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Calculation of the microcanonical temperature for the classical Bose field

Matthew J. Davis·P. Blair Blakie
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Abstract

The ergodic hypothesis asserts that a classical mechanical system will in time visit every available configuration in phase space. Thus, for an ergodic system, an ensemble average of a thermodynamic quantity can equally well be calculated by a time average over a sufficiently long period of dynamical evolution. In this paper we describe in detail how to calculate the temperature and chemical potential from the dynamics of a microcanonical classical field, using the particular example of the classical modes of a Bose-condensed gas. The accurate determination of these thermodynamics quantities is essential in measuring the shift of the critical temperature of a Bose gas due to non-perturbative many-body effects.

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Matthew J. Davis, P. Blair Blakie. 2007-06-20. Calculation of the microcanonical temperature for the classical Bose field. https://doi.org/10.1088/0305-4470%2F38%2F48%2F001

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