Talk:Entropy (statistical thermodynamics)
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Discrete quantum states?
This article states: "Usually, the quantum states are discrete...." Is this true? If so, what is the explanation? (How is position discrete?) I would be interested to see some references. (I could not find the word "discrete" in the article on "quantum states"). 188.8.131.52 (talk) 05:47, 20 April 2008 (UTC)
Might want to discuss difference between Gibbs and Boltzmann for negative absolute temperature
As in, Gibbs works, Boltzmann doesn't work: http://web.mit.edu/newsoffice/2013/its-a-negative-on-negative-absolute-temperatures-1220.html?goback=%2Egde_36972_member_5822015646686277636#%21 — Preceding unsigned comment added by 184.108.40.206 (talk) 23:17, 28 December 2013 (UTC)
- The odd thing about that article is they focus only on results applying to the the microcanonical ensemble, and though they say they read Gibbs it seems they didn't notice his warnings against both the "Boltzmann entropy" and "Gibbs entropy" (as they are called in the article). Both have problems, though the Boltzmann entropy certainly has more problems. Besides these, Gibbs also discussed a third definition of entropy in the context of the canonical ensemble, and in that case the negative absolute temperatures are again permitted, for some special kinds of systems (the system's density of states must vanish sufficiently quickly at high energies). The correspondence of this third entropy to the thermodynamic entropy is very appealing, even outside the thermodynamic limit. You can find Gibbs' thoughts in Elementary Principles in Statistical Mechanics, especially in chapter XIV. I recently added text to the microcanonical ensemble article on just this topic, so have a read. --Nanite (talk) 21:10, 2 January 2014 (UTC)
I've added a template at top of article suggesting moving into Entropy, just as Entropy (classical thermodynamics) has a similar proposal to merge into Entropy. It isn't a different "entropy" that's the subject of this article; just a different theory or model or set of methods for analyzing/understanding/explaining entropy or making predictions about phenomena. DavRosen (talk) 16:10, 22 July 2013 (UTC)