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Author Topic: Has absolute zero ever been proved?  (Read 1765 times)

Offline bizerl

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Has absolute zero ever been proved?
« on: 16/07/2012 02:16:32 »
I'm wondering whether "absolute zero" is a calculated conclusion, or an observable phenomenon. If it is the latter, how is it observed?


 

Offline Bored chemist

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Re: Has absolute zero ever been proved?
« Reply #1 on: 16/07/2012 19:43:09 »
The calculations show that it's impossible to get there so it cannot be observed.
 

Offline bizerl

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Re: Has absolute zero ever been proved?
« Reply #2 on: 19/07/2012 04:25:11 »
So it's more like an asymptotal target? - We can get ever closer but never quite there?
 

Offline evan_au

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Re: Has absolute zero ever been proved?
« Reply #3 on: 21/07/2012 12:38:39 »
Yes - You can get closer and closer by expending more and more energy, but you can never quite get there.
For many years, scientists have observed some characteristics that appear close to absolute zero, including superconductivity and superfluidity.

The current record (in 2012) is less than a billionth of a degree above absolute zero.
This close to absolute zero, Bose-Einstein condensates have been created, where most of the atoms are at their lowest energy level, even though some of the atoms still have some higher energy. http://en.wikipedia.org/wiki/Absolute_zero#Relation_with_Bose.E2.80.93Einstein_condensates

According to Quantum Theory, you can never remove all of the energy from a system.
 

The Naked Scientists Forum

Re: Has absolute zero ever been proved?
« Reply #3 on: 21/07/2012 12:38:39 »

 

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