Journal of Physics Conference Series

Path integral of charged particle in black cavity

Hagen M. Kleinert

Published Apr 1, 2006• 1 citation

Abstract

We solve the forward-backward path integral for a point particle in a bath of photons and derive from it a master equation for the density matrix with electromagnetic dissipation, as well as the associated Langevin equation. The path integral approach yields an alternative access to the Wigner-Weisskopf formula for the natural line width of an atomic state at zero temperature and, in addition, the temperature broadening caused by decoherence.

DOI: 10.1088/1742-6596/35/1/003

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