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Exact derivation of the Langevin and master equations for harmonic quantum Brownian motion

Edgardo T. Garcia Alvarez·Fabian H. Gaioli
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Abstract

A many particle Hamiltonian, where the interaction term conserves the number of particles, is considered. A master equation for the populations of the different levels is derived in an exact way. It results in a local equation with time-dependent coefficients, which can be identified with the transition probabilities in the golden rule approximation. A reinterpretation of the model as a set of coupled harmonic oscillators enables one to obtain for one of them an exact local Langevin equation, with time-dependent coefficients.

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Edgardo T. Garcia Alvarez, Fabian H. Gaioli. 1998-07-17. Exact derivation of the Langevin and master equations for harmonic quantum Brownian motion. https://doi.org/10.1016/s0378-4371(98)00148-4

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