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Semiclassical approximation to the partition function of a particle in D dimensions

C. A. A. de Carvalho·R. M. Cavalcanti·E. S. Fraga·S. E. Jorás
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Abstract

We use a path integral formalism to derive the semiclassical series for the partition function of a particle in D dimensions. We analyze in particular the case of attractive central potentials, obtaining explicit expressions for the fluctuation determinant and for the semiclassical two-point function in the special cases of the harmonic and single-well quartic anharmonic oscillators. The specific heat of the latter is compared to precise WKB estimates. We conclude by discussing the possible extension of our results to field theories.

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C. A. A. de Carvalho, R. M. Cavalcanti, E. S. Fraga, S. E. Jorás. 2000-03-15. Semiclassical approximation to the partition function of a particle in D dimensions. https://doi.org/10.1103/physreve.61.6392

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