# State of matter : absolute 0

by JPC
Tags: absolute, matter, state
 P: 230 just wondering how can matter be at a state for absolute 0 (0 kelvin), because it would mean that electrons arent moving , and that they've got no energy. Nothing moving doesnt seem very possible because theres the 4 fundamental forces ( example : how can the gravitational force of an object suddenly fade away) So is there a limit of extreme cold temperature for our maily atom-based environment ?
 Sci Advisor P: 5,772 Something at absolute 0 means it is in the lowest possible energy state, not that there is nothing moving.
 P: 230 oh ok but 0 kelvin means 0 energy right or is there still the minimum energy at 0 kelvin (the energy that we today cannot take away ; example : gravity)
P: 80

## State of matter : absolute 0

 Quote by JPC oh ok but 0 kelvin means 0 energy right or is there still the minimum energy at 0 kelvin (the energy that we today cannot take away ; example : gravity)
doesn't no energy mean no mass? no mass no gravity...
 P: 373 No. Zero kelvin means no thermal motion. It doesn't say anything else about other types of energy - that intrinsic to the matter in question. Taking the example of a bound electron, it *must* have a minimum kinetic energy for the bound state to exist. The electron will still occupy a non-zero kinetic energy state in its atom, it's just that the atom won't be moving.
 P: 158 absolute zero is more like an interesting limiting case then a physically realizable state. Any system will always have some thermal motion however small.
P: 1,136
 Quote by Allday absolute zero is more like an interesting limiting case then a physically realizable state. Any system will always have some thermal motion however small.
Doesn't stop people from stating what will happen at absolute zero despite their being no proof, and believing it to be true, as I've found many times, OK so a hypothesis sates that at absolute zero x will happen, now prove it?........ OK so it's just a hypothesis?

No that's what will happen according to QM?

So it's just a hypothesis?

No that's what will happen?

So what's your proof?

QM theory?

Oh my mistake in that case it must be true nm.
P: 80
 Quote by Sojourner01 Zero kelvin means no thermal motion. It doesn't say anything else about other types of energy
maybe gay-lussac isn't still valid, but when a gas reaches 0 kelvin (and it cant) then its volume should shrink to zero
P: 223
 Quote by Schrodinger's Dog Doesn't stop people from stating what will happen at absolute zero despite their being no proof, and believing it to be true, as I've found many times, OK so a hypothesis sates that at absolute zero x will happen, now prove it?........ OK so it's just a hypothesis? No that's what will happen according to QM? So it's just a hypothesis? No that's what will happen? So what's your proof? QM theory? Oh my mistake in that case it must be true nm.
I'm not sure what you're rambling about, but you can do a lot of solid physics at "zero" temperature and use it as the limiting case as your temperature becomes much smaller than the temperature scale you may be interested in.

For example, say I'm interested in the behavior of a superconductor much below its critical temperature. Wouldn't it be okay to try out the zero-temperature limit?
P: 1,136
 Quote by StatMechGuy I'm not sure what you're rambling about, but you can do a lot of solid physics at "zero" temperature and use it as the limiting case as your temperature becomes much smaller than the temperature scale you may be interested in. For example, say I'm interested in the behavior of a superconductor much below its critical temperature. Wouldn't it be okay to try out the zero-temperature limit?
I was referring to absolute zero actually, have you achieved it? If you have what happens when a material reaches absolute zero? If not can you tell me what may happen or what does happen?
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P: 5,057
 Quote by Schrodinger's Dog I was referring to absolute zero actually, have you achieved it?

This is not really relevant to the original poster's question. The velocity of a material is clearly NOT the thing that prevents a material from attaining absolute zero. Consider these two facts:

1. The earth is obviously moving through space at a considerable speed, although no one actually knows our true velocity.

2. Scientists have been able to achieve termperatures very very close to absolute zero. From Scientific American, Wolfgang Ketterle of the Massachusetts Institute of Technology, who won the Nobel Prize in Physics for his work with ultracold atoms, explains:

"In the 1980s and 1990s new methods for cooling atomic gases were developed: laser cooling and evaporative cooling. By combining these methods, temperatures below one nanokelvin (one billionth of a degree Kelvin) have been achieved. The lowest temperature recorded so far, described in a publication from our group in the September 12, 2003 issue of Science, is 450 picokelvins, which beat the previous record holder by a factor of six. Two recent Nobel prizes (in 1997 and 2001) were awarded for these developments."

Absolute zero represents the lowest possible energy state of matter. Achieving a trillionth of our everyday termperature clearly indicates that motion (through space) and gravity have nothing to do with achieving this feat.
P: 223
 Quote by Schrodinger's Dog I was referring to absolute zero actually, have you achieved it? If you have what happens when a material reaches absolute zero? If not can you tell me what may happen or what does happen?
Well, I've never sat on an inertial reference frame either. Have you? An exactly inertial reference frame? Why would we ever invent a concept if it only has good approximate value?
P: 4
 Quote by StatMechGuy Why would we ever invent a concept if it only has good approximate value?
All concepts have some amount of "approximate value". No concept has a higher degree than that, although some get extremely close.

The subject of this thread will get under some people's skin, because it's common for one thing or another, to be assumed to be greater than approximate and subsequently considered a "given".

The only given, is that all finite measurements are approximate and it can't be absolutely determined, how they arise from an infinite field.

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