Jump to content

Talk:Quantum phase transition

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia
This is an old revision of this page, as edited by TimothyRias (talk | contribs) at 11:32, 10 December 2008. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
WikiProject iconPhysics Stub‑class Low‑importance
WikiProject iconThis article is within the scope of WikiProject Physics, a collaborative effort to improve the coverage of Physics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
StubThis article has been rated as Stub-class on Wikipedia's content assessment scale.
LowThis article has been rated as Low-importance on the project's importance scale.

What does "Such quantum phase transitions can be phase transition or continuous" mean? I guess it is a typo. What should it say?

what is so "quantum" about a QPT?

I fail to see in what sense quantum effects are relevant for a QPT. Take a classical antiferromagnetic spin lattice, for example: why shouldn't there be a zero temperature phase transition when the external magnetic field is varied? There is a well-defined (possibly degenerate) classical ground state, and its energy might change in a non-analytic way under variation of the magnetic field.

Also, the statement "A classical system does not have entropy at zero temperature" also applies in the quantum case since a pure state has vanishing entropy. - Saibod 11:05, 31 August 2007 (UTC)[reply]