Effective classical partition functions

1986/12/01 by Richard P. Feynman, H. Kleinert · 21 citations
Physics and Astronomy · #Quantum, superfluid, helium dynamics #Spectroscopy and Quantum Chemical Studies #Cold Atom Physics and Bose-Einstein Condensates

paper · doi:10.1103/physreva.34.5080

openalex publication_date 1986/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We present a method by which a quantum-mechanical partition function can be approximated from below by an effective classical partition function. The associated potential is obtained by a simple smearing procedure. For a strongly anharmonic oscillator and a double-well potential, the lowest approximation gives a free energy which is accurate to a few percent, even at zero temperature.

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