in at absolute zero.
Also, prolly the most practicle explination of why absolute zero cannot be reached is that as substances get colder and colder, it becomes harder and harder to cool them. Thus it takes more and more energy to cool a substance a unit of temperature. Also this quantity that tells us how well a substance exchanges heat energy with its suroundings (it is called specific heat) increases to infinity as you aproach absolute zero. Therefore, it would take an infinite amount of energy to bring a substance to absolute zero.
That, i think is the easiest explination of what we are talking about.
How many times are you going to repost the same link to the same flawed theory?
http://newton.umsl.edu/infophys/p1more.html: //fangio.magnet.fsu.edu/~vlad/pr100/100yrs/ht ml/chap/fs2_13054.htm (link to pdf on page)n egkelvi n/negkelvin.htmlr eates/1989/ramsey- autobio.html
Once. And please tell me how it is flawed. Negative absolute temperature was first rigorously described in 1956, and has been the subject of a lot of confirmed research since. The author of this first article was Norman Ramsey who later won a Nobel Prize for the invention of the MASER, the predecessor of the LASER. Som have called the MASER the modt important invention of the 20th Century. Ramsey is also famous for seminal work in NMR chemical shifts, etc.
Here are some DIFFERENT links on the same topic:
http://boojum.hut.fi/~pjh/nuclearmagnetism.htm
http
http://www.maxwellian.demon.co.uk/art/esa/
http://www.nobel.se/physics/lau
The coldest place in the universe is in 2001 Nobel Prize winner Carl Weinman's Lab in Boulder, Colorado. Temperatures as low as 3nK (3 billionths of a Kelvin) have been achieved.