Thermodynamics of the harmonic oscillator using coherent states

Abstract

The ongoing discussion whether thermodynamic properties can be extracted from a (possibly approximate) quantum mechanical time evolution using time averages is fed with an instructive example. It is shown for the harmonic oscillator how the Hilbert space or an appropriately defined phase space must be populated in terms of coherent states in order to obtain the quantum result respectively the classical one.

6 pages, 2 postscript figures, uses 'epsfig.sty'. Submitted to Europhysics Letters. Introduction changed and references added for the revised version. More information available at http://obelix.physik.uni-osnabrueck.de/~schnack/