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Non-Abelian linear Boltzmann equation and quantum correction to Kramers and Smoluchowski equation

Bassano Vacchini
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Abstract

A quantum linear Boltzmann equation is proposed, constructed in terms of the operator-valued dynamic structure factor of the macroscopic system the test particle is interacting with. Due to this operator structure it is a non-Abelian linear Boltzmann equation and when expressed through the Wigner function it allows for a direct comparison with the classical one. Considering a Brownian particle the corresponding Fokker-Planck equation is obtained in a most direct way taking the limit of small energy and momentum transfer. A typically quantum correction to the Kramers equation thus appears, describing diffusion in position and further implying a correction to Einstein's diffusion coefficient in the high temperature and friction limit in which Smoluchowski equation emerges.

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Bassano Vacchini. 2002-04-19. Non-Abelian linear Boltzmann equation and quantum correction to Kramers and Smoluchowski equation. https://doi.org/10.1103/physreve.66.027107

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