Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: bizerl on 16/07/2012 02:16:32

Title: Has absolute zero ever been proved?
Post by: bizerl 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?

Title: Re: Has absolute zero ever been proved?
Post by: Bored chemist on 16/07/2012 19:43:09

The calculations show that it's impossible to get there so it cannot be observed.

Title: Re: Has absolute zero ever been proved?
Post by: bizerl on 19/07/2012 04:25:11

So it's more like an asymptotal target? - We can get ever closer but never quite there?

Title: Re: Has absolute zero ever been proved?
Post by: evan_au 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.