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Alternative Derivation of the Hu-Paz-Zhang Master Equation for Quantum Brownian Motion

J. J. Halliwell·T. Yu
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Abstract

Hu, Paz and Zhang [ B.L. Hu, J.P. Paz and Y. Zhang, Phys. Rev. D {\bf 45} (1992) 2843] have derived an exact master equation for quantum Brownian motion in a general environment via path integral techniques. Their master equation provides a very useful tool to study the decoherence of a quantum system due to the interaction with its environment. In this paper, we give an alternative and elementary derivation of the Hu-Paz-Zhang master equation, which involves tracing the evolution equation for the Wigner function. We also discuss the master equation in some special cases.

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J. J. Halliwell, T. Yu. 1995-08-04. Alternative Derivation of the Hu-Paz-Zhang Master Equation for Quantum Brownian Motion. https://doi.org/10.1103/physrevd.53.2012

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