On the Harmonic Oscillator Regularization of Partition Functions

Kåre Olaussen

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On the Harmonic Oscillator Regularization of Partition Functions

Kåre Olaussen

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Abstract

A convenient way to calculate $N$-particle quantum partition functions is by confining the particles in a weak harmonic potential instead of using a finite box or periodic boundary conditions. There is, however, a slightly different connection between partition functions and thermodynamic quantities with such volume regularization. This is made explicit, and its origin explained to be due to the system having a space-varying density in an external potential. Beyond perturbation theory there is a potential pitfall with the method, which is pointed out.

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Kåre Olaussen. 1992-07-04. On the Harmonic Oscillator Regularization of Partition Functions. https://arxiv.org/abs/cond-mat/9207005

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