Dec
6
Has anyone ever reached 0 degrees Kelvin?
Filed Under Physics
? TOKIO HOTEL ? asked:
I think the closest anyone has ever gotten is around 0.01pK. But i’m not exaclty too sure about the difference in the units K and pK.
I think the closest anyone has ever gotten is around 0.01pK. But i’m not exaclty too sure about the difference in the units K and pK.
I’ve looked up a few things already and i got a few names of Scientists and research groups that have attempted 0K what are a few that you know of?
and lastly where does cryogenics stand in all of this?
Elmo Live
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6 Responses to “Has anyone ever reached 0 degrees Kelvin?”
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No, and it’s thermodynamically impossible
From what I understand, it is impossible to reach absolute zero.
Your Right …. they reached a very close degree to 0K but nobody ever reached 0.00000000000 K
some of those are the Helsinki University of Technology, which has reported reaching temperatures of 100 pK, and, MIT researchers which reported achieved 500 pK, cryogenics is about things at really low temperature, they observe matter at really low temperature, you know, how they react and stuff, so, of course it stands in all of this, it’s the name of field that we’re talking about,
No, it’s absoloutely impossible to reach 0 degrees Kelvin, although scientists have been able to come quite close to it. Theoretically (and it could be argued) time stops when the temperature reaches 0 degrees Kelvin due to electrons not moving around the nucleus of atoms anymore. I don’t know everything about it, but I believe that’s the basic idea. Please correct me if I’m wrong
You couldn’t get to 0K for thermodynamic reasons. But many people have gotten very close.
To answer some of your specific question, 1 pK is equal to 1×10^-12 K, or 1 millionth of 1 millionth of a degree K.
The people who get really close to zero K are the BEC groups (Bose-Einstein Condensates). The first two groups to do this (the ones that won the Nobel prize) are Wolfgang Ketterle at MIT and Carl Wieman and Eric Cornell at the University of Colorado - Boulder. Since they accomplished this, there have been many groups that started up BEC experiments and get very cold. But these experiments are more interested in how very cold thing act than making cold things just for the sake of making cold things. So the difference between 100pK and 500pK is not a concern for them.
There are similar types of experiments trying to make cold Fermi gases that get to similar temperatures. Laser cooling, followed by evaporative cooling is used to get these very low temperatures. Laser cooling is a very common technique in a lost of atomic physics these days, so quite a few groups can cool down to very low temperatures. There are experiments to try to cool macroscopic objects like mirrors and cantilevers to very low temperatures using lasers and similar techniques. These can get down to the mK range (1/1000 K) but nowhere near the BEC range. Cryogens usually implies liquid nitrogen or liquid helium which are at 77K and 4K respectively. There are als0 certain types of refrigerators like dilution refrigerators that can cool down into the few mK range.